Abstract: An optical displacement sensor comprises: a light source; a light receiving means adapted to receive light emitted from the light source; and a light diffracting element disposed between the light source and the light receiving means. The light receiving means include a first light receiving element group centrally located, and a second light receiving element group constituted by two separate clusters disposed so as to sandwich the first light receiving element group, and the light diffracting element functions to diffract the light emitted from the light source along one direction of the two-axis directions into a zero-order beam to be received at the first light receiving element group, and higher-order beams received at the second light receiving element group.

Abstract: A spread illuminating apparatus includes at least one light source, a light conductive plate having the at least one light source disposed toward one end surface thereof, and at least one light controlling means disposed between the at least one light source and the light conductive plate. The at least one light controlling means is formed such that a plurality of transparent rectangular solids are stacked one over another vertically and horizontally, and that the transparent rectangular solids are put together by means of adhesive which can transmit light emitted from the at least one light source. The at least one light controlling means has a refractive index profile formed in both directions parallel to and vertical to the light exit surface of the light conductive plate thereby controlling light with respect to the both directions.

Abstract: There is provided an illuminating device which includes: a surface light source including a plurality of light emitting diodes disposed two-dimensionally; a light condensing means comprising a plurality of Fresnel lenses which are disposed corresponding to respective light emitting diodes, and each of which converts a light from each light emitting diode into a substantially collimated light; and a light diffusing means disposed at the stage consequent to the light condensing means, and including a plurality of Fresnel lenses which have a smaller diameter and are arranged in a higher density than the Fresnel lenses of the light condensing means. The illuminating device is adapted to emit a highly bright light with excellence in brightness uniformity, and a light source unit incorporating the illuminating device disposed behind a liquid crystal panel is suitably used in an HUD.

Abstract: A torque measuring device for a rotating body comprises: a rotary section including first and second flanges provided respectively at driving and driven sides, and a hollow cylinder provided between the first and second flanges; light emitting elements provided at an outer circumference of the rotary section, and adapted to emit light based on output from each of torque detectors provided at an inner surface of the hollow cylinder thereby sending an optical signal; a light conductive member to receive the optical signal at a light receiving surface thereof, and to guide the optical signal along its longitudinal directions; and a torque calculator to calculate torque of the rotary section based on the optical signal guided by the light conductive member, wherein the light conductive member has an optical path converting means formed at either the light receiving surface or a surface thereof opposite to the light receiving surface.

Abstract: An illuminating device includes: a light guide bar having a quadrangular prism configuration, formed of a transparent material, and having an optical path converting means provided on two opposite side surfaces thereof and a light source assembly composed of a plurality of point light sources and disposed at one of the two side surfaces of the light guide bar, wherein the point light sources are arrayed along the longitudinal direction of the light guide bar with their light emitting surfaces facing the one side surface of the light guide bar. Lights from the point light sources are introduced into the light guide bar from the one side surface, propagate through the light guide bar, and exit out from one end surface of the light guide bar. Also provided is an image display apparatus which includes the above-described illuminating device, a light modulating means, and a projection optical system.

Abstract: An optical displacement sensor is provided, in which an optical fiber is disposed between a light source and a light receiving means so that light emitted from the light source is conducted therethrough so as to be duly received by the light receiving means whereby a beam diameter can be controlled and a uniform intensity distribution of emitted light can be ensured without providing a pinhole aperture. Also, a six-axis force sensor incorporating such an optical displacement sensor is provided.

Abstract: A torque measuring device for a rotating body includes: a rotary section integrally including a first flange, a second flange, and a hollow cylinder disposed between the first and second flanges; a plurality of torque detectors disposed at the inner circumference of the hollow cylinder; and a light receiving unit. The torque measuring device described above further includes: a light emitting element disposed at the rotational center axis of the rotary section and adapted to emit light based on an output from each of the torque detectors thereby sending an optical signal; a light branching unit to branch the optical signal into a plurality of subsequent signals; and a plurality of passages formed in the rotary section and allowing respective subsequent signals to exit out the rotary section and to be received by the light receiving unit.

Abstract: A spread illuminating apparatus comprises a plurality of LED's as light sources, a light conductive plate, and a light controlling means disposed between the LED's and the light conductive plate. The light controlling means includes a plurality of transparent resin films which have respective different refractive indexes, which are laminated over one another in a direction parallel to a major surface as a light exit surface of the light conductive plate thereby forming a refractive index profile in the direction parallel to the light exit surface of the light conductive plate, and two adjacent ones of which are put together by adhesive that can transmit light emitted from the LED.

Abstract: An optical displacement sensor in an external-force detecting device comprises a light source, an optical sensor, and a light reflecting means. The light source and the optical sensor are disposed at an action section of the device adapted to receive an external force, and the light reflecting means is disposed at a support section of the device adapted to support the action section via elastic spoke sections, and light emitted from the light source is reflected at the light reflecting means and received at the optical sensor whereby displacement of the action section relative to the support section is detected for calculation of an external force applied.

Abstract: An optical pickup apparatus for reading and recording information on recording media includes a semiconductor laser, a collimating lens, a half mirror, a reflecting mirror, and an objective lens. Further included therein are a super-resolution cutoff filter and an aperture control filter, one of which is appropriately selected and set right before the objective lens by a filter switching-over device. When reading the DVD, the super-resolution cutoff filter is set at the optical path, whereas when reading the CD, the aperture control filter is set thereat. The filter switching device is arranged separately from an actuator driving system having the objective lens integrally structured therewith.

