JPS6116033A - Rewritable optical recording and reproducing device - Google Patents

Abstract

PURPOSE:To detect the deterioration of recording sensitivity of an optical disk by using a means which records a test signal to a specific track and detects whether the recording level is equal to a prescribed level or not. CONSTITUTION:A specific track is reproduced in a reproduction mode, and the reproduction data 27 is sent to a comparator 24. The comparator 24 compares the test data with the data 27 and delivers a coincidence signal 28 when no coincidence is obtained from said comparison. A counter 23 counts the signals 28 and delivers a bad system signal 29 when the count value exceeds a fixed level N. The test data is recorded and reproduced every time a power supply is started. Then the record data is compared with the reproduction data to detect previously a system fault. Thus it is possible to detect the deterioration of both the erasing sensitivity and the recording sensitivity of an optical disk.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rewritable optical recording and reproducing device that records, reproduces and erases signals by focusing a laser beam into a minute spot light and applying a thermal change to an optical disk. .

Conventional configuration and its problems In recent years, signals have been recorded and reproduced on optical discs by focusing laser light to about 1 μm. In particular, erasable optical recording in which a recording material is deposited on an optical disk, recorded by applying a thermal change using a laser beam, and once the recorded signal is erased by irradiation with a laser beam, a refocusing signal can be recorded and reproduced. A playback device has been proposed. This optical recording and reproducing device has high recording density, low memory cost per bit, high-speed access, and stable recording and reproducing without contact between the optical head and the optical recording medium. It is attracting attention as a new memory medium for the future information society.

As a rewritable optical recording and reproducing method, a method has been proposed in which thermal energy such as laser light is used to cause a reversible change in optical density by transition between an amorphous state and a crystalline state of an optical recording medium. ing.

In other words, when the temperature of an amorphous optical recording medium with low reflectance and high transmittance is raised to near its melting point and then slowly cooled,
It utilizes the phenomenon that an optical recording medium in a crystalline state transitions to a crystalline state with high reflectance and low transmittance, and conversely, when the temperature of a crystalline optical recording medium is raised to 1 near the melting point and then rapidly cooled, it transforms to an amorphous state. Materials that correspond to this include TeGexoy and T
e5nxOy is used, and it is possible to repeatedly record and reproduce signals.

However, currently used or proposed TeGe
xOa, TeSn process 0a Other recording materials cannot necessarily be said to be perfect materials, and deterioration in erasing sensitivity or recording sensitivity is observed due to repeated recording and erasing. Conventionally, there is no means for detecting such deterioration of an optical disc in advance, and since recording and reproduction are performed on a deteriorated disc, there is a problem in that stable reproduction of information is not guaranteed. There is also the problem that information may be lost due to failure of the optical disk device itself.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and it is an object of the present invention to provide an optical recording/reproducing apparatus capable of detecting deterioration in erasing sensitivity or recording sensitivity of an optical disc.

Structure of the Invention The present invention comprises: a signal recording means for recording a test signal on a specific track; a signal erasing means for erasing the test signal recorded on the specific track; and a signal erasing means for erasing the test signal recorded on the specific track; This is a rewritable optical recording and reproducing device, which is equipped with an erasure level detecting means for detecting the erasure level, and a life notification stage that determines that the erasure life of the disk has come and notifies the user when the level of the remaining erasure is equal to or higher than a predetermined level. It is possible to know.

The present invention also provides a signal recording means for recording a test signal on a specific track, a recording level detection means for reproducing the test signal recorded on the specific track and detecting a recording level of the test signal, and a recording level of the test signal. A rewritable optical recording/reproducing device is provided with a life notifying means for determining and notifying that the recording life of a disk has reached a predetermined level or less, and a signal erasing means for erasing the test signal, and detecting deterioration of recording sensitivity. It is something that can be done.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 shows the configuration of a rewritable optical recording and reproducing apparatus in a first embodiment of the present invention.

In Figure 1, 1 is an optical disk, 2 is a laser drive circuit, 3 is a recording/reproducing laser, 4 is a condensing lens, 6 is a wavelength selection filter, 6 is a polarizing beam splitter, 7 is an aperture lens, and 8 is A wavelength. board, 9 mirrors, 10 condensing lenses,
11 is an erasing laser, 12 is a laser drive circuit, 13 is a wavelength selection filter, 14 is a photodetector, 16 is a signal processing circuit, 16 is a recording/erasing gate generation circuit, 17 is a modulation circuit, 1
8 is an encoder, 19 is a demodulation circuit, 20 is a decoder, 2
3 is a counter, 24 is a comparator, and 26 is a test data generation circuit.

