| 摘要 |
PROBLEM TO BE SOLVED: To make it easy to adjust an optical head by forming a diffusion angle converting means, a 1st separating means, and a 2nd separating means integrally in an optical element. SOLUTION: The laser light emitted by a laser diode 21 is made incident on a magnetooptical disk 42 through a collimator lens 31, a total reflecting mirror 32, a beam splitter 33, and an objective lens 41. Light which is transmitted through the beam splitter 33 as to the laser light reflected by the magnetooptical disk 41 is transmitted through a 1/2 wavelength plate 39 and partially reflected by the beam splitter 34 and is made incident on a photodetector 37. The light transmitted through the beam splitter 34 is reflected by the total reflecting mirror 35 and made incident on a photodetector 38. An RF signal corresponding to a signal recorded on the magnetooptical disk 42 is generated from the difference between the outputs of the photodetectors 37 and 38. The collimator lens 31, beam splitters 33 and 34, 1/2 wavelength plate 39, photodetectors 36 to 38 are united at an alignment part 30. |
