Ricoh Company, Ltd.

Taku Amada

Seizo Suzuki

Tomohiro Nakajima

Kazuyuki Shimada

Naoki Miyatake

Satoru Itoh

Yoshinori Hayashi

Mitsuo Suzuki

Akihisa Itabashi

Takeshi Ueda

Nobuaki Kubo

Akira Kojima

Ikuko Yamashiro

Toshihiro Suzuki

Tadashi Nakamura

Koji Masuda

Hiromichi Atsuumi

Koichi Kudo

Hibiki Tatsuno

Yasuhiro Nihei

Toshiaki Tokita

Yukio Itami

Hiroyuki Suhara

Atsushi Takaura

Kenichi Shimizu

Asato Tamura

Atsuhiko Ogawa

Shingo Tachikawa

An objective is to achieve a positional change measurement device which measures positional change of a dynamic measured surface by using speckle patterns while easily reducing influence of fluctuations in a measurement environment temperature. Provided is a positional change measurement device including: a light source; an illuminating optical system configured to guide light from the light source to a measured surface; an imaging optical system; an image pickup device configured to acquire a speckle pattern by receiving reflection light from the measured surface via the imaging optical system; and detected-length compensation means for compensating for fluctuations in a detected length caused by temperature fluctuations. Positional change of the measured surface is measured based on a result of cross-correlation computation performed on multiple speckle patterns acquired at predetermined time intervals.

Positional change measurement device, positional change measurement method, and image forming apparatus

An optical scanning device includes: a light source device that emits five light beams corresponding to four basic colors and a single specific color; and five scanning optical systems corresponding the five light beams. One light beam in a first waveband among the light beams corresponding to the four basic colors enters one scanning optical system of the five scanning optical systems. The one scanning optical system includes a dichroic mirror that transmits a light beam in a second waveband different from the first waveband. An angle &#x3b8;b formed between a normal to the incidence plane of the dichroic mirror and orthogonal projection to an assumed plane orthogonal to the main scanning corresponding direction of the incident path of the light beam to the incidence plane of the dichroic mirror is set at an angle of 0&#xb0; or more and an angle of 45&#xb0; or less.

Optical scanning device and image forming apparatus in which a plurality of scanning optical systems except one include a reflecting mirror

An optical scanning device includes a plurality of stations, each of which includes an light source, a deflector (polygon scan), a scanning optical element, and a housing. The light source emits a light beam to a plurality of surfaces to be scanned. The deflector deflects light beams emitted from the light source. The scanning optical element scans the surfaces to be scanned with light spots of the optical beams deflected by the deflector. The housing houses therein the light source, the deflector, and the scanning optical element. The scanning optical element is secured to the housing so that directions of scanning-line curves caused by temperature change match between the surfaces to be scanned.

Optical scanning device and image forming apparatus

An optical scanning device that optically scans a surface to be scanned in a main-scanning direction includes a light source; an optical deflector that has a reflective surface rotating on an axis of rotation of the reflective surface and deflects a light beam emitted from the light source; a scanning optical system that guides the light beam deflected by the optical deflector to the surface to be scanned; and a flow guide member that is provided near the optical deflector and turns back a flow of air generated by rotation of the reflective surface toward the reflective surface.

Flow guide for optical scanning device and image forming apparatus

A holding mechanism for a long length optical element, which extends in a main scanning direction that is a movement direction of a deflected luminous flux by an optical deflector, and leads the deflected luminous flux to a scanned surface, includes; a holding member which is placed in a sub-scanning direction orthogonal to the main scanning direction and holds the long length optical element in at least two places. The holding member has, an adjusting section which deflects the long length optical element in the sub-scanning direction and controls a tilt of the long length optical element in a sub-scanning cross-section and/or occurrences of a tilt distribution in a longitudinal direction in the sub-scanning cross-section.

