CN1285071C - Laser power correcting method for stimulating real record - Google Patents
Laser power correcting method for stimulating real record Download PDFInfo
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- CN1285071C CN1285071C CN 03155331 CN03155331A CN1285071C CN 1285071 C CN1285071 C CN 1285071C CN 03155331 CN03155331 CN 03155331 CN 03155331 A CN03155331 A CN 03155331A CN 1285071 C CN1285071 C CN 1285071C
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- 238000004088 simulation Methods 0.000 claims description 18
- 230000003044 adaptive effect Effects 0.000 claims description 9
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Abstract
The present invention relates to a laser power correcting method for a stimulating real record. An optical disk system works within a duty ratio range which can be endured by an optical read/write head in a low power area and a high power area, and the actual laser power of the optical read/write head in the low power area and the high power area is measured. Therefore, the present invention can avoid a correcting error generated by predicting the laser power in the high power area by the low power range of safe continuous operation in a conventional method.
Description
Technical field
The present invention is relevant for a kind of laser power correction method, and particularly relevant for a kind of laser power correction method of simulating true record.
Background technology
In optical disk system, except the control circuit of control data access, usually come data on the access discs with an optical read/write head.Generally speaking, one deck reflective material is arranged in the recording layer of discs, when writing data, control circuit can be set the operand power parameter of optical read/write head, and by control one operating control signal, make optical read/write head send the laser power that writes intensity off and on, to act on above-mentioned reflective material off and on according to operating control signal.And when reading of data, then utilize the laser of detection of reflected, reduce the data value that is write.
Because when writing data, the laser power intensity that optical read/write head sent is higher, and according to the specification of optical read/write head, it is in order to luminous element-laser diode (Laser Diode, be called for short LD), and can't bear and send the laser power that writes intensity continuously.So work as in order to proofread and correct in the optical disk system, when operand power parameter that different circuit characteristics produces and laser power relation curve, because of but the safe laser power of continued operation is lower than the laser power that writes intensity, so correct operation is confined in the continuous working scope of the safety that specification limited of optical read/write head (power upper limit S that promptly can continuous working is following), cooperate mathematical methods such as so-called curve adaptive method (curve fit) and heterodyne again, remove to estimate extraneous operand power parameter of safe continuous working and laser power relation curve.
Please refer to shown in Figure 1ly, it is the relation curve synoptic diagram of conventional correct operation power parameter and laser power.Abscissa is represented the operand power parameter WDAC that optical disk system is set among the figure, and ordinate is the practical laser power P W for recording then.Among this figure, the laser power correction method that applied relation curve bearing calibration is continued operation, therefore correct operation just is confined in the continuous working scope of the safety below the S among the figure, utilize different operand power parameter WDAC in the continuous working scope of setting safety, and the practical laser performance number PW that records of record, with mathematical methods such as curve adaptive method and heterodynes, try to achieve its correction relationship curve A, reference during for practical operation and application again.
Significantly, this bearing calibration is the extraneous laser power of continuous working of the above safety of actual measurement S not, more talks how it is included in the consideration of curve when adaptive.The relation curve of supposing the operand power parameter of reality of this optical disk system and laser power shown in the B among the figure, and suppose this optical disk system required write intensity and be W the time, then when this optical disk system write data, will set its operand power parameter was D.Yet by the actual relationship curve B among the figure as can be known, D is in optical disk system for this operand power parameter, will obtain actual laser power W1, thereby produces the laser power error that writes intensity of W-W1, and then influence the quality of discs record.
Summary of the invention
Because above-mentioned shortcoming, the invention provides a kind of laser power correction method of simulating true record, but the method that its application simulation is recorded truly, come the extraneous laser power of continuous working of actual measurement safety, relation curve with operand power parameter and laser power in the true operation power bracket that obtains optical disk system, avoid to fill a part grasp real conditions, influence the record quality of discs because of the continued operation power bracket of only measuring safety.
