| 摘要 |
PURPOSE:To obtain a wide range finding visual field without making a camera so large by forming a plain part as part of the diffusion area of a reticle which receives an image formed by an objective, and moving the reticle in an in-plane direction and detecting the focus state of a lens by using the signal of a part corresponding to the plain part. CONSTITUTION:Part 14a of the diffusion area of the reticle which receives the image formed by the objective 1 is made plain and luminous flux passed through the part is guided onto a photoelectric element through an image re- forming lens; and the reticle 14 is moved in the in-plane direction and signal processing is performed by using a signal corresponding to the plain part 14a in the output of the photoelectric element. Further, focus detection is performed by using the interval between images formed secondarily on photoelectric converting elements 6' and 7' through secondary image-forming lenses 4 and 5 by using pieces of luminous flux passed through different parts of the pupil of the objective 1. Consequently, the range finding visual field range is varied freely without spoiling the feature of a TTL type that the depth of field and focusing state can be confirmed on the reticle. |
