JP2801633B2 - Disk unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention reproduces a disc having an ultra-high sound range by separately recording left and right channel signals on both sides of the disc, respectively. The present invention also relates to a reproducing apparatus and a manufacturing apparatus for a disk to be manufactured.

(Prior Art) Compact discs (CDs) are characterized as digital audio discs, in which the dynamic range and distortion are significantly improved as compared to conventional records, have excellent sound quality, and are compact. It is widespread.

Compact discs are used to process left and right 2 channel signals.
20kHz audible frequency band using 44kHz sampling frequency
, And high-density recording can be performed for 60 minutes to 75 minutes on one side.

Compact discs use left and right channel signals to be recorded, for example, EFM (Eight to Fourteen Modulation).
Using modulation, 588 bits consisting of data bits and channel bits as shown in FIG. 4 are recorded as one frame. The bit rate in this case is about 1.936Mb /
s. Since the compact disc is recorded in such a signal format having 588 bits per frame, signals of two channels on the left and right sides can be recorded only in the sound range up to 20 kHz.

By the way, it is generally said that human hearing does not respond to sounds above 20kHz, but even sounds above 20kHz are transmitted to the brain through the skin and ear bones near the ears, and music containing ultrasonic waves above 20kHz It is known that when listening to, alpha waves increase in brain waves.

(Problems to be Solved by the Invention) With a conventional compact disc, signals of two channels on the left and right can be recorded only up to a sound range of 20 kHz.
For example, as described above, there is a demand to further increase the treble frequency range to, for example, 40 kHz to increase the α-wave.

The present invention has been made in view of the above, and it is an object of the present invention to reproduce a disk having an increased high frequency range by recording left and right channel signals separately on one and the other surface of the disk. And a disk reproducing apparatus and a manufacturing apparatus for manufacturing the disk.

[Structure of the Invention] (Means for Solving the Problems) A first invention is to separately output signals while rotating one disk storing the right channel signal on the front side and the left channel signal on the back side. A disk device for reading and reproducing data, wherein signals of right and left channels recorded on a front surface and a back surface of a rotating disk, respectively,
Left and right channel reading means for simultaneously reading out the information part and the error code part as one frame, respectively, and a signal of double frequency by EFM demodulating the left and right channel signals respectively read by the left and right channel reading means. And a left and right channel signal amplifying means for amplifying and outputting the left and right channel signals demodulated by the left and right channel signal demodulating means, respectively. .

A second invention is a disk device for recording a left channel signal on the back side of one master disc and recording a right channel signal on the front side of the disc, wherein the left channel signal to be recorded and the right Input signal converting means for digitally converting the information part and the error code part into one frame after removing a signal having a frequency equal to or higher than the combined frequency of the channel signal, and the left and right channel data from the input signal converting means. Left and right channel modulation means for performing EFM modulation by interpolation processing, respectively, the left channel disc master and the right channel disc while optically controlling left and right channel data from the left and right channel modulation means, respectively. A left and right disk master rotating means for rotating the master in synchronization with each other; A laser beam for recording left and right channel data from the left and right channel modulating means is output to the left and right channel disc masters rotating in synchronization with the right and left disc rotating means, and the tracks are output to tracks. And a means for generating data.

(Operation) In the first invention, when each signal on the back side and the front side of one disk is read, the left channel on the back side and the right channel signal on the front side are each regarded as one frame with the information part and the error code part as one frame. Each of them is read out, demodulated and amplified by EFM modulation and output.

Further, in the second invention, when recording signals on the front and back of one master disc, one frame is composed of an information section and an error code section and is divided into a left channel and a right channel.

Then, the signal of the left channel is EFM-modulated, the laser beam is optically modulated by the modulation signal of the left channel, and is irradiated to the back side of the disc master through the optical system for the left channel for recording.

At the same time, the signal of the right channel is EFM-modulated, and the laser beam is optically modulated by the modulation signal of the right channel, and is irradiated to the front side of the master disc via the optical system for the right channel for recording.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a disk reproducing apparatus according to one embodiment of the present invention. The disc reproducing apparatus shown in FIG. 1 records the signal of the left channel of the two left and right channels on the back surface 1B which is one surface of the disc 1, and the signal of the right channel on the front surface 1U which is the other surface of the disc 1.
Using one disc 1 recorded on the
The left and right channel signals recorded on both sides 1B and 1U of the disc 1 are separately reproduced.
Disc reproduction control unit 3B for reproducing the left channel signal recorded on the back surface 1B of the disc 1, a disk front reproduction control unit 3U for reproducing the right channel signal recorded on the front surface 1U of the disc 1, and both control units 3B, 3U Common control unit 5 for commonly controlling
It is composed of The left and right channel signals recorded on the back surface 1B and the front surface 1U of the disk are recorded, for example, by EFM modulation.

