LENS SHIFTER

PURPOSE:To move a lens shifting frame smoothly with high accuracy by making the deviation in thread pitch between a couple of rack parts of a connecting plate less than the thread pitch of a screw and engaging and clamping the both. CONSTITUTION:The connecting body 6 fixed to part of the lens shifting frame 1 has the couple of rack parts 7a and 7b which are arranged opposite each other at a specific interval. The deviation in thread pitch between the couple of opposite rack parts 7a and 7b is set less than the thread pitch 1/2 pitch of the screw 5. A motor 4 is rotated and the screw provided to its output shaft 4a is rotated to move the frame 1 along guide rods 2 and 3 while the engagement state is maintained by the rack parts 7a and 7b. At this time, the rack parts are given elasticity by setting the thread pitches of the screw 5 and rack parts 7a and 7b as mentioned above to effectively preclude axial play.