Patent attributes
A light scanning device includes: a light source; a lens which converts a light emitted from the light source to a parallel light flux; an oscillating mirror which oscillates rotationally; a mirror support body which supports the oscillating mirror and which includes a first opening; a light shield wall which is disposed between the lens and the oscillating mirror and which includes a second opening; and a diaphragm which is disposed between the light source and the light shield wall and which includes a third opening. A relation expression A1<W<B is satisfied, where W indicates a width of the second opening in any direction orthogonal to an optical axis, A1 indicates a width of the third opening in a direction corresponding to the direction of the width W of the second opening, and B indicates a width of the first opening in the direction corresponding to the direction.
