JPH08129754A - Method and device for recording/reproducing information - Google Patents

Abstract

PURPOSE: To improve reliability of information and recording capacity by precisely controlling length and width of a recording mark to be recorded on a recording medium. CONSTITUTION: A recording pulse line is generated by a test write pattern generation circuit 15 and a recording pulse generation circuit 11, and the recording mark is recorded on the recording medium 6 by a laser driver 10. Test write patterns constituted of two kinds are detected from a regenerative signal from the recording medium 6 by a test write pattern center level detection circuit 23, and recording power when the difference (recording condition deviation signal) becomes zero is made the optimum recording power. Further, after a servo state is changed, and the test write detecting the servo state in which the optimum recording power becomes minimum as the optimum servo state is performed, by performing regular recording/reproducing operation, recording mark fluctuation due to recording sensitivity fluctuation, etc., is suppressed. Further, the test write obtaining only the optimum recording power while fixing to the optimum servo state is executed combining with the former test write.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording / reproducing technique for recording / reproducing on / from a recording medium, and is particularly effective when applied to high-precision recording / reproducing control of recording marks by thermal recording in an optical disk device or the like. Regarding technology.

[0002]

2. Description of the Related Art In the technique of condensing laser light on an optical disk and recording information at high density by thermal recording,
Relative recording even when the recording sensitivity varies from optical disk to optical disk, the recording sensitivity of the optical disk changes due to changes in environmental temperature, and the focus position of the laser light deviates from the optical disk due to changes in the servo status. There is a problem that the sensitivity changes, and in order to improve the recording density of an optical disc, it is necessary to have a technique for forming the recording mark with high accuracy by suppressing the fluctuation of the recording mark even when the recording sensitivity changes as described above. there were. In this regard, conventionally, for example, in Japanese Unexamined Patent Publication No. 6-36285, recording is performed while changing the recording power, and defocus or disc tilt is given at the time of reproduction to obtain the recording power when the compare error is the minimum as the optimum power. One method of trial writing is shown.

[0003]

However, in the technique of the above-mentioned publication, since the correction means for the fluctuation of the recording sensitivity is only the recording power, the fluctuation of the recording sensitivity of each optical disk or the recording sensitivity of the optical disk due to the change of the environmental temperature is suppressed. In addition to the change, the recording power corrects even the relative change in recording sensitivity due to the focus position of the laser beam deviating from the optical disk due to the change in the servo state, and the optimum power range for these changes is There has been a problem that the correction becomes wider and the correction may not be possible due to the limit of the output of the laser light. Further, in the technique of the above publication, when the focus position of the laser beam deviates from the optical disk due to the change of the servo state, the optimum value of the defocus or the disk tilt given at the time of reproduction changes, so that the optimum power cannot be accurately obtained. There was a problem that there were cases.

The object of the present invention is to shift the focus position of light from the recording medium due to the fluctuation of the recording sensitivity of each recording medium, the change of the recording sensitivity of the recording medium due to the change of the environmental temperature, and the change of the servo state. Even if a relative change in recording sensitivity occurs due to the above, it is to improve the recording density of the recording medium by suppressing the fluctuation of the recording mark and forming the recording mark with high accuracy.

Another object of the present invention is information recording capable of shortening the time required for the trial writing operation for improving the compatibility between the recording medium and the recording / reproducing apparatus without degrading the reliability. It is to provide the reproduction technology.

[0006]

According to the information recording / reproducing technique of the present invention, the servo state is changed at a predetermined position of a recording medium, and the data of a predetermined pattern is recorded / reproduced while changing the recording power in each servo state. Then find the optimum recording power. By comparing the optimum recording powers obtained in each servo state, the servo state when the optimum recording power is the smallest is set as the optimum servo state, and the trial writing operation is performed in which the optimum recording power at that time is obtained as the final optimum recording power. After that, regular recording is started on the recording medium.

As the servo state, a focus servo state for controlling the focal position of the light irradiated on the recording medium, or a tracking for controlling the light irradiation position in the width direction of the track which is the recording area of the information recording medium. It can be applied to servo status. Further, it can be applied to an optical disc device using an optical disc as a recording medium.

