A pole layer incorporates: a first portion having an end face located in a medium facing surface; and a second portion having a thickness greater than that of the first portion. A surface of the first portion closer to a substrate is located farther from the substrate than a surface of the second portion closer to the substrate. A surface of the first portion farther from the substrate is located closer to the substrate than a surface of the second portion farther from the substrate. At least a portion of the pole layer is placed in an encasing groove formed in a region extending from a first encasing layer through a second encasing layer to a nonmagnetic metal layer.

1. Field of the Invention
The present invention relates to a magnetic head for perpendicular magnetic recording that is used for writing data on a recording medium by using a perpendicular magnetic recording system and to a method of manufacturing such a magnetic head.
2. Description of the Related Art
The recording systems of magnetic read/write devices include a longitudinal magnetic recording system wherein signals are magnetized in the direction along the surface of the recording medium (the longitudinal direction) and a perpendicular magnetic recording system wherein signals are magnetized in the direction orthogonal to the surface of the recording medium. It is known that the perpendicular magnetic recording system is harder to be affected by thermal fluctuation of the recording medium and capable of implementing higher linear recording density, compared with the longitudinal magnetic recording system.
Like magnetic heads for longitudinal magnetic recording, magnetic heads for perpendicular magnetic recording typically used have a structure in which a reproducing (read) head having a magnetoresistive element (that may be hereinafter called an MR element) for reading and a recording (write) head having an induction-type electromagnetic transducer for writing are stacked on a substrate. The write head comprises a magnetic pole layer that produces a magnetic field in the direction orthogonal to the surface of the recording medium. The pole layer incorporates a track width defining portion and a wide portion, for example. The track width defining portion has an end located in a medium facing surface that faces toward the recording medium. The wide portion is coupled to the other end of the track width defining portion and has a width greater than the width of the track width defining portion. The track width defining portion has a nearly uniform width.
For the perpendicular magnetic recording system, it is an improvement in recording medium and an improvement in write head that mainly contributes to an improvement in recording density. It is a reduction in track width and an improvement in writing characteristics that is particularly required for the write head to achieve higher recording density. On the other hand, if the track width is reduced, the writing characteristics, such as an overwrite property that is a parameter indicating an overwriting capability, are reduced. It is therefore required to achieve better writing characteristics as the track width is reduced. Here, the length of the track width defining portion orthogonal to the medium facing surface is called a neck height. The smaller the neck height, the better is the overwrite property.
A magnetic head used for a magnetic disk drive such as a hard disk drive is typically provided in a slider. The slider has the above-mentioned medium facing surface. The medium facing surface has an air-inflow-side end and an air-outflow-side end. The slider slightly flies over the surface of the recording medium by means of the airflow that comes from the air-inflow-side end into the space between the medium facing surface and the recording medium. The magnetic head is typically disposed near the air-outflow-side end of the medium facing surface of the slider. In a magnetic disk drive the magnetic head is aligned through the use of a rotary actuator, for example. In this case, the magnetic head moves over the recording medium along a circular orbit centered on the center of rotation of the rotary actuator. In such a magnetic disk drive, a tilt called a skew of the magnetic head is created with respect to the tangent of the circular track, in accordance with the position of the magnetic head across the tracks.
In a magnetic disk drive of the perpendicular magnetic recording system that exhibits a better capability of writing on a recording medium than the longitudinal magnetic recording system, in particular, if the above-mentioned skew is created, problems arise, such as a phenomenon in which data stored on an adjacent track is erased when data is written on a specific track (that is hereinafter called adjacent track erasing) or unwanted writing is performed between adjacent two tracks. To achieve higher recording density, it is required to suppress adjacent track erasing. Unwanted writing between adjacent two tracks affects detection of servo signals for alignment of the magnetic head and the signal-to-noise ratio of a read signal.
A technique is known for preventing the problems resulting from the skew as described above, as disclosed in the U.S. Patent Application Publication No. US2003/0151850 A1 and the U.S. Pat. No. 6,504,675B1, for example. According to this technique, the end face of the track width defining portion located in the medium facing surface is made to have a shape in which the side located backward in the direction of travel of the recording medium (that is, the side located on the air-inflow-end side of the slider) is shorter than the opposite side. Typically, in the medium facing surface of a magnetic head, the end farther from the substrate is located forward in the direction of travel of the recording medium (that is, on the air-outflow-end side of the slider). Therefore, the above-mentioned shape of the end face of the track width defining portion located in the medium facing surface is such a shape that the side closer to the substrate is shorter than the side farther from the substrate.
As a magnetic head for perpendicular magnetic recording, a magnetic head comprising a pole layer and a shield is known, as disclosed in the U.S. Pat. No. 4,656,546, for example. In the medium facing surface of this magnetic head, an end face of the shield is located forward of an end face of the pole layer along the direction of travel of the recording medium with a specific small space therebetween. Such a magnetic head will be hereinafter called a shield-type head. In the shield-type head, the shield prevents a magnetic flux from reaching the recording medium, the flux being generated from the end face of the pole layer and extending in directions except the direction orthogonal to the surface of the recording medium. The shield-type head achieves a further improvement in linear recording density.
The U.S. Pat. No. 5,726,839 discloses a technique for reducing the thickness of a portion of the pole layer (the main pole) near the medium facing surface such that this portion is thinner than the other portion of the pole layer.
The U.S. Patent Application Publication No. US2002/0034043 A1 discloses a technique in which a portion of the pole layer (the main pole) near the medium facing surface is made to have a thickness that decreases as the distance from the medium facing surface decreases.
The U.S. Patent Application Publication No. US2002/0080524 A1 and the U.S. Patent Application Publication No. US2003/0193744 A1 disclose a technique in which a yoke layer thicker than a main pole layer is magnetically coupled to the main pole layer. An end face of the yoke layer closer to the medium facing surface is located at a distance from the medium facing surface. To form the main pole layer and the yoke layer, these layers are individually patterned, according to the U.S. Patent Application Publication No. US2002/0080524 A1 and the U.S. Patent Application Publication No. US2003/0193744 A1.
The Published Unexamined Japanese Patent Application 2003-6811 discloses a technique in which a portion of a pole layer (a second magnetic layer) near the medium facing surface is made to have a thickness smaller than that of the other portion of the pole layer. In this publication, one of surfaces of the portion of the pole layer near the medium facing surface closer to the substrate is located farther form the substrate than one of surfaces of the other portion of the pole layer closer to the substrate. In addition, this publication discloses a method of forming the pole layer in the following manner. In this method, first, a base of the pole layer is etched to define the shape of the base. Next, the pole layer is formed on the base by frame plating. A protection layer is then formed to cover the pole layer. Next, the top surfaces of the protection layer and the pole layer are polished to flatten these top surfaces. Through this polishing, the thickness of the pole layer taken in the medium facing surface is determined.
