JPH0547110A - Optical disk device - Google Patents

Abstract

(57) [Summary] [Purpose] Recording and playback can be performed by one system without adding an optical system. [Structure] An information signal is compressed by a compression unit 14 every predetermined time. The compressed information signal is temporarily stored in the recording memory 16. The information signal from the recording memory 16 is recorded on the optical disk 11 in the intermittent recording period REC. Period during intermittent recording period REC of information signal
In the MONI, tracking control is performed by the servo control unit 4 so that the light spot is scanned on the same track as the track on which recording was performed immediately before. In the period MONI between the recording periods REC, the reproduction signal is taken out from the optical disk 11 and this reproduction signal is written in the reproduction memory 25 different from the recording memory 16. The reproduction signal is read from the reproduction memory 25, expanded, and the information signal is reproduced by monitor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to recording monitor reproduction of an optical disk device.

[0002]

2. Description of the Related Art There are provided recordable optical disks such as a write-once type and a rewritable type. Of this type of recordable optical disk, data is recorded on an optical disk used as an external storage device such as a computer as needed. Since the recording monitor in this case is recording at any time, even if there is only one optical system, it can be performed by reading the recorded information after recording all the data to be recorded at that time.

[0003]

By the way, although a rewritable CD (compact disc) is known, in the case of this optical disc (for example, a magneto-optical disc), an information signal, for example, an audio signal is recorded in real time.

When recording is performed in real time as described above, when recording monitor reproduction is performed for the purpose of checking the recording state during recording, such as an audio cassette deck, another optical element for reproduction is used. A system was needed, and two optical systems had to be prepared. Therefore, there has been a drawback that a large amount of hardware has to be added in order to realize the recording monitor reproducing function.

In view of the above points, an object of the present invention is to provide an optical disk device capable of recording / reproducing with one optical system.

[0006]

In order to solve the above problems, in the optical disk device according to the present invention, when the reference numerals of the embodiments described later are made to correspond to each other, the compression means for compressing the information signal every predetermined time 14, a recording memory 16 for temporarily storing the compressed information signal, and an intermittent recording period for the information signal from the recording memory 16.
The recording means for recording on the optical disk 11 in REC and the period MONI between the intermittent recording periods REC of the information signals are controlled so that the light spot is scanned on the same track as the track on which the previous recording was performed. Means 4, 10
In the period MONI between the recording periods REC, a means 24 for extracting a reproduction signal from the optical disc 11 and writing the reproduction signal in a reproduction memory 25 different from the recording memory 16, and from the reproduction memory 25. And means for reading the reproduction signal, performing expansion processing, and reproducing the information signal.

[0007]

The information signal is compressed every predetermined time and recorded on the optical disk 11 every predetermined time. Therefore, the recording period REC becomes intermittent. This intermittent recording period REC
In the empty period MONI between the two, the previous recording signal is reproduced from the optical disk 11 and recording monitor reproduction is performed. Therefore, only one optical system is required, almost no additional hardware for recording / reproducing is required, and the device can be made compact.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an optical disk device according to the present invention will be described below with reference to the drawings, taking an audio signal recording device as an example.

FIG. 1 is a block diagram of a recording / reproducing system of the optical disk device of this example. In the figure, reference numeral 1 denotes a rewritable optical disk, for example, a magneto-optical disk, on which spiral recording tracks are formed with a track pitch of 1.6 μm, for example. And this optical disc 1
Is driven to rotate at a constant linear velocity by the spindle motor 2.

In addition, a pregroove for optical spot control (for tracking control) is previously formed on the optical disc 1. In this example, the pregroove is superposed on a wobbling signal for tracking. Absolute time code is recorded (Japanese Patent Laid-Open No. 63-876).
No. 82).

Reference numeral 11 denotes an input terminal, and an analog audio signal of, for example, 2 channels through the input terminal 11 is passed through a low pass filter 12 for band limitation to A
And a sampling frequency of 44.1 kHz is supplied to the A / D converter 13.
Are sampled, and each sampled value is converted into, for example, a 16-bit digital signal. The 16-bit digital signal is supplied to the data compression circuit 14.

