| 摘要 |
PURPOSE:To constitute an optical head reproducing information from a recording medium such as a magneto-optical disk to be thin and to eliminate the need of providing a different 1/2 wavelength board and the like. CONSTITUTION:In light emitted from a semiconductor laser 14, the S-wave component is much reflected on a polarized layer 12, and it is converged on the recording medium M. Return light from the recording medium M passes through the polarized layer 12, and a polarized surface is rotated on a 1/2 wavelength layer 13. A light-receiving member 17 receives the S-wave component passing through a polarized layer 16. A P-wave component reflected on the polarized layer 16 passes through the 1/2 wavelength layer, is reflected on the polarized layer 12 and it returns through the 1/2 wavelength layer. The polarized layer 16 fetches the S-wave component and a light-receiving member 18 receives it. The light-receiving output of the light-receiving member 18 is amplified by a gain twice as much as the light-receiving output of the light-receiving member 17, and a differential amplifier 21 obtains a voltage difference. Thus, an MO signal can be reproduced. |
