This invention relates to electromagnetic wave beam paths, formation of the beam, illumination of programmable electromagnetic wave field vector orientation rotating devices (“PEMFVORD”) with an electromagnetic beam, and the technique of projection of the modulated beam. This invention also relates to a unique light path and method of forming the light into a rectangular beam to be used for optical projection systems and, more particularly, in a color and/or black and white liquid crystal device (LCD) projectors that produce high resolution, high brightness and/or three-dimensional images. This invention further relates to a device capable of receiving and displaying two-dimensional and three dimensional images.

A disturbance (change in position or state of individual particles) in the fabric of space-time causes a sphere of influence. Stated in a simplistic manner, the action of one particle influences the actions of the others near it. This sphere of influence is referred to as a "field", and this field is designated as either electric or magnetic (after the way it influences other particles). The direction of travel of the particle is called the direction of propagation. The propagation of the particle, the sphere of influence, and the way it influences other particles is called an electromagnetic wave, and is shown in FIG. 1.
As shown in FIG. 1, the electric and magnetic fields are orthogonal (at right angles) to each other and the direction of propagation. These fields can be mathematically expressed as a vector quantity (indicating the direction of influence along with strength, i.e., magnitude, of influence) at a specific point or in a given region in space. Thus, FIG. 1A is the electromagnetic wave in FIG. 1, but with the view of looking down the axis of propagation, that is, down the x axis of FIG. 1. FIG. 1A shows some possible various electric field vectors that could exist, although it should be understood that any and all possible vectors can exist around the circle, each having different magnitudes.
Vectors can be resolved into constituent components along two axes. This is done for convenience sake and for generating a frame of reference that we, as humans, can understand. By referring to FIG. 1B, it is shown that the electric field vector E, can be resolved into two constituent components, E(y) and E(x). These quantities, then, describe the orientation and the magnitude of the electric field vector along two axes, the x and y, although other axes or systems could be chosen. The same applies to magnetic fields, except that the X and Z axes would be involved
The ways the electric and magnetic fields vary with time in intensity and direction of propagation have been determined by several notable mathematicians and physicists, culminating in a group of basic equations by James Maxwell. These equations, simply applied, state that a field vector can be of one of several different states, that is: 1) the field vector varies randomly over a period of time, or 2) the field vector can change directions in a circular manner, or 3) the field vector can change directions in a elliptical manner, or 4) the field vector can remain constant in magnitude and direction, hence, the field vector lies in one plane, and is referred to as planar.
This orientation of a field vector and the way it changes with time is called the state of polarization.
Electromagnetic waves can be resolved into separate electromagnetic waves with predetermined orientations of a field vector. The electromagnetic waves with a predetermined orientation of a field vector can then be directed through materials, such as a liquid crystal device, that is capable of changing (or altering) their orientation of the field vector upon application of an outside stimulus, as is demonstrated in FIG. 7. These devices are noted as programmable electromagnetic wave field orientation rotating devices (PEMFVORD).
An electromagnetic wave can be characterized by its frequency or wavelength. The electromagnetic spectrum (range) extends from zero, the short wavelength limit, to infinity, the long wavelength limit. Different wavelength areas have been given names over the years, such as cosmic rays, alpha rays, beta rays, gamma rays, X-rays, ultraviolet, visible light, infrared, microwaves, TV and FM radio, short wave, AM, maritime communications, etc. All of these are just short hand expressions of stating a certain range of frequencies for electromagnetic waves.
Different areas of the spectrum interact with electromagnetic influences upon them in various proportions, with the low end being more influenced by magnetic fields, and the high end being influenced by electric fields. Thus to contain a nuclear reaction, a magnetic field is used, while controlling light an electric field is used.
FIG. 2 illustrates a schematic cross section of an LCD cell. The LCD cell 100 includes a liquid crystal material 101 that is contained between two transparent plates 103, 104. Spacers 105, 106 are used to separate the transparent plates 103, 104. Sealing elements 107, 108 seal the liquid crystal material 101 between the transparent plates 103, 104. Conductive coatings 109, 110 on the transparent plates 103, 104 conduct the appropriate electrical signals to the liquid crystal material 101.
A type of liquid crystal material 101 used in most LCD cells for optical display systems is referred to as "twisted nematic." In general, with a twisted nematic LCD cell, the molecules of an LCD cell are rotated in the absence of a field through a 90° angle between the upper 103 and lower 104 transparent plates. When a field is applied, the molecules are untwisted and line up in the direction of the applied field. The change in alignment of the molecules causes a change in the birefringence of the cell. In the homogeneous ordering, the birefringence of the cell changes from large to small whereas the opposite occurs in the homeotropic case. The change in birefringence causes a change in the orientation of the electric field vector for the light being passing through the LCD. The amount of the rotation in the molecules for an individual LCD cell 100 will determine how much change in polarization (orientation of the electric field vector) of the light occurs for that pixel. The light beam is then passed through another component of the system (i.e., polarizer analyzer) and is resolved into different beams of light by the orientation of their electric field vectors, with the light that has a selected predetermined component of the electric field vector passing through to finally strike the screen used for the display.
A twisted nematic LCD cell requires the light incident at the LCD cell 100 to be polarized. The polarized light for a typical projector is generally derived from a randomly polarized light source that is collimated and then filtered by a plastic polarizer to provide a linear polarized beam. Linear polarized beams are conventionally referred to as being S-polarized and P-polarized with the P-polarized beam defined as polarized in a direction parallel to the plane of incidence and the S-polarized beam defined as polarized perpendicular to the plane of incidence.
The development of PEMFVORD technology has resulted in the development of LCD projectors which utilize one or more LCDs to alter the orientation of the electric field vector (see FIG. 7) of the light being projected. The birefringence of the individual LCD pixels is selectively altered by suitable apparatus such as cathode ray tubes, lasers, or electronic circuit means. A typical liquid crystal light valve (LCLV) projector includes a source lamp which is used to generate a light beam that is directed through a polarizer. This polarized light is directed through the LCDS to change the polarization according to the image to be displayed. The light, after exiting the LCD, passes through a plastic polarizer analyzer which stops and absorbs the unwanted portion of light. The formed image is then enlarged with a projection lens system for forming an enlarged picture on a display screen.
Color LCLV projectors typically include color separating apparatus such as a prism, beam splitters or dichroic mirrors to separate collimated white light beams from the light source into three primary color beams (i.e., red, green and blue beams). The red, green and blue beams are then individually modulated by LCDs and combined by separate optical apparatus such as combining prisms, mirrors or lenses.
In general, the quality and brightness of the projected image in any LCLV projector is a function of the brightness of the source for illuminating the LCDs and the polarizing means. Polarizing optics must be utilized to filter/separate the white light into light with a single orientation of the electric field vector. The white light emitted from the source is thus only partially utilized (i.e., one direction of polarization) in most LCLV projection systems. This requires oversized light sources to achieve a desired brightness at the viewing screen.
Typically, with a twisted nematic transmissive type LCD cell surrounded by plastic polarizers, only forty percent or less of the output of the light source is utilized. Practically, only a maximum transmission of 50% for randomly polarized light passed through could ever be achieved because of the construction and principles involved in plastic polarizers, allowing for 100% efficiency for the device for all wavelengths. Thus, it is impossible to obtain a full brightness projector. Moreover, the unused polarized component of the light source is absorbed by the plastic polarizers and generates wasted energy in the form of heat and transfers this heat to other components (i.e., LCDs, electronics, etc.) and hence is detrimental to the system (especially the plastic polarizers, LCDs, electronics, etc.). This heat must be either shielded and/or dissipated from the components of the system, or else, the light source must be reduced in light output so that the amount of light being absorbed is below the threshold of permanent damage to the components, including the plastic polarizers. Currently, this threshold for fabricated plastic polarizers is between the range of 5-10 watts of light per square inch (0.78-1.55 watts per square centimeter), depending upon the wavelength of the illuminating light. A method for improving the damage threshold is included in U.S. Pat. No. 5,071,234 to Amano, et al., although this patent does not discuss the particulars of what the damage threshold is.
Prior art systems have required relatively complicated optical systems including the use of polarizing prisms and prepolarizing prisms to ensure a unitary or single polarization at the LCD and to provide a suitable resolution and contrast of the projected image with prior art color LCLV projectors, complicated optic components and arrangements are required to combine the separated color bands at a suitable resolution and contrast.
Representative prior art LCLV projectors are disclosed in U.S. Pat. No. 5,060,058 to Goldenberg, et al., U.S. Pat. No. 5,048,949 to Sato, et al., U.S. Pat. No. 4,995,702 to Aruga, et al., U.S. Pat. No. 4,943,154 to, Miyatake, et al., U.S. Pat. No. 4,936,658 to Tanaka, et al., U.S. Pat. No. 4,936,656 to Yamashita, et al., U.S. Pat. No. 4,935,758 to Miyatake, et al., U.S. Pat. No. 4,911,547 to Ledebuhr, U.S. Pat. No. 4,909,601 to Yajima, et al., U.S. Pat. No. 4,904,061 to Aruga, et al., U.S. Pat. No. 4,864,390 to McKechnie, U.S. Pat. No. 4,861,142 to Tanaka, et al., U.S. Pat. No. 4,850,685 to Kamakura, U.S. Pat. No. 4,842,374 to Ledebuhr, U.S. Pat. No. 4,836,649 to Ledebuhr, et al., U.S. Pat. No. 4,826,311 to Ledebuhr, U.S. Pat. No. 4,786,146 to Ledebuhr, U.S. Pat. No. 4,772,098 to Ogawa, U.S. Pat. No. 4,749,259 to Ledebuhr, U.S. Pat. No. 4,739,396 to Hyatt, U.S. Pat. No. 4,690,526 to Ledebuhr, U.S. Pat. No. 4,687,301 to Ledebuhr, U.S. Pat. No. 4,650,286 to Koda, et al., U.S. Pat. No. 4,647,966 to Phillips, et al., U.S. Pat. No. 4,544,237 to Gagnon, U.S. Pat. No. 4,500,172 to Gagnon, U.S. Pat. No. 4,464,019 to Gagnon, U.S. Pat. No. 4,464,018 to Gagnon, U.S. Pat. No. 4,461,542 to Gagnon, U.S. Pat. No. 4,425,028 to Gagnon, U.S. Pat. No. 4,191,456 to Hong, et al., U.S. Pat. No. 4,127,322 to Jacobson, et al., U.S. Pat. No. 4,588,324, to Marie, U.S. Pat. No. 4,943,155 to Cross, Jr., U.S. Pat. No. 4,936,657 to Tejima, et al., U.S. Pat. No. 4,928,123 to Takafuji, U.S. Pat. No. 4,922,336 to Morton, U.S. Pat. No. 4,875,064 to Umeda, U.S. Pat. No. 4,872,750 to Morishita, U.S. Pat. No. 4,824,210 to Shimazaki, U.S. Pat. No. 4,770,525 to Umeda, et al., U.S. Pat. No. 4,715,684 to Gagnon, U.S. Pat. No. 4,699,498 to Naemura, et al., U.S. Pat. No. 4,693,557 to Fergason, U.S. Pat. No. 4,671,634 to Kizaki, et al., U.S. Pat. No. 4,613,207 to Fergason, U.S. Pat. No. 4,611,889 to Buzak, U.S. Pat. No. 4,295,159 to Carollo, et al. Prior art illumination systems for overcoming problems with the brightness of LCD display illumination systems have not been completely successful. Prior art illumination systems for overcoming problems with the brightness of LCD display illumination systems have not been completely successful.
An example of an illumination system that attempts to utilize the full output of a light source for increasing the brightness of an LCD display is disclosed in U.S. Pat. No. 5,028,121 to Baur, et al., In the Baur system, the randomly polarized light source is resolved into two separate polarized beams, with one of the polarized beams passed to a dichroic color splitter that then directs the segregated color beams to a set of reflecting LCDs, while the other beam of different polarization is sent to a different set of LCDs through a different dichroic splitter. After having each respective portion of the beams' electric field vector altered, the beam is then reflected back through the dichroic mirrors into the polarizing beam splitter/combiner. The picture to be represented is sent to the projection lens, while the rejected beam is sent back into the light source. This causes the light source to heat and have a shortened life span. Furthermore, each sequential field to be projected has a different brightness level illuminating each pixel, depending upon the amount of light that is rejected back into the light source.
For example, if a light source has an average output of 1000 lumens and the sequential field to be projected has an average brightness level of 30% then 700 lumens would be reflected back into the light source, making the light emitted from the source to be an effective 1700 lumens. In the next sequential field, if the average brightness level is 50% then 500 lumens would be reflected back into the light source, making the light emitted from the source to be effectively 1500 lumens. This can be alleviated by computing the average brightness level to be projected, and then modulating the brightness level of the light source when the field is changed for projection so that the illumination of a pixel is at a constant brightness. This system can further be modified by (or be a stand alone system) that would monitor the light output of the light source and change the driving circuitry of the light source to maintain a constant brightness level. This can be monitored by a light transducer that monitors the light from a beam splitter, or alternately, can be mounted directly on a LCD panel outside of the picture forming active area. However, the addition of any of the above circuitry further complicates the projector and makes the light source an active part of the system, increasing the cost and complexity of the projector.
Another example of an illumination system that attempts to utilize the full output of a light source for increasing the brightness of an LCD display is disclosed in U.S. Pat. No. 4,913,529 to Goldenberg, et al. In the Goldenberg system, a beam of light, from a light source, is split into two orthogonally linear polarized beams. One of the beams is then passed through a device that rotates one of the beams to change its direction of polarization so that there are two beams of the same polarization. The beams of the same polarization are then directed through different faces of a prism, combined by the prism and focused on the LCD devices.
A problem with such a system is that the beams are not collinear. The beams illuminate the polarizer at different angles, causing an area of usable light, and another area of unusable light. The result is that all of the light available is not used. Another obstacle is that it is difficult to align the combined beams with the use of a prism. Yet another complication is that the prism tends to separate the light into separate colors. This detracts from the clarity, brightness and limits the resolution of the projected image. Still another complication is that the performance of polarizers vary with the angle of light illuminating them, causing different polarizations and different color gradations to occur in the beam.
Other systems, such as those disclosed in U.S. Pat. No. 4,824,214 to Ledebuhr, U.S. Pat. No. 4,127,322 to Jacobson, et al., U.S. Pat. No. 4,836,649 to Ledebuhr, et al., and U.S. Pat. No. 3,512,868 to Gorklewiez, et al. also disclose optical layouts for achieving a high brightness in display systems that utilize LCD devices. In general, these systems are relatively complicated and contain numerous components that are large, expensive, and difficult to adjust.
Representative prior art flat fluorescent light sources are disclosed in U.S. Pat. No. 4,978,888 to Anandan, et al., and U.S. Pat. No. 4,920,298 to Hinotani, et al.
Representative prior art light integrators for light sources are disclosed in U.S. Pat. No. 4,918,583 to Kudo, et al., U.S. Pat. No. 4,787,013 to Sugino, et al., and U.S. Pat. No. 4,769,750 to Matsumoto, et al.
Various prior art techniques and apparatus have been heretofore proposed to present 3-D or stereographic images on a viewing screen, such as on a polarization conserving motion picture screen. See U.S. Pat. No. 4,955,718 to Jachimowicz, et al., U.S. Pat. No. 4,963,959 to Drewio, U.S. Pat. No. 4,962,422 to Ohtomo, et al., U.S. Pat. No. 4,959,641 to Bess, et al., U.S. Pat. No. 4,957,351 to Shioji, U.S. Pat. No. 4,954,890 to Park, U.S. Pat. No. 4,945,408 to Medina, U.S. Pat. No. 4,936,658 to Tanaka, et al., U.S. Pat. No. 4,933,755 to Dahl, U.S. Pat. No. 4,922,336 to Morton, U.S. Pat. No. 4,907,860 to Noble, U.S. Pat. No. 4,877,307 to Kalmanash, U.S. Pat. No. 4,872,750 to Morishita, U.S. Pat. No. 4,870,486 to Nakagawa, U.S. Pat. No. 4,853,764 to Sutter, U.S. Pat. No. 4,851,901 to Iwasaki, U.S. Pat. No. 4,834,473 to Keyes, et al., U.S. Pat. No. 4,807,024 to McLaurin, et al., U.S. Pat. No. 4,799,763 to Davis, U.S. Pat. No. 4,772,943 to Nakagawa, U.S. Pat. No. 4,736,246 to Nishikawa, U.S. Pat. No. 4,649,425 to Pund, U.S. Pat. No. 4,641,178 to Street, U.S. Pat. No. 4,541,007 to Nagata, U.S. Pat. No. 4,523,226 to Lipton, et al., U.S. Pat. No. 4,376,950 to Brown, et al., U.S. Pat. No. 4,323,920 to Collendar, U.S. Pat. No. 4,295,153 to Gibson, U.S. Pat. No. 4,151,549 to Bautzc, U.S. Pat. No. 3,697,675 to Beard, et al., In general, these techniques and apparatus involve the display of polarized or color sequential two-dimensional images which contain corresponding right eye and left eye perspective views of three-dimensional objects. These separate images can also be displayed simultaneously in different polarizations or colors. Suitable eyewear, such as glasses having different polarizing or color separating coatings, permit the separate images to be seen by one or the other eye. This type of system is relatively expensive and complicated requiring two separate projectors and is adapted mainly for stereoscopic movies for theaters. U.S. Pat. No. 4,954,890 to Park discloses a representative projector employing the technique of alternating polarization.
Another technique involves a timed sequence in which images corresponding to right-eye and left-eye perspectives are presented in timed sequence with the use of electronic light valves. U.S. Pat. No. 4,970,486 to Nakagawa, et al., and U.S. Pat. No. 4,877,307 to Kalmanash disclose representative prior art stereographic display systems of this type.
While previous time sequential light valve systems are adaptable to display arrangements for a television set, because of problems associated with color, resolution and contrast of the projected image, they have not received widespread commercial acceptance. Moreover, the systems proposed to date have also been relatively expensive and complicated.

