Matsushita Electric Industrial Co., Ltd.

Hideki Ohyama

Shogo Horinouchi

Takashi Inoue

Yasumori Hino

Eiji Ueda

Kiyokazu Hashimoto

Optoelectronic IC package

A tracking error signal detector includes: a photodetector ( ) for detecting reflected light from an optical recording medium having a servo area provided with a first wobble mark and a second wobble mark; an amplifier ( ) for producing a summation signal of the reflected light; a sampling portion ( ) for sampling the summation signal; a first arithmetic portion ( ) for calculating an extremum of the summation signal in the vicinity of reproduction timing for each of the first and second wobble marks from the sampling values so as to produce first and second extremums; and a second arithmetic portion ( ) for producing a tracking error signal that corresponds to a difference between the first and second extremum. The tracking error signal detector can produce a high-accuracy tracking error signal even if sampling is performed with an asynchronous clock relative to the summation signal.

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Fukuoka, Japan

Hideki Ohyama