1. Field of the Invention
The present invention relates to an optical recording medium and to a recording apparatus for forming the recording medium.
2. Description of the Related Art
On a recordable optical recording medium such as DVD-R and DVD-RW, when new information data is written behind a location that has already been written, a linking region is formed at that junction portion. Synchronization data for reading the information data written into a data region, which follows the linking region, is written into the linking region.
However, the fact that linking regions are formed on such a recordable recording medium leads to a problem that there is a possibility of incompatibility in the recording format with read-only recording media such as DVD-ROMs that are not recordable.
It is an object of the present invention to provide a read-only optical recording medium that is compatible with recordable optical recording media in the recording format and, apparatus and method for forming the read-only optical recording medium.
An optical recording medium having recorded data on a track thereof, according to the present invention, comprises on the track: a plurality of data block regions each of which includes main data of a block which serves as an error correction unit for the main data and which is divided into a predetermined number of main data pieces, each of which has data for identifying the main data; and linking regions each of which has pseudo data and is inserted between the plurality of data block regions; wherein when the linking regions on the track are adjacent, recording patterns of the pseudo data of the adjacent linking regions are different from each other.
A recording apparatus for recording data onto a track of an optical recording medium, according to the present invention, comprises: a main data recording device which forms on the track a plurality of data block regions each of which includes main data of a block which serves as an error correction unit for the main data and which is divided into a predetermined number of main data pieces, each of which has data for identifying the main data; and a linking data recording device which inserts linking regions each of which has pseudo data between the plurality of data block regions onto the track; wherein the linking data recording means, when the linking regions on the track are adjacent, forms the pseudo data of the adjacent linking regions with recording patterns which are different from each other.
A recording method for recording data onto a track of an optical recording medium, according to the present invention, comprises the steps of: forming on the track a plurality of data block regions each of which includes main data of a block which serves as an error correction unit for the main data and which is divided into a predetermined number of main data pieces, each of which has data for identifying the main data; and inserting linking regions each of which has pseudo data between the plurality of data block regions onto the track; wherein when the linking regions on the track are adjacent, the pseudo data of the adjacent linking regions is formed with recording patterns which are different from each other.
The present invention will be described below in more detail with reference to the accompanying drawings in accordance with the embodiments.
The master clock generator 11 generates a master clock signal, and supplies the master clock signal to the PLL circuit 12 and the servo controller 17. The servo controller 17 is supplied with the master clock signal, and with a frequency signal FG indicating a rotation frequency from the spindle motor 16. The servo controller 17 carries out rotation control for the spindle motor 16 such that the frequency signal FG is synchronized with the master clock signal, that is, it carries out spindle servo control.
The PLL circuit 12 generates a recording clock signal based on the master clock signal. The recording signal generation circuit 13 includes a data generation portion 20, an ECC block generation circuit 21, a random value generator 22, a timing circuit 23, a switching circuit 24, a modulator 25, and a synchronization adding circuit 26. The data generation portion 20 outputs information data (main data) to be recorded and address data corresponding to the information data. The ECC block generation circuit 21 outputs sector data adopted to ECC (error correction code) blocks based on the information data and the address data. The random value generator 22 generates random data for linking regions. The timing circuit 23 generates a timing signal for each ECC block in response to the recording clock signal. The switching circuit 24 selectively outputs one of information data in the ECC block and the random data in accordance with the timing signal. The modulator 25 performs 8-16 modulation for data output from the switching circuit 24. The synchronization adding circuit 26 adds a synchronization code having a 14T synchronization pattern to the modulated data so as to output a recording signal. The main controller 18 controls the components 20 to 26 inside the recording signal generation circuit 13 in synchronization with the output clock of the PLL circuit 12.
The optical modulator 14 modulates laser light in accordance with the recording signal output from the recording signal generation circuit 13, and supplies the modulated laser light to a recording actuator 15. The recording actuator 15 irradiates the laser light onto the recording portion of the original recording disk 1 rotated by the spindle motor 16, thus carrying out exposure.
As shown in
The following is an explanation of the operation of the original disk recording apparatus according to the present invention.
Based on information data and address data to be recorded, the ECC block generation circuit 21 successively produces and outputs a data pieces of 91 bytes.
In the DVD format, one ECC block has sixteen sectors, as shown in
The data pieces are supplied via the switching circuit 24 to the modulator 25. After having been subjected to 8-16 modulation, the data pieces are supplied to the synchronization adding circuit 26. The synchronization adding circuit 26 adds a synchronization code (32 bits) including a 14T synchronization pattern to the data pieces having 182 bytes (1456 bits) that have been modulated, to generate a recording signal. The synchronization code is one of eight codes SY0 to SY7, and serves as identification data for identifying data position in each sector.
On the other hand, at the time of the beginning of the recording, the initial value is output from the memory 31 to the eleven D flip-flop circuits 32 to 42 in the random value generator 22. Each of the D flip-flop circuits 32 to 42 outputs a corresponding bit value of the initial value. The output values of the D flip-flop circuits 35 to 42 then serve as the linking region data. After that, whenever a clock signal is supplied, each of the D flip-flop circuits 32 to 42 read the output value of each of the D flip-flop circuits or the adder 44 connected to each input side, and the D flip-flop circuits 35 to 42 output as eight bits (one byte) of linking region data. As the clock is supplied to the clock terminals C of the D flip-flops 32 to 42 for every linking region, for example, the linking region data is renewed at each clock by an adding operation of the adder 44. The linking region data is pseudo data of the above-described data pieces, and consists of 91 bytes. For one linking region, linking region data of 91×2 bytes is generated.
