An optical writing device and an image forming apparatus incorporating the optical writing device. The optical writing device includes two or more light sources, a pixel clock generator to measure a scanning speed of one of the two or more light sources and generate a pixel clock of a cycle corrected according to the measured scanning speed, a pulse data generation and output unit to generate pulse width data and shift data for the pixel clock generated by the pixel clock generator to output the generated pulse width data and the generated shift data for each one of the two or more light sources, and a plurality of image pulse generation and output units to generate an image pulse. In the optical writing device, the plurality of image pulse generation and output units are supplied with the pixel clock in common.

An image forming apparatus includes a conveyance part, an image forming part, a sheet detection sensor, a sensor unit, and a controller. The sheet detection sensor, in which a plurality of sensor blocks each with a plurality of sensor elements mounted thereon at specified intervals are arrayed in a sheet width direction, detects an edge position in the sheet width direction on a basis of scanning image data formed by reading of the sheet. The controller is enabled to execute a calibration of inserting, into the scanning image data, interpolation pixels for compensating an error between an edge position detected by the scanning image data and an actual edge position.

A system includes a mirror controller driving fast and slow axis mirrors of a projector with fast and slow axis drive signals to reflect a collimated light beam in a scan pattern across the target. The scan pattern includes trace lines which cause display of an input video stream on the target, and retrace lines which operate to return the slow axis mirror to a proper location to begin a next frame of the scan pattern. The slow axis drive signal is generated to maintain a number of trace lines in each frame of the scan pattern constant across frames, but the slow axis drive signal is modified to lock a phase and frequency of the displayed video to a phase and frequency of the input video stream by changing a number of retrace lines in each frame of the scan pattern on a frame-by-frame basis by a non-integer number.

An image forming apparatus includes a conveyance part, an image forming part, a sheet detection sensor, a sensor unit, and a controller. The sheet detection sensor, in which a plurality of sensor blocks each with a plurality of sensor elements mounted thereon at specified intervals are arrayed in a sheet width direction, detects an edge position in the sheet width direction on a basis of scanning image data formed by reading of the sheet. The controller is enabled to execute a calibration of inserting, into the scanning image data, interpolation pixels for compensating an error between an edge position detected by the scanning image data and an actual edge position.

An optical writing device and an image forming apparatus incorporating the optical writing device. The optical writing device includes two or more light sources, a pixel clock generator to measure a scanning speed of one of the two or more light sources and generate a pixel clock of a cycle corrected according to the measured scanning speed, a pulse data generation and output unit to generate pulse width data and shift data for the pixel clock generated by the pixel clock generator to output the generated pulse width data and the generated shift data for each one of the two or more light sources, and a plurality of image pulse generation and output units to generate an image pulse. In the optical writing device, the plurality of image pulse generation and output units are supplied with the pixel clock in common.