CN1314009C - Quality detection method of high multiplier speed universal optical disk based on focusing error - Google Patents

Abstract

The present invention relates to a quality testing method of high speed and high density disks based on focusing error, which belongs to the technical field of the optical storage. Firstly, the rotary speed of the disk to be tested is supposed to be n-tupling speed, a laser reflecting flare on an optical disk is divided into four facular zones, and the arithmetic operation for four voltage signals corresponding to each facular zone are carried out to an obtain focusing error signal; the expectant wow and flutter value of the quality of the disk to be tested is set, and the focusing offset value of a standard disk corresponding to the wow and flutter value is tested; the focusing offset value of the standard disk is set into a threshold of a peak to peak value of the focusing signal of the disk to be tested, and the focusing error signal of the disk to be tested is compared with the threshold of a peak to peak value; when the focusing error signal is positioned in the threshold, the quality of the disk to be tested is qualified; when the focusing error signal is positioned out of the threshold, the quality of the disk is not qualified. As the method of the present invention has less critical parameters for the disk to be tested, the testing speed is high, the present invention is suitable for testing the quality of the disk on line and in mass, and the testing efficiency of the disk is improved.

Description

Quality determining method based on the high multiplier speed universal optical disk of focusing error

Technical field

The present invention relates to a kind of quality determining method of the high multiplier speed universal optical disk based on focusing error, relate in particular to the high power speed DVD disc quality determining method of digital versatile disc (hereinafter to be referred as DVD), belong to field of optical storage technology.

Background technology

In optical disc driving arrangements such as present DVD-player and DVD-ROM, the record of optical disc information and extraction, realize by disc drive unit, it will become the sub-micron hot spot from the light beam of laser instrument, and focus on and the channel servocontrol according to the optical signalling from disc reflection, overcome the various errors in the CD rotation is read.Although disc drive unit has adopted servo tracking system to read various errors in the process with correction, but by the caused error of disc itself, as eccentric, face shakes and reflectivity etc., can and read the RF signal to CD drive and produce various deleterious effects, produce noise as the eccentric excessive driver that can make of disc, reflectivity is crossed the young pathbreaker can not normal read go out disc information etc.

Therefore, in DVD disc production run, the purpose of rom test is for CD provides the disc quality information, rejects defective disc, and the foundation that disc copied line and production environment parameter are adjusted is provided.

At present, in the industrial processes of DVD CD, traditional CD electrical quantity quality evaluating method often is core with the standard drive, is judged the quality of disc then by the signal evaluation module.The conventional optical disc electric parameter detecting method adopts the evaluated off-line mode usually, promptly carries out parameter evaluation usually after disc is finished, and estimates one disc and need the long period, and rotational speed is lower during the disc test, is equivalent to 1～4 times of speed of DVD disc.

Traditional CD parameter detection method detects and can satisfy the demand substantially for CD quality.Yet because traditional CD parameter evaluation device is long detection time, there is significant limitation when being applied to the online quality management of CD, can not real time reaction optical disc production mass change.And disc rotation speed was lower when traditional CD electrical quantity was estimated, and can not reflect the read output signal quality of DVD disc under high power speed situation, was used for detecting high power speed DVD disc quality and had significant limitation.

Goal of the invention

The objective of the invention is to propose a kind of quality determining method of the high multiplier speed universal optical disk based on focusing error, utilize the variation of focusing error under the high power speed that the disc quality is carried out detection of dynamic, and judge the disc quality of high power speed DVD.

The quality determining method based on the high power speed high-density disk of focusing error that the present invention proposes comprises following each step:

(1) rotating speed of establishing disc to be measured is a doubly speed of n, makes the detection system initialization, focuses on the CD reflection layer with laser beam, obtains the primary reflection hot spot after the CD reflection;

(2) above-mentioned flare is divided into four facular areas, the light intensity of each facular area is carried out opto-electronic conversion, obtain four voltages, represent the light intensity of four facular areas respectively;

(3) voltage signal of four facular area light intensity of above-mentioned representative is carried out arithmetic and obtain focus error signal;

(4) set the desired quiver value of disc quality to be measured, and the focus offset of mensuration and the pairing standard disc of this quiver value;

(5) focus offset of above-mentioned standard disc is set at the peak-to-peak value threshold values of disc focus signal to be measured, the focus error signal and the peak-to-peak value threshold values of above-mentioned disc to be measured are compared, if focus error signal is positioned at threshold values, disc then to be measured is up-to-standard, if focus error signal is positioned at outside the threshold values, disc then to be measured is off quality.