[0008]

The relative change in recording sensitivity due to the focus position of the laser beam deviating from the recording medium such as the optical disk due to the change in the servo state is corrected by obtaining the optimum servo state and optimizing the servo state. Therefore, the correction by the recording power is performed by the variation of the recording sensitivity for each recording medium,
Only the recording sensitivity of the recording medium changes due to the change of the environmental temperature, the range of the optimum power does not widen, and there is no case where the correction cannot be performed due to the limit of the output of the laser light. Also,
Since the focus position of the laser beam is always on the recording medium and the recording power is always the optimum value, it is possible to suppress the fluctuation of the recording mark and form the recording mark with high accuracy, and improve the recording density of the recording medium. be able to.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an example of the configuration of an information recording / reproducing apparatus in which an information recording / reproducing method according to an embodiment of the present invention is implemented. The information recording / reproducing apparatus of this embodiment is obtained from an optical head centering on a laser 1, a recording medium 6 for storing information, a recording processing system centering on a recording pulse generation circuit 11, and an optical head. A reproduction processing system centering on a reproduction circuit 20 for converting the reproduced signal into information,
Etc. The recording medium 6 is composed of a recording film and a substrate holding the recording film.

The controller 16 decodes the command and information data from the upper host and decodes the command and converts the recorded data into a code string corresponding to the modulation method. The synthesizer 14 is an oscillator that generates a reference clock for the entire apparatus, and as a method of increasing the capacity, the ZC is used to change the reference clock for each zone to keep the recording density at the inner and outer circumferences substantially constant.
AV (Zoned Constant Angular)
When a recording method called “Velocity” is adopted, it is necessary to change the oscillation frequency of the synthesizer 14 according to the zone.

In order to improve compatibility between the recording medium 6 and a recording device, the trial writing is performed in advance on the recording medium 6 in advance.
At a predetermined position of, a test writing for detecting a change in film thickness of the recording medium 6 due to the replacement of the recording medium 6 and a change in recording sensitivity with respect to the recording medium 6 due to a change in environmental temperature and a change in characteristics of a recording apparatus. The pattern is written on the recording medium 6 before recording the regular information. This trial writing pattern is converted into a code string corresponding to the modulation method, and is generated in the trial writing pattern generation circuit 15. The code string modulated according to the regular information data from the controller 16 and the code string from the trial writing pattern generation circuit 15 are input to the selector 12, and the controller 1
The control signal 6 causes switching according to the trial writing process or the normal recording process. The code train from the selector 12 enters the recording pulse generation circuit 11 and is converted into a recording pulse train for controlling the length and width of the recording mark. These recording pulse trains are input to the laser driver 10, the recording current from the laser driver 10 causes the laser 1 to oscillate at high output, and the light emitted from the laser 1 is collimated by the lens 2 and passes through the prism 3 and the lens 4. It converges on the recording medium 6 and records a recording mark corresponding to the code string. The high frequency superimposing circuit 13 is provided to reduce laser noise caused by the laser 1, and during recording / erasing, the high frequency superimposing circuit may be suspended from the viewpoint of the life of the laser.

At the time of reproduction, the laser 1 is oscillated at a low output and is incident on the recording medium 6. Further, part of the light reflected by the prism 3 enters the photodetector 8. The output signal of the photodetector 8 is amplified by the preamplifier 17 and input to the power monitoring circuit 18. In order to keep the laser power during reproduction almost constant, a control signal is input from the power monitoring circuit 18 to the laser driver 10, and the laser drive current is controlled so that the reproduction power becomes constant. The reflected light from the recording medium 6 is made incident on the photodetector 9 with its optical path separated by the prism 3. The output signal of the photodetector 9 is amplified by the preamplifier 19, and the reproduction circuit 20
To the servo circuit 24. The reproduction circuit 20 is composed of a waveform equalization circuit, an automatic gain control circuit, a binarization circuit, etc., and the inputted reproduction signal is used as a binarized signal. The binarized signal from the reproduction circuit 20 is input to a PLL (Phase Locked Loop) circuit 21 for self clocking. The reproduction clock synchronized with the binarized signal and the binarized signal obtained by the PLL circuit 21 are input to the discrimination circuit 22 for data discrimination, and the resulting data discrimination signal is input to the controller 16 and the data is Demodulated. Recording and reproducing information using an externally applied magnetic field,
In a magneto-optical disk device for erasing, an external magnetic field generator 7 is provided and the direction of the magnetic field is switched during recording / erasing to irradiate recording / erasing power. During reproduction, a beam splitter (not shown) placed in front of the photodetector 9 separates the reflected light into p-polarized light and s-polarized light, and the photodetector 9 having a two-divided light-receiving region detects them individually. Then, a magneto-optical signal can be obtained by making each of them differential. Further, the focus error signal and the track error signal can be obtained by the photodetector 9 having the cylindrical lens (not shown) arranged in front of the photodetector 9 and the four-divided light receiving region.