This patent is subject to a terminal disclaimer.

High efficiency electromagnetic beam projector, and systems and methods for implementation thereof


A data storage device including, in one implementation, a NAND memory and a controller. The NAND memory includes a read/write circuit configured to determine and store initial physical column addresses for each plane included in the NAND memory. The controller is configured to send a read-transfer command and a one-byte address to the NAND memory. The read/write circuit is also configured to retrieve a first initial physical column address from the initial physical column addresses stored in the NAND memory after the NAND memory receives the one-byte address from the controller. The first initial physical column address is associated with a die address and a plane address included in the one-byte address. The read/write circuit is further configured to retrieve a first set of data stored at the first initial physical column address. The read/write circuit is also configured to output the first set of data to the controller.

This application relates generally to memory devices, and more particularly, to a controller and NAND memory that reduce execution time of data transfer operations, for example, by pre-calculating initial column addresses.
Data transfer protocols between controllers and NAND memory involve a significant number of command and address cycles as well as a wait time between command/address cycles and data transfer. Command and address cycles are required to be issued using legacy input/output ("I/O") speed and protocol. Data bytes, however, can be issued using toggle mode speeds. With every new generation of NAND memory, toggle mode speed scales by approximately 50%. Command/address speed, however, does not scale with toggle mode speed. As a result, command/address cycles add a significant overhead for memory devices that use higher toggle mode speeds.

