Patent ID: 7215348

Claim:
An image forming apparatus in which a plurality of lines each having a plurality of light emitting elements are arranged to have rows in a sub scanning direction of an image carrier so that light emitting elements are arranged in a matrix in a plane, wherein pixels on said image carrier are exposed by the light emitting elements aligned in one line and exposed again by the light emitting elements aligned in the next line after the movement of said image carrier, and in the same manner, said pixels are sequentially exposed by the light emitting elements on another line after the movement of said image carrier so as to achieve multiple exposure of the pixels, said image forming apparatus comprising: control means by which said light emitting elements on respective lines for exposing same pixels are driven by a TFT so as to emit a same amount of light, so that the pixels can be exposed according to gradation output formed by said control means; and storage means for storing image data formed by said control means and outputting said image data to said light emitting elements, wherein said storage means is composed of multiple shift resistors which are arranged to correspond to the lines of the light emitting elements arranged in the sub scanning direction, respectively, and are designed to transport image data, hold the image data, and output the image data to the light emitting elements, wherein the image data supply to the shift resistor on a first line is transmitted in the main scanning direction and is also transmitted in the sub scanning direction to the shift resistor on a next line, and, in this manner, the image data is sequentially transmitted in the sub scanning direction to the shift resistors on the respective lines so that the image data is outputted to the light emitting elements on each of lines corresponding to the shift resistors, respectively.