| 摘要 |
PURPOSE:To obtain the optical head device which can be manufactured with high accuracy by processing and forming one surface of the lens to constitute the converging means in a rugged shape, and providing the diffracting lattice to diffract the reflecting light from the recording media and guide it to the photodetecting device. CONSTITUTION:The luminous flux from a semiconductor laser 11 is reflected by a reflecting surface 31 of a prism 30, and made parallel by a collimator lens 32. The collimator lens 32 has the aspheric surface on one side and the surface where a rugged diffracting lattice 35 is processed, and the surface, where the diffracting lattice is processed, is junctioned with a parallel plate 34 by an adhesive layer 33 of the refraction factor almost equal to the lens. When the collimator lens 32 is processed by the injection method or the compression method, the chamfer occurs at the surface of both sides, the harmful bending will no occur and stable processing can be executed. The luminous flux made parallel by the collimator lens 32 transmits the adhesive layer 33 and the parallel plate 34, and is converged through a substrate 19 to an information recording carrier 20 by an objective lens 18. thus, the device with a simple constitution can be manufactured with high accuracy. |
