Magneto-optical head

Abstract

Abstract PURPOSE:To detect a reproducing signal by means of a miniaturized and inexpensive polarizing beam splitter by constituting an analyzer of the polarizing beam splitter consisting of a parallelogram prism having full reflection faces parallel with a polarizing film held between the full reflection faces and a transparent plate. CONSTITUTION:The analyzer is constituted of the polarizing beam splitter 16 consisting of the polarizing film 16a for transmitting P-polarized light 15a and reflecting S-polarized light 15b, the parallelogram 16b having full reflection faces parallel with the film 16a held between them and the transparent plate 16c. On the other hand, a photodetector 17 is obtained by unitedly forming a light receiving area 17a for receiving the P-polarized light 15a, 4-divided light receiving areas 17b-17e for receiving the S-polarized light 15b and an unused light receiving area 17f on the same plane. The polarizing beam splitter 16 and the photodetector 17 are arranged around the optical axis of converged light beams 15 with a 45 deg. rotational angle difference. Consequently, the polarizing face made incident upon the analyzer can be rotated by 45 deg. while keeping the optical system at a miniaturized constitution and the miniaturized beam splitter 16 can be arranged immediately before the photodetector 17.

Inventors

• 👤 Yoshihiro Katase
• 👤 Yasuo Otsuka
• 👤 Toru Sasaki

Bibliographic Details