Abstract: An optical writing apparatus includes a deflecting part having a deflection plane for deflecting a plurality of light beams, a synchronization detection mirror for reflecting the plurality of light beams from the deflecting part, a synchronization detection part for detecting the timing for deflecting the plural light beams reflected from the synchronization detection mirror, and a housing for housing the deflecting part and the synchronization detection part. The synchronization detection part includes a lens for converging the plural light beams reflected from the synchronization detection mirrors, a light detection plate for detecting the plural light beams converged by the lens, and a holding member for holding the lens and the light detection plate.

Abstract: An image fixing device for use in an image forming apparatus. The fixing device includes a fixing member which fixes a toner image on a recording medium at a nip area, a pressurizing member which pressures the recording medium toward the fixing member at the nip area, a carbon lamp which emits infrared rays, and a reflecting member which reflects the infrared rays to the nip area.

Abstract: An optical scanning device includes a polygon mirror, a beam detector, a correcting unit, and a controller. The polygon mirror deflects and scans a light beam in a main scanning direction on a surface of an image carrier. The beam detector detects a beam position of the deflected light beam in a sub-scanning direction. The correcting unit calculates a correction amount of out-of-color registration based on the beam position, and corrects out-of-color registration in the sub-scanning direction based on the correction amount. The controller controls, during correction of out-of-color registration, a deflection speed of the deflector to be less than a deflection speed for writing a latent image on the surface of the image carrier.

Abstract: This recording-medium conveying device comprises a conveying belt, the conveying belt, a belt charging unit, and a pressing roller. The conveying belt is wound around a driving roller and a driven roller so as to convey a recording medium to an image recording part. The conveying belt includes an insulating layer formed at one side contacting the recording medium. The belt charging unit is provided in contact with the insulating layer so as to charge the insulating layer with a positive charge and a negative charge alternately in a moving direction of the conveying belt by applying an AC bias to the conveying belt. The pressing roller presses the conveying belt against the driving roller so as to prevent the conveying belt from slipping on the driving roller.

Abstract: An image forming apparatus is provided with a light scanning device that directs laser beams emitted from a plurality of laser light sources onto a plurality of photo conductive members via focusing device which includes optical elements and a deflecting device that deflects the beams in a main scanning direction; an image forming device which forms visible images of different colors from images written onto the photoconductive members by the light scanning device; and an intermediate transfer member or a recording sheet transport member capable of carrying the visible images formed on the photoconductive members. When in detection mode, a control device controls the correction of color registration errors between each color forms patterns on an intermediate belt by means of the image forming device, detects the patterns by a color registration error detection sensor, and stores the color registration error correction values obtained from the detection output of the sensor in a memory device.

Abstract: An image forming apparatus includes a first support member, an image carrying member configured to carry a toner image thereon, and an optical writing apparatus connected to the first support member and configured to form an electrostatic latent image on the image carrying member. The optical writing apparatus includes an optical system having at least one optical element, a first casing configured to support the optical system, and a second casing configured to encase the first casing and to prevent intrusion of dust to the optical system.

Abstract: An image forming apparatus includes a first support member, an image carrying member configured to carry a toner image thereon, and an optical writing apparatus connected to the first support member and configured to form an electrostatic latent image on the image carrying member. The optical writing apparatus includes an optical system having at least one optical element, a first casing configured to support the optical system, and a second casing configured to encase the first casing and to prevent intrusion of dust to the optical system.

Abstract: A beam detecting unit detects at least one of a position of an optical beam in a sub scanning direction and a position of the optical beam in a main scanning direction. A color-misalignment correcting unit changes an optical-beam irradiating position on a photosensitive element based on a result of detection by the beam detecting unit. The beam detecting unit is arranged between an optical element that is closest to a corresponding photosensitive element and the corresponding photosensitive element.

Abstract: An optical scanning device includes a plurality of light sources, a deflector, optical systems, and a plurality of light shielding units to shield flare light from an opposite optical system. Two light shielding units are arranged not to satisfy ?=n(360/x) degrees, where ? is an angle formed by a line from a portion of one light shielding unit nearest the deflector to a rotation axis of the deflector and a line from a portion of the other light shielding unit nearest the deflector to the rotation axis of the deflector with the rotation axis of the deflector being an apex angle, x is the number of mirror faces of the deflector, and n is an integer not more than x.

Abstract: An image forming apparatus includes at least one image carrier. An endless transfer belt directly or indirectly receives toner images and pattern toner images from the image carrier and is spanned around and surrounds a drive roller and driven rollers. A position shift detector detects positions of pattern toner images formed on the image carrier. Pattern toner images are formed on the image carrier at an interval of 1/N of a circumferential length of the image carrier, where N is an integer equal to or greater than 1. The pattern toner images are transferred from the image carrier onto the transfer belt over one cycle length of the transfer belt. The position shift detector detects positions of the pattern toner images to obtain position shift data. Moving average values of N number of the position shift data are calculated.

