Information recording medium and playback device

Abstract

An optical disk (100) of the present invention includes (i) a medium information region (101) (a) in which type identification information is recorded by recesses and/or protrusions which are formed by a given modulation method and whose lengths are longer than a length of an optical system resolution limit of a playback device and (b) in which first address information is recorded in a first address data format and (ii) a data region (102) (a) in which content data is recorded by recesses and/or protrusions which are formed by the given modulation method and which include a recess and/or a protrusion whose length is shorter than the length of the optical system resolution limit and (b) in which second address information is recorded in a second address data format.

1 . An information recording medium comprising:
 a first region in which type identification information for identifying a type of the information recording medium is recorded by recesses and/or protrusions which are formed by a given modulation method and whose lengths are longer than a length of an optical system resolution limit of a playback device; and   a second region in which content data is recorded by recesses and/or protrusions which are formed by the given modulation method and which include a recess and/or a protrusion whose length is shorter than the length of the optical system resolution limit,   the first region containing first address information recorded therein in a first address data format,   the second region containing second address information recorded therein in a second address data format that differs from the first address data format,   the information recording medium further comprising a blank region between the first region and the second region, the blank region (i) including a portion in which the first address data format is switched to the second address data format and (ii) including address information and no significant information other than the address information,   the second region having a track pitch shorter than a track pitch of the first region,   the blank region having a track pitch which is, at a boundary between the blank region and the second region, equal to a trach pitch of the second region, and   the given modulation method being a 1-7PP (Parity Preserve/Prohibit RMTR (Repeated Minimum Translation Run Length)) modulation recording method.   
     
     
         2 . A playback device for playing back an information recording medium recited in  claim 1 ,
 said playback device comprising:   a first address information decoding process section for decoding the first address information recorded in the first region; and   a second address information decoding process section for decoding the second address information recorded in the second region,   said playback device playing back a region on an outer side of the blank region with the second address information decoding process section.