Apparatus for reading from or writing to optical recording media

摘要

The present invention relates to an apparatus for reading from and/or writing to optical recording media, having a photodetector (10) and a phase detector (13) for detecting a phase difference (ϕ) between output signals (A+C, B+D) of the photodetector (10). An object of the present invention is to propose an apparatus in which a phase signal (ϕ) which is as correct as possible is generated. A further object of the invention is to specify a method by means of which a correct track error signal (TE) is determined using a phase detection method. According to the invention, to those ends the apparatus has an edge sequence detector (14) for detecting the sequence of edges of the output signals (A+C, B+D), and a signal blocking unit (15) for blocking the output signal (ϕ) of the phase detector (13). <IMAGE>