JP2636710B2 - Rewritable optical recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rewritable optical recording / reproducing apparatus for recording / reproducing information on / from an optical storage medium by using optical means.

[0002]

2. Description of the Related Art In a rewritable optical recording / reproducing apparatus such as a magneto-optical disk apparatus, a laser beam using a semiconductor laser diode or the like as a light source is used as information recording / reproducing means. And is irradiated onto the optical storage medium. At the time of recording information, a laser beam intensity-modulated according to the supplied recording data is irradiated onto the medium surface. On the other hand, an external magnetic field is supplied to the surface of the optical storage medium, and a magnetization reversal mark is formed on the surface of the optical storage medium due to the local temperature increase effect by the laser light, thereby storing information. Further, at the time of reproducing information, a laser beam having a constant intensity that does not disturb the stored information is irradiated onto the optical storage medium surface, and a change in the polarization plane of the reflected light corresponding to the magnetization reversal mark is detected as an electric signal, and the binary value is detected. After signal conversion,
Information reproduction is performed from reproduction timing discrimination using the reproduction clock signal as a discrimination reference.

In the above-described recording and reproduction processes, it is important to ensure a stable low error rate during information reproduction, in other words, how to secure a timing margin in discrimination of reproduction timing. For this reason, at the time of recording, optimization setting of recording circuit parameters such as recording power intensity and recording pulse width of laser light is required. During reproduction, optimization of reproduction circuit parameters such as a reproduction equalization constant for compensating for a decrease in reproduction resolution and a reproduction binarization threshold value is required.

Conventionally, recording circuit parameters and reproducing circuit parameters (hereinafter, referred to as "recording / reproducing circuit parameters") in this type of rewritable optical recording / reproducing apparatus are determined by fixing optimum values from experimental results relating to a reproduction timing margin. It was used regularly. Previously, it was relatively easy to secure a margin, so that variations in characteristics between devices or between media were acceptable within the margin. However, the above-mentioned reproduction timing margin has been declining with the recent increase in recording density and speed due to the demand for large capacity / high performance. As a countermeasure, some devices use a test area outside the user's area on the medium when loading the medium, etc., and execute a recording / reproduction test to determine whether the reproduction error rate is within the specified value. The self-optimization setting for confirming the normality of the recording / reproducing system and for adapting the recording / reproducing circuit parameters of the device to the actual medium has been started from the recording / reproducing test.

For example, Japanese Patent Laid-Open Publication No. Hei 3-116566 is directed to an overwritable magneto-optical recording medium, and the recording, erasing and reproducing laser beam intensity parameters are read from a recording / reproducing test. A method for optimizing under conditions that minimize errors has been proposed.

[0006] The test area is described in ISO / IE.
130m specified by C10089 (JIS X 6271)
As an example of an m-rewritable optical disk cartridge, as shown in FIG. 10, a manufacturer test area and a protection area are defined in the inner and outer peripheral areas outside the user use area from the format condition, and this area is defined as the test area. Can be used as

[0007]

As described above , the purpose of the recording / reproducing test in the conventional rewritable optical recording / reproducing apparatus is as follows. The first is to determine the normality of the recording / reproducing circuit function. Second, the recording / reproducing circuit parameter suitable for the medium to be used is corrected to an optimum value, thereby achieving safe operation of the apparatus with a low reproduction error rate. However, since information such as the previous reproduction error rate, the number of times of recording in the test area, and the last optimized recording / reproduction circuit parameter value is not managed, the following disadvantages are involved.

[0008] The reproduction error rate obtained in the recording / reproduction test is a result as an overall performance including the medium and the device. Therefore, it cannot be determined whether the reproduction error is caused by the medium or the device. Therefore, when a high reproduction error rate is detected by the recording / reproduction test, the cause is not specified even if the user can confirm the abnormal state.
For this reason, it is impossible to determine whether the medium needs to be replaced or the device needs to be repaired.

No management is performed on the life of the medium, such as the number of uses and the number of years of use. Therefore, it is not possible to exchange the medium before the medium whose life has expired breaks down.

[0010] A large number of recording / reproducing tests may deteriorate the characteristics of the medium in the test area more than the user area. In this case, in the medium having the deteriorated test area, the recording / reproducing circuit parameters are suitable for the test area but are not suitable for the user area which has not deteriorated. For this reason, there is a risk that erroneous parameter setting or the like in which the reproduction timing margin is excessively reduced is performed.

The recording / reproducing circuit parameter optimization setting processing is executed unconditionally so as to obtain the minimum error rate when the medium is loaded. Therefore, even when each parameter has already been matched, the optimization setting process is performed. The time required for this optimization setting process is unnecessary.