The quality determining method based on the high multiplier speed universal optical disk of focusing error that the present invention proposes, its advantage is few to the evaluating of disc to be measured, so detection speed is fast, is suitable for the quality of online, in enormous quantities fast detecting disc, improves the disc detection efficiency.

Description of drawings

Fig. 1 utilizes the inventive method to detect the schematic diagram of device of disc quality.

Among Fig. 1, the 1st, disc, the 2nd, object lens, the 3rd, photodetector, the 4th, spindle motor.

Specific implementation method

The quality determining method that the present invention proposes based on the high multiplier speed universal optical disk of focusing error, at first, the rotating speed of establishing disc to be measured is a doubly speed of n, makes the detection system initialization, focus on the CD reflection layer with laser beam, obtain the primary reflection hot spot after the CD reflection; Above-mentioned flare is divided into four facular areas, the light intensity of each facular area is carried out opto-electronic conversion, obtain four voltages, represent the light intensity of four facular areas respectively; The voltage signal of four facular area light intensity of above-mentioned representative is carried out arithmetic obtain focus error signal; Set the desired quiver value of disc quality to be measured, and the focus offset of mensuration and the pairing standard disc of this quiver value; The focus offset of above-mentioned standard disc is set at the peak-to-peak value threshold values of disc focus signal to be measured, the focus error signal and the peak-to-peak value threshold values of above-mentioned disc to be measured are compared, if focus error signal is positioned at threshold values, disc then to be measured is up-to-standard, if focus error signal is positioned at outside the threshold values, disc then to be measured is off quality.

The quality determining method based on the high multiplier speed universal optical disk of focusing error that the present invention proposes, the principle of its foundation illustrates in greater detail content of the present invention as shown in Figure 1 below with reference to accompanying drawings.In Fig. 1, disc 1 is clamped on the spindle motor 4.Object lens 2 can make the photoimaging of disc reflection on four picture limit detectors 3, and can move along tracking and focus direction by the twin shaft torquer.So this detection method comprises following each step:

The rotating speed of setting disc is a doubly speed (n 〉=4) of n, and the linear velocity of one times of speed of CD is 3.49m/s.

The focus servo closed loop, radial servo closed loop, and Adjustment System, eliminate photoelectricity four picture limit detectors radially and tangential deviation, can obtain the primary reflection hot spot from the CD reflection.

The light intensity of each facular area is carried out opto-electronic conversion, obtain four voltage: Ua, Ub, Uc, Ud, represent the light intensity of four facular areas respectively.Above-mentioned four voltage signals are carried out arithmetic obtain focus error signal Ua+Uc-Ub-Ud.

The wow and flutter Jitter value that the assignment disk tablet quality is desired is measured the pairing focusing biasing of this Jitter value Defocus value and is fel.The peak-to-peak value threshold values of setting focus signal be ± fel, if focus error signal is positioned at threshold values, then disc is up-to-standard, is positioned at outside the threshold values as if focus error signal, and then disc is off quality.

Claims (1)

1, a kind of quality determining method of the high power speed high-density disk based on focusing error is characterized in that this method comprises following each step:

(1) rotating speed of establishing disc to be measured is a doubly speed of n, makes the detection system initialization, focuses on the CD reflection layer with laser beam, obtains the primary reflection hot spot after the CD reflection, wherein n 〉=4;

(2) above-mentioned flare is divided into four facular areas, the light intensity of each facular area is carried out opto-electronic conversion, obtain four voltages, represent the light intensity of four facular areas respectively;

(3) voltage signal with four facular area light intensity of above-mentioned representative carries out the Ua+Uc-Ub-Ud arithmetic, obtains focus error signal;

(4) set the desired quiver value of disc quality to be measured, and the focus offset of mensuration and the pairing standard disc of this quiver value;

(5) focus offset of above-mentioned standard disc is set at the peak-to-peak value threshold values of disc focus signal to be measured, the focus error signal and the peak-to-peak value threshold values of above-mentioned disc to be measured are compared, if focus error signal is positioned at threshold values, disc then to be measured is up-to-standard, if focus error signal is positioned at outside the threshold values, disc then to be measured is off quality.

Images