Overhead reduction in data transfer protocol for NAND memory


An optical element for controlling light propagation including: transparent material; and inorganic fine particles dispersed in the transparent material, wherein the transparent material and the inorganic fine particles meet at least one of following a) and b): a) a rate of change of a refractive index of the transparent material with temperature and a rate of change of a refractive index of the inorganic fine particles with temperature are opposite in sign; b) a thermal expansion coefficient of the transparent material and a thermal expansion coefficient of the inorganic fine particles are opposite in sign.

1. Field of the Invention
The present invention relates to an optical element suitably used for a lens, a filter, a grating, an optical fiber, a planar optical waveguide, and the like. In particular, the present invention relates to an optical element whose refractive index does not change with temperature.
2. Description of Related Art
An optical element such as a lens, a filter, a grating, an optical fiber and a planar optical waveguide is formed of transparent material as an optical element for controlling a mode of light propagation such as transmission, reflection, refraction, and diffraction in modern society. Transparent inorganic materials such as silicic glass materials and metallic oxides are in widespread use as transparent material. Whereas, in recent years, transparent organic polymers with superior moldability, economy, and lightweight properties have also become widespread, and have come into practical use as lenses for spectacles, objective lenses for optical disk, plastic optical fibers, polymer planar optical waveguides, and the like. For example, there is some description in Fumio Ide, "Optoelectronics and Polymeric Material" Kyoritsu Shuppan (1995).
As for the transparent inorganic materials and transparent organic polymers, their refractive indexes, however, change with temperature. Therefore troubles often occur in the case of using them for optical elements generically referred to as lenses for an optical disk device, such as CD and DVD, trying to improve performance of the device by focusing light down to focusing limit (diffraction limit), and optical fibers and planar optical waveguides in which light propagates over a long distance. In particular, as for diffractive optical elements such as Bragg gratings used for optical communications and optical sensors, it is known that performance of the elements is deteriorated significantly because change of the refractive index causes change of the grating constant (optical distance equivalent to grating interval).
Conventionally, various methods have been proposed as a method for making the refractive index of transparent material temperature-independent (athermalizing). For example, in the case of a planar optical waveguide 4 illustrated by FIG. 1D, the following method that the waveguide 4 is constructed in such a way that the thermal expansion coefficient of material constituting an optical waveguide layer 4a and the thermal expansion coefficient (linear expansion coefficient) of material constituting a substrate 4b are opposite in sign, and the waveguide 4 is athermalized by compensating for change of the refractive index of the waveguide layer 4a due to temperature change, is proposed. As examples of the above method, Yasuo Kokubun, "Technology for Making Optical Circuit Independent of Temperature", Applied Physics, Vol. 66, pp. 934 (1997) and JP-Tokukai-2000-352633A are taken.
Alternatively, when a fiber Bragg grating is used, the method of supporting and packaging the fiber Bragg grating with a material having a thermal expansion coefficient opposite in sign to a silicic material constituting the fiber Bragg grating to compensate for thermal expansion of the silicic material is proposed. For example, A. Sakamoto et al., "IEICE Transactions on Electronics", Vol. E-83C, pp. 1441 (2000).
As a method for athermalizing transparent material itself instead of compensating by auxiliary material like this for temperature-dependent change of the refractive index of transparent material constituting an optical element, the method of doping transparent material with a material having a rate of change of the refractive index with temperature opposite in sign to the rate of change of the refractive index of transparent material with temperature is known. Methods like this are described in, for example, JP-Tokukai-2001-141945A and JP-Tokukai-2002-020136A.
However, methods like this are limited essentially to materials wherein a silicic glass material is doped with boron oxide as shown in the above-described gazettes. The methods do not make such widespread applications possible, as inorganic transparent materials except silicic glass and transparent materials composed of an organic polymer.
Furthermore methods of obtaining athermalized material by forming mixture or complex composed of two materials whose rates of change of the refractive indexes with temperature are opposite in sign are proposed. As an example of methods like these, the method described in JP-Tokukai-2001-201601A is taken. However as for this method, because of using means that organic material is mixed into inorganic glass material practically, there is a problem that phase separation of the inorganic material and the organic material occurs, and light scattering on phase separation interface undermines optical transparency. Suppression of this problem must rely on sol-gel method in which organic-inorganic complex is formed as starting material and then is heat-treated, as shown in the above-described gazette. In this case, there is a problem that it becomes difficult to apply this method to forming optical elements requiring high dimensional accuracy because of significant change in volume accompanying condensation polymerization in a molding process of optical elements.
As above, various methods are proposed as a method for forming athermalized optical elements. And yet problems remain, such as auxiliary material except transparent material forming an optical element is required, material series forming an optical element is limited, decrease of the transparency accompanying light scattering occurs, and dimensional distortion in a step for forming an optical element occurs.


An apparatus may include circuitry configured to control reproduction, at a head-mounted display device, of content, based on a determination of importance of an event occurring around the head-mounted display device.

An image display device which is used to view an image by being worn on a head or a face, that is, a head-mounted display, has been generally used. In the head-mounted display, for example, an image display unit is disposed for each of the left and right eyes, and an enlarged virtual image of a displayed image is formed by a virtual image optical system, and thereby a user can observe an image with a sense of reality. Popularity of the head-mounted display is very high. As mass production proceeds from now on, every person might come to have one head-mounted display as cell phones, smart phones, and hand held game machines have spread.
The head-mounted display is equipped with display panels of high resolution made of, for example, a liquid crystal or an organic Electro-Luminescence (EL) element and the like as display units for the left and right eyes. In addition, the head-mounted display can be classified into a light-shielding type and a permeable type. The light-shielding head-mounted display is configured to directly cover the eyes of a user when worn on a head, and a sense of immersion is increased when the user views an image. A display screen is photographed in an enlarged manner using a virtual image optical system and is observed by a user as an enlarged virtual image which is at an appropriate angle of view, and it is possible to reproduce a sense of reality such as that when viewing in a movie theater when multi-channels are reproduced in a headset (for example, refer to PTL 1). On the other hand, in case of a transmitting head-mounted display, a user can view (that is, see-through) an external landscape over an image while wearing the head-mounted display and the image is displayed (for example, refer to PTL 2).
Whichever type between the light-shielding type and the permeable type the head-mounted display is, the head-mounted display draws a user wearing the head-mounted display into a virtual world. Therefore, it is of concern that sight and hearing of the user are slow to respond to the oat side world.
For example, a sight device which includes a function of stopping an image when an emergency button provided in a remote controller is pressed, and can be worn on a head has been proposed (for example, refer to PTL 3). However, a user of the sight device has to determine whether to stop an image or not by pressing the emergency button himself. That is, the user has to care about what is happening in the outside world while viewing an image, and receives interference from the real world, and a degree of immersion in a virtual world displayed by the sight device is lowered. Furthermore, if observing the outside world by pressing the emergency button to stop an image, there is an errand which is not important, thereby causing a disturbance in viewing an image.
In addition, a mounted display device which occupants of a car wear on the face to use is a device configured to detect an emergency state of the car, and detects a state in which a posture of the occupant becomes unstable or dangerous when a brake pedal is suddenly stepped on, steering is suddenly turned off, and the car collides with and rear-ends an object during a movement of the car as an emergency state to allow an outside world to be seen the detected emergency state has been proposed (for example, refer to PTL 4).
Moreover, an image display device which is worn on a face of a user and is equipped with a predetermined sensor to allow the outside world to be seen by instantly opening a shielding unit by a sudden movement, or an impact or a sound caused by an external factor has been proposed (for example, refer to PTL 5).

Controlling reproduction of content in a head-mounted display


Systems and methods for filling panoramic images having valid and invalid pixel regions are provided. An invalid region is identified in an initial panoramic image. Pixel data of invalid pixels in the initial panoramic image are replaced with pixel data of pixels from a valid region in at least one nearby panoramic image to obtain a valid fill region.

1. Field of the Invention
The present invention relates generally to panoramic imaging.
2. Background Art
A panoramic image has image data over a relatively wide angle of field of view of a scene. Panoramic images are increasingly being used to enrich a user experience in a wide variety of applications. For example, mapping services, terrain rendering services, photosharing services, web sites, and other services or applications are increasingly displaying panoramic images to users.
Creating panoramic images with valid data throughout an image area, however, can be difficult given the wide angle field of view. Obstructions or other undesirable objects may partially occlude a field of view. This is especially likely in certain panoramic images where one or more cameras are used to capture a wide angle field of a view of a scene. For example, to capture street-level imagery, multiple cameras aimed in different directions may be used to capture individual images of a scene. These individual images then are combined to create a panoramic image. Depending upon the particular camera arrangement, certain areas may be obstructed or not of interest. These areas can lead to invalid pixel data being present in a panoramic image. For example, in a situation where cameras are mounted on a moving vehicle to capture high-resolution images of a surrounding street scene, certain portions of the images near the ground may be blocked by a camera part or housing, or the vehicle itself, or may include the portions of vehicle when the vehicle is not of interest compared to the street-level imagery.
Photo editing applications, such as, Adobe Photoshop available from Adobe Systems Inc., allow images to be modified by a user to change pixel data and improve the user experience for a user viewing the modified image. However, these photo editing applications require significant time and effort by a user to manually identify and change invalid pixel data. Such photo editing applications are designed for general use and not equipped to handle a large volume of panoramic images.


