Scan timing detection device, optical scanning device, and image forming device

摘要

PROBLEM TO BE SOLVED: To provide an optical scanning device which detects the synchronous timing highly accurately in reciprocation scanning with a simple configuration.SOLUTION: An optical scanning device 10 comprises: BD sensors 13 which are arranged so as to be adjacent to each other along the scanning direction in a scanning range of an optical beam and include photo-diodes outputting detection signals at a level corresponding to a light reception amount; a pulse signal generation circuit 15 which generates a pulse signal having timing at which the magnitude relation between the detection signals of the optical beam detected by the photo-diodes is switched with level change as a rising edge, and a pulse signal having the timing as a falling edge for each reciprocation direction; and a pulse signal selection circuit 16 which generates an identification signal corresponding to the scanning direction from the detection signals of the optical beam detected by the photo-diodes and selects the pulse signal having prescribed one edge of the pulse signal having the rising edge and the pulse signal having the falling edge from the identification signal.SELECTED DRAWING: Figure 4