Conventionally, in the above-mentioned optimization setting processing of the recording / reproducing circuit parameters, an average fixed value based on an experimental result is uniformly given as an initial value of each parameter without considering the characteristic variation between media. Was. Therefore, the convergence of the parameter setting becomes slow due to the characteristic difference from the medium actually used, and the processing time required for the optimization setting becomes long. In addition, in this case, since a large number of recording / reproduction tests are required, there is a problem that the characteristic deterioration in the test area, which has been a problem, is further accelerated.

[0013]

The main objects of the present invention are as follows.

A) It is clarified whether the cause of the high reproduction error rate is in the medium or the device.

B) To suppress the influence of the deterioration of the test area.

(C) Eliminating useless optimization setting processing of the recording / reproducing circuit parameters.

[0017]

A rewritable optical recording / reproducing apparatus according to the present invention comprises recording means for writing information on an optical recording medium according to recording circuit parameters, and reproducing means for reading information from the optical recording medium according to reproduction circuit parameters. And a rewritable optical recording / reproducing apparatus which obtains a reproduction error rate by performing a recording / reproducing test on a test area of the optical recording medium by the recording means and the reproducing means.

The main points of the improvement are as follows.

(1) A reproduction error rate management means for writing the reproduction error rate in the test area by the recording means and reading the reproduction error rate written in the test area by the reproduction means, before and after the recording / reproduction test Recording / reproduction control means for reporting an abnormality or changing the recording circuit parameters and the reproduction circuit parameters based on the difference in the reproduction error rate. In this case, the recording / reproducing control means may report an abnormality of the optical recording medium when both the error rates before and after the recording / reproducing test are equal to or more than a predetermined value. Further, the recording / reproducing control means, when the amount of increase in the reproducing error rate after the recording / reproducing test with respect to the reproducing error rate before the recording / reproducing test is a predetermined value or more, the rewritable optical recording / reproducing apparatus An abnormality may be reported. Further, the recording / reproducing control means is configured to minimize the reproducing error rate when an increase in the reproducing error rate after the recording / reproducing test with respect to the reproducing error rate before the recording / reproducing test is equal to or more than a predetermined value. The correction of the recording circuit parameter or the reproduction circuit parameter may be performed as described above.

(2) Recording / reproduction parameter management wherein the recording circuit parameters and the reproduction circuit parameters are written in the test area by the recording means, and the recording circuit parameters and the reproduction circuit parameters written in the test area are read by the reproduction means. Means and a recording / reproduction control means for reporting an abnormality or changing the recording circuit parameters and the reproduction circuit parameters based on a difference between the recording circuit parameters and the reproduction circuit parameters before and after the recording / reproduction test. In this case, the recording / reproduction control means may report an abnormality when a difference between the recording circuit parameter and the reproduction circuit parameter before and after the recording / reproduction test is equal to or more than a predetermined value. Further, the recording / reproduction control means, when the reproduction error rate of the recording / reproduction test is within a predetermined value, retains the recording circuit parameters and the reproduction circuit parameters before the recording / reproduction test as they are, after the recording / reproduction test. May be used as the recording circuit parameter and the reproduction circuit parameter.

(3) In addition to the above (1) or (2),
Te, and attaching a recording test count management means for reading the accumulated values written in the test area and writes to the test area by said recording means the accumulated value of the number of times that the recording test by the reproducing means, A device for changing the test area when the cumulative value is equal to or more than a predetermined value.
A function is added to the recording / reproduction control means.

[0022]

The recording / reproduction control means inputs the reproduction error rates before and after the recording / reproduction test via the reproduction error rate management means.
Based on these changes in the reproduction error rate, an abnormality is reported or the recording / reproducing circuit parameters are changed.

The recording / reproduction control means inputs recording / reproduction circuit parameters before and after the recording / reproduction test via the recording / reproduction parameter management means. Based on these changes in the recording / reproducing circuit parameters, an abnormality is reported or the recording / reproducing circuit parameters are changed.

The recording / reproducing control means inputs a cumulative value of the number of times of performing the recording / reproducing test via the recording / reproducing test number managing means. If the accumulated value is equal to or more than the predetermined value, the test area is changed.

[0025]

FIG. 1 is a block diagram showing an embodiment of the present invention. Hereinafter, description will be made with reference to this drawing.

The optical head 3 has a laser diode 3 inside.
A and the photodetector 3B. A magnetization reversal mark 4A is formed on the medium 4. The medium 4 is rotated by a spindle motor 5.

