Patent ID: 6452709
Filing Date: 2002-09-17
Classification: B41J,G02B,H04N

Abstract:
An optical exposure unit comprising:a light source; forwardly deflecting optical set including a first lens for providing a light beam from said light source with a predetermined characteristic, and a second lens for converging said light beam from said first lens in a first direction; a deflector for deflecting the light beam output from said second lens in a second direction perpendicular to the first direction, said deflector including a reflection surface which is formed to be rotatable about a rotation axis extending in a direction parallel to the first direction as a center of rotation; and an imager, including at least one lens, for imaging the light beam deflected at an equal speed by said deflector at a predetermined position, wherein the second lens comprises a one-sided cylinder lens formed of glass, and a double-sided cylinder lens formed of a material substantially equivalent to a material of said imager, and the double-sided cylinder lens corrects shifting of an imaging surface of the imager in the first direction, which results from variation of a refractive index of the imager which is caused by a temperature change.