For reaching above-mentioned and other purpose, the invention provides a kind of laser power correction method of simulating true record, be applicable to the laser power of proofreading and correct optical disk system.Laser power wherein is by the optical read/write head of optical disk system, responds an operating control signal and an operand power parameter produces.The method comprises the following steps: at first operating optical read/write head, realizes defocusing (defocus) operation to confirm optical read/write head; Set above-mentioned operating control signal and operand power parameter then, optical read/write head is worked in the working range (no matter also reach operation continuously or operate the working range that can not damage optical read head off and on) that can not damage optical read/write head; The sampling value of the laser power that the Laser Measurement read/write head produces; Relatively this operand power parameter obtains an error amount with this sampling value; And the laser power of proofreading and correct this optical read/write head according to this error amount.Certainly, defocusing operation is for fear of damageeing tested discs, and if can avoid tested discs to be damaged or to repair the damage of tested discs with other method, the present invention can omit this to defocus operation.
In the preferred embodiments of the present invention, the operating optical read/write head realize defocusing the step of operation to confirm optical read/write head, but the camera lens of operating optical read/write head is amesiality, or the camera lens vertical off setting focal position of operating optical read/write head is realized.
In addition, more can utilize the size of change aforesaid operations power parameter, measure the sampling value of the laser power that different operand power parameters responded then.Further use the sampling value of the laser power that the different operating power parameter measured responded again, ask for the relation curve of its operand power parameter and laser power with the curve adaptive method.Wherein the dutycycle of the operating control signal of Ying Yonging (duty cycle) is lower than the specification (as 50 percent) that optical read head production firm is formulated, and uses and avoids damaging optical read head because measuring the above power bracket of power upper limit S of continuous working.And during the sampling value of Laser Measurement power, the output of Laser Measurement power utilization one sample-and-hold circuit and the value that obtains.
The present invention provides a kind of laser power correction method of simulating true record in addition, is applicable to an optical disk system, and this optical disk system is according to an operand power parameter and an operating control signal, controls the laser power of the laser that optical read/write head produces.The method comprises the following steps: at first operating optical read/write head, so that optical read/write head defocuses operation; Set above-mentioned operand power parameter again; Control above-mentioned operating control signal then, make it to be equal to the operating control signal of optical read/write head when recording truly; Change laser again, take a sample and keep the signal that is obtained, keep signal to obtain a sampling; And keep signal according to sampling, obtain laser power; Relatively this laser power and this operand power parameter, and obtain an error amount; Proofread and correct this laser power according to this error amount; And change above-mentioned operand power parameter, to obtain different laser powers.
Similarly, also can use different operand power parameters and the laser power that is obtained, ask for the relation curve of operand power parameter and laser power with the curve adaptive method.
By in the above-mentioned explanation as can be known, use a kind of laser power correction method of simulating true record of the present invention, proofread and correct the required operand power parameter of laser power of optical disk system, the method of recording truly because of this method application simulation then, come the extraneous laser power of continuous working of actual measurement safety, with the real operand power parameter of acquisition optical disk system and the relation curve of laser power, so can avoid when using, influence the record quality of discs because only measuring the following error that is caused of the power upper limit S of continuous working.
Description of drawings
For above and other objects of the present invention, feature and advantage can be become apparent, hereinafter special with preferred embodiment, and conjunction with figs., be described in detail below:
Fig. 1 is the relation curve synoptic diagram of a kind of conventional correct operation power parameter of expression and laser power;
Fig. 2 is the control circuit synoptic diagram of a kind of optical disk system of expression;
Fig. 3 is a waveform synoptic diagram of representing to simulate according to the preferred embodiment of the invention the laser power correction method of true record;
Fig. 4 is the laser power correction method of simulation true record according to the preferred embodiment of the invention and the effect comparison diagram of routine techniques; And
Fig. 5 is the laser power correction method of simulation true record according to the preferred embodiment of the invention and another effect comparison diagram of routine techniques.
The accompanying drawing marking explanation:
200 control circuits
210 optical read/write heads
211 laser diode driver circuits
212 laser diodes
213 preposition photodiodes
220 digital/analog converters
230 comparers
240 integrators
250 sample-and-hold circuits
260 amplifiers
Embodiment
Please refer to shown in Figure 2ly, it is a kind of control circuit synoptic diagram of optical disk system.The operand power parameter WDAC of this control circuit 200 in order to set according to optical disk system controls the laser power PW that laser diode (LaserDiode is called for short LD) sends.That is to say, when optical disk system is desired on the access discs data, can utilize setting operation power parameter WDAC, with the size of the laser power PW that determines its operation, its principle of work will be described in detail as follows.
