| 摘要 |
PROBLEM TO BE SOLVED: To provide a mechanism for regulating the position in the rotating direction of optical parts of an optical pickup which is simple in constitution, can be inexpensively manufactured and is yet capable of regulating the posture with high accuracy and ensuring the maintenance of the posture after the regulation. SOLUTION: This mechanism has a base 10 which mounts a diffraction granting 20 in a state movable to a rotating direction A, an internal thread section 12 which is formed at the base 10 so as to extend in a rectilinear direction C parallel with the tangent with respect to the rotating direction of the diffraction granting 20, external threads 30 which are screwed into the internal thread section 12, an optical parts side projecting part 22 which is so formed as to project into the peripheral surface of the diffraction grating 20 and a threads side recessed part 32 which is formed to recess on the peripheral surface of the external threads 30. The external threads 30 are screwed into or out of the internal thread section 12 and is thus moved in the rectilinear direction C, by which the rotation of the diffraction grating 20 in the direction A through the threads side recessed part 32 and the optical parts side projecting part 22 is made possible. |