The U.S. Patent Application Publication No. US2004/0228033 A1 discloses a technique for reducing the thickness of a portion of a pole layer (main pole layer) near the medium facing surface so that this thickness is made smaller than that of the other portion of the pole layer. In this publication, one of surfaces of the portion of the pole layer near the medium facing surface closer to the substrate is located farther form the substrate than one of surfaces of the other portion of the pole layer closer to the substrate. In this publication, the pole layer incorporates a first layer and a second layer stacked on the first layer. This publication discloses a method of forming the pole layer in the following manner. In this method, first, a base of the pole layer is etched to form a concave portion in which the first layer is to be formed in a top surface of the base. Next, the first layer is formed in the concave portion by sputtering. Next, a magnetic layer to be the second layer is formed on the first layer by sputtering. The magnetic layer and the first layer are then selectively etched. The magnetic layer is formed into the second layer through this etching. Next, an insulating layer is formed to cover the second layer. Next, the insulating layer and the second layer are polished until the second layer is exposed, and the top surfaces of the insulating layer and the second layer are thereby flattened. Through this polishing, the thickness of the pole layer taken in the medium facing surface is defined.
Here, a combination of the main pole layer and the yoke layer that are disclosed in the U.S. Patent Application Publication No. US2002/0080524 A1 and the U.S. Patent Application Publication No. US2003/0193744A1 is called a pole layer for convenience. It is a technique for making a portion of the pole layer near the medium facing surface have a thickness smaller than that of the other portion of the pole layer that is disclosed in each of the U.S. Pat. No. 5,726,839, the U.S. Patent Application Publication No. US2002/0034043 A1, the U.S. Patent Application Publication No. US2002/0080524 A1, the U.S. Patent Application Publication No. US2003/0193744 A1, the Published Unexamined Japanese Patent Application 2003-6811, and the U.S. Patent Application Publication No. US2004/0228033 A1.
Consideration will now be given to a method of forming a pole layer having a track width defining portion with an end face that is located in the medium facing surface and that has a shape in which the side closer to the substrate is shorter than the side farther from the substrate as described above. It is frame plating that has been often used in prior art for forming such a pole layer. In a method of forming the pole layer by frame plating, an electrode film is first formed on a base of the pole layer. Next, a photoresist layer is formed on the electrode film. The photoresist layer is then patterned to form a frame having a groove whose shape corresponds to the pole layer. Next, plating is performed by feeding a current to the electrode film to form the pole layer in the groove. The frame is then removed. Next, the electrode film except a portion located below the pole layer is removed. Next, an insulating layer made of alumina, for example, is formed to cover the pole layer. Next, the insulating layer and the pole layer are polished by chemical mechanical polishing (hereinafter referred to as CMP), for example. Through the polishing, the top surface of the pole layer is flattened, and the thickness of the pole layer is controlled to be of a desired value.
It is difficult through the foregoing method of forming the pole layer to control the level at which polishing is stopped with precision. If the polishing is stopped at a level other than a desired level, the thickness of the pole layer is made other than a desired thickness, and the track width defined by the length of the above-mentioned side farther from the substrate is thereby made other than a desired value. Therefore, the foregoing method of forming the pole layer has a problem that it is difficult to control the track width with precision.
The U.S. Patent Application Publication No. US2003/0151850 A1 discloses a technique in which a groove having a shape corresponding to a pole layer is formed in an inorganic insulating film, and the pole layer is formed in the groove by plating or sputtering. In this method, the width of the pole layer, that is, the track width, is determined by the width of the groove formed in the inorganic insulating film. In addition, this publication discloses a technique in which the end face of the track width defining portion located in the medium facing surface is made to have a shape having a first portion and a second portion. The first portion has a width that continuously increases from an end on the air-inflow-end side to an end on the air-outflow-end side. The second portion is located on the air-outflow-end side of the first portion and has a uniform width that is equal to the width of the end of the first portion on the air-outflow-end side. Accorsing to this technique, it is possible to reduce variations in track width.
To solve the problems resulting from the skew, it is also effective to reduce the thickness of the track width defining portion taken in the medium facing surface. However, if the thickness of the entire pole layer is reduced, the cross-sectional area of the pole layer orthogonal to the direction in which the magnetic flux flows is reduced. As a result, it is impossible that the pole layer introduces a magnetic flux of great magnitude to the medium facing surface, and the overwrite property is thereby reduced.
As disclosed in the U.S. Pat. No. 5,726,839, the U.S. Patent Application Publication No. US2002/0034043 A1, the U.S. Patent Application Publication No. US2002/0080524 A1, the U.S. Patent Application Publication No. US2003/0193744 A1, the Published Unexamined Japanese Patent Application 2003-6811, and the U.S. Patent Application Publication No. US2004/0228033 A1, a portion of the pole layer near the medium facing surface is made to have a thickness smaller than that of the other portion of the pole layer. This results in a reduction in thickness of the track width defining portion taken in the medium facing surface, and it is thereby possible that the pole layer introduces a magnetic flux of great magnitude to the medium facing surface. However, it is difficult to precisely form the pole layer having such a shape that the portion near the medium facing surface has a thickness smaller than that of the other portion.
According to the technique disclosed in each of the U.S. Patent Application Publication No. US2002/0080524 A1 and the U.S. Patent Application Publication No. US2003/0193744 A1, the pole layer is made up of the two layers including the main pole layer and the yoke layer. The main pole layer and the yoke layer are formed by patterning individually. In this case, however, there arises a problem that it is difficult to align the main pole layer and the yoke layer with accuracy and the writing characteristic varies if the main pole layer and the yoke layer are misaligned.
According to the technique disclosed in each of the U.S. Patent Application Publication No. US2002/0080524 A1 and the U.S. Patent Application Publication No. US2003/0193744 A1, the yoke layer is thicker than the main pole layer. As a result, there is a great variation in thickness of a portion of the pole layer in the location of the end face of the yoke layer closer to the medium facing surface. In this portion in which the thickness varies, it is likely that flux leakage from the pole layer occurs. Consequently, if the portion is close to the medium facing surface, the leakage flux from the portion reaches the medium facing surface and further leaks to the outside from the medium facing surface. As a result, the effective track width is increased and/or the above-mentioned problems resulting from the skew occur.
Here, a case is considered in which the end face of the yoke layer closer to the medium facing surface is divided into two portions that are disposed on both sides of a surface that passes through the middle of the end face of the main pole layer in the medium facing surface and that is orthogonal to the medium facing surface and the substrate surface, the middle of the end face being taken along the direction of track width. In the technique disclosed in each of the U.S. Patent Application Publication No. US2002/0080524 A1 and the U.S. Patent Application Publication No. US2003/0193744 A1, if the locations of the main pole layer and the yoke layer are greatly shifted in the direction of track width, it is likely that flux leakage occurs from one of the above-mentioned two portions that has a greater area. As a result, the effective track width increases and/or the above-mentioned problems resulting from the skew occur.
In the method of forming the pole layer disclosed in the Japanese Published Unexamined Patent Application 2003-6811, the thickness of the pole layer taken in the medium facing surface is determined by polishing and flattening the top surface of the pole layer formed by frame plating. However, it is difficult to control the level at which the polishing is stopped with precision in this method as described above, and it is therefore difficult to control the track width with precision.
In the method of forming the pole layer disclosed in the U.S. Patent Application Publication No. US2004/0228033 A1, the thickness of the pole layer taken in the medium facing surface is determined by polishing and flattening the top surface of the second layer. However, it is difficult to control the level at which the polishing is stopped with precision in this method as described above, and it is therefore difficult to control the track width with precision.

