Ricoh Company, Ltd.

Nec Corporation

Laserfront Technologies, Inc.

Nicoh Company, Ltd.

Yukio Ogura

Toshio Inada

Hironobu Mifune

Aki Ueda

Yoshinori Ohta

Shingo Murakami

Yukio Morishige

Junichi Kitabayashi

Hideyuki Moribe

Susumu Tsujikawa

Hisao Ishii

Mitsuhisa Fukuda

Katsunori Nagamatsu

Katsuhiko Nakatani

Yoshiaki Aida

Tsuyoshi Yamane

An optical packet header identifier having a simplified configuration and being superior in reliability, stability, and economical efficiency, an optical router incorporating the identifier therein, and a routing method using the optical router are provided. The optical packet header identifier includes an optical waveguide, optical focusing elements, and a photo receiver. Tilted gratings for diffracting an incident optical beam and emitting the beams as diffracted optical beams to the outside of the waveguide are formed within the optical waveguide. The tilted gratings are not formed uniformly in a longitudinal direction of a core of the optical waveguide, but are arranged at intervals. The length of a portion containing a set of gratings and the length of a portion containing no gratings can be defined in increments of length 'L'. 'L' equals to the spatial length which 1 bit in an optical signal occupies.

Optical packet header identifier, optical router incorporating the same therein, and optical routing method using the router

The present focusing method is used in a focus detecting apparatus comprising an objective lens, means for entering a luminous flux for focus detection into a target object from a position inconsistent with an optical axis of the objective lens through at least the objective lens, a condenser lens for converging the luminous flux after it is reflected by the target object and again passes through the objective lens, two two-division sensors disposed with the same optical inclination in front of and behind a position where the reflected luminous flux is converged by the condenser lens when a focus of the objective lens is adjusted to the surface of the target object, and a signal processing circuit for performing operational processing of signals from the two two-division sensors. The focus detecting apparatus detects whether the focus of the objective lens is adjusted to the surface of the target object. When focusing is performed with this apparatus, the target object is moved while the focus position is followed after the detection of the focus position, focus detection is performed many times and the detected signal values are averaged, and the resultant average value is used to drive the objective lens. This series of operations is repeated, and then the focus position is fixed.

Focusing method

Laser scanning optics for scanning a laser beam issuing from a laser in the main scanning direction while repeatedly steering it in the subscanning direction is disclosed. The laser scanning optics includes focusing optics for focusing the laser beam, a first deflector for steering the laser beam in the subscanning direction, and a second deflector for steering the laser beam in the main scanning direction. The focusing optics causes the laser beam to form an elliptical beam spot, which is elongate in the main scanning direction, in a scanning plane. The first deflector is driven such that the laser beam is scanned at a higher speed in the subscanning direction than in the main scanning direction. The first deflector is so controlled, based on a value input beforehand or data measured beforehand, as to correct the distortion of linearity in the main scanning direction by subscanning.

Laser scanning optics and laser scanning method using the same

A device and method for inspecting a test piece with a laser beam in which the laser beam is divided into plural beams, and each of the plural beams has an identification marker, such as a particular polarity or intensity. Each of the marked beams, scans a different portion of the test piece to reduce the time needed to inspect the test piece.

Method and apparatus for inspecting high-precision patterns

In a single panel color projection LCD, white light emitted from a light source is optically processed by an optical processing unit so as to convert three primary color beams obtained from the white light into predetermined polarized beams. All of the predetermined polarized beams may be P-polarized beams or S-polarized beams. Thereafter, the optical processing unit irradiates only the predetermined polarized beams onto the liquid crystal panel without an optical power loss. A color image which is given by the liquid crystal panel is projected onto a screen to be displayed in an enlarged form.

Single panel color projection LCD having a plurality of reflectors

A focal point detecting apparatus for an objective lens is disclosed for inspecting whether or not the focal point of the objective lens used in an electron microscope, an optical inspecting apparatus, a laser processing apparatus, etc. is positioned on a surface of a target object. The focal point detecting apparatus comprises for entering an optical beam for detecting a focal point from a position deviant from an optical axis of an objective lens to a surface of a target object to be inspected through at least the objective lens; and two two-split sensors on which the optical beam reflected from the surface of the target object so as to pass again through the objective lens is converged by at least a condenser lens. The two two-split sensors are arranged at the same optical inclination in front of and behind the position on which the reflected optical beam is converged by the condenser lens when the focal point of the objective lens is positioned on the surface of the target object.