A system includes a plurality of devices that are connected in series and a controller that communicates with the devices. Each of the devices has a plurality of input ports and corresponding output ports. The outputs of one device and the inputs of a next device are interconnected. The controller is coupled to the first device and the last device of the series-connection. The controller applies a test pattern to the plurality of input ports at the first device connected in series, by the controller. Each data channel defines a data path between corresponding pairs of input and output ports of the first and last devices. A data channel is enabled if the test pattern is detected at its corresponding output port.

Semiconductor memory devices are important components in presently available industrial and consumer electronics products. For example, computers, mobile phones, and other portable electronics all rely on some form of memory for storing data. While many memory devices are typically available as commodity devices, the need for higher integration has led to the development of embedded memory, which can be integrated with systems, such as microcontrollers and other processing circuits.
Unfortunately, the density of commodity memory cannot match the ever-increasing demand for memory. Hence multiple commodity memories are used together to fulfill the system memory requirements. Multi-device memory systems can be implemented as a set of silicon chips grouped together in a single package (called a multi chip system-MCP), or a multiplicity of memory device packages grouped together on a printed circuit board.
More often, the multi-device memory systems employ, non-volatile devices, such as flash devices, for storage. Demand for flash memory devices has continued to grow significantly because these devices are well suited in various embedded applications that require non-volatile storage. For example, flash is widely used in various consumer devices, such as digital cameras, cell phones, USB flash drives and portable music players, to store data used by these devices. Market demand for flash memory has led to tremendous improvements in flash memory technology over the past several years both in terms of speed and density.
Some flash devices employ serial interfaces such as, for example, multiple flash devices, which are used to perform operations, such as read, write and erase operations, on memory contained in the devices. A system of devices connected in series has input ports in the first device and output ports in the last device as shown in FIG. 1. Data is serially transferred from the input ports in the first device to the output ports in the last device. The configuration of the series-connected devices shown in FIG. 1 will be discussed in detail below.
Those skilled in the art understand that multi-device systems are tested at the individual component level and at the system level to ensure robustness of operation. In particular, memory devices are tested at the chip level to ensure that their memory cells are not defective. A defective memory cell is one that does not store data properly, due to fabrication defects or other defects that may occur during fabrication or assembly of the memory device.
Although each device is tested through functional and DC test steps at wafer-level and package level to screen out the device with defects on memory or logic blocks, it is difficult to find which devices have failed once they are mounted on the system board after packaging with stacked devices in a series-connection configuration. In conjunction with this problem, if there were any single failed device in the system of devices connected in series, all devices on the connection would be shown as defective devices due to data transmission failure caused by the failed device.
Typically, a fault in any single pin or in the interconnection between devices in the system of devices connected in series causes all devices to be judged as "failed" and no more testing is possible. Needless to say that the cost of stacked devices is much higher than the cost of a single device, and even good devices without any faults could be thrown away, or a system board with these devices may be replaced with a new one.

Data channel test apparatus and method thereof


A method of applying one of several resource distribution algorithms to an incoming call to a communication system. The applied resource distribution algorithm is based on resource parameters obtained from a main scheduler of the communication system. Some of the resource parameters include the type of call, the resource usage and the resource allocation scheme. The resource parameters generally describe the amount of resources that are currently being used by the system and which resources are available to the incoming call. The method of the present invention admits the incoming call to the communication system in accordance with one of the resource distribution allocation schemes. In this manner, the resources of the communication system can be efficiently and fairly distributed to different types of users requesting admission to the communication system.

1. Field of the Invention
This invention is generally related to communication systems and in particular to wireless communication systems.
2. Description of the Related Art
Communication systems, and in particular, wireless communication systems usually have limited amounts of various resources that can be allocated to users of such systems. Examples of resources include the amount of power allocated to a signal to be transmitted, the amount of bandwidth allocated to a particular signal and the rate at which data is transmitted for a particular signal. As users request admission to a communication system, the system will admit the users if there are sufficient resources available to adequately service the requesting users. Requesting users typically specify to the communication system the type and amount of resources they desire. Requesting users (or user equipment) usually utilize one or more signaling channels to communicate their resource specifications to the communication systems.
Hereinafter, the terms 'user' and 'user equipment' will be used interchangeably. The resource specifications are typically various parameters (e.g., data rate, transmit power, bandwidth) that the user equipment (e.g., cellular telephone, wireless pager, wireless personal computer) transmit to the system equipment to allow the system equipment to determine whether there are sufficient resources available to properly service the requesting user equipment. The system equipment are typical communication equipment (e.g., transmitters, radios, amplifiers, modulators, processors) used in wireline or wireless communication systems. The system equipment are typically owned, operated and controlled by a service provider. The service provider is usually a commercial entity (e.g., local phone company, cable company, Internet service provider) that provides communication services to users. The signaling channels are communication channels reserved by the system for controlling communications between users and between users and system equipment. Various signaling information are conveyed (i.e., transmitted and/or received) between system equipment and user equipment over the signaling channels to properly initiate, maintain and terminate communications between users or communications between user equipment and system equipment.
The signaling channels are operated as per one or more protocols established from one or more standards with which the communication system complies. Protocols are specific rules that dictate how communications between users or communication between user equipment and system equipment are to be managed. Typically, a communication system admits users requesting admission or schedules users on a First Come First Serve (FCFS) basis. Admission to the communication system is the procedure taken by the system to allow a user to have access to and utilize various resources of the system so as to initiate and establish communications with system equipment or with other user equipment via the system equipment. Requesting users are put in a queue in the time order of their request and each is admitted to the system upon its turn if there are sufficient resources available to serve such user. When there aren't sufficient resources for the next requesting user, the system does not admit the requesting user until the sufficient amount of resources becomes available. Thus, a requesting user may have to wait in the queue for a relatively long period of time before it is admitted to the system. Further, one or more other users in the queue may have resource requirements that can be met by the current amount of resources available, but these users are not admitted because it is not their turn to be served; in this manner, the FCFS scheduling technique renders the system inefficient.
Many times, the type of information being conveyed (i.e., transmitted and/or received) by users of the system warrants the use of a scheduling technique other than the FCFS technique. For example, the nature of voice calls using Voice over IP (Internet Protocol) infrastructure is such that the application of the FCFS may lead to low quality voice communications. Further, in third generation wireless communication system (e.g., systems that comply with the 3G-1X Code Division Multiple Access (CDMA) standard), gradations of available resources are made available. For example, in 3G-1X systems, the data rate resource is divided into lower speed channels and higher speed channels for data calls. Data calls are communications established between two users or between user equipment and system equipment where the information being conveyed is data (e.g., digital data) that represent graphics, text, video or any other type of information. Voice calls are established communications between user equipment or between user and system equipment that convey mainly voice signals. In many instances the voice signals are represented as digital information. Voice calls are characteristically distinct from data calls in that data calls are usually time-delay tolerant. Any interruption in the flow of bits for voice traffic signals during an established communication (i.e., a call) would cause discernible noise and in some cases may even make the voice quality unacceptable at a receiving end. Established communications are arrangements and procedures that are implemented as per the protocol and/or standard being followed by the communication system to allow communication signals to be conveyed between system equipment and/or user equipment. What is therefore needed is a technique for efficiently allocating resources to different types of calls by users of a communication system.

Voice and data call admission policies for a wireless communication system


The invention is a 2'-O-(4-benzoyl)benzoyl nucleoside 3', 5'-cyclic monophosphate of formula (I) ##STR1## wherein R' is guanine or adenine. Also disclosed are topical pharmaceutical compositions and methods of using them for reducing intraocular pressure.

1. Field of the Invention
The present invention concerns 2'-0-(4-benzoyl)benzoyl nucleoside cyclic monophosphate and the use of the same as to reduce intraocular pressure
2.Background of the Invention
The first report of benzoyl benzoyl derivatization was of the peptide hormone gastrin. This compound is unrelated to cyclic nucleotides and was employed as a photoaffinity probe for the gastrin receptor (R. E. Galardy, L. C. Craig, J. D. Jamieson and M. P. Printz, J. Biol. Chem., 249, 3510, (1974)). Benzoyl benzoyl derivatives of adenosine 5'triphosphate (ATP) (N. Williams and P. S. Coleman, J. Biol. Chem., 257, 2834-2841, (1982)), cytidine triphosphate (CTP) (C. Abeijon, J. M. Capasso, D. Tal, W. F. Vann and C. B. Hirschberg, J. Biol. Chem., 261, 11374-11377, (1986)) and uridine 5'triphosphate (UTP) (C. Abeijon et al, supra) were subsequntly reported. In each of these nucleotide triphosphates, the benzoyl benzoyl moiety was added at the 3'position. Fluorobenzoyl adenosine 5'triphosphate has been synthesized, but the fluorobenzoyl moiety was added to the N.sup.6 position on the base.
Derivatives of 3',5'cyclic guanosine monophosphate (cGMP) and 3',5'cyclic adenosine monophosphate (cAMP) which are useful as photoaffinity agents have been synthesized. Such derivatives differ from the inventive compounds herein in either the nature or location of the substituent moieties added. A thorough treatment of photoaffinity labelling compounds can be found in Methods of Enzymology, Vol. XLVI, (1977), Academic Press, N.Y., eds. W. B. Jakoby and Meir Wilchek. Some examples of these kinds of compounds are 8-azido derivatives of both cAMP and cGMP (B. E. Haley, Biochemistry, 14, 3852, (1975) and B. E. Haley, Methods in Enzymology, XLVI, 339-346, (1977)) and methylanthraniloyl addition to the 2'position of cGMP and cAMP (T. Hiratsuka, J. Biol. Chem., 257, 11354-13358, (1982)). Two fluorescent analogs of cAMP, 1,N-etheno-cAMP (J. A. Secrist, III, J. R. Barrio, N. J. Leonard, C. Villar-Palasi and A. G. Gilman, Science, 177, 279-280, (1972)) and 1,N-etheno-aza-cAMP (K. C. Tsou, K. F. Yip and L. W. Lo, Anal. Biochem., 60, 163-169, (1974)) have been reported, however, both analogs have altered adenine ring structures.
None of the above described heretofore reported compounds have been employed as therapeutic agents for the treatment of glaucoma or any other medical condition.

