发明授权
- 专利标题: Optical overhead projector for electronic images
- 专利标题(中): 用于电子图像的光学高架投影仪
-
申请号: US8503申请日: 1993-01-25
-
公开(公告)号: US5260730A公开(公告)日: 1993-11-09
- 发明人: Richard E. Williams , Ernest F. Clough , Mark L. Daniel
- 申请人: Richard E. Williams , Ernest F. Clough , Mark L. Daniel
- 申请人地址: FL Lake Mary
- 专利权人: Numa Corporation
- 当前专利权人: Numa Corporation
- 当前专利权人地址: FL Lake Mary
- 主分类号: G02F1/133
- IPC分类号: G02F1/133 ; G02F1/13357 ; G03B21/132 ; G03B21/00
摘要:
A relatively small liquid-crystal display (LCD) device located well above the fresnel stage of an overhead projector produces large, sharp images with full color and motion. A focus-correcting lens moves with the overhead projector's optical head to maintain proper projection-focus and magnification. Spectrally-selective filters are interposed between the LCD device and fresnel stage to avoid LCD deterioration. A fan-actuated shutter or electrically-actuated shutter optionally provide still further protection. Optical collimation methods are employed to attain a large depth-of-field and image brightness.
公开/授权文献
- US6082761A Side airbag device 公开/授权日:2000-07-04
信息查询