发明名称 Exposure control device
摘要 An exposure control device having a light measuring area setting circuit which sets a light measuring area on an image sensing plane, a discriminating circuit which discriminates from each other varied states of the image sensing plane through video signal parts corresponding to the inside and the outside of the light measuring area and an exposure compensating circuit which compensates the state of exposure to light is arranged to shift the set position of the light measuring area to trace an object's image at least when the exposure compensating circuit is in operation. The operating modes of the device includes a first light measuring mode in which a quantity of light is measured on the basis of the average video signal level of the whole image sensing plane, a second light measuring mode in which the light quantity is measured with weight attached to a video signal part obtained from the inside of the light measuring area, and a third light measuring mode in which the light quantity is measured with weight attached to the video signal of the light measuring area by shifting the light measuring area to trace the object. The three light measuring modes are adaptively switched from one over to another.
申请公布号 US6570620(B1) 申请公布日期 2003.05.27
申请号 US19950483561 申请日期 1995.06.06
申请人 CANON KABUSHIKI KAISHA 发明人 YOSHIMURA KATSUJI;KANEDA KITAHIRO;HOMMA HIDEO;YAMADA KUNIHIKO;SUDA HIROFUMI;FUJIWARA AKIHIRO
分类号 H04N5/235;(IPC1-7):G03B7/00 主分类号 H04N5/235
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