Abstract: An optical writing apparatus includes a deflecting part having a deflection plane for deflecting a plurality of light beams, a synchronization detection mirror for reflecting the plurality of light beams from the deflecting part, a synchronization detection part for detecting the timing for deflecting the plural light beams reflected from the synchronization detection mirror, and a housing for housing the deflecting part and the synchronization detection part. The synchronization detection part includes a lens for converging the plural light beams reflected from the synchronization detection mirrors, a light detection plate for detecting the plural light beams converged by the lens, and a holding member for holding the lens and the light detection plate.

Abstract: An image forming apparatus includes a first support member, an image carrying member configured to carry a toner image thereon, and an optical writing apparatus connected to the first support member and configured to form an electrostatic latent image on the image carrying member. The optical writing apparatus includes an optical system having at least one optical element, a first casing configured to support the optical system, and a second casing configured to encase the first casing and to prevent intrusion of dust to the optical system.

Abstract: An optical scanning apparatus including a laser diode light source fittingly inserted into a holding member. The holding member is formed of a resin material having a thermal conductivity of 0.7 w/m°K or more and filled with either glass fiber or metal oxide or both, or aluminum. A heat radiating fin projecting radially is formed on an outer circumferential portion of the cylindrical body of the holding member. With this structure, temperature rise due to heat emission from the laser diode can be suppressed and deterioration of the laser diode can be prevented. This structure simply and inexpensively provides stable optical properties to optical scanning and image forming devices.

Abstract: There is provided an image forming apparatus able to form color images of higher quality without color deviation in an inexpensive way. A displacement driving unit is provided to move an optical element unit to displace a beam spot on a photoconductor in the sub scanning direction. A first detection unit is provided to detect the turning cycle of a transfer member, and a second detection unit is provided to detect writing timing of a laser beam from the optical element unit on the photoconductor. When writing a number of toner images on the photoconductor in sequence, the optical element unit is moved and the beam spot is displaced on the photoconductor in the sub scanning direction to correct the writing position on the photoconductor and eliminate deviation of image transfer positions on the transfer member.

Abstract: This recording-medium conveying device comprises a conveying belt, the conveying belt, a belt charging unit, and a pressing roller. The conveying belt is wound around a driving roller and a driven roller so as to convey a recording medium to an image recording part. The conveying belt includes an insulating layer formed at one side contacting the recording medium. The belt charging unit is provided in contact with the insulating layer so as to charge the insulating layer with a positive charge and a negative charge alternately in a moving direction of the conveying belt by applying an AC bias to the conveying belt. The pressing roller presses the conveying belt against the driving roller so as to prevent the conveying belt from slipping on the driving roller.

Abstract: An optical scanning device including a housing, a first carriage carrying a light source and a first mirror, a second carriage carrying second and third mirrors, the second carriage cofigured to move in a sub-scanning direction at one-half of a speed of the first carriage, first and second timing pulleys spaced apart in the sub-scanning direction, a timing belt spanned around the first and second timing pulleys to reciprocate the first carriage in the sub-scanning direction, a drive device to drive the first timing pulley, flat pulleys supported by the second carriage and spaced apart in the sub-scanning direction by a moving distance of the second carriage, a flat belt spanned around the flat pulleys to reciprocate the second carriage in the sub-scanning direction, an engaging member engaging the timing and flat belts to the first carriage, and a fixing member fixing the flat belt to the housing.

Abstract: An image forming apparatus includes at least one image carrier. An endless transfer belt directly or indirectly receives toner images and pattern toner images from the image carrier and is spanned around and surrounds a drive roller and driven rollers. A position shift detector detects positions of pattern toner images formed on the image carrier. Pattern toner images are formed on the image carrier at an interval of 1/N of a circumferential length of the image carrier, where N is an integer equal to or greater than 1. The pattern toner images are transferred from the image carrier onto the transfer belt over one cycle length of the transfer belt. The position shift detector detects positions of the pattern toner images to obtain position shift data. Moving average values of N number of the position shift data are calculated.

Abstract: This recording-medium conveying device comprises a conveying belt, the conveying belt, a belt charging unit, and a pressing roller. The conveying belt is wound around a driving roller and a driven roller so as to convey a recording medium to an image recording part. The conveying belt includes an insulating layer formed at one side contacting the recording medium. The belt charging unit is provided in contact with the insulating layer so as to charge the insulating layer with a positive charge and a negative charge alternately in a moving direction of the conveying belt by applying an AC bias to the conveying belt. The pressing roller presses the conveying belt against the driving roller so as to prevent the conveying belt from slipping on the driving roller.

Abstract: A color shift correcting method for correcting a color shift due to misregistration of images in different colors, where a multi-color image is formed by developing latent one-color images written onto respective image carriers by an optical writing device, and directly or indirectly transferring developed one-color images onto a movable element, said method comprising the step of:

Abstract: There is provided an image forming apparatus able to form color images of higher quality without color deviation in an inexpensive way. A displacement driving unit is provided to move an optical element unit to displace a beam spot on a photoconductor in the sub scanning direction. A first detection unit is provided to detect the turning cycle of a transfer member, and a second detection unit is provided to detect writing timing of a laser beam from the optical element unit on the photoconductor. When writing a number of toner images on the photoconductor in sequence, the optical element unit is moved and the beam spot is displaced on the photoconductor in the sub scanning direction to correct the writing position on the photoconductor and eliminate deviation of image transfer positions on the transfer member.