Magnetic head for perpendicular magnetic recording and method of manufacturing same


The present invention relates to a high-resolution magnetic resonance imaging (MRI) image generating method using a new MRI image method called a generalized series parallel imaging technique, and a recording medium thereof. In the high-resolution MRI image generating method using the generalized series parallel imaging technique according to the present invention, selecting only a predetermined low frequency band of all frequency bands, and sampling the predetermined low frequency band of all frequency bands at a lower rate than a Nyquist rate to acquire magnetic resonance data.

1. Field of the Invention
The present invention relates to a method for generating high resolution Magnetic Resonance Imaging (hereinafter, referred to as "MRI") image.
2. Description of the Background Art
MRI is used for measuring magnetic properties of material and producing the image thereof and there have been many studies in this field. One of conventional MRI techniques can monitor physiological information of human body tissues and magnetic resonance properties of water molecules according to the types of diseases. In line with this trend, the system performance of a MRI apparatus has gradually been improved.
Functional MRI (hereinafter, referred to as "fMRI") is an imaging method for determining which part of the brain is activated according to time when the brain is under the stimulus of the sense of sight, auditory sense, movement or the like. The fMRI requires high temporal resolutions.
As a conventional method for obtaining this fMRI, an Echo Planar Imaging (hereinafter, referred to as "EPI") technique with high temporal resolution has been used a lot.
The EPI technique can be used suitably when the size of an fMRI image is 64×64, but is difficult to use when the size of an fMRI image is over 64×64 due to a low signal to noise ratio (SNR). Further, the EPI technique is advantageous in that it can obtain an image quickly unlike other conventional MRI methods, such as a gradient-echo imaging and a spin-echo imaging, but is disadvantageous in that ghost artifact or geometric distortion is generated.
Further, a MRI apparatus with an intensity of 1.5 T (Teals) or 3.0 T (Tesla) has generally been used in some hospitals or research institutes and an fMRI with this degree of a magnetic field strength is also used. However, in recent years, as an MRI apparatus with a higher magnetic field is advanced, an ultra-high field system of 7.0 T (Tesla) has begun to be used. However, it is expected that fMRI photographing using the EPI technique in this ultra-high field system is impossible because the above-described problems stands out more than the low Tesla system. Accordingly, there is a need for a method of photographing a general MRI image more quickly without EPI technique.
The Generalized Series (hereinafter, referred to as "GS") imaging technique and the parallel imaging technique, are described below with reference to the accompanying drawings.
FIG. 1 is a view illustrating a sampling method of the GS imaging technique.
The sampling method of the GS imaging technique is generally used to acquire an MRI with high temporal resolution and is a method of shortening an image acquisition time based on the fact that images in neighboring time-frames are similar to each other (refer to a reference document: Z-F. Liang and P. C. Lauterbur. An Efficient Method for Dynamic Magnetic Resonance Imaging. IEEE Transactions on Medical Imaging 1994; 13:677-686).
Referring to FIG. 1, the left-side drawing of FIG. 1 illustrates a case where magnetic resonance data is acquired by sampling it at the Nyquist rate over the whole k-space region. This method corresponds to a sampling method of a conventional imaging technique. The right-side drawing of FIG. 1 illustrates a case where magnetic resonance data is acquired by sampling it at the Nyquist rate with respect to only the low frequency region of a central portion of the whole region of the k-space. This method corresponds to a sampling method of the GS imaging technique. The term "Nyquist rate" refers to that an original signal can be recovered only when the signal is sampled at a sampling frequency twice an original signal frequency bandwidth. This minimum sampling frequency is called the Nyquist rate.
The right-side drawing of FIG. 1 shows a case where the data acquisition time is twice faster than that of the left-side drawing of FIG. 1. However, the data acquisition time can be further shortened depending on how many sampling number is set by a user.
In the sampling method of the GS imaging technique, it can be said that the high frequency component of an image is lost because only the low frequency component is sampled, but the high frequency component can be compensated for by a reference image to be obtained once for the first time by the sampling method of the conventional imaging technique. The sampling method of the GS imaging technique can shorten the image acquisition time by using the fact that images in neighboring time-frames are similar when acquiring a dynamic MRI (hereinafter, referred to as "dMRI").
In the sampling method of the GS imaging technique, an image IGS is represented into a linear combination, assuming that the image IGS is a function as in the following equation 1. An image that is finally reconstructed becomes IGS.
                                          I            GS                                          (            x            )                          =                              ∑            n                                                        c              n                                                                  ϕ                n                                                          (                x                )                                                                        [                  Equation                                                              1                ]
where φn(x) is a basis function.
Equation 1 can be represented by a complex number sine series as in the following equation 2.
                                                        ϕ              n                                                  (              x              )                                =                                                    I                r                                                          (                x                )                                                                ⅇ                              ⅈ2π                                                                                k                  n                                                x                                                    ,                                                                              I              GS                                                  (              x              )                                =                                                    I                r                                                          (                x                )                                                                                ∑                n                                                                            c                  n                                                                  ⅇ                                      ⅈ2π                                                                                k                      n                                                            x                                                                                [                  Equation                                                              2                ]
where Il(x) is a reference image obtained by a general imaging method. Thus, if only cn is found, a desired image can be obtained. This can be decided by a condition that fulfills in a Fourier transform relationship such as the following equation 3.
                              Constaint                                :                                                                                d              q                                                  (              m              )                                =                                    ∑              x                                                                                I                  GS                                                                  (                  x                  )                                                                          ⅇ                                                      -                    ⅈ2π                                                                                k                    m                                                      x                                                                                d                        q                                                                                (                        m                        )                                                              =                                                                  ∑                        x                                                                                I                            r                                                                                (                            x                            )                                                                                ∑                            n                                                                                c                              n                                                                                ⅇ                                                              ⅈ2π                                                                                k                                  n                                                                                x                                                                                ⅇ                                                                                -                                  ⅈ                                                                                2                                                                π                                                                                k                                  m                                                                                x                                                                                =                                                                  ∑                        n                                                                                ∑                          x                                                                                c                            n                                                                                I                            r                                                                                ⅇ                                                                                -                                ⅈ                                                                                2                                                                                π                                                                                (                                                                                k                                      m                                                                        -                                                                          k                                      n                                                                                )                                                                                x                                                                                =                                                                  ∑                        n                                                                                c                          n                                                                                d                                                      c                                                                                (                                                                                k                                  m                                                                -                                                                  k                                  n                                                                                )                                                                                ∴                                          d                q                                                          (                m                )                                              =                                    ∑                              n                =                1                            M                                                                  c                n                                                                            d                  c                                                                  (                                                            k                      m                                        -                                          k                      n                                                        )                                                                                [                  Equation                                                              3                ]
where dc(m) are the Fourier transformation results of Ic(x) and dq(m) is the Fourier transformation results of an image obtained by the sampling method of the GS imaging technique.
As described above, the sampling method of the GS imaging technique is a method of shortening an image acquisition time by sampling only M lines in a low frequency region of the whole k-space region. The sampling method of the GS imaging technique with respect to a one-dimensional signal has been described so far. It is, however, to be noted that this method can be applied to two-dimensional signals.
FIG. 2 is a view illustrating a sampling method of the parallel imaging technique.
FIG. 2(a) is a view illustrating a sensitivity encoding (SENSE) sampling method, which is one of parallel imaging techniques. For reference, SENSE is described in detail in a reference document (Pruessmann K P, Weiger M, Scheidegger M B, Boesiger P. Sense: sensitivity encoding for fast MRI. Magn Reson Med 1999; 42:952-962).
FIG. 2(b) shows a final MRI reconstructed by performing the Fourier transformation on magnetic resonance data obtained by the SENSE sampling method of FIG. 2(a).
In FIG. 2(a), the left-side drawing of FIG. 2(a) illustrates a case where magnetic resonance data is acquired at the Nyquist sampling distance with respect to the whole k-space region, which corresponds to the sampling method of the conventional imaging technique. The right-side drawing of FIG. 2(a) illustrates a case where magnetic resonance data is acquired at a distance twice the Nyquist sampling distance with respect to the whole k-space region, which corresponds to the sampling method of the parallel imaging technique. A data acquisition time of these methods would be twice faster than that of the conventional imaging technique. It is called reduction factor (R)=2. If the Fourier transformation is applied to the data obtained as described above, an image of a shape in which a reconstructed final MRI is folded once (2-fold) is obtained as shown in FIG. 2(b). The right-side drawing of FIG. 2(a) illustrates a case where the data acquisition time is twice fast compared with the left-side drawing of FIG. 2(a). However, the data acquisition time can be further reduced by a user depending on an image whose distance is how much greater than the Nyquist sampling distance.
In the parallel imaging technique, data is received by using a multi-channel coil such as a phased-array coil. In this case, aliasing images as many as the channel number can be obtained. Each channel has its unique property. This property decides whether the intensity of a specific portion in an image is displayed greater than the remaining portions. For example, when the number of channels is 4, top, bottom, left, and right portions of each channel have the intensity greater than that of the remaining portions. It is used as additional information for eliminating an aliasing phenomenon.
FIG. 2(b) illustrates the final MRI in which the brain of a human being is obtained as twice (R=2) the Nyquist distance by using a 4-channel coil. From FIG. 2(b), it can be seen that the images are the same, but are different in intensity distributions on a channel basis.
Images with different intensity distributions on a channel basis as described above can be modeled on the assumption that an image with uniform intensity distributions is multiplied by a component to represent the intensity. To indicate how the intensity is strong on a position basis, as described above, is called a sensitivity map. In order words, the degree of aliasing every image of each channel is dependent on the sensitivity. In this case, a case R=2 can be expressed in the following equation 4.
                                          [                                                                                S                    11                                                                                S                    12                                                                                S                    21                                                                                S                    22                                                                                ⋮                                                  ⋮                                                                                S                    41                                                                                S                    42                                                                        ]                                          [                                                                                U                    1                                                                                U                    2                                                                        ]                          =                  [                                                                      v                  1                                                                                v                  2                                                                                ⋮                                                                                v                  4                                                              ]                                    [                  Equation                                                              4                ]
Where Sij is the sensitivity of an image that enters a jth aliasing term of an ith channel. In FIG. 2, j can comprise only 1 or 2 because of R=2. That is, a case where j is 1 corresponds to an original signal and a case where j is 2 corresponds to a signal serving as the aliasing term. In a similar way, Ui is a signal value of an image that enters a jth aliasing term and Vi is a value of an aliasing signal of an ith channel. This can be expressed in a simplified form as in the following equation 5.SU=V  [Equation 5]
where data obtained through an experiment is V. Thus, if only S can be calculated through an algorithm, U can be known from a matrix equation such as the following equation 6.SU=V,STSU=STV,∴U=(STS)−1STV  [Equation 6]
where S is the above-mentioned sensitivity map. It can be found by applying an appropriate polynomial fitting process to the reference image obtained by the conventional imaging technique.
The GS imaging technique and the parallel imaging technique can be applied to an ultra-high field system without ghost artifact or geometric distortion, but is disadvantageous in that a speed in which a final MRI is obtained is slow compared with the EPI technique.
FIG. 3 is a view illustrating a previous method to improve image quality using GS and parallel imaging techniques. The technique of FIG. 3 corresponds to the method proposed by Xu (refer to a reference document: Xu D, Ying L, and Liang Z P. Parallel Generalized Series MRI: Algorithm and Application to Cancer Imaging. In: Proceedings of the 26th Annual International Conference of the IEEE EMBS, San Francisco, 2004).
The k-space sampling method proposed by Xu is a method of sampling M lines at the Nyquist rate in the central portion of the k-space and loosely sampling them at a rate lower than the Nyquist rate in the external portions of the k-space other than the central portion. Thus, the fact that only the central portion is to be sampled at the Nyquist rate leads to the characteristic of the GS imaging technique, and the fact that only the external portions are to be sampled loosely leads to the characteristic of the parallel imaging technique.
As shown in FIG. 3, the outermost left-side drawing of FIG. 3 is a k-space sampling diagram used to obtain a reference image and also used to acquire a conventional imaging, and the right-side drawing of FIG. 3 corresponds to the sampling method proposed by Xu.
The method proposed by Xu is focused on improving the quality of an image that is further reconstructed by combining the GS imaging technique and the parallel imaging technique. This method is basically not a method of further increasing temporal resolutions. Accordingly, in this method, the quality of a reconstructed image is better compared with when using each imaging technique (the GS imaging technique or the parallel imaging technique), but is problematic in that temporal resolutions are lowered.