During the trial writing process, the reproduced signal in the analog signal state is guided from the reproducing circuit 20 to the trial writing pattern center level detecting circuit 23. As the recording pattern used during the trial writing process, a combination pattern of the highest frequency closest pattern and the lowest frequency closest pattern in the device is used, and the center level of the closest pattern and the center level of the closest pattern are tested in the reproduced signal. The writing pattern center level detection circuit 23 detects the difference, and the controller 16 detects the difference between the center levels. The recording power when the difference becomes 0 is determined to be the optimum recording power, and normal recording is performed.
As described above, by performing trial writing, it is possible to record a highly accurate recording mark by always setting the optimum power.

FIG. 7 shows an embodiment of the test write pattern center level detection circuit 23. Here, a low-pass filter 23a is provided for the reproduction signal from the reproduction circuit 20 to detect the average level of the reproduction signal, and thereafter, two sample hold circuits 23b and 23c are used to detect the respective patterns. detecting the V _1, V ₂ as the mean level, further differential amplifier 23d
Then, ΔV (recording condition deviation signal) is input to the controller 16.

Further, the servo circuit 24 is a preamplifier 19
The actuator 5 is driven on the basis of the focus error signal and the track error signal from to control the light spot position. In the trial writing process for optimizing the servo (focus and tracking), the controller 16 monitors the focus error signal and the track error signal of the servo circuit 24, applies an electrical offset in the focus and track directions, and detects the light spot. Change the position of. The optimum recording power for each electric offset is obtained and compared by the recording pattern and the detection method described above, and the electric offset when the optimum recording power is the lowest is applied, whereby the optimum light spot position control becomes possible.

Next, an operation example of the trial writing processing procedure in this embodiment will be described with reference to the flowchart of FIG.
The device is operated by turning on the power supply of the device (step 101). First, it is determined whether or not the recording medium 6 is loaded in the apparatus, and if there is no recording medium 6, the standby state is left as it is. If the recording medium 6 is set in the device,
The recording medium 6 is rotated and the laser is emitted (step 102). Next, servo (auto focus: AF, tracking: TR) for controlling the light spot is started (step 103). Since the servo follows the target point of the device (the state where the error signal is electrically suppressed), it is not always the optimum state for actual operations such as recording / reproducing / erasing.

In order to confirm the compatibility between the inserted recording medium 6 and the apparatus, a trial writing operation is performed. The trial writing in the present embodiment is performed by the recording sensitivity variation with respect to the recording medium 6 due to the thickness variation of the recording medium 6 and the environmental temperature variation, and the relative recording sensitivity due to the state change of the apparatus (laser emission state, light spot position control state, etc.). The recording power, the recording pulse, the electric offset of AF and TR, etc. are controlled so as to minimize the fluctuation of the recording mark caused by the fluctuation, and the recording condition deviation signal is detected from the reproduction signal to set the optimum recording state. . First, in order to determine the recording conditions for the input recording medium 6, the AF offset remains at the initial value A (A is a value of 0 to 1 μm, for example), and the recording power is changed sequentially to obtain the first optimum recording power P. _A is obtained (step 104). Next, the recording power is sequentially changed while the AF offset is applied to A + K, and the second optimum recording power P
_{A + K} is calculated (step 105 to step 106). P
_A is compared with P _{A + K} (step 107), P _{A + K} ≧ P _A
If so, then the recording power is sequentially changed in the state where the AF offset is applied _AK (step 108), and the third optimum recording power P _AK is obtained (step 109). P
Compare _A with P _AK (step 110), P _AK ≧ P _A
If so, the initial value A is obtained as the optimum value of the AF offset,
The final optimum recording power at this time is P _A (step 111).