2'-O-(4-benzoyl)benzoyl nucleoside cyclic monophosphate


A motor driving apparatus comprises: an AC/DC converter which converts AC voltage supplied from an AC power source into DC voltage through PWM switching control of a power switching device; and a DC/AC converter which converts the DC voltage into variable-frequency AC voltage for driving a motor in a controlled manner. The AC/DC converter includes: a control unit which generates, based on an error between the DC voltage and a DC voltage command value, a PWM signal for the PWM switching control of the power switching device; and a frequency/gain varying unit which sets the frequency of the PWM signal to be generated by the control unit and a control gain in the control unit higher than their normal levels during a period in which a load in the DC/AC converter varies.

1. Field of the Invention
The present invention relates to a motor driving apparatus having a function for regulating DC link voltage by regulating control in an AC/DC converter when the load for a DC/AC converter changes suddenly during acceleration/deceleration of a motor.
2. Description of the Related Art
In a motor driving apparatus for driving a machine tool, industrial machine, robot, or the like, a method (a PWM converter method) may be employed that converts the waveform of an input current to a substantially sinusoidal waveform by applying PWM control, using a power switching device, to an AC/DC conversion operation for converting an AC voltage to a DC voltage.
The PWM converter method has the advantages of drastically reducing harmonics of the input current by increasing the PWM switching frequency and producing a variable DC output voltage.
Japanese Unexamined Patent Publication No. H10-257773 (JP10-257773A) discloses a technique for regulating the DC output voltage of a PWM converter apparatus by correcting the value of the integral term of a current command value so that the current command value becomes zero when the DC output voltage reaches an upper limit voltage value.
On the other hand, Japanese Unexamined Patent Publication No. H08-149855 (JP8-149855A) discloses a technique for suppressing variation in the DC link voltage due to a sudden change in load by making provisions to supply a motor speed command value to an AC/DC converter before supplying it to a DC/AC converter.
However, as described in Japanese Unexamined Patent Publication No. H10-257773 (JP10-257773A), the PWM converter method has the disadvantage that, during motor acceleration/deceleration, the output DC voltage (DC link voltage) changes and becomes unstable as the load in the AC/DC converter changes suddenly.
One possible approach to addressing this problem is to increase the loop gain, such as a voltage control gain or current control gain, thereby increasing the response of PWM control and enhancing the stability of the DC link voltage. In this case, the PWM switching frequency is also increased, because if the gain were simply increased, the control loop would oscillate. However, since the temperature of the power switching device rises in proportion to the increase in PWM switching frequency, it is not always possible to maintain the high PWM switching frequency for a prolonged period of time.
An object of the present invention is to provide a motor driving apparatus having a function that can regulate the DC link voltage while suppressing temperature rise in the power switching device.

Motor driving apparatus having DC link voltage regulating function


An organic light emitting display (OLED) screen and a terminal related to the field of terminal technologies, where the OLED screen includes an encapsulation layer and a substrate disposed below the encapsulation layer, in a first part of the OLED screen, the encapsulation layer is bonded to the substrate, and in a second part of the OLED screen, the OLED screen further includes a light emitting layer, where the light emitting layer is disposed between the encapsulation layer and the substrate, and the light emitting layer includes red light emitting pixels, green light emitting pixels, and blue light emitting pixels.

Full-screen displays have become a development trend of current mobile phone screen display technologies. Because space needs to be reserved for a front-facing camera in a display region of a screen, manufacturers are currently unable to produce a full-screen mobile phone in a real sense.
For example, a drilling solution is used in the prior art, to dispose a front-facing camera on a front panel of a mobile phone. Referring to FIG. 1a, the drilling solution means that a small hole 02 is drilled in a mobile phone screen 01 and a camera 03 is disposed inside the small hole 02. In this way, the rest region other than the small hole 02 on the screen 01 can be used for the mobile phone to display a graphical user interface (graphical user interface, GUI), for example, information, an image, and various menus provided for a user by the mobile phone.
Mobile phone screens may mainly include liquid crystal display (liquid crystal display, LCD) screens and organic light emitting display OLED screens. The OLED screen usually uses an organic light emitting material as a light emitting layer, which is capable of self-luminance, and has advantages such as low power consumption and fast response, obtaining increasing attention.
For the OLED screen, when the drilling solution shown in FIG. 1a is used, a sectional view of an OLED screen 01 shown in FIG. 1c may be obtained based on a section line 001 shown in FIG. 1b. In FIG. 1c, 011 represents a common layer (common layer) made of an organic material, 012 represents an encapsulation layer (encapsulation layer), and 013 represents a substrate (substrate). Because the organic material is likely to absorb substances such as moisture and gases, in the small hole 02 shown in FIG. 1c, harmful substances (denoted by circles in FIG. 1c) such as moisture and harmful gases (for example, oxygen) in air are likely to enter the inside of the OLED screen 01 through the common layer 011 made of the organic material, and consequently, for example, light emitting pixels of the OLED screen 01 become dark, affecting performance and service lives of the OLED screen 01 and the mobile phone.

Organic light emitting display OLED screen and terminal


Embodiments include a vehicle comprising an end facing an external object, at least one vehicle light positioned adjacent to the end and projecting a light pattern onto the object, a window adjacent to the end, and at least one proximity indicator coupled to the window at a predetermined position corresponding to an expected location of the light pattern on the object when the end is located a predetermined distance from the object. The proximity indicator can be removably adhered to the window. The light pattern can be visible through the window from a vehicle interior. In some embodiments, the object is positioned adjacent to a rear end of the vehicle and the at least one vehicle light is a rear vehicle light. In other embodiments, the object is positioned adjacent to a front end of the vehicle and the at least one vehicle light is a front vehicle light.

Currently, there are a number of different parking guidance systems for guiding a driver while parking a vehicle. For example, some vehicles include an onboard proximity detection system that audibly warns the driver, using short "beeps" or other sounds, as the vehicle approaches a wall or other object behind the vehicle. In some cases, the warning sounds change, for example, in frequency and/or pitch, in order to indicate the amount of space remaining between the vehicle and the object and/or to convey a stronger or more urgent warning as the remaining space decreases. However, one drawback of such proximity detection systems is that the warning sounds can be difficult to translate into a distance in terms of feet or inches. Also, the proximity detection equipment may not be available in certain (e.g., economy-level) vehicles.
Some vehicles include one or more cameras for capturing video of a rear (or front) of the vehicle and a display within the vehicle for displaying the captured video in real time. Using the live video feed, the driver can directly observe the space behind (or ahead of) the vehicle while moving the vehicle into a parking spot. However, one drawback of such video-based parking systems is the need for expensive equipment (e.g., camera(s), display screen, etc.) and complex circuitry, features that are not available in certain vehicles and/or are not feasible at certain price points.
Other existing parking systems include laser beams that are installed at predetermined points on the vehicle and projected onto either a forward or rearward surface adjacent to a parking spot. A position of the laser beams on the surface can indicate the distance between the vehicle and the surface and can help guide the driver into the spot. For example, in one system, a vertical line is applied to the rearward surface, and alignment of the laser beams on the vertical line indicates that the vehicle is properly positioned within the parking spot. However, such laser-based systems have several drawbacks. For example, laser beams can be extremely difficult to observe in bright sunlight conditions, and their performance may be affected by temperature changes and other external factors. Also, implementation of such systems can be costly and complex.
Accordingly, there still exists a need for an effective parking guidance system that can help drivers ascertain a distance between a vehicle and a wall or other object within a path of the vehicle and does not require expensive equipment or complex installation.


The present invention relates to a method of determining a constituent of a sample and more specifically, to a method of correcting an absorbance value for a spectrometer. The method is especially applicable in connection with spectrometric analysis instruments for quantitatively determining the chemical composition of fluids, e.g. the content of fat, protein lactose or urea, in food products, especially in raw milk or dairy products. The method is based upon a measurement of one or more selected ranges of a spectrum, providing an absorption spectrum of the product. The method may be applicable in connection with all spectroscopic instruments giving rise to specific ranges of a spectrum, such as UV, VIS, NIR, IR, NMR, MS, etc.). Typically, the spectrum will be a MID-IR absorption spectrum.