In the case of this example, the data compression circuit 14 compresses the input digital data to 1/4. Various methods can be used as this data compression method. For example, an ADPCM (Adapti) with a quantization number of 4 bits is used.
ve Delta Pulse Code Modulation) can be used. In addition, for example, input digital data is divided into a plurality of bands so that the higher the band is, the wider the band becomes, and a plurality of samples (the number of samples should be the same in each band) for each of the divided bands. It is also possible to use a method in which a block is formed, orthogonal transformation is performed for each block in each band, coefficient data is obtained, and bits are assigned to each block based on this coefficient data. The data compression method in this case considers the human auditory perception characteristics to sound, and can perform data compression with high efficiency (Japanese Patent Application No. 1-278).
No. 207).

In this way, the digital data DA (FIG. 2A) from the A / D converter 13 is compressed to 1/4 by the data compression processing in the data compression circuit 14, and the data compressed data da is the recording memory controller. Recording buffer memory 16 controlled by 15
Transferred to. In the case of this example, the buffer memory 16 is a D-RAM having a capacity of 1 Mbit.

The recording memory controller 15 sequentially reads the compressed data da from the buffer memory 16 at a transfer rate that is four times the writing speed, and transfers the read data to the data encoding circuit 17 (FIG. 2B). The recording memory controller 15 is the address controller 7
Writing / reading is controlled by an address control signal from. And the address controller 7
Are controlled by the system controller 10.

In this case, the memory controller 15 controls the memory so that the data stored in the buffer memory 16 is reduced as much as possible during the recording.
For example, when the amount of data in the buffer memory 16 becomes equal to or larger than a predetermined amount (hereinafter, this predetermined amount of data is referred to as one cluster), only one cluster of data is read from the buffer memory 16 and the predetermined data is always read. Memory control is performed so as to secure a write space of a certain amount or more.

In the data encoding circuit 17, the compressed data da for one cluster transferred from the buffer memory 16 has a sector structure of the CD-ROM (one sector is about 2K.
Byte) data. In this example,
One cluster is composed of a plurality of, for example, 32 sectors (however, on the optical disc, it is set to 37 sectors in consideration of front and rear recording margins). Then, the data encoding circuit 17 performs an error detection / correction encoding process for data, in this example, a CIRC encoding process.

The data from the data encoding circuit 17 is supplied to the EFM encoding circuit 18 and subjected to the EFM encoding process in this example as a modulation process suitable for recording.

The encoded data from the EFM encoding circuit 18 is supplied to the magnetic field head 3 via the magnetic field driver circuit 19. Magnetic field driver circuit 19
Drives the magnetic field head 3 so as to apply a modulation magnetic field according to the recording data to the optical disk 1 (magneto-optical disk). The recorded data on the disc 1 is as shown in FIG. 2C.

In this case, the optical disc 1 is housed in, for example, a cartridge, but when it is loaded into the apparatus, its shutter plate is opened and the disc 1 is exposed from the shutter opening. Then, the rotary shaft of the disk drive motor 2 is inserted and connected to the spindle hole of the optical disk 1, and the disk 1 is rotationally driven at a constant linear velocity. The disk drive motor 2 is controlled at a constant linear velocity by a servo control circuit 4 described later.

The magnetic field head 3 faces the disc light 1 exposed from the shutter opening of the cartridge. An optical head 5 is provided at a position facing the surface of the optical disk 1 opposite to the surface facing the magnetic field head 3. The magnetic field head 3 and the optical head 5 are both configured to be movable along the radial direction of the optical disc 1.

The optical head 5 is provided with a laser light source as a light source, and the laser output power of this laser light source is controlled by a control signal from the optical power controller 6, and in the recording period REC, the recording track is larger than that during reproduction. A laser beam with a constant power is irradiated. By this light irradiation and the modulation magnetic field by the magnetic field head 3,
Data is recorded on the optical disk 1 by thermomagnetic recording. At this time, as shown in FIG. 2C, data is sequentially packed and recorded on the optical disc 1.

