摘要:
An optical disc medium 10 having a wobbled track groove 12 includes three wobble patterns including a flat wobble pattern, a positive pulse wobble pattern, and a negative pulse wobble pattern. In the flat wobble pattern, the amplitude of the wobble from the lengthwise direction of the track groove is zero such that the track groove is flat. In the positive pulse wobble pattern, the amplitude of the wobble from the length-wise direction of the track groove is positive such that the track groove is wobbled in a first direction perpendicular to the length-wise direction. Further, in the negative pulse wobble pattern, the amplitude of the wobble from the lengthwise direction of the track groove is negative such that the track groove is wobbled in a second direction opposite to the first direction. Then, three data values can be recorded using three distinctive wobble patterns.
摘要:
An optical disc medium 10 having a wobbled track groove 12 includes three wobble patterns including a flat wobble pattern, a positive pulse wobble pattern, and a negative pulse wobble pattern. In the flat wobble pattern, the amplitude of the wobble from the lengthwise direction of the track groove is zero such that the track groove is flat. In the positive pulse wobble pattern, the amplitude of the wobble from the lengthwise direction of the track groove is positive such that the track groove is wobbled in a first direction perpendicular to the lengthwise direction. Further, in the negative pulse wobble pattern, the amplitude of the wobble from the lengthwise direction of the track groove is negative such that the track groove is wobbled in a second direction opposite to the first direction. Then, three data values can be recorded using three distinctive wobble patterns.
摘要:
The information such as address is to be efficiently formed into wobble components and further the S/N ratio in reproducing the information formed into the wobble components is to be improved. In an optical disc of the present invention, there are recorded in a wobble the address information modulated in accordance with the MSK (minimum shift keying) system and the address information modulated in accordance with a modulation system in which even harmonics signals are added to a sinusoidal carrier signal and in which the polarity of the harmonics signal is changed depending on the sign of the data for modulation.
摘要:
The S/N ratio is improved for recording data to grooves (2-1,2-2) of an optical disc so that as much information as possible can be recorded at the lowest possible frequency band. An optical disc using wobble patterns to record different information has a first groove (2-1) having a first wobble pattern (22) in which one wobble period has a sharp rising edge and a gradual falling edge; and a second groove (2-2) having a second wobble pattern (24) in which one wobble period has a gradual rising edge and a sharp falling edge. Each of the first and the second wobble pattern is represented by a first fundamental and a second harmonic of a Fourier series. The polarity of the second harmonic, which is an even harmonic, of the second wobble pattern is opposite that of the first wobble pattern. A method for manufacturing this optical disc is also provided.
摘要:
In an optical disc, a wobble signal is to be detected by a simple configuration. In the optical disc, the address information, modulated onto a sinusoidal cannier signal by adding even harmonics signals to the sinusoidal carrier signal and by changing the polarity of the harmonics signals, is formed into the wobble signal. In detecting the wobble signal from the optical disc to demodulate the address information, in a method for detecting the wobble signal, an even harmonics signal and data clocks are generated, and the even harmonics signal so generated are multiplied with the reproduced wobble signal. The resulting product signal is integrated every data clock. The sign of the digital information is verified based on the integrated value at an end edge of the data clock.
摘要:
A record carrier (1) has a servo track (4) indicating an information track (9) intended for recording information blocks. The servo track (4) has a periodic variation of a physical parameter at a predetermined frequency, usually called wobble. The servo track has modulated parts for encoding position information according to a predetermined type of modulation. The record carrier includes a management area in which the servo track includes permanent data. The permanent data is encoded using a different type of modulation, but using the variations of the same physical parameter. Direct digital modulation (41) is proposed for the different type of modulation.
摘要:
An ECC block is constituted by RS(248,216,33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are calculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus, the error correction capability in a burst cutting area of an optical disc can be improved.
摘要:
Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.
摘要:
An ECC block is constituted by RS(248, 216, 33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are calculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus, the error correction capability in a burst cutting area of an optical disc can be improved.
摘要:
Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.