The method is specifically intended for filter-based spectrometers, which typically comprises an infrared light source, and an infrared detector, and there between a number of optical filters, which may be inserted into the optical light path. A sample measurement cell comprising two glass plates defining a storage space therein between for storage of a sample to be analysed, is arranged between the light source and the detector. During use, the cell is filled with the sample e.g. milk, and the light transmitted from the light source through the sample is detected.
Typically, the concentration of the constituent e.g. of fat in milk is determined by use of a number of specific filters from the absorbance in the milk sample measured relative to a reference, such as a reference sample, e.g. a sample of pure water. This is a well-known technique, e.g. as described in U.S. Pat. No. 4,236,075, which has been applied for analysis of food products for more than 20 years.
The analysis of milk is now increasingly being carried out by use of FTIR instruments covering a broad frequency range of the IR spectrum, c.f. international patent application No. PCT/DK96/00068 published as WO 96/24832. The measured spectra of a plurality of known samples are used to let the instrument "learn" how to interpret newly measured spectra of unknown samples. Such learning can be accomplished by multivariate calibration in several ways, e.g. by Principal Component Regression (PCR), Partial Least Squares regression (PLS), Multiple Linear Regression (MLR), Artificial Neural Network (ANN), etc. A great advantage when using FTIR instruments is that such instruments may be standardised so that the same calibration can be applied to a plurality of standardised instruments.
FTIR instruments are costly. Accordingly, there is still a need for the less expensive filter instruments applying a few or at least a limited number of optical filters. It has so far been impossible to standardise such instruments, implying that every instrument must be calibrated separately, and when a measurement cell or any other change in the optical system has been carried out during maintenance, the instrument requires new calibrations.
In this context a calibration means the derivation of a mathematical expression, such as a functional relationship, enabling a prediction of a concentration of a specified constituent from a number of determined absorbance values.
The absorbance, a, is defined as the absorption relative to a reference. The absorbance is determined from signals Is, Io, measured by a detector, (e.g. as a measure in mV or mA), when measuring an unknown sample and a reference, respectively.a=log10(I0/Is)
When the absorbance values, a, have been determined for at least one, preferably a plurality of filters, e.g. four filters, the concentration c of a specific component may be predicted from an expression such as:c=b1*a1+b2*a2+b3*a3+b4*a4
The b-coefficients in the above equation may be determined by multivariate calibration after measuring a number of samples having various known concentrations of specific constituents. Calibrations are made for specific constituents, e.g. the fat content in milk.
The task of providing a good calibration for an instrument can be very laborious as it usually requires a great number of calibration samples having known concentration of a constituent in question. The calibration samples typically have to be analysed by tedious conventional methods and accordingly, a calibration sample is typically expensive. Since the calibration sample is typically a food product, e.g. a diary product, the durability is rather limited and new test samples have to be provided for each calibration.
Often, a calibrated instrument has to be re-calibrated from time to time. As an example, parts of the instrument, e.g. the cuvette or a detector may be replaced during repair or service. The new part may have a characteristic different from the characteristic of the previous part and accordingly, the relationship between the detected signal and the concentration of the constituent is different.

Method and a spectrometer for quantitative determination of a constituent in a sample


In an X-ray exposure method, consideration was made to application of a concept of a phase shift method which is used for a light exposure method, in order to improve the resolution. As a result, phase shift layers made of a material having an appropriate refractivity are provided on side walls of an absorbing pattern of an X-ray mask to improve the resolution by an interference effect. One or more layers made of a material having a refractivity different from that of the absorbing pattern are formed on the side walls of the absorbing pattern of the X-ray mask.

The present invention relates to a method of manufacturing a semiconductor device, and more particularly to an X-ray exposure method for transferring mask patterns onto a substrate by using a soft X-ray.
The X-ray exposure method is a semiconductor manufacturing process in which a mask consisting of an X-ray transmissible support film and absorbing patterns is irradiated with soft X-rays to transfer desired patterns onto a substrate by light transmitted through the mask. Since the soft X-ray has a wavelength two orders of magnitude shorter than an ultraviolet light which is used for a conventional light exposure method, it can reduce the influence of Fresnel diffraction and obtain a high resolution.
However, even with the X-ray exposure method, the influence of Fresnel diffraction causes deterioration in resolution in a sub-micron region. For this reason, for example, as discussed in "Micrelectronic Engineering", vol. 9, pp. 127-130, 1989 by Hasegawa et al, and JP-A-2-52416, trials have been made for improving the resolution by utilizing an interference effect of X-rays. These trials are featured by working side walls of an absorbing pattern 5 which has conventionally been rectangular as shown in FIG. 1a to a tapered shape 8 or the like as shown in FIG. 1b in order to change a optical path length of an X-ray. As a result, the phase of an X-ray 9 transmitted through the side walls of the absorbing pattern is advanced with respect to an X-ray 6 from an ordinary transmitting portion and interferes with expansion of an exposure intensity of the X-ray 6 due to Fresnel diffraction, whereby a distribution of exposure intensity by the transmitted X-rays is made abrupt, thereby making it possible to achieve the improvement of resolution.
In commonly assigned U.S. application Ser. No. 07/593808, filed Oct. 5, 1990, a technique is disclosed wherein, after forming a light shield film having a predetermined shape on a glass substrate, a flattening layer for flattening a difference in level of the light shield film, and a phase shifter is formed thereon.

X-ray exposure method with an X-ray mask comprising phase shifter sidewalls


A high temperture aqueous based zirconium (IV) crosslinked guar fracturing fluid having a pH from about 9 to about 12 includes a polymer solution and a zirconium (IV) crosslinking agent in an amount from about 0.1 PPTG to about 5 PPTG of the polymer solution. The polymer solution includes an aqueous fluid, natural guar gum in an amount from about 10 PPTG to about 100 PPTG of the aqueous fluid, a stabilizer in an amount from about 1 PPTG to about 50 PPTG of the aqueous fluid, a non-delayed alkaline buffer in an amount from about 1 PPTG to about 40 PPTG of the aqueous fluid, and a gelation delaying agent in an amount from about 0.25 PPTG to about 3.75 PPTG of the aqueous fluid, where those agents are combined to produce a fracturing fluid suitable to the purposes of hydraulically fracturing subterranean formations with static bottom-hole temperatures greater than 250xc2x0 F.