During this recording, the optical head 5
Of the output of the absolute time decoding circuit 3 via the RF circuit 21.
0, the absolute time code from the pre-groove of the optical disc 1 is extracted and decoded. Then, the decoded absolute time information is supplied to the data encoding circuit 17, inserted into the recording data as absolute time information (absolute address), and recorded on the optical disc 1. The absolute time information from the absolute time decoding circuit 30 is also supplied to the system controller 10 to recognize the recording position and the recording monitor reproduction position recognition described later.
It is used for recognizing the scanning position of the light spot on the optical disc 1.

In this case, as shown in FIG. 2B, when viewed over time, one cluster of audio data is compressed and recorded on the optical disc 1 in intermittent recording periods REC.

As described above, since data is recorded intermittently even in real time, it is not necessary to set the recording state in the period MONI between the recording periods REC and REC. Therefore, in the present invention, the recording monitor reproduction is performed using MONI during this period.

That is, in the case of this example, the system controller 10 switches the apparatus from the recording mode to the reproduction mode when the recording in the intermittent recording period REC is finished and the period MONI after that is reached, and the optical power controller 6 is turned on. The output power of the laser light source of the optical head 5 is controlled and lowered for reproduction.

Then, the signal from the multi-divided detector of the optical head 5 in this period MONI is supplied to the RF circuit 21, from which a focus error, a tracking error and a reproduction signal are obtained. That is, the RF circuit 21
Forms a tracking error signal by using the light detection output of the change of the reflected laser beam from the wobbling track for tracking servo provided on the disk. The tracking error signal is also used during recording.

Further, the received beam spot shape on the multi-divided detector is detected by the signal from the multi-divided detector of the optical head 5, and the RF circuit 21 also outputs the focus error signal of the laser beam incident on the optical disk 1. can get.

During the recording monitor reproduction period MONI, the tracking error signal and the focus error signal from the RF amplifier 21 are sent to the system controller 1.
Is supplied to the servo control circuit 4 via 0, and the servo control circuit 4 controls, for example, a tracking control actuator and a focus control actuator of the optical head 5 to perform tracking control and focus control.

At this time, the absolute time decoding circuit 3
The absolute time from 0, that is, the data of the absolute address is supplied to the system controller 10, and the tracking control is performed so that the optical scanning spot scans the track position where the recording is performed immediately before by referring to the data of the absolute address. Is done.

The recorded data recorded immediately before is
The absolute address is referred to and read from the optical disc 1. That is, the rotation of the plane of polarization (Kerr rotation angle) received by the reflected laser beam in the perpendicularly magnetized film of the magneto-optical disk is detected, and a read information signal having a change according to the rotation of the plane of polarization is formed.

Next, the read information signal obtained by the RF circuit 21 is waveform-shaped and binarized to be reproduced data, which is supplied to the EFM decoding circuit 22 and subjected to EFM decoding processing. The output data of the EFM decoding circuit 22 is supplied to the reproduction decoding circuit 23, where error detection and correction processing and the like are performed, and the CD-R.
A process of decoding the data of the OM sector structure into the original data in the compressed state is performed.

The output data (for one cluster) of the data decoding circuit 23 is transferred to the reproduction buffer memory 25 controlled by the reproduction memory controller 24.
It is written at a predetermined writing speed.

At the time of this monitor reproduction, the reproduction memory controller 24 uses the data decoding circuit 2
Compressed data from 3 to write speed 1
The data is sequentially read at a transfer rate of / 4 times, and the read data is transferred to the data expansion circuit 26. in this case,
The reproduction memory controller 15 writes / writes by the address control signal from the address controller 7.
Readout is controlled.

In the case of this example, the memory controller 24 performs memory control so that the buffer memory 25 stores as much predetermined data as possible over the minimum necessary. For example, each time the empty area of the buffer memory 25 becomes equal to or larger than one cluster, data is written from the circuit 23, and memory control is performed so that a read space of a predetermined data amount or more is always secured.

