Patent ID: 8861322
Filing Date: 2014-10-14
Classification: G11B

Abstract:
1. An optical pickup comprising: a light source with first and second emission points; an optical branching element which branches light that has been emitted from the first emission point into multiple light beams including a first main beam and a first set of sub-beams and which also branches light that has been emitted from the second emission point into multiple light beams including a second main beam and a second set of sub-beams; an optical system which condenses the multiple light beams that have been produced by the optical branching element onto an optical storage medium, thereby making the first and second main beams form a write light beam spot and a read light beam spot, respectively, on a target recording track on the optical storage medium and making the first and second sets of sub-beams form reference light beam spots and other light beam spots somewhere on the optical storage medium other than the target recording track; and a photodetector, wherein the photodetector includes a plurality of photosensitive sections forming a first group which receive reflected light beams that have left the write light beam spot and the reference light beam spots, and a photosensitive section forming a second group which receives reflected light that has left the read light beam spot, wherein the photosensitive sections forming the first and second groups are arranged so as not to receive reflected light beams of the second set of sub-beams that have left the other light beam spots, and wherein the photosensitive section forming the second group is arranged between the photosensitive sections forming the first group.