KR100588172B1 - Method for detecting optimal writing power in optical disc driver - Google Patents

Abstract

The present invention relates to a method of detecting an optimum recording power of an optical disk device that detects an optimum recording power from the recording quality (jitter amount) of recording data during an OPC operation. The present invention relates to a method for detecting test data while varying the recording power around a predetermined reference power. The first step to do; A second step of reproducing the recorded test data and detecting a jitter amount therefrom; And a third step of confirming the change in the detected jitter amount and determining the optimum recording power therefrom by detecting or re-executing OPC, wherein the optimum recording power is detected from the jitter amount of the recording data during OPC operation, if recording If the amount of jitter in the data continues to increase or decrease, the target power is varied, and then the OPC operation is performed again to detect the optimal recording power, so that the optimal recording power for each set is determined even if the optical characteristics between the sets are slightly different. This is a very useful invention in which the optimum recording quality can be obtained.

OPC, Beta, Gamma, Record Power, Jitter,

Description

Method for detecting optimal writing power in optical disc driver             

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

2 is a flowchart illustrating a preferred embodiment of a method of detecting an optimal recording power of an optical disk apparatus according to the present invention.

3 illustrates an example of jitter characteristics of data recorded through an OPC operation.

※ Explanation of code for main part of drawing

10: optical disc 20: optical pickup

30a: digital recording signal processor 30b: digital reproduction signal processor

40: channel bit encoder 41: optical driver

50: R / F section 60: servo section

61 drive unit 70 jitter detection unit

80: micom

The present invention relates to an optimal recording power detection method of an optical disc apparatus which detects an optimum recording power from the recording quality (jitter amount) of recording data during an OPC operation.

In general, in the microcomputer of the optical disk device, the target beta (Target β), the target gamma (Target γ), the target power (reference power) values by recording speed by disk manufacturer (disk code) are stored in the form of firmware. Accordingly, the microcomputer detects the optimal recording power through an OPC (Optimal Power Calibration) operation using the preset stored values when the optical disc is inserted and inserted, and β values for the optical disc (CD-R) that can be written once, For the rewritable optical disc (CD-RW), the OPC operation is performed by using the? Value.

Hereinafter, an OPC operation process for the CD-R will be briefly described.

When the optical disc (CD-R) is inserted and mounted, the microcomputer changes the recording power by a predetermined size based on a target power set for the disc code and OPC recording speed of the inserted optical disc, and performs PCA (Power Calibration) of the optical disc. Test data is recorded in the test area in the test area. In general, the test area is composed of 100 partitions, and each partition is composed of 15 frames. In one OPC operation, one of the partitions is used to partition a partition. 15 frames are recorded with 15 recording powers.

When the recording of the test data is completed, the recorded test data is sequentially read to detect a beta value from the reproduced RF signal. The beta value is a value representing the asymmetry of the reproduced RF signal. .

After the detection of the beta value is completed, fitting a function of the curve by each recording power at which the detected beta value is obtained, and then setting a target beta value for the curve obtained as described above, the disc code and the OPC recording speed of the optical disc. The optimum recording power is detected from the C1, and the recording operation is performed by applying the detected optimal recording power later.

However, although the characteristics of the optical system are slightly different for each optical disk device, in the related art, the optimum recording power is detected and recorded using the target gamma and target beta values which are detected and stored for each optical disk manufacturer as described above. There was a problem that could be degraded.

According to an aspect of the present invention, there is provided a method of detecting an optimal recording power of an optical disk device, the method comprising: recording test data while varying recording power around a preset reference power; A second step of reproducing the recorded test data and detecting a jitter amount therefrom; And a third step of confirming the change of the detected jitter amount and determining the optimum recording power therefrom by detecting or re-performing OPC.

According to an aspect of the present invention, there is provided a method of detecting an optimal recording power of an optical disk device, the method comprising: recording test data while varying recording power around a preset reference power; A second step of confirming recording quality by reproducing the recorded test data; And a third step of determining whether to re-perform the first step according to the confirmation result.

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of the optimal recording power detection method of the optical disk apparatus which concerns on this invention is described in detail based on attached drawing.

1 is a block diagram of an embodiment of an optical disk device in which an optimal recording power detection method according to the present invention is implemented. The digital recording signal converts an input digital data into a recording format by adding an error correction code (ECC) or the like. A processing unit 30a; 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) according to the light quantity driving signal and for detecting a recording signal; An R / F unit 50 for shaping the signal detected by the optical pickup 20 and outputting it as a binary signal; A digital reproduction signal processor (30b) for restoring and outputting the binary signal to original data with its own clock synchronized with the 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 for controlling driving of the drive unit 61 from a tracking error signal TE and a focus error signal FE of the optical pickup 20 and a rotational speed of the optical disc 10; A jitter detector (70) for detecting the amount of jitter from the binary signal; And performing an OPC operation using a target power (reference power) value, which is pre-stored for each recording speed per disc manufacturer (by disc code), and detecting an optimum recording power from the jitter amount detected during the OPC operation. It is configured to include a microcomputer 80 to control and perform the recording operation by applying this.

FIG. 2 is a flow chart illustrating a preferred embodiment of a method of detecting an optimal recording power of an optical disk device according to the present invention. Hereinafter, the method of detecting optimal recording power of FIG. 2 according to the present invention will be described with reference to the configuration of the apparatus of FIG. 1. It will be described in detail.

First, when the optical disk 10 is inserted and mounted (S10), the microcomputer 80 performs an OPC operation in a test area in the PCA area of the optical disk 10. The OPC operation process is as follows.

