JPH06150326A - Disk recordig and reproducing device - Google Patents

Abstract

PURPOSE:To physically and completely erase the stored data on a disk and to erase them at a higher speed than that of the time of recording in the disk recording and reproducing device performing a recording/reproducing, intermittently. CONSTITUTION:When a continuous mode is instructed by an erasing instruction key 18B, an intermittent/continuous recording selection part 16B is set to a continuous recording state and a recording/erasing signal selection part 16C is also set to an erasing signal selection state by a control part 16A. At this time, the device becomes to be in an erasing mode an erasing signal is recorded continuously to the disk 1 by using a magnetic head 14 and an optical head 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intermittent recording / reproducing disc recording / reproducing apparatus capable of completely and rapidly erasing invalid data on a disc.

[0002]

2. Description of the Related Art It has been a long time since a compact disc (CD) was developed as a medium superior to an analog record, but some recording media have been developed during this period. One of them is a mini disk (MD), which can be expected to have the portability of a compact cassette and the operability and sound quality of a CD, and it is drawing attention as an audio recording medium in the future.
Since the MD follows the PCM system similar to that of the CD, but adopts a new audio compression system, it is possible to realize the same high sound quality as the CD with an information amount of about 1/5. Therefore, even a disc having a diameter about half that of a CD can realize a reproduction time comparable to that of a CD.

There are two types of MDs, and a read-only MD that can only be played back uses an optical disk similar to a CD. On the other hand, a recording / reproducing MD capable of recording as well as reproducing uses a magneto-optical disk. The MD player compatible with such two types of MDs is equipped with not only an optical head for recording / reproducing but also a magnetic head for recording. An MD player capable of recording and reproducing MD has a recording mode for writing recording data to a disc and a reproducing mode for reading reproduction data from the disc, and the user selectively selects these modes.

By the way, in order to erase the audio data once recorded on the recording medium, (1) a new audio signal is recorded, (2) an analog or digital silence signal is recorded, (3). There is a method of rewriting the information in the table of contents (TOC) accompanying the recording area to invalidate the data recorded in the corresponding recording area.

[0005]

However, since the methods (1) and (2) described above are basically the operation in the recording mode, the erasing time becomes the same as the recording time, and high-speed erasing cannot be realized. . In order to improve this point, a means such as a bulk eraser used for high speed erasing recorded data on a magnetic tape is also conceivable.
A magnetic head or the like that generates a strong magnetic field required to erase recorded data on a magneto-optical disk such as D becomes expensive and is not suitable for mounting on an MD player or the like.

On the other hand, even if the TOC is edited by the method (3), the recorded data is apparently only erased, and unless the new data is overwritten in the corresponding recording area, the data is physically deleted. It remains on the disc. Ordinary players cannot play back data that has been invalidated by TOC. However, it is possible to play back that portion accidentally or intentionally due to failure, recording medium trouble, device modification, etc. It is not preferable from the viewpoint of the above. The present invention improves on the above points,
It is an object of a disc recording / reproducing apparatus for intermittently recording / reproducing so that recorded data on a disc can be physically completely erased and at a higher speed than at the time of recording.

[0007]

In order to achieve the above object, according to the present invention, there is provided a recording mode for intermittently writing recording data to a disc by using a writing means, and an intermittent reproduction from the disc by using a reading means. It is characterized by comprising a reproduction mode for reading data and an erasing mode for continuously erasing recorded data on the disc by using the writing means.

A second feature of the present invention is a recording mode in which recording data is intermittently written by a magnetic recording head while irradiating a magneto-optical disc with predetermined light from the optical head, and a recording mode in which the optical head is used to record data. A reproduction mode for reading reproduction data intermittently, and a recording signal of the magnetic recording head being turned off or being driven by an erasing signal while irradiating light from the optical head that is substantially the same as or stronger than the recording mode. It has a delete mode for continuously deleting recorded data on the disk.