At first refer again to Fig. 2, show among the figure, this control circuit 200 comprises digital/analog converter 220, comparer 230, integrator 240, sample-and-hold circuit 250, amplifier 260, laser diode driver circuit 211, laser diode 212 and preposition photodiode (Front Photo Diode is called for short FPD) 213.Wherein, laser diode driver circuit 211, laser diode 212 and preposition photodiode 213 are arranged in the optical read/write head 210 of optical disk system.Digital/analog converter 220, comparer 230, integrator 240, sample-and-hold circuit 250 and amplifier 260 then are positioned among the CD control wafer (not illustrating).
When supposing that optical disk system desires to read data on the discs, will set its operand power parameter WDAC according to the size of required laser power PW.This operand power parameter WDAC utilizes digital/analog converter 220 to be converted to analogue value S1, and in the input comparator 230.Another input end of comparer 230 then receives the backfeed loop that preposition photodiode 213, sample-and-hold circuit 250 and amplifier 260 are constituted, the laser power PW that detection laser diode 212 sends and a detected value S2.Error E between this analogue value S1 and detected value S2 through the integration of integrator 240, obtains an integrated value SI, and this integrated value SI then imports laser diode driver circuit 211, sends laser with driving laser diode 212.The laser power PW that sends when laser diode 212, detection through preposition photodiode 213, and the detected value S2 that conversion obtained of the backfeed loop of sample-and-hold circuit 250 and amplifier 260 formations, when equaling the analogue value S1 of digital/analog converter 220 conversion operations power parameter WDAC, the output error E of comparer 230 will be 0, make integrator 240 be stable at its output integrated value SI.Thereby this closed-loop path control circuit laser power PW that laser diode 212 can be sent, be controlled in the respective value of the operand power parameter WDAC that optical disk system sets exactly.
Wherein, backfeed loop is with preposition photodiode 213, the laser power PW that comes detection laser diode 212 to send, its transformational relation are that reference voltage Vref is proportional to laser power PW with the level difference that detects output signal FPDO, for example PW/ (Vref-FPDO)=20mW/500mV.That is to say that heal by force as laser power PW, its level that detects output signal FPDO is lower.Sample-and-hold circuit 250 is then for for example when optical disk system works in the state that writes data, operating control signal OUTEN in the optical disk system meeting application drawing, utilize laser diode driver circuit 211, come controlling and driving laser diode 212 whether luminous, to carry out writing of data, the level that detects output signal FPDO this moment does not continue, so with sampling control signal FPDSH corresponding to operating control signal OUTEN, control sample-and-hold circuit 250, to obtain to detect the sampling value Vsh of output signal FPDO, the amplification through amplifier 260 becomes detected value S2 then.Certainly, for keeping the corresponding comparison of detected value S2 and analogue value S1, amplifier 260 can be negative gain amplifier.
Below with reference to the control circuit 200 of Fig. 2 and the waveform synoptic diagram of Fig. 3, the laser power correction method that simulation of the present invention is recorded truly is described.Because laser power correction method of the present invention is at timing,, be confined in the continuous working scope of the safety that specification limited of optical read/write head 210 no longer with exercisable laser power PW.Therefore, use method of the present invention to come calibration of laser power P W before, as the laser power PW of its operation, when being positioned at the high power district, burn out discs on it for fear of laser, can first operating optical read/write head 210, realize defocusing (defocus) operation to confirm optical read/write head 210.This operation can operating optical read/write head 210 camera lens (not illustrating) amesiality, or the camera lens of operating optical read/write head 210 (not illustrating) vertical off setting focal position is realized.Certainly, as use special test pieces, or when record the time is repaired section that test uses or logging program again and can have been overcome this problem, then need not operating optical read/write head 210 defocus operation.
After confirming that optical read/write head 210 realizes defocusing (defocus) operation, get final product setting operation control signal OUTEN and operand power parameter WDAC, optical read/write head 210 is worked in the working range that can not damage optical read/write head 210.That is to say, as the pairing laser power PW of operand power parameter WDAC that sets, be positioned at the continuous working scope of the safety that specification limited of optical read/write head 210 when outer, the dutycycle (duty cycle) of necessary setting operation control signal OUTEN, make it be lower than the duty cycle range that optical read/write head 210 can bear in the high power district, this scope for example is to be not more than 50 percent scope, shown in the waveform of Fig. 3 OUTEN.
