Patent attributes
An optical scanning device, which comprises a light source unit, a scanning unit for scanning a scanning surface with a light from the light source unit in a first direction and a second direction orthogonal to the first direction, and an optical unit for guiding the scanning light onto the scanning surface. The scanning unit has a deflection surface which sine-wave-drives in the first direction. The optical unit has an optical surface whose arbitrary cross section in the first direction has a shape where a second order derivative of the function representing a shape of the cross section changes so as to diverge a light stronger as toward the periphery from the center. And the optical surface is configured by arranging the shape of each cross section in the first direction in the second direction.
