Patent ID: 9069154
Filing Date: 2015-06-30
Classification: G02B

Abstract:
1. A projection lens that: projects image information displayed at a reduction-side conjugate position onto a magnification-side conjugate position; satisfies conditional expressions (1) and (2); and satisfies conditional expressions (3) and (4) when a single lens which includes a surface having the smallest effective beam diameter or a cemented lens is designated as a reference lens, a system substantially consisting of lenses disposed closer to a magnification-side than the reference lens is designated as a front group, and a system substantially consisting of lenses disposed closer to a reduction side than the reference lens is designated as a rear group: where ω: a half angle of view of the projection lens, βP: a pupil magnification (a reduction-side pupil diameter/a magnification-side pupil diameter), fM: the focal length of the reference lens, fF is the focal length of the front group, and fR is the focal length of the rear group.