Holding mechanism for long length optical element, optical scanning device, and image forming device

An optical scanning device includes: a light source unit that includes a light emitting unit composed of a laser light source emitting linearly polarized light inside a package member; a deflector that deflects a light beam emitted from the light emitting unit; a pre-deflector optical system arranged on an optical path between the light emitting unit and the deflector; and a scanning optical system that scans a target surface to be scanned with the light beam deflected by the deflector. The pre-deflector optical system includes at least two parallel plate optical elements each composed of a transparent medium having an incident surface and an exit surface parallel to each other. The parallel plate optical elements are arranged to be tilted in inclination that is opposite to each other in a plane of polarization of the linearly polarized light.

An optical scanning apparatus, an image formation apparatus, and a phase modulation method are disclosed. The optical scanning apparatus includes a liquid crystal device for deflecting an optical beam irradiated by a semiconductor laser. The driving voltages for the liquid crystal device are controlled based on, e.g., the temperature of the liquid crystal device so that degradation of the diameter of a spot of the optical beam due to wavefront aberration is prevented.

Optical scanning apparatus, an image formation apparatus, and a phase modulation method

An optical scanning apparatus for scanning a surface to be scanned includes: a light source that emits laser beam; a deflector that deflects the laser beam emitted from the light source; a plurality of optical scanning elements that introduce the deflected laser beam to the surface to be scanned; a housing that holds therein at least one of the light source, the deflector, and the scanning optical elements; a light receiving element that receives the deflected laser beam; a mirror that introduces the deflected laser beam to the light receiving element; and a holder that is provided on the housing and that holds the light receiving element and the mirror integrally.

Optical scanning apparatus and image forming apparatus

An optical scanning characteristic control method is applied to an optical scanning system in which a beam is deflected, and the deflected beam is converged and directed toward a scanning surface, so that optical scanning of the scanning surface is performed by an optical spot formed thereon by the deflected beam. The method comprising the steps of a) disposing a beam deflection control device on the light path of the beam before it is incident on the scanning surface; and b) controlling a beam deflection amount of the beam deflecting device provide to an incident beam so as to control a scanning characteristic of the optical scanning.

Image forming system employing effective optical scan-line control device

A disclosed optical scanning device scans an object scanning surface with a light beam projected from a light source and traveling through an optical system. The optical scanning device includes a liquid crystal element configured to modulate a phase. The liquid crystal element is driven by electric signals and provided on a light path between the light source and the object scanning surface. The liquid crystal element generates different power components in a main scanning direction and a sub scanning direction under temperature variations.

Optical scanning device, image forming apparatus, and liquid crystal element

An optical splitting member splits a light beam emitted by a light source into first light beam and second light beam. A coupling member couples the first light beam. An optical system converges the second light beam on a light receiving unit. A holding member holds the light source, the optical splitting member, the coupling member, and the optical system. A supporting member supports the holding member so that the holding member is rotatable about an optical axis of the light beam.

Light source device, optical scanning device, and image forming apparatus

A light source unit is provided, which includes a light source with a plurality of light emission portions two-dimensionally arranged; a substrate on which the light source is mounted; a first support portion supporting the substrate; a bias member biasing the substrate towards the first support portion; a coupling element coupling a light beam emitted from the light source; a second support portion supporting the coupling element; a holding member holding a position of the substrate relative to the first support portion, a fitting portion provided in each of the first and second support portions to rotatably fit the first and second support portions into each other around an optical axis of the light source; and a fastening member integrally fastening the first and second support portions.

Light source unit, optical scan apparatus, and image formation apparatus

An optical scanning device includes a laser-beam-phase-modulatable liquid crystal device. The liquid crystal device has stripe-like electrode patterns arranged in one direction, with a provision of a part for changing an effective value of a driving voltage separately for each of stripe-like electrode patterns.

Optical scanning device, image forming apparatus and liquid crystal device driving method

A light source unit is provided which includes a light source with a plurality of light emission portions two-dimensionally arranged; a substrate on which the light source is mounted; a first support portion supporting the substrate; a bias member biasing the substrate towards the first support portion; a coupling element coupling a light beam emitted from the light source; a second support portion supporting the coupling element; and a holding member holding a position of the substrate relative to the first support portion.

Growing community of inventors

Kanagawa, Japan

Taku Amada