| 摘要 |
PROBLEM TO BE SOLVED: To surely fix a half mirror. SOLUTION: A pair of right and left concave grooves 11 which communicate to the opening part 2a of an optical pass hole 2 are formed on the both sides of an inner faces 5c, among four inner side faces 5a to 5d of the optical pass hole 2, which are placed opposite to the bottom side end fringe 3c of the half mirror 3, the both side fringe parts of the fixing fixture main body 12a of a leaf spring fixing fixture 12 are inserted into both of the concave grooves 11, a pair of right and left pressing plate parts 12b is provided which is extended from both fringe parts of the fixing fixture main body 12a and elastically abut on the surface of the half mirror 3, a pair of right and left engaging lug 12c is provided which engages with the inner side face 5c by being bent from both side fringe parts of the fixing fixture main body 12a in the direction opposite to the extended direction of the pressing plate parts 12b, and a hooking piece part 12d is provided which is bent from the central part of the fixing fixture main body 12a in the same direction as that of the engaging lug 12c and extended to the peripheral fringe of the opening part 2a of the optical pass hole 2 for light beam. |