The recording means comprises a recording pulse correction circuit 1, a current driving circuit 2, a laser diode 3A and the like. The reproducing means includes an optical detector 3B, an amplifier circuit 6,
It comprises a reproduction equalization circuit 7, a reproduction pulse generation circuit 8, a reproduction data discrimination circuit 9, and the like. The reproduction error rate management means includes a reproduction error rate detection circuit 10 and the like. The recording / reproduction control means includes a parameter optimization control circuit 11, a memory circuit 13, and the like.

First, a normal recording / reproducing operation will be described. At the time of writing information, a write data signal is supplied to the recording pulse correction circuit 1, where the magnetization reversal mark is stabilized on the medium 4 based on the medium recording sensitivity characteristics or the linear velocity condition of the track position (media radius position) to be recorded. 4
The recording timing is corrected so as to form A. After that, the current is converted into a recording current corresponding to the light intensity at the time of recording which is also optimized from the medium recording sensitivity and the linear velocity condition in the current driving circuit 2, and the laser diode 3A in the optical head 3 is current-driven. The laser diode 3A emits an optical output having an intensity proportional to the supplied current, and the optical output is condensed by an optical lens provided in the optical head 3 and radiated onto the medium 4 which is rotationally driven by a spindle motor 5. Is done.
On the other hand, although not shown in FIG. 1, an external magnetic field having different polarities is supplied to the medium surface for erasing and recording, and the local temperature rise on the medium 4 due to the irradiation of the light output described above. The recording of the information is completed when the magnetization reversal mark 4A is formed on the medium.

In reproducing information, first, a current corresponding to a constant intensity light output that does not disturb the information on the medium is supplied to the laser diode 3A by the current driving circuit 2, and the light output is applied to the medium surface. A change in the polarization plane corresponding to the magnetization reversal mark 4A is detected from the reflected light using the Kerr effect, and is converted into an electric signal by the photodetector 3B. The reproduced analog signal output from the optical detector 3B is amplified by the amplifier circuit 6, and the reproduction equalization circuit 7 enhances the harmonic components of the signal to compensate and equalize the signal distortion caused by the waveform interference. It is supplied to the pulsing circuit 8. In the reproduction pulsing circuit 8, the level of the supplied reproduction analog signal after reproduction equalization is compared with a threshold value, and is converted into a reproduction data pulse which is a binary digital signal. The reproduced data pulse is supplied to the next reproduced data discriminating circuit 9, and information is reproduced by obtaining a read data signal from a reproduction timing discrimination based on a reproduction clock signal phase-synchronized with the reproduced data pulse as a discrimination reference.

Next, the operation during the recording / reproducing test will be described. First, when a test start signal is supplied to the main control circuit 12 from start-up conditions such as device power-on, medium loading, or detection of a temperature change equal to or more than a predetermined value, the light beam position in the optical head 3 is set to the test area. The reproduction error rate information in the test management area provided in the test area is reproduced in the same procedure as the normal information reproduction described above, and stored in the memory circuit 13. The stored reproduction error rate (ES) corresponds to the pre-test reproduction error rate immediately before the recording and reproduction test on the same medium.

Thereafter, the main control circuit 12 issues a test command to the error rate detection circuit 10, and the error rate detection circuit 10 supplies test data to the recording pulse correction circuit 1,
The test recording in the test area in the test area and the data reproduction in the same area are executed in the same procedure as the normal recording / reproducing operation described above. Further, the error rate detection circuit 10 calculates a reproduction error rate from a comparison between the test data and the reproduction data of the same data, and reports the reproduction error rate (ET), which is a test result, to the main control circuit 12.

In the main control circuit 12, the reproduction error rate (E
In response to the report of T), the following state determination is performed by comparison with the previous storage error rate (ES).

When ET ≦ predetermined prescribed value: It is determined that both the device and the medium are normal.

When ET ≧ predetermined prescribed value and ES ≧ predetermined prescribed value: The result of the previous recording / reproducing test for the medium or the test result after the optimization setting of the recording / reproducing circuit parameters, and the current recording In both of the reproduction test results, the reproduction error rate cannot satisfy the specified values, and the medium is determined to be abnormal based on the characteristic deterioration due to the life of the medium and the like.

Therefore, when this state is determined, a medium abnormality warning signal is output to warn the user from means such as lamp display or message display.

ET ≧ predetermined prescribed value, but ES ≦ predetermined prescribed value: The result of the previous recording / reproducing test on the medium or the test result after the optimization setting of the recording / reproducing circuit parameters was normal. However, according to the result of the current recording / reproducing test, the reproducing error rate cannot satisfy the specified value, and it is determined that there is some abnormality relating to the recording / reproducing function of the apparatus or that the recording / reproducing circuit parameters are incompatible.

