Abstract: A spindle motor using a hydraulic bearing is provided, wherein an R-face or C-face is formed on each of upper and lower edges of an outer periphery of a rotating disk portion rotatable integrally with a spindle, and the R-face or C-face is formed into a mirror-finished surface having a surface roughness of 0.3 s or less in Ra, preferably, 0.1 s or less in Ra. Alternatively, a recess may be formed in a portion, facing to each of the upper and lower edges of the outer periphery of the rotating disk portion, of an inner wall surface of the hydraulic bearing. Such a spindle motor provides a disk drive capable of suppressing a variation in rotational speed of the spindle motor caused by tilting of the spindle due to vibration and impact, thereby ensuring a stable recording or reproducing operation.

Abstract: In a disk reading/writing device, a chucking mechanism holds two types of disks having different outer diameters. The chucking area of a small-diameter disk is set to be less then the chucking area of a large-diameter disk. The disks are focused by an optical pickup placed on the side opposite the chucking surface. This configuration makes it possible to enlarge the data area of the small-diameter disk and to perform reading and writing from and onto the small-diameter disk with an enlarged data area.

Abstract: An optical element having a substrate formed by an optical material and able to improve mechanical strength, wherein the substrate has a convex part functioning as a convex lens, a flat part positioned around the convex part, and an outer circumference part positioned around the flat part. The thickness of the substrate at the outer circumference part is greater than that of the substrate at the flat part.

Abstract: An image recording apparatus that can easily obtain a train of parallax images to be for preparing a holographic stereogram, without the necessity of laying rails. The apparatus comprises a camera and a position data recording section. The camera takes pictures of an object. The position data recording section for recording position data when the camera takes pictures of an object.

Abstract: An optical head has achromatic lenses which a blue or blue-violet laser beam from a laser diode strikes, object lenses for condensing the laser beam passing through the achromatic lenses on an optical disc, lens holders and for holding the achromatic lenses and the object lenses so that their optical axes coincide, and actuators and for moving the lens holders in the focus direction and/or tracking direction of the optical disc. The lens holders are fixed to each other and the lenses are moved as one part by the actuators.

Abstract: A frequency range bounder for limiting the frequency of a voltage controlled oscillator uses a multiplexer that responds to comparator inputs indicating whether an input control signal will allow the oscillator frequency to go beyond a predetermined range. If the control signal keeps the frequency within the range, the control signal is sent directly to an oscillator driver. If the control signal is above or below the range, the multiplexer outputs an alternative value as the control signal. As a result, the oscillator frequency is prevented from extending beyond an allowable tolerance range.

Abstract: When GaN or other nitride III-V compound semiconductor layers are grown on a substrate such as a sapphire substrate, thickness x of the substrate relative to thickness y of the nitride III-V compound semiconductor layers is controlled to satisfy 0<y/x≦0.011 and x≧450 &mgr;m. Alternatively, if the maximum dimension of the substrate is D (cm), its warpage H is in the range of 0<H≦70×10−4 (cm), and Z=y/x, D is controlled to satisfy the relation 0<D<(2/CZ)cos−1(1−HCZ), where C (cm−1) is the proportionality constant when the radius of curvature of the substrate &rgr; (cm) is expressed as 1/&rgr;=CZ.

Abstract: A turntable for mounting an optical disk without occurrence of eccentricity including: a fixed portion (48) fitted in a centre hole of the optical disk; a movable portion (50) fitted in the center hole with the fixed portion (48) as a reference so as to be elastically deformed to correct eccentricity when the optical disk is mounted; a shaft portion (42) molded integrally with the fixed portion (48) and into which is inserted a drive shaft (14a) of a drive motor for rotating a turntable (12) continuously; and a plate spring (60) for returning, when the optical disk is not mounted, the movable portion (50) from a position when the optical disk is mounted to a position when not mounted. The plate spring (60) is secured to the shaft portion (42) directly.

Abstract: The invention provides a motion vector conversion method by which the coding efficiency in image coding of MPEG4 in an image information conversion method can be further augmented. In the motion vector conversion method for an image information conversion method, every other one of P frames of a bit stream of MPEG2 is dropped to produce a bit stream of MPEG4 of a reduced frame rate and a low bit rate. Also for motion vector modification, information of each of macro blocks and between blocks in the inputted bit stream representative of image compression information of MPEG2 is stored in advance, and motion vectors of a P frame immediately preceding to each P frame to be dropped are duplicated based on the stored information. Then, the duplicated motion vectors are extended to twice in the temporal direction to produce motion vectors of MPEG4 converted from an intraframe of MPEG2.

Abstract: A single crystal silicon is graphoepitaxially grown using a step formed on a substrate as a seed by a catalyst process, and the obtained single crystal silicon layer is used for a dual gate type MOSTFT in an electro-optical apparatus such as a display section of a peripheral driving circuit integration type LCD. A single crystal silicon thin film having high electron/hole mobility is formed into a uniform film at a relatively low temperature, which enables the manufacturing of an active matrix substrate incorporated with a high-performance driver which can be used in a TFT display.

