Patent ID: 7256918

Claim:
A method of determining an arrangement of an optical scanning device provided with a rotary polygon mirror rotating in a downstream direction and having a plurality of reflective faces, the method comprising steps of: selecting either predominantly S-polarized light or predominantly P-polarized light as light to be received on one of the reflective faces and to be reflected and deflected along a deflection trajectory in accordance with a rotary action of the polygon mirror; and positioning a photo emitter, which emits the light, such that if the predominantly S-polarized light is selected, the light is received on the one of the reflective faces from a location in the downstream direction relative to the deflection trajectory, and, if the predominantly P-polarized light is selected, the light is received on the one of the reflective faces from a location in an upstream direction relative to the deflection trajectory, wherein the upstream direction is opposite to the downstream direction.