Then, the sampling value Vsh of the laser power PW of Laser Measurement read/write head 210 generations.Vsh is in Fig. 2 for this sampling value, with preposition photodiode 213, the laser power PW that comes detection laser diode 212 to send, produce detection output signal FPDO as Fig. 3, again through the sampling of sampling control signal FPDSH control sample-and-hold circuit 250 with keep, to obtain the sampling value Vsh of stable laser power PW.Certainly, as is known to the person skilled in the art,, equally also can obtain the laser power PW of respective operations power parameter WDAC as the output detected value S2 of amplifier 260 in the survey sheet 2.
In view of the above, utilize the size of change aforesaid operations power parameter WDAC, measure the sampling value Vsh of the laser power PW that different operand power parameter WDAC responded then.The sampling value Vsh of the laser power PW that further again application measurement different operating power parameter WDAC is responded, ask for the relation curve of its operand power parameter WDAC and laser power PW with curve adaptive method (curve fit), to obtain as the actual relationship curve B among Fig. 1.Then use this actual relationship curve B, operate this optical disk system, just can avoid laser power error as the W-W1 among Fig. 1.
Please referring to shown in Figure 4, it is the effect comparison diagram of simulating the laser power correction method of recording truly according to the preferred embodiment of the invention.Curve C among the figure is the operand power parameter of reality of optical disk system and the relation curve (supposing that herein it is a linear relationship) of laser power, curve A is the correction relationship curve that bearing calibration obtained of the continuous working scope of the following safety of the conventional correction of application S, the correction relationship curve that curve B is then obtained for the laser power correction method of using simulation true record according to the preferred embodiment of the invention.By among the figure as can be known because the laser power correction method recorded truly of simulation according to the preferred embodiment of the invention can be proofreaied and correct the above scope of safe continuous working scope S simultaneously, therefore, the correction relationship curve of acquisition will more be close to actual relation curve C.
Please referring to shown in Figure 5, it is another effect comparison diagram of simulating the laser power correction method of recording truly according to the preferred embodiment of the invention.Curve C among the figure is the operand power parameter of reality of optical disk system and the relation curve (supposing that herein it is a nonlinear relationship) of laser power, curve A is the correction relationship curve that bearing calibration obtained of the continuous working scope of the following safety of the conventional correction of application S, the correction relationship curve that curve B is then obtained for the laser power correction method of using simulation true record according to the preferred embodiment of the invention.By among the figure as can be known, because conventional method only can be proofreaied and correct the continuous working scope of the following safety of S, so that the scope substantial deviation actual relationship curve C more than S, and the laser power correction method recorded truly of simulation according to the preferred embodiment of the invention, then can proofread and correct the above scope of safe continuous working scope S simultaneously, and optionally adopt the adaptive correction relationship curve of asking for of segmentation, therefore, the correction relationship curve of acquisition can more be close to actual relation curve C.
In sum as can be known, a kind of laser power correction method of simulating true record of the present invention has following advantage at least:
1. the method for recording truly because of this method application simulation, come the extraneous laser power of continuous working of actual measurement safety, with the real operand power parameter of acquisition optical disk system and the relation curve of laser power, so when using, can avoid because of the sampling scope is not sufficiently complete or truly closes is factor such as nonlinearities change, and influences the record quality of discs.
2. because of in timing, that confirms optical read/write head defocuses operation (or operation of other equivalence) in advance, so can avoid burning out discs.
3. because of the dutycycle of setting operation control signal OUTEN, make it be lower than the duty cycle range that optical read/write head can bear in the high power district, so can realize the gamut correction work safely.
Though the present invention with preferred embodiment openly as above; right its is not in order to limit the present invention; any those skilled in the art; under the situation that does not break away from the spirit and scope of the present invention; can carry out various changes and modification, so protection scope of the present invention is as the criterion with the claim restricted portion that is proposed.
