| 摘要 |
PURPOSE:To enable high-accuracy focus detection at all times without reference to the kind of a photographic lens by providing two focus detection systems which have different base line lengths in a camera main body and using the two focus detection systems distinctively corresponding to the kind of the photographic lens mounted on the camera main body. CONSTITUTION:The lateral opening part 17a of a visual field mask 17, the straight line L14cd which connect the lens surface peak points of the couple of lenses 14c and 14d of a secondary optical system 14, and the segment L15cd in the array direction of the couple of photodetecting element array 15c and 15d of a photodetecting means 15 are nearly parallel to one another. Then those respective elements constitute a focus detection system at the time of the use of a mirror system. Similarly, an opening part 17b, a straight line L14ab, and a segment L15ab in the array direction are also nearly parallel and those respective elements constitute a focus detection system at the time of the use of a refraction type lens. The focus detection signals of those two focus detection systems are selected properly and used to enable the focus detection with invariably excellent accuracy without reference to the kind of the photographic lens. |