[0009]

When the invalid data on the disc is to be erased by the disc recording / reproducing apparatus which records / reproduces intermittently, the present invention does not use the normal intermittent recording mode but continuously erases the data. By setting a new erase mode to be performed, it is possible to erase faster than when recording. Moreover, in this erasing mode, not only the TOC is edited but also the erasing operation is actually performed on the recording area, so that it is possible to physically completely erase the invalid data from the disc.

When a magneto-optical disk is used as the disk, it is necessary to erase the data magneto-optically. In this case, when the optical head irradiates the disc with light having substantially the same intensity as or stronger than that in the recording mode, the temperature of that portion rises above the Curie point, the recorded data disappears, and physical erasing is performed. At this time, the recording signal of the recording magnetic head is turned off, or the recording signal is operated so as to record a predetermined erasing signal, whereby the erasing operation of a desired form is performed.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of the essential parts showing the basic configuration of the present invention. In this figure, 1 is a disk as a recording medium, 3 is a recording / reproducing head used in a recording / reproducing mode, 14 is a recording head used in the recording mode,
In the erase mode, the recording / reproducing head 3 and the recording head 14 are used as in the recording mode. This disc recording / reproducing device
It has an intermittent recording mode, an intermittent reproduction mode, and a continuous erasing mode. The intermittent recording mode is instructed by the recording instruction key 18A and the continuous erasing mode is instructed by the erasing instruction key 18B (the instruction key of the reproduction mode is omitted in the drawing. Available).

Control unit 16A, intermittent / continuous recording selection unit 16
B, the recording / erasing signal selection unit 16C is each function of the system controller of the disc recording / reproducing apparatus, and the control unit 16A controls the whole, and the intermittent / continuous recording selection unit 16B.
Selects whether the recording operation is performed intermittently or continuously. The recording / erasing signal selection unit 16C selects whether the signal to be recorded on the disc 1 is a normal recording signal or an erasing signal for erasing. The recording signal is generated by the recording signal generator 2
1 and the erase signal is generated by the erase signal generator 22.

When the intermittent recording mode is instructed by the recording instruction key 18A, the control unit 16A sets the intermittent / continuous recording selection unit 16B to the intermittent recording state and sets the recording / erasing signal selection unit 16C to the recording signal selection state. Set. With this, the recording mode is set, and the recording signal is recorded on the disk 1 intermittently, that is, with the waiting period interposed, using the recording head 14 and the recording / reproducing head 3. Writing is performed intermittently when the writing speed to the disc 1 is faster than the generation speed of the recording signal, for example, when the recording signal is compressed. In such a case, the reading speed becomes faster than the reproducing speed, so that reading from the disc 1 is also performed intermittently.

On the other hand, the control unit 16A controls the erase instruction key 18
When the continuous erasing mode is instructed by B, the intermittent / continuous recording selecting unit 16B is set to the continuous recording state, and
The erase signal selection unit 16C is set to the erase signal selection state.
With this, the erase mode is set, and the erase signal is recorded on the disk 1 continuously by using the recording head 14 and the recording / reproducing head 3, that is, without providing a waiting period. Since the erasing signal is continuously written to the disk 1 without a waiting period, the erasing operation is completed in a much shorter time than when the erasing signal is intermittently written in the recording mode. Moreover, since invalid data is physically deleted instead of editing the TOC, security is high in terms of confidentiality protection.

FIG. 2 is a block diagram of an embodiment in which the present invention is applied to an MD type disc recording / reproducing apparatus. In the figure, 1 is a magneto-optical disc capable of recording and reproducing,
Reference numeral 2 is a spindle motor for rotating the disk at a constant linear velocity, and 3 is a light for optically reading information from the disk 1 (detecting a difference in Kerr rotation angle) or writing information magnetooptically on the disk 1. A pickup 4 is a feed motor for moving the pickup 3 in the radial direction of the disk 1, a reference numeral 5 is a radio frequency (RF) amplifier for amplifying the output of the pickup 3, a reference numeral 6 is a rotation control of the spindle motor 2, a feed control of the feed motor 4 and This is a servo control unit for focus / tracking of the pickup 3.