Claims (9)
1. laser power correction method of simulating true record, be used to proofread and correct the laser power of an optical disk system, this laser power is by an optical read/write head of this optical disk system, responds an operating control signal and an operand power parameter produces, and this method comprises the following steps:
Set this operating control signal and this operand power parameter, so that this optical read/write head is worked in the working range that can not damage this optical read/write head, wherein the dutycycle of this operating control signal be not more than optical read head production firm given specification;
Measure a sampling value of this laser power of this laser and/write head generation;
Relatively this operand power parameter obtains an error amount with this sampling value; And
Proofread and correct the laser power of this optical read/write head according to this error amount.
2. the laser power correction method that simulation as claimed in claim 1 is recorded truly wherein also comprises the following steps:
This optical read/write head of operation is realized defocusing operation to confirm this optical read/write head earlier, measures this sampling value again.
3. the laser power correction method that simulation as claimed in claim 2 is recorded truly is wherein operated this optical read/write head to confirm that the step that this optical read/write head realization defocuses operation is the amesiality or vertical off setting focal position of camera lens of this optical read/write head of operation.
4. the laser power correction method that simulation as claimed in claim 1 is recorded truly, wherein variable this operand power parameter size is to measure this sampling value of this laser power that different these operand power parameters are reacted.
5. the laser power correction method that simulation as claimed in claim 4 is recorded truly, wherein further use above-mentioned a plurality of sampling values of above-mentioned a plurality of laser powers of measuring above-mentioned a plurality of operand power parameters, ask for a relation curve of above-mentioned a plurality of operand power parameters and above-mentioned a plurality of laser powers with the curve adaptive method.
6. laser power correction method of simulating true record, be applicable to an optical disk system, this optical disk system is according to an operand power parameter and an operating control signal, controls the laser power of the laser that an optical read/write head produced, and this method comprises the following steps:
Set this operand power parameter;
Control this operating control signal, make to be equal to this optical read/write head this operating control signal when recording truly, and the dutycycle of this operating control signal be not more than this optical read head production firm given specification;
Change this laser, take a sample and keep the signal that is obtained, keep signal to obtain a sampling;
Keep signal according to this sampling, obtain this laser power;
Relatively this laser power and this operand power parameter, and obtain an error amount;
Proofread and correct this laser power according to this error amount; And
Change this operand power parameter, to obtain this different laser powers.
7. the laser power correction method that simulation as claimed in claim 6 is recorded truly also comprises the following steps:
Use different operand power parameters and the laser power that is obtained, ask for a relation curve of this operand power parameter and this laser power with the curve adaptive method.
8. the laser power correction method that simulation as claimed in claim 6 is recorded truly wherein also comprises the following steps:
This optical read/write head of operation is realized defocusing operation to confirm this optical read/write head earlier, changes this laser again, keeps signal to obtain this sampling.
9. the laser power correction method that simulation as claimed in claim 8 is recorded truly is wherein operated this optical read/write head so that this optical R/W realizes defocusing the camera lens amesiality or vertical off setting focal position of the step of operation for this optical read/write head of operation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03155331 CN1285071C (en) | 2003-08-27 | 2003-08-27 | Laser power correcting method for stimulating real record |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03155331 CN1285071C (en) | 2003-08-27 | 2003-08-27 | Laser power correcting method for stimulating real record |
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| CN1489139A CN1489139A (en) | 2004-04-14 |
| CN1285071C true CN1285071C (en) | 2006-11-15 |
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| CN 03155331 Expired - Fee Related CN1285071C (en) | 2003-08-27 | 2003-08-27 | Laser power correcting method for stimulating real record |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1302475C (en) * | 2004-04-29 | 2007-02-28 | 建兴电子科技股份有限公司 | Laser Power Control Method Applied to CD Recorder |
| US7420580B2 (en) * | 2004-10-29 | 2008-09-02 | Hewlett-Packard Development Company, L.P. | Laser power calibration in an optical disc drive |
| CN100380459C (en) * | 2005-05-31 | 2008-04-09 | 威盛电子股份有限公司 | Best Power Correction Method and Optical Drive |
| CN101626134B (en) * | 2008-07-11 | 2012-02-08 | 武汉奇致激光技术有限公司 | System and control method for determining laser energy correction value of laser |
| JP7170583B2 (en) * | 2019-05-17 | 2022-11-14 | 株式会社東芝 | Magnetic recording device and its magnetic head control method |
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