Patent ID: 9558431
Date: 2017-01-31
CPC Classifications: B41J,G02B,G06K,H04N

Claim:
1. An optical scanning apparatus comprising: a light deflector that includes a rotary polygon mirror and is configured to deflect a light beam emitted from a light source; and an optical box that includes a bottom surface that supports the light deflector and a top surface that faces the bottom surface, wherein the optical box includes an aperture through which the light beam reflected by the light deflector can be emitted; wherein the top surface of the optical box is constituted by a single lid, and the top surface includes a first surface and a second surface provided at different positions in a direction from the aperture to the rotary polygon mirror, wherein the first surface is disposed closer to the rotary polygon mirror than the second surface in the direction directed from the aperture to the rotary polygon mirror, wherein the first surface is disposed closer to the rotary polygon mirror than the second surface in a rotation axis direction of the rotary polygon mirror and is disposed closer to the bottom surface than an edge portion of the light deflector positioned farthest from the bottom surface, wherein the top surface of the optical box includes a convex portion that is provided at the same position as the rotary polygon mirror in the direction from the aperture to the rotary polygon mirror in such a way as to protrude in a direction away from the bottom surface in the rotation axis direction of the rotary polygon mirror, wherein a third surface of the convex portion located at a remotest position from the bottom surface is positioned farther from the bottom surface than the first surface in the rotation axis direction of the rotary polygon mirror, and wherein a lower edge portion of the convex portion that is adjacent to the rotary polygon mirror is disposed outside a circumscribed circle of the rotary polygon mirror.