发明名称 |
Light integrating circuit for use in a light measuring device which is accurate for both low and high light values |
摘要 |
A light measuring circuit including a light sensing device for sensing light and producing a signal representative of the light sensed, a compressing circuit for compressing the signal, a capacitor having one terminal connected to a predetermined voltage, a charging circuit responsive to the compressing circuit for charging the capacitor, a detecting circuit for responding to the voltage level of the capacitor, a switch for shorting the capacitor when closed for initiating charge of the capacitor by opening, and a delay circuit coupled to one of the charging circuits and the switch for delaying the onset of charge of the capacitor.
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申请公布号 |
US4808811(A) |
申请公布日期 |
1989.02.28 |
申请号 |
US19870107879 |
申请日期 |
1987.10.09 |
申请人 |
CANON KABUSHIKI KAISHA |
发明人 |
KUMAKURA, TOSIYUKI;KATAOKA, HIROYUKI;OHMORI, KOUICHI |
分类号 |
G03B7/08;G03B7/16;(IPC1-7):G01J1/00 |
主分类号 |
G03B7/08 |
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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