Canon Kabushiki Kaisha

Masamichi Tateoka

Kazuo Minoura

Setsuo Minami

Tsutomu Toyono

Toshinori Ando

Takao Tsuji

Hideaki Yano

Hiroshi Hara

Osamu Koyama

Naoto Kawamura

Hisashi Fukushima

Yoshihiro Takada

Jun Makino

Takehiko Nakai

Yoshikazu Yokomizo

Kazuya Matsumoto

Mitsuru Kurata

Mitsuhiro Tokuhara

Sadatoshi Takahashi

Kazuyuki Kondo

Junichi Asano

Motomu Fukasawa

Yukihiko Ogata

Hiraku Sonobe

Akiyoshi Torigai

Teruo Morikawa

Toshiaki Asano

Makoto Shihou

Koichi Ida

An optical scanning apparatus comprises a light source provided with a plurality of light emitting portions different in emission wavelength on a single stem, a deflector for deflecting a plurality of beams from the light source an optical system for converging the plurality of beams deflected by the deflector, and a wavelength separation device for separating the plurality of beams from the optical system from each other. The optical scanning apparatus may be applicable to a laser beam printer by combining it with a photosensitive member to which the plurality of beams separated by the wavelength separation device are guided.

Optical scanning apparatus

A plural-beam scanning optical apparatus comprises a light source having a plurality of light emitting portions, a first optical system for converting a plurality of divergent light beams from the light source into parallel light beams, a light deflector for deflecting the plurality of light beams from the first optical system, a stop disposed between the first optical system and the light deflector, and a second optical system for condensing the plurality of light beams deflected by the light deflector on a scanned surface. The plurality of light emitting portions are arranged in a direction oblique with respect to the main scanning direction of the light beams on the scanned surface. The apparatus satisfies the following condition:

Plural-beam scanning optical apparatus

An image recording apparatus comprises a beam generating unit for generating a light beam modulated in accordance with input image signal, a beam deflecting unit for scanning a recording medium using the light beam generated by the beam generating unit, the beam deflecting unit comprising a rotating polygon mirror having a plurality of reflecting surfaces. The apparatus can be operated in a mode for forming an image using all the reflecting surfaces of the rotating polygon mirror and in a mode for forming an image using predetermined reflecting surfaces of a plurality of reflecting surfaces of the rotating polygon mirror. The apparatus thus permits the dot density to be changed to a plurality of values with a simple structure so that image information can be recorded with high definition on the surface of a recording medium.

Image recording apparatus

A scanning optical apparatus has a light source for emitting a light beam, and a deflector such as rotatable polygonal mirror having a plurality of mirror surfaces for deflecting the light beam emitted from the light source. Each mirror surface of the rotatable polygonal mirror has a pair of reflecting surfaces inclined toward the center axis of rotation of the polygonal mirror and orthogonal to each other. A fixed reflecting mirror is arranged in opposed relationship with one of the pair of reflecting surfaces so that the light beam deflected by the deflector is reflected to be returned to the deflector again.

Scanning optical apparatus

A projecting apparatus comprises support device for supporting an original, a projection optical system for forming the image of the original, an optical element disposed on the image side of the projection optical system to cause a principal light ray having entered from the original through the projection optical system to travel in parallelism to the optic axis of the projection optical system, and control device for varying the imaging magnification of the original by the projection optical system with the spacing between the exit pupil of the projection optical system and the optical element being kept constant.

Projecting apparatus

The present invention relates to a scanning optical system and a scanning optical apparatus in which the pivot axis and the mirror surface of the deflector are inclined to have a predetermined relationship so as to obtain practical planeness of a surface to be scanned. A scanning optical system according to the present inhvention comprises a light source, lens for converging a light beam from the light source and a deflector for deflecting the light beam in a predetermined direction. In the optical scanning system according to the present invention, the maximum deflection angle of the deflector, a relationship between a radius of curvature of the deflection/reflection surface of the deflector and a distance between an object point of a light beam incident on the deflection/reflection surface of the deflector and the deflection/reflection surface for reflecting a central ray of the incident light beam, are determined to satisfy with a predetermined condition. And further, a relationship between an angle defined by a predetermined pivot axis of the deflector and the deflection/reflection surface of the deflector and an incident angle of the light beam from the light source to the deflection/reflection surface of the deflector within a plane including the predetermined axis and perpendicular to the deflection plane when the light beam emerging from the deflector is present within a single plane, is determined to satisfy with a predetermined condition.

