# US 6,295,257 B1 · Information recording medium, information recording method, information recording apparatus and information reproducing apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,295,257 B1 - Document ID: US6295257B1 - Status: Granted - Kind: B1 - Application number: 09/591,832 - Filed: 2000-06-12 - Granted: 2001-09-25 - Earliest claimed: 1999-03-08 - Assignees: Matsushita Electric Industrial Co., Ltd. - Inventors: Motoshi Ito; Hiroshi Ueda; Yoshiho Gotoh; Yoshihisa Fukushima - Web page: https://patentgrep.com/patent/US6295257B1 ## CPC - G11B 20/1883: {Methods for assignment of alternate areas for defective areas} - G11B 20/1833: {by adding special lists or symbols to the coded information (G11B20/1806, G11B20/1866 take precedence)} - H03M 13/35: Unequal or adaptive error protection, e.g. by providing a different level of protection according to significance of source information or by adapting the coding according to the change of transmission channel characteristics - G11B 2020/10944: {Real-time recording or reproducing, e.g. for ensuring seamless playback of AV data} - G11B 2020/1823: {wherein a flag is set when errors are detected or qualified} - G11B 2020/1826: {wherein a defect list or error map is generated} - G11B 2020/1893: {using linear replacement to relocate data from a defective block to a non-contiguous spare area, e.g. with a secondary defect list [SDL]} - G11B 2020/1896: {using skip or slip replacement to relocate data from a defective block to the next usable block, e.g. with a primary defect list [PDL]} - G11B 2220/20: Disc-shaped record carriers - 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) - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) ## Abstract An information recording medium of the present invention includes: a volume space in which user data is recorded; a spare area including a replacement area which may be used in place of a defective area included in the volume space; and a defect management information area in which defect management information for managing the defective area is recorded. The defect management information includes status information indicating whether the defective area is replaced by the replacement area. ## Claims ### Claim 1 An apparatus for reproducing information recorded on an information recording medium including a volume space for recording user data; a spare area including a replacement area which is usable in place of a defective area included in the volume space; and a defect management information area for recording defect management information for managing the defective area, the defect management information including status information indicating whether the defective area is replaced by the replacement area, the apparatus comprising: a determination section for determining whether the defective area is replaced by the replacement area with reference to the status information; and a control section for controlling a reproduction operation of the user data according to the determination result, wherein when the defective area is not replaced by the replacement area, the control section outputs data having a fixed value as data obtained by reproducing the defective area, regardless of data in the defective area. ### Claim 2 (depends on 1) An apparatus according to claim 1, wherein: the defect management information includes a primary defective list and a secondary defective list, the secondary defective list includes first location information indicating a location of the defective area, second location information indicating a location of the replacement area, and a flag indicating whether the defective area is replaced by the replacement area. ### Claim 3 (depends on 1) An apparatus according to claim 1, wherein: the defective area is detected as a unit of a ECC block which is a unit of an error correction operation; the defective area is replaced by the replacement area as a unit of the ECC block, the error correction operation includes a first error correction operation for correcting errors within a single sector and a second error correction operation for correction errors over a plurality of sectors, and when the defective area is not replaced by the replacement area, the control section performs the first error correction operation for the data in the defective area so as to output data which is corrected by the first error correction operation. ### Claim 4 (depends on 2) An apparatus according to claim 2, wherein: the defective area is detected as a unit of a ECC block which is a unit of an error correction operation, the defective area is replaced by the replacement area as a unit of the ECC block, the error correction operation includes a first error correction operation for correcting errors within a single sector and a second error correction operation for correcting errors over a plurality of sectors, and when the defective area is not replaced by the replacement area, the control section performs the first error correction operation for data in the defective area so as to output data which is corrected by the first error correction operation.