Patent ID: 6940799

Claim:
A method for generating a signal for detecting a direction of movement of a laser spot in an optical disc recording/reproducing apparatus having a photodetector divided into sections, each of which is a light receiving device aligned in a radial direction, the method comprising: detecting a phase difference between light receiving signals corresponding to light receiving devices of the photodetector, and obtaining a first phase difference signal that indicates the degree to which the phase of the light receiving signal corresponding to a first light receiving device in the radial direction leads the phase of the light receiving signal corresponding to a second light receiving device; and a second phase difference signal that indicates the degree to which the phase of the light receiving signal corresponding to the second light receiving device leads the phase of the light receiving signal corresponding to the first light receiving device; integrating the first and second phase difference signals; and adding the integrated first and second phase difference signals to each other to obtain a direction detecting signal.