| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a compatible-type optical pickup device which effectively suppresses stray light with simple constitution. <P>SOLUTION: BD light or CD light reflected by a BD or CD is subjected to introduction of astigmatism by a detection lens 109. Thereafter, in the BD light or CD light, luminous fluxes in four luminous flux areas established around a laser light axis are separated from each other by diffraction operation by means of a spectral device 110. On the detection surface of a photodetector, sensors P21 to P28 for photodetecting the BD light and sensors P31 to P38 for photodetecting the CD light are arranged. The DVD light is separated to be 3 beams by a diffraction grating 102 and applied onto a DVD. DVD light reflected by the DVD is not separated by the spectral device 110 and photodetected by sensors P41 to P43. According to a space S1 between sensor patterns, a gap G2 between laser elements within a semiconductor laser 101 is established. <P>COPYRIGHT: (C)2011,JPO&INPIT |