In the data decompression circuit 23, the ADPCM data is subjected to an inverse conversion process from the data compression process at the time of recording,
It grows 4 times.

The digital audio data from the data expansion circuit 26 is supplied to the D / A converter 27,
It is converted back to a 2-channel analog audio signal and output from the output terminal 29 through the low pass filter 28.
To be monitored.

During the period MONI, it is not necessary for the optical head 5 to scan the immediately preceding recording track for monitor reproduction, and when reading of the signal for recording monitor reproduction from the optical disc 1 is completed. The recording pause state is set to wait for the next recording.

Further, in this case, the reproduction system EFM decoding circuit 22 and the data decoding circuit 23 are arranged in the recording period REC.
In (1), muting is performed by the muting signal from the system controller 10 so that the audio signal is not reproduced.

As described above, according to the present invention, even when recording is performed in real time, recording monitor reproduction can be performed by one optical system.

In the above example, the recorded data immediately before is reproduced by the monitor, but the recorded data may not be the recorded data immediately before.

FIG. 3 shows a flowchart of recording monitor reproduction. In step 101, the data da (n) of the nth cluster is recorded in the recording buffer memory 16.
If it is determined that the data has been written, the process proceeds to step 102 and the data da (n) is read from the buffer memory 16. Then, the process proceeds to step 103 and
The data da (n) is recorded on the optical disc 1 in the REC.

Next, when it is judged in step 104 that the recording has ended and the period MONI after the recording period REC comes, step 1
05, the recorded data da of the n-th cluster
(N) is reproduced, written in the reproduction buffer memory 25, and monitor reproduction is performed. Then, step 106
Then, the process returns to step 101 in preparation for the process of the next recording period REC with n = n + 1.

In the above example, the case of simply performing the monitor reproduction has been described. However, the data of the recording period REC is temporarily stored until the monitor reproduction is completed, and the monitor reproduction reproduces the reproduced data in the data decoding circuit 23. When an error that cannot be corrected is detected,
The temporarily stored recording data makes it possible to instantly redo recording.

When an error that cannot be corrected is generated in the reproduced data by the monitor reproduction, the temporarily stored recording data is stored in another memory together with the information of the absolute address (the information of the absolute address in which the error is generated is separately stored. It may be stored), and after the recording is completed, the data at the position indicated by the absolute address where the error has occurred is stored, and the data can be recorded again.

In the above example, it goes without saying that the recording buffer memory 16 and the reproducing buffer memory 25 can use the same memory if they have different memory areas.

The present invention is not limited to the above examples, but can be applied to all optical disk devices as long as they are optical disk devices that compress and record data in real time.

[0047]

As described above, according to the present invention, in an optical disc apparatus which compresses data and records information in intermittent periods, only one optical system is used during the intermittent recording periods. The recording monitor reproduction can be performed by utilizing the period of. Therefore, since only one optical system is required, it is possible to provide an optical disc device having a recording / monitoring reproducing function with a small device.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of an optical disk device according to the present invention.

FIG. 2 is a diagram for explaining the operation of the example of FIG.

FIG. 3 is a flowchart of an example of the operation of the present invention.

[Explanation of symbols]

 1 Optical Disc 4 Servo Control Circuit 5 Optical Head 6 Optical Power Controller 14 Data Compression Circuit 16 Recording Buffer Memory 25 Playback Buffer Memory 26 Data Expansion Circuit

Claims (1)

[Claims] 1. A compression means for compressing an information signal every predetermined time, a recording memory for temporarily storing the compressed information signal, and information for the predetermined time from the recording memory. Recording means for recording a signal on an optical disc during an intermittent recording period, and a period between the intermittent recording period of the information signal,
Means for controlling the light spot to scan the same track as the track on which recording was performed before the period, and a reproduction signal of the information signal for the predetermined time from the optical disc during the period between the recording periods. An optical disk device comprising: means for taking out and writing the reproduction signal in a reproduction memory different from the recording memory; and means for reading the reproduction signal from the reproduction memory, performing expansion processing, and reproducing the information signal.