| 摘要 |
PROBLEM TO BE SOLVED: To manufacture an aberration correcting mechanism in an optical pickup with a simple structure and easily by providing a fixing means which forms a cylindrical shape and fixing plural astigmatism generating members. SOLUTION: In the astigmatism generating part 50 provided in between a laser hologram unit 25 and a total reflection mirror 28, for example, astigmatism generating members of cylindrical lenses 26, 27 or the like are unitized integratedly with holding parts 51, 52. The holding part 51 forms a cylindrical shape and a difference in level part 52 on which the cylindrical lenses 26, 27 are to be abutted is formed at the central part of its hole and flatened parts 53 and fitting crew holes are formed in one part of the peripheral part of the part 51 so that the lenses or the like are easily attached to the part 51. Holding parts 55 are parts for fixing the lenses 26, 27 to the part 51 while pressing them to the difference in level part 52 and shapes of the parts 55 are cylindrical shapes and peripheries of them are formed so as to be engaged with the holes of the holding part 51. |
