KR100684403B1 - Recording power compensation method of optical disk device - Google Patents

Abstract

The present invention relates to a recording power compensation method of an optical disk apparatus, comprising: a first step of detecting and storing optimum recording power and corresponding recording signal characteristics through an OPC operation; A second step of rewriting test data having a predetermined size by applying the detected optimal recording power; Detecting a recording signal characteristic of the rewritten test data and comparing the recording signal characteristic with the detected stored recording signal characteristic; And a fourth step of compensating recording power according to the comparison result, while rewriting the test data having a predetermined size in the next test area while maintaining the optimal recording power detected through the OPC operation, and detecting β from the following test area. It is a very useful invention that the best recording quality can be obtained by the compensated optimal recording power by compensating the optimal recording power previously detected through the comparison result between the value and the optimum detected β value.

OPC, β value, recording power compensation, optimal recording power, EEPROM

Description

Method for compensating writing power of optical disc device             

1 illustrates a variable example of recording power during an OPC operation;

2 is a block diagram of an embodiment of an optical disk device in which the recording power compensation method of the optical disk device according to the present invention is implemented.

3 and 4 show the flow of a preferred embodiment of the recording power compensation method of the optical disk apparatus according to the present invention.

※ Explanation of code for main part of drawing

M: Spindle Motor 10: Optical Disc

20: optical pickup 30a: digital recording signal processing unit

30b: digital reproduction signal processor 40: channel bit encoder

41: optical drive 50: R / F section

60: servo unit 61: drive unit

70: micom 71: memory

The present invention relates to a recording power compensation method of an optical disk device, and more particularly, to a method of compensating and recording an optimal recording power detected through an OPC operation.

In a typical optical disk device, an optimal power is detected through an OPC (Optimum Power Calibration) operation and the detected optimal recording power is applied and recorded. The OPC operation for a recordable optical disc (for example, DVD-R) is briefly described. The explanation is as follows.

First, test data of a predetermined size is recorded in a test area of the optical disc. As an example of this, the recordable optical disc (DVD-R) is recorded in one ECC block (16 sectors) in each OPC operation. In this case, as shown in FIG. 1, recording power based on recording power corresponding to a target β value βtarget defined for the manufacturer of the optical disc (hereinafter referred to as 'reference recording power Pref'). Are recorded by varying the predetermined size (for example, Pref ± 0.6 mW).

When the recording of the test data is completed, the test data is sequentially read to detect a beta value from the reproduced RF signal for the read test data. The beta value is a value representing the asymmetry of the reproduced RF signal. The value of β and the recording power are in proportional relationship.

When the detection of the β value is completed, a function of a curve is fitted by each recording power obtained with the detected β value, and then from the curve obtained as described above and a target β value predefined for the manufacturer of the optical disc. The optimum recording power Popt is detected and the requested recording operation is performed by applying the detected optimal recording power when the recording operation is requested.

However, since the beta value detected through the OPC operation is usually inferior due to the influence of optical pickup or hardware noise, the best recording quality is not obtained even with the optimum recording power obtained through the OPC operation. There was a problem.

Therefore, the present invention was created to solve the above problems, by applying the optimum recording power detected through the OPC operation to rewrite the test data of a predetermined size in the next test area, and to record the recording signal for the rewritten test data. The recording power of the optical disk apparatus which compares the characteristics with the optimal recording signal characteristics corresponding to the detected optimal recording power and compensates for the optimal recording power detected therefrom, thereby obtaining the best recording quality by the compensated optimal recording power. The purpose is to provide a compensation method.

According to an aspect of the present invention, there is provided a recording power compensation method of an optical disk device, the method comprising: detecting and storing an optimum recording power and corresponding recording signal characteristics through an OPC operation; A second step of rewriting test data having a predetermined size by applying the detected optimal recording power; Detecting a recording signal characteristic of the rewritten test data and comparing the recording signal characteristic with the detected stored recording signal characteristic; And a fourth step of compensating recording power according to the comparison result.

