Abstract: An optical scanning device includes a light source, a scanning portion that includes plural reflection surfaces, makes light beams incident to the reflection surface such that optical axis directions of the light beams emitted from the light emitting parts are tilted with respect to a direction perpendicular to the reflection surface, and scans the light beams in the main scanning direction through rotation, an optical system that includes an optical member made of a resin, is disposed between the scanning portion and the surface to be scanned, and makes the plural light beams incident to the surface to be scanned such that optical axes of the plural light beams are parallel to each other, and a correction portion that is provided in the optical system, and corrects positional deviation of scanning lines of the light beams in the sub-scanning direction on the surface to be scanned.

Abstract: The invention relates to a marking apparatus (100) for marking an object with laser light, comprising a plurality of lasers (10) and a control unit for individually activating each of the lasers to emit a laser beam according to a sign to be marked. A set of deflection means (30) for rearranging the laser beams into a two-dimensional array of laser beams is provided, the set of deflection means (30) comprises at least one deflection means (33) per laser beam, in particular at least one mapping mirror (33) or one optical waveguide per laser beam.

Abstract: The optical scanning device includes a photoreceptor, a light source unit, a plurality of correction value storage units and a light quantity correction unit. The scanning position in the photoreceptor is divided into a plurality of areas. The target correction amount of the light quantity is predetermined so as to change according to the scanning position. The correction value storage unit stores the light quantity correction value that is associated with each of the areas. The light quantity correction unit corrects the light quantity during scanning by using the light quantity correction value corresponding to the scanning position. The length of each of the areas is shorter in an area in which the variation in the target correction amount per unit length is greater. The light quantity correction value is determined based on the target correction amount according to the area corresponding to the light quantity correction value.

Abstract: A method of color laser marking a security document precursor including at least: a transparent biaxially stretched polyethylene terephthalate foil; at least one colorless color forming layer for generating a color different from black containing at least an infrared absorber a color forming compound and a polymeric binder; and a laser markable polymeric support or a laser markable layer for generating a black color; comprising the steps of: laser marking the colorless color forming layer through the transparent polymeric foil with a infrared laser used in continuous wave mode to generate a color different from black; and laser marking the laser markable polymeric support or the laser markable layer through the transparent polymeric foil with the same infrared laser but used in a pulsed mode to generate a black color.

Abstract: A first lens array unit includes a first lens array plate and a second lens array plate in which a plurality of lenses are provided in the main scanning direction, and a first light shielding member piece and a second light shielding member piece provided with a plurality of through holes corresponding to the lenses. The first lens array plate, the second lens array plate, the first light shielding member piece, and the second light shielding member piece are formed as one piece. The lens array is built by bending joints joining the lens array plates and the light shielding member pieces such that the lens is located to directly face the corresponding through hole.

Abstract: An optical scanning apparatus includes a light source configured to emit a light beam, a rotating polygon mirror configured to deflect the light beam such that the light beam scans a photosensitive member, an optical box to which the rotating polygon mirror is attached and which includes a first portion, and a holding member configured to hold the light source, including a second portion and a protrusion portion, and attached to the optical box such that the first portion of the optical box and the second portion of the holding member form a gap therebetween, wherein the holding member is attached to the optical box with an adhesive poured into the gap, and the protrusion portion is arranged toward the optical box from the holding member along a position in the gap into which the adhesive is poured to prevent the adhesive from falling off the position.

Abstract: A light-emitting substrate including: a first and second light-emitting devices each including terminals; and a substrate including a first hole and a second hole, the first hole and the second hole respectively having at least one receiving portion, wherein the receiving portion of the first hole receives the terminal of the first light-emitting device, and the receiving portion of the second hole receives the terminal of the second light-emitting device, a first line drawn through a center of the receiving portion of the first hole and a center of the first hole, and a second line drawn through a center of the receiving portion of the second hole and a center of the second hole are not aligned in line.

