| 摘要 |
PROBLEM TO BE SOLVED: To provide the focus detecting device which can be assembled without requiring adhesion or any extra component. SOLUTION: This detecting device is equipped with a field lens 2 which is arranged nearby the expected focal plane of an objective, a holder 1 which holds the field lens 2 and is equipped with a projection at its outer periphery, and a visual field mask 4 which is composed of a thin plate member and arranged in front of the field lens 2 and forms a focus detection visual field frame. The visual field mask 4 has an arm part 4d which is bent almost at right angles from the surface forming the focus detection visual field frame and equipped with a hole part, and a hole part 4d1 formed in the arm part 4a and a projection 1d provided to the holder 1 engage each other to fix a visual field mask 4 to the holder 1. |