Therefore, when this state is determined, a device abnormality warning signal can be output to warn the user from means such as lamp display or message display. In addition, it is also possible to activate the recording / reproducing circuit parameter optimization setting processing described below to return the apparatus state to a normal state.

The optimization setting of the recording / reproducing circuit parameters is as follows:
While activating the parameter optimization control circuit 11 from the main control circuit 12, a test command is issued to the reproduction error rate detection circuit 10 in the same manner as in the above-described recording / reproduction test, and the recording / reproduction circuit parameters are modified and changed in the test area. A process for detecting and setting the optimal parameter under the condition that the reproduction error rate (ET) is equal to or less than a predetermined value or the minimum is performed by repeating the recording / reproduction test in the test area. The target parameters of the recording / reproducing circuit in the parameter optimization control circuit 11 include a recording timing correction time of the recording pulse correction circuit 1, a laser diode driving current corresponding to the recording light output intensity of the current driving circuit 2, a reproduction equalizing circuit 7 , The pulsating threshold in the reproduction pulsing circuit 8, and the like.

As an optimization method, a method of sequentially setting all circuit parameters one by one, a method of setting optimization by combining a plurality of circuit parameters,
Alternatively, there is a method of giving optimization priorities to circuit parameters, sequentially performing optimization settings, and stopping the process when a predetermined reproduction error rate is obtained. However, the method is not particularly limited. However, as a procedure, from the test recording under the standard recording parameter conditions, the reproduction parameter optimization of the reproduction equalization circuit 7 and the reproduction pulse generation circuit 8 precedes the recording parameter correction of the recording pulse correction circuit 1 and the current drive circuit 2. It is desired to execute the processing in order to prevent the recording parameters from being erroneously set due to erroneous reproduction parameter conditions.

Thereafter, as the last processing, the main control circuit 12 sets the reproduction error rate test result in the above-described recording / reproduction test or the final reproduction error rate after the recording / reproduction circuit parameter optimization setting processing as error rate information, and A recording process is executed to update the test management area in the test area, and a series of processes ends. The recording process in this case is performed by the main control circuit 12.
Supplies the above error rate information to the recording pulse correction circuit 1 and is executed in the same procedure as a normal information recording operation.

Next, the recording / reproducing circuit parameter control targeted in the above-mentioned optimization setting will be described in detail. First, FIG. 2 shows an example of the circuit configuration of the recording pulse correction circuit 1.
FIG. 3 is an operation waveform diagram relating to FIG. The write data signal a is supplied to the first delay circuit 1A and the second delay circuit 1B, and a first delay signal b and a second delay signal c having delay times T1 and T2 are generated, respectively. Thereafter, the first delay signal b is supplied to the set input of the flip-flop circuit 1C, and the second delay signal c is supplied to the reset input of the flip-flop circuit 1C after the polarity is inverted by the inverter circuit 1D. Generates a recording pulse d. That is, the recording pulse d is a signal delayed by the time T1 at the leading edge and delayed by the time T2 with respect to the write data signal a, but the time T2 is variably controlled by the delay control data. As a result, the pulse width corresponding to the section of "1" is determined by the delay control data. In the optimization setting of the parameters, when the recording sensitivity is reduced, the interval between the magnetization reversal marks is formed to be narrower than the recording pulse interval, so that the T2 time is increased when the recording sensitivity is high. If the control is performed so that T2 becomes small, the variation in the recording sensitivity can be corrected.

Next, FIG. 4 shows an example of a circuit configuration of a recording current supply section of the current drive circuit 2. The above-mentioned recording pulse is supplied to a current switch circuit 2A, while a current supply circuit is supplied to the current switch circuit 2A. Power control data and D from 2B
Since the current determined by the -A conversion circuit 2C is supplied, only the "1" section of the recording pulse d in FIG. 3 is output as a recording current to drive the laser diode 3A for recording and emission. Since the laser beam intensity during recording and the recording current are in a proportional relationship, and the recording current value is determined from the power control data, the variation in the recording sensitivity is also corrected by the power control data as in the previous recording pulse width correction. Will be able to do that.

Therefore, in order to correct the recording sensitivity variation caused by the environmental conditions such as the medium characteristics or the temperature and to obtain the optimum recording condition, either the correction of the recording pulse width or the correction of the recording current value as described above. Alternatively, by executing both, the optimum condition can be set. In particular, when the recording light output approaches the maximum output power rating of the laser diode and there is no room for correction, it can be said that the recording pulse width correction is advantageous, and as shown in FIG. When the waveform has a complicated pulse waveform shape such as a multi-pulse shape, the recording current value correction is more advantageous from the viewpoint of easy control.

