An apparatus includes a storage device and a host device. The storage device may be configured to encrypt and decrypt user data during write and read operations, respectively. The host device is communicatively coupled to the storage device. The host device may be configured to execute the write and read operations by concentrating a first number of virtual bands into a second number of real bands, wherein said second number is smaller than said first number.

Self encrypting drives (SEDs) usually employ hardware to encrypt and decrypt user data during write and read operations, respectively. Encryption and decryption are accomplished using a media encryption key (MEK). The MEK is normally a function of logical block address (LBA), where an entire LBA space is subdivided into several LBA ranges (referred to as "data bands" or simply "bands") with a unique MEK for each band. Because of hardware limitations, the number of bands that an SED can support without serious performance degradation is limited (16 would be a reasonably high number). Having more active bands than the number of LBA ranges supported by hardware will have a negative effect on performance due to constant key swapping. From a perspective of a host in a traditional implementation, user data to which the host has access control under a single authentication key (AK) needs to be contiguously stored in a single LBA range. The single LBA range or band limitation makes it difficult for certain types of applications (like Virtual Machines—VMs) to benefit fully from SED deployment, because VMs might need many (perhaps, thousands) of bands to enable more flexible and efficient usage of the storage device.
It would be desirable to have virtual bands concentration for self encrypting drives.

Virtual bands concentration for self encrypting drives


An optical pickup apparatus comprises two light sources having two wavelengths (xcex1 less than xcex2) and a converging optical system having an objective lens. The objective lens comprises a central region; a peripheral region provided at an outside of the central region on at least one optical surface of the objective lens; a diffractive ring-shaped zones which is blazed on a basis of a wavelength xcex0 (xcex1 less than xcex0 less than xcex2) and is formed on each of the central region and the peripheral region; and a phase difference suppressing structure to suppress a phase difference between a wavefront of a light flux passing the central region and a wavefront of a light flux passing the peripheral region when recording or reproducing information is conducted for the first optical information recording medium.