The read system of this MD player includes a decoder section of an encoder / decoder 7 for decoding (demodulating) the output of the high frequency amplifier 5, an address decoder 8 for detecting an address being reproduced from the output of the high frequency amplifier 5, and an encoder. / Memory 9 for temporarily storing the decoded output of the decoder 7 and its controller 10, the expansion unit of the audio compression / expansion unit 11 for expanding the output of the memory 9, and this audio compression / decompression unit.
D / A for converting the expanded output of the expansion unit 11 into an analog signal
It is composed of a conversion unit 12. Encoder / decoder 7
Is an EFM (eight to fourteen modula) modulation method.
(CItion), and CIRC (cross in
terleave reed-solomon code).

The writing system of this MD player includes an A / D converter 13 for converting an analog signal into a digital signal,
An audio compression / decompression unit 1 for compressing the converted digital signal so as to remove components unnecessary for audio signal reproduction.
1 compression unit and memory 9 for temporarily storing the compressed signal
And its controller 10, an encoder section of the encoder / decoder 7 for encoding (modulating) the output of the memory 9, a recording head (magnetic head) 14 for writing the signal encoded by this encoder section to the disk 1 and its head drive. And the circuit 15. Reference numeral 16 is a system controller for controlling the whole, 17 is a display unit for displaying various information, and 18 is a plurality of operation keys for giving various instructions. The operation keys 18 include the recording instruction key 18A and the reproduction instruction key shown in FIG. 1, but the erase instruction key 18B of the present invention is shown separately.

The above-mentioned MD player is based on a CD player, to which voice compression technology, seismic resistance technology, user recording function and the like are added. The voice compression performed by the voice compression / decompression unit 11 is performed by thinning out unnecessary data by utilizing the human hearing characteristics. For example, ATRAC (Adapti
A compression technology called ve Transform Acoustic Coding) uses the minimum audible limit characteristics of human beings and the masking effect to realize about 5 times information compression. The decompression unit for decompressing the compressed data synthesizes the decoded outputs of the encoder / decoder 7 and sequentially reproduces the digital waveform. With this method, when the level is changed in 16-bit steps and the sampling frequency is expressed as 44.1 kHz, the quality equivalent to the signal is reproduced. In order to perform this data compression / expansion, a buffer memory 9 having a corresponding capacity is required on the signal processing circuit.

One of the features that enhances the portability of the MD player is the seismic resistance technology that copes with "sound skipping". This is realized by utilizing the difference between the read speed of the pickup 3 and the transfer speed of data input to the audio compression / decompression unit 11, and using the memory 9 as a data buffer. That is, the read speed of the pickup 3 is as high as 1.4 Mb (megabit) / s, whereas the transfer speed of data input to the audio compression / decompression unit 11 is as low as 0.3 Mb / s. Therefore, using the 1 Mbit memory 9,
The data for about 3 seconds can be stored. Therefore, even if reading from the disc 1 is stopped due to vibration,
If it returns within seconds, the reproduced audio output does not "skip". The memory 9 is also used during writing. In this case, the audio compression / decompression unit 11 outputs 0.3.
The compressed data output at Mb / s is temporarily stored in the memory 9, read out, and transferred to the encoder / decoder 7 at 1.4 Mb / s. Since writing to the disk 1 by the magnetic recording head 14 is performed at 1.4 Mb / s, this writing is intermittent using only a part of the entire processing time.

In the MD player, an optical disk dedicated to reproduction can be mounted on the disk 1, but an MD for recording and reproduction.
With, you can write as well as read. Laser light from the magnetic recording head 14 and the optical head (pickup) 3 is used for writing. For this writing method, a magnetic field modulation method is used in which a laser beam having a constant intensity is applied to the lower surface of the disk 1 and a magnetic field modulated with write data is applied from the upper surface. When erasing invalid data with this MD player, the optical pickup 3 irradiates a laser beam which is substantially the same as or stronger than the recording mode, and at the same time, the recording signal of the magnetic recording head 14 is turned off or the erasing signal is erased. The data in that portion is erased by driving with to overwrite this erase signal. This erase mode is performed in continuous operation. Hereinafter, this point will be described.

