| 摘要 |
An optical pickup device has an astigmatism element which imparts astigmatism to reflected light of laser light reflected on a recording layer, and a spectral element into which the reflected light is entered, and which separates the reflected light. The spectral element is divided into six second areas by a straight line in parallel to a first direction, a straight line in parallel to a second direction, and a first area having a predetermined width and formed along a straight line in parallel to a third direction inclined from the first direction by 45 degrees. The spectral element is configured to guide the reflected light passing through the six second areas to corresponding sensors on a photodetector while making propagating directions of the reflected light different from each other, and to avoid guiding the reflected light entered into the first area to the sensors. |