The present invention relates, to an optical pick-up device and an objective lens used therein, for example, to an optical pick-up device which can perform information recording and/or information reproduction for two optical information recording media each having a different thickness of a transparent base board and an objective lens used therein.
With the practical use of a short wave red semiconductor laser in recent years, there has been developed a high density optical disk DVD (digital video disk) that is the same in size as a conventional optical disk CD (compact disk) representing an information recording medium, and has a larger capacity. In order to attain high density of a recording signal, it is requested to make a spot formed on a recording medium by an objective lens to be smaller in an optical system of an optical information recording/reproducing device employing such an optical disk. Therefore, there are the facts that a wavelength of a laser representing a light source is made to be shorter and a numerical aperture of an objective lens is made to be higher.
For example, in an optical pick-up device that performs information recording and/or reproduction for DVD, when a short wave semiconductor laser ray having a wavelength of about 650 nm is used as a light source, numerical aperture NA closer to the optical disk is approximately 0.6 for the objective lens that converges the laser ray. Incidentally, in CD and DVD, there are optical disks under various kinds of standards, including, for example, CD-R (write-once read-many compact disk), and in addition to CD and DVD, there is MD (mini disk) that has been commercialized and has become popular.
On the other hand, in the optical pick-up device that performs information recording and/or reproduction for CD-R, it is necessary to use the light source having a wavelength of about 780 nm. For the other optical disks, it is possible to use the light source having a wavelength other than the specific wavelength. In this case, a necessary numerical aperture NA can be changed in accordance with the wavelength xcex of the light source used therein. For example, the necessary numerical aperture is NA=xcex (xcexcm)/1.73 approximately for CD, while the necessary numerical aperture is NA=xcex (xcexcm)/1.06 approximately for DVD. The numerical aperture in the present specification means a numerical aperture of the converging optical system viewed from the optical disk side. The necessary numerical aperture means a numerical aperture that is calculated by both spot size d required on the recording surface of the optical disk and wavelength xcex in use, and that is commonly shown by the formula NA=0.83xc3x97xcex/d.
As mentioned above, in the market, there exist various kinds of the optical disks having different transparent base board thicknesses, different recording densities and different wavelengths in use. However it is too heavy a burden for the user to purchase the exclusive information recording and reproduction device which can perform information recording and/or reproduction for each optical disk. Therefore, there is proposed the information recording/reproduction device provided with the interchangeable optical pick-up device that can cope with the various optical disks.
In such an optical disk, when light fluxes each having a different wavelength are made to enter the base boards each having a different thickness, it is necessary to correct spherical aberration to be the prescribed value or less, and to control a spot diameter of each light flux to be within the prescribed range, in order to perform information writing and reading properly.
As a solution for the foregoing, there is proposed the optical pick-up device wherein converging optical systems are provided for different optical disks respectively, and optical converging systems are switched in accordance with the optical disks to be reproduced. The optical pick-up device mentioned above makes it possible to correct the spherical aberration to be under the prescribed value, and to make the spot diameter of each light flux to be within the prescribed range, when the light fluxes having different wavelengths are incident on the base boards having different thicknesses. However, this optical pick-up device requires a plurality of light converging optical systems, to cause the complicated structure and higher cost, which is not preferable.
For this problem, there is developed an objective lens having a diffractive structure that can converge the light flux passing within the prescribed numerical aperture to spot light and that can make the light flux passing beyond the prescribed numerical aperture to be flared light. This objective lens can obtain spot light having a necessary diameter for the information recording or reproduction for the various optical information recording media such as, for example, CD and DVD.
Here, in the objective lens having the diffractive structure stated above, wave front aberration caused by the difference of the wavelength of the light source is generated originally, because the light flux having the numerical aperture smaller than the prescribed numerical aperture is used for the information recording or reproduction for the various optical information recording media such as CD and DVD commonly. Accordingly, it is necessary to make the characteristic of the wave front aberration to be better by some means. Further, there is request to increase the spot light amount for the optical information recording media having thick base board such as CD.
The object of the present invention is to provide the optical pick-up device and the objective lens which can control a phase shift of a wave front, in the objective lens which is used for the information recording or reproduction for the various optical information recording media such as CD and DVD commonly.
The object of the present invention is to provide the optical pick-up device and the objective lens which have the better characteristic of the wave front aberration, in the objective lens which is used for the information recording or reproduction for the various optical information recording media such as CD and DVD commonly.
Further, the object of the present invention is to provide the optical pick-up device and the objective lens which can increase the spot light amount, for the optical information recording medium such as CD having the thick base board, in the objective lens which is used for the information recording or reproduction for the various optical information recording media such as CD and DVD commonly.
An optical pick-up device has a first light source having wavelength xcex1, a second light source having wavelength xcex2 (xcex1 less than xcex2) and a converging optical system including an objective lens which converges the light fluxes emitted from the first light source and the second light source onto an information recording surface of the optical information recording medium, and being capable of performing the information recording and/or reproduction for the first optical information recording medium whose transparent base board thickness is t1, by using the first light source and the converging optical system, and being capable of performing the information recording and/or reproduction for tile second optical information recording medium whose transparent base board thickness is t2 (t1 less than t2), by using the second light source and the converging optical system, wherein when NA1 is a first necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the first optical information recording medium, using the first light source and tile converging optical system, and when NA2 (NA1 less than NA2) is a second necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the second optical information recording medium, using the second light source and at the converging optical system, at least one optical surface of the objective lens is provided with a central area which is from an optical axis to a prescribed distance corresponding to the second necessary numerical aperture NA2, and with a peripheral area which is outside the prescribed distance, and on the central area and the peripheral area, there are formed the diffractive structures having the diffractive ring-shaped zones blazed concerning the wavelength xcex0 (xcex1 less than xcex0 less than xcex2), and wherein when the information recording and/or reproduction is performed for the first optical information recording medium, controlled is the phase shift (phase difference) between the wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area. The present invention is explained as follows.
FIG. 1(a) is a schematic section in the optical axial direction of the objective lens, shown as a comparative example. FIG. 1(b) is a drawing showing illustratively the wave front aberration of the objective lens representing the comparative example, in the case of performing the information recording and/or reproduction for the first optical information recording medium. Since the phase shift equivalent to integer multiples of 2xcfx80 in the wave front aberration does not affect an image formation, the phase shift is excluded from the wave front aberration. The second necessary numerical aperture NA2 is 0.47 in this case. In the objective lens shown as the comparative example, since the peripheral area whose second necessary numerical aperture NA2 is equal to or greater than 0.47 is an exclusive area where the light flux performing the information recording and/or reproduction for the first optical information recording medium passes through, the blazing wavelength can be equal to the light wavelength in a practical use, accordingly, it is possible to keep the wave front aberration to be constant, in principle. However, in the central area whose necessary numerical aperture NA2 is equal to or less than 0.47, in order to obtain the adequate diffractive efficiency for both of the first and second optical information recording media, it is necessary to make the blazing wavelength for forming the diffractive ring-shaped zone to be different from the light wavelength in a practical use, and therefore, when the information recording and/or reproduction is performed for the first optical information recording medium, the phase shift of about 0.05 xcex1 is caused between the wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area.
In order to dissolve the phase shift, the central area and the peripheral area form the diffractive structures having blazed diffractive ring-shaped zones concerning the wave length xcex0 (xcexa less than xcex0 less than xcex2), in an objective lens of an optical pick-up device. Here, to blaze concerning the wavelength xcex0 means to design the diffractive ring-shaped zone so that diffractive efficiency may be raised to the highest level at the wavelength xcex0.
FIG. 2(a) is a schematic section in the optical axial direction of the objective lens of the optical pick-up device of the present invention. FIG. 2(b) is a drawing showing illustratively the wave front aberration of the objective lens of the optical pick-up device of the invention, in the case of performing the information recording and/or reproduction for the first optical information recording medium.
As understood from FIG. 2(b), it is possible to make the average value of the wave front aberration in the peripheral area to be equal to the average value of the wave front aberration in the central area practically, by forming the diffractive structures having the diffractive ring-shaped zones blazed concerning the wavelength xcex0 on both of the central area and the peripheral area, though the wave front aberration according to the shape of the ring-shaped zone is caused on the peripheral area. By setting the average values of the wave front aberrations to be equal each other mentioned above, the phase shift becomes 0 approximately or less than 0.05 xcex1, which can improve the wave front aberration.
In an optical pick-up device, there is a step generated in the optical axial direction, between an imaginary enveloping surface which is formed by jointing the crests in the direction of the optical axis of the diffractive ring-shaped zone of the central area and an imaginary enveloping surface which is formed by jointing the crests in the direction of the optical axis of the diffractive ring-shaped zone of the peripheral area, and the step is not less than 1 xcexcm and not grater than 10 xcexcm, therefore, when the information recording and/or reproduction is performed for the first optical information recording medium, for example, by providing the step which makes the light path difference to be equivalent to the integer multiples of the wave length xcex1, the characteristic of the change of the aberration for temperature changes can be improved without affecting the phase shift.
In an optical pick-up device, when the information recording and/or reproduction is performed for the first optical recording medium, it is preferable if the phase shift between the wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area is 0.05 xcex1 or less.
An optical pick-up device has a first light source having wavelength xcex1, a second light source having wavelength xcex2 (xcex1 less than xcex2) and a converging optical system including an objective lens which converges the light fluxes emitted from the first light source and the second light source onto an information recording surface of the optical information recording medium, and being capable of performing the information recording and/or reproduction for the first optical information recording medium whose transparent base board thickness is t1, by using the first light source and the converging optical system, and being capable of performing the information recording and/or reproduction for the second optical information recording medium whose transparent base board thickness if t2 (t1 less than t2), by using the second light source and the converging optical system, wherein when NA1 is a first necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the first optical information recording medium, using the first light source and the converging optical system, and when NA2 (NA1 less than NA2) is a second necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the second optical information recording medium, using the second light source and the converging optical system, at least one optical surface of the objective lens is provided with a central area which is from an optical axis to a prescribed distance corresponding to the second necessary numerical aperture NA2, and is provided with a peripheral area which is outside the prescribed distance, and on the central area, there is formed the central diffractive structure having the diffractive ring-shaped zone blazed concerning the light flux having the wavelength xcex0 (xcex1 less than xcex0 less than xcex2), and on the peripheral area, there is formed the peripheral diffractive structure having the diffractive ring-shaped zone blazed concerning the light flux having wavelength xcex0xe2x80x2 (xcex0xe2x80x2 less than xcex0), wherein the imaginary enveloping surface which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the central area is discontinuous with the imaginary enveloping surface which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the peripheral area, and wherein controlled is the phase shift between the wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area. The present invention is explained as follows.
FIG. 3(a) is a schematic section in the optical axial direction of the objective lens of the optical pick-up device of the invention. FIG. 3(b) is a drawing showing illustratively the wave front aberration of the objective lens of the optical pick-up device of the invention, in the case of performing the information recording and/or reproduction for the first optical information recording medium.
For the peripheral area whose second necessary numerical aperture NA2 is not less than 0.47, it is possible to keep the wave front aberration constant, by equalizing the blazing wavelength with the wavelength in use as shown in the upper part of FIG. 3(b). Further, for the central area whose second necessary numerical aperture NA2 is not greater than 0.47, it is possible to make the characteristic of the wave front aberration better, by bringing the average wave front closer to the average wave front in the peripheral area, (see the lower part in FIG. 3(b)), by making imaginary enveloping surface P1 which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the central area to be discontinuous with imaginary enveloping surface P2 which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the peripheral area.
In an optical pick-up device, there is a step generated in the optical axial direction, between an imaginary enveloping surface which is formed by jointing the crests in the direction of the optical axis of the diffractive ring-shaped zone of the central diffractive structure and an imaginary enveloping surface which is formed by jointing the crests in the direction of the optical axis of the diffractive ring-shaped zone of the peripheral diffractive structure, and the step is not less than 1 xcexcm and not greater than 10 xcexcm, therefore, when the information recording and/or reproduction is performed for the first optical information recording medium, for example, by providing the step which makes the light path difference to be equivalent to integer multiples of the wave length xcex1, the characteristic of the change of the aberration for temperature changes can be improved without affecting the phase shift.
In an optical pick-up device, when the information recording and/or reproduction is performed for the first optical recording medium, it is preferable if the phase shift between tile wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area is 0.05 xcex1 or less.
An optical pick-up device has a first light source having wavelength xcex1, a second light source having wavelength xcex2 (xcex1 less than xcex2) and a converging optical system including an objective lens which converges the light fluxes emitted from the first light source and the second light source onto an information recording surface of the optical information recording medium, and being capable of performing the information recording and/or reproduction for the first optical information recording medium whose transparent base board thickness is t1, by using the first light source and the converging optical system, and being capable of performing the information recording and/or reproduction for the second optical information recording medium whose transparent base board thickness is t2 (t1 less than t2), by using the second light source and the converging optical system, wherein when NA1 is a first necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the first optical information recording medium, using the first light source and the converging optical system, and when NA2 (NA1 less than NA2) is a second necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the second optical information recording medium, using the second light source and the converging optical system, at least one optical surface of the objective lens is provided with a central area which is from an optical axis to a prescribed distance corresponding to the second necessary numerical aperture NA2, and is provided with a peripheral area which is outside the prescribed distance, and on the central area, there is formed the central diffractive structure having the diffractive ring-shaped zone blazed concerning the light flux having the wavelength xcex0 (xcex1 less than xcex0 less than xcex2), and wherein lightened is at least either one of the wave front aberration generated by the difference between the light source wavelength xcex1 and the blazing wavelength xcex0, when the information recording and/or reproduction is performed for the first optical information recording medium, and the wave front aberration generated by the difference between the light source wavelength xcex2 and the blazing wavelength xcex0, when the information recording and/or reproduction is performed for the second optical information recording medium. The invention will be explained as follows.