The common control unit 5 includes a motor 7 for driving the disk 1 to rotate.
And a rotation control unit 11 for controlling the motor 7, a microcomputer 29 and a memory 31 for performing an error detection / correction interpolation process described later, and other various controls, and an operation display unit 33. The operation display section 33 has operation buttons, display lamps, and the like, performs various operation controls via the microcomputer 29, and displays a state or the like generated by the various controls.

Disc backside playback controller 3B and disc frontside playback controller
3U has the same configuration, and irradiates the incident light 9a to the back surface 1B or the front surface 1U of the disk 1 which is rotated by the motor 7 of the common control unit 5, and reflects each reflected light 9b from the back surface 1B or the front surface 1U of the disk. It has an optical system 9 for optically reading out signals recorded on the back surface 1B or the front surface 1U of the disk 1 respectively. Each optical system 9 is controlled by the feed control unit 13 to move the disk 1 in the radial direction, and the trace control unit 15 performs focusing and tracking control on each surface of the disk 1. Each modulation signal read from the back surface 1B or the front surface 1U of the disk 1 read by each optical system 9 is supplied to the RF lamp / PLL circuit unit 17 and amplified, and the clock is reproduced. Supplied.
Each demodulation circuit 19 demodulates, for example, a signal which has been read from the back surface 1B or the front surface 1U of the disk 1 and remains EFM modulated, converts the signal into data bits, and supplies the data bits to the data control / interpolation circuit 21. Each data control / interpolation circuit section 21 has an error correction section 23
At the same time, the data demodulated by the demodulation circuit 19 is subjected to error data detection / correction interpolation processing and supplied to the D / A converter 25. The signal subjected to the error detection and correction interpolation processing in each data control / interpolation circuit unit 21 is converted into an analog signal by a D / A converter 25, amplified by an audio amplifier 27 and output, and output from a speaker or the like (not shown). You.

The disc 1 used in the disc reproducing apparatus configured as described above has left and right channel signals on the back side.
1B and the front surface 1U are separately recorded. In this case, as shown in FIG. 2, the back surface 1B and the front surface 1U of the disk 1 need only record only the left or right channel signals, respectively. Since it is not necessary to record the channel signal on only one side of one disk, the signal recording format in the case of the EFM modulation is 588 bits per frame of the conventional signal format shown in FIG. As shown in FIG. 2, 306 bits, which is about half, may be used. Therefore, on the back surface 1B and the front surface 1U of the disk 1, a signal in a high sound frequency range up to 40 kHz, which is about twice as high as that of the conventional 20 kHz, can be recorded. Note that the bit rate in this case is about 1.997 Mb / s.

The disk reproducing apparatus shown in FIG. 1 configured as described above records the disk 1 in which the left and right channel signals are recorded on the back surface 1B and the front surface 1U via the motor 7 of the common control unit 5 as described above. The disc 1 is rotated under the control of the rotation control unit 11 and is controlled to be on a desired position on the back surface 1 and the front surface 1U of the disc 1 by the control of each feed control unit 13 of the disc backside reproduction control unit 3B and the disc front side reproduction control unit 3U. Each of the incident light 9a from each of the optical systems 9 for the left and right channels is irradiated while focusing and tracking are controlled by each trace control unit 15, and each reflected light 9b from the back surface 1B and the front surface 1U of the disk 1 is applied to each optical system. After being detected and read by the system 9, the read signals from the back 1 B and front 1 U of the disk 1 are amplified and clock-reproduced via the respective RF amplifier / PLL circuit units 17. Each demodulation circuit 19 demodulates, and further performs error data detection / correction interpolation processing in each data control / interpolation circuit section 21 and each error correction section 23, and then converts the analog signal of the left and right channels in each D / A converter 25. The signal is converted, amplified by the audio amplifier 27, and output as left and right channel signals from a speaker (not shown) or the like.

FIG. 3 is a block diagram showing a configuration of a disk manufacturing apparatus according to another embodiment of the present invention. The disk manufacturing apparatus shown in the figure records the left channel signal of the two left and right channels on the back surface 41B of the master disk 41 and the right channel signal on the front surface 41U of the master disk 41 for each channel. The disc back side recording control unit 43B records the left channel signal on the back side 1B of the disc master 41, and the right channel signal is recorded on the front side 1U of the disc master 41. And a common control unit 45 that controls both the control units 43B and 43U in common.

