| 发明名称 |
Light-blocking transparency assembly |
| 摘要 |
A sheet of imageable film for use in an overhead projector is provided with at least one, and preferably two, opaque flaps attached in a foldable manner to the film so that the flaps may be unfolded to prevent unwanted light from shining past the edges of the transparency.
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| 申请公布号 |
US5319400(A) |
申请公布日期 |
1994.06.07 |
| 申请号 |
US19930001301 |
申请日期 |
1993.01.06 |
| 申请人 |
MINNESOTA MINING AND MANUFACTURING COMPANY |
发明人 |
HERBERT, ALAN J.;EVANS, DWIGHT L.;RUSSELL, TERRANCE J. |
| 分类号 |
G03B21/32;G03B21/132;G03G7/00;(IPC1-7):G03B21/30 |
主分类号 |
G03B21/32 |
| 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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