| 摘要 |
PURPOSE:To improve the discrimination accuracy of signal reading by providing a semiconductor laser element, with the joining surface of the element being inclined about 45 deg. against the relatively moving direction of an information record train, and, at the same time, providing an apodization filter. CONSTITUTION:A semiconductor laser element 11 is provided, with its joining surface 11a being inclined at about 45 deg. against the relatively moving direction 21a of an information record train, and, at the same time, an apodization filter 12 is provided on the optical axis of the laser light between the element 11 and information record train so as to lower the intensity of the component almost perpendicular to the relatively moving direction of the information record train of the laser light. When the semiconductor laser element is arranged in such way, the focusing position at which the discrimination accuracy of signal reading becomes the best and another focusing position at which track detecting signals become the maximum can be made coincident with each other. Because of the apodization filter, moreover, the spot diameter of the laser light can be enlarged. Thus an optical information recorder whose discrimination accuracy of signal reading is improved and which is hardly influenced from the aberration to the inclination of the light projecting surface against the optical axis can be obtained. |