The invention is attained in order to improve the minute wave front aberration, that is generated by the difference of the blazing wavelength and the wavelength in use in each of the diffractive ring-shaped zone. If there is the wave front aberration of low order power of the aperture in the objective lens for the optical pick-up, it is generally said that the characteristics of a jitter signal and others become worse. Accordingly, when the wave front aberration generated by the difference between the blazing wavelength and the wavelength in use is expressed by the power series of NA, it is desirable to design the third-order spherical aberration and the fifth-order spherical aberration which have been corrected beforehand. A designing technique which controls the third-order or higher order spherical aberrations concretely is the incorporation of the low-order wave front aberration in advance, which is generated by the difference between the blazing wavelength and the wavelength in use, into the design, when the pitch of the ring-shaped zone and the macroscopic aspheric surface are designed. Especially, the diffractive ring-shaped zone of the central diffractive structure including the optical axis has a large area, where the low-order spherical aberration is easily generated, which must be considered as the important matter.
An optical pick-up device has a first light source having wavelength xcex1, a second light source having wavelength xcex2 (xcex1 less than xcex2) and a converging optical system including an objective lens which converges the light fluxes emitted form the first light source and the second light source onto an information recording surface of the optical information recording medium, and being capable of performing the information recording and/or reproduction for the first optical information recording medium whose transparent base board thickness is t1, by using the first light source and the converging optical system, and being capable of performing the information recording and/or reproduction for the second optical information recording medium whose transparent base board thickness is t2 (t1 less than t2), by using the second light source and the converging optical system, wherein the NA1 is a first necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the first optical information recording medium, using the first light source and the converging optical system, and when NA2 (NA1 less than NA2) is a second necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the second optical information recording medium, using the second light source and the converging optical system, at least one optical surface of the objective lens is provided with a central area which is from an optical axis to a prescribed distance corresponding to the second necessary numerical aperture NA2, and is provided with a peripheral area which is outside the prescribed distance, and on the central area and the peripheral area, there are formed the diffractive structures provided with the diffractive ring-shaped zones, and wherein the diffractive structure of the central area and at least the diffractive structure of the peripheral area contacting the central area are blazed concerning the wavelength xcex0 (xcex1 less than xcex0 less than xcex2). The invention will be explained as follows.
When the recording and/or reproduction is performed at high speed for the second optical information recording medium such as CD, it is necessary to converge a large amount of light by the objective lens. However, the increase of the numerical aperture NA (NA2 in this case) of the area (the central area in this case) where the aberration is to be corrected causes the too small beam and the bad influence such as the deterioration of the tolerance. Accordingly it is required to increase spot light amount, without increasing the numerical aperture NA of the area where the aberration is to be corrected. As a result of the investigation by the inventers for the present invention, it is understood that the area (the peripheral area in this case) which is not used for the information recording and/or reproduction for the second optical information recording medium, such as the area where the aberration is not corrected and the flare is generated, can contribute to the light amount of the spot for the information recording and/or reproduction for the second optical information recording medium. Based on the result of the investigation, by blazing the diffractive structure in the central area and at least the diffractive structure of the peripheral area contacting the central area, concerning the light flux having wavelength xcex0, the invention can obtain the large light amount of the spot, to perform the information recording and/or reproduction for the second optical information recording medium.
Here, by equalizing the blazing wavelength xcex0 of the peripheral area to the wavelength xcex1 used for the first optical information recording medium, it is possible to obtain the higher diffractive efficiency of the diffractive structure in the peripheral area for the first optical information recording medium, however, the diffractive efficiency becomes lower for the wavelength xcex2 used for the second optical information recording medium. Therefore, the blazing wavelength of the diffractive structure in the area (near the border to the central area in the peripheral area, that is, the area contacting the central area) whose numerical aperture NA is relatively small, for example, NA is 0.47 to 0.52 in the peripheral area, is equalized to the blazing wavelength of the diffractive structure in the central area, then, the diffractive efficiency concerning the light flux having wavelength xcex2 becomes large for this area, and it is possible to obtain large amount of light flux for the information recording and/or reproduction for the second optical information recording medium.
An objective lens of an optical pick-up device has a first light source having wavelength xcex1, a second light source having wavelength xcex2 (xcex1 less than xcex2) and a converging optical system including an objective lens which converges the light fluxes emitted from the first light source and the second light source onto an information recording surface of the optical information recording medium, and being capable of performing the information recording and/or reproduction for the first optical information recording medium whose transparent base board thickness is t1, by using the first light source and the converging optical system, and being capable of performing the information recording and/or reproduction for the second optical information recording medium whose transparent base board thickness is t2 (t1 less than t2), by using the second light source and the converging optical system, wherein when NA1 is a first necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the first optical information recording medium, using the first light source and the converging optical system, and when NA2 (NA1 less than NA2) is a second necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the second optical information recording medium, using the second light source and the converging optical system, at least one optical surface of the objective lens is provided with a central area which is from an optical axis to a prescribed distance corresponding to the second necessary numerical aperture NA2, and is provided with a peripheral area which is outside the prescribed distance, and on the central area and the peripheral area, there are formed the diffractive structures having the diffractive ring-shaped zones blazed concerning the wavelength xcex0 (xcex1 less than xcex0 less than xcex2), and wherein when the information recording and/or reproduction is performed for the first optical information recording medium, controlled is the phase shift between the wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area.
In an objective lens of an optical pick-up device, there is a step generated in the optical axial direction, between an imaginary enveloping surface which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the central area and an imaginary enveloping surface which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the peripheral area, and the step is not less than 1 xcexcm and not greater than 10 xcexcm.
In an objective lens of an optical pick-up device, when the information recording and/or reproduction is performed for the first optical recording medium, the phase shift between the wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area is 0.05 xcex1 or less.
An objective lens of an optical pick-up device has a first light source having wavelength xcex1, a second light source having wavelength xcex2 (xcex1 less than xcex2) and a converging optical system including an objective lens which converges the light fluxes emitted from the first light source and the second light source onto an information recording surface of the optical information recording medium, and being capable of performing the information recording and/or reproduction for the first optical information recording medium whose transparent base board thickness is t1, by using the first light source and the converging optical system, and being capable of performing the information recording and/or reproduction for the second optical information recording medium whose transparent base board thickness is t2 (t1 less than t2), by using the second light source and the converging optical system, wherein when NA1 is a first necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the first optical information recording medium, using the first light source and the converging optical system, and when NA2 (NA1 less than NA2) is a second necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the second optical information recording medium, using the second light source and the converging optical system, at least one optical surface of the objective lens is provided with a central area which is from an optical axis to a prescribed distance corresponding to the second necessary numerical aperture NA2, and is provided with a peripheral area which is outside the prescribed distance, and on the central area, there is formed the central diffractive structure having the diffractive ring-shaped zone blazed concerning the light flux having the wavelength xcex0 (xcex1 less than xcex0 less than xcex2), and on the peripheral area, there is formed the peripheral diffractive structure having the diffractive ring-shaped zone blazed concerning the light flux having wavelength xcex0xe2x80x2 (xcex0xe2x80x2 less than xcex0), wherein the imaginary enveloping surface which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the central area is discontinuous with the imaginary enveloping surface which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the peripheral area, and where in controlled is the phase shift between the wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area.
In an objective lens of an optical pick-up device, there is a step generated in the optical axial direction, between an imaginary enveloping surface which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the central diffractive structure and an imaginary enveloping surface which is formed by jointing the crests directed to the optical axis of the diffractive ring-shaped zone of the peripheral diffractive structure, and the step is not less than 1 xcexcm and not greater than 10 xcexcm.
In an objective lens of an optical pick-up device, when the information recording and/or reproduction is performed for the first optical recording medium, the phase shift between the wave front of the light flux passing through the central area and the wave front of the light flux passing through the peripheral area is 0.05 xcex1 or less.
An objective lens of an optical pick-up device has a first light source having wavelength xcex1, a second light source having wavelength xcex2 (xcex1 xcex2) and a converging optical system including an objective lens which converges the light fluxes emitted from the first light source and the second light source onto an information recording surface of the optical information recording medium, and being capable of performing the information recording and/or reproduction for the first optical information recording medium whose transparent base board thickness is t1, by using the first light source and the converging optical system, and being capable of performing the information recording and/or reproduction for the second optical information recording medium whose transparent base board thickness is t2 (t1 less than t2), by using the second light source and the converging optical system, wherein when NA1 is a first necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the first optical information recording medium, using the first light source and the converging optical system, and when NA2 (NA1 less than NA2) is a second necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the second optical information recording medium, using the second light source and the converging optical system, at least one optical surface of the objective lens is provided with a central area which is from an optical axis to a prescribed distance corresponding to the second necessary numerical aperture NA2, and is provided with a peripheral area which is outside the prescribed distance, and on the central area, there is formed the central diffractive structure having the diffractive ring-shaped zone blazed concerning the light flux having the wavelength xcex0 (xcex1 less than xcex0 less than xcex2), and wherein lightened is at least either one of the wave front aberration generated by the difference between the light source wavelength xcex1 and the blazing wavelength xcex0, when the information recording and/or reproduction is performed for the first optical information recording medium, and the wave front aberration generated by the difference between the light source wavelength xcex2 and the blazing wavelength xcex0, when the information recording and/or reproduction is performed for the second optical information recording medium.
An objective lens of an optical pick-up device has a first light source having wavelength xcex1, a second light source having wavelength xcex2 (xcex1 less than xcex2) and a converging optical system including an objective lens which converges the light fluxes emitted from the First light source and the second light source onto an information recording surface of the optical information recording medium, and being capable of performing the information recording and/or reproduction for the first optical information recording medium whose transparent base board thickness is t1, by using the first light source and the converging optical system, and being capable of performing the information recording and/or reproduction for the second optical information recording medium whose transparent base board thickness is t2 (t1 less than t2), by using the second light source and the converging optical system, wherein when NA1 is a first necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the first optical information recording medium, using the first light source and the converging optical system, and when NA2 (NA1 less than NA2) is a second necessary numerical aperture of the objective lens which performs the information recording and/or reproduction for the second optical information recording medium, using the second light source and the converging optical system, at least one optical surface of the objective lens is provided with a central area which is from an optical axis to a prescribed distance corresponding to the second necessary numerical aperture NA2, and is provided with a peripheral area which is outside the prescribed distance, and on the central area and the peripheral area, there are formed the diffractive structures provided with the diffractive ring-shaped zones, and wherein the diffractive structure of the central area and the diffractive structure positioned at least contacting with the central area are blazed concerning the wavelength xcex0 (xcex1 less than xcex0 less than xcex2).
The xe2x80x9cdiffractive structurexe2x80x9d used in the present specification means the section which is provided with relief on the surface of the objective lens and has the function to converge or diverge the light flux by diffraction. Concerning the form of relief, as shown in FIG. 2(a), for example, there is known the shape wherein ring-shaped zones are formed to be the concentric circles around the optical axis representing the center, and when its section on a plane including an optical axis is viewed, each ring-shaped zone is like the saw-tooth. The form of relief includes above-mentioned shape, and this shape is named xe2x80x9cthe diffractive ring-shaped zonexe2x80x9d especially.
In the present specification, in a narrow sense, the objective lens means the lens having light converging function and being arranged to face the optical information recording medium at the closest position to the optical information recording medium, under the condition that the optical information recording medium is installed on the optical pick-up device. In a wide sense, the objective lens means the lens group which can be moved by an actuator together with the lens at least in the direction of the optical axis of the lens. Here, such lens group means at least one or more lens pieces (for example, two pieces). Accordingly, in the present specification, the numerical aperture NA of the objective lens on the optical information recording medium side (an image side) means the numerical aperture NA of the objective lens through which the light flux pass the lens surface positioned to be closest to the optical information recording medium. Further, in the present specification, the necessary numerical aperture NA means the numerical aperture which is regulated by the standard of each optical information recording medium, or means the numerical aperture of the objective lens having the diffractive limit power which can obtain the spot diameter necessary to perform recording or reproduction of information for each of the optical information recording media, in accordance with the wavelength of the light source to be used.
In the present specification, the second optical information recording medium means the optical disks of various CD groups representing, for example, CD-R, CD-RW, CD-Video and CD-ROM, while the first optical information recording medium means the optical disks of various DVD groups representing DVD-ROM, DVD-RAM, DVD-R, DVD-RW and DVD-Video. Still further, in the present specification, when the thickness t of the transparent base board is mentioned, it includes the case of t=0.
In this specification, the information recording and/or reproduction means to record information on the information recording surface of the optical information recording medium as mentioned above, and/or to reproduce information recorded on the information recording surface. The optical pick-up device of the invention can be used for either the recording only or the reproduction only, or for both of the recording and the reproduction. Further, the optical pick-up device of the invention can be used for either the recording for one information recording medium and the reproduction for the other information recording medium, or for the recording or the reproduction for one information recording medium and for the recording and reproduction for the other information recording medium. Incidentally, the reproduction in this case includes only reading of information.