Abstract: An image forming apparatus that is capable of forming an electrostatic latent image on the surface of a photosensitive member with high position accuracy even when the shaft of the photosensitive member is off-centered. In the apparatus, exposure devices form electrostatic latent images on respective photosensitive drums, and developing devices develop the electrostatic latent images. An intermediate transfer belt rotates in contact with the photosensitive drums. A rotary encoder detects a rotational speed of a drum shaft of each photosensitive drum. An amount of off-centering of the drum shaft is detected, and a correction coefficient for correcting positional displacement of electrostatic latent images is calculated. A control unit corrects timing of exposure using the calculated correction coefficient, and controls the exposure device to form the image on the photosensitive drum based on the corrected timing of exposure.

Abstract: An image forming apparatus includes first and second photosensitive members; first and second light sources; a rotatable polygonal mirror; a first signal output portion; and a second signal output portion. The first light source emits the light at timing on the basis of the first signal, and the second light source emits the light at timing on the basis of the second signal so that latent images are formed on the first and second photosensitive members, respectively, and then are developed with developers to form developer images on the first and second photosensitive members, respectively, and then an image is formed by superposing the developer images. Before output of a second signal from the second signal output portion is started, the first light source emits the light on the basis of a first signal to start formation of the latent image on the first photosensitive member.

Abstract: A light scanning unit includes: a light source unit; a polygon mirror for deflecting and scanning light emitted from the light source unit, in a main scanning direction, and having a plurality of deflection surfaces and a plurality of edges at which adjacent deflection surfaces meet one another; an image forming optical system for condensing the deflected light; and a synchronization detection optical system for detecting a portion of light that is divided and reflected at an edge of the polygon mirror. The light scanning unit may be incorporated into an image forming apparatus.

Abstract: A 2-D scanning system uses a fast-rotating raster-polygon as a single scanning component to produce straight scan lines over a 2-D image surface. An approach angle of incident light beams to the raster-polygon is selected to minimize pin-cushion distortion of scan lines introduced by polygon scanning on the image surface, and a tilt angle of the rotational axis of the raster-polygon is selected to position said polygon-scanning distortion symmetrically on the image surface. In addition, scan optics are configured to generate a predetermined amount of barrel distortion of scan lines on the image surface to compensate for pin-cushion distortion introduced by polygon scanning.

Abstract: An image forming apparatus including a control unit configured to cause the light irradiation unit to irradiate the photosensitive member at an image forming portion to which toner particles adhere with light emitted from the light source by a first light emission amount, and cause the light irradiation unit to irradiate the photosensitive member at a non-image forming portion to which no toner particles adhere with light emitted from the light source by a second light emission amount that is smaller than the first light emission amount. The image forming apparatus further includes an adjusting unit configured to adjust the first light emission amount and the second light emission amount, and an acquisition unit configured to acquire information relating to a speed of surface of the photosensitive member. The adjusting unit is configured to change the second light emission amount according to information acquired by the acquisition unit.

Abstract: An image forming device includes a photoreceptor drum including a target surface that is scanned in a main scanning direction and a sub-scanning direction, an exposure head including a plurality of light emitting segments aligned in parallel to the main scanning direction, an exposure driving unit which selectively drives the plural light emitting segments, a storing unit which stores a profile where the respective positions of the plural light emitting segments correspond to a correction amount from the main scanning direction toward the sub-scanning direction at every position, and a correcting unit which smoothes a local change of the correction amount in the profile.

Abstract: A laser scanning unit includes a laser light source, rotating polygon mirror, drive motor, and entry detection, intensity detection, intensity adjustment, and drive control portions. The laser light source radiates first and second laser lights in first second directions, respectively. The drive motor rotates the polygon mirror reflecting the first laser light. The intensity adjustment portion adjusts the first laser light in accordance with the second laser light detected by the intensity detection portion, until a second time after a first time has elapsed since the first laser light entry detection by the entry detection portion. The drive control portion, upon adjustment by the intensity adjustment portion, drives the drive motor at a first rotation speed, wherein a return light entry timing is included within the first time or from when the second time has elapsed to the timing of the entry detection portion detection.

