Patent ID: 7307936
Filing Date: 2007-12-11
Classification: G11B

Abstract:
1. A disk drive device comprising: head means for performing laser output for the purpose of recording or playing back data to or from a disk-shaped recording medium on which grooves are formed as recording tracks and address information is recorded by prepits on lands between the grooves; push-pull signal generation means for generating a push-pull signal from reflected light information detected by said head means; window generation means for generating a window signal by binarizing said push-pull signal by using a first threshold level; integration means for integrating said push-pull signal only in a period in which the window signal is active; and extraction means for extracting address, information recorded by said prepits from the output of said integration means, wherein said extraction means comprises, a binarization circuit for binarizing an output of said integration means on a basis of a second threshold level, a mono-multivibrator for extending an output signal of the binarization circuit in a time direction, and a flip-flop for latching an output of the mono-multivibrator in accordance with a predetermined clock.