Optical pick-up device and objective lens used therein


A micro coaxial cable connector assembly for contact with a mating electrical connector, includes a first and second housing means, a cable set with a plurality of cables, and a plurality of contacts. The first and second housing members are efficiently and durably retained together by means of the cooperation between a pair of channels and latch portions thereof and the interference fit of first retention sections and second retention sections of the contacts with a plurality of grooves and the passageways thereof. The cable set consists of the juxtaposed cables each having at least a signal segment and a grounding segment, and a grounding bar defined with two plates soldered with the grounding segments of the cables. Each passageway is equipped with multi-directional orientating means for convenience of soldering the signal segment of the cable with the tail section of the corresponding contact via an external tool. A method of making the cable connector assembly is introduced for convenience of the assembly.

1. Field of the Invention
The present invention relates to a micro connector assembly for link with a remote micro coaxial cable, and particularity to a micro connector assembly for electrical and mechanical contact with an external mating connector.
2. The Prior Art
In a conventional micro connector as introduced in U.S. Pat. No. 5,871,369 and Japanese Patent Publication No. 09-055243, a plurality of conductive cores 21 through 26 of a flat cable 17 are respectively fitted into several notches 31 through 36 defined inside a main body 10 of the connector 1. An elongated contact bar 18 composed of an insulating material is then placed inside a groove 28 of the main body 10 defined perpendicular to a longitudinal axis of each notch 31 thereby locating above the conductive cores 21 through 26 in perpendicular relationship. Eventually, an insulative cover 19 is restrainedly attached above the main body 10 to press down the conductive cores 21 through 26 via the contact bar 18. Thus, the conductive cores 21 through 26 each relatively deflects down a spring contact arm 14a of one of the contacts 14 in a main body 10 of the connector 1 thereby establishing electrical connection between the cable 17 and the contacts 14.
However, such a said connector has poor mechanical connection with the cable because of the absence of an efficient horizontal retention means to prevent the separation of the cable from connector or the conductive cores of the cable from cable after action of an excessive withdrawing force thereon. Furthermore, during the process of the moveable installation of the cover 19 within the main body 10, a permanent deformation may happen in either of the spring contact arms 14a due to improper operation. The minimized dimension and flexibility of the conductive cores will increase difficulty and inconvenience of the assembly with the corresponding notches 31 of the main body 10 or the poor engagement with the contact arm 14a under the absence of an orientation means thereon.
Another conventional design on the micro type connector like Japanese Patent Publication Nos. 10-321314 and 10-255921 introduces that a cable holder of the connector defines a row of U-shaped grooves at a front end for reception of the corresponding conductive cores of the coaxial cable therein. When the grooves of the cable holder are respectively fitted and inserted between a tuning fork type tips of the corresponding contact, the upper and lower side tips of the contacts are brought to press down the conductive cores on one side/reversed sides of the U-shaped grooves. However, the fork type tips of the contact or the conductive cores are easily damaged or permanently deformed due to tight fit therebetween resulting from restriction of a housing where the contacts are received. The tight fit is still insufficient to firmly retain the cable holder with the housing, especially in exercise of an excessive full force on the cable.
The instant application is a continuation-in-part of U.S. patent application No. 09/350,942 filed on Jul. 09, 1999 which discloses a first and second housing members, a cable set with a plurality of cables, and a plurality of contacts. The second housing member defines a plurality of passageways each with a pair of protrusions on opposite lateral sides thereof. Thus, a signal segment of each of the cables is precisely positioned above a tail section of the corresponding contact within the corresponding passageway by way of orientating of the protrusions. Then, the signal segment of the cable is soldered with the tail section of the corresponding contact together.
Although the protrusions expedite the orientation of the signal segment of the cable within the corresponding passageway. It is hard to inspect whether the signal segment of the cable and the tail section of the corresponding contact in each passageway are efficiently engaged with each other before being soldered together.

Micro connector assembly and method of making the same


A pattern selection apparatus displays patterns and allows any of the displayed patterns to be directly selected. The apparatus comprises a control circuit, a display unit, an item designating dial and a selection establishing key. The control circuit indicates on the display unit where a cursor-highlighted displayed pattern is located relative to all the patterns under the same subset heading. As the cursor is moved in response to rotation of the item designating dial, the pattern location indication is correspondingly changed. Pushing the selection establishing key selects the cursor-highlighted pattern. Thus, any of the patterns displayed on the display unit is selected quickly and easily.

1. Field of the Invention
This invention relates to a pattern selection apparatus capable of displaying patterns on a display unit and allowing any of the displayed patterns to be directly selected.
2. Description of the Related Art
A conventional pattern selection apparatus comprises a recording medium such as a ROM and a display unit equipped with a touch panel. The recording medium contains predetermined data for a plurality of patterns. The display unit displays patterns based on the pattern data and allows any one pattern to be selected with the touch panel. When an operator touches an appropriate position on the display unit screen, the displayed pattern corresponding to the touched position is selected. The recording medium contains data about numerous patterns. In most cases, it is impossible to display all of the patterns on the screen at once. Instead, the patterns are displayed one after another when the operator scrolls the screen. When a desired pattern is reached, the operator selects that pattern.
Another type of conventional pattern selection apparatus comprises numeric keys that allow the operator to select the number corresponding to each of the individual prestored patterns.
With the former type of pattern selection apparatus, which allows the operator to select a pattern from among various patterns as they are scrolled, it is difficult for the operator to know where the currently displayed pattern is located, relative to the other patterns stored in the ROM. That is, the operator finds it difficult to know which way to scroll the screen to reach the desired pattern most efficiently and quickly. Thus, the time needed for the operator to search for and determine the next pattern to be selected is needlessly increased.
With the latter type of pattern selection apparatus, which allows the operator to directly select a pattern number with numeric keys, the operator often does not enter the pattern currently displayed on the screen. Thus, if the operator erroneously operates the numeric keys, a number that does not represent the desired pattern is entered, and the wrong pattern is selected.

