| 摘要 |
PURPOSE:To provide an optical pickup device having high efficiency of utilization of a laser light source. CONSTITUTION:An aperture 3a for limiting the passage of light 2 radiated from a semiconductor laser light source 1 is made elliptical. The major axial direction of the aperture 3a is made parallel to the horizontal direction of the light source 1 and the angle of estimate of the aperture 3a to the light source 1 is made large while keeping a converged light spot 9 circular. |