Method for generating high resolution MRI image and recording medium thereof

Korea Advanced Institute of Science & Technology


In a freezer-equipped refrigerator, a refrigerating chamber or freezing chamber is divided into a plurality of sections having substantially same temperature zone. A temperature element is provided in each section, and an open/close damper and a duct for supplying cool wind for each section are also provided. In such a structure, control is made on whether or not cool wind should be supplied or not in accordance with a detected temperature.

1. Field of the Invention
The present invention relates to a cool air supply in a freezer-equipped refrigerator.
2. Description of the Related Art
FIGS. 13 to 16 show conventional cool air wind passage structures. FIG. 13 is an appearance view of a conventional freezer-equipped refrigerator. FIG. 14 is a transparent perspective view showing a cool air wind structure of the conventional freezer-equipped refrigerator. As seen from FIG. 13, a freezer-equipped refrigerator 1 includes a refrigerating chamber 2 and freezing chambers 3 located below the refrigerating chamber 2. As shown in FIG. 14, the freezing chamber 3 incorporates a heat exchanger 4 and a fan 5 for circulating cool air located above the fan 5. The cool wind blown off from the fan 5 is branched into several areas. It blows off into the refrigerating chamber 2 as follows. It is taken in from an inlet 6, passes a duct 8 via an opening/closing damper 7 and blows off toward respective shelves from cool air blow-off openings 9. The blown off cool wind cools food or others in the refrigerating chamber 2 and drawn into an inhalation inlet 10. The cool wind further passes a return wind passage 11 to return to the lower part of the heat exchanger 4. Then, the cool wind is cooled again by the heat exchanger 4 and sent to the refrigerating chamber 2 and the like, and such circulation is repeated. Reference numeral 12 represents an element for detecting the temperature within the refrigerating chamber. FIG. 15 shows a control substrate 80 for controlling whether or not the circulation of cool wind should be carried out. FIG. 16 is a flowchart of a control of the circulation of cool wind. When the element 12 detects that the temperature of the refrigerating chamber 2 is higher than a setting value, the fan 5 rotates and the damper 7 opens so that cool wind is supplied to the respective shelves of the refrigerating chamber 2. Incidentally, in this case, it is assumed that a compressor for supplying refrigerant to the heat exchanger is rotating. When the temperature of the refrigerating chamber 2 detected by the element 12 is lower than the setting value, the damper 7 is closed. The fan 5, in accordance with the temperature of other chambers, continues to rotate or stops. By the repetition of such an operation, the temperature of the refrigerating chamber 2 is controlled so as to be constant.
One example of the conventional technique is disclosed in Japanese Patent Examined Application Hei. 7-11379.
Owing to the structure and control described above, the conventional freezer-equipped refrigerator has the following problems. If the chamber in a uniform temperature zone are sectioned by plural shelves or boxes, the temperature difference between the temperature of the element 12 and the sectioned places is increased. Accordingly, it is difficult to maintain the temperature of the refrigerating chamber at a predetermined temperature. Additionally, when the door of the refrigerating chamber 2 is opened, the temperature of the refrigerating chamber 2 increases. However, the temperature does not increase uniformly, and the temperature of an upper zone is increased. If the setting value is lowered in order to suppress such a phenomenon, inversely the temperature of the lowest section becomes lower than the setting value.


A new and distinct Coleus plant cultivar is disclosed, characterized by deeply lobed, undulating leaves, neon green and magenta foliage, a compact growth habit and short internodes.

The new cultivar 'MD CURLL06' was discovered as a naturally occurring whole plant mutation of the parent Coleus plant variety 'Bienvenue' (not patented). The new cultivar was discovered in May 1998 as a single plant in a cultivated area of Glienicke, Germany.
Asexual reproduction of the new cultivar 'MD CURLL06' by terminal cuttings was first performed in 1998 in Oxnard, Calif. and has shown that the unique features of this new cultivar are stable and reproduced true to type on successive generations.


A system is disclosed for controlling the roll of a motor vehicle. The system comprises a selective lock connected between an unsprung portion of the vehicle and a sprung portion of the vehicle.

