Mark forming apparatus, method of forming laser mark on optical disk, reproducing apparatus, optical disk and method of producing optical disk

A method of forming a laser marking to an optical disk, comprising the steps of:

• forming at least one disk;
• forming a reflective film to said formed disk;
• laminating two disks together, said disks including at least one disk with said reflective film formed thereon;
• and
• forming at least one marking by a laser on said reflective layer of the laminated disks.

A reproduction apparatus comprising:

• position information reading means for reading position information of at least one marking or information concerning said position information, said marking being formed to at least one reflective film formed to a disk and being detected for a position thereof, at least the position thus detected being output as said position information of said marking;
• marking reading means for reading information concerning at least one actual position of said marking;
• comparing/judging means for performing comparison and judgement by using a result of reading by said position information reading means and a result of reading by said marking reading means;
• and
• reproducing means for reproducing recorded data on said optical disk in accordance with a result of the comparison and judgement performed by said comparing/judging means.

A method of manufacturing an optical disk, comprising the steps of:

• forming at least one disk;
• forming a reflective film to said formed disk;
• applying at least one marking to said reflective film;
• detecting at least one position of said marking;
• and
• outputting said detected position as position information of said marking, and encrypting said information for writing to said disk.

A method of manufacturing an optical disk, comprising the steps of:

• forming at least one disk;
• forming a reflective film to said formed disk;
• applying at least one marking to said reflective film;
• detecting at least one position of said marking;
• and
• outputting said detected position as position information of said marking, and applying a digital signature in relation to said position information for writing to said disk.

An optical disk comprising:

• a data zone having pits indicating data signals readable by light radiation;
• a reflective layer formed on the data zone;
• and
• portions of the reflective layer being trimmed by a laser forming markings,
• wherein the markings form a barcode pattern indicating information and are formed on a track of the optical disk, and the pits are provided between successive markings of the barcode pattern.

A method of manufacturing an optical disk comprising the steps of:

• forming, on a substrate, a data zone having pits indicating data signals readable by light radiation;
• forming a reflective layer on the data zone;
• and
• trimming the reflective layer to form markings on a track of the optical disk;
• wherein the markings form a barcode pattern indicating information and the pits are provided between successive markings of the barcode pattern.