# US 2008/0186838 A1 · Read-only optical disc medium and method of fabricating the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0186838 A1 - Document ID: US20080186838A1 - Status: Published application - Kind: A1 - Application number: 12/023,655 - Filed: 2008-01-31 - Published: 2008-08-07 - Earliest claimed: 2007-02-01 - Assignees: Sony Disc & Digital Solutions Inc. - Inventors: Takayuki Asahina - Web page: https://patentgrep.com/patent/US20080186838A1 ## CPC - G11B 7/00736: {Auxiliary data, e.g. lead-in, lead-out, Power Calibration Area [PCA], Burst Cutting Area [BCA], control information (sector headers or adresses in prepits G11B7/00745; address data in track wobble G11B7/24082)} - G11B 7/00451: {involving ablation of the recording layer} - G11B 7/0079: {Zoned data area, e.g. having different data structures or formats for the user data within data layer, Zone Constant Linear Velocity [ZCLV], Zone Constant Angular Velocity [ZCAV], carriers with RAM and ROM areas} - G11B 7/1267: Power calibration - G11B 19/122: {involving the detection of an identification or authentication mark (record carriers indicating unauthorised or prior use G11B23/28)} - G11B 7/00456: {Recording strategies, e.g. pulse sequences (G11B7/0062 takes precedence)} - G11B 7/268: {Post-production operations, e.g. initialising phase-change recording layers, checking for defects (investigating the presence of flaws or contamination in optical discs G01N21/9506)} - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract A read-only optical disc medium is disclosed. The disc medium includes: an information recording area in which information is recorded by means of an embossed pit array formed in a convexo-concave shape having a reflective layer deposited thereon; a test writing area which is used for test write recording of a mark formed by dissipating or decreasing the reflective layer; and an additional write area in which a record data string is formed of a mark by dissipating or decreasing the reflective layer under a recording condition decided in accordance with a result of test write recording performed in the test writing area. ## Claims ### Claim 1 A read-only optical disc medium comprising: an information recording area in which information is recorded by means of an embossed pit array formed in a convexo-concave shape having a reflective layer deposited thereon; a test writing area which is used for test write recording of a mark formed by dissipating or decreasing the reflective layer; and an additional write area in which a record data string is formed of a mark by dissipating or decreasing the reflective layer under a recording condition decided in accordance with a result of test write recording performed in the test writing area. ### Claim 2 (depends on 1) The read-only optical disc medium according to claim 1, wherein in the information recording area, a lead-in area, a main data area and a lead-out area are formed from an inner track side to an outer track side. ### Claim 3 (depends on 2) The read-only optical disc medium according to claim 2, wherein in the main data area, content data and dummy data are recorded. ### Claim 4 (depends on 2) The read-only optical disc medium according to claim 2, wherein the test writing area is provided on the outer track side than the lead-out area is provided. ### Claim 5 (depends on 2) The read-only optical disc medium according to claim 2, wherein the test writing area is provided on the inner track side than the lead-in area is provided. ### Claim 6 (depends on 2) The read-only optical disc medium according to claim 2, wherein the additional write area is provided near a position of a terminal end of the main data area. ### Claim 7 (depends on 2) The read-only optical disc medium according to claim 2, wherein the additional write area is provided near a position of a beginning end of the main data area. ### Claim 8 (depends on 2) The read-only optical disc medium according to claim 2, wherein the additional write area is provided on the inner track side of the lead-out area, and the test writing area is provided on the outer track side thereof, as the lead-out area is sandwiched. ### Claim 9 (depends on 2) The read-only optical disc medium according to claim 2, wherein the additional write area is provided on the outer track side of the lead-in area, and the test writing area is provided on the inner track side thereof, as the lead-in area is sandwiched. ### Claim 10 A method of fabricating a read-only optical disc medium comprising the steps of: forming an optical disc master having a convexo-concave shape thereon based on an information signal and having a flat area to be a test writing area and an additional write area; shaping a disc substrate having the convexo-concave shape and the flat area on an information recording surface thereof by using a stamper prepared from the optical disc master; depositing a reflective layer on the information recording surface to form an embossed pit array in the convexo-concave shape having the reflective layer deposited thereon and the test writing area and the additional write area as the flat area having the reflective layer deposited thereon; and performing test write of a mark formed by dissipating or decreasing the reflective layer in the test writing area, forming a mark by dissipating or decreasing the reflective layer in the additional write area under a recording condition decided in accordance with a result of the test write recording, and forming a record data string formed of the mark.