First, the microcomputer 80 detects a code of the optical disc 10 inserted and mounted to detect a target power stored in association with the detected code and an OPC recording speed, and detects the detected target power (for example, 10 mW) is applied to the optical driver 41 to change the recording power by a predetermined predetermined size. For example, if the detected target power is 10 mW and the preset power variable amount is 1 mW, the microcomputer ( 80) applies a control signal to the optical driver 41 which increases 7 steps by 1 mW (+ ΔP) by 1 mW and decreases (−ΔP) by 1 mW based on the target power of 10 mW.

The optical driver 41 outputs a recording signal for test data at an optical driving power corresponding to the applied control signal, and thus the optical pickup 20 records test data in the test area (S11). ), The recording signal for the test data is an EFM modulation consisting of a pulse train having a time span of 3 to 11 times the reference time width T (T is about 230 nsec at one cycle of frequency 4.32 MHz as the standard speed (1x speed)). Is a signal.

Assuming that the detected target power is 10 mW and the power variable amount is 1 mW, as a result, test data is recorded at a recording power of 3 mW to 17 mW during the OPC operation, and when recording of the test data is completed (S20). The optical pickup 20 sequentially reads the recorded test data under the control of the microcomputer 80, and the jitter detector 70 sequentially reads the output test data from the R / F unit 50. The jitter amount is detected from the reproduced RF signal (S21).

The microcomputer 80 determines whether the detected change in the amount of jitter, that is, the increase or decrease of the amount of jitter (S22), determines whether to re-execute the OPC operation, and as shown in the example of FIG. If the detected jitter amount gradually decreases and then increases again (S30), the microcomputer 80 detects and stores the recording power (11mW) at which the jitter amount is minimum as the optimal recording power (Popt) without performing the OPC operation again. (S31).

However, if the detected jitter amount continues to decrease or increase, the microcomputer 80 performs the OPC operation again. In the present invention, as in the example of FIG. This is because the recording power that minimizes the jitter amount is not known if the jitter amount continues to decrease or increase.

Accordingly, if the detected jitter amount continues to decrease or increase, the microcomputer 80 varies the detected target power by a predetermined value (for example, 6 mW) in a direction in which the jitter amount decreases (S32). If it is decreased, the microcomputer 80 increases the detected target power by a predetermined value (6mW), and when the amount of jitter continues to increase, the detected target power is decreased by a predetermined value (6mW), and the variable target power The test data is recorded while changing the recording power by a predetermined size based on the reference (S33).

On the other hand, the microcomputer 80 decreases the amount of power variation when the OPC operation is performed again than the previous OPC operation. For example, if the previous power variable amount is 1mW, the power variable amount is 0.5mW when the OPC operation is performed again. OPC operation will be performed again.

Therefore, if the detected target power is 10 mW and the detected jitter amount continues to decrease, the target power is varied to 16 mW. As a result, the target power is varied from 0.5 mW to 12.5 mW to 19.5 mW when the OPC operation is performed again. When the test data is recorded with the recording power, and the detected jitter amount is continuously increased, the target power is varied to 4 mW. As a result, when the OPC operation is performed again, the test data is recorded with the recording power of 0.5 mW to 7.5 mW. Records are made.

When the recording of the test data is completed, the optical pickup 20 sequentially reads the recorded test data under the control of the microcomputer 80, and the jitter detector 70 sequentially reads the R test data. The jitter amount is detected from the reproduced RF signal output from the / F unit 50, and the microcomputer 80 confirms the change of the detected jitter amount, so that the detected jitter amount gradually increases as in the example of FIG. If it decreases and then increases again, the recording power with the minimum jitter amount is detected and stored as the optimum recording power.

When the recording operation is requested later, the microcomputer 80 applies the detected and stored optimal recording power to perform the requested recording operation.

In the above embodiment, if the detected jitter amount continues to decrease or increase despite the re-execution of the OPC operation, and thus the optimum recording power cannot be detected, the microcomputer 80 changes the variable target power again. The OPC operation is performed again. Preferably, the OPC operation is re-executed only up to a predetermined number of times, and the power variable amount is reduced each time than the previous OPC operation.

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.

 The optimal recording power detection method of the optical disk apparatus according to the present invention as described above detects the optimal recording power from the jitter amount of the recording data during the OPC operation, but if the jitter amount of the recording data is continuously increasing or decreasing continuously. By varying the target power and then performing the OPC operation again to detect the optimum recording power, it is a very useful invention that the optimum recording quality can be obtained by the optimal recording power for each set even if the optical system characteristics between the sets are slightly different.

Claims (10)

In the method of performing OPC of the optical disk device, A first step of recording test data while varying the recording power around the preset reference power; A second step of reproducing the recorded test data and detecting a jitter amount therefrom; And And a third step of confirming the change of the detected jitter amount and determining the optimum recording power therefrom by detecting or re-performing OPC. delete delete delete delete The method of claim 1, In the third step, the optimal recording power detection method of an optical disc apparatus, characterized in that the recording power of the minimum jitter amount is detected as the optimal recording power when the detected jitter amount gradually decreases and increases. The method of claim 1, The third step is to determine the OPC re-execution when the detected jitter amount continues to decrease or increase, the optimal recording power detection method of the optical disk device. The method of claim 7, wherein And if the detected jitter amount continues to decrease, further comprising a fourth step of performing the OPC operation again with the reference power increased by a predetermined value. The method of claim 7, wherein And if the detected jitter amount continues to increase, further comprising a fourth step of performing the OPC operation again in a state in which the reference power is decreased by a predetermined value. The method of claim 1, And the amount of change in the recording power is reduced when the OPC is determined to be re-executed.

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