Patent ID: 7839552
Filing Date: 2010-11-23
Classification: G02B,H04N

Abstract:
1. An optical scanning device, comprising: a scanning unit scanning a scanning surface with light from a light source unit in a first direction and a second direction orthogonal to the first direction, the scanning unit comprising a deflection surface which sine-wave-drives in at least the first direction, and an optical unit guiding the light with which scanning is performed by the scanning unit onto the scanning surface, wherein the optical unit has an optical surface, and each of shapes of the optical surface in first and second cross sections is a shape in which an optical power to diverge a light in a peripheral portion is stronger than that in a central portion, and in which a surface curvature radius in the peripheral portion is smaller than a surface curvature radius in the central portion, wherein the first cross section and the second cross section are parallel to the first direction, the first cross section is parallel to the second cross section, the first cross section and the second cross section are located at different locations in the second direction within the optical surface, the first cross section is located at a fixed distance from a first edge of the optical surface in the second direction, the second cross section is located at the fixed distance from a second edge of the optical surface in the second direction, and the second edge is different than the first edge, and wherein the shapes of the optical surface in the first and second cross sections are different from each other.