Abstract: Embodiments of the invention prevent contact between a peripheral edge of a magnetic disk and a counter surface of a ramp when the magnetic disk is displaced. In one embodiment, a ramp is disposed near the peripheral side surface of a magnetic disk. The ramp has magnetic disk retainers each having slide surfaces and counter surfaces respectively facing the recording surfaces of the magnetic disk. Grooves or recesses are formed in the counter surfaces to define relief spaces. When the peripheral side surface of the magnetic disk is displaced toward the counter surface by shocks exerted on the magnetic disk drive, the relief space prevents the peripheral edge from coming into contact with the counter surface. Thus the amount of particles produced by the collision of the magnetic disk with the ramp can be reduced.

Abstract: A multi-layer information storage medium 600 includes: a data-reading surface; and eight recording layers 601 to 608 for recording data which is read out by using a blue-violet light beam. Each of the recording layers 601 to 608 has a user data area 610. A recording layer which is the most distant from the data-reading surface 601 includes a disk information area 26 and a defect management area 27 for recording management information concerning all of the recording layers 601 to 608.

Abstract: An immersion microscope objective lens of the present invention has: in order from an object, a first lens group G1 having positive refractive power and having a cemented lens of a plano convex lens having a plane facing the object and a meniscus lens having a concave surface facing the object, and a single meniscus lens having a convex surface facing the object; a second lens group having positive refractive power and having a plurality of cemented lenses; and a third lens group having negative refractive power and having a cemented meniscus lens having a concave surface facing an image, and a cemented meniscus lens having a concave surface facing the object. And the following conditional expressions 0.12<d0/f<0.25, 0.04<?Ct(p)??Ct(n)<0.09 and ?0.03<?hg(p)??hg(n)<0.00 are satisfied.

Abstract: An optical disk device is disclosed that includes loop gain adjustment means for finding the first tracking loop gain of a first region, and loop gain estimation means for estimating the second loop gain of a second region on the basis of the loop gain of the first region. Accordingly, it is possible to set the optimal tracking control loop gain for all regions. As a side benefit, good tracking control stability can be ensured regardless of the region, which improves the reliability of reproduction and recording.

Abstract: An optical disc apparatus according to the present invention includes a disc type recognizing section 109 for determining whether the optical disc 100 loaded is a first type, of which the number of information storage layers is less than a setting T (where T is an integer that is greater than two), or a second type, of which the number of information storage layers is equal to or greater than the setting T. Depending on whether the optical disc loaded has turned out to be the first type or the second type, the apparatus decides what to do as the read/write preprocessing (such as whether a fingerprint detection process needs to be performed or not).

Abstract: A process for producing a catalyst for hydrodesulfurization and isomerization of a sulfur-containing hydrocarbon oil, which comprises supporting palladium on a composition comprising a platinum-supported sulfated zirconia and alumina.

Abstract: The optical disk drive of the present invention can read data from multiple types of optical disks and includes: a motor for spinning a given optical disk; at least one light source for radiating light beams with multiple different wavelengths; at least one lens for converging each light beam onto the disk; a spherical aberration correcting section that can change the spherical aberration states of the beam; and a control section for controlling the operations of the motor, light source, lens and spherical aberration correcting section. The control section includes a disk type recognizing section that irradiates the disk with a light beam using the light source and the lens, thereby recognizing the type of the disk.

Abstract: An optical disk drive is designed to read and/or write data from/on a spiral string of tracks where land and groove tracks are alternated. The drive includes: a light source for radiating a light beam; a lens for converging the light beam; a mechanism for moving the lens; a photodetector for generating an electrical signal based on at least a part of the light beam reflected from the optical disk; and a control section for controlling the light source and the mechanism responsive to the electrical signal. While performing a seek operation by having the lens moved by the mechanism such that a target track, from/on which the data should start being read or written, is irradiated with the light beam, the control section tries to get a PLL locked by irradiating another track, which precedes the target track by at least one, with the light beam.

Abstract: The purpose is to move an observation field of view of a microscope without moving or changing an objective lens without varying position or state of a sample. A microscope optical system according to the present invention has a mirror that changes the direction of the optical path by reflection and locates in the optical path between an objective lens of the microscope and an image to be observed. The mirror is able to be tilted with changing the position of a reflecting surface of the mirror. Accordingly, the observation field of view is moved by tilting the mirror. In other words, the observation field of view can be moved without changing positional relation between the objective lens of the microscope and the sample.

Abstract: A magnetic field gradient is generated in a space, and a microparticle is flied downward in the space, thereby applying a magnetic force from the magnetic field gradient onto the microparticle. Then, a velocity and an acceleration of the microparticle due to the magnetic force are measured, thereby measuring a mass of the microparticle on the measured velocity and a magnetic susceptibility of the microparticle.

Abstract: An observation field of view of a microscope can be moved without moving or changing an objective lens and without varying position or state of a sample. A microscope optical system has a mirror that changes the direction of the optical path by reflection. The mirror is located in the optical path between an objective lens of the microscope and an image to be observed. The mirror can be tilted to change the position of a reflecting surface of the mirror. Accordingly, the observation field of view is moved by tilting the mirror without changing a positional relation between the objective lens of the microscope and the sample.

