Patent ID: 7131738

Claim:
A light processing module for a projection display device, comprising: a color separator; a light modulator including a liquid crystal panel for modulating light received from said color separator; a wave plate disposed between said color separator and said light modulator, and having fast and slow axes; and a dust protection member including a base frame having a component mounting side that is formed with a first frame opening, said color separator being mounted in said base frame, said light modulator being mounted spacedly on said component mounting side, a first frame element disposed between said light modulator and said component mounting side of said base frame, and formed with a second frame opening that is registered with said first frame opening and that has said liquid crystal panel received therein, said first frame element further having an annular first coupling flange that surrounds said second frame opening and that extends toward said component mounting side of said base frame, and a second frame element disposed between said first frame element and said component mounting side of said base frame, and formed with a third frame opening that is registered with said first and second frame openings and that has said wave plate received therein, said second frame element being further formed with an annular second coupling flange that surrounds said third frame opening and that is coupled coaxially and rotatably to said first coupling flange, said first and second frame elements cooperating with said light modulator and said wave plate to form a dustproof chamber between said liquid crystal panel and said wave plate, said second frame element being rotatable relative to said first frame element and said base frame to permit adjustment of positions of said fast and slow axes of said wave plate relative to said color separator.