发明名称 |
DISTORTION CORRECTION FOR AN OVERHEAD PROJECTOR SYSTEM |
摘要 |
<p>An overhead projector which projects a distortion-free image onto a vertical screen at an oblique angle above the horizontal plane. In a first embodiment of the invention, a projection lens and mirror are displaced from the center of a transparency stage in the direction of projection and a thin, linear, incrementally-grooved prismatic sheet is positioned parallel to the stage and between the stage and a lighting means to redirect light transmitted through the stage and the transparency to the projection lens. In a second embodiment of the invention, the grooved prism is formed as an integral part of the lighting means.</p> |
申请公布号 |
EP0115900(B1) |
申请公布日期 |
1987.11.11 |
申请号 |
EP19840300005 |
申请日期 |
1984.01.03 |
申请人 |
MINNESOTA MINING AND MANUFACTURING COMPANY |
发明人 |
VANDERWERF, DENNIS F. C/O MINNESOTA MINING AND |
分类号 |
G03B21/132;(IPC1-7):G03B21/132 |
主分类号 |
G03B21/132 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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