发明名称 Light measuring circuit
摘要 A light measuring element which is provided with a pulse signal generator for generating pulse signals the duty ratio of which varies in accordance with a coefficient related to the exposure for photographing, a switching element which is driven by the output pulse signals from the pulse signal generator, and a light integrating circuit which includes a photo detector and an integrating capacitor and provides the voltage across the integrating capacitor as a light measure output. The light integrating circuit performs an intermittent light integrating operation by the action of the switching element. The integration period of the light integrating circuit is varied by varying the duty ratio of drive signals to the switching element which are supplied from a pulse signal generator, which duty ratio varies with a coefficient related to the proper exposure for photographing.
申请公布号 US4400087(A) 申请公布日期 1983.08.23
申请号 US19810262895 申请日期 1981.05.12
申请人 NAKAYAMA, YASUO 发明人 NAKAYAMA, YASUO
分类号 G03B7/081;G01J1/46;G03B7/083;G03B15/05;H05B41/32;(IPC1-7):G01J1/46;H05B41/14 主分类号 G03B7/081
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