FIG. 6 shows an example of a circuit configuration of the reproduction equalization circuit 7, which is called a cosine equalization circuit. The reproduced signal is supplied to a delay line 7A with an intermediate tap and a gain control addition circuit 7B. The output of the last stage of the delay line 7A is supplied to the other addition input of the gain control addition circuit 7B, and the output of the intermediate tap is supplied to a difference detection circuit 7C. You.
Further, the output of the gain control addition circuit 7B is the difference detection circuit 7C.
, Which is configured to detect a difference from the intermediate tap output. When the total delay time of the delay line 7A is 2τ, the gain of the gain control addition circuit 7B is K, the gain of the difference detection circuit 7C is 1, and the frequency is represented by f,
The frequency characteristic of the reproduced equalized signal with respect to the reproduced signal is 1-K
Cos (2π · τ · f)

In the frequency characteristic, the higher the K, the higher the frequency component is emphasized relatively. By changing the gain of the gain control addition circuit 7B according to the equalization gain control data, the higher harmonics of the reproduced signal are obtained. The relative gain with respect to the wave component can be controlled.

The reproduction equalization has the purpose of compensating for the deterioration of the characteristics of the reproduction system by relatively emphasizing the harmonic signal components and reducing the reproduction signal interference. Because of the deterioration of the / N ratio, there is naturally an optimization condition from both conditions, that is, equalization gain control data corresponding to the harmonic emphasis gain.

FIG. 7 shows an example of a circuit configuration of the reproduction pulse conversion circuit 8. The reproduction pulse generation circuit 8 receives a reproduction equalization signal output from the reproduction equalization circuit 7 and sends the signal to the envelope detection circuit 8A and the level comparison circuit 8B. The same signal is supplied. The envelope detection circuit 8A detects the median of the positive and negative envelope levels of the reproduced equalized signal, and performs the level correction on the median level by the addition circuit 8C, and then supplies it to the level comparison circuit 8B as a pulse threshold. You. As a result, as shown in FIG. 8, the level comparison circuit 8B compares the level of the reproduced equalized signal with the pulsing threshold, and converts the signal into a reproduced pulse which is a binary signal. Since a signal obtained by converting the pulsed threshold control data into an analog level by the DA converter 8D is supplied to the adder circuit 8C,
This signal enables pulsing in a state where the pulsing threshold is shifted from the center value of the envelope of the reproduced equalized signal. By the way, in FIG. 8, when the pulse threshold is shifted from the median to the positive side as shown by the broken line, the pulse is reproduced in a situation where the pulse width of the reproduction pulse is small. That is, it is sufficient to set the pulse threshold control data so as to minimize the pulse position shift caused by the circuit offset of the level comparison circuit 8B or the like.

In the above-mentioned recording / reproducing test, especially in the process of optimizing the parameters of the recording / reproducing circuit, the reproduction error rate is used as a criterion for the pass / fail judgment or the optimization judgment.
The reproduction error rate is governed by a fixed error rate due to a medium defect or the like, and it may be difficult to detect a clear error rate change or a minimum error rate state in response to a change in each recording / reproducing circuit parameter. In this case, if necessary, a method of setting the discrimination window time width in the reproduction data discrimination circuit 9 narrower than that of the normal reproduction or a method of shifting the pulsation threshold value in the reproduction pulsation circuit 8 from the optimum state as described above. By using such a condition, a condition in which the reproduction timing margin is further reduced is set, and a clear error rate determination can be performed. FIG. 9 conceptually shows a reproduction discrimination window in the reproduction data discrimination circuit 9, and is shifted from an original position by setting a test window time TM smaller than the normal window time TN. This means that a discrimination error is generated with respect to the discrimination data pulse as indicated by the broken line, that is, a situation is set which is more easily detected as a reproduction error.

In the above embodiment, the mark edge recording using the edge position of the magnetization reversal mark as the information point has been described as a recording method on the medium. However, the present invention is not particularly limited. Also in the mark position recording using the center position of the magnetization reversal mark as the information point, although the detailed configuration of the specific circuit is different, the same effect can be obtained with the same circuit configuration requirements.

Next, another embodiment of the present invention will be described with reference to the drawings. FIG. 11 is a block diagram showing another embodiment of the present invention. However, the same parts as those in FIG.

