Patent ID: 7911908
Filing Date: 2011-03-22
Classification: G11B

Abstract:
1. An optical data processing apparatus for reading and/or writing data from/on first and second data storage media of different types, comprising: a light source for radiating light; a focusing optical system for forming a focal spot by condensing the light that has been emitted from the light source; a light detector, which includes at least one photodetector for receiving the light and generating a light quantity signal representing a quantity of the light received; a detecting optical system for guiding reflected light beams, which have been reflected from a storage layer of a loaded storage medium to the light detector; and a signal processor for generating a layer sensing signal from the light quantity signal and recognizing the type of the loaded data storage medium by the layer sensing signal, wherein the light detector includes, as the at least one photodetector, a layer sensing photodetector, which is arranged in view of an area of the light detector where: wherein the light detector further includes a photodetector which receives the reflected light beam to generate a focus error signal and which is different from the layer sensing photodetector.