Background Art Optical disks, which are optical information storage media, are widely used in optical pickup devices that record/reproduce information in a non-contact manner. Types of optical disks are compact discs (CD) and digital versatile discs (DVD), and high density DVDs (HD-DVD).

Optical disks capable of recording, erasing, and reproducing data are CD-R, CD-RW, DVD-RW, DVD-RAM, DVD+RW, or the like.

In DVD+RW disks, a basic recordable unit capable of recording a predetermined amount of data is called an ECC block. A method of recording data to several ECC blocks is shown in FIG. 1A. In the prior art, when data is recorded sequentially, linking can be properly performed by using the last 8-channel bit 100-a of an ECC block before an N-th ECC block 102, where recording starts. Since linking may not start at an exact location due to an error in the number of rotations of a disk during recording, a spare area of 5T is provided so that recording can start in a spare area. In other words, by providing the spare area of 5T between an ideal recording start point and a real recording start point, if recording starts anywhere within the spare area, proper recording can be performed.

To follow the above-described linking system, the last 8-channel bit 104-a of the ECC block 104 remains unrecorded so that linking for consecutive recording is properly accomplished.

A conventional consecutive recording method based on the linking system is shown in FIG. 1 B. Referring to FIG. 1 B, data is recorded in an (N-1) th ECC block 100 excluding the last 8-channel bit 100-a. After the recording of the (N-1) th ECC block 100, while M ECC blocks starting from the N-th ECC block 102 are being recorded, linking occurs in the last 8 channel bit 100-a of the (N-1) th ECC block 100.

Only the last 8 channel bit 104-a among the bits of the (N+M-1) th ECC block 100 is unrecorded.

FIG. 1 C shows a case where data is recorded in a blank area to which data was not recorded. If an (N-2) th ECC block 110 right before a (N-1) th ECC block 112 where recording starts is a blank block to which data was not recorded, dummy data is recorded in the (N-1) th ECC block 112, and recording of user data starts from an N-th ECC block 114.

Here, recording of the dummy data starts from the last 8 channel bit 110-a of the (N-2) th ECC block 110. The last 8-channel bit 116-a of a (N+M-1) th ECC block 116 where recording ends remains unrecorded.

In the prior art, it has been prescribed how linking occurs in a case where consecutive recording is performed on a DVD+RW, while it has not been prescribed how linking system is applied if a defective block is generated between ECC blocks where consecutive recording is being performed. Also, a method of consecutive recording and a method of recording data in a blank disk block are specified in the prior art, while data overwriting to a disk where data has already been recorded has not been prescribed. Thus, there is a need to prescribe how linking occurs if a defective block is generated and how overwriting is performed.

Disclosure of the Invention

The present invention provides a method of recording data in the case of overwriting of data to a DVD+RW, a method of recording data in the case of recording of data to an area including a defective area, and an optical disk to which data is recorded according to the recording method.

According to an aspect of the present invention, there is provided a method of recording an optical disk in the case of overwriting data to a recordable/reproducible optical disk, the method comprising performing linking by overlappingly recording data to the end portion of the ECC block right before an ECC block where the overwriting starts.

According to another aspect of the present invention, there is provided a method of recording an optical disk in the case of data recording to an area including a defective ECC block in a recordable/reproducible optical disk, the method comprising ending the data recording right before the defective ECC block.

Preferably, data recording starts at the last 8 channel bits of the ECC block immediately after the defective ECC block.

It is also preferable that data recording starts at the ECC block immediately after the defective ECC block.

According to another aspect of the present invention, there is also provided a method of recording data in the case of data recording to an area including a defective ECC block in a recordable/reproducible optical disk, the method comprising ending the data recording right before the last 8 channel bits of the ECC block right before the defective ECC block.

According to still another aspect of the present invention, there is provided a recordable/reproducible optical disk, in which in the case of overwriting of data to part of the optical disk where data has been recorded, linking is performed by overlappingly recording data to the end portion of the ECC block immediately before an ECC block where the overwriting starts.

According to still another aspect of the present invention, there is also provided a recordable/reproducible optical disk, in which in the case of data recording to an area including a defective ECC block, the data recording ends right before the defective ECC block and resumes from the last 8 channel bits of the ECC block immediately after the defective ECC block.

