Patent ID: 6507544
Filing Date: 2003-01-14
Classification: G11B

Abstract:
An error signal detection apparatus for an optical recording/reproducing system, comprising;a photodetector which detects an information signal by receiving light reflected and diffracted from a recording medium, the photodetector comprising eight light receiving portions arranged in a 2 rowÃ—4 column matrix, each light receiving portion to separately perform photoelectric conversion on light reflected and diffracted from the recording medium to generate a respective detection signal, the row of the matrix being parallel to a direction corresponding to a radial direction of the recording medium, the column of the matrix being parallel to a direction corresponding to a tangential direction of the recording medium, the eight light receiving portions including four inner light receiving portions arranged at a center region of the photodetector and four outer light receiving portions arranged around corresponding inner light receiving portions, a direction of an information stream recorded on the recording medium being defined as the tangential direction, and a direction perpendicular to the information stream being defined as the radial direction; and a circuit unit which compares the phases of the detection signals of the inner and/or outer light receiving portions arranged in the same row to output at least one of a tilt error signal and/or a tracking error signal based on the phase comparison.