CN100392732C - Method and apparatus for adjusting focusing bias of optical disk drive unit - Google Patents
Method and apparatus for adjusting focusing bias of optical disk drive unit Download PDFInfo
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- CN100392732C CN100392732C CNB2005100220676A CN200510022067A CN100392732C CN 100392732 C CN100392732 C CN 100392732C CN B2005100220676 A CNB2005100220676 A CN B2005100220676A CN 200510022067 A CN200510022067 A CN 200510022067A CN 100392732 C CN100392732 C CN 100392732C
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Abstract
The present invention relates to an optical method and an apparatus for adjusting focusing bias of optical disk drive units. The method adopts the following steps: drive voltage is exerted on a focusing torquer in an optical disk drive unit to make a distance between an objective lens in the optical disk drive unit and an optical disk correspondingly joggle by using a standard distance as the center; a laser light spot emitted on the optical disk is reflected on an optical head detector; the optical head detector is used for carrying out photoelectric conversion to the received light spot for obtaining a focusing error signal curve; the corresponding drive voltage value of extreme value occurrence time is obtained according to the extreme value occurrence time in the focusing error signal curve, and the drive voltage value is the voltage value of extreme value occurrence; the standard distance is adjusted for making the voltage value of extreme value occurrence in a setting limit for obtaining a result adjusting distance. The present invention has the advantages of high adjusting accuracy, low cost, strong practicability and good reliability.
Description
Technical field
The present invention relates to optics, relate in particular to a kind of focusing biasing method of adjustment and device of disk drive unit.
Background technology
In optical storage system, the major function of disk drive unit is driving disk rotation, produce the laser facula that reads optical disc information, will carry out opto-electronic conversion and produce photo detector signal, move and read hot spot and arrive functions such as the radial position of appointment and axial location through the laser facula that reads after the disc reflection.
In the performance parameter of small movement, the distance between object lens and the CD is the important parameter that disk drive unit (small movement) is produced and detected, small movement is read radiofrequency signal produce bigger influence, and be to influence the key factor that optical disk reading goes out quality.This distance is determined by the small movement design of Optical System, is imaged on the reflection horizon of disc to guarantee the laser beam that laser instrument sends.
In the prior art, the modal problem of focus servo is to focus on biasing.When there is height tolerance in spindle motor, or the rail height that optical head is installed is when existing deviation, can cause object lens and CD apart from the off-design position, promptly disk drive unit (small movement) exists bigger focusing to setover.Focusing on biasing makes the focusing torquer of disk drive unit (small movement) have DC voltage all the time in the process of read-write disc, may exceed the scope that focus servosystem bears, cause and focus on torquer to depart from physical slot (torquer is the position during making alive not) excessive and can't normally focus on, reduce the serviceable life that focuses on torquer, even produce damage focusing on torquer.
At present, adjust for the focusing of disk drive unit biasing, adopt static adjustment mode to guarantee distance between object lens and the CD usually, its groundwork process is as follows:
With the CD fixed clamp on the disk holder on the spindle motor, disk holder is fixed on the unit pedestal of small movement, the optical system of disk drive unit and object lens also are positioned on the corresponding optical system support, and optical mount is fixed on the substrate of small movement by guide rail slidably.
In existing adjustment mode, distance between object lens and the CD is the distance by disk holder and unit pedestal, and the distance assurance of optical mount and unit pedestal, usually by Machine Design, processing and assembly technology guarantee its precision, but because optical head travelling carriage error, unit pedestal distortion (the plastics pedestal more so), the influence of factors such as gear train (rack-and-pinion or thread screw) alignment error, this mode can not guarantee the setting operating distance of object lens and CD, the adjustment precision is low, and higher spare and accessory parts machining precision makes that also cost is higher.
Summary of the invention
The object of the present invention is to provide a kind of focusing biasing method of adjustment and device of adjusting the low disk drive unit of precision height and cost, to overcome defective of the prior art.
The focusing biasing method of adjustment of the disk drive unit among the present invention adopts following steps:
A, the focusing torquer in disk drive unit apply driving voltage, make object lens in the disk drive unit be that the center is relative with distance between the CD with a benchmark spacing and shake;
B, penetrate at the laser facula on the CD and reflect on the optical head detector;
C, optical head detector carry out opto-electronic conversion to received hot spot, and computing module receives the electric signal after optical head detector opto-electronic conversion, calculate the focus error signal amount, are sent to memory module, obtain the focus error signal curve;
D, comparison module are obtained the corresponding driving voltage value of described extreme value time of origin according to the extreme value time of origin in the described focus error signal curve, and this driving voltage value is an extreme value generation magnitude of voltage;
E, make described extreme value generation magnitude of voltage be within the tolerance limit of setting, obtain and adjust as a result spacing and export display module to by adjusting described benchmark spacing.
In the described steps A, the focusing torquer in described disk drive unit applies driving voltage, drives the focusing torquer and makes object lens make periodic axially reciprocating.
In the described steps A, described driving voltage is a magnitude of voltage sawtooth voltage in respect of time, and described sawtooth wave is with the fluctuation of 0V magnitude of voltage symmetry.