The common control unit 45 includes a motor 73 that rotationally drives the master disc 41, a rotation control unit 99 that controls the motor 73, a microcomputer 91 and a memory 93 that perform various control operations and overall control operations, and an operation display unit. 95 and an argon laser 97. The operation display unit 95 has operation buttons, display lamps, and the like, performs various operation controls via the microcomputer 91, and displays a state or the like generated by the various controls. The argon laser 97 outputs a laser beam for recording a signal on the back surface 1B and the front surface 1U of the disk master 41.

The disk back side recording control unit 43B and the disk front side recording control unit 43U have the same configuration, and the motor 73 of the common control unit 45
Back 1B and front 1U of the master disc 41 rotated by
Has an optical system 63 for recording left and right channel signals, respectively. The optical system 63 is controlled to move in the radial direction of the disk master 41 by a radial feed motor 85 via a radial feed servo control unit 87 while being controlled for focusing and tracking by a trace control unit 89.

Also, audio input signals for the left and right channels to be recorded on the back surface 1B and the front surface 1U of the disc master 41,
Each is supplied to each low-pass filter 47 of the disk backside recording control unit 43B and the disk front side recording control unit 43U,
The signal of 40 kHz or more is cut by each low-pass filter 47 and supplied to each sample-and-hold circuit 49, and is supplied from each sample-and-hold circuit 49 to each A / D converter 51 to be converted into a digital signal. The digital signals for the left and right channels from each A / D converter 51 are subjected to error detection and correction interpolation processing in each data control / interpolation circuit unit 53, and are subjected to, for example, EFM modulation in each modulation circuit 55. The left and right channel signals modulated by the respective modulation circuits 55 are respectively supplied to the respective PLL circuits 5
The signal is supplied to each optical modulator 59 and the trace control unit 89 via. Each optical modulator 59 optically modulates the recording laser beam from the argon laser 97 of the common control unit 45 with each modulation signal from each PLL circuit 57, and outputs each optically modulated signal from the beam splitter 61 to the optical system. 63 concave lens 67,
Irradiate onto the back surface 1B or the front surface 1U of the disc master 41 via the recording lens 69, respectively.
Alternatively, left and right channel modulation signals are recorded on the surface 1U. And in this case,
The focus control of the laser beam irradiated on the back surface 1B or the front surface 1U of the disc master 41 is performed by the focus servo control unit 65 of the optical system 63, and the radial feed servo control unit 87 and the trace are also transmitted via the radial feed motor 85. The control unit 89 performs position control and tracking control of the disk master 41 in the radial direction. Each of the focus servo controllers 65 includes a He-Ne laser 75, a beam splitter 77 that shunts the laser beam from the He-Ne laser 75, and a beam splitter 77.
A concave lens 79 and a reflection mirror 71 for irradiating the back surface 1B or the front surface 1U of the master disc 41 via the recording lens 69 of one laser beam shunted by the laser beam splitter 77;
Detector 81 that detects the other laser beam from
And the recording lens 69 in response to the output signal of the photodetector 81.
And a lens control system 83 for controlling

The disk master 41 used for recording in the disk manufacturing apparatus configured as described above has a back surface 1B and a front surface 1U.
It is only necessary to record only the left and right channel signals separately in the reproducing apparatus of FIG. 1 as described with reference to FIG. 2, and the signals of both the left and right channels are conventionally recorded on one disc. Since it is not necessary to record on only one side, the signal recording format in the case of the EFM modulation is about half as shown in FIG. 2 for 588 bits per frame of the conventional signal format shown in FIG. Close to 3
It becomes 06 bits. Therefore, on the back surface 1B and the front surface 1U of the disk master 41, it is possible to record a signal in a high sound frequency range up to 40 kHz, which is about double that of the conventional 20 kHz.

