Abstract: A distance measurement device includes: a mirror disposed so as to be tilted relative to a rotation center axis; a drive unit configured to rotate the mirror about the rotation center axis; a photodetector configured to detect reflected light, of laser light, reflected in a distance measurement region; and a condensing lens disposed on the rotation center axis and configured to condense the reflected light reflected by the mirror, on the photodetector. The mirror has a shape elongated in one direction and is disposed such that a short axis thereof is tilted relative to the rotation center axis in a direction parallel to a plane including the rotation center axis. A width in a short-axis direction of the mirror is smaller than a width of a lens portion of the condensing lens as viewed in a direction parallel to the rotation center axis.

Abstract: There is provided a distance measurement device that can appropriately detect a distance to an object regardless of the distance. The distance measurement device includes a laser light source, a photodetector, and a controller. The controller performs a long-distance routine that detects timing for receiving light when an object is at a long distance, and a short-distance routine that detects the timing for receiving light when the object is at a short distance, based on a detection signal output from the photodetector during one distance measurement operation. The controller then selects one of a detection result of the timing for receiving light by the long-distance routine and a detection result of the timing for receiving light by the short-distance routine, and calculates the distance to the object irradiated with projection light based on the selected detection result.

Abstract: A distance measurement device for measuring a distance to an object that exists in a distance measurement region includes: a light source configured to emit laser light; a lens configured to converge the laser light emitted from the light source, into substantially parallel light; a tubular light blocking member disposed on an optical path of the laser light emitted from the light source and surrounding the optical path; a photodetector configured to detect reflected light, of the laser light, reflected at the distance measurement region; and a condensing lens configured to condense the reflected light passing through the outside of the light blocking member, onto the photodetector.

Abstract: A distance measuring device applies laser light to a distance measurement region and measures a distance to an object that exists in the distance measurement region. The distance measuring device includes: a condensing lens configured to condense reflected light, of the laser light, reflected by the object; a tubular adjustment member disposed at a stage subsequent to the condensing lens and having a first reflecting surface and a second reflecting surface formed on an inner surface on which the reflected light condensed by the condensing lens is incident, a tilt angle of the second reflecting surface relative to an optical axis of the condensing lens being different from that of the first reflecting surface; and a photodetector configured to receive the reflected light that has traveled through the adjustment member.

Abstract: A distance measurement device includes: a mirror disposed so as to be tilted relative to a rotation center axis; a drive unit configured to rotate the mirror about the rotation center axis; a photodetector configured to detect reflected light, of laser light, reflected in a distance measurement region; and a condensing lens disposed on the rotation center axis and configured to condense the reflected light reflected by the mirror, on the photodetector. The mirror has a shape elongated in one direction and is disposed such that a short axis thereof is tilted relative to the rotation center axis in a direction parallel to a plane including the rotation center axis. A width in a short-axis direction of the mirror is smaller than a width of a lens portion of the condensing lens as viewed in a direction parallel to the rotation center axis.

Abstract: There is provided a distance measurement device that can appropriately detect a distance to an object regardless of the distance. The distance measurement device includes a laser light source, a photodetector, and a controller. The controller performs a long-distance routine that detects timing for receiving light when an object is at a long distance, and a short-distance routine that detects the timing for receiving light when the object is at a short distance, based on a detection signal output from the photodetector during one distance measurement operation. The controller then selects one of a detection result of the timing for receiving light by the long-distance routine and a detection result of the timing for receiving light by the short-distance routine, and calculates the distance to the object irradiated with projection light based on the selected detection result.

Abstract: A first recording layer for recording information of an optical disk and a second recording layer of the optical disk on which a visible image can be recorded are disposed at an interval of 0.5 mm or more. Thus, even when a high power laser is used on one of the layers, data on the other layer will not be destroyed.