This invention relates in general to motor vehicle roll control systems and in particular to a self-centering actuator for a roll control system, and a roll control system including a self-centering actuator.
Suspension systems for a motor vehicle are known which isolate the vehicle load from irregularities in the terrain over which the vehicle travels. A semi-active suspension system, for example, normally includes a spring and a damper connected between the sprung and unsprung portions of the vehicle. Semi-active suspension systems are generally self-contained, and only react to the loads applied to them. In active suspension systems, by contrast, the reactions to the applied loads are positively supplied, typically by electronically controlled hydraulic or pneumatic actuators.
In addition to isolating the sprung portion of the vehicle from the road, it is desirable to stabilize the vehicle and resist the tendency of the sprung portion of the vehicle to tilt or roll relative to its unsprung portion when accelerating, decelerating or cornering at relatively high rates. Therefore, suspension systems have been proposed to maintain the vehicle in an essentially level position, regardless of the source of the force seeking to upset that position. For example, U.S. Pat. No. 5,630,623 to Ganzel, the disclosures of which are incorporated herein by reference, discloses a semi-active system for controlling the roll of a motor vehicle including an actuator connected between an unsprung portion of the vehicle and a sprung portion of the vehicle. The known roll control system of U.S. Pat. No. 5,630,623 not only locks and unlocks the anti-roll bars of the vehicle, but also accommodates the upward or downward deflections of any of the four wheels of the vehicle, regardless of whether the affected wheel is on the inside or outside of the turn, as will be described in more detail below.
Referring now to the drawings, FIGS. 1 and 2 show the prior art semi-active, pumpless system 10 for controlling the roll of a motor vehicle according to U.S. Pat. No. 5,630,623. The system 10 comprises a front hydraulic circuit 11a and a rear hydraulic circuit 11b. The front hydraulic circuit 11a includes a front actuator 12, first and second pressure control or pressure relief valves 14 and 16, and first and second check valves 18 and 20. The rear hydraulic circuit 11b includes a second rear actuator 21 and other components similar to those of the front hydraulic circuit 11a which will be discussed below.
Each of the wheels 22, 24, 26 and 28 of the vehicle is rotationally mounted about a substantially horizontal axis to a member such as suspension arms 30, 32, 34 and 36, respectively, which form part of an unsprung portion of the vehicle. The unsprung portion of the vehicle is in turn connected to a sprung portion of the vehicle through the actuators 12 and 21 and anti-roll or anti-sway bars 38 and 40.
Each of the actuators 12 and 21 includes a cylinder 42 and a piston 44 reciprocably disposed in the respective cylinder 42. One of the cylinder 42 or the piston 44 of each actuator 12, 21 is drivingly connected to an associated one of the anti-roll bar 38, 40 or the suspension arm 30, 32, 43, 36 while the other component of each cylinder/piston pair is drivingly connected to the associated other of the anti-roll bar 38, 40 or the suspension arm 30, 32, 43, 36. As shown in FIGS. 1 and 2, for example, the cylinder 42 of the front actuator 12 is connected to one free end of the front anti-roll bar 38, while the portion of the piston rod extending generally downwardly from the cylinder is connected to the front right suspension arm 30. Similarly, the rear anti-roll bar 40 is coupled to the cylinder 42 of the right rear actuator 21 while the piston 44 of the actuator 21 is connected to the suspension arm 32.
The actuators 12 and 21 each have a pair of ports, respectively 46, 48 and 50, 52, through which a working medium such as hydraulic fluid may be alternately provided to or evacuated from the ends of the cylinders 42 disposed on either side of the pistons 44 situated therein. As described more fully below, each of the actuators 12 and 21 serves to maintain the sprung height from the road surface of the portion of the vehicle body above its associated wheel.
The first pressure control valve 14 is a proportional relief valve, and is in communication with the first port 46 of the actuator 12 through a hydraulic line 54. The valve 14 is operated by a proportional solenoid, and has an open position and a closed position. In response to actual or anticipated loading of the actuator 12, the solenoid energizes the valve 14 toward the closed position with a force proportional to an electric signal applied thereto, which prevents flow away from the first port 46 until a predetermined pressure develops in the upper chamber of the cylinder 42 to overcome the solenoid force, as described more fully below. The first check valve 18 is situated in the hydraulic circuit in parallel with the first pressure control valve 14, and permits flow therethrough only in a direction toward the first port 46 of the actuator 12.
The second pressure control valve 16 is also a proportional relief valve, and is in communication with the second port 48 of the actuator 12 through a hydraulic line 56. The valve 16 is also controlled by a proportional solenoid, and can be moved between open and closed positions by the solenoid to prevent flow away from the second port 48 until a predetermined pressure develops in the lower chamber of the cylinder 42. The second check valve 20 is situated in the hydraulic circuit in parallel with the second pressure control valve 16 and permits flow therethrough only toward the second port 48 of the actuator 12.
The rear hydraulic circuit 11b for the rear actuator 21 is substantially identical to the hydraulic circuit 1a for the front actuator 12. Thus, a proportional pressure control valve 58 and a parallel check valve 60 are provided in communication with the first port 50 of the rear actuator 21, and another proportional pressure control valve 62 and a parallel check valve 64 are provided in communication with the second port 52 of the rear actuator 21.
In operation, an electronic control unit (ECU) 70, processes inputs from one or more wheel speed sensors 72, a lateral accelerometer 74, and a steering angle sensor 76. Given these inputs, the ECU 70 predicts the severity of an upcoming roll, and issues control commands to the solenoids of the appropriate valves 14 and 58 or 16 and 62. For example, the motor vehicle may begin a relatively high speed left hand turn. Such a turn, in absence of compensation by the system 10, would cause the unsprung portion of the vehicle to tend to roll generally clockwise about it longitudinal axis.
At the beginning of such a maneuver, sensors 72, 74 and 76 signal the instantaneous conditions to the ECU 70. The ECU 70 in turn calculates or obtains from a look up table the net pressure P that needs to be developed in the upper chambers of the cylinders 42 of one or both of the actuators 12 and 21 to counteract the vehicle roll, and energizes the solenoids of the pressure control valves 14 and 58 an amount sufficient to resist flow through those valves up to the pressure P.
To counteract anticipated vehicle roll in the opposite direction, for example as might be experienced during a right hand turn, the ECU 70 repeats this procedure and energizes the solenoids of the valves 16 and 62 to allow build up of the pressure in the lower chambers of both actuator 12 and 21. In either case, as the sensors 72, 74 and 76 indicate an instantaneous or anticipated reduction or increase in the need for counteracting vehicle roll, the ECU 70 signals the appropriate pressure control valves to correspondingly reduce or increase their pressure cut out limit.
If an unexpected load is imposed on one of the actuators, such as might occur when one wheel rolls over a bump in the road, an increased pressure is developed in one chamber of the affected actuator. For example, if the right front wheel 22 encounters a bump and deflects upwardly during a left hand turn, the piston 44 is displaced upwardly in the cylinder 42 and the pressure in the upper chamber of the actuator 12 increases. Even if the valve 14 is energized closed at this time (to resist the anticipated roll), the increased pressure overcomes the solenoid force, allowing the suspension to compress and maintain ride quality. After the wheel 22 then passes over the top of the bump and begins to move downward and the valve 14 closes again, the check valve 18 allows the piston 44 and the suspension arm 30 to fall back down without any resistance from the roll control system. This process takes a finite amount of time, during which the vehicle body will likely roll to the right to some extent, due to the left hand turn. Since fluid was displaced out of the upper chamber of the actuator 12, the piston 44 and the suspension arm 30 are unlikely to return entirely to their original positions by the time pressure in the upper chamber of the actuator 12 returns to it's pre-upset level, and the actuator 12 will remain in a slightly more compressed state than prior to the wheel hitting the bump, allowing more than desired roll to the right during the left hand turn.
Again, considering a left-hand turn, in the event that the left front wheel 28 suddenly rises while the valve 14 is energized closed, the suspension arm 36 moves upwardly and the anti-roll bar 38 above the actuator 12 moves to a new upwardly elevated position relative to the control arm 30, acting to extend in the cylinder 42, and reducing the pressure in the upper chamber of the actuator 12. If the pressure in the upper chamber drops below the pressure in pre-charged accumulator 78, the check valve 18 allows flow into the upper chamber of the actuator 12 so that there is essentially no resistance from the actuator 12 to the extension of the actuator 12. The new extended position may be near the original position or may be beyond, i.e., in a more extended position than the original position, depending on the amount of flow allowed into the upper chamber of the actuator 12.
Again, considering a left-hand turn if the anti-roll bar 38 were originally in a center or neutral position and, for example, the valve 14 is energized with the anti-roll bar 38 out of the original position, when the anti-roll bar 38 is extended into a new position, that new position may be near the original position or past, i.e., past the central or neutral position to a more compressed position than the original position. Thus, it can be said that the actuator 12 can go beyond neutral in both directions, i.e., the actuator 12 can end up in position in which the actuator 12 is either extended more or compressed more than the condition of the actuator 12 at the neutral position.
The accumulator 78 is situated in each of the front and rear hydraulic circuits in communication with the pressure control valves 14, 16 and 58, 62. By maintaining the fluid in the hydraulic circuits under a certain pressure, the accumulator 78 functions to prevent cavitation in the system 10 when the wheels of the vehicle deflect, and also acts as a reservoir to replenish any fluid lost by the system to leakage past dynamic seals. All of the valves and the accumulator for each of the front and rear hydraulic circuits 11a and 11b are packaged in units 80 and 82 mounted near the anti-roll bars 38 and 40. The front and rear hydraulic circuits 11a and 11b are kept separate so that the valves of each circuit can ride with their respective anti-roll bar, which eliminates the need for running expensive flexible hydraulic hoses from the body of the vehicle to the front rear anti-roll bar.

Vehicle roll control system with self-centering actuator


A system and method for automatically configuring routing for international telephone calls in a hierarchy of switches. The present invention provides a set of routing rules to route international telephone calls through a hierarchy of switches. The rules act upon data stored in a computer. The data is stored in a configuration table. The configuration table contains information describing network topology. Using the network topology data, the rules generate routing tables. The routing tables provide routing for international telephone calls through a switch hierarchy.

1. Field of the Invention
The present invention relates generally to switch routing in a telecommunications network. More particularly, the present invention relates to generating international switch routing according to a set of rules describing desired routing behavior using a description of a switch hierarchy.
2. Related Art
Long distance telephone service is provided via a hierarchical network of switches. Each switch within the hierarchy is responsible for providing a connection from each input to the switch to each output of the switch. The switches connect sources of telephone calls to their destination. A familiar example is where a caller in a first city, the source, desires to call a recipient in a second city, the destination. The switches in the hierarchy route the call from the caller to the intended recipient. The hierarchical organization of the network evolved in response to an increased number of subscribers, and demand for longer distance communications. The hierarchical system of switches provides a large amount of flexibility for routing calls between switches. Routing for domestic calls (within United States) has been automated to take advantage of the flexibility. In domestic routing, a computer automatically configures the routing of a network according to a specific set of routing rules.
Unfortunately, the situation is not so refined for the case of international call routing. This is due to an additional complexity in the switch hierarchy. The additional complexity results from gateway switches that are used to route international calls to an appropriate country. Every international call must be routed through a gateway switch if it cannot be directly routed to the country. Instances of direct routing are rare. Moreover, international calls provide multiple services, whereas conventional domestic calling only provides one service, voice. Different routing schemes are often required for the different services available with international calls.
Conventionally, configuring the switches to route international calls through a domestic network has been a manual process. The process entails reconfiguring domestic switches to identify and route international calls to a gateway switch. Because of the extensive amount of human intervention required to reconfigure the switches, the process is not only time consuming, but the potential for error is significant. As more countries are added to an international network, the manual process become even more cumbersome and consequently, the potential for error increases. Thus, what is required is an automatic routing system to automatically configure a network's routing to route international telephone calls through a domestic network to a gateway switch.

System and method for automatically generating a routing plan for international telephony


Disclosed is an air conditioner (AC) indoor unit including a housing installed on the ceiling and having an inlet and an outlet provided around the inlet and having a pair of straight sections facing each other and a pair of curved sections facing each other; a heat exchanger provided inside the housing and arranged in a main flow path between the inlet and the outlet; a blower fan configured to suck in air through the inlet, allow the air to exchange heat with the heat exchanger, and discharge the air through the outlet; and an auxiliary flow path guiding an auxiliary air current to change a direction of an air current discharged from the outlet. The direction of the discharged air current may be controlled by sucking in air around the outlet or blowing air to the periphery of the outlet through the auxiliary flow path without a blade.

An air conditioner (AC) is equipped with a compressor, a condenser, an expansion valve, an evaporator, a blower fan, and the like, for controlling indoor temperature, humidity, air currents, etc., using refrigeration cycles. The ACs may be classified into split air conditioners having two separate parts: the indoor unit to be installed indoors and the outdoor unit to be installed outdoors, and packaged ACs having the indoor unit and the outdoor unit located in a single housing.
The AC indoor unit includes a heat exchanger for exchanging heat between a refrigerant and air, a blower fan for circulating air, and a motor for driving the blower fan, to cool or heat the indoor space.
The AC indoor unit may also have a means for controlling a discharged air current, to discharge the air cooled or heated by the heat exchanger in various directions. The means for controlling a discharged air current may commonly include a vertical or horizontal blade equipped in an outlet, and a driving system for driving the blade to turn. The AC indoor unit controls the direction of an air current by controlling the turning angle of the blade.
With the structure to control a discharged air current using the blade, the amount of discharged air may be reduced because the blade interferes with the air flow, and circulating noise may increase due to the turbulence produced around the blade. Furthermore, since a pivot axis of the blade is formed to be straight, the shape of the outlet is restricted to the straight shape.


