| 摘要 |
PROBLEM TO BE SOLVED: To prevent the increase of the size of a shutter unit by arranging a photointerrupter.SOLUTION: A focal plane shutter comprises: a shutter base plate to which a front blade driving member rotated integrally with a front blade group and a rear blade driving member rotated integrally with a rear blade group are rotatably attached; a first electromagnet capable of holding the front blade driving member, when photographing is started; a second electromagnet capable of holding the rear blade driving member, when photographing is started; a front blade cam gear charging the front blade driving member; a rear blade cam gear charging the rear blade driving member; a first optical detection member detecting the rotational position of the front blade driving member; and a second optical detection member detecting the rotational position of the rear blade driving member. At least one of the first and second optical detection members is arranged between the front blade driving member and the rear blade driving member and between a line for connecting the first and second electromagnets and a line for connecting the rotation centers of the front blade cam gear and the rear cam gear. |