In addition, the first step of detecting and storing the optimum recording power and the corresponding recording signal characteristics through the OPC operation; A second step of rewriting test data having a predetermined size by applying the detected optimal recording power; Detecting a recording signal characteristic of the rewritten test data and comparing the recording signal characteristic with the detected stored recording signal characteristic; And a fourth step of compensating the recording power by the amount of change in the recording power corresponding to the difference between the two recording signal characteristics, in accordance with the comparison result.

Best Mode for Carrying Out the Invention A preferred embodiment of a recording power compensation method of an optical disk apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a block diagram of an embodiment of an optical disk device (for example, a DVD recorder) in which a recording power compensation method of the optical disk device according to the present invention is implemented, and includes an error correction code (ECC), etc. A digital recording signal processing unit 30a which adds and converts into a recording format; A channel bit encoder (40) for reconverting the data converted into the recording format into a bitstream; An optical driver 41 for outputting a light quantity driving signal according to the input signal; An optical pickup (20) for recording a signal on the optical disc (10) in accordance with the light quantity driving signal and for detecting a recording signal from the recording surface; An R / F unit 50 for shaping the signal detected by the optical pickup 20 and outputting it as a binary signal; A drive unit 61 for driving the spindle motor M for rotationally driving the optical pickup 20 and the optical disc 10; A servo unit 60 controlling the driving of the drive unit 61 from the tracking error signal T.E and the focus error signal F.E of the optical pickup 20 and the rotation speed of the optical disc 10; A digital reproduction signal processor (30b) for restoring the binary signal to original data with its own clock synchronized with the binary signal; The optimal recording power (Popt) detected through the OPC operation and the corresponding optimum β value (βopt), and the memory (EEPROM) in which each recording power and the corresponding β value used in the OPC operation are stored in a table form 71; And rewriting test data in the next test area by applying the detected and stored optimal recording power (Popt) through the OPC operation, and comparing the detected β value and the previously detected and stored optimal β value (βopt) according to the comparison result. The microcomputer 70 compensates for the optimal recording power Popt and performs a recording operation with the compensated optimal recording power.

3 and 4 illustrate a flow of a preferred embodiment of the recording power compensation method of the optical disk apparatus according to the present invention, hereinafter with reference to the configuration of FIG. The power compensation method will be described in detail.

First, when the recordable optical disc (for example, DVD-R) 10 is inserted and seated (S10), the microcomputer 70 performs an OPC operation in a test area of the optical disc 10. As shown.

Through the OPC operation, the microcomputer 70 detects and sets an optimum recording power Popt (S11), while the detected optimal recording power and the corresponding optimal β value βopt are used for the OPC operation. The respective recording powers and the respective β values corresponding to the respective recording powers and store them in the memory 71 in the form of a table (S12). The microcomputer 70 stores the stored recording powers and the corresponding β values. From this, it is possible to easily detect the amount of change in recording power in accordance with the amount of change in β value.

Upon completion of the OPC operation, the microcomputer 70 rewrites the test data in the next test area by applying the optimal recording power Popt detected and stored through the OPC operation (S13). In this case, the detection is performed without changing the recording power. The test data of a predetermined size (eg, within a 1 ECC block) is rewritten while maintaining the stored optimal recording power Popt. When the test data rewriting is completed, the microcomputer 70 performs the rewriting of the test data. The β value is detected from the reproduced RF signal (S14). At this time, if the detected β value is different even though the recording power of the same size (optimal recording power Popt) is recorded, the average β value is detected.

Meanwhile, in the exemplary embodiment of the present invention, the optimal β value βopt corresponding to the optimal recording power Popt detected through the OPC operation is 2%, and the β value detected through the test data rewriting is 5%. Assume that

Subsequently, the microcomputer 70 compares the detected β value (5%) with the optimum β value βopt (2%) (S15) to determine whether recording power is compensated from the difference between the two values. The microcomputer 70 detects the difference between the two values β and performs a recording power compensation operation when the detected difference between the two values β is greater than or equal to a predetermined value.
The predetermined constant value is a value set to determine whether a recording power compensation operation is required or a recording power compensation operation is not required with a difference (change amount) comparing the detected β value with an optimum β value. The value is arbitrarily set by the system manufacturer or the optical disk manufacturer based on the experimental value or the like. Accordingly, the predetermined constant value may be expressed as a value for determining whether to record power compensation.