The second optimum recording power P _{A + K} is obtained and P
_{When A} and P _{A + K} are compared (step 107 above), P
_{If A + K} ≧ P _{A is} not satisfied, AF offset is further added by + K and applied as A + 2K (step 113) to obtain the optimum recording power P _{A + 2K} (step 114), and P _{A + K}
(Step 115). If P _{A + 2K} ≧ P _{A + K, the} offset is sequentially changed (step 11
7) The operations of steps 114 and 115 are repeated, and when P _{A + nK} ≧ P _{A + (n-1) K} (n is a natural number) is satisfied, the optimum value of the AF offset is A + (n-1) K. P _{A + (n-1) K} is obtained as the final optimum recording power (step 116).

When the third optimum recording power P _AK is obtained and P _A and P _AK are compared (step 110),
If P _AK ≧ P _{A, the} AF offset is further added by −K and applied as A−2K (step 112), and the trial writing in step 109 is executed to obtain the optimum recording power P.
_{Find A-2K} and compare with P _AK (step 11 above)
0). If P _A-2K ≧ P _{AK is} not satisfied, the above operation (step 112, step 109) is repeated _until P _A-nK ≧ P
_{When A- (n-1) K} (n is a natural number) is satisfied, the optimum AF offset value is A- (n-1) K, and the final optimum recording power is P _{A- (n-1) K.} (Step 111).

When the optimum value of the AF offset and the final optimum recording power are obtained, a trial writing end signal is output to start the next operation of the apparatus. The optimum value of the AF offset obtained is set as an initial value for the next trial writing operation.

The trial writing operation is performed when the recording medium 6 is attached to the apparatus or when the apparatus is powered on while the recording medium 6 is attached, and information is recorded in the normal operation state of the apparatus. Perform when recording / playback cannot be performed accurately. Since the sensitivity of the recording medium 6 is different between the inner circumference and the outer circumference, and the sensitivity change of the recording medium 6 occurs due to the temperature change inside the apparatus, in order to compensate for these, the inner circumference, the middle circumference, It is desirable to perform this at regular intervals on the outer circumference. However, it is desirable to minimize the time required for trial writing when using the device.

As described above, the information of the optimum recording power and the optimum focus servo state can be obtained by variously changing the AF offset state and recording / reproducing a predetermined pattern while changing the recording power in each AF offset state. The correction based on the recording power is applied to each recording medium 6
Only the change in the recording sensitivity of the recording medium 6 due to the variation in the recording sensitivity for each time and the change in the environmental temperature is changed.
For example, even the change in recording sensitivity due to the change in AF offset is not corrected by the recording power. Therefore, the problem that the fluctuation range of the optimum recording power becomes large and correction cannot be performed due to the limit of the output of the laser 1 or the like is solved.

Since the focus position of the laser beam is always on the recording medium 6 and the recording power is always optimum, it is possible to suppress the fluctuation of the recording mark and form the recording mark with high accuracy. The recording density of information can be improved.

FIG. 3 is a flow chart showing an example of the timing of trial writing in the present embodiment. After the recording medium 6 is mounted (step 121), the test writing of the procedure of FIG. 2 is first performed on the outer periphery of the recording medium 6 to obtain the final optimum recording power, which is set to P _0, and the optimum value of the AF offset is A _0.
(First trial writing) (step 122). Next, in the middle and inner circumferences, the procedure up to the step of obtaining the first optimum recording power P _A in the procedure of FIG. 2 is performed, and P _A is made the final optimum recording power. The AF offset remains A ₀ . That is, the difference between the optimum values of the AF offsets on the inner circumference, the middle circumference, and the outer circumference of the recording medium 6 is usually small and can be ignored (second trial writing) (steps 123 to 12).
4). Variations in sensitivity can be compensated by interpolating the final optimum recording power at each position in the radial direction of the recording medium 6 using the final optimum recording powers obtained at the inner circumference, the middle circumference, and the outer circumference.

In ZCAV, the final optimum recording power may be interpolated and determined for each zone from the final optimum recording powers obtained in the inner circumference, the middle circumference and the outer circumference.

Then, the time is monitored by the timer (step 125), and after T ₁ time, the trial writing of the procedure of FIG. 2 is performed on the outer circumference to obtain the final optimum recording power P ₁ (first trial writing) (step 126). . A in the middle and inner laps
The F offset is fixed, and the procedure up to the step of obtaining the first optimum recording power P _A in the procedure of FIG. 2 is performed (second trial writing).
(Step 127-Step 128). It is determined whether the difference between P ₁ and P ₀ is less than or equal to the specified value m (step 129), and m
Unless otherwise, the above operation (second trial writing) (step 125 to step 128) is repeated after T ₁ time.

