Patent ID: 7238933

Claim:
A light detecting apparatus comprising: a two-axis deflector configured to deflect an incident light beam in a direction defined by two axes; a two-dimensional position detector configured to two-dimensionally detect an incident position on the detector of the deflected light beam from the two-axis deflector; a search controller configured to generate a search control signal that controls the two-axis deflector; and wherein the search controller conducting a search operation for finding an incident direction of a light beam made incident to the two-axis deflector by generating, as the search control signal, two periodic signals having different frequencies, by providing the two-axis deflector with the generated periodic signals, by independently controlling, with the periodic signals, deflective operations of the two-axis deflector along the two axes so that a deflected light beam from the two-axis deflector is made incident to the two-dimensional position detector, and by detecting an incident position of the deflected light beam on the two-dimensional position detector.