| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup device capable of providing a stable verification function considering the scan line velocity of an optical recording medium. <P>SOLUTION: The optical pickup device includes: a laser light source 1 that emits a light beam; diffraction element 2 that diffracts the light beam and branches into plural diffraction lights including a 0-th diffraction light and ±1-th diffraction light; an objective lens 7 that collects the 0-th diffraction light and the ±1-th diffraction light on an identical track on the optical recording medium; and a photodetector 8 that receives the 0-th diffraction light and the ±1-th diffraction light reflected from the optical recording medium. Defining a distance between an optical spot formed on the track of the optical recording medium by the 0-th diffraction light and an optical spot formed on the track by the ±1-th diffraction light as d[μm]; the a scan line velocity of the optical recording medium as v[m/s]; and the time required for a phase change material of the optical recording medium to get solidified from being melted by the 0-th diffraction light as T[μs], vT≤d is satisfied. <P>COPYRIGHT: (C)2013,JPO&INPIT |
