Patent ID: 8957928
Filing Date: 2015-02-17
Classification: B41J,G02B

Abstract:
1. An image forming apparatus, comprising: a photoconductor; a charger to a multi-beam scanning unit including: a vertical cavity surface emitting laser as a light source having a plurality of light emitting elements two-dimensionally arrayed in a main scanning direction and a sub-scanning direction perpendicular to the main scanning direction and arranged so that an interval between light emitting elements adjacently disposed at a center portion of the scanning unit in the sub-scanning direction is set narrower than an interval between other light emitting elements adjacently disposed at other portions of the scanning unit in the sub-scanning direction; a deflecting element to deflect a plurality of light beams emitted from each of the plurality of light emitting elements to scan and expose the charged surface of the photoconductor to write a two-dimensional electrostatic latent image on the photoconductor by conducting an interlace scan on the photoconductor in the main scanning direction and the sub-scanning direction perpendicular to the main scanning direction while the surface of photoconductor is moving in the sub-scanning direction; and a light intensity adjustment unit to adjust a light intensity of at least one of the light emitting elements adjacently disposed at the center portion in the sub-scanning direction relative to a light intensity of other light emitting elements adjacently disposed at other portions in the sub-scanning direction, and when only one of the light emitting elements adjacently disposed at the center portion in the sub-scanning direction is activated to emit light in a single scanning of a scan line the light intensity adjustment unit sets a light intensity of the one of the light emitting elements adjacently disposed at the center portion in the sub-scanning direction that is activated to be the same as a light intensity of other light emitting elements disposed at other portions in the sub-scanning direction; a development unit to develop the electrostatic latent image, using a development agent, formed on the surface of the photoconductor; and a transfer unit to transfer the image developed on the surface of the photoconductor by the development unit to a transfer medium, wherein the light beams are emitted from a given number of the light emitting elements of the light source to write an image of one pixel while setting a writing resolution level that is higher than a raster resolution level, and wherein the light intensity adjustment unit includes a flip flop circuit and a digital/analog converter.