发明授权
- 专利标题: Backlighting detecting device
- 专利标题(中): 背光检测装置
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申请号: US345444申请日: 1989-05-01
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公开(公告)号: US4969005A公开(公告)日: 1990-11-06
- 发明人: Tatsuyuki Tokunaga
- 申请人: Tatsuyuki Tokunaga
- 申请人地址: JPX Tokyo
- 专利权人: Canon Kabushiki Kaisha
- 当前专利权人: Canon Kabushiki Kaisha
- 当前专利权人地址: JPX Tokyo
- 优先权: JPX63-111332 19880506
- 主分类号: G01J1/44
- IPC分类号: G01J1/44 ; G03B7/091 ; G03B7/28
摘要:
A device for detecting a backlighting condition comprising a light meter of which the image receiving surface is divided into a central area, an intermediate area and a marginal area, and a circuit for discriminating between true and false backlighting conditions in such a way that when the luminance of the marginal area is greater than that of the intermediate area by more than a predetermined value and when the luminance of the intermediate area is greater than that of the central area, the backlighting condition in question is taken as a true one.
公开/授权文献
- US6052282A Electronic equipment 公开/授权日:2000-04-18
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