According to still another aspect of the present invention, there is also provided a recordable/reproducible optical disk, in which in the case of data recording to an area including a defective ECC block, the data recording ends right before the defective ECC block and resumes from an ECC block immediately after the defective ECC block.

Brief Description of the Drawings FIG. 1A illustrates a recording method performed in a conventional DVD+RW; FIG. 1 B illustrates the occurrence of linking upon consecutive recording in a conventional DVD+RW; FIG. 1C illustrates the occurrence of linking when data is recorded in a blank area of a conventional DVD+RW; FIG. 2 illustrates an overwriting method based on a method of recording data to an optical disk, according to a first embodiment of the present invention; FIGS. 3A and 3B illustrate a method of recording data to an optical disk, according to a second embodiment of the present invention; FIGS. 4A and 4B illustrate a method of recording data to an optical disk, according to a third embodiment of the present invention; FIGS. 5A and 5B illustrate a case in which a method of recording data to an optical disk, according to a fourth embodiment of the present invention, is performed; and FIGS. 6A and 6B illustrate another case in which the data recording method according to the fourth embodiment of the present

invention is performed.

Best mode for carrying out the Invention Referring to FIG. 2, in an optical disk and a recording method for the optical disk according to a first embodiment of the present invention, when data is overwritten from an N-th ECC block 12 among pre-written blocks, data recording starts from the end portion of an (N-1) th ECC block 10 before the N-th ECC block 12. The end portion is an area where data has already been recorded, where linking occurs while data are being overlapped to be recorded. Preferably, data recording starts from the last 8 channel bits 10-a of the ECC block right before an ECC block where data recording is to start. In other words, if a disk has already been written, and some area of the disk, for example, M ECC blocks starting from the N-th ECC block 12, is to be overwritten, linking occurs in the last 8 channel bits 10-a of the (N-1) th ECC block 10 before the N-th ECC block 12.

Here, the last 8 channel bits 14-a of an (N+M-1) th ECC block 14 where overwriting ends are not overwritten.

In an optical disk and a method of recording data in the optical disk, according to a second embodiment of the present invention, as shown in FIG. 3A, if recording is performed in an area including a - defective ECC block 26, the recording ends before the last 8 channel bits 24-a of an ECC block 24 before the defective ECC block 26. In other words, when data are to be recorded in (M+2) blocks starting from an (N-2) th ECC block 22, if the defective N-th ECC block 26 is included, linking occurs in the last 8 channel bits 20-a of an (N-3) th ECC block 20 before the (N-2) th ECC block 22.

Thereafter, data recording ends before the last 8 channel bits 24-a of the (N-1) th ECC block 24 before the N-th defective ECC block 26 and resumes from the last 8 channel bits 28-a of an (N+1) th ECC block 28 next to the N-th defective ECC block 26.

In the example of FIG. 3A, recording resumes from the last 8 channel bits 28-a of the (N+1) th ECC block 28 next to the defective ECC block 26. However, as shown in FIG. 3B, recording may resume from the beginning of the (N+1) th ECC block 28 next to the defective ECC block 26. Thus, data area of 32KB can be further secured.

In an optical disk and a method of recording data in the optical disk, according to a third embodiment of the present invention, as shown in FIG. 4A, when (M+2) ECC blocks starting from the (N-2) th ECC block 22 are to be written, if they include the N-th defective ECC block 26, recording starts from the last 8 channel bits 20-a of the (N-3) th ECC block 20 before the (N-2) th ECC block 22. The recording ends before the N-th defective ECC block 26, since linking does not need to occur before a defective block, and accordingly, no spare area for linking is needed.

Thereafter, recording resumes from the last 8 channel bits 28-a of the (N+1) th ECC block 28 next to the N-th defective ECC block 26 and continues until the (N+M-1) th ECC block 32. At this time, the last 8 channel bits 32-a of the (N+M-1) th ECC block 32 remain unwritten.

However, as shown in FIG. 4B, recording may resume from the beginning of the (N+1) th ECC block 28 next to the defective N-th ECC block 26. Accordingly, a data area of 32KB can be further secured as compared to the recording method of FIG. 4A. After recording starts from the (N+1) th ECC block 28, the recording ends at the (N+M-1) th ECC block 32 while its last 8 channel bits 32-a remain unwritten.