Sewing machine and pattern selection apparatus


A system and method, for use in an implantable cardiac stimulation device, monitors progression or regression in heart disease such as congestive heart failure. The system includes a sensing circuit that derives an electrogram signal indicative of the electrical activity of the patient""s heart. A processor processes the electrogram signal to determine interchamber conduction delays which are then stored in memory. The stored interchamber conduction delays may be later retrieved by way of a telemetry circuit. Relative changes in the interchamber conduction delays, over time, are indicative of progression or regression in the heart disease. The relative changes in the interchamber conduction delays may be further used to automatically adjust pacing parameters of the implantable cardiac stimulation device.

The present invention is generally directed to an implantable device for monitoring the progression or regression of heart disease. The present invention is more particularly directed to a system and method for use in an implantable cardiac stimulation device which determines and stores interchamber conduction delays. Relative changes in the interchamber conduction delays, over time, are indicative of the progression or regression of the heart disease.
More people die of heart disease than any other single cause. One common form of heart disease is congestive heart failure.
Congestive heart failure (CHF) is a debilitating, disease in which abnormal function of the heart leads to inadequate blood flow to fulfill the needs of the body""s tissues. Typically, the heart loses propulsive power because the cardiac muscle loses capacity to stretch and contract. Often, the ventricles do not adequately fill with blood between heartbeats and the valves regulating blood flow may become leaky, allowing regurgitation or backflow of blood. The impairment of arterial circulation deprives vital organs of oxygen and nutrients. Fatigue, weakness, and inability to carry out daily tasks may result.
Not all CHF patients suffer debilitating symptoms immediately. Some may live actively for years. Yet, with few exceptions, the disease is relentlessly progressive.
As CHF progresses, it tends to become increasingly difficult to manage. Even the compensatory responses it triggers in the body may themselves eventually complicate the clinical prognosis. For example, when the heart attempts to compensate for reduced cardiac output, it adds sarcomeres to the myocardial cells, causing the ventricles to grow in mass in an attempt to pump more blood with each heartbeat. This places a still higher demand on the heart""s oxygen supply. If the oxygen supply falls short of the growing demand, as it often does, further injury to the heart may result. The additional muscle mass may also stiffen the heart walls to hamper rather than assist in providing cardiac output.
Current standard treatment for heart failure is typically centered around medical treatment using ACE inhibitors, diuretics, and digitalis. It has also been demonstrated that aerobic exercise may improve exercise tolerance, improve quality of life, and decrease symptoms. Heart transplantation is an option, but only in 1 out of 200 cases. Other cardiac surgery may also be indicated, but only for a small percentage of patients with particular etiologies. Although advances in pharmacological therapy have significantly improved the survival rate and quality of life of patients, patients who are refractory to drug therapy have a poor prognosis and limited exercise tolerance. Cardiac pacing has been proposed as a new treatment for patients with drug-refractory CHF.
In patients with heart failure and atrial fibrillation (AF), the heart has often remodeled due to the disease, such that there is increased fibrosis between myocardial cells, a lengthening of the cells, varying degrees of hypertrophy and dilation, and up and down regulation of various receptors that affect ionic balance, action potential conduction, and contraction. These variations in the AF and CHF substrates often result in conduction abnormalities that may manifest in arrhythmia, which may further worsen the substrate and thus the heart""s contraction synchrony.
Multi-chamber pacing (bi-ventricular or bi-atrial) has been proposed as an emerging therapy for the treatment of heart failure and atrial fibrillation. The patients who appear to gain the greatest benefit from this pacing therapy are those with the greatest dyssynchrony, since the benefit of multi-chamber pacing appears dependent upon chamber synchronization and/or appropriate sequencing.
It is desirable to have a system which would track the progression or regression of the patient""s disease, particularly as it relates to the success of any therapy in halting or reversing the remodeling. A good metric of the heart""s reverse remodeling is the degree to which the myocardium conducts the depolarization wave, since this relates directly to chamber synchrony.
The hemodynamic consequences of abnormal ventricular activation in dilated cardiomyopathy patients have been extensively studied. These studies account for the presence of major delay and nonuniformity in left ventricular (LV) contraction and relaxation in patients with poor LV function and high-degree interventricular conduction block. Hence, the degree of interventricular conduction delay may be used as a surrogate measurement for the disease state of heart. Additionally, patients prone to atrial fibrillation are likely to have a long interatrial conduction delay. Restoration of atrial chamber synchrony/sequencing may be critical in reducing the incidence of AF in these patients.
By tracking the progression or regression of heart disease, such as CHF, more closely, treatments could be managed more effectively. Commonly, patients with heart disease have an implanted cardiac stimulation device. Hence, it would be advantageous if the implanted cardiac stimulation device were able to aid in the tracking of the progression or regression of the heart disease. The present invention provides a system and method for use in such a device capable of tracking heart disease progression or regression by measuring interchamber conduction delays over time.
The present invention provides a system and method, for use in an implantable cardiac stimulation device, for monitoring progression or regression in heart disease such as congestive heart failure. A sensing circuit produces an electrogram signal indicative of the electrical activity of the patient""s heart. A processor processes the electrogram signal to determine interchamber conduction delays which are then stored in memory. The stored interchamber conduction delays may be retrieved by way of a telemetry circuit. Relative changes in the interchamber conduction delays, over time, are indicative of progression or regression in the heart disease.
The determined interchamber conduction delays may be the times between activations of corresponding ventricular or atrial chambers of the heart. The interchamber delays may alternatively be the times between the delivery of a pacing pulse to one chamber and the intrinsic depolarization of its corresponding chamber. The interchamber conduction delays may alternatively be the average of the right chamber to left chamber conduction delay and the left chamber to right chamber conduction delay.
The relative changes in the interchamber conduction delays may be further used for automatic pacing parameter adjustment. If the relative changes in the interchamber conduction delays indicate a decreasing trend, pacing rate may be decreased or AV delay may be increased to allow the patient""s heart to function more on its own without pacing intervention.

Implantable cardiac stimulation device for and method of monitoring progression or regression of heart disease by monitoring interchamber conduction delays


An adjustable mounting assembly for a power circuit breaker includes a frame having a first sidewall disposed opposite a first side of the housing of the power circuit breaker and a second sidewall disposed opposite the second side of the housing. At least one moveable block is disposed between the first and second sidewalls of the frame and the corresponding first and second sides of the housing. An adjustment mechanism, such as a jackscrew coupled to the moveable block, adjusts in order to move the block into engagement with the corresponding sides of the housing. A fastening mechanism, such as a lock screw, secures the moveable block and the frame with respect to the housing. The adjustable mounting assembly securely mounts the frame and the power circuit breaker within a switchgear enclosure in order to resist damage potentially caused by an impact force sustained thereby.

1. Field of the Invention
The present invention relates generally to electrical switching apparatus and, more particularly, to a circuit breaker including an adjustable mounting assembly. The invention also relates to an adjustable mounting assembly for circuit breakers.
2. Background Information
In certain applications, such as, for example and without limitation, naval applications (e.g., without limitation, water-based vehicles, such as ships, boats, aircraft carriers, other vessels for travel on water, and submarines, or other vehicles for travel under water), electrical equipment must be designed to withstand large shock loads (e.g., up to about 1000 times the force of gravity, or more). Such shock loads include, for example, impact loads resulting from a direct hit by a torpedo, depth charge, missile, other ammunition or impact force, as well as residual or aftershock loads caused, for example, by a nearby indirect explosion, such as the detonation of a depth charge. All shock loads can severely damage the electrical equipment. Accordingly, electrical components for such applications must be designed to withstand much larger loads than typically experienced by electrical equipment employed in conventional civilian or commercial applications.
For instance, a shock load of about 1000 times the force of gravity would be expected to crack or otherwise damage the molded (e.g., without limitation, plastic) housing of a commercial power circuit breaker. Additionally, it is generally well known that power circuit breakers are typically large in size and relatively heavy and are, therefore, often mounted with other switchgear in a cabinet or other enclosure. Accordingly, in order to facilitate insertion and removal of the circuit breakers with respect to the enclosure, power circuit breakers are typically mounted within a frame, known as a cassette, which may be drawn into and out of the cabinet. Hence, the "draw-out" designation is commonly associated with this type of switchgear configuration. In addition to the aforementioned undesired cracking of the molded housing of the circuit breaker, large shock loads could further cause the power circuit breaker to vibrate within, or separate or break-away from the cassette.
There is, therefore, room for improvement in circuit breakers for use in applications where the circuit breaker must be capable of withstanding a high load, such as a shock load, and in adjustable mounting assemblies for such circuit breakers.

