发明名称 In-focus state detection device
摘要 In an in-focus state detection device for determining a defocus quantity of an object lens based on a relative positional relationship of a plurality of object images, a contrast of at least one of the object images is detected before the relative positional relationship of the object images is detected, and the relative positional relationship of the object images is detected only when the contrast is larger than a predetermined level so that a determination precision and a response speed of the device are improved.
申请公布号 US4561750(A) 申请公布日期 1985.12.31
申请号 US19840630410 申请日期 1984.07.13
申请人 CANON KABUSHIKI KAISHA 发明人 MATSUMURA, SUSUMU
分类号 G02B7/28;G02B7/34;G03B3/00;(IPC1-7):G03B3/10 主分类号 G02B7/28
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