The second and third embodiments can be applied to cases where recording is performed on a blank area of a DVD+RW, where consecutive data recording is performed, and where part of an area to which data has already been recorded is overwritten. Here, a defect may be generated before the start of recording or during recording.

Also, the second and third embodiments according to the present invention are applicable to disks with a capacity of 4.7GB.

An optical disk and a recording method for the optical disk according to a fourth embodiment of the present invention provides how a linking system works when the block before an area in which data is to be recorded is defective.

FIG. 5A shows an area of an optical disk on which a data recording according to the present invention is not yet performed, and FIG. 5B shows an area of an optical disk on which a data recording according to the present invention has been performed. Referring to FIG. 5A, as described above, some area of a user area, for example, an (N-2) th ECC block 36, an (N-1) th ECC block 37, and an N-th ECC block 38, has already been written, and linking occurs in the last 8 channel bits 35-a of an (N-3) th ECC block 35. Blocks from an (N+1) th ECC block 39 to an (N+M-1) th ECC block 42 remain unwritten, that is, blank. When recording is performed on (M-1) ECC blocks from the (N+1) th ECC block 39 to the (N+M-1) th ECC block 42, if the N-th ECC block 38 before the (N+1) th ECC block 39 where recording is to start is defective, the last 8 channel bits 38-a of the defective N-th ECC block 38 cannot be used for linking. Accordingly, an extra area for linking is required.

The extra area for linking is shown in FIG. 5B. User data cannot be recorded in the (N+1) th ECC block 39 next to the defective N-th ECC block 38, but data for linking is recorded in the last 8 channel bits 39-a of the (N+1) th ECC block 39. If the (N+1) th ECC block 39 before the (N+2) th ECC block 40 where recording starts is unwritten, that is, blank, dummy data is recorded in an (N+2) th ECC block 40 according to the above-described specification, and user data recording starts from an (N+3) th ECC block 41. The user data recording ends at the (N+M-1) th ECC block 42 while its last 8 channel bits 42-a remain unwritten so as to be used for linking.

While FIG. 5A shows a case in which an area where data is to be recorded is unwritten, that is, blank, FIG. 6A shows a case in which an area where data is to be recorded has already been written. To be

more specific, FIG. 6A shows an area of an optical disk in which a data recording according to the present invention is not yet performed, and FIG. 6B shows an area of an optical disk in which a data recording according to the present invention has already been performed.

As described above, (N-2) th, (N-1) th, and N-th ECC blocks 46,47, and 48 have already been written, and linking occurs in the last 8 channel bits 45-a of an (N-3) th ECC block 45. When overwriting is performed on (M-1) ECC blocks from (N+1) th through (N+M-1) th ECC blocks 49 through 51 in which data has already been recorded, if an N-th ECC block 48 before the (N+1) th ECC block 49 where recording is to start is defective, the last 8 channel bits 48-a of the defective N-th ECC block 48 cannot be used for linking because of the defect.

Accordingly, data for linking is recorded on the (N+1) th ECC block 49 next to the defective N-th ECC block 48, more preferably, on the last 8 channel bits 49-a of the (N+1) th ECC block 49. Consequently, as shown in FIG. 6B, data recording starts from the last 8 channel bits 49-a of the (N+1) th ECC block 49 and ends at an (N+M-1) th ECC block 51 while its last 8 channel bits 51-a remain unwritten so as to be used for linking.

As described above, the method of recording data in the optical disk according to the fourth embodiment of the present invention proposes a data linking approach if the block before a block to be written is defective. The recording method according to the fourth embodiment is applicable to both a case where a block to be written is blank, that is, unwritten, and a case where the block to be written has already been written. industrial Applicability To sum up, an optical disk and a method of recording data to an optical disk according to the present invention propose a method of processing a defective block to accomplish the compatibility of a

DVD+RW disk with a disk drive. To be more specific, the present invention provides an overwriting method not prescribed in the prior art, a method of recording data in a predetermined area including a defective area, and a method of performing linking when the block before a block to be written is defective. Thus, an optical disk is consistently recorded/reproduced.