FIG. 3 is an explanatory diagram showing the above-mentioned intermittent writing and continuous erasing. In this figure, the horizontal direction is the time axis,
The vertical direction indicates the flow of processing. The top is the transfer rate of 1.4 Mb / s digitized by the A / D converter 13.
When the audio compression unit 11 compresses this audio data, it becomes compressed data with a transfer rate of 0.3 Mb / s shown in the second stage. This compressed data is stored in the memory 9 and EFM.
It reaches the magnetic recording head 14 via the encoder 7 and is written on the disk 1 at a speed of 1.4 Mb / s in terms of audio data as shown in the third row. Therefore, a waiting time longer than one writing time is interposed between the writing. The above is the operation in the intermittent recording mode. On the other hand, in the erase mode, as shown at the bottom, the erase signal is continuously 1.4 Mb / s without providing a waiting period.
Is written to disk 1 at a speed of. In such a continuous erasing mode, the time until the erasing is completed is shortened to about 1/5 of that in the recording mode, and high-speed erasing becomes possible.

As the erase signal, a repeating pattern of random data or meaningless fixed data may be used. In the case of MD, the following signals can be used. (1) A signal whose reproduction signal level is sufficiently low during reproduction, eg, a high frequency signal, (2) EFM
In the system, a single frequency in the range of 1T to 11T or a combination signal of a plurality of single frequencies, (3) a signal of (2) in which a prescribed EFM sync exists, and (4) an almost no signal (digital signal) as an audio signal when reproduced. An EFM signal encoded so as to be zero, or equivalent thereto, or almost no analog signal), and (5) a signal which, when recorded, is magnetized substantially uniformly in the direction perpendicular to the disk surface. Also, continuous erasing is possible by turning off the erasing signal. In this case, the magnetic recording head may be mechanically kept away from the disk.

Although the embodiment using the MD as an example has been described above, the present invention is not limited to the MD. That is,
The present invention can be applied to any device that performs intermittent recording as in the MD. The target disk is not limited to the magneto-optical disk. For example, when a phase change disk is used, an optical head that continuously erases the disk may be used.

[0024]

As described above, according to the present invention, in the disc recording / reproducing apparatus for intermittently recording / reproducing, the recorded data on the disc is physically completely erased and at a higher speed than at the time of recording. be able to.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of the present invention.

FIG. 2 is a block diagram of an embodiment in which the present invention is applied to an MD recording / reproducing device.

FIG. 3 is an explanatory diagram showing intermittent writing and continuous erasing.

[Explanation of symbols]

1 ... Disk, 2 ... Spindle motor, 3 ... Optical pickup (optical head), 4 ... Feed motor, 5 ... High frequency amplifier, 6 ... Servo control section, 7 ... EFM encoder / decoder, 8 ... Address decoder, 9 ... Memory, 10 ... Memory controller, 11 ... Audio compression / decompression unit, 12 ... D / A
Converter, 13 ... A / D converter, 14 ... Magnetic recording head,
15 ... Head drive circuit, 16 ... System controller,
16A ... Control unit, 16B ... Intermittent / continuous recording selection unit, 16
C: recording / erasing signal selection section, 17 ... display section, 18 ... operation key, 18A ... recording instruction key, 18B ... erasing instruction key,
21 ... Recording signal generating unit, 22 ... Erase signal generating unit.

Claims (2)

[Claims] 1. A recording mode in which recording data is intermittently written to a disc by using a writing unit, a reproduction mode in which reproduction data is intermittently read from the disc by using a reading unit, and the recording mode is used by the writing unit. A disc recording / reproducing apparatus comprising: an erasing mode for continuously erasing recorded data on a disc. 2. A recording mode in which recording data is intermittently written by a magnetic recording head while irradiating a magneto-optical disc with predetermined light from an optical head, and reproduction data is intermittently read from the disc by the optical head. In the reproduction mode, the recording signal of the recording magnetic head is turned off while irradiating the optical head with substantially the same or stronger light as in the recording mode, or the recording data on the disk is continuously driven by an erase signal. A disc recording / reproducing apparatus, comprising: an erasing mode for erasing and erasing.