发明申请
- 专利标题: Prism for high contrast projection
- 专利标题(中): 棱镜用于高对比度投影
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申请号: US10335342申请日: 2002-12-31
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公开(公告)号: US20030151834A1公开(公告)日: 2003-08-14
- 发明人: Steven M. Penn
- 主分类号: G02B005/04
- IPC分类号: G02B005/04
摘要:
Prism elements having TIR surfaces placed in close proximity to the active area of a SLM device 302 to separate unwanted off-state 324 and/or flat-state 326 light from the projection ON-light bundle 322. The TIR critical angle of these prisms is selected to affect either the off-state light or additionally, any portion of flat-state light reflected from the SLM. These TIR surfaces are placed to immediately reflect the unwanted light as it comes off the SLM, thereby preventing the contamination of light along the projection path, which tends to degrade the system contrast. To further improve the optical performance of the system, these TIR prisms can be attached directly to the SLM package 300, completely eliminating the package window. Also, these TIR prism can be coupled to DMDs having asymmetric mirrors, which tilt through a larger angle for the ON-light to provide high etendue and lumen output, but through near-zero degrees for the OFF-light, thereby improving the separation of any unwanted light from the off/flat states.
公开/授权文献
- US06959990B2 Prism for high contrast projection 公开/授权日:2005-11-01
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