LIGHT BEAM SCANNING DEVICE

摘要

PURPOSE:To improve the image-forming characteristic on a drum, especially a scanning curvature by reducing the number of parts without increasing the scale of an optical system. CONSTITUTION:In a light beam scanning device provided with a light beam source emitting a flat light beam, a first image-forming optical system shaping and converging the light beam, a deflection means deflection-scanning by reflecting the light beam from the light beam source and a second image-forming optical system image-forming a deflected light beam being on the deflection scanning plane to a photosensitive drum surface, an incident angle is set to be small without increasing the distance between a polygon mirror 2 and the light beam source by constituting the first image-forming optical system constituted of a single lens 5 so that an incident beam axis direction to the deflection means is made at a specified angle to the deflection scanning surface and is superposed in the light beam direction of the second image-forming optical system when it is seen from the deflection scanning surface.