A method and apparatus for digital down conversion and demodulation of a radio frequency (RF) signal are disclosed. A sampling frequency for sampling the RF signal is chosen, based on a bandwidth and a safety margin, so that a bandwidth of the sampled signal falls substantially within a predetermined frequency zone. The sampled signal may be digitally demodulated at a demodulation frequency selected to be substantially equal to a baseband alias of a carrier frequency of the signal.

In wireless receivers, the RF signal that is captured by an antenna of the receiver must be converted to baseband before the information in the signal can be extracted and used by applications. Many wireless communication standards use quadrature modulation to impress information onto an RF carrier. To demodulate such signals, receivers typically use one of a variety of analog processing methods implemented in one of a variety of receiver types, including: heterodyne receivers, super-heterodyne receivers, homodyne receivers, single conversion low intermediate frequency (IF) receivers, and double conversion wideband IF receivers.
Analog receiver designs are typically difficult to modify and tune and must be customized for a particular frequency band of operation. Newer wireless standards, such as the long term evolution (LTE) standard specify many different bands of operation. One drawback of using analog designs for operation over different frequency bands is the non-recurring engineering cost associated with a re-design of a receiver for each and every frequency band.
Further, designs that rely on analog processing suffer from performance degradation caused by electronic noise, temperature variations, voltage variations, manufacturing defects and component aging. Therefore, receiver designs that minimize reliance on analog processing are desired.

Digital down conversion and demodulation


A data storage device includes a write protection data structure that includes a first set of entries corresponding to a first set of ranges of memory addresses. A first indication stored in an entry, in the first set of entries, corresponds to an absence of write-protected data between a lowest address of the range of addresses corresponding to the entry and a highest address of a memory. A second indication stored in the entry corresponds to write-protected data within the range of addresses. The data storage device also includes a write protection map that includes a second set of entries corresponding to a second set of ranges of the memory addresses. The device is configured to locate, in the write protection data structure, an entry corresponding to a range of memory addresses.

Non-volatile data storage devices, such as universal serial bus (USB) flash memory devices or removable storage cards, have allowed for increased portability of data and software applications. Such devices may enable data to be stored by a host device and later retrieved from a memory in the data storage device. For example, a host device may send a write command to a data storage device and specify a memory address. The data storage device may store data to a memory location indicated by the memory address.
When a write command is received from a host device, the data storage device may be responsible for ensuring that write-protected data stored in the memory is not overwritten by the host device. The data storage device may maintain a write protection map that identifies whether write protection is enabled for each memory address that maps to a location in the memory. For example, a write protection map may have a write protection indicator for each group of memory addresses, such as sector-sized groups (e.g., 512 bytes), page-sized groups (e.g., 2 kilobytes), or other-sized groups of memory addresses. Starting at the address provided by the host device, the data storage device may "walk" through the write protection map, in response to receiving a write command, to identify a total amount of sequentially addressed space that is not write-protected to determine a largest amount of data that may be stored in response to the write command.
However, because memory capacity increases with advances in storage technologies, a size of the write protection map may also increase. An amount of time expended walking through the write protection map creates write latency experienced by the host device. For example, when a first address following the write address is write protected, the write protection map search may be completed in a few microseconds. However, when the write address is near a beginning of an address space and a first address of write protected data is near an end of the address space, the write protection map search may take tens of microseconds to complete.

Method and non-volatile memory device for improving latency together with write protection


A weapon orientation measuring device in accordance with the disclosure includes a processor configured to receive first location information indicative of locations of a first point and a second point on a weapon, the first and second points being a known distance apart in a direction parallel to a pointing axis of the weapon, and to receive second location information indicative of the locations of the first and second points on the weapon. The processor is further configured to receive information indicative of a first earth orientation, and determine a second earth orientation corresponding to the weapon based on the first and second location information and the information indicative of the first earth orientation. The first location information represents location relative to a first sensor at a first location and the second location information represents location relative to a second sensor at a second location, and the first and second sensors are separated by a given distance.

The Multiple Integrated Laser Engagement System (MILES) is a modern, realistic force-on-force training system. An exemplary MILES system is the MILES 2000® system produced by Cubic Defense Systems, Inc. As a standard for direct-fire tactical engagement simulation, MILES 2000 is used by the United States Army, Marine Corps, and Air Force. MILES 2000 has also been adopted by international forces such as NATO, the United Kingdom Ministry of Defense, the Royal Netherlands Marine Corps, and the Kuwait Land Forces.
MILES 2000 includes wearable systems for individual soldiers and marines as well as devices for use with combat vehicles (including pyrotechnic devices), personnel carriers, antitank weapons, and pop-up and stand-alone targets. The MILES 2000 laser-based system allows troops to fire infrared "bullets" from the same weapons and vehicles that they would use in actual combat. These simulated combat events produce realistic audio/visual effects and casualties, identified as a "hit," "miss," or "kill." The events may be recorded, replayed and analyzed in detail during After Action Reviews which give commanders and participants an opportunity to review their performance during the training exercise. Unique player ID codes and Global Positioning System (GPS) technology ensure accurate data collection, including casualty assessments and participant positioning.
MILES systems may some day be phased out. One possible system that may replace MILES is the One Tactical Engagement Simulation System (OneTESS) currently being studied by the U.S. Army. Every aspect of the OneTESS design focuses on being engagement-centric, meaning that target-shooter pairings (often referred to as geometric pairings) need to be determined. In other words, the OneTESS system will need to predict, after a player fires a weapon, what the target is and whether or not a hit or miss results when a player activates (e.g. shoots) a weapon. In order to establish target-shooter pairings, the OneTESS system needs to determine what the intended target was and whether or not a hit or miss occurred, both of which depend on the orientation of the weapon, and other factors (e.g., weapon type, type of ammunition, etc.). Accurate determinations of the target-shooter pairings and accurate determinations of hit or miss decisions depend on the accuracy in which the orientation of the weapon at the time of firing can be determined.

Method and apparatus for measuring weapon pointing angles


The present invention provides an image pickup device in which a column noise component is detected in a short time without being influenced under variant random noise even if the VOPB area B includes a small number of lines, and pixel signals from the effective pixel area A are corrected, based on the detected column noise component. The image pickup device includes a solid-state image pickup element having a pixel part including an effective pixel area to be irradiated with light, and a light-shielded pixel area where irradiation of light is shielded, a vertical scanning circuit, a horizontal scanning circuit, and an output circuit, a controller that controls the solid-state image pickup element such that the pixel signals outputted from the pixels arranged in the light-shielded pixel area or the pixel signals outputted from the pixels arranged in the effective pixel area are outputted from the output circuit, a control signal generator that generates a predetermined control signal, a noise component detector that detects noise, and a noise corrector that corrects noise contained in the pixel signals from the effective pixel area based on a noise component detected by the noise component detector, wherein the control signal generator generates different control signals at predetermined timing.

1. Field of the Invention
The present invention relates to an image pickup device which picks up an image of an object by use of an XY address type solid-state image pickup element, and a signal processing method for the image pickup device.
2. Description of the Related Art
In a solid-state image pickup element 1 of an XY address type represented by a CMOS (complementary metal oxide semiconductor) sensor, a large number of pixels are arrayed in a matrix of lines and columns, as shown in FIG. 1. The element 1 has a vertical scanning circuit 54 to sequentially select lines of a pixel part 52, a horizontal scanning circuit 60 to sequentially select columns of the pixel part 52, and an output circuit 61 to output signals.
The vertical scanning circuit 54 and the horizontal scanning circuit 60 are constituted by, for example, shift-registers, and generate one vertical scanning pulse and one horizontal scanning pulse for every line and column, respectively.
When reading image signals charged in respective pixels, a pulse signal is added to one vertical selection line 53 by the vertical scanning circuit 54, to electrically conduct all pixel transistors 51 in one line. Image signals are read from respective photosensitive parts 50 onto vertical signal lines 55. The image signals read onto the vertical signal lines 55 are fed to circuits such as a correlative double sampling circuit (CDS) 56 and the like to remove an offset signal for every pixel.
The horizontal scanning circuit 60 adds a pulse signal to transistors 57 connected to the respective vertical signal lines 55 through horizontal selection lines 59, to electrically conduct the transistors 57. Pixel signals from a column from which offset signals have been removed by the CDS 56 are read onto a horizontal signal line 58. The signals are converted into voltage signals by an output circuit 61, and are outputted to the outside.
In an XY address type solid-state image pickup element of this kind, the columns respectively have different (or their own) vertical signal lines 55. Hence, pixel signals fed from the output circuit 61 are offset differently between individual columns if the CDSs 56 and the transistors 57 have characteristic variants. Various offsets which are respectively specific to the columns appear, as stripe-like fixed-pattern noise (hereinafter called column noise) on a display screen, and cause deterioration in image quality.
There has been a method for preventing this deterioration. In the method, only the column noise component is extracted from the solid-state image pickup element, and is maintained as a reference signal for correction. During a normal image pickup operation, the reference signal is subtracted from a signal output from the solid-state image pickup element, to correct column noise.
However, when the pixel part 52 is irradiated with light, a signal component based on the incident light is added to the column noise component. Therefore, this output signal cannot be used as a reference signal for correction. Hence, according to Japanese Patent Application Laid-Open Publication No. 10-126697, the pixel part 52 is constituted by an effective pixel area A, a vertical optical black (hereinafter abbreviated as VOPB) area B, and a horizontal optical black (HOPB) area C, as shown in FIG. 2. The effective pixel area A is irradiated with light. In the vertical optical black area B and the horizontal optical black area C, irradiation of light is shielded over several lines to several ten lines by a light-shield plate such as an aluminum thin film, conducting detection and correction of column noise.
Meanwhile, the offset of each column which causes column noise appears in outputs not only from pixels positioned in the effective pixel area A but also from pixels positioned in the VOPB area B as a shielded black level reference. Therefore, correction can be achieved in a manner that column noise components are detected by use of signals from the pixels in the VOPB area B and are subtracted from signals from the pixels from the effective pixel area A.

