Patent ID: 6055005
Filing Date: 2000-04-25
Classification: H04N

Abstract:
An image forming apparatus, comprising:a charged photoreceptor moving in accordance with a motion signal;a light source emitting a light beam that is modulated in accordance with a modulation signal;a rotating polygon having a plurality of facets for reflecting the emitted light beam;a cylindrical mirror rotatable around an axis, said cylindrical mirror for directing the reflected light beam onto said moving photoreceptor;a controller producing said motion signal, said controller also producing said modulation signal so as to form a first latent image, comprised of a first scan line followed by a plurality of subsequent scan lines, on said photoreceptor;a rotation inducing element responsive to a position signal, said rotation inducing element causing said cylindrical mirror to rotate about said axis in response to said position signal; anda facet determining element producing a synchronization signal when a first facet of said plurality of facets is reflecting light onto said cylindrical mirror;wherein said controller receives said synchronization signal and produces said modulation signal so as to form a second latent image, comprised of a first scan line followed by a plurality of subsequent scan lines, on said photoreceptor such that the facet that produced the first scan line in said first latent image produces the first scan line in said second latent image, and wherein said controller produces said position signal such that the cylindrical mirror rotates to a position such that the second latent image is registered with said first latent image.