摘要:
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.
摘要:
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.
摘要:
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.
摘要:
In a pixel clock creation method and device, a high frequency clock is created. A scanning time needed to scan a predetermined scanning length is detected in accuracy of half a period of the high frequency clock to output a detection value indicating the detected scanning time. The detection value and a predetermined target value are compared to output a comparison result. A phase data is created based on the comparison result. A pixel clock whose phase is controlled based on both the high frequency clock and the phase data is created.
摘要:
A circuit for driving a plurality of light emitting units includes a current biasing unit that biases a light emitting current with an overshoot current and supplies the resultant current to each of the light emitting units. The light emitting current is determined based on an amount of light emitted from each of the light emitting units.
摘要:
A deflector deflects a light beam emitted from a light source including a plurality of light-emitting units. A scanning optical system focuses the light beam deflected by the deflector on a scanning target surface. A monitoring photoreceiver receives a part of a light beam deflected by the deflector and directed toward an area within a scanning area outside an image area. A detecting unit individually detects emission powers of at least two light-emitting units based on an output signal of the monitoring photoreceiver in a single sweep of scanning.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.