The recording means comprises a recording pulse correction circuit 1, a current driving circuit 2, a laser diode 3A and the like. The reproducing means includes an optical detector 3B, an amplifier circuit 6,
It comprises a reproduction equalization circuit 7, a reproduction pulse generation circuit 8, a reproduction data discrimination circuit 9, and the like. The reproduction error rate management means includes a reproduction error rate detection circuit 10 and the like. The recording / reproducing parameter managing means, the recording / reproducing test number managing means, the recording / reproducing control means, and the like are constituted by a parameter optimization control circuit 11, a main control circuit 12, a memory circuit 13, a track control circuit 14, and the like.

In this apparatus, the discrimination margin in the data discrimination circuit 9 decreases with the increase in recording density and the speed of recording / reproducing processing. Therefore, a recording / reproducing test is performed in a test area outside the user data recording area. Then, a parameter optimizing process for adapting the recording / reproducing circuit parameters to the actually used medium is performed. In this case, first turn on the device power,
Alternatively, when a test start signal is supplied to the main control circuit 12 under the condition of detecting a temperature change equal to or greater than a predetermined value, the track control circuit 14 is driven to change the light beam position of the optical head 3 to the test management area of the test area. Set to. Thereafter, the management information in the same test management area is reproduced and stored in the memory circuit 13 in the same procedure as the normal information reproduction described above.
The storage management information includes, as pre-test management information, at least the cumulative test recording count of the test area and the optimization setting value of the recording / reproducing circuit parameter immediately before the parameter optimization processing performed on the same medium. include.

Next, the main control circuit 12
The pre-test management information stored in 3 is supplied to the parameter optimization control circuit 11 as initial values of the recording / reproducing circuit parameters, and a test command is output to the reproducing error rate detecting circuit 10. The reproduction error rate detection circuit 10 receives the test command, supplies test data to the recording pulse correction circuit 1, performs test recording in a test area in the test area in the same procedure as the normal recording / reproduction operation described above, and performs test recording in the test area. Execute data playback. Further, the reproduction error rate detection circuit 10 calculates the reproduction error rate from the comparison between the test data and the reproduction data of the same data, and reports the reproduction error rate information as the test result to the main control circuit 12.

The main control circuit 12 receives the report of the reproduction error rate information, and when the reproduction error rate is equal to or more than a specified value,
Alternatively, it instructs the parameter optimization control circuit 11 to change the recording / reproducing circuit parameters unconditionally, and adds 1 to the cumulative test recording number stored in the memory circuit 13. Thereafter, when the accumulated number of recordings after the addition processing is equal to or less than a specified value, the test area is the same, and when the accumulated number of times is equal to or more than the specified value, the track control circuit 14 is driven to change the test area. Is cleared to 0, and a test command for performing the same recording and reproduction test as described above is output to the reproduction error rate detection circuit 10.

The main control circuit 12 repeatedly executes the above-mentioned recording / reproducing test processing while instructing the parameter optimization control circuit 11 to change the recording / reproducing circuit parameters, and reproduces the reproduction error rate reported from the reproduction error rate detection circuit 10. The information is monitored and the optimum recording / reproducing circuit parameters are detected and set according to the determination conditions for obtaining the minimum reproduction error rate. In addition,
Naturally, 1 is added to the cumulative recording count every time test recording is performed.

The recording / reproducing circuit parameters to be optimized in the parameter optimization control circuit 11 include a recording timing correction time of the recording pulse correction circuit 1 and a laser diode driving current corresponding to the recording light output intensity of the current driving circuit 2. , A harmonic emphasis gain amount in the reproduction equalization circuit 7, a pulsing threshold value in the reproduction pulsation circuit 8, and the like. As an optimization method, a method of sequentially optimizing and setting all circuit parameters one by one, a method of optimizing and setting a plurality of circuit parameters in combination, or a method of sequentially optimizing circuit parameters with an optimization priority There is a method of optimizing the setting and stopping the process when a predetermined reproduction error rate is obtained, but the method is not particularly limited. However, as a procedure, the optimization of the reproduction parameters of the reproduction equalization circuit 7 and the reproduction pulse generation circuit 8 from the test recording under the recording parameter conditions of the initial values to the optimization of the recording parameters of the recording pulse correction circuit 1 and the current drive circuit 2 It is desired to execute the process in advance in order to prevent erroneous setting of the recording parameter from an erroneous reproduction parameter condition.