Abstract: A first optical device according to the present invention comprises a base made of a first optical material and a second optical material having a refractive index different from that of the first optical material, and the base has a concavity, and the second optical material is filled in this concavity. A second optical device according to the present invention comprises a base made of a first optical material and a second optical material having a refractive index different from the first optical material, and the base comprises first and second faces facing each other, a first concavity is formed in the first face and a second concavity is formed in the second face, and the second optical material is filled in the first and second concavities.

Abstract: Substrates suitable to manufacture and products of a thin film semiconductor device are provide, by at first preparing a manufacturing substrate having a characteristic of being capable of enduring a process for forming a thin film transistor and a product substrate having a characteristic of being suitable to direct mounting of the thin film transistor in a preparatory step, then applying a bonding step to bond the manufacturing substrate to the product substrate for supporting the product substrate at the back, successively applying a formation step to form at least a thin film transistor to the surface of the product substrate in a state reinforced with the manufacturing substrate and, finally, applying a separation step to separate the manufacturing substrate after use from the product substrate.

Abstract: A main picture is displayed in monochrome in a main picture display area by emission of a first phosphor layer formed of a white emission phosphor. A second phosphor layer formed of a phosphor different from the first phosphor layer is provided in a region different from the first phosphor layer. Icons are displayed in the icon display area in a color different from the main picture by emission of the second phosphor layer.

Abstract: A brushless motor-driving circuit is disclosed which includes an initializing element setting an initial rotating speed, an oscillating element for generating a frequency corresponding to the initial rotating speed set by the initializing element, a frequency-controlling element for causing the frequency generated by the oscillating element to change from the frequency corresponding to the initial rotating speed to a frequency corresponding to a constant rotating speed, a driving-signal-generating element for generating driving signals having a plurality of phases based on the generated frequency of the oscillating element, and a driving element for driving coils having a plurality of phases based on the driving signals having the plurality of phases generated by the driving-signal-generating element.

Abstract: When a Levenson phase-shift mask is manufactured, the relationship of optical conditions (numerical aperture, partial coherence factor, and others) of an optical system of an exposure device used for exposure and a mask structure (amount of excavation of a substrate, thickness of a phase shifter, or the like) with displacement of a pattern to be transferred by exposure is sought by simulation, and optical conditions and a mask structure that limit displacement of the pattern within a required range are selected, taking manufacturing errors of the mask into consideration. Then the selected optical conditions and mask structure are examined to determine whether they ensure a desired exposure tolerance and a desired focal depth, and this procedure is repeated until an acceptable result is obtained.

Abstract: An objective lens unit for an optical pickup used for recording and/or reproducing information signals from an optical disc. The objective lens unit includes a resin layer (21) having, sequentially from an object side, a first surface S1 as an aspherical surface and a second surface S2 as an aspherical surface, at least one of the first surface and the second surface including a diffractive surface, and a lens of glass (22) having the second surface S2 as an aspherical surface and a third surface S3 as an aspherical surface. The lens unit is corrected for the chromatic aberration on an image surface on the optical axis with respect to the light of a reference wavelength not larger than 420 nm within several nm of the reference wavelength, with the numerical aperture of the lens unit being not less than 0.8. This objective lens unit is able to converge the laser light close to the limit of diffraction on the image surface.

Abstract: A head drum device of the present invention prevents a magnetic tape (2) from clinging to the head drum device (3) due to electrostatic charge by using a carbon-containing synthetic resin as the material of an upper drum (33) in order to reduce the manufacturing cost for the upper drum. Also, setting the outside diameter of the upper drum (33) smaller than that of an intermediate drum (32) eliminates the need for a high-level of manufacturing precision in the manufacture of the upper drum (33). Thus, it is possible to reduce the manufacturing cost for the upper drum (33).

Abstract: A novel paging technology allows a group of subscribers to share and take advantage of bargain, promotion, and special pricing information that may otherwise be difficult to obtain or only useful for a very limited time. A service provider collects and stores such information. The information is then compared to a profile for each subscriber detailing what type of information that subscriber is interested in receiving. Information matching the interest profile of each subscriber this then transmitted to that subscriber's pager. Each subscriber's pager may include an input device, such as a virtual keyboard, so that each subscriber can submit information to the system to be shared with other subscribers.

Abstract: A luminescence crystal particle which emits light upon irradiation with an energy beam and which has a crystal defect density of 5×107 defects/cm2 or less in a region located from the surface of the luminescence crystal particle to a portion as deep as the energy beam reaches.

Abstract: A flash memory initialization sequence in a DTV set-top box of the type having a program-controlled microprocessor associated with a front panel board and a DTV board for processing at least part of an audio/visual television signal in which the sequence, upon application of start-up power, determines whether or not a selected file exists indicative of at least a partial formatting of the flash memory and causes the main DTV application to execute in the event the selected file exists. Conversely, where the selected file is not detected, the initialization sequence runs an initialization routine that at least formats a portion of the flash memory, thereafter creates the selected file indicative of the desired formating of the flash memory, and returns control to re-determine whether or not the selected file exists to cause the main DTV application to then execute.