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 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 plate body 2, multiple hologram layers 3 are provided in the thickness direction of the plate body 2, and at least one of the multiple hologram layers 3 is formed of spirally continuous hologram bands 4. Erasure areas 4A and 4B and non-erasure areas 4C and 4D of the hologram band 4 are provided in the length direction of the hologram band 4. Non-erasure areas 4E and 4F of the hologram band 4 are formed on both sides in the direction orthogonal to the length direction of the hologram band 4 in the erasure areas 4A and 4B.

Abstract: A plate body 2, multiple hologram layers 3 are provided in the thickness direction of the plate body 2, and at least one of the multiple hologram layers 3 is formed of spirally continuous hologram bands 4. Erasure areas 4A and 4B and non-erasure areas 4C and 4D of the hologram band 4 are provided in the length direction of the hologram band 4. Non-erasure areas 4E and 4F of the hologram band 4 are formed on both sides in the direction orthogonal to the length direction of the hologram band 4 in the erasure areas 4A and 4B.

Abstract: To accomplish the object, the invention provides a record medium including a plate body 2; multiple hologram layers 3 formed in the thickness direction of the plate body 2; and hologram bands 4 formed in at least one of the multiple hologram layers 3. The hologram band 4 is formed with erasure areas 4A and 4B of the hologram band 4 with no hologram band 4 in the direction orthogonal to the length direction of the hologram band 4.