1. Field of the Invention
The present invention generally relates to fracturing fluids and, more particularly, but not by way of limitation, to an aqueous based zirconium (IV) crosslinked guar fracturing fluid and a method of making and use therefor, suitable to the purposes of hydraulically fracturing subterranean formations having static bottom-hole temperatures greater than about 250xc2x0 F.
2. Description of the Related Art
An aqueous based crosslinked polygalactomannan fluid is typically used to perform a hydraulic fracturing treatment of a hydrocarbon bearing reservoir when the static bottom-hole temperature of a well exceeds approximately 250xc2x0 F.
One type of aqueous based crosslinked polygalactomannan fluid that might be used in high temperature wells are borate crosslinked guar fluids, where the pH of the crosslinked fluid under treating conditions ranges from about 8.5 to about 12. Typical borate crosslinked guar fluids include, but are not limited to, those described in U.S. Pat. No. 5,145,590 (Dawson), U.S. Pat. No. 5,445,223 (Nelson et al), and in xe2x80x9cChemistry and Rheology of Borate-Crosslinked Fluids at Temperatures to 300xc2x0 F., P.C. Harris, J. Petroleum Technology, March 1993, pp. 264-269.
A second type of aqueous based crosslinked polygalactomannan fluid that might be used in fracturing high temperature wells are titanium (IV) or zirconium (IV) crosslinked derivatized guar fluids where the pH of the crosslinked fluid under treating conditions may range from about 3.5 to about 11. Typical derivatized guar polymers suitable to formulate a titanium (IV) or a zirconium (IV) crosslinked derivatized guar fluid include but are not limited to, alkyl-derivatives, such as hydroxypropyl guar (HPG), carboxyalkyl-derivatives, such as carboxymethyl guar (CMG), and carboxyalkyl-hydroxyalkyl-derivatives, such as carboxymethylhydroxypropyl guar (CMHPG). The guar used in the high temperature borate fracturing fluids is distinguishable from the derivatized guar used in the zirconium (IV) or titanium (IV) high temperature crosslinked fracturing fluid, in that guar for the borate crosslinked fluid is not subjected to a chemical treatment wherein some form of molecular substitution, such as alkylation, carboxylation or combinations thereof, has been performed to derivatize the guar. Typical titanium (IV) or zirconium (IV) crosslinked derivatized guar fluids include but are not limited to, those described in U.S. Pat. No. 3,888,312 (Tiner et al.), U.S. Pat. No. 4,534,870 (Williams), U.S. Pat. No. 4,686,052 (Baranet et al.), and U.S. Pat. No. 4,799,550 (Harris et al.)
In hydraulically fracturing a hydrocarbon bearing reservoir with an aqueous based crosslinked guar or derivatized guar fracturing fluid, it is often necessary that the aqueous based crosslinked guar or derivatized guar fracturing fluid exhibit more than an hour of stability. Those of ordinary skill in the art generally regard stability as a minimum viscosity achieved based upon an agreed rheological test method for an agreed period of time. The agreed rheological test method may be one proposed by the American Petroleum Institute (API) or an adaptation of an API method as proposed by a petroleum production company or its hydraulic fracturing service provider. Alternatively, the agreed rheological test method may be a novel method proposed and mutually agreed upon by the participants in the hydraulic fracturing fluid evaluation and may follow a regime based upon anticipated field conditions.
A borate crosslinked guar fracturing fluid is typically used when bottom-hole temperatures (BHT""s) of a well do not exceed about 325xc2x0 F. and where more than an hour of stability is necessary. A borate crosslinked guar fracturing fluid is generally made more stable by raising the pH of the fracturing fluid, increasing the borate concentration, or increasing the guar concentration in solution. A problem experienced in stabilizing the high temperature borate crosslinked fracturing fluid by raising the pH of the fluid, increasing the borate concentration, or increasing the guar concentration in solution is that pH, borate concentration, or guar concentration can be excessive, any of which may render the fracturing fluid unsuitable for use in the intended hydraulic fracturing treatment of a hydrocarbon bearing reservoir. Increasing chemical constituent loading to accommodate wells with higher BHT""s is also more costly.
A zirconium (IV) crosslinked derivatized guar fracturing fluid is typically used when the BHT of a well does not exceed about 400xc2x0 F. and where more than an hour of stability is necessary. A zirconium (IV) crosslinked derivatized guar fracturing fluid is generally made more stable by raising the pH of the fracturing fluid, increasing the zirconium (IV) concentration, or increasing the derivatized guar concentration in solution. A problem experienced in stabilizing the high temperature zirconium (IV) crosslinked fracturing fluid by raising the pH of the fluid, increasing the zirconium (IV) concentration, or increasing the derivatized guar concentration in solution is that pH, zirconium (IV) concentration, or derivatized guar concentration can be excessive, any of which may render the fracturing fluid unsuitable for use in the intended hydraulic fracturing treatment of a hydrocarbon bearing reservoir. Likewise, as is the case of borate crosslinked fluids, increasing chemical constituent loading to accommodate wells with higher BHT""s is also more costly.
A zirconium (IV) crosslinked derivatized guar fracturing fluid provides certain advantages over a borate crosslinked guar fracturing fluid, especially when BHT of a well exceeds about 325xc2x0 F. At BHT""s less than about 250xc2x0 F., a zirconium (IV) crosslinked derivatized guar fracturing fluid is usable at a pH of less than about 8.5, which is particularly advantageous if carbon dioxide comprises a portion of the fracturing fluid because the pH of the fracturing fluid may be as low as 3.5. Also, at BHT""s greater than about 250xc2x0 F., and certainly as BHT""s increase above about 325xc2x0 F., it is much easier and less costly to delay the gelation of a zirconium (IV) crosslinked derivatized guar fracturing fluid than a borate crosslinked guar fracturing fluid.
Although a zirconium (IV) crosslinked derivatized guar fracturing fluid provides certain operational advantages over a borate crosslinked guar fracturing fluid, a borate crosslinked guar fracturing fluid provides the advantage that it employs guar, which is less costly and more readily available than derivatized guar, and borate crosslinked guar fracturing fluids have historically been shown to operate to temperatures approximately 50xc2x0 F. higher than zirconium (IV) crosslinked guar fracturing fluids. Consequently, a zirconium (IV) crosslinked guar fracturing fluid is typically not suitable for hydraulic fracturing treatments where the BHT of a well exceeds about 275xc2x0 F. In those instances where a zirconium (IV) crosslinked guar fracturing fluid may be utilized where the BHT of a well exceeds 275xc2x0 F., the zirconium (IV) crosslinked guar fracturing fluid requires guar loadings in excess of 50 pounds of guar per 1000 gallons of make-up water and may often require as much as 80 pounds of guar per 1000 gallons of make-up water before a stable fracturing fluid is achieved. When such guar loadings are necessary, derivatized guar is utilized because, although it is more expensive, the derivatized guar requires considerably lower loading levels, and by virtue of the lower polymer loading, the spent fracturing fluid is easier to recover following the fracturing treatment.
Brannon et aL (U.S. Pat. No. 4,801,389) describe partially successful attempts to develop a zirconium (IV) crosslinked guar fracturing fluid for high temperature applications. Brannon et al. teaches to a fracturing fluid pH of about 8 to about 10. Any greater pH in this method tends to accelerate the crosslink rate thereby negating the benefit of delayed crosslinking on the subsequent rheological performance reported for the crosslinked fluid. Thus Brannon et al. were constrained to using sodium bicarbonate only as a buffering agent. This results in the disadvantage that the fluid has a lower pH than a fluid made with the corresponding carbonate. Additionally, the quantity of bicarbonate causes the onset of crosslinking to be substantially delayed whereas the presence of carbonate does not cause a substantial delay. This reduces the flexibility of the fluid since typically it is desirable to be able to vary the crosslink time of fracturing fluids. More flexibility in the control of crosslink time can be available with a blended buffer of bicarbonate and carbonate, where the overall bicarbonate loading can be varied. Furthermore, it is recognized that a greater pH, to pH 12 or higher, may substantially improve the rheological performance of this fluid. Because of the use of bicarbonate alone to control the crosslinking rate does not allow for the fluid pH to rise much above 9, fluids with bicarbonate buffering alone are not suitable for very high temperature wells. Additionally, Brannon et al. is apparently limited to a rheological performance (xe2x89xa7100 cP) of about 0.75 hrs at 325xc2x0 F., whereas most fracturing fluid treatments at this elevated temperature require  greater than 2 hrs performance at xe2x89xa7100 cP. Accordingly, there is a recognized and long felt need for a stable zirconium (IV) crosslinked fracturing fluid formulated utilizing guar at loadings at least comparable to the loadings of derivatized guar in a zirconium (IV) crosslinked derivatized guar fracturing fluid and utilizing a crosslinking delay agent that is not constrained by the pH of the buffer used.
In accordance with the present invention, an aqueous based zirconium (IV) crosslinked guar fracturing fluid having a pH from about 9 to about 12 includes a polymer solution and a zirconium (IV) crosslinking agent in an amount from about 0.1 gallons per thousand gallons(GPTG) to about 5 GPTG of the polymer solution. The polymer solution includes an aqueous fluid, natural guar gum in an amount from about 10 pounds per thousand gallons(PPTG) to about 100 PPTG of the aqueous fluid, a stabilizer in an amount from about 1 PPTG to about 50 PPTG of the aqueous fluid, a alkaline buffer in an amount from about 1 PPTG to about 40 PPTG of the aqueous fluid, and an alpha-hydroxycarboxylic acid delaying agent in an amount from about 0.25 PPTG to about 3.75 PPTG of the aqueous fluid. This crosslinker is typically applied as an aqueous or alcohol solution of the metal.
The aqueous fluid includes substantially any aqueous fluid that does not adversely react with one of the constituents of the fracturing fluid, the subterranean formation, and the fluids present therein. The aqueous fluid is selected from the group consisting of fresh water, natural brines, and artificial brines, such as potassium chloride solutions and sodium chlorides solutions.
The stabilizer includes any free-radical-scavenging compound and is selected from the group consisting of sodium thiosulfate, thiourea, urea, sodium sulfite, and methanol. The pH buffer includes one or more alkaline compounds selected from the group consisting of amines, or ammonium/amine, or alkali metal hydroxides, carbonates, and bicarbonates, such as ammonium hydroxide, potassium carbonate, and sodium bicarbonate, and thioethanolamine.
The delaying agent includes an alpha-hydroxycarboxylic acid selected from the group consisting of citric acid, malic acid, glycolic acid, lactic acid, tartaric acid, gluconic acid, glyceric acid, and mandelic acid. The delaying agent further includes an ammonium, amine, or alkali metal salt of an alpha-hydroxycarboxylic acid, such as sodium citrate and ammonium lactate.
The use of a combination of buffers together with the use of an alpha-hydroxycarboxylic acid or its salt, offers an advantage over Brannon et al., (U.S. Pat. No. 4,801,389) in that the crosslink delay time of the newly proposed fluid, is controllable over a wider pH range.
The zirconium (IV) crosslinking agent includes any zirconium compound or mixture of zirconium (IV) compounds, capable of solubilizing in an aqueous polymer solution to release the metal so that gelation takes place under controlled conditions. The zirconium (IV) crosslinking agent is selected from the group consisting of aqueous or alcohol solutions of complexes of alpha-hydroxycarboxylic acids, monoalkylamine zirconium compounds, dialkylamine zirconium compounds, trialkylamine zirconium compounds, and zirconium alkanolamine complexes. More precisely, the zirconium (IV) crosslinking agent may be selected from the group consisting of zirconium ammonium lactate, zirconium di or tri ethanolamine lactate, zirconium diisopropylamine lactate, zirconium sodium lactate salts, zirconium citrate, zirconium tartate, and zirconium glycolate, and like complexes, and mixtures thereof.
In a method for formulating an aqueous based zirconium (IV) crosslinked guar fracturing fluid having a pH from about 9 to about 12, an aqueous fluid is placed into a suitable mixing device. A stabilizer is added to the aqueous fluid in an amount from about 1 PPTG to about 50 PPTG of the aqueous fluid and allowed to dissolve into the aqueous fluid for a first predetermined period. Natural guar gum is added to the mixture in an amount from about 10 PPTG to about 100 PPTG of the aqueous fluid, and the mixture is mixed for a second predetermined period. An alkaline buffer is added to the mixture in an amount from about 1 PPTG to about 40 PPTG of the aqueous fluid, and the mixture is mixed for a third predetermined period. An alpha-hydroxycarboxylic acid delaying agent is added to the mixture in an amount from about 0.25 PPTG to about 3.75 PPTG of the aqueous fluid, and the mixture is mixed for a fourth predetermined period, thereby forming a polymer solution. A zirconium (IV) crosslinking agent is added in an amount from about 0.1 GPTG to about 5 GPTG of the formulated polymer solution, and mixing is performed until gelation occurs, thereby producing the fracturing fluid.
In a method of hydraulically fracturing a subterranean zone penetrated by a wellbore, an aqueous based zirconium (IV) crosslinked guar fracturing fluid having a pH from about 9 to about 12 is prepared. The fracturing fluid is pumped into the subterranean zone via the wellbore and permitted to gel after having substantially traversed the well bore or after having entered the subterranean formation, thereby causing hydraulic fracturing of the subterranean formation. Proppants may be added to the fracturing fluid, which is utilized to disperse the proppants throughout the subterranean formation. A breaker may be added to the fracturing fluid to permit the removal of the fracturing fluid from the subterranean formation.
It is therefore an object of the present invention to provide an aqueous based zirconium (IV) crosslinked guar fracturing fluid formulated utilizing guar at loadings at least comparable to the loadings of derivatized guar in a zirconium (IV) crosslinked derivatized guar fracturing fluid.
Still other objects, features, and advantages of the present invention will become evident to those of ordinary skill in the art in light of the following.

Aqueous based zirconium (IV) crosslinked guar fracturing fluid and a method of making and use therefor


With spreadsheet software, such as the MICROSOFT EXCEL, a radar chart can be compiled by the use of data in a table made.