Abstract: An optical disk apparatus that performs focus control and tracking control, the focus control focusing an objective lens on an optical disk, and the tracking control making the objective lens track a partial area on the optical disk. The optical disk apparatus has a light-blocking element and a light detector. The light-blocking element is disposed on a first light path on which light reflected by the optical disk travels, and blocks a part of the reflected light. The light detector detects, for the focus control, the reflected light which passes the light-blocking element. The light-blocking element has a predetermined area for blocking the reflected light, the predetermined area extending along a direction optically corresponding to the tracking direction in which the objective lens tracks, for the tracking control, the partial area on the optical disk.

Abstract: An actuator device, an optical disk device and an information playback device comprising: an objective lens for focusing a light on a recording and/or playback face of a recording medium; a lens holder for holding the objective lens; a suspension for elastically supporting the lens holder; and an actuator base for supporting the suspension. The lens holder has a portion on the opposite side in the optical axis of the objective lens with respect to the actuator base.

Abstract: A first recording layer for recording information of an optical disk and a second recording layer of the optical disk on which a visible image can be recorded are disposed at an interval of 0.5 mm or more. Thus, even when a high power laser is used on one of the layers, data on the other layer will not be destroyed.

Abstract: An actuator device, an optical disk device and an information playback device comprising: an objective lens for focusing a light on a recording and/or playback face of a recording medium; a lens holder for holding the objective lens; a suspension for elastically supporting the lens holder; and an actuator base for supporting the suspension. The lens holder has a portion on the opposite side in the optical axis of the objective lens with respect to the actuator base.

Abstract: In an optical pickup, an optical guide member is provided in an optical path of light from a light source, and has a plurality of inclined surfaces inclined with respect to a light beam emitted from the light source. A light-receiving element is provided for receiving light and for converting the received light into an electrical signal. The optical guide member and the light-receiving element are contained in a packaging member. The light beam from the light source is reflected by the plurality of inclined surfaces of the optical guide member, and then are directed to a recording medium. The reflected light from the recording medium is directed to the light-receiving element. At least one of dry air and inert gas such as nitrogen gas is charged in the interior of the packaging member at a pressure of 0.5 atm to 1.5 atm, thereby preventing the optical characteristics from being degraded.

Abstract: An optical information storage medium includes a multilayer structure formed on a substrate. The multilayer structure is formed by a sputtering process in a discharge gas and includes at least a first dielectric layer, a recording layer which shows reversible phase change between an amorphous phase and a crystal phase, and a second dielectric layer. The multilayer structure contains sufficiently small amount of the discharge gas so that a limited amount or less of voids of the discharge gas generates in the recording layer during repeated overwrite operations.

Abstract: An optical information recording medium includes: a substrate including a groove having a concave shape and a land having a convex shape adjacent to the groove; and a recording layer on the substrate, wherein the recording layer consists of a material which changes between a first state and a second state whose optical property is different from that of the first state, a first portion of the optical information recording medium including a portion in the first state of the recording layer having a first reflectance, and a second portion of the optical information recording medium including a region in the second state of the recording layer having a second reflectance which is different from the first reflectance, whereby information is recorded onto the groove and the land, and wherein a ratio of the first reflectance to the second reflectance, a phase of reflected light from the first portion and a phase of reflected light from the second portion are set such that at least one of an amplitude and a carrier

Abstract: A compression-type semiconductor device comprises a silicon substrate in which crystal orientation between main faces opposite to each other is not larger than <1,0,0> .+-.27.5.degree.; cathode and gate electrodes formed on one of the main faces of the silicon substrate; an anode electrode formed on the other of the main faces of the silicon substrate; a cathode thermal compensation plate for the cathode and gate electrodes; and an anode thermal compensation plate for the anode electrode.

Abstract: In forming steps of a recording layer or a dielectric layer of a phase change type optical disk by sputtering, a discharge gas which includes at least one of Kr gas and Xe gas is used. Alternatively, at least one of Ar gas and N.sub.2 gas may be further added to the discharge gas. Forming the recording layer or the dielectric layer of the phase change type optical disk in these discharge gases enables preventing of the introduction of the discharge gas into each layer during the forming steps. As a result, the void generation and growth in the recording layer is suppressed. Consequently, the deterioration of the cycle life characteristics due to repeated overwrite operations can be restrained. Therefore, high reliability and long life of the phase change type optical disk is attained.