PURPOSE: To suppress the rotation of an objective lens holder around a central axis and to stabilize an operation by adding another elastic wire rod to link a supporting base and the objective lens holder, and arranging it in central axis shape of another elastic wire rod comprising a link arm.

CONSTITUTION: A fifth elastic wire rod 10 is arranged at the position of the central axis line of four elastic wire rods 3 comprising a parallelogram link arm by linking a supporting board 2 fixed on the supportin base 1 and the holder 5 holding an objective lens 4. The wire rod 10 is fixed by fitting its one end in a hole 2a on the supporting board 2, and the other end in a hole 5a on the holder 5, respectively. The wire rod 10 is mounted between the supporting board 2 and the holder 5 so as to be set in parallel with another wire rod 3. In such a way, it is possible to prevent the inclination of the optical axis of the objective lens from being generated by suppressing the rotation of the holder 5 around the axial line, and to stably perform the operation.