Patent ID: 8400488
Filing Date: 2013-03-19
Classification: B41J,G02B,G06K

Abstract:
1. An optical scanning apparatus for forming an electrostatic latent image on a photosensitive member, comprising: a light emission unit configured to emit plural light beams including first and second light beams and arranged to form images of light at different positions in a rotation direction of the photosensitive member; a deflection unit configured to deflect the light beams emitted from said light emission unit such that the light beams move in a predetermined direction, wherein the photosensitive member is positioned on movement paths of the light beams deflected by said deflection unit; a first detection unit disposed on the movement paths of the light beams and configured to detect each of the first and second light beams emitted from said light emission unit before the light beams move along an image region on the photosensitive member; a second detection unit disposed on the movement paths of the light beams and configured to detect each of the first and second light beams emitted from said light emission unit after the light beams have moved along the image region on the photosensitive member; a measurement unit configured to measure a first time period from when said first detection unit detects the first light beam to when said second detection unit detects the first light beam and measure a second time period from when said first detection unit detects the second light beam to when said second detection unit detects the second light beam; and a position adjustment unit configured to adjust relative positions of said first and second detection units such as to make the first time period equal to a product of the second time period and a correction coefficient set based on a wavelength difference between the first and second light beams.