In the disk manufacturing apparatus of FIG. 3 configured as described above, the disk master 41 is recorded on the back surface 1B and the front surface 1U of the disk master 41 while rotating the disk master 41 via the motor 73 under the control of the rotation control unit 99. The low-pass filters 47 of the disk back side recording control unit 43B and the disk front side recording control unit 43U respectively
, Each sample and hold circuit 49, each A / D
After passing through a converter 51 and each data control / interpolation circuit unit 53, each modulation circuit 55 performs EFM modulation and converts it to a channel bit, and supplies it to each optical modulator 59 via each PLL circuit 57, and outputs Argon laser by each modulation signal in the device 59
The laser beam from 97 is light-modulated, and this light-modulated laser beam is irradiated on the back surface 1B and the front surface 1U of the left and right master disks 41 via the beam splitter 61 and the optical system 63, thereby forming the master disk 41. Left and right channel signals are recorded on the back surface 1B and the front surface 1U, respectively.
In this recording operation, each radial feed motor
A position control and a tracking control of the disk master 41 in the radial direction are performed by 85, and a focusing control is performed by the focus servo control unit 65.

In the manufacture of the disc shown in each of the above embodiments, the method of forming the optical system grooves on the back surface and the front surface is reverse winding. It is necessary to synchronize the start point of the recording operation in this reverse winding as much as possible. The data can be aligned by correcting and synchronizing the portions.

Further, in each of the above embodiments, the case of EFM modulation has been described as a modulation method, but the present invention is not limited to this, and other modulation methods may be used. Furthermore, although the description has been given of the case of the optical system as the reproducing system, the present invention is similarly applicable to a capacitance system and a piezoelectric system.

[Effects of the Invention] As described above, according to the first invention, when reading out the signals on the back side and the front side of one disc, the left side channel on the back side and the right channel signal on the front side are respectively read from the information section. And the error code section are read out as one frame, respectively, EFM-modulated, demodulated, amplified and output.

For this reason, on one disk, even if the data stored per frame on both the front and back is half of the conventional data, the obtained signal will be a signal in a double frequency band. For example, conventionally, 588 bits per frame is 2 bits.
Although it was 0 KHZ, the present invention makes it possible to obtain twice 40 KHZ even with about 306 bits, which is about half.

Further, according to the second invention, when recording signals on the front and back of one master disc, one frame is composed of an information section and an error code section, and is divided into a left channel and a right channel.

Then, the signal of the left channel is EFM-modulated, the laser beam is optically modulated by the modulation signal of the left channel, and is irradiated to the back side of the disc master through the optical system for the left channel for recording.

At the same time, the signal of the right channel is EFM-modulated, and the laser beam is optically modulated by the modulation signal of the right channel, and is irradiated to the front side of the master disc via the optical system for the right channel for recording.

For this reason, even if it is one disk, the data to be stored is two frames on the front and back, and as a result, a signal in a double frequency band can be recorded.

For example, a signal of 40 KHZ, which is twice as large as 306 bits, can be recorded.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a disk reproducing apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram showing signal formats recorded on left and right disks reproduced by the reproducing apparatus of FIG. FIG. 3 is a block diagram showing a configuration of a disk manufacturing apparatus according to another embodiment of the present invention, and FIG. 4 is a diagram showing a signal format recorded on a conventional disk. 1 Disc 3B Disc backside playback control unit 3U Disc backside playback control unit 5,45 Common control unit 41 Disc master 43B Disc backside recording control unit 43U Disc frontside recording control unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G11B 20/10 321

Claims (2)

(57) [Claims] 1. A disk device for reading and reproducing signals separately while rotating one disk storing a right channel signal on a front surface and a left channel signal on a back surface, wherein the rotating disk has a front surface. And left and right channel reading means for simultaneously reading out the information part and the error code part as one frame respectively from the right and left channel signals recorded on the back and the left and right channel reading means, respectively. Left and right channel signal demodulation means for respectively performing EFM demodulation of the left and right channel signals obtained to obtain a signal of double frequency, and amplifying the left and right channel signals demodulated by the left and right channel signal demodulation means, respectively. And left and right channel signal amplifying means for outputting Disk apparatus. 2. A disk device for recording a left channel signal on the back side of one disc master and recording a right channel signal on the front side of the disc, wherein the left channel signal to be recorded and the right channel signal are recorded. Input signal converting means for digitally converting the information part and the error code part into one frame after removing a signal having a frequency equal to or higher than the combined frequency of the signals of the left and right channels from the input signal converting means. Left and right channel modulating means for performing EFM modulation by interpolation processing, respectively, while optically controlling left and right channel data from the left and right channel modulating means, respectively, for the left channel disc master and for the right channel Left and right disc master rotation means for rotating the master discs in synchronization Outputting a laser beam for recording left and right channel data from the left and right channel modulating means on a left channel and right channel disc master rotating in synchronization with the left and right disc rotating means. Means for generating data on tracks by means of a disk drive.