Patent ID: 6122068
Filing Date: 2000-09-19
Classification: H04N

Abstract:
An image forming apparatus for forming a color image by superimposing a plurality of color component images, comprising:scanning means for generating a light beam modulated based on an image signal corresponding to each of said color component images and for scanning the generated light beam in a main scan direction of said color image by reflecting the generated light beam with a rotary polyhedron;an image carrier moving in a subscan direction of said color image so as to carry each of said color component images;first generating means for generating a first detecting signal synchronous with a timing of rotation of said rotary polyhedron;second generating means for generating a second detecting signal indicating a timing of movement of said image carrier; andcontrol means for controlling a start position of writing each of said color component images to reduce variations in registration of the start position by adjusting a speed of movement of the image carrier for each color component image responsive to a comparison of said first detecting signal with said second detecting signal.