| 摘要 |
PROBLEM TO BE SOLVED: To prevent the occurrence of excessive stress at a sticking part by expansion and shrinkage differences due to temperature or the like between a device main body and a sensor member in a focus detector. SOLUTION: In the focus detector constituted by fixing the sensor member 100 to detect the focused state of an optical system to the device main body 20, plural intermediate members 80 and 90 which are arrayed in an optical axis direction and are fixed to each other by sticking or the like, and also at least either of which holds the sensor member and at least the other of which is fixed to the device main body by the sticking or the like are interposed between the device main body and the sensor member. When the coefficient of linear expansion of the device main body is set asαB, and that of the sensor member is set asαPK, and those of plural intermediate members are orderly set asαH1,αH2, ...αHn from the intermediate member on the side of the device main body, they satisfy the inequality ofαB>αH1>=αH2>=...>=αHn>αPK. |
