发明名称 Focus detection method and focus detection apparatus
摘要 A focus detection apparatus includes a focusing lens group, and a controller. The controller establishes a first predetermined number and a first criterial value if a maximum contrast value and/or minimum contrast value is outside a predetermined range, and a second predetermined number and second criterial value if the maximum and minimum contrast values are within the predetermined range; compares contrast values detected at adjacent positions to determine whether the contrast value of the object image increases once and subsequently decreases by the first or second predetermined number of times; detects a maximum contrast value if the contrast value of the object image increases once and subsequently decreases by the first or second predetermined number of times; determines a difference between the maximum contrast value and a detected contrast value; and selects the maximum contrast value if the difference exceeds the first/second criterial value.
申请公布号 US7502065(B2) 申请公布日期 2009.03.10
申请号 US20050152065 申请日期 2005.06.15
申请人 HOYA CORPORATION 发明人 NAKAHARA NAOTO
分类号 H04N5/232 主分类号 H04N5/232
代理机构 代理人
主权项
地址