Patent ID: 7126768

Claim:
A projection lens unit comprising: a main body extending from an image receiving end to an image emitting end; at least one lens fixed within said main body and defining an optical axis, said one lens projecting an image outward from said main body through a viewing angle having a vertex at the center of said one lens; and a hood comprising a light-shielding barrel and an annular light-shielding plate; wherein said annular light-shielding plate extends radially inward from an inner surface of said main body so as to lie along a plane orthogonal to the optical axis; wherein said light-shielding barrel extends from said light-shielding plate to said image emitting end and serves to define an outermost boundary of the viewing angle; and wherein said annular light-shielding plate has a radial dimension H, said light-shielding barrel has a length L, parallel to the optical axis, and wherein H/L is within a range from 0.74 to 0.921.