Abstract: A torque measuring device for a rotating body includes: a rotary section integrally including a first flange, a second flange, and a hollow cylinder disposed between the first and second flanges; a plurality of torque detectors disposed at the inner circumference of the hollow cylinder; and a light receiving unit. The torque measuring device described above further includes: a light emitting element disposed at the rotational center axis of the rotary section and adapted to emit light based on an output from each of the torque detectors thereby sending an optical signal; a light branching unit to branch the optical signal into a plurality of subsequent signals; and a plurality of passages formed in the rotary section and allowing respective subsequent signals to exit out the rotary section and to be received by the light receiving unit.

Abstract: A liquid crystal element is provided as a polarization plane rotating device between a laser beam source and a beam splitter. Light emitted from the laser beam source passes through the liquid crystal element and the beam splitter, and is converted into parallel light by a collimating lens. The collimated light is incident on a first light-selection device, is reflected at a flat first reflecting surface or a concave second reflecting surface, and is then incident on a super-resolution cut-off filter as a second light-selection device. The light having passed through the second light-selection device is incident on an objective lens, and is converged onto a recording surface. The selection of the reflecting surface of the first light-selection device is determined based on an operation mode of the liquid crystal element.

Abstract: A laser beam emitted from a laser diode and having a wavelength of 780 nm is S-polarized. A polarization plane rotating means (?/4 phase plate) is disposed between a super-resolution cut-off filter comprising a polarizing filter film and an objective lens. When reading on DVD, the objective lens, the polarization plane rotating means and the super-resolution cut-off filter in combination are set to the optical path. The S-polarized laser beam is focused to a micro spot diameter by super-resolution effects by the super-resolution cut-off filter together with the objective lens. Also, the S-polarized laser beam reflected at a disk and traveling backward along the incoming optical path is converted into a P-polarized laser beam while passing backward through the polarization plane rotating means. The P-polarized laser beam passes through the super-resolution cut-off filter without loss is received by a photo-detector.

Abstract: An external force detecting device comprises a hollow-cylindrical support section, an action section disposed centrally inside the support section, and an optical displacement sensor which includes, at the action section on its center axis: a light source to emit a light beam in a direction along the center axis of the action section; a light branching member to branch the light beam into three light beams to progress respectively in three directions oriented at an equi-angular distance; and a light reflecting member to reflect the three light beams in a direction parallel to a plane perpendicular to the center axis, and which also includes, at the support section, three light receiving elements arranged in a rotation-symmetric manner at a 120 degree interval with their light receiving faces looking toward the center axis of the action section so as to receive respectively the three light beams reflected.

Abstract: A torque measuring device for a rotating body comprises: a rotary section including first and second flanges provided respectively at driving and driven sides, and a hollow cylinder provided between the first and second flanges; light emitting elements provided at an outer circumference of the rotary section, and adapted to emit light based on output from each of torque detectors provided at an inner surface of the hollow cylinder thereby sending an optical signal; a light conductive member to receive the optical signal at a light receiving surface thereof, and to guide the optical signal along its longitudinal directions; and a torque calculator to calculate torque of the rotary section based on the optical signal guided by the light conductive member, wherein the light conductive member has an optical path converting means formed at either the light receiving surface or a surface thereof opposite to the light receiving surface.

Abstract: An information reading and recording apparatus includes a super-resolution cut-off filter having an annular metal reflection film at its center portion and disposed immediately before one of two objective lenses with a higher NA. When reading DVD, the one objective lens with a higher NA with the super-resolution cut-off filter disposed therebefore is positioned at the optical path. When reading CD, the other objective lens with a lower NA is positioned at the optical path. The laser beam reflected by a disk follows backward the incoming optical path to pass through a half mirror, and is received by a photo-detector to be converted into an electrical signal.

Abstract: In a six-axis force sensor, each optical displacement sensor comprises an optical module to emit a light and a reflecting member to reflect the light back to the optical module, such that the optical axis of the light from the optical module is aligned to the axial direction of the six-axis force sensor, rather than to the radial direction. Consequently, the six-axis force sensor can be downsized in the radial direction.

Abstract: An optical information reading apparatus includes a semiconductor laser, a beam splitter, a collimating lens, a super-resolution cut-off filter, an objective lens having a high numerical aperture, and a photodetector. The super-resolution cut-off filter is disposed immediately in front of the incident side of the objective lens. The photodetector is a well-known eight-division photodetector with a signal processing circuit, reads recorded information and also outputs tracking and focusing control signals to a control circuit. The laser beam is separated into a 0-th order laser beam and ± primary laser beams, which are made incident on the objective lens, pass therethrough, and are made incident on the recording surface of a disk. The 0-th order laser beam is used to read information and to control focussing while the ± primary laser beams are used to control tracking.

Abstract: An optical displacement sensor is provided, in which an optical fiber is disposed between a light source and a light receiving means so that light emitted from the light source is conducted therethrough so as to be duly received by the light receiving means whereby a beam diameter can be controlled and a uniform intensity distribution of emitted light can be ensured without providing a pinhole aperture. Also, a six-axis force sensor incorporating such an optical displacement sensor is provided.

Abstract: An optical displacement sensor comprises: a light source; a light receiving means adapted to receive light emitted from the light source; and a light diffracting element disposed between the light source and the light receiving means. The light receiving means include a first light receiving element group centrally located, and a second light receiving element group constituted by two separate clusters disposed so as to sandwich the first light receiving element group, and the light diffracting element functions to diffract the light emitted from the light source along one direction of the two-axis directions into a zero-order beam to be received at the first light receiving element group, and higher-order beams received at the second light receiving element group.