As an example of compensating the recording power, the difference between the two β values is greater than or equal to a value for determining whether the recording power is compensated. If the β value detected through the rewriting of the test data is larger than the optimum β value (S20), The microcomputer 70 determines that the recording power is set high, and adjusts the current recording power down to compensate (S21). If the detected β value is smaller than the optimum β value (S30), the test data is rewritten. The microcomputer 70 determines that the recording power is set low and compensates by adjusting the current recording power upward (S31).

On the other hand, when compensating the recording power, the microcomputer 70 changes the amount of change in the recording power (for example, 0.6 mW) corresponding to the difference between the amount β values, that is, the amount of change of the β value (3%). ), And by adjusting the detected change amount of the recording power as the power compensation value, the current recording power is adjusted downward or upward as described above to compensate.

As described above, when the recording operation is requested in the state in which the recording power is compensated (S40), the microcomputer 70 performs the requested recording operation until the end of the recording by applying the compensated recording power (S41, S50).

In the above embodiment, if the difference of the amount β value is not more than the value for determining whether or not to compensate the recording power, the microcomputer 70 is applied until the end of the recording by applying the currently set recording power without compensation of the recording power The recording operation is performed (S41, S50).

In the above-described embodiment of the present invention, the recording power is typically recorded in one sector unit while varying the recording power and compared with the β value detected therefrom. The idea is that the precision is much higher.

The above-described preferred embodiments of the present invention are disclosed for purposes of illustration, and those skilled in the art can improve, change, and substitute various other embodiments within the technical spirit and scope of the present invention disclosed in the appended claims below. Or addition may be possible.

According to the recording power compensation method of the optical disk apparatus according to the present invention, the test data having a predetermined size is rewritten in the next test area while maintaining the optimal recording power detected through the OPC operation. It is a very useful invention that the best recording quality can be obtained by the compensated optimum recording power by compensating the optimal recording power detected through the comparison result of the detected optimum β value.

Claims (13)

delete delete delete delete delete delete delete delete A first step of associating and storing the respective recording powers used in the OPC operation for recording test data in the test area of the optical disc while varying the recording powers and corresponding recording signal characteristics thereof; A second step of detecting an optimum recording power and a corresponding optimal recording signal characteristic through the OPC operation; A third step of rewriting test data by applying the detected optimal recording power; A fourth step of detecting a recording signal characteristic with respect to the rewritten test data, and detecting a change amount by comparing the detected recording signal characteristic with an optimal recording signal characteristic; And And a fifth step of detecting a change amount of the recording power corresponding to the change amount of the characteristic of the recording signal from the storage information, and compensating the recording power by using the change amount of the recording power as a compensation value. Compensation Method. The method of claim 9, The recording signal compensation method of the optical disc apparatus, characterized in that the characteristic of the recording signal is a β value representing the degree of asymmetry of the reproduction RF signal. The method of claim 10, The compensation of the recording power in the fifth step may include: when the recording signal characteristic? Value detected in the fourth step is larger than the optimal recording signal characteristic? A recording power compensation method of an optical disc apparatus, characterized in that the recording power is adjusted downward by an amount of change in recording power corresponding to a change in recording signal characteristic. The method of claim 10, The compensation of the recording power in the fifth step may include: when the recording signal characteristic? Value detected in the fourth step is smaller than the optimum recording signal characteristic? Value by a predetermined value (a value for determining whether or not recording power compensation is performed), A recording power compensation method for an optical disc apparatus, characterized in that the recording power is adjusted upward by an amount of change in recording power corresponding to the amount of change in recording signal characteristics. The method of claim 9, And the third step is to rewrite test data while maintaining the detected optimum recording power.

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