| 摘要 |
The projector device can be reduced in thickness by using a total internal reflection (TIR) prism wherein the angle formed between a line of projection of the normal vector of the total reflection plane on the surface of a digital micromirror device (DMD) and the long or short side of the DMD is set to be smaller than 45°. The TIR prism has a total reflection plane for totally reflecting illuminating light brought to incidence by an illuminating optical system to guide it to the DMD and totally transmit light optically modulated by the DMD to guide it to a projecting optical system, and this total reflection plane is so arranged relative to the DMD that the angle formed between a line of projection of its normal vector on the surface of the DMD and the long side of the DMD form an angle smaller than 45°. An incidence plane on which the illuminating light is brought to incidence by the illuminating optical system is so formed that the illuminating light brought to incidence vertically on its incidence plane, when totally reflected by the total reflection plane and emitted from an emission plane toward the DMD, be emitted at an incidence angle of 24° to the surface of the DMD in a direction at an angle of 45° to the long side of the DMD.
|
