Patent ID: 6301021
Filing Date: 2001-10-09
Classification: H04N

Abstract:
A multi-beam optical apparatus comprising:a plurality of light sources for emitting a plurality of respective laser beams;scanning means for scanning an image carrier by deflecting all of the laser beams emitted from the light sources, and for deflecting only a particular laser beam also in another direction, the particular laser beam being monitored so as to form a plurality of reference patterns;light receiving means for receiving the particular laser beam deflected in said another direction by the scanning means;sync signal generating means for generating a single sync signal based on the particular laser beam received by the light receiving means;first control means for causing the laser beams to be emitted from the light sources in response to the single sync signal to form said plurality of reference patterns on the image carrier;detecting means for detecting said plurality of reference patterns formed on the image carrier by the laser beams under control of the first control means; andsecond control means for detecting shifts in positions of detected reference patterns and thereby controlling the timings of emitting the laser beams from the light sources.