| 摘要 |
PURPOSE:To reduce the occurrence of a focus detection failure state and to enable early focus detection by setting the 1st and the 2nd focus detection zones, and switching one zone where it is judged that the focus detection can not be performed to the other zone cyclically and automatically while the judgement is made and then carrying out the focus detection. CONSTITUTION:The 1st and the 2nd focus detection areas I and II are set on a CCD line sensor 33 corresponding to the 1st focus detection area positioned at the center part of a photographic picture plane and the 2nd wider focus detection area including the 1st focus detection area. A focus detection control means starts the focus detection at the 1st focus detection zone I and when the focus detection becomes impossible because of no subject or plural subjects which differ in distance from a camera, the current focus detection zone is switched automatically and cyclically to the other focus detection zone to carry on the focus detection. Then, the focus detection becomes possible in the 1st or the 2nd focus detection zone, the focus detection is repeated in the focus detection zone. Consequently, the focus detection is performed in either focus detection zone and the focus detection failure state is eliminated at its early stage. |
