| 摘要 |
PURPOSE:To enable the reproduction of the signal of the recording medium recorded with high density by having a slit that longitudinal direction of the aperture in the shading of the slit member becomes parallel to the moving direction of the information recording part when the projection is performed on the information recording part. CONSTITUTION:The slit member 18 is arranged so that the elongation direction of a slit 19 may be parallel to the track direction of a bit string 20, when the image of the slit 19 is formed on an optical disk 11 via the detection optical system. When the center strength of the light entering the objective lens pupil is interrupted circularly, the modulation degree of the reproduced signal in the high band of spatial frequency when the slit direction is parallel to the track direction becomes higher than when the slit direction is perpendicular to the track direction or when the slit shape is pinhole. Therefore, it is effective for the reproduction of the optical disk recorded with high density and the crosstalk component can be removed. |