When the difference between P ₁ and P ₀ is less than or equal to the specified value m in the determination of step 129, the monitoring time is extended by T ₁ hour (step 130), the time is monitored by the timer, and 2T ₁ hours later (step 131), the procedure up to the step of obtaining the first optimum recording power P _A in the procedure of FIG. 2 is performed on the outer circumference to obtain the final optimum recording power P ₂ (second trial writing) (step 132).

It is judged whether or not the difference between P ₂ and P ₁ is less than or equal to a prescribed value m (step 133). When it is less than m, the monitoring time is further extended by T ₁ time (step 134), 3T ₁
After the lapse of time, the same operation as described above (step 131 to step 1)
33) is performed.

As described above, when the trial writing is repeatedly performed, depending on the variation of the optimum recording power from the last time,
It is accurately determined whether to perform both the first and second trial writings, only the second trial writings, or omit the second trial writings. Since the length is appropriately changed according to the fluctuation of the optimum recording power, it is possible to prevent useless trial writing from being executed even though the recording sensitivity of the recording medium 6 is stable.
The time required for trial writing can be shortened. Therefore, for example, the recording / reproducing speed of the information including the trial writing on the recording medium 6 is improved, and the information transfer rate with the host can be further increased.

Further, in ZCAV, the test writing to be performed after 2T ₁ hour is performed in the nearest zone without performing the test writing in the outer periphery, and the final optimum recording power in that zone is compared. The operation of may be performed.

FIG. 4 shows an example of a recording method for recording information on a recording medium in the information recording / reproducing apparatus of this embodiment. Here, a case where a (1,7) RLL code is adopted as a modulation method will be described. The code string modulated according to the regular information data from the controller 16 described in FIG. 1 and the code string from the trial writing pattern generation circuit 15, and the output from the selector 12 is the recording code string. This recording code string is 2T _{W in} the case of (1,7) RLL code.
There are seven types of 8T _W , and NRZI (Non Re) whose polarity is inverted by the modulation code "1" for mark edge recording.
turn ToZero Inverse) signal. Here, T _W represents the window width, and the synthesizer 14
The reference clock period oscillating at is equal to T _W. When recording / reproducing a 5-inch optical disc at 3000 rpm, if the recording pit length is 0.75 μm, (1,7) RL
The L code can realize a transfer rate of 2 MB / s in the inner circumference and 4 MB / s in the outer circumference, and T _W at this time is 40 n in the inner circumference.
s, 20 ns at the outer circumference. The recording pulse generation circuit 11 generates a recording pulse train corresponding to the pulse portion of the recording code train. The recording pulse train consists of the first pulse and 2
Different lengths of th and subsequent pulses, the first pulse is a pulse width of 3 / 2T _W against the shortest pulse width 2T _W, 1/2
Shorten by T _W. The pulse width after 3T _W is the first pulse 3
/ 2T _W and obtained by going adding the combination (same as the reference clock waveform) of the second and subsequent pulse width 1 / 2T _W and the gap width 1 / 2T _W. These pulses are generated in synchronization with the reference clock. This improves the control of pulse width and pulse interval.

FIG. 5 shows an example of the recording mark shape, recording waveform and control signal in the information recording / reproducing apparatus of this embodiment. The recording waveform is composed of a combination of a recording pulse train and a gap, and a quiescent period of a time width is provided by the recording pulse train B at the trailing edges of the recording pulse trains A and C. Recording pulse train B
By providing a gap with a certain time width (for example, T _W ) from the trailing edge of the recording code train, the heat from the last trailing edge of the recording pulse train hardly changes the temperature at the leading leading edge of the next recording pulse train. To do so. The laser power is set to five power levels. The reproduction power Pr at the time of reproduction, the reproduction power Pr ′ when the reproduction power is lowered by the modulation degree to suspend the high frequency superposition at the time of recording, and the recording power by the recording pulse train B are P.
a, the recording power by the recording pulse train A is Pw1, and the recording power by the recording pulse train B (the second and subsequent rear pulses) is Pw2. During playback, power monitoring circuit 1
The variation of the reproduction power is monitored by 8 and is fed back to the laser 1 to keep the reproduction power Pr during reproduction constant. The head pulse (3/2 Tw pulse) in this recording waveform
Is set to be lower than the power of the rear pulse (1/2 Tw pulse). By doing so, the recording mark width by the head pulse and the recording mark width by the rear pulse can be made equal, and the recording mark length can be controlled with high accuracy. This is because the temperature on the recording medium 6 due to the leading pulse and the temperature due to the backward pulse are constant, and the recording mark width is constant, so that the reproduction signal amplitude of the data portion obtained by reproducing the recording medium 6 is constant. Can be
The binarized signal can be generated by slicing directly at the center of the reproduced signal or at a certain level. Further, by using the combination of the recording pulse train and the recording auxiliary pulse, the recording power Pa by the recording pulse train B can be used as the erasing power in the overwritable magneto-optical disk with the exchange coupling film described in JP-A-62-175948. Overwriting can be realized by setting the recording powers Pw1 and Pw2 by the recording pulse trains A and C.