In the above-described recording / reproducing circuit parameter optimizing process, the initial value parameter supplied to the parameter optimizing control circuit 11 is the parameter value in the parameter optimizing process executed immediately before for the medium. Therefore, it can be said that there is a high possibility that the values match the optimum values in the parameter optimization processing unless there is a large change in environmental conditions such as temperature. For this reason, in the recording / reproducing test using the initial value parameters, the main control circuit 12 sets an allowable value for the reproducing error rate, and only when the reproducing error rate reported from the reproducing error rate detecting circuit 10 is equal to or more than the allowable value, Is performed, and when the value is equal to or smaller than the allowable value, the initial value parameter can be regarded as the optimization parameter and the process can be terminated. This method is more effective in reducing unnecessary recording times and processing time in the test area.

Further, the parameter optimization setting circuit 11 compares each parameter value of the recording / reproducing circuit which has been optimized and the initial value parameter value, and detects a difference between them both equal to or larger than a predetermined value. In such a case, if it is determined that there is an abnormality in the operation of the device, a warning signal of a parameter abnormality is output and a warning can be given to the user by means such as lamp display or message display.

After the above optimization setting of the recording / reproducing circuit parameters, as a final process, the main control circuit 12 updates the test management area of the test area using the set circuit parameters and the cumulative recording count for the test area as management information. The recording process is executed, and a series of processes ends. In this case, the recording process is performed by supplying the management information from the main control circuit 12 to the recording pulse correction circuit 1 and performing the same procedure as the normal information recording operation.

In the embodiment shown in FIG. 11, the reproduction error rate is used as the optimum determination condition when optimizing the recording / reproducing circuit parameters. However, the present invention is not particularly limited to this. May be the condition for obtaining the reproduction timing margin, that is, the best condition for the reproduction signal. As the best condition of the reproduction signal, a condition for obtaining a maximum reproduction analog signal amplitude, a reproduction resolution defined by a reproduction analog amplitude ratio at a maximum recording density and a minimum recording density that can occur on a data pattern become a specified value, or It is possible to use a condition that is within a specified range, or a condition that the duty ratio of a reproduction pulse when recorded under a single recording density condition is a specified value, or that is within a specified range.

The details of the test area are not particularly limited, and the recording / reproducing test is performed in units of one track corresponding to one round of the medium or one sector obtained by disassembling the track. It is stored and managed as management information together with the accumulated test record in the test management area of the test area. When the cumulative number of test recordings is equal to or more than the specified value, the test area is replaced. In this case, the update of the test area address is also performed based on the management information.

In the above embodiment, the mark edge recording using the edge position of the magnetization reversal mark as the information point has been described as a recording method on the medium. However, the recording method is not particularly limited. In the mark position recording using the center position of the inverted mark as the information point, the detailed effect of the specific circuit is different, but the same effect can be obtained with the same circuit configuration requirements.

[0063]

According to the present invention, by storing and managing the reproduction error rate information in the test area at the time of the recording / reproduction test or after setting the recording / reproduction circuit parameter optimization, the cause of the abnormality relating to the increase of the reproduction error rate is obtained. It is possible to determine whether the device is in the device or the medium. Further, by activating the recording / reproducing circuit parameter optimizing process according to the discrimination result, unnecessary recording times for the medium test area are reduced, and erroneous recording / reproducing due to poor medium characteristics due to multiple recordings in the test area. There is an effect that setting of circuit parameters is avoided. As a result, the normality relating to the reproduction error rate in the actually used medium is set, and the optimum circuit parameters suitable for the medium characteristics are set, so that a low reproduction error rate can always be achieved by ensuring a stable reproduction timing margin.

According to the present invention, in addition to the above effects,
Stores and manages the cumulative number of test recordings in the test area and the optimized recording / reproducing circuit parameters of the immediately preceding execution in the test area, and replaces or stores the test area according to the cumulative number of times of test recording during the optimization of the recording / reproducing circuit parameters. By using the circuit parameter as the initial value parameter for optimization, it is possible to avoid setting an erroneous recording / reproducing circuit parameter due to deterioration of medium characteristics due to an increase in the number of times of test recording. Further, since the recording / reproducing circuit parameter optimizing process is started from the parameter value optimized immediately before for the medium, the number of times of test recording in the test area and the processing time can be reduced. As a result, the optimum recording / reproducing circuit parameters suitable for the characteristics of the actual medium to be used are set stably, and a device state with a low reproduction error rate that always secures a reproduction timing margin is achieved.

[Brief description of the drawings]

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

FIG. 2 is a block diagram showing a recording pulse correction circuit according to one embodiment of the present invention.

FIG. 3 is an operation waveform diagram according to FIG. 2;

FIG. 4 is a block diagram showing a recording current supply unit of the current supply circuit according to one embodiment of the present invention.

FIG. 5 is a waveform diagram of a recording pulse in one embodiment of the present invention.

