JP2768546B2 - Compact disk duplicator - Google Patents

Description

The present invention relates to a compact disk copying apparatus,
In particular, the present invention relates to a device capable of duplicating a compact disc without using an EFM encoder and a subcode encoder.

2. Description of the Related Art FIG. 2 shows a configuration of a conventional apparatus for reproducing a compact disk using a disk recording apparatus, for example, a CDWO (write-once) apparatus.

The CD playback device receives a command of the copy start position and the copy start timing from the system control circuit of the CDWO device, and
And outputs a digital signal from the digital out terminal, or outputs an analog signal from the analog out terminal.

The rotation speed of the disk motor of the CD reproducing device is controlled by comparing the oscillation frequency of the reference oscillator in the CD reproducing device with the highest frequency extracted from the reproduced EFM signal.

The CDWO device performs tracking servo and focus servo with a wobble signal obtained from a pre-groove (waveform track) of a WO disk, and compares the frequency of a wobble signal with the frequency of a reference oscillator in a CLV servo circuit. The rotation speed of the motor is controlled.

Further, a signal FM-modulated into a wobble signal is demodulated and decoded by an ATIP decoder to obtain an ATIP (absolute time) code.

The ATIP code is input to a subcode encoder to generate a subcode.

The system control circuit instructs the laser modulator and the EFM encoder on the recording start timing, and instructs the tracking servo circuit on the recording start position and the recording start timing to copy the disk.

When a digital signal of a CD playback device is used, the digital signal is converted into a data structure by a digital interface, is input to an EFM encoder together with a subcode output from a subcode encoder, and is converted to an EFM signal output from the EFM encoder. The laser output is modulated and recorded on a WO disk.

When an analog signal from a CD playback device is used, the analog signal is converted to a digital signal by an A / D converter, and the EF is output together with the subcode output from the subcode encoder.
Input to M encoder and output from EFM encoder
The laser output is modulated by the EFM signal and recorded on the WO disk.

[Problem to be Solved by the Invention] According to the above-mentioned conventional device, there is a problem that a complicated circuit such as an EFM encoder and a sub-code encoder is required, and the device becomes expensive.

The present invention has been made to solve the above problems, and has as its object to provide a compact disk duplication apparatus having a simple configuration without requiring an EFM encoder or a subcode encoder.

[Means for Solving the Problems] A compact disk duplicating apparatus according to the present invention comprises a reference oscillator, a PLL circuit for generating a master clock based on an output signal of the reference oscillator, a signal obtained from a compact disk, and the master clock. A compact disk playback device that controls the disk motor by comparing the EFM signal and outputs an EFM signal synchronized with the master clock, a waveform shaping circuit that shapes the waveform of the EFM signal, and a time axis indicating the output of the waveform shaping circuit. A timing setting circuit for correction, a disk recording device for controlling a disk motor by comparing a wobble signal obtained from the CDWO disk with an output signal of the reference oscillator, and a demodulating and demodulating ATIP signal obtained from the CDWO disk. A signal from an ATIP demodulation circuit that outputs one time information and the EFM signal are demodulated and A second time information is inputted extracted from the code signal, TO while rotating the other as a pause state while the TOC start position of the compact disc player and the disc recorder under the control of the disc motor
A control circuit that obtains the first or second time information from a position before the C head position and releases the pause state when the TOC head position is reached and starts reproduction and recording from the TOC head position of both disks; and And records information of a compact disc on a CDWO disc without demodulating and modulating a recording signal.

[Operation] The rotation speed of the disk motor of the CD reproducing apparatus is controlled by comparing the oscillation frequency of the reference oscillator with the highest frequency extracted from the reproduced EFM signal.

The CDWO device performs CLV control of the disk motor by comparing the frequency of the wobble signal obtained from the pregroove of the WO disk with the frequency of the reference oscillator.

In this way, the CD playback device and the CDWO device use the common reference oscillator to control the disk motor rotation speed. Therefore, if the playback and recording start positions match, the playback and recording positions of the playback CD and the recorded CDWO disk match. If the EFM signal obtained from the reproduced CD is waveform-shaped and the timing is set, the signal is laser-modulated and recorded on a CDWO disk, whereby a CDWO disk on which the same signal as the reproduced CD is recorded can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

 FIG. 1 is a block diagram showing an embodiment of the present invention.

