Canon Kabushiki Kaisha

Kazuhiko Matsuoka

Kazuo Minoura

Masayuki Usui

Akio Aoki

Kenichi Suzuki

Hideki Hosoya

Masahiko Enari

Takeshi Baba

Hiroshi Matsuoka

Satoshi Shikichi

Fumiaki Kawaguchi

Atsushi Someya

Yukuo Nishimura

Kazuyuki Kondo

Kenichi Sasaki

Miho Sugiyama

Osamu Koyama

Nobuaki Date

Noriyuki Nose

Setsuo Minami

Yuko Suga

Takeshi Yamawaki

Tadao Hayashide

Masayuki Suzuki

Seiichiro Satomura

Isao Hakamada

Hideo Yoshikawa

Katuya Yamazaki

Akinori Hasu

Yuko Miyajima

Takesi Baba

Kazuyo Matsumoto

When an image scanner scans an image recorded on an advanced photo system&trade; film, it determines spectral transmittance of a portion of the film, which is not exposed but developed, then sets parameters, such as masking parameters and &ggr; correction parameters, to be used in image signal processes on the basis of the spectral characteristics. Thereafter, the image is read by a CCD and image data is outputted. The film scanner applies the image signal processes to the image data using the parameters set in accordance with the spectral transmittance.

Image read method for performing image signal processes complying with the color of a reference portion of a recording medium, and image read apparatus adopting the method

An image reading apparatus comprises a light source for illuminating an original, an imaging optical system for forming an image of the illuminated original on the focal plane of the system, and a sensor unit arranged in front of the focal plane. At least two infrared cut filters are arranged on the optical path between the light source and the sensor unit. Those infrared cut filters show respective spectral characteristics that are different from each other. The imaging optical system typically comprises a plurality of lenses and the infrared cut filters are arranged on at least two of the respective surfaces of the lenses.

Imaging optical system and original reading apparatus

In an image read apparatus which reads an image from a recording medium, such as a film, and outputs image data, and shading correction data is set. Time elapsed since the shading correction data is set is counted. Before performing main scanning, whether or not the elapsed time is longer than a predetermined period is determined, and if it is, the shading correction data is updated. The read image data is processed with shading correction using the shading correction data which is updated as time elapses.

Image read method and apparatus for optimizing shading conditions

A scanning optical device to be used for an image forming apparatus such as a laser beam printer and a digital copying machine comprises a light source such as a semiconductor laser, an optical deflector such as a rotary polygon mirror, a first optical system for leading the light beam emitted from the light source to the optical deflector, and a second optical system for focussing the light beam deflected by the optical deflector onto a surface to be scanned. The first optical system is adapted to make the light beam strike a deflection surface of the optical deflector with a width greater than that of the deflection surface in the main-scanning direction. The second optical system has an optical element provided on at least an optical surface thereof with an anti-reflection film having a film thickness so adapted as to maximize its light transmittance for the angle of incidence of the most off-axis ray of the light beam deflected by the optical deflector and striking the optical surface.

Scanning optical device and image forming apparatus using the same

In an image reading apparatus provided with a light source for illuminating an original, the light source includes a fluorescent lamp having a tube surface by means of which a part of a beam of light therefrom is condensed on the surface of the original by the optical action thereof, a line sensor for reading image information of the original and an optical device for causing image information of the original illuminated with the beam of light from the light source to be imaged on the line sensor.

Image reading apparatus having a light source including a fluorescent

A magneto-optical information reproducing apparatus includes a device for irradiating a light beam polarized in a predetermined direction onto a recording medium having information magnetically recorded thereon, a device for splitting a reflected or transmitted light beam from the medium, polarization-modulated by a magneto-optical effect in accordance with the information into a first light beam for generating a servo signal and second and third light beams polarized orthogonally for generating a reproduced signal, and a detection device for detecting the three split light beams. The splitting device is arranged such that the three light beams exit in substantially the same direction and the directions of polarization of the second light beam and the third light beam make an angle of 45 degrees with respect to the predetermined direction of polarization of the irradiated light beam.

Magneto-optical information reproducing apparatus that splits a light

An optical head is used in a magnetic field modulation type magnetooptical recording/reproducing apparatus. The optical head includes a device for irradiating a magnetooptical record medium with a light beam, a separating device for separating a reflected light beam from the magnetooptical record medium into two beams to be projected onto a single plane, a single photodetector provided with two two-divided light receiving portions for respectively receiving the two beams, and a single convex lens element for forming images of the two beams as light spots on the single photodetector.