This patent is subject to a terminal disclaimer.

Image pickup device and signal processing method


Machining of aluminum workpieces with diamond or diamond-like carbon-surface coated tools may be conducted in an atmosphere containing hydrogen gas at a partial pressure effective for hydrogen to react with carbon atoms at the surface to form C—H bonds that resist adherence of aluminum to the tool surface. Suitably, hydrogen or a hydrogen-containing gas mixture is confined at the interface of tool and workpieces at the machining site. Hydrogen partial pressure may be determined for a tool-workpiece-machining temperature combination by calculation or experiment.

Aluminum alloy workpieces, especially castings, are used in making many articles of manufacture. In the automobile industry, for example, many engine and transmission parts, chassis parts, body parts, and interior parts are made of silicon-containing aluminum alloy castings. Many of these parts such as engine blocks, cylinder heads, crank cases, transmission cases, and the like are initially formed as castings using sand molding, permanent mold, high pressure die casting, and lost foam processes. Following these casting process, many surfaces of the parts still have to be machined to specified dimensions within very close tolerances.
Aluminum alloy 319 ("AA319") is an example of an aluminum alloy that is used to form cast shapes of many of the above parts. A representative nominal composition, by weight, of AA319 is 5.5 to 6.5% silicon, up to about 1% iron, 3 to 4% copper, about 0.5% manganese, about 0.1% magnesium, about 0.35% nickel, 1-3% zinc, about 0.25% titanium, and the balance substantially aluminum. The silicon content contributes fluidity to the molten alloy for the pouring of intricate cast shapes. But the silicon, and sometimes other alloying elements, form secondary phases in the predominately aluminum matrix that tend to abrade machining tools.
Engine and transmission castings, for example, may require precision machining processes such as milling, drilling, honing, and reaming. In these machining processes the casting is carefully positioned in a fixture and a cutting tool, carried and powered by an operator or computer controlled machine tool, cuts a cast surface to remove chips of workpiece metal to bring the surface to a specified finish quality and dimension. The tools for metal removal may be made of a hard material, especially the surface of the tool that engages the workpiece. For example, tools may be made of a tool steel composition or of a sintered composition comprising tungsten carbide, or the like. Sometimes the cutting surface of the tool may be coated with a hard carbon material such as polycrystalline diamond or diamond-like carbon.
The tendency of Al and its alloys to adhere to tool surfaces may create enormous difficulties in metal forming operations such as rolling, forging, casting, extrusion, and machining. Aluminum has a 3 to 6 nm thick natural oxide layer, which is locally destroyed during the forming process, exposing nascent Al metal that is highly chemically reactive. Once the oxide layer is destroyed, the onset of gross adhesive transfer to the tool surface is likely: this introduces process instability and threatens the success of the deformation process.
In conventional metal removal operations, the machined surface may be flooded with a machining liquid (water based or oil based) for the purposes of cooling and lubricating the region impacted by the cutting tool. The lubrication promotes cutting by minimizing adherence between the tool and the machined surface. Ultimately, the machining liquid must be drained from the machining area for recovery processing and re-use, or for disposal.
Wear resistance of a tool for cutting or otherwise machining a workpiece may be improved by coating a contact area of the tool with a hard material layer. Suitable hard coating materials for these tools often include carbon, common examples of which are diamond, hard carbon, and various forms of mixtures of sp2 and sp3 hybridized amorphous carbon.
Wet or dry machining processes may be used to machine a workpiece using the hard coated tools. Drawbacks with using wet machining processes, for example, include relatively high costs of performing the wet machining process and, in some cases, environmental concerns potentially linked to use of coolants or other machining fluids. Dry machining processes, especially for machining soft metals such as aluminum alloys, for example, may lead to adhesion of the aluminum alloy workpiece to the tool surface, thereby diminishing the operative life of the tool.
It is an object of this invention to provide a method for machining aluminum alloy workpieces (e.g., castings) without the use of such a machining liquid. In accordance with this invention such a practice is termed "dry machining."


This invention is a process for the production of a continuous running length of a thermosetting polymer by a continuously extruding a continuous running length of a sheath of a film forming fiber from a die to form a hollow object; b) continuously injecting the monomer of the thermosetting polymer into the hollow of the sheath at or immediately below the plane of the die opening; c) stretching the sheath containing the monomer; and d) polymerizing the monomer to make the continuous running length of fiber of thermosetting polymer.

Such a method is known from EP-A-254,915, in which, in order to produce a light-transmitting, optical fiber, a hollow tube of thermoplastic material is filled with the monomer of the thermosetting polymer, which is then polymerized by subjecting the filled tube to a temperature treatment.
A drawback of this known process is the limited length in which the object can be obtained, while fibers, including optical fibers, are normally used in very great lengths. In addition, from lines 12-16 on page 4 and Example 1, lines 4-7 of page 19 of the aforementioned patent application it is apparent that the production rate is limited to between a few decimeters and a few meters per hour, which makes this process hardly applicable in economic terms.
Melt processing of thermosetting polymers, once they have cured is not possible. Therefore, manufacture of objects of thermosetting materials as a rule takes place by introducing the corresponding monomer into a mold of the desired shape and then polymerizing it, the resulting object having the shape of the mold. At low temperatures, for instance room temperature, most monomers of thermosetting polymers are liquids, which cannot be shaped to self supporting objects, so that spinning or extruding of the monomer does not yield continuous objects or running lengths which can be handled in further treatments. That is why for the continuous manufacture of continuous objects or running lengths of thermosetting polymers, in marked contrast to the situation for thermoplastic polymers, no economically applicable techniques are known. Patent publication JP-A-61/262707 does describe a controlled manner of gradual polymerization of a polymerizable monomer, yielding a prepolymer with a viscosity that makes it suitable for spinning, followed by spinning of the prepolymer--already possessing some internal cohesion due to the partial polymerization--and subsequent further polymerization. But this process requires very precise control and consequently has low flow through rates and it is economically unattractive because of the resulting low production speed.

Process for the production of a continuous object of a theromosetting polymer


A ball extracting device (1, 14) for removing a golf ball (8) from holes and other locations which is integrally attachable to a golf club shaft (3) on the grip (13) of a golf club. The device is a cylindrically-shaped module having side walls (18), a bottom (19) and an open top (7) for extracting and retaining a golf ball (8) when downward pressure is applied to the device (1, 14) against the ball (8). The walls (18) contain holes (5) therethrough so that a golfer's fingers can be inserted to facilitate easy removal of the ball from the device. The extracting device (1, 14) can be incorporated either with a replacement grip (2) that fits over the shaft of a golf club, a grip that covers a preexisting grip, or a cap-like module (14) that fits over the end of a golf club grip. All versions of the device work in the same manner and do not require modification to the existing golf club. This device eliminates the need for stressful bending when extracting golf balls from holes or other places, particularly for handicapped golfers, golfers with back problems, elderly golfers, or those with medical conditions such as arthritis.

