Patent ID: 8144178
Filing Date: 2012-03-27
Classification: G03G

Abstract:
1. An optical scanning apparatus comprising: a Vertical Cavity Surface Emitting Laser including a plurality of light-emitting portions that are spaced from each other in at least a sub-scanning direction, wherein the plurality of light-emitting portions emits a plurality of light beams; a first optical system including a light-condensing element that converts the plurality of light beams into a combined light beam in another state; a deflecting unit that reflects the combined light beam; and a second optical system that focuses the reflected combined light beam on a surface to be scanned, the second optical system including an imaging optical element having an optical surface with a non-arc shape in a sub-scanning cross section, wherein a principal ray of a light beam emitted from one of the plurality of light-emitting portions that is farthest from an optical axis in the sub-scanning cross section passes through a plurality of optical elements included in the first and second optical systems, the principal ray being farthest from the optical axis in the sub-scanning cross section when the principal ray passes through the optical surface of the imaging optical element, and wherein, when the focal length in the sub-scanning direction of the light-condensing element is Fcol (mm), the distance between the optical axis and the light-emitting portion that is farthest from the optical axis in the sub-scanning cross section is L