Apparatus and method for optical disk reproduction

摘要

An apparatus of the present invention is an optical disk apparatus for irradiating with a laser beam an optical disk on which address marks (100) are recorded at intervals based on a pulse width modulation method and for reproducing data from a reproduced signal based on reflected light. The apparatus includes: a pulse signal reproduction section for producing a reproduced pulse signal (ADR) from the reproduced signal based on a threshold value (VTH); a threshold value production section for producing the threshold value based on the reproduced pulse signal; and a gate signal production section for producing an address gate signal (ADRG) at a timing when the address mark is reproduced. <IMAGE>