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: 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: 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 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 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: 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 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.

Abstract: A light scanning unit and an image forming apparatus employing the same. The light scanning unit deflects light in a main scanning direction, irradiates the light on a photoconductive drum, and includes a beam detecting sensor to detect a horizontal synchronization signal by receiving a part of the light beam reflected and scanned by a beam deflector, and leads of terminals of the beam detecting sensor are not exposed to the light beam to be scanned.

Abstract: An optical scanning apparatus includes a light source; and a rotational polygon mirror having N reflecting surfaces, the rotational polygon mirror being configured to reflect a light flux emitted from the light source so that a scanning surface is scanned along a main-scanning direction with reflected from the rotational polygon mirror. A width of the light flux incident on the rotational polygon mirror in a direction corresponding to the main-scanning direction is smaller than a width of each reflecting surface of the rotational polygon mirror in the direction corresponding to the main-scanning direction.

Abstract: A cover member to be attached to a housing including a bottom portion and a side wall, the cover member including: a closing surface configured to close an opening surrounded by the side wall; at least three protruding portions protruding from the closing surface so as to be located on an inside of the housing; and a protection portion configured to protect a circuit board fixed to the side wall, the protection portion having: a first opposed portion opposed to the circuit board and provided to stand on the closing surface; a second opposed portion opposed to the circuit board and protruding with respect to the first opposed portion away from the circuit board; and a connecting portion configured to connect the first opposed portion and the second opposed portion, wherein a length of the at least three protruding portions is larger than a length of the first opposed portion.

Abstract: A system for dampening fluid recovery in an ink-based digital printing system includes a seal manifold having a front seal portion, the front seal portion having an upper wall facing the imaging surface, the upper wall being configured to define an air flow channel with the imaging surface, the upper wall being contoured to form a distance between the upper wall and the imaging surface at an evaporation location that is less than distance between the upper wall and the imaging surface at locations interposing the evaporation location and a vacuum inlet channel of the seal manifold.

Abstract: An optical scanner includes a housing, a polygon mirror accommodated within the housing and configured to reflect light of a light source, a lens accommodated within the housing and arranged on an optical path of the light reflected by the polygon mirror, and a cover member. The cover member is mounted to the housing and is provided with an opening formed so as to expose at least a portion of the lens. The opening is closed by a seal member which is attached to a portion of the lens exposed from the opening and an outer wall surface of the cover member existing around the opening.

Abstract: An optical device includes: a light source that emits a light beam; a deflector that deflects the light beam in a main-scanning direction; and a scanning/image-forming optical system that includes a scanning lens that causes the light beam deflected by the deflector to converge to a scanned surface to form an image on the scanned surface. The scanning lens has refractive index gradient. At least one surface of the scanning lens is a tilt-decentered surface that has a tilt angle, which depends on a position in the main-scanning direction, in a sub-scanning direction. The tilt angle is set so as to compensate for variation, which results from the refractive index gradient, in direction of the light beam in the sub-scanning direction.

Abstract: An optical writing head positioning mechanism includes spacers provided between a latent image carrier for carrying an electrostatic latent image and an optical writing head for exposing the latent image carrier. The spacers each include at least one carrier contact surface that contacts the latent image carrier and at least one head contact surface that contacts the optical writing head to determine an interval between the latent image carrier and the optical writing head. The latent image carrier is in contact with a cleaning member that cleans a cleaning area on a surface of the latent image carrier. In at least one of the spacers, the at least one carrier contact surface includes plural carrier contact surfaces not disposed on edges of the cleaning area, and one of the edges of the cleaning area is located between two adjacent ones of the plural carrier contact surfaces.

Abstract: Density unevenness is suppressed even in an image that is formed by a multiple exposures method in which the same region on a photoreceptor is exposed multiple times with different laser light sources (light emitting elements), by adjusting the amounts of light of the respective lasers based on a density difference among test images. An image is formed for each group of light emitting elements grouped together for multiple exposures by dividing, in the main scanning direction, the region of a test image formed on a recording medium. The images formed for the respective multiple-exposure light emitting element groups are compared to one another in density, to thereby adjust the amounts of light of the respective laser light sources (light emitting elements) and reduce fluctuations in image density.

Abstract: An optical scanning device comprising: a light source that emits a laser beam; and a driving unit connected to the light source and configured to drive the light source; the driving unit comprising: a first storage unit that stores in advance therein a setting value for controlling output of the laser beam; a second storage unit that stores temporally therein the setting value stored in the first storage unit; a storage controller connected to the first storage unit and the second storage unit; and a voltage detector connected to the storage controller and configured to detect a voltage value supplied to the driving unit, wherein the storage controller, upon the voltage detector detecting that the voltage supply is resumed, transfers the setting value stored in the first storage unit to the second storage unit automatically.

Abstract: A laser marking system including a laser apparatus to supply a laser beam having a non-Gaussian irradiance distribution over a beam cross-section, the non-Gaussian irradiance distribution of the laser beam has a substantially uniform irradiance distribution over the beam cross-section, a spatial light modulator coupled to receive the laser beam, the spatial light modulator is controlled to generate an output laser beam including an optical pattern across the beam cross-section to mark a target object with the data code matrix, and an optical amplifier coupled to the spatial modulator to receive the laser beam output from the spatial light modulator and generate an amplified laser beam containing the same optical pattern as generated by the spatial light modulator, the amplified laser beam from the optical amplifier having a substantially uniform amplification across the cross-section of the beam, the amplified beam maintaining the substantially uniform irradiance distribution over its beam cross-section.