Optical head and optical information reading apparatus

An optical system for an optical information recording/reproduction apparatus, includes a light source, an objective lens for focusing a light beam from the light source on a recording medium, a beam splitter arranged between the light source and the objective lens, a detector for detecting a light beam split by the beam splitter, a galvano mirror arranged between the objective lens and the beam splitter, the galvano mirror having an opening, and a sensor for receiving the light beam from the light source via the opening.

Optical system for optical information recording/reproducing apparatus

An optical head using a semiconductor laser array as a light source comprises a semiconductor laser array in which a plurality of semiconductor lasers are linearly arrayed, a collimator lens, an objective lens and a beam shaping prism system. The beam shaping prism system is arranged between the collimator lens and the objective lens to convert a beam width of a beam emerged from the collimator lens. The junction surfaces of the semiconductor lasers are parallel with an array direction. A plane defined by incident and emerging beams on and from the beam shaping prism system is parallel with or overlapping the array direction of the semiconductor lasers.

Optical head using semiconductor laser array as light source

According to the optical information recording and reproducing apparatus of the present invention, in an optical information recording and reproducing apparatus for recording and/or reproducing information while performing a relative reciprocating movement between a recording and/or reproducing head and an optical information recording medium having information tracks, plural spots including a spot having the function of recording and/or reproducing information formed on said recording medium by said head are arranged so as to be located on the same information track in said recording medium. Further, by switching the functions which at least two spots have during forward movement and during backward movement of said relative movement, it is possible to arrange the spots having roles in accordance with the recording and reproducing apparatus and have them function in a predetermined order. Thus, the present invention has an effect that a stable and correct recording and/or reproduction of information with high speed becomes possible.

Optical information recording and reproducing apparatus with switchable

The information recording method of the present invention comprises steps of recording information on a recording medium by a recording head during forward movement, reading the information recorded during the forward movement in the opposite sequence to the recording sequence during backward movement, and checking if the information has been correctly written or not based on the information read during the backward movement.

Information recording method for reciprocally recording and verifying

An information recording and reproducing apparatus includes a head unit for recording information on and reproducing information from an information recording medium having a plurality of linear tracks arranged in parallel, a device for moving the head unit relative to the recording medium, and a detector for detecting whether the record medium has been loaded into the apparatus in a normal state. The detector includes a photo-detection unit having a light projector for projecting a light beam to the recording medium and a photo-detector for detecting a light beam from the recording medium. The photo-detection unit is arranged such that when the recording medium is inserted in the normal state, the light beam from the light projector illuminates a track of the recording medium and the photo-detector detects high-order diffracted light from the illuminated track.

Information recording and reproducing apparatus including detection of

In an optical information recording medium of the type wherein information is recorded or reproduced when a light beam scans each of a plurality of mutually parallel tracking tracks, an auxiliary track is extended between the adjacent tracking tracks and has at least one portion in parallel with the tracking tracks. In a method of recording or reproducing information by scanning a light beam on each of a plurality of mutually parallel tracking tracks on the recording medium, the recording medium has an auxiliary track which is extended between the adjacent tracking tracks and which has at least one portion in parallel with the tracking tracks and the light beam is kicked in the parallel portion of the auxiliary track.

Optical information recording medium and method for recording

There is disclosed an optical card recorder-reader, in which erroneous signal recording, caused by a low-level light beam when it is stopped at a position for a prolonged period between writing and/or reading operation, either by interruping the irradiation, or by reducing the power of irradiation, or by placing the light beam outside the recording area, when the recording or reading operation is not in progress.

Optical information recording-reproducing apparatus

A biaspherical single lens for an optical information recording-reproducing apparatus comprises a single lens forming an image through a substrate of thickness t and having its first and second surfaces both formed by an aspherical surface and in which when the distance from any point on the aspherical surface to the tangential plane of the vertex of the aspherical surface is X and the distance from said any point to the optic axis is H and the reference radius of curvature of the .nu.th surface is R.sub..nu. and the cone constant of the .nu.th surface is K.sub..nu. and the aspherical coefficient of the .nu.th surface is A.sub..nu.i (i=3, 4, . . . ), the aspherical surface is an aspherical surface expressed by the following equation and satisfies the following conditions (1), (2), (3) and (4): ##EQU1## where F is the focal length of the aspherical single lens, D is the thickness on the optic axis of the aspherical single lens, and N is the refractive index of the aspherical single lens for the wavelength used.

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Yokohama, Japan

Kazuhiko Matsuoka