In the figure, reference numeral 1 denotes a reference oscillator, which supplies a reference signal to a PLL circuit 2 that generates a master clock of a CD reproducing device 3 and a reference signal of a waveform shaping timing setting circuit 4.

The master clock generated by the PLL circuit 2 (4.3
218 MHz) and the highest frequency extracted from the reproduced EFM signal, thereby controlling the rotation speed of the disk motor of the CD reproducing device 3.

The EFM signal output from the CD reproducing device 3 is waveform-shaped by the CMOS amplifier of the waveform shaping timing setting circuit 4 and the time axis is corrected. Further, the rising of the EFM signal is delayed by one unit time (1T). The laser beam from the laser modulator 14 is modulated to record a CDWO disk.

On the other hand, in the CDWO device 5, the frequency of the wobble signal obtained from the optical pickup 7 is compared with the oscillation frequency of the reference oscillator 1 by the CLV servo circuit 11, and the rotation speed of the disk motor 8 is controlled.

The light reflected from the pregroove is converted into a current by the light receiving element and amplified by the preamplifier 10, and then supplied to the tracking servo circuit 12 and the focus servo circuit 13 to perform tracking and focusing of the optical pickup 7.

The ATIP decoder 9 of the CDWO device 5 obtains an ATIP code representing an absolute time by demodulating and decoding the FM-modulated wobble signal obtained from the optical pickup 7, and outputs the ATIP code to the control circuit 6.

The control circuit 6 sends a signal to the CD reproducing device 3 in advance, puts the optical pickup in a pause state in accordance with the TOC head position of the optical disk, and reads the ATIP code input from the ATIP decoder 9 while reading the TOW code of the CDWO disk.
A signal is sent to the tracking servo circuit 12 to move the optical pickup 7 to the C recording head position.

When the control circuit 6 detects from the input ATIP code that the optical pickup 7 has reached the TOC recording head position, it sends a signal to the CD playback device 3 to start playback of the optical disk, and sends a signal to the laser modulator 14. Start recording the CDWO disc.

Thereafter, in the CD reproducing device 3 and the CDWO device 5, the disk motor is controlled by the frequency of the common reference oscillator, and normal tracking and focusing are performed, so that reproduction and recording are performed simultaneously.

[Effects of the Invention] As described above, according to the compact disk duplication apparatus of the present invention, a complicated EFM encoder is not required, and an AD converter and a digital interface are not required, so that the manufacturing cost is reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a compact disk copying apparatus according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional technique. DESCRIPTION OF SYMBOLS 1 ... Reference oscillator, 2 ... PLL circuit, 3 ... CD reproducing device, 4 ... Waveform shaping timing setting circuit, 5 ... CDWO device, 6 ... Control circuit, 7 ... Optical pickup,
8: Disk motor, 9: ATIP decoder, 10: Preamplifier, 11: CLV servo circuit, 12: Tracking servo circuit, 13: Focus servo circuit, 14: Laser modulator.

 ────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-2-71457 (JP, A) JP-A-2-91851 (JP, A) JP-A-3-44881 (JP, A) JP-A-4- 134667 (JP, A)

Claims (1)

(57) [Claims] 1. A reference oscillator, a PLL circuit for generating a master clock based on an output signal of the reference oscillator, and controlling a disk motor by comparing a signal obtained from a compact disk with the master clock. A compact disk playback device that outputs an EFM signal synchronized with a waveform shaping circuit that shapes the EFM signal, a timing setting circuit that corrects the output of the waveform shaping circuit on a time axis, and a wobble signal obtained from a CDWO disk. A disk recording device for controlling a disk motor by comparing the output signal of the reference oscillator, a signal from an ATIP demodulation circuit for demodulating an ATIP signal obtained from a CDWO disk and outputting first time information, and The second time information extracted from the subcode signal by demodulating the EFM signal is input, and Obtaining the first or second time information from a position before the TOC head position while rotating one of the compact disk playback device and the disk recording device at the TOC head position and rotating the other under the control of the disk motor. A control circuit for releasing the pause state when the TOC head position is reached and starting reproduction and recording from the TOC head position of both disks, and information of the compact disk on the CDWO disk without demodulating and modulating the recording signal. A compact disk duplicating apparatus characterized by recording information.