| 摘要 |
PURPOSE: To increase available recording density width by projecting light beams reflected from an optical storage medium again and mounting at least re-projection lens forming the image of a light spot on the recording medium. CONSTITUTION: A photodetector 22 contains a re-projection device 24 projecting reflected light beams onto a plate 26 with a pinhole aperture 28 again. The re-projection lens 24 preferably has a focal distance longer than the focal distance of an objective 18. Accordingly, a re-projeced light spot on the plate 26 has a change larger than a light spot on a magneto-optic disk in glass distribution by the principle of microscope magnification. That is, the light spot on the plate 26 is formed in an image, in which the light spot formed on the magneto-optic disk 20 is magnified. |
