| 摘要 |
PURPOSE:To execute stable focus and tracking operations, when a recording medium is inclined, by leading a reflected light from an information recording medium, into a first and a second waveguides formed on the both faces of a transparent substrate. CONSTITUTION:On the upper and lower faces of a glass substrate 1 of an optical information processor, optical waveguide layers 2, 3 of prescribed thickness are formed, respectively, and also, clad layers 5, 6 are formed. Moreover, on the upper and lower faces, focus grating couplers 7, 8 for exciting a TE mode are formed, respectively. On this coupler 8, parallel rays from a semiconductor laser 10 are made incident, and converged to a magnetic disk 14 through the coupler 7. Also, a reflected light from the disk 14 is brought to waveguide as a waveguide light to the layers 2, 3 by the couplers 7, 8, respectively. The light intensity of this waveguide light is detected by 3-split detectors 20, 21, and focusing and tracking errors are detected by detectors 24, 25, 29 and 30. |
