Abstract: In a light-source driving device, a high-frequency clock generating circuit generates two high-frequency clock signals having mutually different phases, an image-data creating circuit creates a plurality of image data corresponding to a plurality of light-emitting units according to image information, and a write control circuit creates a plurality of modulated data corresponding to the light-emitting units from the plurality of image data and separately controls output timings of the plurality of modulated data by using a time, as a unit, corresponding to a phase difference between the two high-frequency clock signals. The write control circuit includes two data switching circuits that set a correspondence relation between image data and PWM data based on one of a relation between an array of the light-emitting units and an array of a plurality of light spots and a relation between a surface to be scanned and a main scanning direction.

Abstract: A laser driving device in the embodiment includes: a laser light source that emits laser light; a light source drive control unit that adjusts a light amount of laser light emitted from the laser light source constant and controls on-off driving of the laser light source; a light amount adjustment element that is disposed in an optical path of laser light emitted from the laser light source and is capable of electrically changing transmittance or reflectance of the laser light that is entered thereinto; and a peak light amount control unit that controls the transmittance or the reflectance of the light amount adjustment element, so as to adjust a peak light amount of the laser light that is output from the light amount adjustment element after having traveled through or having been reflected by the light amount adjustment element.

Abstract: A write control circuit includes a first data switching circuit that sets a correspondence relationship between signals from line buffers and input signals to a delay circuitry, based on a signal from a CPU; and a second data switching circuit that sets a correspondence relationship between output signals of the delay circuitry and drive signals, based on a signal from the CPU. This enables a plurality of light emitting sections to be driven properly, regardless of a main scanning direction and an arrangement of a plurality of light spots being in any of CASE-1 to CASE-4 in an optical scanning device.

Abstract: A disclosed optical scanner includes a light source unit and a control unit configured to control the light source unit. Light emitted from the light source unit is scanned to expose a scan object surface and form an image on the scan object surface. The light source unit includes plural light sources arranged at a density equal to N (N being an integer of two or more) times higher than a density of pixels on the scan object surface. The control unit controls the light source unit such that one pixel is formed by at least two of the light sources.

Abstract: A light-source driving device includes a high-frequency clock generating circuit that generates high-frequency clock signals of which phases are different from each other; an image-data generating circuit that generates a plurality of pieces of image data corresponding to light emitting units in accordance with image information; a write control circuit that generates a plurality of pieces of modulation data corresponding to the light emitting units based on the image data and adjusts output timing of the modulation data individually in units of time corresponding to a phase difference of the high-frequency clock signals; and a light-source driving circuit that drives the light emitting units based on a plurality of pieces of PWM data output from the write control circuit.

Abstract: Apparatus that forms an image according to image information includes density sensors that detect image density variations in main and sub-scanning directions. A processing device generates correction data for correcting a light source output to suppress the density variations based on detection results. The processing device modifies the correction data such that the light source output after the correction is at least a minimum rated output at a position at which the output after the correction is lower than the minimum rated output, in the relation between a position on the surface of the photosensitive element in the main-scanning direction and the output after the correction, and modifies the correction data such that the light source output after the correction is at most a maximum rated output at a position at which the output after the correction is higher than the maximum rated output.

Abstract: A light source device includes a light source that includes a vertical cavity surface emitting laser; a drive circuit that drives the light source; and a circuit board that includes at least one mounting surface on which the light source and the drive circuit are mounted. The light source is mounted on a first area of the mounting surface, the drive circuit is mounted on a second area of the mounting surface, and a highest end of the first area is at a same height or lower than a lowest end of the second area with respect to a gravity direction.

Abstract: An image forming apparatus that forms an image includes: a photosensitive element; an optical scanning device that includes a light source, and scans a surface of the photosensitive element in a main scanning direction with light emitted from the light source to form a latent image; a developing unit that develops the latent image; a photosensitive element period detecting sensor that detects a rotation period of the photosensitive element; a density sensor that detects a density variation of an image developed by the developing unit, in a sub scanning direction; and a processing device that corrects a driving signal of the light source according to the image information, based on an output signal of the density sensor and an output signal of the photosensitive element period detecting sensor.

Abstract: An optical scanning device includes n-odd (n?2) light sources disposed at different positions at least in a sub-scanning direction, a pixel forming part in which one pixel is depicted by light beams emitted from m-odd (n?m?2) light sources of the n-odd light sources and a distance of adjacent light sources for emitting the light beams in the sub-scanning direction is less than 5 ?m, and a light source driving control part configured to control an emitting state of the light sources for depicting the one pixel and conduct an emission driving control for moving a gravity center of the one pixel in the sub-scanning direction.

Abstract: A laser driving device in the embodiment includes: a laser light source that emits laser light; a light source drive control unit that adjusts a light amount of laser light emitted from the laser light source constant and controls on-off driving of the laser light source; a light amount adjustment element that is disposed in an optical path of laser light emitted from the laser light source and is capable of electrically changing transmittance or reflectance of the laser light that is entered thereinto; and a peak light amount control unit that controls the transmittance or the reflectance of the light amount adjustment element, so as to adjust a peak light amount of the laser light that is output from the light amount adjustment element after having traveled through or having been reflected by the light amount adjustment element.