FIG. 6 shows an example of a test writing pattern detection method used in the information recording / reproducing apparatus of this embodiment. As the test writing pattern, the closest pattern with the highest frequency in the device (2 in the case of (1,7) RLL code)
Is a T _W) and the lowest frequency to use a repeating pattern of the most sparse pattern (8T _W). For mark edge recording,
It is important to control the time axis of the recording marks, and the time axis of each pattern was controlled when the center levels of the reproduction signals of the densest pattern and the sparsest pattern were equal. To do. As described above, in this embodiment, the time base fluctuation is detected by the amplitude level fluctuation.

A reproduced signal obtained by recording and reproducing the above-described test writing pattern under a certain condition is shown in FIG. 6 (a). In the test writing pattern center level detection circuit 23 of FIG. 1, the center level (V ₁ ) of the closest pattern and the center level (V ₂ ) of the most sparse pattern are detected from the reproduced signal, and the voltage difference ΔV between them is detected.
= Determine the V ₁ -V _2. Center level V _{1 of the} closest pattern
6B is determined by the sample pulse 1 and the timing of detecting the center level V ₂ of the sparsest pattern is determined by the sample pulse 2. ΔV is input to the controller 16 as a recording condition deviation signal and finds a recording condition that ΔV = 0.

An example of detection of trial writing is shown in FIG.
The recording power is sequentially increased from P1 to P9. At the time of reproduction, ΔV corresponding to each recording power can be obtained as described above. The controller 16 determines the recording power P5 at which ΔV≈0 as the optimum recording power. Next, when the AF offset is applied from V1 to V9, FIG.
The change of the optimum recording power obtained by (c) of (3) is shown in (d) of FIG. The initial state of the AF offset is V5. Since the optimum recording power has a minimum value because the energy of the laser beam is effectively flown into the recording medium 6 when the light spot is most narrowed down, the controller 16 can determine this minimum value to optimize the AF offset. Case V6 is selected by the controller 16.
Next, the controller 16 commands the servo circuit to set the AF offset to V6, and the servo circuit 24 drives the actuator 5. By performing such trial writing, the optimum recording power and the optimum servo state can be realized.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, the recording medium is not limited to an optical disc or the like, but can be widely applied to general recording media in which information is recorded and reproduced by irradiation of light.

The servo state is not limited to the focus servo state, but may be applied to the tracking servo state.

[0040]

According to the information recording / reproducing method of the present invention, it is possible to suppress the recording sensitivity variation with respect to the recording medium due to the film thickness variation of the recording medium and the environmental temperature variation and the recording sensitivity variation due to the information recording / reproducing apparatus, and to perform the information recording / reproducing. Since the compatibility between the device and the recording medium can be improved and the recording mark can be controlled with high accuracy, the reliability of the information recording / reproducing device, the recording capacity, and the information transfer rate can be improved. .

Further, according to the information recording / reproducing apparatus of the present invention, the recording sensitivity variation with respect to the recording medium due to the film thickness variation of the recording medium and the environmental temperature variation and the recording sensitivity variation by the information recording / reproducing apparatus are also suppressed, and the information recording / reproducing is performed. Since the compatibility between the device and the recording medium can be improved and the recording mark can be controlled with high accuracy, the operation reliability, the recording capacity, and the information transfer rate can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of the configuration of an information recording / reproducing apparatus that is an embodiment of the present invention.

FIG. 2 is a flowchart showing an example of a trial writing processing procedure in the information recording / reproducing method and apparatus according to the embodiment of the present invention.