Detection of focal point of objective lens by means of a two-split sensor

In an optical illumination instrument for use in photolithographic process of manufacturing semiconductor devices, a reflection type homogenizer is composed of an array of paraboloid mirrors of a same size arranged on a same plane.

Optical illumination instrument

A parallel image processing apparatus includes (1) a light diffusing layer, (2) a photoelectric conversion layer which receives diffused light from the diffusion layer, and (3) an edge detection layer which receives signals from conversion elements in the conversion layer, and generates edge information which defines the edge of object(s) imaged on the light diffusing layer. The conversion layer includes pairs of conversion elements, the pairs having a center element and a peripheral element surrounding it. Signals from one or more center elements are summed, the sum being differentially amplified with a sum of signals from one or more peripheral elements to arrive at an edge signal. Edge signals may be used to differentiate among characters, pictures or photographs, and a blank images.

Parallel image processing apparatus using edge detection layer

A parallel optical information processing system includes an information inputting part which produces a coherent optical beam spatially modulated by input image information. A rewritable hologram memory carries a plurality of stored images as holograms so that the holograms are overlapped with each other, the rewritable hologram memory being written with image information when illuminated by a recording optical beam. An image reproducing part is supplied with the input image information, and produces reproduced image information from the rewritable hologram memory. A hologram synthesizing part synthesizes a synthetic hologram in response to the reproduced image information. A hologram recording part records the synthetic hologram in the rewritable hologram memory through the recording optical beam.

Parallel optical information processing system

A parallel image processing system comprises an image detection array of photodector elements, edge detection circuit including a number of edge detection elements for producing an output signal indicating detection of edge of the input image, and movement detection circuit including a number of movement detection elements each being supplied with output signals from a first group of the edge detection elements along a first signal path as an excitement signal and further from a second group of the edge detection elements along a second signal path as an inhibitory signal, for producing a movement detection signal indicating movement of the input image on the basis of comparison of the excitement signal and the inhibitory signal.

Parallel image processing system

An optical processing system comprises first light source, a spatial modulator for modulating optical beam passing therethrough, an image input part for writing the input image on the modulator by means of an incoherent optical beam, an optical Fourier transform device, an optical memory for storing a plurality of image informations in a form of Fourier transform hologram comprising a medium which allows erasing and rewriting of information by optical beam, an image detection/light source device supplied with a plurality of optical beams for producing another optical beam in correspondence to one of the optical beams which has the maximum intensity along a path of that optical beam in a reversed direction, a second light source for irradiating the optical memory by another optical beam for writing a new information, an image output device provided in an optical path of the output beam, and a controller connected to the image input device, first light source and second light source for controlling energization thereof, in which the controller is further connected to the modulating means and optical memory means for clearing informations written thereon.

Optical parallel processor

In laser beam scanning by a rotating polygonal mirror, a hologram scanner, etc., a cylindrical lens having a refractive power in a sub-scanning direction is introduced to place the beam deflecting surface and the scanning surface in a geometrical-optically conjugative relation, in order to prevent occurrence of a deviation in position of scanning line due to a deviation of the beam deflecting surface. However, in a Gauss beam such as a laser beam, a beam waist is not produced in a geometrical-optical conjugate point. This relation is utilized to select optical elements whereby apparatus may be miniaturized and the size of the beam spot may be adjusted.

Laser beam scanning apparatus

A self-focusing fiber array comprises three rows of self-focusing fibers, which are most closely packed and each of the self-focusing fibers substantially satisfies an equation of ##EQU1## where n.sub.o is the refractive index at the center of the cross section of each of the self-focusing fibers and n(r) is the refractive index at a distance r from the center of the cross section and a is a positive constant, and each of the self-focusing fibers is equal in the length under a condition of ##EQU2## and each end surface of the self-focusing fibers is in the same plane.

Self-focusing fiber array

A curved reflector is disposed behind an elongated lamp for reflecting light from the lamp onto a document carrier in the form of a narrow elongated beam. The carrier is movable perpendicular to the beam for scanning a document placed on the carrier. One or more orifices are formed through the back of the reflector and a blower creates an air flow through the orifice and around the lamp for cooling the same.

Growing community of inventors

Tokyo, Japan

Yukio Ogura