| 摘要 |
PROBLEM TO BE SOLVED: To provide an objective lens with which the sticking of the objective lens to an objective lens fixing holder to regulate the comatic aberration and tilt of the lens or the regulating of the optical axis tilt of the laser beam of an optical pickup device may be inexpensively and rapidly realized by an autocollimator, etc. SOLUTION: A mirror finished surface flat surface 13a which is a reference plane to assure the perpendicularity with high accuracy to the optical axis 11 of the objective lens 1 is formed on the outer peripheral part of an upper aspherical surface 13 at a width, at which the reflected light from this mirror finished surface flat surface may be easily obtained, when the flat surface is irradiated with parallel light beams, by which the sticking of the objective lens to the objective lens fixing holder to regulate the comatic aberration and tilt of the lens or the regulating of the optical axis tilt of the laser beam of the optical pickup device with the autocollimator may be easily and rapidly realized. |
