Abstract: A hologram-reproducing method is adapted to obtain a reproduced image by irradiating a hologram-recording material with a reference-light beam so that a reproduction signal-light beam is generated and picking up an image of the reproduction signal-light beam. The hologram-reproducing method includes the steps of generating a plurality of reproduced images by irradiating the hologram-recording material with a plurality of reference-light beams and generating a single reproduced image by performing image processing for the plurality of reproduced images.

Abstract: A hologram recording and reproducing apparatus includes a movable galvanomirror, a mirror controller and a reproduction unit. The galvanomirror guides a reference beam toward a hologram recording medium and changes the incident angle of the reference beam. The mirror controller causes the galvanomirror to move for adjusting the incident angle to a predetermined angle for hologram recording. In reproducing the recorded information, the mirror controller causes the galvanomirror to move, so that the incident angle continuously changes within a predetermined range including the predetermined angle. The reproduction unit receives a detection signal from an optical detector while the incident angle changes continuously. The detection signal corresponds to the intensity of a reflected beam from the hologram recording medium. The reproduction unit reproduces the recorded information, based on the detection signal, when the intensity of the reflected beam is over a predetermined level or reaches the maximum.

Abstract: Microstructured articles, such as a retroreflective articles, having a plurality of (e.g. cube-corner) microstructured elements and a seal film layer adhered to portions of the cube-corner elements and/or portions of a (e.g. flexible) body layer. The seal film is a thermoplastic polymeric material comprising reaction products of alkylene in an amount of at least about 50% and reaction products of at least one non-acidic polar monomer.

Abstract: A multi-function lens module includes a cylindrical first part and a second part. The first part includes a peripheral side wall and defines an inner space; and the first part has a central axis. The second part is received in the inner space of the first part. The first part is capable of rotating relative to the second part. The first part defines at lease two pairs of openings. Each pair of openings is symmetric about the central axis. A first pair of the openings is configured for accommodating first optical elements. A second pair of the openings is configured for accommodating second optical elements. The second part defines a first through hole. The first through hole receives a third optical element.

Abstract: A grating includes an absorptive substrate and a plurality of reflective lines on the absorptive substrate. Each reflective line is formed by a plurality of reflective areas. The reflective areas can be arranged in a regular pattern. The reflective areas are between 70 nm and 120 nm in diameter. The reflective areas can be circular. The reflective areas can have a random height distribution.

Abstract: A method and apparatus for performing reproduction position servo-control without reducing the recording capacity of a holographic recording medium. Upon the reproduction of a holographic recording medium 18, part of a reproduction beam serving as a servo beam is projected onto a recording layer 18A of the holographic recording medium 18 from the side opposite to the side of the reproduction beam (a reference beam) along the same optical axis as that of the reproduction beam, and the diffraction beam thereof is detected by a photodetector 26C through a polarizing beam splitter 26B.

Abstract: A sequential illumination system for a visual display unit has a light source emitting a polychromatic light beam towards the visual display unit within a wavelength range having at least three primary colors, and a color wheel provided with at least three transmissive or reflective segments for transmitting the light beam along an optical path in such a way that they successively cut the direction of propagation of the beam. The colour segments are distributed on the wheel in such an order that the differences of energies perceived by the visual organ of a standard observer (visual stimuli), are as equivalent as possible during the intersegment transitions, when the segments pass along the optical path of the beam. The illumination system can be used for movie overhead projection devices.

Abstract: A wavelength selective optical switch particularly usable as a programmable N×M optical switch in a multi-wavelength communication system. The switch uses a grating that separates multi-channel optical signals into a plurality of optical channels, and combines a plurality of optical channels into multi-channel optical signals. Programmable mirrors switch each optical channel to any of a plurality of fibers coupled to the switch.