Abstract: An optical scanning device includes a deflecting unit that deflects a laser beam from a light source in a main-scanning direction; a scanning imaging unit that focuses the laser beam deflected by the deflecting unit on a scanning surface and scans the scanning surface with focused laser beam; and a light receiving unit that detects optical intensity of the laser beam and a synchronous timing in the main-scanning direction and that includes a plurality of photodetecting elements arranged on a substrate in the main-scanning direction.

Abstract: A laser driving unit drives a semiconductor laser apparatus including a plurality of light sources, includes a light detecting part to detect light emissions from the light sources, a driving current generator to generate a driving current based on an input signal, an auxiliary driving current generator to generate an auxiliary driving current in an initial time period of an ON-time of the driving current, and an auxiliary current set part to set an auxiliary amount of the auxiliary driving current to be added to the driving current, for each of the light sources, based on a difference between the light emissions detected by the light detecting part and a target light emission of the light sources.

Abstract: A pixel clock generator that generates a pixel clock to regulate a drive timing of a scanning light source includes a data generating circuit that generates phase data based on a phase data pattern to correct an uneven scanning speed and fluctuation of scanning widths, and a pixel clock generating circuit generates a pixel clock having a long cycle based on a high-frequency clock and that performs a phase shift for the pixel clock based on the high-frequency clock. The phase pattern is set-such that difference in an amount of the phase shift between the pixel clocks adjacent to each other does not exceed a basic amount of the phase shift of the pixel clock generating circuit.

Abstract: A laser driving device that drives a semiconductor laser based on a light-emitting signal includes an expansion circuit that expands a pulse width of the light-emitting signal based on a known difference between the pulse width of the light-emitting signal and a lighting pulse width of the semiconductor laser when the semiconductor laser emits light according to the light-emitting signal, and a driver that outputs a driving signal to the semiconductor laser according to an output signal of the expansion circuit.

Abstract: A light-source drive control unit divides each pixel of the image data into a plurality of subpixels, deletes certain subpixels from the image data in accordance with predetermined correction data, shifts remaining subpixels in the sub-scanning direction thereby obtaining reduced image data, and controls a plurality of light sources based on the reduced image data in such a manner that one line of the subpixels is formed with a light beam emitted from a corresponding one of the light sources.

Abstract: A pixel clock and pulse-modulation-signal generating device includes a high-frequency-clock generating unit that generates a high-frequency clock; a modulation-data generating unit that generates, based on pixel control data that specifies a pixel length and image data, phase data that indicates a transition timing of a pixel clock and modulation data that indicates a desired bit pattern that corresponds to the image data; a pixel-clock generating unit that generates a pixel clock based on the high-frequency clock, the phase data, and a horizontal synchronization signal; and a serial-modulation-signal generating unit that inputs the modulation data, and outputs a pulse modulation signal in a serial pulse string based on the high-frequency clock.

Abstract: An image forming apparatus includes an optical scanning device that scans a scan area on an image carrier with light flux containing image information and writes the image information onto an image area in the scan area. In the optical scanning device, a first light receiving unit receives light flux emitted from a light source and reflected by a reflecting optical unit; a second light receiving unit receives light flux that passes through an aperture of the reflecting optical unit, is deflected by a deflecting unit, and heads for outside the image area within the scan area; and a control unit controls a drive signal of the light source based on signals output from the first and second light receiving units.

Abstract: An optical scanning apparatus that includes a light source unit having plural main light sources that are two-dimensionally arranged in the main scanning direction and the sub scanning direction, and plural sub light sources that are arranged between rows of the main light sources aligned in the main scanning direction. The optical scanning apparatus also includes an optical system configured to scan light emitted from the light source unit on a scanning object to form an image on the scanning object, and a control apparatus configured to adjust a main scanning direction image position by controlling two of the main light sources that are juxtaposed to each other with respect to the main scanning direction and adjust a sub scanning direction image position by controlling a main light source and a sub light source that are adjacent to each other.

Abstract: An optical scanning device of the invention includes: n-odd (n?2) light sources disposed at different positions at least in a sub scanning direction; a light source driving control part configured to control a light emitting state of the light source; and a sub-scanning pixel position detecting part configured to depict one pixel with m-odd (n?m?2) light sources of the n-odd (n?2) light sources and to detect a deviation in position of the one pixel in a sub scanning direction, wherein the light source driving control part is configured to correct the deviation in position of the one pixel in the sub scanning direction at a resolution equal to or higher than a density of the pixel, depicted with the m-odd light sources, by controlling the light emitting state of the m-odd light sources on the basis of a result of detection with the sub-scanning pixel position detecting part.

Abstract: There provided is a semiconductor laser control device which including plural light sources that are configured with eight or more semiconductor laser elements, a one detecting section that detects a light power of the light sources, a light power control unit that compares a signal according to a light power detected by the detecting section with a control signal corresponding to a predetermined light power to control a current supplied to the light sources, and a voltage clamp circuit that functions as an overvoltage preventing means for the detecting section when turning on each of the light sources to perform light power control.