The operation of the rewritable optical recording/reproducing apparatus of this embodiment configured as described above will be described below.

The optical disc 1 is a disc made of an optical recording medium,
It is rotating at a constant speed. A spiral or concentric groove designed to function as a guide track that can be detected by the optical tube is formed on this disk, and recording, reproduction, and erasing are performed along this groove. Now, when a certain data 3o is to be recorded, the data 3o is sent by the encoder 18 and modulation circuit 17 to the recording/erasing gate generation circuit 16 as modulated data 32. The recording/erasing gate generation circuit 16 generates a recording/recording gate signal 21 based on the modulated data 32. The laser drive circuit 2 has a wavelength λ
1, a recording light beam 33 is irradiated from the recording and reproducing laser 3 in the section where the recording gate signal is H''.The irradiated recording light is transmitted through the condenser lens 4. Selection filter 5. The beam passes through a polarizing beam splinter 6, changes its direction with a mirror 9, passes through a wavelength plate 8, and is narrowed down to a diameter of 1 μm or less by an aperture lens 7, forming an approximately circular recording spot on the guide track of the optical disc 1. recording is performed by lowering the reflectance of that area.

During reproduction, the reproduction beam 33' irradiated from the recording and reproduction laser 3 passes through the same path as the recording light beam 33 and is irradiated onto the optical disk 1, and the change in reflectance depending on the presence or absence of a recording spot becomes the change in the reproduction light. The reflected light that has followed the opposite path to the irradiated light changes its direction by the beam splitter 6, and only the reflected light enters the photodetector 14 by the wavelength selection filter 13, and the change in reflectance on the optical disk 1 is converted into an electrical signal. The signal processing circuit 16. Demodulation circuit 19. Decoder 2
0, the reproduced data 31 is output.

On the other hand, during erasing, the recording and erasing gate generation circuit 16 sends an erasing gate signal 22 to the laser drive circuit 12.

The laser drive circuit 12 is a circuit that controls the erasing laser 11 having a wavelength λ2, and an erasing light beam 34 is irradiated during the period in which the erasing gate signal is "H". The irradiated erasing light passes through the condensing lens 10, changes its direction at the wavelength selection filter 6, and thereafter irradiates the optical disc 1 along the same path as the recording light, and is irradiated as a long elliptical spot on the guide track. Erasing is performed by restoring the reflectance. Note that in FIG. 1, the wavy line indicates the erasing optical path.

The rewritable optical recording and reproducing apparatus of this embodiment performs recording, reproduction, and erasing with the above configuration. Furthermore, the optical recording/reproducing apparatus of this embodiment has the following functions.

The optical recording/reproducing apparatus of this embodiment performs self-diagnosis when the power is turned on. That is, first, when the power is turned on, a specific track on the optical disc 1 is erased. Next, the test data generation circuit 26
generates random test data 26 and records it on the specific track. Next, the device reproduces the specific track, generates reproduction test data 27, and sends it to the comparator 24. The comparator 24 is connected to the test data 2.
5 and reproduction test data 27, and if they do not match, a mismatch signal 28 is output. The counter 23 is the mismatch signal 2
8, and when it reaches a certain number N or more, a bad system signal 29 is output.

The rewritable optical disk device of this embodiment configured as described above records and reproduces test data every time the power is turned on, and detects system abnormalities by itself by comparing the recorded data and the reproduced data. be able to. That is, when the bad system signal 29 is generated, it can be considered that there is an abnormality in one disk device, a decrease in the recording and erasing ability due to deterioration of the disk, or another abnormality in the disk. The counter set N is determined by taking into consideration the recording accuracy of the system, the performance and life of the disk, and
It can be determined appropriately.

A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 shows the configuration of a rewritable optical recording/reproducing device showing a second embodiment of the present invention.

In the figure, 1 to 31 are the same as 1 to 31 in FIG. 34 is an unerased detection circuit.

The optical disk device of this embodiment records, reproduces, and erases data using a configuration similar to that of the first embodiment.