Electrical switching apparatus and adjustable mounting assembly therefor


An ignition system for an internal-combustion engine includes an ignition coil and an ignition control circuit. The ignition coil includes a primary coil and a secondary coil. The ignition control circuit includes a capacitor. The ignition control circuit employs a capacitor discharged ignition method, whereby the ignition control circuit is configured such that electrical charge, with which the capacitor is charged, is discharged into the primary coil to drive the ignition coil. A coupling coefficient, which indicates a degree of magnetic coupling between the primary coil and the secondary coil, is set in a range of 0.9 to 0.97. k, which is the coupling coefficient, is provided using a formula k=(1−L1′/L1)1/2, wherein L1 is an inductance of the primary coil and L1′ is an inductance of the primary coil when the secondary coil is short-circuited.

1. Field of the Invention
The present invention relates to an ignition system for an internal-combustion engine.
2. Description of Related Art
In an ignition system used in a vehicle, voltage is applied to a primary coil of an ignition coil using an igniter, into which an ignition control circuit having a switching element and the like is incorporated. In the ignition coil, when voltage is applied to the primary coil and then the voltage is stopped in response to a pulsed spark generating signal from an ECU (electronic control unit), an induction field is formed, thereby generating high-voltage induced electromotive force (counter electromotive force) in a secondary coil. Accordingly, a spark is generated between a pair of electrodes in a spark plug, which is attached to the ignition coil.
In order to increase an amount of electricity passed through the primary coil, electrical charge, with which a capacitor is charged, is discharged into the primary coil using the ignition control circuit, in which a CDI (capacitor discharged ignition) method is employed. For example, an ignition system of multispark type, which realizes ignition performance that is the same or more than a combination of a multiple ignition method (by which an energy accumulation coil is employed, and the energy accumulation coil and the primary coil are alternately switched on and off, to discharge electrical charge) and the capacitor discharged ignition method, is disclosed in JP2811781B2 (corresponding to U.S. Pat. No. 5,056,496). In the ignition system of multispark type, a discharge time, during which electrical charge is discharged into the primary coil, is stabilized, by switching on and off the energy accumulation coil and the primary coil alternately.
However, when the primary coil is energized using the ignition control circuit, in which the CDI method is employed, a distinctive high-frequency voltage component attributed to the capacitor overlaps with output voltage of the secondary coil. In an output voltage waveform of the secondary coil shown in FIG. 7, when generation timing of a peak Vt of the high-frequency voltage component overlaps with generation timing of a peak V2max of a spark voltage V2 in the secondary coil, the peak V2max necessary to the secondary coil may not be ensured.

Ignition system for internal-combustion engine


A pseudo non-addressable alarm system that uses addressable notification appliances and/or detectors is disclosed. In one aspect, the addressable notification appliances and/or detectors may be entirely automatically (or partially automatically) grouped. One manner of automatic grouping is to use the wiring of the pseudo non-addressable system in order to automatically form the groupings of notification applications, such as grouping the notification appliances based on the signal line circuit to which they are connected. In another aspect, labels for the notification appliances and/or detectors in the pseudo non-addressable system may be entirely automatically (or partially automatically) generated. The labels may be automatically generated based on wiring of the pseudo non-addressable system and/or based on grouping information (such as grouping based on the particular signal line circuit to which the notification appliance is connected).

Typical fire alarm systems include a number of fire detectors positioned throughout a building (and/or campus). Signals from those detectors are monitored by a system controller, such as a fire alarm control panel ("FACP"). The FACP, upon sensing an alarm condition, sends commands to one or more notification appliances to alert occupants in one section of the building, in multiple sections of the building, or in all sections of the building. Notification appliances can output a visual notification, an audible notification, or both. Examples of notification appliances include, but are not limited to strobes, horns, speakers, and the like. Notification appliances are typically connected across common power lines on a notification appliance circuit ("NAC").
Fire alarm systems NACs may be classified as: (1) including non-addressable notification appliances ("non-addressable NAC"); and (2) including addressable notification appliances ("addressable NAC"). Non-addressable notification appliances do not have an address, and, therefore, the FACP cannot communicate with a particular notification appliance. All of the non-addressable notification appliances on a single circuit are activated at the same time, for example by applying power to the circuit. In the addressable system, on the other hand, each notification appliance has a uniquely assigned address, enabling the FACP to send communications to and receive communications from a particular notification appliance.
Each type of fire alarm system has benefits and drawbacks, such as in terms of installation, configuration, and operation. With regard to installation, the non-addressable alarm system is typically more expensive to install in terms of wiring than an addressable alarm system. The non-addressable alarm system is bound to the particular wiring of the system, e.g. a single loop of wiring or linear wiring with each appliance wired in series, so that the wiring may be supervised for open circuit faults. Also, due to the lack of uniquely assigned addresses, notification appliances need to be wired to the proper NAC in order to be properly activated by the FACP. In contrast, an addressable alarm system may be installed without regard to the particular wiring in a building since each appliance is individually supervised to detect open circuit faults. In this way, the installer may lay the wiring as is most convenient (such as by using "T" taps).
With regard to configuration, the addressable alarm system requires much more manpower than the non-addressable alarm system. For example, configuration of the addressable alarm system requires setting a unique address at each notification appliance (such as through switches or other type of means). As another example, configuration of the addressable alarm system requires entering device identification information (such as a label) for each notification appliance. As still another example, configuration of the addressable alarm system may require grouping of the notification appliances. Unlike non-addressable notification appliances (which are activated by modifying the power to the NAC to which they are connected), addressable notification appliances need not be grouped based on wiring. Instead, the group(s) to which each addressable notification appliance is to be assigned be manually designated so that the FACP can simultaneously turn a group of addressable notification appliances on/off at the proper times. Such a grouping is called a virtual NAC ("VNAC"), with each of the addressable notification appliances in the VNAC being "turned on" by the FACP, preferably using a single group-directed command.
With regard to operation, the addressable alarm system has advantages over the non-addressable alarm system. As merely one example, advanced diagnostics are available in the addressable alarm system that are not available in the non-addressable alarm system. For example, the FACP may send a command to an addressable notification appliance to perform a self-test. The addressed notification appliance may perform the self test, and then report back the results of the test to the FACP.
Even though installation is easier and operation is better using an addressable alarm system, a majority of fire alarm systems are non-addressable because configuring an addressable alarm system is so much more time-consuming and expensive.

This patent is subject to a terminal disclaimer.


A storage element includes a storage layer that stores information on the basis of a magnetization state of a magnetic material; a fixed magnetization layer that has a magnetization serving as a reference of the information stored in the storage layer; an interlayer that is formed of a nonmagnetic material and interposed between the storage layer and the fixed magnetization layer; a cap layer that is provided to be adjacent to the storage layer and opposite to the interlayer; and a metal cap layer that is provided to be adjacent to the cap layer and opposite to the storage layer.

The present disclosure relates to a storage element and a storage device incorporating the storage element. The storage element includes a storage layer which stores a magnetization state of a ferromagnetic layer as information and a fixed magnetization layer in which a magnetization direction is fixed, and changes the magnetization direction of the storage layer by the flow of an electric current.
Along with the dramatic progress of various kinds of information devices from mobile terminals to high-capacity servers, memory and logic elements configuring the information devices demand higher performance such as high integration, high speed, and low power consumption. In particular, the progress of semiconductor nonvolatile memories is remarkable and flash memories are becoming more widely used as high-capacity memory almost as if to eliminate hard disk drives from the market. Meanwhile, anticipating the progress in code storage memory or working memory, FeRAM (Ferroelectric Random Access Memory), MRAM (Magnetic Random Access Memory), PCRAM (Phase-Change Random Access Memory) and the like have been studied so as to replace NOR flash memory, DRAM and the like, which are currently used in general, therewith. Some of these memory types are already in practical use.
Among these, since MRAM records data on the basis of the magnetization direction of a magnetic material, rewriting can be performed rapidly and almost unlimitedly (1015 times or more). Therefore, the MRAM is already used in the fields of industrial automation, airplanes, and the like. Although being expected to be developed as code storage memory or working memory in the future due to the high-speed operation and the reliability thereof, actually there are problems with MRAM in realizing low power consumption and high capacity. These problems are caused by the recording principal of the MRAM in which a current is respectively made to flow through two types of address interconnects (word line and bit line) almost intersecting with each other and magnetization of a magnetic layer of a magnetic storage element, which is located at the intersection of the address interconnects, is reversed by a current electric field generated from each of the address interconnects, thereby recording information. That is, this is a fundamental problem due to the method of reversing the magnetization by the electric current magnetic field generated from the interconnects.
As a solution to this problem, a recording not using the current magnetic field, that is, a method of reversing the magnetization without using a current magnetic field has been discussed. Among these, research relating to spin torque magnetization reversal has been vigorously carried out (for example, refer to Japanese Unexamined Patent Application Publication No. 2003-17782, U.S. Pat. No. 6,256,223, Japanese Unexamined Patent Application Publication No 2008-227388, PHYs. Rev. B, 54.9353 (1996), and J. Magn. Mat., 159, L1 (1996)).
Similar to MRAM, storage elements using spin torque magnetization reversal are in many cases configured with an MTJ (Magnetic Tunnel Junction). This configuration uses a phenomenon that, when spin polarized electrons which pass through a magnetic layer fixed in a given direction enter into another free magnetic layer (where the direction is not fixed), a torque is applied to the magnetic layer (this phenomenon is also referred to as a spin transfer torque). In this case, when a current equal to or greater than a given threshold value is made to flow, the free magnetic layer is reversed. 0 and 1 are rewritten by changing the polarity of the current.
The absolute value of the current for the reversal is equal to or less than 1 mA for an element in the scale of about 0.1 μm. In addition, since this current value reduces in proportion with the element volume, scaling is possible. Furthermore, since a word line which is necessary for generating the recording current magnetic field in the MRAM is not necessary, there is also an advantageous effect in that the cell structure is simple.
Hereinafter, the MRAM using spin torque magnetization reversal is referred to as ST-MRAM (Spin Torque-Magnetic Random Access Memory). Spin torque magnetization reversal may be sometimes referred to as spin injection magnetization reversal. ST-MRAM has attracted much attention as a nonvolatile memory which can realize low power consumption and high capacity while keeping the advantageous effect of MRAM of performing rewriting rapidly and almost unlimitedly.