The switching circuit 24 performs a switching operation in response to the timing signal after relaying the data pieces for one ECC block portion from the ECC block generation circuit 21. Thus, the switching circuit 24 becomes a state in which the output data from the random value generator 22 is relayed to the modulator 25. The linking region data is supplied from the random value generator 22 via the switching circuit 24 to the modulator 25. After being subjected to 8-16 modulation, the linking region data is supplied to the synchronization adding circuit 26. The synchronization adding circuit 26 adds a linking region synchronization code (32 bits) including a 14T synchronization pattern to the linking region data of 182 bytes (1456 bits) that have been modulated, to generate a recording signal. The first synchronization code of one row is SYX, and the second synchronization code is SYY. Each of the synchronization codes SYX and SYY has a pattern that is different from the synchronization codes SY0 to SY7, and represents a linking region.
The linking region is formed between ECC blocks (data block regions), and as shown in
The recording signal output from the recording signal generation circuit 13 modulates laser light in the optical modulator 14, and after the modulation, the laser light is supplied to the recording actuator 15. The recording actuator 15 irradiates the laser light onto the recording portion of the original recording disk 1, which is rotated by the spindle motor 16, and thus exposure is performed.
After producing a master disk from the original recording disk 1, optical disks are obtained by duplication with a stamper of the master disk.
Linking regions are formed on each track portion of the optical disk, as shown in
In order to accurately read the information recorded on the optical disk, a tracking control for controlling a reading light beam on a recording track is performed. The phase-difference method can be used as the tracking control for high-density optical disks such as DVD-ROMs. In the phase-difference method, a tracking error signal is generated, which indicates the error between the irradiation position of the light beam and the recording track, in accordance with the difference between the sum signals of the light-receiving signals of opposite light-receiving portions in a photodetector partitioned into four partitions. In the case of the phase-difference method, when the correlation between adjacent track portions is strong, then the tracking error signal includes cross-talk components from the adjacent track portions, so that the tracking control becomes instable. If there are adjacent linking regions in adjacent track portions, the data pattern of those linking regions are different from one another, so that the correlation of the adjacent track portions can be reduced. Thus, it is possible to attain a stable tracking control even when using the phase-difference method for the tracking control.
It is possible that the random value generator 22 uses current address data (which indicates an address of the adjacent data region) as the initial value. That is to say, as indicated by a dashed line in
If the address data is used as the initial value, then the address data may also be recorded together with the random linking region data in the random value generator 22. For example, as shown in
Moreover, as shown in
Furthermore, as a configuration for generating linking region data, it is also possible to use a random value generator 22, a scrambling circuit 29 and a memory 30, as shown in
In the recording apparatus as described above, linking data recording means forms the pseudo data of the adjacent linking regions with recording patterns which are different from each other. In the optical recording medium, the recording patterns of pseudo data of linking regions that are located on adjacent track portions of a track are different from one another. Thus, it is possible to provide read-only non-recordable optical recording media such as DVD-ROMs and recordable optical recording media such as DVD-RWs, with compatibility regarding the recording format. As a result, recording medium players can be designed with a simple configuration. This application is based on Japanese Patent Applications No. 2002-234476 and No. 2003-019159 which are hereby incorporated by reference.
Number | Date | Country | Kind |
---|---|---|---|
2002-234476 | Aug 2002 | JP | national |
2003-019159 | Jan 2003 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
5528569 | Fujiie et al. | Jun 1996 | A |
5850382 | Koishi et al. | Dec 1998 | A |
5949750 | Matsui | Sep 1999 | A |
6067281 | Kobayashi et al. | May 2000 | A |
6115340 | Van Den Enden et al. | Sep 2000 | A |
6191903 | Fujimoto et al. | Feb 2001 | B1 |
6282162 | Tobita et al. | Aug 2001 | B1 |
20010006497 | Shin | Jul 2001 | A1 |
20020054681 | Kuribayashi et al. | May 2002 | A1 |
20020064277 | Kuribayashi et al. | May 2002 | A1 |
20020172123 | Ohmi | Nov 2002 | A1 |
20030161239 | Yamawaki | Aug 2003 | A1 |
20040030983 | Tomita | Feb 2004 | A1 |
20040165504 | Kobayashi | Aug 2004 | A1 |
20040184393 | Kim et al. | Sep 2004 | A1 |
20050088944 | Shoji et al. | Apr 2005 | A1 |
Number | Date | Country |
---|---|---|
1219726 | Jun 1999 | CN |
61-220134 | Mar 1986 | JP |
04-301264 | Oct 1992 | JP |
5-89602 | Apr 1993 | JP |
08-55343 | Feb 1996 | JP |
10-049997 | Feb 1998 | JP |
10-501916 | Feb 1998 | JP |
11-96602 | Apr 1999 | JP |
11-232797 | Aug 1999 | JP |
2002-50136 | Feb 2002 | JP |
2002-133780 | May 2002 | JP |
2002-150698 | May 2002 | JP |
10-0254508 | May 2000 | KR |
WO9818121 | Apr 1998 | WO |
WO 02052558 | Jul 2002 | WO |
Number | Date | Country | |
---|---|---|---|
20040027957 A1 | Feb 2004 | US |