DEVICE AND METHOD FOR INFORMATION RECORDING AND REPRODUCING AND OPTICAL PICKUP

摘要

PROBLEM TO BE SOLVED: To reduce the size of an optical pickup by changing the location of a front photodetector. SOLUTION: Laser light beams emitted from a laser diode 11 are converted into parallel light beams by a collimator lens 12 and made incident on an anamorphic prism 13. The prism 13 reflects a portion of the incident laser beams being incident on the surface 13A to the direction of a front photodetector 14. The photodetector 14 transforms the laser beams being incident into electric signals and outputs the signals to a succeeding stage computing circuit.