An imaging detector (214) includes a scintillator array (216) including a scintillator element (228) and a material (230) and a photosensor array (218) including a detector element (222) having a light sensitive region (224) and a non-sensitive region (226). The light sensitive region is separated from the scintillator element by a gap, the light sensitive region is in one-to-one mechanical alignment with the scintillator element, and the non-sensitive region is in mechanical alignment with the material. The detector further includes structure (234) that includes one or more material free channels. The structure is located between the non-sensitive region and the material and not between the light sensitive region and the scintillator element. An optical adhesive (232) is located in the gap, filling the entire gap, and mechanically and optically coupling the light sensitive region and the scintillator element.

A computed tomography (CT) scanner includes a rotating portion rotatably supported by a stationary portion. The rotating portion supports an x-ray tube, which emits radiation that traverses an examination region, and a detector array that detects radiation traversing the examination region. A conventional integrating detector array includes a scintillator array optically coupled to a photodiode array. The scintillator array absorbs x-ray photons and emits light photons indicative thereof, and the photodiode array receives the light photons and generates electrical signals indicative thereof and hence the absorbed x-ray photons. A reconstructor reconstructs the signals and generates volumetric image data indicative of the examination.
Various approaches have been used to couple the scintillator and detector arrays. One approach is discussed in connection with FIGS. 1A and 1B. FIG. 1A shows a two dimensional photodiode array 102. Generally, such arrays are 16×16 up to 16×64; however, for explanatory purposes, the illustrated array is a 2×2 array with four generally square shaped detector elements 104. Each detector element 104 includes a surface 106 with a light sensitive region 108 surrounded by a non-sensitive region 110. A drop of an optical adhesive 112 is placed at a junction 114 where the four detector pixels 104 meet. A scintillator array 116 is then lowered onto the photodiode array 102. As the scintillator array 116 physically contacts the optical adhesive 112 and applies a force thereon, the optical adhesive 112 radially spreads from the junction 114 over the surface 106, including both the light sensitive regions 108 and the non-sensitive regions 110. FIG. 1B shows the scintillator array 116 lowered onto the photodiode array 102 with the optical adhesive 112 there between.
With this approach, as well as other approaches, optical adhesive voids (or air bubbles) may form and be trapped between the scintillator array 116 and the photodiode array 102. Unfortunately, such voids may decrease light collection efficiency, i.e., inhibit or prevent light transmission from the scintillator array 116 to the light sensitive regions 108 of the photodiode pixels 104. Furthermore, it can be difficult to control the final optical adhesive thickness between the scintillator array 116 and the photodiode array 102, and excess adhesive 118 will squeeze out of the sides, as shown in FIG. 1B, and must be subsequently removed. Moreover, this approach requires fixtures to hold the scintillator array 116 and the photodiode array 102 in place, and the automation machinery generally is expensive.


Various embodiments of the invention determine whether paths of a first graph satisfy a constraint based on a plurality of sub-graphs of the first graph. Each graph is a directed acyclic graph of nodes and arcs. The first graph and a second graph are generated in a memory arrangement, with the first graph and the second graph having a shared sub-graph, and each path of the paths of the first graph is constrained by the constraint unless the path is a path of the second graph. The plurality of sub-graphs of the first graph are generated in the memory arrangement with each of the plurality of sub-graphs not including any path of the second graph and each of the paths of the first graph that is not a path of the second graph being included in at least one of the plurality of sub-graphs.

A directed acyclic graph (DAG) is a useful representation for verifying compliance to a constraint that may be a set of individual constraints. Example constraints are a time constraint, such as a schedule for completing a project with multiple dependencies, and a distance constraint, such as a requirement that certain interrelated components must be arranged to fit within an available space.
Another example for a timing constraint is static timing analysis of an electronic circuit, which may have the requirement that particular circuit paths have a cumulative delay along the path that is less than or greater than a given value, which may be explicitly or implicitly specified. For static timing analysis, the DAG may have nodes representing circuit elements and arcs representing connections between the circuit elements. Each arc or node may have an associated delay value representing the propagation delay through the arc or node. By adding the delay values for the arcs and/or nodes along the path, the total propagation delay along the path may be determined and compared with the path requirement.
A DAG has a set of source nodes and a set of sink nodes. Typically, a constraint for a DAG is a constraint between some of the source nodes and some of the sink nodes. Numerous paths may exist between a particular source and a particular sink. A graph search of the DAG may efficiently determine the worst case paths. Enumeration of all paths represented by the DAG may be avoided because the DAG satisfies the constraint if the worst case paths satisfy the constraint.
A relaxation of a constraint may specify that certain paths between a source and a sink may be disregarded in verifying compliance to the constraint, or may have a relaxed requirement. The relaxation overrides the constraint. Example relaxations are multi-cycle paths and false paths for a synchronous electronic circuit, or false or irrelevant paths in an asynchronous circuit.
An example multi-cycle path in a synchronous electronic circuit may have a source that is known, a priori, to change the transmitted value only in even clock cycles and a sink that is known, a priori, to ignore the received value in odd clock cycles. Thus, this particular path may provide correct circuit operation when the cumulative delay along the path is as much as two clock periods. A constraint that paths have a total delay of less than one clock period may be relaxed for the multi-cycle path.
An example false path in a synchronous electronic circuit may be an apparent path that is impossible to exercise. For example, a multiplexer control signal may control two separate multiplexers, and a path from a source to a sink may pass through a different respective input of each multiplexer. The propagation of signal values along the path is then interrupted, regardless of the value of the multiplexer control signal, by one of the multiplexers. Because a value change of the source cannot propagate along the path to a value change of the sink, the cumulative delay along the path may be unconstrained. A constraint that paths have a total delay of less than one clock period may be relaxed for the false path.
One approach to representing a relaxation of a constraint is to perform node replication and select arc replication and removal within the DAG to isolate the relaxation paths from the remaining constraint paths. However, the duplicated nodes in the DAG may complicate other graph operations, such as node searches.
The present invention may address one or more of the above issues.

Representation of a relaxation of a constraint by graph replication


An improved folding seat which can be attached to many different designs of walkers including rigid types and foldable walkers including a folding walker having a frame consisting of a left side A-frame and a right side A-frame with each side A-frame having a fixed vertically extending front leg, a folding vertically extending rear leg and a side brace connecting the front and rear legs and a cross brace for pivotally connecting the left side A-frame to the right side A-frame, in a manner that enables the side A-frames to be moved between closed and open positions; and a bifold seat panel for pivotal attachment to the frame means having two pivotally connected seat panels, a pair of articulated arms including arched cross rods connecting a right articulated arm to a left articulated arm having a combination handle and center cross rod extending between a first central pivot point and a central pivot point, support devices for supporting the seat means on the frame including back support clamping devices for pivotally supporting the back of the bifold seat panel, front support belt for supporting the front of the bifold seat panel to permit the seat to be moved from a flat in-use position to a raised folded position stored against the front of said folding walker permitting use as a walker.

