Patent ID: 7764301
Filing Date: 2010-07-27
Classification: B41J,G02B

Abstract:
1. An optical scanning device comprising: a deflecting unit that deflects a plurality of beams in a main scanning direction to a writing area of a surface to be scanned for scanning the writing area, wherein the plurality of beams include a leading beam and a following beam, the leading beam is incident on a surface of the deflecting unit, the surface of the deflecting unit when deflecting the leading beam forming a first angle with respect to the main scanning direction, and the following beam is incident on the surface of the deflecting unit, the surface of the deflecting unit when deflecting the following beam forming a second angle with respect to the main scanning direction main scanning direction, the second angle being smaller than the first angle; a first sensor that detects the plurality of beams deflected by the deflecting unit to be incident on a point on a first side of the writing area, and outputs a signal in response to each of detected beams including the leading beam and the following beam; and a modulating system that starts modulating the plurality of beams in synchronization with a timing when the first sensor detects the following beam after detecting the leading beam; and a second sensor that detects the plurality of beams deflected by the deflecting unit incident on a point on a second side of the writing area, and outputs a signal in response to each of detected beams including the leading beam and the following beam, wherein the modulating system detects completion of scanning of the writing area in synchronization with a timing when the second sensor detects the leading beam.