| 摘要 |
PURPOSE:To miniaturize the titled device, to reduce the weight of the device and to efficiently perform recording and reproduction, by diffracting reflected light whose polarizing plane is rotated by a micro angle on an information recording plane at respective grating area of a polarizing diffraction grating, and detecting diffracted light to be transmitted on a substrate by a detecting element. CONSTITUTION:A divergent beam of light emitted from a semiconductor laser 21 passes through the grating coupler 30 of a waveguide element 24 and an objective lens 25, and is made incident on the information recording plane of a magneto-optical disk 22. At the time of being reflected on the information recording plane of the disk 22, the polarizing plane of the incident light is rotated by the micro angle by a Kerr effect or a Faraday effect. The reflected light passes through the lens 25 again, and is made incident on the coupler 30, and is diffracted and coupled to a waveguide by the diffractive operations of the grating areas 30a and 30b, and are received at optical detectors 33 and 34 respectively. And an output in which the sum of the outputs of detecting bodies 33a, 33b, and 33c of the detector 33 is subtracted from the output of the detector 34 is increased by the rotation of the polarized angle of the reflected light by a prescribed angle for information recorded on the disk 22.
|