FIG. 6 is a block diagram showing a reproduction equalization circuit according to one embodiment of the present invention.

FIG. 7 is a block diagram showing a reproduction pulsing circuit according to one embodiment of the present invention.

FIG. 8 is a waveform chart showing the operation of reproducing pulses in one embodiment of the present invention.

FIG. 9 is a waveform diagram showing the concept of a regeneration discrimination window in one embodiment of the present invention.

FIG. 10 is an explanatory diagram showing a format configuration example of a medium relating to a test area.

FIG. 11 is a block diagram showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording pulse correction circuit 2 Current drive circuit 3 Optical head 4 Medium 5 Spindle motor 6 Amplification circuit 7 Reproduction equalization circuit 8 Reproduction pulsation circuit 9 Reproduction data discrimination circuit 10 Reproduction error rate detection circuit 11 Parameter optimization control circuit 12 Main control Circuit 13 Memory circuit 14 Track control circuit 3A Laser diode 3B Photodetector 4A Magnetization reversal mark

Claims (8)

(57) [Claims] A recording means for writing information to an optical recording medium in accordance with a recording circuit parameter; and a reproducing means for reading information from the optical recording medium in accordance with a reproducing circuit parameter. A rewritable optical recording / reproducing apparatus which obtains a reproduction error rate by performing a recording / reproduction test by a recording means and a reproduction means, wherein the reproduction error rate is written in the test area by the recording means, and the reproduction error written in the test area. A reproduction error rate management means for reading a rate by the reproduction means, and a recording / reproduction control means for reporting an abnormality or changing the recording circuit parameters and the reproduction circuit parameters based on a difference between the reproduction error rates before and after the recording / reproduction test. A rewritable optical recording / reproducing device, comprising: 2. The recording / reproduction control means according to claim 1, wherein said error rates before and after said recording / reproduction test are both equal to or greater than a predetermined value.
2. The rewritable optical recording / reproducing apparatus according to claim 1, wherein an abnormality of the optical recording medium is reported. 3. The rewritable optical recording device according to claim 2, wherein the recording / reproducing control means is configured to determine whether the reproduction error rate after the recording / reproducing test increases by more than a predetermined value with respect to the reproducing error rate before the recording / reproducing test. 2. The rewritable optical recording / reproducing apparatus according to claim 1, wherein an abnormality of the reproducing apparatus is reported. 4. The recording / reproducing control means, when the amount of increase in the reproducing error rate after the recording / reproducing test with respect to the reproducing error rate before the recording / reproducing test is a predetermined value or more, 2. The rewritable optical recording / reproducing apparatus according to claim 1, wherein the recording circuit parameter or the reproducing circuit parameter is corrected to be a minimum. 5. An optical recording medium comprising: recording means for writing information on an optical recording medium according to recording circuit parameters; and reproducing means for reading information from the optical recording medium according to reproduction circuit parameters. In a rewritable optical recording / reproducing apparatus that obtains a reproduction error rate by performing a recording / reproducing test by a recording unit and a reproducing unit, the recording circuit parameter and the reproduction circuit parameter are written in the test area by the recording unit and written in the test area. Recording / reproduction parameter management means for reading the recorded recording / reproduction circuit parameters by the reproduction means, and reporting an abnormality or the recording / reproduction circuit parameters based on a difference between the recording / reproduction circuit parameters before and after the recording / reproduction test. Of playback circuit parameters Further performed reproduction control means and the rewritable optical recording reproducing apparatus, comprising the. 6. The apparatus according to claim 5, wherein the recording / reproducing control unit reports an abnormality when a difference between the recording circuit parameter and the reproducing circuit parameter before and after the recording / reproducing test is equal to or larger than a predetermined value. A rewritable optical recording / reproducing apparatus according to the above. 7. The recording / reproducing control means, when a reproduction error rate of the recording / reproduction test is within a predetermined value, the recording / reproduction circuit parameter and the reproduction circuit parameter before the recording / reproduction test are left unchanged. 6. The rewritable optical recording / reproducing apparatus according to claim 5, wherein the recording circuit parameters and the reproducing circuit parameters after the test are used. 8. A rewritable optical recording / reproducing apparatus according to claim 1, wherein
In the raw apparatus, a recording / reproducing test frequency managing means is provided , wherein the cumulative value of the number of times of performing the recording / reproducing test is written to the test area by the recording means, and the cumulative value written to the test area is read by the reproducing means. is, the recording and reproduction control means, rewritable optical recording reproducing apparatus in which the accumulated value is equal to or make changes of the test area is equal to or greater than a predetermined value.