| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup device for accurately performing a gap control and a focus control with a relatively simple configuration when recording and reproducing information onto a recording medium having a plurality of recording layers using a near-field optical system. <P>SOLUTION: An optical pickup device including a near-field optical system, a first and second light sources, an optical system, a first and second photodetectors, a controller, and a mechanism for adjusting a focus position, is provided. The near-field optical system performs recording and reproducing, using the first and second light sources emitting light of a first and a second wavelengths, respectively. Here, a reproduction signal, a tracking signal and a focus signal corresponding to each recording layer is obtained by means of return light of the first wavelength from the optical recording medium, and a signal for a gap control is obtained by means of return light of the second wavelength. <P>COPYRIGHT: (C)2010,JPO&INPIT |
