| 摘要 |
<p>To achieve a tracking error detection device with a simple optical system that is associated with a reduced offset resulting from the lateral movement of an objective lens or a tilt of an information recording medium and that can maintain the maximum amplitude of a tracking error signal irrespective of variations in track pitch of the information recording medium, a light beam having substantially-half portions about 180 degrees out of phase with each other, and another light beam are directed and focused via the objective lens to an information recording medium, the light spots formed by the two light beams are disposed on the information recording medium with a spacing of substantially an integral multiple of the track pitch in the direction perpendicular to the tracks on the information recording medium, each light beam returning from the information recording medium is received by a pair of split photodetectors, and a tracking error signal is obtained from the difference between the differential outputs. <IMAGE></p> |