Abstract: An optical writing controller that controls a light source to expose a photoconductor and forms an electrostatic latent image on the photoconductor calculates a correction value for correcting a superimposing position where the developed images for different colors developing each of the electrostatic latent images formed on each of the multiple photoconductors are superimposed based on the detection signal output by a pattern detection sensor that detects a pattern for correcting the superimposing position, controls the multiple light sources to draw a predetermined pattern repeatedly in the sub-scanning direction so that stepwise patterns whose width in the main scanning direction varies with repetition are formed, and determines the width in the main scanning direction of the patterns for correcting based on the strength of the detection signal output by the pattern detection sensor.

Abstract: An optical scanning device includes: a driving unit that drives a light source that outputs multiple light beams; a deflecting unit that scans a scanning surface in a main-scanning direction by deflecting the light beams, the scanning surface moving at a predetermined line speed in a sub-scanning direction; and a control unit that changes number of the light beams according to the line speed by controlling the driving unit, changes a scanning speed of the deflecting unit in the main-scanning direction according to a difference between an exposure amount per unit length in the main-scanning direction after a change in the number of the light beams and a predetermined exposure amount, and changes light intensity of each of the light beams output by the light source according to an amount of a change in the scanning speed.

Abstract: An image forming apparatus includes an image bearing member; a charging device; an exposure device configured to expose intermittently for each unit area of the image bearing member charged by the charging device to form a latent image; a developing device configured to develop the latent image with developer; a signal output portion configured to output a first electric signal when the exposure device exposes a print area of the image bearing member, and output a second electric signal, which instructs the exposure device to shorten an exposure time per unit area more than an exposure time of the first electric signal, when the exposure device exposes a non-print area of the image bearing member; and a count portion, to which the first and the second electric signals are input from the signal output portion, configured to measure only the first electric signal without measuring the second electric signal.

Abstract: Provided is an image forming apparatus including a light scanning apparatus that emits a light flux to photosensitive surfaces of a plurality of photosensitive bodies arranged so that longitudinal directions are the same direction and that optically scans the plurality of photosensitive surfaces in the longitudinal direction, wherein a diameter of at least one of the plurality of photosensitive bodies is different from diameters of the other photosensitive bodies in a cross section perpendicular to the longitudinal direction, and in the cross section perpendicular to the longitudinal direction, a sign of ?1 and a sign of ?2 are different, wherein ?1 denotes an incident angle of a light flux incident on a first photosensitive body with a smallest diameter among the plurality of photosensitive bodies, and ?2 denotes an incident angle of a light flux incident on a second photosensitive body with a largest diameter, and a condition |?1|>|?2|>0 is satisfied.

Abstract: A pixel clock generating device includes a time interval detection unit detecting a time interval between a first signal and a second signal in each of cyclically repeating N (?2) time periods; a comparing unit cyclically selecting a target value from N target values corresponding to the N time periods and outputting an error indicating a difference between the detected time interval and the selected target value for each of the N time periods; a frequency calculation unit correcting a frequency of the pixel clock signal based on the error and cyclically generating a frequency specification signal indicating the corrected frequency for each of the N time periods; a high-frequency clock generating unit generating a high-frequency clock signal; and a pixel clock generating unit generating a pixel clock signal based on the frequency specification signal and the high-frequency clock signal.

Abstract: A clock signal generating circuit that generates a clock signal, the clock signal generating circuit including a clock signal generator configured to generate a reference clock signal; and a plurality of dividers to which the reference clock signal is to be input. A division ratio of at least one of the plurality of dividers varies based on division ratio data that defines the division ratio of the at least one of the plurality of dividers. The division ratio data represents a value that fluctuates around reference division ratio data with respect to time.