| 摘要 |
<P>PROBLEM TO BE SOLVED: To carry out focus control and tracking control by a DPP (Differential Push-Pull) method in either case an optical disk is a CD or DVD. <P>SOLUTION: In an optical pickup capable of recording or reproducing information on a 1st and a 2nd optical disks (CD, DVD) having different track pitches from each other as the optical disk, a dual wavelength laser (21) is provided with two light sources arranged for emitting a 1st and a 2nd laser beams (L1, L2) having different wavelengths from each other for the 1st and 2nd optical disks in the same direction. A diffraction means (22) is arranged so as to separate each of the 1st and 2nd laser beams emitted from the dual wavelength laser into three beams, and is constituted so that the DPP method can be adopted as focus control and tracking control when recording and reproduction is made on the 1st and 2nd optical disks. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