Furthermore, the optical disk device of this embodiment has the above functions.

The optical disk device of this embodiment first generates random test data 26 by the test data generation circuit 26 each time the power is turned on. Next, the generated test data 26 is recorded on a specific track of the optical disc 1. Next, the specific track is erased and reproduced. Here, the signal processing circuit 16
A reproduction envelope signal 35 of the recorded data is sent from the recording data. Figure 3 is an example of an envelope signal, and in the figure,
a is the envelope signal when normal data is recorded, C is the envelope signal when it is unrecorded or completely erased, and e is the envelope signal when there is an omission of erasure. b, d.

f is a signal waveform when each of them is passed through a low-pass filter. The unerased detection circuit 34 receives the reproduced envelope signal 35 and outputs an unerased detection signal 36 if the unerased portion is greater than a certain level.

FIG. 4 shows an example of the configuration of the unerased detection circuit. 37 is mouth~
The pass filter 38 is a divider, 39 is a comparator, 4
o is a threshold. The threshold value 40 can be appropriately determined depending on the characteristics of the optical disc or the erasing ability of the recording/reproducing device.

The rewritable optical disk device of this embodiment configured as described above records, erases, and records test data every time the power is turned on.
By performing playback and looking at the playback envelope signal, it has become possible to detect unerased portions, that is, deterioration of the erase sensitivity of the optical disk, or abnormalities in the optical disk device itself.

The first point mentioned above. In the second example, the specific track may be any track on the optical disk, provided that it is a track that is not accessed during normal operation. Also number 1. In the second example, the diagnostic procedure is performed every time the power is turned on, but it may be performed at any timing, for example, once every fixed period of time.

It goes without saying that the present invention is not limited to the embodiments described above and illustrated, and that various modifications and applications can be made without departing from the gist of the invention.

Effects of the Invention The rewritable optical recording and reproducing device of the present invention can prevent the deterioration of the recording sensitivity of an optical disc by recording a test signal on a specific track and providing means for detecting whether the recording level is at a predetermined level. The rewritable optical recording and reproducing apparatus of the present invention also includes means for recording a test signal on a specific track, erasing it, and detecting whether the level of the erased signal is at a predetermined level or not. If provided, it is possible to detect the deterioration of the erasing sensitivity of the optical disc, and stable recording and reproduction of data can be performed, which has a great practical effect.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a rewritable optical recording and reproducing apparatus according to a first embodiment of the present invention, FIG. 2 is a block diagram of a rewritable optical recording and reproducing apparatus according to a second embodiment of the present invention, and FIG. The figure is an illustrative waveform diagram of the reproduced envelope signal, and FIG. 4 is a circuit diagram of one embodiment of the unerased detection circuit. DESCRIPTION OF SYMBOLS 1... Optical disc, 2... - Laser drive circuit, 3... Laser for recording and reproduction, 11...
・Erasing laser, 12... Laser drive circuit, 14
...Photodetector, 15...Signal processing circuit,
23...Counter, 24...Comparator, 25...Test data generation circuit, 34...
...Unerased detection circuit, 37...Ronogus filter, 38...Integrator, 39...-converter.

Claims (2)

[Claims] (1) A light source such as a laser beam is condensed into a minute spot light, and a signal is recorded and reproduced by applying a thermal change to the optical disk, and the recorded signal is erased by irradiation with output light from a laser, etc. a signal recording means for recording a test signal on a track; a signal erasing means for erasing the test signal recorded on the specific track; an erasing level detecting means for reproducing the specific track and detecting the level of the test signal remaining after erasing; A rewritable optical recording and reproducing device comprising a life notification stage that determines that the erasure life of the disc has reached and notifies the user when the level of the remaining erasure is equal to or higher than a predetermined level. (2) A light source such as a laser beam is condensed into a minute spot light, and a signal is recorded and reproduced by applying a thermal change to the optical disk, and the recorded signal is erased by irradiation with an output light such as a laser, and the specified a signal recording means for recording a test signal on a track; a recording level detection means for reproducing the test signal recorded on the specific track and detecting the recording level of the test signal; A rewritable optical recording/reproducing device comprising: a life notification means for determining and notifying when the recording life of a disk has reached; and a signal erasing means for erasing the test signal.