Abstract: The optical disc apparatus of this invention includes: an optical pickup, which irradiates an optical disc with a light beam and generates a light detection signal based on the beam reflected from the disc; a search section, which controls the pickup before data is written on a storage area of the disc, thereby adjusting the beam spot location and searching a reference one of information layers stacked for a defective area in the storage area of the disc; a defect decision section for detecting an error based on the detection signal and determining a portion of the storage area, where the error has occurred, as the defective area; a defect size measuring section for measuring the size of the defective area in an area of the reference layer and generating a defect information list indicating there is the defective area in the area of the reference layer; and a recording range control section for managing, by reference to the list, the storage area such that no data will be written on a perpendicularly projecte

Abstract: This optical disc drive can read and/or write data from/on an optical disc 20 with multiple information layers including first and second information layers. The drive includes: a light source 3, 4 that emits the light beam; an objective lens 1; an actuator 2 for moving the objective lens perpendicularly to the information layers; a focus error generator 7 for generating a focus error signal representing how much the light beam has been converged on a target one of the information layers; and focus control means for forming a focal point of the light beam on the target information layer by driving the actuator in accordance with the focus error signal. According to the present invention, while a focus jump is being made to shift the focal point of the light beam from the first information layer of the optical disc 20 to the second information layer thereof by moving the objective lens 1, wavelengths and/or numerical apertures for the light beam are changeable while the objective lens 1 is moving.

Abstract: An optical disk drive includes: a light source for producing a light beam; an objective lens for converging the light beam; an actuator for moving the objective lens with respect to an optical disk; a converging state detecting section for generating a focus error signal representing a converging state of the light beam on an information storage layer of the optical disk; and a focus control section for controlling the operation of the actuator such that the focus position of the light beam matches its target focus position as closely as possible in accordance with information about the target focus position and the focus error signal. The optical disk drive changes the target focus positions of the light beam when modes of operation are switched from a read mode into a write mode, or vice versa.

Abstract: The purpose is to provide an optical disc apparatus which can accurately calculate a gain for focus control. An optical apparatus (100) includes: an FE generator (20) for generating an FE signal; an AS generator for generating an AS signal (21); a normalization operator (22); an Fc filter (23); a selector (24); a spherical aberration setting device (34); an FE amplitude measuring device (30); an Fc pull-in instructor (52); an after-pull-in AS measuring device (40); and a gain operator (32). The optical apparatus obtains an amplitude of the FE signal before the focus is pulled in, and obtains a level of the AS signal after the focus is pulled in to adjust a focus gain.

Abstract: An optical disc drive according to the present invention can read and/or write data from/on an optical disc with information layers including first and second information layers (L0 and L1). The drive includes: an objective lens for converging a light beam; a lens actuator for driving the lens; a photodetector section that receives the beam reflected from the disc and converts it into an electrical signal; and a control section for determining the values of a first group of parameters, which are set to read data from the first layer (L0), and those of a second group of parameters, which are set to read data from the second layer (L1), during a disc loading process.

Abstract: An optical disk drive according to the present invention has the ability to read data from multiple types of optical disks, each of which includes at least one information storage layer. The drive includes: a driving mechanism 120, which is loaded with a selected one of the optical disks of the multiple types and which rotates the optical disk 102; an optical pickup 30 for irradiating the optical disk 102, which has been loaded into the driving mechanism 120, with a converged light beam, thereby generating an electrical signal based on light that has been reflected from the optical disk 102; and a control section (ODC 50) for controlling operations of the driving mechanism 120 and the optical pickup 30. The control section 50 includes a right/wrong side determining section for determining, by reference to the electrical signal generated by the optical pickup 30, whether or not the optical disk 102 has been loaded into the driving mechanism 120 with the other surface opposed to the optical pickup 30.

Abstract: An optical disc device of the present invention includes spherical aberration changing means for changing spherical aberration occurring on a converging position of a light beam converged by a lens, an actuator for moving the spherical aberration changing means in a relatively precise manner, and an actuator for moving the spherical aberration changing means in a relatively rough manner. The optical disc device drives a second actuator and a third actuator based on a signal of spherical aberration detecting means and performs control so that spherical aberration is almost 0. The third actuator moves the spherical aberration changing means based on a direct current component included in a signal of the spherical aberration detecting means, and the second actuator moves the spherical aberration changing means based on an alternating current component included in the signal of the spherical aberration detecting means.

Abstract: An optical disk apparatus comprises a focusing means for focusing a light beam on a recording medium having first and second information faces; means for moving a focal point of the light beam in a direction substantially perpendicular to the information faces of the recording medium; means for detecting a reflected light from the recording medium; means for detecting a focus condition of the light beam on the basis on an output signal from the reflected light detecting means; a focus control means for driving the focal point moving means on the basis of an output signal from the focus condition detecting means, and controlling the light beam so that the focus condition of the light beam becomes a prescribed focus condition; and a focus jumping means for moving the focal point of the light beam from the first information face to the second information face by driving the focal point moving means.

Abstract: An optical disc apparatus includes: a converging section for converging a light beam and irradiating a rotating information medium with the converged light beam; a moving section for moving the converging section, thereby moving a converging point of the converged light beam in a direction perpendicular to an information surface of the information medium; a converging state detection section for generating a focus servo signal which represents a converging state of the light beam on the information medium based on reflected light or transmitted light of the light beam from the information medium; a focus servo control section for controlling the moving section based on the focus servo signal, so that the light beam reaches a predetermined converging state on the information medium; and a focus pull-in section for turning ON the control by the focus servo control section, wherein the focus pull-in section turns ON the control by the focus servo control section in a case where the focus pull-in section determin