{TAIL ~ A signal} having a predetermined pattern is written in a predetermined region of an optical disc at a plurality of {HEAD ~ different write power levels} Pwm 
{ TAIL ~ A signal } having a predetermined pattern is written in a predetermined region of an optical disc at a plurality of { HEAD ~ different write power levels } Pwm
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH