Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
176 words
In an information recording and reproduction apparatus comprising an optical disc (1) including a plurality of sectors, each of said sectors having a sector identification section ID having an address data recorded therein and a data field section DF for recording data, and means (2) for recording and reproducing data in said sector of the optical disc, the improvement further comprising means (3, 5, 8) for detecting a defective sector having a defect in said sector identification section ID and/or said data field section DF, means (2) for recording a first signal (107) different from the data in the data field section DF of said sector, means - ( 1 0) for overwriting a second signal (108) in the sector identification section ID that causes a read error of the address information, and means (11) for detecting the first signal recorded in the data field DF of said sector, said first signal being recorded in the data field section DF of a defective sector, said second signal being recorded overlapped in the sector identification section thereof.
Claim 2
Dependent Claim
176 words
In an information recording and reproduction apparatus comprising an optical disc (1) including a plurality of sectors, each of said sectors having a sector identification section ID having an address data recorded therein and a data field section DF for recording data, and means (2) for recording and reproducing data in said sector of the optical disc, the improvement further comprising means (3, 5, 8) for detecting a defective sector having a defect in said sector identification section ID and/or said data field section DF, means (2) for recording a first signal (107) different from the data in the data field section DF of said sector, means - ( 1 0) for overwriting a second signal (108) in the sector identification section ID that causes a read error of the address information, and means (11) for detecting the first signal recorded in the data field DF of said sector, said first signal being recorded in the data field section DF of a defective sector, said second signal being recorded overlapped in the sector identification section thereof.
Claim 3
Dependent Claim
66 words
An apparatus according to Claim 1, further comprising means (3, 4, 6, 7) for replacing a defective sector with another sector, wherein upon detection of a first signal, said defective sector replacing means is activated by being informed that data should be recorded in a replacement sector regarding a target sector as defective, and that the target sector is already replaced at the time of reading.
Claim 4
Dependent Claim
40 words
An apparatus according to Claim 1, wherein a first signal is recorded in the data field section DF of a defective sector and then a second signal is written overlapped in the sector identification section ID of the same sector.
Claim 5
Independent Claim
20 words
An apparatus according to any of Claims 1 to 3, wherein said first signal contains a replacement sector data therein.
Claim 6
Independent Claim
33 words
An apparatus according to any of Claims 1 to 4, wherein said first signal contains a signal component lower in frequency than the data modulation signal recorded in the data field section DF.
Claim 7
Dependent Claim
21 words
An apparatus according to Claim 1, wherein said second signal indicates that said first signal is recorded in the data field.
Claim 8
Dependent Claim
46 words
An apparatus according to Claim 1, wherein a given sector is determined as defective when a read error occurs of the sector identification section ID of said sector, said sector being determined defective also when a dropout is detected in the data field section DF thereof.
Claim 9
Dependent Claim
55 words
An apparatus according to Claim 1 , wherein data having an error correction code is recorded in and read from the data field section DF, an error flag is produced from the error syndrome of a demodulated data, and a sector with the error flag exceeding a predetermined reference is determined as a defective sector.