Scanning optical system

An optical scanning apparatus in which a plurality of scanning light beams are deflected by a light deflector and the deflected light beams impinge onto a spherical lens having an f-.theta. characteristic at inclinations with respect to the optical axis of the lens so as to be focused on a scanning object. The apparatus is arranged to meet the following condition: ##EQU1## where, f represents the focal distance of the spherical lens (mm), .omega. represents the effective scanning rotation angle of the light deflector (deg), .DELTA.(.omega.) represents the amount of curve of the scanning line caused by the light deflecting element in the subscanning direction (mm), .rho. represents the resolution of the scan on the scanning object (lines/mm), .theta. represents the angle of inclination of any one of the light beams with respect to the optical axis of the lens within a plane which contains the optical axis of the lens and which is perpendicular to the scanning axis (deg), L represents the distance between the first reflection surface of the light deflector and the principal plane of the lens adjacent the scanning object along the optical axis (mm), and h represents the height of incidence of the any one of the light beams to the lens (mm).

In an optical pickup apparatus comprising a light source for applying a light beam to an optical memory medium, a beam splitter disposed in the optical path from the light source to the medium to separate the reflected beam from the medium from the beam from the light source, and a photodetector for detecting the separated reflected beam, having a surface opposed to that surface of the beam splitter which faces the photodetector is formed so as to form an angle different from the perpendicular with respect to the optic axis of the separated reflected beam.

Optical pickup apparatus

An optical information processing apparatus comprising record/reproduction devices for irradiating a focused light beam onto a track on a record medium to record or reproduce information tracking control devices for precisely directing the irradiated light beam to the track split devices for splitting at least a portion of a reflected or transmitted light beam of the irradiated light beam from the record medium into two light beams first screen devices for screening a center area of one of the split light beams across a width of the track second screen devices for screening a peripheral area of the other of the split light beams across the width of the track and detection devices for comparing light intensities of the two light beams transmitted without being screened by said first and second screen devices to detect a focusing state of the irradiated light beam to the record medium.

Optical information processing apparatus for light beam focus detection

The scanning optical system of this invention has a light source, a first focussing optical system linearly focussing a light beam coming from the light source, a deflector having its deflecting-reflection surface in the vicinity of the focussing image, and a second focussing optical system for focussing the light beam deflected by the deflector on a medium to be scanned. The second focussing optical system has a spherical single lens having negative refractive power, a spherical single lens having positive refractive power and a single lens having a toric surface. By this arrangement, a focussing spot having a small diameter in the main scanning direction and having a well compensated curvature of field and distortion can be formed on the medium to be scanned.

An apparatus for reading the image of an original comprises a imaging device for forming the image of the original, an image pickup device provided at a position where the image is formed by the imaging device, the image pickup device photoelectrically converting the image of the original into an electrical signal, and a device for separating the light beam from the original disposed between the original and the image pickup device, a plurality of images of the original being formed on the image pickup device by the separating device.

Reading apparatus

There is disclosed a light source device in which first and second semiconductor lasers are disposed relative to a polarizing beam splitter so that the laser beam from the first is transmitted while that from the second is reflected by the beam splitter, and that the major and minor directions in the cross section of the first beam are respectively co-ordinated with those of the second beam. An optical element capable of rotating the plane of polarization of an incident beam by approximately 90.degree. is disposed between one of the semiconductor lasers and the polarizing beam splitter. In this manner the beams from the seconductor lasers can be guided, with respectively co-ordinated major and minor directions in the beam cross section, in the same direction without any decrease in the quantity of light.

Light source device for close spacing of two light beams

An optical information processing apparatus is provided with a unit for recording and reproducing information by projecting a main beam onto an information track on a recording medium, a unit for projecting at least two or more than two subsidiary light beams onto the information track to form light spots at different position in the transversal direction of the information track by the respective light beams and a unit for detecting the subsidiary beams reflected by the recording medium to derive a tracking signal for guiding the main beams correctly on the information track, and those light spots are larger in size in the longitudinal direction of the information track than in the transversal direction thereof.

Optical information processing apparatus

This specification discloses a projection lens for projecting an original onto the surface of a sensor and for use in a facsimile apparatus or a digital copying apparatus. The projection lens enables the image of the original to be projected onto the sensor at different projection magnifications with the length of the optical path between the surface of the original and the sensor kept constant. The projection lens comprises, in succession from the object side, a first lens group comprising a negative meniscus lens having its convex surface facing the object side, and a positive meniscus lens having its convex surface facing the object side, the first lens group as a whole having a negative refractive power, and a second lens group having three positive lenses and a negative lens, the second lens group as a whole having a positive refractive power. The first lens group is stationary and the second lens group is movable, whereby the image of the original is projected onto the surface of the sensor at different projection magnifications with the object-image distance being kept constant.

Projection lens

This specification discloses a plural-beam scanning apparatus in which the directions of light emission of light-emitting portions such as semiconductor lasers or light-emitting diodes are determined so that the central rays of light beams emitted from the light-emitting portions are emitted as if they originate from or pass through substantially the same point as viewed from a direction perpendicular to the deflection scan plane and which has a deflector for deflecting a plurality of light beams from the light source unit at one time and optical means for making said same point and a point near the deflecting-reflecting surface of the deflector optically conjugate.

Growing community of inventors

Yokohama, Japan

Masamichi Tateoka