The present invention relates to an improved folding seat for use with folding walkers, and particularly to a seat kit that can be quickly and simply attached to many walkers and affords instant security and comfort when a user of the walker feels faint or fatigued. Prior art folding walkers provide for limited mobility for users in need of assistance having limited reserve of strength. By permitting walking for patients otherwise committed to a wheel chair, the patient achieves more independence, however the need for assistance from care givers is still needed, particularly in the event the user tires and seeks a seated rest. Accordingly walkers are commonly used in home, extended health care facilities or hospitals because they help to reduce the personnel needed to assist persons having limited mobility.
Applicant is aware of other prior art devices which provide different forms of foldable seats having some of the operational features of the present invention for use with conventional walkers. Reference is hereby made to U.S. Pat. Nos. 4,826,240, 4,907,839, 4,643,211, 2,798,533, 5,224,721, and 1,448,783. The above noted U.S. Patents are representative of the current state of the art with respect to the subject matter of the present invention. The above noted prior art includes many problems or disadvantages. For instance, they are typically designed for use with standard rigid walkers and employ uncomfortable seat materials such as flat hard seat panels. In addition, with respect to the attachment devices, they are often flawed by lack of ease of attachment to structural members of the walker frame elements which limit their ease. Another common flaw is the lack of structural soundness and reliability to provide support for an extended period of time. Furthermore, the prior art foldable seats typically require specifically directed activity on the part of the user for moving the seat from an inoperative position to an operative position and insuring that the seat is in a secure condition. A further disadvantage of prior art folding seats is that they are not intended to be used for an extended period of time such as viewing television programs in a community area where seating is limited.
Accordingly, it is an object of the invention to provide for the rapid and easy movement of a collapsible seat into an operative position from a retracted inoperative position with a minimum of articulation of the user's hand. A critical feature accordingly must use one or both hands on the walker in addition to both feet for mobility. Accordingly, at such time as the user wishes to place the collapsible seat into an operative position, only one hand typically is available for use, the other being used to hold the walker for balance. Furthermore, users typically have impaired vision as well as reduced strength such that it is important that the folding seat have a handle for movement of the foldable seat into an operative position that is both easy to see and easy to operate in a "fail safe" mode.
Accordingly, it is desirable to provide for a new and improved folding seat apparatus for use with walkers which is lightweight, easy to operate and which is configured to fit different types of walkers (both folding and standard fixed) to a retrofit seat kit designed for different types of walkers and to a method of installing the kit which overcomes at least some of the disadvantages of prior art.


A spherical integrator has beam input and output apertures. The output aperture is opened at a position to which incident beam does not directly strike. The integrator has a curved inner surface which is a uniform diffusion surface. A galvanometer scanner has a mirror capable of adjusting a reflection angle of the beam from a light source such that a luminous energy beam reflected by the mirror to the input aperture is quantitatively varied. Beam from the light source is reflected by the mirror of the scanner to the input aperture of the integrator which diffuses and integrates the incident beam and outputs it through the output aperture.

The present invention relates to a device for controlling luminous energy used for example in a movie film printer or a telecine.
Known as device of this type are a device for varying an area of an aperture by a mechanical stop interposed between a light source and an object, a device for electrically controlling luminous energy from a light source, a device with an optical modulator capable of electrically varying transmissivity and a device for directing beam to any of filters each having a different transmissivity.
When color tune is to be also adjusted upon control of luminous energy, there have been used a device (utilizing so-called subtractive process) with color filters to vary color tone; or a device (using so-called additive process) in which spectroscope means such as color filter, dichroic mirror, diffraction grating or prism separates light into a plurality of lights with monochromatic colors (in general, primary colors: red, green and blue), each of the color lights is controlled with respect to luminous energy by the above-mentioned luminous energy controlling device and such color lights controlled with respect to luminous energy are mixed again.
In the conventional devices for controlling luminous energy, generally the luminous energy is detected by an optical sensor disposed adjacent to an object.
In the device for varying the area of the aperture by the mechanical stop interposed between the light source and the object, when the area of the aperture is varied over a wide range, response for aperture control is slow due to inertia of the mechanical stop. When the area of the aperture is varied over a small range, control with a high degree of precision cannot be ensured.
In the device for electrically controlling luminous energy from the light source, color tone inevitably varies depending upon the luminous energy and concurrently temperature variation of the light source occurs so that stabilized control cannot be ensured.
In the device with the optical modulator capable of electrically varying transmissivity, loss of light is so high that the device is hardly usable in a movie film printer, a telecine or the like.
The device for directing beam to any of filters each having a different transmissivity is also hardly usable in a movie film printer, a telecine or the like, though it may be applicable to control of luminous energy of fine beam entering into and emitting from for example an optical fiber.
Furthermore, in the device for adjusting color tone by the color filters, whenever color tone is to be varied, the color filter used must be replaced by a suitable color filter corresponding to the color tone to be obtained. As a result, it is difficult to vary color tone within an extremely limited time period.
In the device in which light is separated by spectroscope means into a plurality of monochromatic color lights, each color light being controlled with respect to luminous energy by the luminous energy controlling device, the color lights controlled with respect to luminous energy being mixed again, rays of light with different wavelengths pass different paths so that outgoing beam is affected by partial differences of reflection, transmission and dispersion characteristics between the paths and consequently color distortions may be developed.
In view of the above, the present invention has for its object to provide a device for controlling luminous energy which is fast in response and has a higher degree of control accuracy and which can stably attain an outgoing beam with uniform luminous energy distribution over cross section of the beam and with desired intensity and to provides a device for controlling luminous energy which can also adjust color tone without causing color distortions.


A seal assembly for use in a turbomachine, the seal assembly comprising an oil seal plate; a rotatable component which defines a central axis and is received in a central aperture of the oil seal plate; and an annular seal which comprises a base and a sealing portion, the base being held by the rotatable component; wherein the sealing portion is configured to form a seal with the oil seal plate when the rotatable component and annular seal are rotating below a predetermined rotational speed; and wherein the sealing portion is configured to move radially outwards with respect to the central axis such that the sealing portion loses contact with the oil seal plate when the rotatable component and annular seal are rotating above the predetermined rotational speed.

Turbochargers are well known devices for supplying air to the intake of an internal combustion engine at pressures above atmospheric pressure (boost pressures). A conventional turbocharger comprises an exhaust gas driven turbine wheel mounted on a rotatable shaft within a turbine housing. Rotation of the turbine wheel rotates a compressor wheel mounted on the other end of the shaft within a compressor housing. The compressor wheel delivers compressed air to the intake manifold of the engine, thereby increasing engine power.
The turbocharger shaft is conventionally supported by journal and thrust bearings, including appropriate lubricating systems, located within a central bearing housing connected between the turbine and compressor wheel housing. It is desirable to provide an effective sealing arrangement at each end of the rotating shaft to prevent oil leakage from the central bearing housing into the compressor or turbine housing.
At the compressor end of the turbocharger, during normal operation, the sealing arrangement should be able to withstand the increasingly high boost pressures that are delivered by modern turbochargers. The pressure of the bearing housing is effectively the same pressure as the engine oil sump (typically around 100 mbar) and there is thus a pressure gradient between the bearing housing and the compressor housing which prevents the leakage of lubrication oil from the bearing housing into the compressor housing. The sealing arrangement typically comprises one or more ring seals arranged between the shaft and the bearing housing and received in respective grooves, in the manner of piston rings. The seals are arranged with a radial clearance so as to allow free rotation of the shaft but to restrict the flow to allow the pressure difference between the bearing housing and the compressor housing and/or the turbine housing to remain.
Low shaft speed, such as when the engine is idling or during exhaust braking, results in a reduction in pressure behind the compressor wheel. The low (or even negative) boost pressure at the compressor end can drop below the pressure in the bearing housing. As a result of the negative pressure difference over the seals (PDOS), oil is able to leak along the turbocharger shaft in the bearing housing, past the seals and into the compressor housing. The leakage of oil may be significant, for example, if idling or operating in engine braking mode occurs for extended periods of time. Leakage of oil into the compressor housing is undesirable as it contaminates the pressurised air entering the engine intake manifold.
It is one object of the present disclosure to obviate or mitigate the aforesaid disadvantage.


The present application discloses biopolymer-based ink formulations that are useful for inkjet printing and other applications. Related methods are also disclosed.

Inkjet printing is a type of computer-based printing that creates a digital image by propelling droplets of ink onto a substrate, typically paper. The concept of inkjet printing has been around for over a century but was made readily accessible to consumers in the latter half of the 20th century. Inkjet printing can be also employed for direct material deposition, which is an emerging manufacturing technique today.
The field of computer-assisted printing has seen vast technological advancement in recent years, including the 3D printing technology used to fabricate computer-designed objects by so-called "additive manufacturing." Typically, the process of 3D printing involves serial printing (i.e., layering) of particles or 3D dots comprised of materials, such as thermoplastics, metal alloys, and plasters.
The inkjet technology as applied to biological materials, however, generally faces a number of technical obstacles.