This invention relates generally to golfing, and more particularly to golf ball retrieving and extracting devices that fit or attach to golf clubs.
Normally, at the completion of each hole golfers must bend over to remove a golf ball from the cup. Also, oftentimes during play golfers may have to bend over numerous times to remove golf balls from hazards, such as grass or water. Although bending over is usually not a problem for the young golfer, it can be a strenuous and virtually impossible task for the elderly, anyone with back problems, arthritis, or a handicapped golfer. Thus, there is a need for a device that will extract golf balls from such locations without requiring the golfer to bend over.
Furthermore, such a ball extracting device must be convenient and easy to use as usually a golfer carries only the putter in hand at the end of the hole or, if not a that hole, the golfer carries another club and is separated from the golf bag. Therefore, it is necessary to have such a device that is built into the putter or club which, at the same time, does not effect the playing characteristics of the putter or club.
The prior art contains many devices designed to fulfill the above needs, but none does it like the present invention. The most pertinent patents concerning golf ball retrievers or extractors that attach to the handle-grip end of a golf club are as follows:
______________________________________ U.S. Pat. No.: Inventor: Date of Patent: ______________________________________ 5,004,240 Tsukamoto April 2, 1991 4,787,632 Nigrelli, et al. Nov. 29, 1988 3,318,628 White May 9, 1967 3,401,970 Russell Sept. 17, 1968 3,462,184 Russell Aug. 19, 1969 2,833,584 McEvoy May 6, 1958 2,801,875 McEvoy Aug. 6, 1957 802,264 Brown Oct. 17, 1905 3,698,720 Gudmundsen Oct. 17, 1972 3,273,927 Carlson Sept. 20, 1966 3,239,264 DuPont March 25, 1964 4,687,204 Lempio Aug. 18, 1987 1,380,526 Carpenter June 7, 1921 1,674,294 O'Rourke June 19, 1928 2,523,942 Ciambriello Sept. 26, 1950 2,750,222 Borah June 12, 1956 ______________________________________
The Tsukamoto patent shows an extractor will ball-retrieving prongs built into the grip handle. Unfortunately, the latter device requires that the golf club handle be modified so that a spring and other mechanical components can be placed therein to operate the retrieving prongs. The Nigrelli, et al. patent shows claw-clamp type retrievers that attach to the end of a club handle. The White patent shows another prong-like retriever built into the handle grip operable by a push button extension. The two Russel patents show other prong-like retrievers that attach to the end of a handle or which are built into the handle grip extension. The two McEvoy patents also show palm retrievers that are removably attachable to the handle by different means. The remainder of the above patents show various golf ball retrievers that fit by a collar over the end of the golf club or are incorporated within the handle grip itself.
Unlike the golf ball retrievers or extractors in the prior art that are attached to the handle end of the golf club, the present invention is an integral part of the grip itself and thus requires no modification of an existing golf club. Furthermore, unlike inventions in the prior art the present invention has no moving parts. The present invention discloses an extractor which is a circular module having an opening on the top end which holds a ball when it is pushed downward on the ball. The present extractor has one or more finger holes around the extractor to enable the ball to be released from the extractor by use of the golfer's fingers. One embodiment of the present invention has an entire grip that fits over the golf club shaft and replaces the preexisting grip on the golf club. Another embodiment is designed to fit over a preexisting grip. Finally, a third embodiment attaches just over the tip of the grip itself. All of the embodiments require no modification to existing golf clubs and have no impact upon putting or playing performance.


Proposed is a method of static scaling of an image in holographic lithography. The method consists of generating a final virtual digital hologram of the original pattern through a sequence of mathematical calculations with participation of a virtual coherent light source having a predetermined wavelength λ1 and producing an actual hologram on the basis of the virtual digital hologram of the original pattern. The obtained hologram can be used for forming an actual original pattern in a predetermined size. When it is necessary to produce the original pattern in another size, this can be done by static scaling by merely selecting another wavelength for the laser source with adjustable wavelength. The method allows determining the wavelength range in which scalability is possible with substantially homothetic transformation of the image.

Field of the Invention
The present invention relates to the semiconductor industry, in particular, to microlithography, and more specifically to a method of static scaling of an image in holographic lithography.
Description of the Related Art
Lithography and, in particular, photolithography is a well-known technique in semiconductor and printed circuit board (PCB) manufacture for creating electrical components and circuits. Predominantly, used for this purpose is projection photolithography, which involves projecting a mask image on the surface of a substrate, which has been covered by a layer of photoresist, before exposing both a mask and a substrate to light. As a rule, the projected image is optically reduced with a factor of 5 or more and for obtaining an image of high quality and accuracy the process dictates the use of very complicated, precision, and extremely expensive optical equipment operating in short wavelengths of ultraviolet range of spectrum, e.g., with λ of 193 nm or shorter. As a rule, the light sources used in the process are lasers.
The areas of photoresist that are exposed to light react and change chemical properties of the coating layer. The photoresist is then developed in order to remove either the exposed portions of photoresist for a positive resist or the unexposed portions for a negative resist. The pattern formed in the photoresist allows further processing of the substrate, such as, but not limited to, etching, deposition, or implantation.
At the present time, the above-mentioned projection photolithography is a basic photolithography technique used for production of integrated circuits. However, further development in the field of integrated circuit associated with demand for higher degree of integration and increase in complexity of the integrated circuits put forward the goals which in case of projection lithography leads to extraordinary material and intellectual expenditures.
One of practical problems of projection lithography is complexity of image scaling in sequential operations performed with the use of set of different masks. The scales of images produced with the use of masks installed in the same position of lithograph may have deviations that occur during the manufacture of the masks, even in the same process. Such deviations may be caused also by the use of different mask manufacturing tools, etc. The same relates to the alignment marks for registering positions of the mask in the lithograph.
In practical projection lithography, including the most advance lithography with the critical dimensions of image elements of the order of tens nanometers, the above problem is solved by microadjustment of the image scale by minutely displacing the mask in direction of the optical axis (in the Z-axis direction perpendicular to the image plane). In order to satisfy precision mask scaling requirements these displacements are carried out with the use of extremely complicated and expensive equipment since such an adjustment involves the use of a set of complicated micro-interferometric devices and tools for micronanopositioning. A provision of such an equipment in combination with the basic optical components of the system is a decisive factor in determining the manufacturing cost of the final product.
On the other hand, known in the art is so-called holographic lithography which to some extent is free of problems associated with the projection lithography. In holographic lithography the image formation process on a semiconductor substrate is carried out by restoring an image recorded on a special holographic mask with the use of a highly coherent laser light. The holographic mask per se is prepared by using special calculation procedures and is physically manufactured by technology which is close to the manufacture of mask in accordance with conventional projection lithography. It should be noted that the topology of the images of the holographic masks does not have anything in common with the mask topology used in the projection lithography where the mask image is similar to the original image. On the other hand, the use of the holographic masks provides significant advantages as compared to the masks of the projection lithography, i.e., the holographic masks may have several hundred longer lifetime than the masks of the projection lithography. Furthermore, defects of mask images in holographic mask practically do not affect the accuracy and quality of the target image. Another essential advantage of the holographic masks is simplicity of manufacture and low production cost. Furthermore, the topology of the holographic masks makes it possible to reproduce some image elements unattainable with the projection lithography technique.
However, until recent time the holographic lithography did not find practical application because methods for calculation of mask pattern suitable for practical application, even for masks of an average complexity, required so much time that it was practically impossible for actual application.
Nevertheless, attempts to solve the above problem of holographic lithography have been undertaken and even successfully accomplished as disclosed in the U.S. patent application Ser. No. 14/142,776 filed on Dec. 28, 2013 by Vadim Rakhovsky, et al. This application describes a method of manufacturing a holographic mask capable of producing an image pattern that contains elements of a subwavelength size along with decreased deviations from the original pattern. The original pattern is converted into a virtual electromagnetic field and is divided into a set of virtual cells with certain amplitudes and phases, which are mathematically processed for obtaining the virtual digital hologram. The calculation of the latter is based on parameters of the restoration wave, which is used to produce the image pattern from the mask, and on computer optimization by variation of amplitudes and phases of the set of virtual cells and/or parameters of the virtual digital hologram for reaching a satisfactory matching between the produced image pattern and the original pattern. The obtained virtual digital hologram provides physical parameters of the actual digital hologram that is to be manufactured.

Method of static scaling of image in holographic lithography


A real-time performance evaluation system can compare machine performance to a performance standard. A Fleet Operations Subsystem (FOS) can determine a machine status such as Parked, Idle, Working, Travel or Turning. The FOS can be configured to determine machine performance by determining the amount of time spent in each status. The performance can be compared to predetermined performance standards, for example a minimum number of hours spent working, or a maximum number of hours spent idle. A performance score can be generated based on the comparison. A report of the performance evaluation can be provided. A report can be in the form of a performance marker graphic on a visual display. The performance marker can represent the performance score. The performance marker can be in the form of an alarm symbol for a poorly performing machine. The system provides an operator or manager the opportunity to improve machine performance.

In the agricultural industry, there is a continual effort to increase operator and machine productivity while decreasing operational costs. Accordingly, farmers have embraced larger and more technically advanced machinery, more precise farming techniques and more automated technology to relieve machine operators of many of the tasks associated with cultivating and harvesting agricultural fields. Precision farming enables crop product to be applied under field-specific parameters to optimize and better predict yield based on the particular characteristics of the field. Properly employed, precision farming techniques can reduce product, operator and equipment costs. Similarly, automated guidance systems, relying on geo-positioning satellites for accurate location data, and on user input for designated tasks, can reduce operator error and fatigue, further mitigating costs.
However, while beneficial for assisting particular apparatus maneuvers, such systems may not address other costs and inefficiencies associated with agricultural operations, whether in the context of a particular vehicle and operator, or in the context of managing a fleet of vehicles.

Real-time evaluation of machine performance for fleet management