An image forming apparatus includes an optical scanning apparatus configured to scan a photoreceptor with a light beam having a scanning speed changing in accordance with a position in a main scanning direction, and a control unit configured to output a horizontal synchronization signal for determining a timing at which an image signal generation unit outputs an image signal to the optical scanning apparatus. The optical scanning apparatus includes a beam detection sensor that outputs a beam detection signal indicating a detection timing of the light beam, and a memory that stores timing correction information. The control unit corrects, based on the timing correction information, a reference time, and outputs the horizontal synchronization signal to the image signal generation unit at a timing after a period corrected from reception of the beam detection signal.

An image processing apparatus includes a memory, a scanner, and a processor configured to: control the scanner to read an image formed on a sheet along a reading direction, and store data of the read image in the memory, determine a plurality of regions of the image, select one of the regions based on a whiteness or saturation level of color thereof, and add a first image indicating the reading direction to said one of the regions, and store data of the image to which the first image has been added in the memory.

A write control apparatus is for receiving one page worth of image data and performing processes, and writing an image by exposing a photoconductor. The write control apparatus includes a write control unit including a process function unit for performing the processes; a computer for generating setting values of parameters used by the process function unit; and first and second memories for storing the setting values. When the computer sends a trigger signal to start image formation to the write control unit, the second memory stores one page worth of the setting values stored in the first memory, and the setting values of a desired page among a plurality of pages worth of the setting values stored in the second memory are applied to operations by the process function unit when the write control unit controlled by the computer writes an image of the desired page.

A method of operating a printing system includes determining whether ghosting is expected on a photoreceptor and applying power to a laser applied to the photoreceptor based on whether the ghosting is expected.

A system and method to compensate for ghost appearances on a print due to a previous job, the method comprising defining areas in which ghosting is expected or detected and recording the image on a photoreceptor by selectively changing the parameters of the system as a function of position, to compensate for the effects of ghosting in ex-image and ex-nonimage areas.

A scanning optical device includes: a first light source device configured to emit a first beam; a second light source device configured to emit a second beam; a deflector configured to deflect the first beam and the second beam; a first scanning optical system including a first scanning lens and configured to form an image on a first surface to be scanned using the deflected first beam; a second scanning optical system configured to form an image on a second surface to be scanned using the deflected second beam; a cover including a cover base wall and a first light-shielding wall; and a frame including a frame base wall and a second light-shielding wall. The first scanning lens has an incident surface and an emitting surface opposite the incident surface. The first light-shielding wall overlaps with the incident surface. The second light-shielding wall overlaps with the emitting surface.

An image forming apparatus includes: a setting unit configured to set an exposure luminance; and a processing unit configured to generate first image data, which is a set of bit data for controlling emission or non-emission of light-emitting elements of a exposure head, and second image data, which is obtained by increasing/decreasing light-emitting elements that emit light in the first image data. The processing unit is configured to generate the second image data by increasing/decreasing, in a first region, which excludes an edge region inside a region in which pieces of bit data indicating emission are contiguous in the first image data, bit data indicating emission, according to a ratio of a setting value of the exposure luminance and a reference value of the exposure luminance.

A color image forming apparatus includes a photoconductor on which an image is formed; an optical writing device to expose the photoconductor with light, the optical writing device including: a light emitter to emit light; a deflector including a multifaceted reflector rotationally driven to deflect the light emitted from the light emitter to scan the photoconductor with the light in a scanning direction; a synchronization detector to detect a write start timing of the light to be irradiated onto the photoconductor from the deflector; circuitry configured to: control the light emitter to emit light; and correct a detection shift of the synchronization detector generated by a fluctuation of a light amount of the light incident on the synchronization detector; and adjust the write start timing to correct a color shift.

An optical scanner includes: deflector deflecting a beam from a light source to scan scanned surface in main-scanning direction; and a first element closest to scanned surface and guides the beam to scanned surface, in which thickness of first element in optical-axis direction in main-scanning section changes in main-scanning direction, first element includes an optical surface whose normal on main-scanning section is tilted thereto, the normal tilt amount changes in main-scanning direction, and a position in main-scanning direction where interval in optical-axis direction between both ends in sub-scanning direction of effective region of the optical surface in sub-scanning section is maximum, a position in main-scanning direction where a thickness in optical-axis direction of first element in main-scanning section is maximum, and maximum image height in main-scanning direction on scanned surface are appropriately set in region on one side of the optical surface relative to optical axis in main-scanning direction.

An image forming apparatus includes a laser unit including a semiconductor laser, a polygon mirror, an LD driver, and an LD board including an LD reference potential section. The image forming apparatus includes a photoconductor drum, a controller configured to output a pulse-width modulation signal to indicate a reference potential, and a main board including a main reference potential section configured to provide the reference voltage of the controller, the main reference potential section being electrically connected to the LD reference potential section via a harness. The LD board includes a voltage generation circuit configured to generate a particular voltage, a switching circuit configured to output an ON-voltage and an OFF-voltage alternately based on the pulse-width modulation signal, and a smoothing circuit configured to generate the reference voltage by smoothing the ON-voltage and the OFF-voltage output by the switching circuit.