Patent ID: 7661829

Claim:
A projection display apparatus comprising: a light valve; a light source that emits light to said light valve; an integrator lens that is disposed on an optical path of said light propagating from said light source to said light valve and that makes uniform an illuminance distribution of the light from said light source; and a shutter mechanism that is disposed on said optical path and that controls an amount of said light that illuminates said light valve, said shutter mechanism comprising a pair of light-blocking members having cuts formed in their respective protruding sides to regulate passage of said light, said pair of light-blocking members being moved straight to protrude/retract on said optical path, approximately perpendicularly to said optical path from both sides of said optical path, so as to control the amount of said light according to an extent of their protrusion on said optical path, wherein a largest amount of passage light appears in two portions of an upper half of said integrator lens and a lower half of said integrator lens, in each said light-blocking member, said cut includes a cut that regulates passage of said light through said upper half of said integrator lens so as not to block said largest amount of passage light and a cut that regulates passage of said light through said lower half of said integrator lens so as not to block said largest amount of passage light, and in a full-closed state of said pair of light-blocking members, each of said cuts forms a pair of openings that allows light transmission only through said largest amount of passage light.