Patent ID: 8400686

Claim:
An optical scanning device comprising: a light source to project a light beam; an optical system; and a housing, including a holder, to enclose the optical system, the optical system including a liquid crystal element held by the housing via the holder, to modulate a phase of the light beam projected from the light source against a scanned surface, the liquid crystal element including: a first substantially transparent substrate having a first surface; a second substantially transparent substrate positioned in the holder and having a second surface which opposes the first surface, wherein the second surface has a total area which is larger than a total area of the first surface; the second surface further comprising an overlapping area which overlaps with the first surface, and a non-overlapping area that does not overlap with the first surface; a liquid crystal layer disposed between the first surface and the second surface in the overlapping area; a sealing member disposed between the first surface and the second surface in the overlapping area to seal the liquid crystal layer between the first and second surfaces; wherein the second substantially transparent substrate is positioned relative to the holder at the non-overlapping area.