FIG. 3 is a flowchart showing an example of a trial writing processing procedure in the information recording / reproducing method and apparatus according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram of a recording code string and a recording pulse string used in the information recording / reproducing method and apparatus which are one embodiment of the present invention.

FIG. 5 is an explanatory diagram showing an example of recording mark shapes and recording waveforms used in the information recording / reproducing method and apparatus according to an embodiment of the present invention.

FIG. 6 is a diagram showing an example of the operation of the information recording / reproducing method and device according to one embodiment of the present invention.

FIG. 7 is a block diagram showing an example of a configuration of a test writing pattern center level detection circuit in the information recording / reproducing apparatus which is an embodiment of the present invention.

[Explanation of symbols]

10 ... Laser driver, 11 ... Recording pulse generation circuit, 1
5 ... Trial writing pattern generation circuit, 16 ... Controller,
20 ... Regeneration circuit, 21 ... PLL circuit, 22 ... Discrimination circuit,
23 ... Trial writing pattern center level detection circuit, 24 ... Servo circuit.

Claims (5)

[Claims] 1. A method of recording data of a predetermined pattern at a predetermined position of a recording medium, performing a trial writing operation for obtaining information of an optimum recording power and an optimum servo state from a reproduced signal of the recorded data, and then performing the operation. An information recording / reproducing method for starting regular recording on a recording medium, wherein the servo state is changed, and the data of a predetermined pattern is recorded / reproduced while changing the recording power in each of the servo states. An information recording / reproducing method characterized by performing a first trial writing for obtaining information on a servo state. 2. The first trial writing and the servo state are fixed to the optimum servo state obtained by the first trial writing, and the data of a predetermined pattern is recorded / reproduced while changing the recording power. 2. The information recording / reproducing method according to claim 1, wherein the information recording / reproducing method is performed by arbitrarily combining with a second trial writing for obtaining information of recording power. 3. In the first trial writing, recording power for recording and reproducing data composed of at least two types of patterns while changing recording power, and recording power at which a deviation signal between the two or more types of patterns becomes substantially zero. 3. The servo state and the recording power when the recording power becomes the minimum are respectively set as the optimum servo state and the optimum recording power by obtaining and comparing the respective servo states. Information recording and reproducing method described. 4. The optimum recording power obtained by the first or second trial writing is compared with the optimum recording power obtained by the trial writing performed before, and when the difference is within a predetermined value, A first operation in which the test writing to be performed next is the second test writing, and when the difference exceeds a predetermined value, the test writing to be performed next is the first test writing, a plurality of positions of the recording medium. When trial writing is performed on the first test writing, the first trial writing is performed at a predetermined position and the second test writing is performed at other positions.
The second operation of performing the trial writing, the optimum recording power obtained by performing the first trial writing at the predetermined position was obtained by the first trial writing performed at the predetermined position before that. When the difference is within a predetermined value as compared with the optimum recording power, the test writing to be performed at a predetermined position next is set as the second test writing, and the test writing operation at other positions is omitted. A third operation in which when the difference exceeds a predetermined value, the test writing next performed at a predetermined position is set as the first test writing, and the second test writing is performed at another position. The first or second trial writing is performed every predetermined time, and the optimum recording power obtained by the first or second trial writing is obtained by the first or second trial writing performed before that. Compared with the optimum recording power, Then, when repeating the second trial writing, a fourth operation is performed to make the time until the second trial writing next be longer than a predetermined time, and the first or second trial writing is performed in a predetermined manner. The optimum recording power obtained by performing the first or second trial writing at a predetermined position at a predetermined position was obtained by the first or second trial writing performed at a predetermined position before that. When the difference is within a predetermined value as compared with the optimum recording power and the second trial writing is repeated at a predetermined position, the time until the second trial writing to be performed next is longer than the predetermined time. 3. The information recording / reproducing method according to claim 2, wherein at least one of the fifth operation to perform is executed. 5. An information recording / reproducing apparatus for condensing light on a recording medium to record / reproduce information, wherein data of a predetermined pattern is recorded at a predetermined position on the recording medium prior to the recording / reproduction of the information. And a control device for starting the normal recording of the information on the recording medium after performing a test writing operation for obtaining information of the optimum recording power and the optimum servo state from the reproduced signal of the recorded data. An information recording / reproducing apparatus, wherein the control device has a control logic for executing the information recording / reproducing method according to claim 1, 2, 3, or 4.