(1) Field of the Invention
This invention relates to a program and method for displaying a radar chart and, more particularly, to a program and method for displaying a radar chart regarding a plurality of items.
(2) Description of the Related Art
Now various pieces of data including statistical data are processed by a computer to make graphs, such as radar charts, or tables. With a radar chart, statistical variables are assigned to the vertices of a polygon and an axis for each variable is set on a line segment which connects the center of the polygon and each vertex. A point indicative of the value of each variable is arranged on each axis and a broken line which passes each point is displayed. By using such a radar chart, the properties of an object of analysis can be shown plainly.
With spreadsheet software, such as the Microsoft Excel, a radar chart can be compiled by the use of data in a table made.
Radar charts which have been used are useful for indicating the statistical properties of an item, but it is difficult to use them for comparing the statistical properties of a plurality of items.
If there are a plurality of items, a broken line corresponding to each item can be displayed on one radar chart.
FIG. 19 is a view showing an example of a radar chart on which a plurality of broken lines are displayed. On a radar chart 300 shown in FIG. 19, broken lines 311 through 316 corresponding to the six items "Price," "Function," "Support," "Expandability," "Design," and "Portability" respectively are displayed. If the plurality of broken lines 311 through 316 are displayed on the radar chart 300 in this way, they will overlap one another, resulting in poor visibility.
Moreover, a plurality of radar charts corresponding to each item can also be displayed individually.
FIG. 20 is a view showing an example of a screen on which a plurality of radar charts are displayed. In FIG. 20, radar charts 321 through 326 corresponding to the six items "Price," "Function," "Support," "Expandability," "Design," and "Portability" respectively are displayed on a screen 320. If the plurality of radar charts 321 through 326 are displayed on the screen 320 in this way, the visibility of each broken line can be ensured. However, it is difficult to compare items in detail.

Program and method for displaying a radar chart


Methods and systems for generating and imaging THz electromagnetic radiation using a composite dipole array made up of novel structures of non-linear dipole strings with dual frequency resonances for frequency up conversion and frequency down conversion are disclosed. THz electromagnetic radiation resulting from the frequency down conversion process can be used as an illumination source for imaging, as a carrier for communications, or as an energy source for spectroscopy, for example. Optical electromagnetic radiation resulting from the frequency up conversion process can be used to form images from THz electromagnetic radiation for contraband detection, guidance systems, and medical applications, for example.

A Terahertz (THz) is a unit of frequency equal to 1012 hertz. THz electromagnetic radiation forms a large portion of the electromagnetic spectrum between the infrared and microwave regions. THz electromagnetic radiation is generally defined as covering frequencies from about 0.3 THz to about 30 THz. This corresponds to the range of wavelengths from about 1.0 mm to about 0.01 mm and is sometimes referred to as the sub-millimeter and/or far-infrared region of the electromagnetic spectrum. By way of comparison, visible light covers the frequency range of 428 THz to 750 THz, corresponding to wavelengths from 0.4 micron to 0.7 micron. Thus, THz electromagnetic radiation is in a previously much neglected range of frequencies between optical and radio waves.
THz electromagnetic radiation has interesting properties because its wavelengths are long enough to pass through some objects that are opaque to visible and IR light and are also short enough to be manipulated by conventional optical techniques. Thus, THz electromagnetic radiation can be used for the imaging of hidden objects. It is a particularly attractive means of detection because it can determine the composition, size, and shape of a variety of different substances.
The potential uses of THz electromagnetic radiation in various fields are presently being investigated. Specific applications include remote sensing, short range covert communications, compact radar ranging systems, inter-satellite communication links, testing of integrated circuits, and even medical imaging and treatment. In the field of medical imaging, for example, tumors and other pathologies may be identified and characterized. THz electromagnetic radiation may even find applications in a variety of other areas, including atmospheric sensing and upper atmospheric imagery.
Research into the potential use of THz electromagnetic radiation for the detection and characterization of contraband, such as chemicals (including illegal drugs, explosives, and toxic substances), biological agents (including aerosols) and concealed weapons, is being stimulated by law enforcement and homeland security concerns. By using THz electromagnetic radiation, drugs, explosives, and pathogens can be identified in parcels before they are opened. Concealed guns and knives can be observed on people. Even mines in minefields can potentially be located.
Further, the use of ambient THz electromagnetic radiation facilitates standoff detection of weapons and explosives. Standoff detection is particularly useful in determining whether a threat exists prior to the item or person posing the threat actually entering a sensitive area. That is, the threat can be identified before there is an opportunity to do the intended harm. For example, a THz electromagnetic radiation imaging system can be employed at the gate to a military base. If a threat is perceived, then the person posing the potential threat can be denied entry.
THz time-domain spectroscopy and related THz technologies promise to be of great benefit for military and civilian uses, because they offer innovative imaging and sensing technologies that can provide information not available through such conventional methods as microwave and x-ray. Spectral fingerprints can facilitate the identification of suspicious items.
The resolution of such spectra can be impressive. Not only can the type of explosive, drug, or pathogen be determined, but many times the factory where the substance was manufactured can be identified, as well. Thus, the potential forensic benefits are clear.
Compared to the relatively well-understood science and technology at microwave and optical frequencies, THz science and technology is in its infancy. This is largely due to the inadequate power of available contemporary THz sources and the limited resolution of contemporary THz imaging receivers.
The use of THz electromagnetic radiation in such applications is particularly attractive because, in many instance, it can be used passively. That is, THz electromagnetic radiation can be viewed without actively illuminating the subject. Other forms of imaging, such as those using x-ray and gamma ray backscatter, require that the subject be illuminated so as to provide the necessary radiation. Such illumination tends to pose some degree of health risks to human subjects and imaging equipment operators. However, in many instances sufficient THz electromagnetic radiation is generally present in the ambient environment to facilitate imaging. Thus, illumination is not always necessary for THz imaging. The elimination of a source of radiation by using ambient radiation both reduces costs and eliminates health concerns. It is also useful in covert applications.
In industrial applications, such as manufacturing and quality control, the use of an active source may be less objectionable. In such settings, provision for shielding can more readily be made. Further, in industrial settings the cost and space required for a source tend to be less problematic. Imaging can potentially be accomplished in either a transmission mode or a reflection mode of operation. In the transmission mode, the radiation source is on the opposite side of the subject with respect to the detection device and the radiation is transmitted through the subject to detect substances therein. In the reflection mode, the radiation source is on the same side of the subject with respect to the detection device and the radiation is reflected by substances within the subject.
Sensors for detecting THz electromagnetic radiation are presently being developed. Although prices are expect to decrease as development proceeds and as the sensors are produced in volume, the cost of contemporary sensors is high.
Another problem associated with the use of THz electromagnetic radiation is that contemporary THz electromagnetic radiation sources with suitable output power levels are undesirably large, heavy, and costly. The only way to generate THz electromagnetic radiation with average power over a watt, according to contemporary practice, is to use an accelerator, such as a 15 MeV synchrotron. As those skilled in the art will appreciate, such THz electromagnetic radiation sources are very large and very expensive. Even in industrial environments, it is generally desirable to reduce the size and cost of equipment.
In view of the foregoing, it is desirable to provide a source of THz electromagnetic radiation with output power levels of a few hundred milliwatts and higher that is smaller in size and less costly than contemporary sources. It is also desirable to provide a way to more readily facilitate the imaging in the THz frequency range of the electromagnetic spectrum.

Composite dipole array systems and methods


A method of detecting streaks in printed documents comprises, with an imaging device, capturing an image of a printed document, transmitting the image data representing the printed document to a computing device, with the computing device, dividing the image data into a number of rectangles horizontally across the image data so that the rectangles overlap in the horizontal direction, and with the computing device, determining if a rectangle comprises a streak. A system for detecting and evaluating streaks in printed document comprises a printing device that prints a document based on image data received from a computing device, an imaging device that captures an image of the printed document, and a streak detector that detects streaks within the captured image of the printed document.

With the advancement of printing processes and systems, quality control of a finished printed document is performed. A printed document sometimes includes various types of printing defects called streaks. Streaks may be the result of various mechanical disturbances within the printing device. For example, malfunctioning printing gear, contaminants such as, for example, a paper strip or other dirt adhered to a printer drum, or mechanical or physical obstructions such as debris in the printing device preventing proper function of the printer or displacement of parts of the printer that cause the printer to work improperly. The resulting streaks may occur globally on the entire printed page, and comprise a continuous or semi-continuous disturbance through the length of the printed document.
These streaks, whose widths may range from a few pixels up to a few mm, devalue the quality of the printed document. In such a case, a print shop or other dealer in printed materials may potentially loose revenue due to the poor quality of the printed document.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.

Hewlett-Packard Development Company, L.P.


An electronic device and a power module are provided. The power module includes a power housing; a circuit board, connected to the power housing and arranged with a plurality of pads on a surface of the circuit board facing the power housing; an electronic component, arranged on the circuit board and comprising a plurality of pins; wherein the plurality of pins are soldered and connected to the plurality of pads; and a first sealant layer, arranged on the surface of the circuit board facing the power housing, and covering the plurality of pins and the plurality of pads.

With the widespread application of electronic devices, the number of electronic components arranged on a circuit board in a power module is increasing. Pins of the electronic components are usually soldered on the circuit board. As the use time of the electronic devices is prolonged, the electrical connection between the pins of the electronic component and pads on the circuit board is likely to fail, which may cause damage to the electronic devices.

Electronic device and power module thereof

HUIZHOU FLUENCE OPTOELECTRONIC TECHNOLOGY CO., LTD.