Patent ID: 8184954

Claim:
An information recording medium for being able to record data by additional writing or re-writing, said information recording medium comprising: a groove track wholly wobbling at 140 kHz at the normal scanning velocity which is defined by the DVD-R standard or the DVD-RW standard in order that 140 kHz at the normal scanning velocity is not detected by a reproduce apparatus, which uses a wobble detection method based on a self-correlation and comprising (i) a delay step of delaying a wobble signal for a half-period corresponding to 140 kHz at the normal scanning velocity; and (ii) an exclusive OR step of XORing the wobble signal and the delayed wobble signal; and key information, which is pre-recorded in a control data zone which is included in the groove track, for encrypting the record data on the basis of the CSS (Content Scrambling System) encryption method, wherein one sync frame is formed by the “8 times N” pieces of pre-formatted wobbles included in the groove track (wherein “N” is an even number; “N” is equal to a ratio of (i) the frequency at which the groove track wobbles to (ii) 140 kHz, in the sync frame, the pre-formatted wobbles are grouped into group units by N pieces from a head position of the sync frame, one Land Pre-Pit is formed in each of one, two or three group units from the head position of the sync frame.