Patent ID: 8289600

Claim:
An optical scanning device comprising: a plurality of light beam irradiation devices irradiating a light beam; a deflector deflecting the plural light beams irradiated from the light beam irradiation devices into substantially opposite directions; scanning optical systems disposed substantially in an opposing manner relative to the deflector as a center, the scanning optical systems each scanning a scanning surface using the light beam deflected by the deflector; and first and second light screening materials, each comprising a first side and a second side, in which the first side screens a flare light emitted from a first scanning lens in the scanning optical system so as to prevent the flare light from being projected onto a second scanning lens in the substantially opposite scanning optical system, wherein the first light screening material in which the first side of the light screening material screens the flare light emitted from the first scanning lens is disposed more closely to the second scanning lens than to the first scanning lens, the first light screening material screening the flare light emitted from the first scanning lens is disposed so as not to prevent a flare light emitted from the second scanning lens from being projected onto the first scanning lens, the second side of the first light screening material does not screen a flare light emitted from the first scanning lens and does not screen a flare light emitted from the second scanning lens, and when the second light screening material extends along a line which connects a central axis of the deflector to a corner where deflection surfaces of the deflector are brought into contact, the first light screening material is arranged so as not to extend along a line which connects the central axis of the deflector to a corner where deflection surfaces of the deflector are brought into contact.