In the described steps A, the frequency of described driving voltage is 0.5Hz to 6Hz.
Described step C comprises the steps:
C1, described optical head detector adopt four picture limit detectors, and this detector will be in the facular area light intensity of each picture limit and carry out opto-electronic conversion respectively;
C2, detect the corresponding voltage of each picture limit respectively;
C3, computing module calculate the focus error signal amount according to the corresponding voltage of described each picture limit, and described focus error signal amount is pressed summation and even numbers to look like to ration the power supply for odd number looks like to ration the power supply and pressed the poor of summation;
C4, memory module be according to described focus error signal amount and corresponding time relation, produces the focus error signal curve of focus error signal amount and corresponding time formation.
Among the described step D, described extreme value is the maximal value or the minimum value of focus error signal amount.
Described extreme value is presented as the absolute value of focus error signal amount more than or equal to a threshold values of setting, or the mean value that is associated with described threshold values.
Described step e comprises the steps:
E1, setting one focus on biasing tolerance limit [e
0, e
0], wherein, e
0For on the occasion of;
E2, according to focusing on torquer sensitivity K, calculating voltage value tolerance limit, that is, [e
0/ K, e
0/ K];
E3, according to described extreme value generation magnitude of voltage, carry out following operation:
E31, if this extreme value generation magnitude of voltage is positioned among the magnitude of voltage tolerance limit, get described benchmark spacing for adjusting as a result spacing and exporting display module to;
E32, if this extreme value generation magnitude of voltage is positioned at outside the magnitude of voltage tolerance limit, adjust described benchmark spacing, to benchmark spacing renewal, repeating step A is to step e 2 with adjusted spacing.
The focusing offset adjusting apparatus of this disk drive unit, comprise disk drive unit, Amici prism, optical head detector and center processing unit, described disk drive unit comprises disk holder, unit pedestal, object lens, focusing torquer and laser instrument, described disk holder is installed on the unit pedestal, and described focusing torquer drives object lens and moves, and described Amici prism places the light path of laser instrument and object lens, receive the reflected light of CD, and it is reflexed to the optical head detector; Described center processing unit receives the electric signal after optical head detector opto-electronic conversion, carries out corresponding calculating, processing, the output result;
Described center processing unit comprises computing module, memory module, comparison module and display module, wherein,
Described computing module receives the electric signal of optical head detector output, calculates the focus error signal amount, and computing information is sent to memory module;
Described memory module receives, preserves the periodic voltage data that put on the focusing torquer, the computing information of computing module output;
Described comparison module calls the information in the memory module, obtains extreme value generation magnitude of voltage, and described extreme value generation magnitude of voltage and magnitude of voltage tolerance limit are compared, and comparative result exports display module to.
Described optical head detector is four picture limit detectors.
Also be provided with quarter wave plate in the light path of described laser instrument and object lens.
Also be provided with collimation lens in the light path of described laser instrument and object lens.
Beneficial effect of the present invention is: in the present invention, be in dynamic reflected laser light spot by the optical head detector and carry out opto-electronic conversion, obtain the focus error signal curve, obtain extreme value generation magnitude of voltage according to the extreme value time of origin in the focus error signal curve, according to this extreme value generation magnitude of voltage the distance between object lens and the CD is optimized, like this, the Machine Design of spare and accessory parts, processing and assembly technology error are for the influence of the actual range between object lens and the CD, can compensate dynamically by the present invention, proofread and correct, this also just means with respect to prior art, the present invention is for the Machine Design of spare and accessory parts, processing and assembly technology accuracy requirement are low, improved the suitability of product assembling, reduced cost, and, in the present invention, this focusing biasing adjustment precision only depends on the tolerance limit that sets, guaranteed adjustment precision of the present invention from principle, for the dependent reduction of mechanical technology precision, but expected performance and functional reliability that precision is adjusted have been improved, reduced the influence that the factor of can not surveying is adjusted precision, make the present invention have very strong practicality and reliability, and, method and apparatus among the present invention can be inserted in the real-time working system of disk drive unit, like this, after disk drive unit or final assembly, also can detect optical head and whether be positioned at suitable error range moving radially scope inner focusing biasing, and do real-time focusing biasing and adjust.
Description of drawings
Fig. 1 is a system architecture synoptic diagram of the present invention;
Fig. 2 is a center processing unit structural representation of the present invention;
Fig. 3 is the synoptic diagram of contrasting of focus error signal curve among the present invention and driving voltage;
Fig. 4 is a basic controlling flow process synoptic diagram of the present invention;
Fig. 5 is the concrete control flow synoptic diagram of the present invention;
Fig. 6 is S shape pulse-spreading synoptic diagram in the focus error signal curve among the present invention.
Embodiment
With embodiment the present invention is described in further detail with reference to the accompanying drawings below:
According to Fig. 1 and Fig. 2, the present invention includes disk drive unit, disk drive unit comprises disk holder 11, unit pedestal 12, object lens 13, focuses on torquer 14, laser instrument 15, Amici prism 4, optical head detector 5 and center processing unit 6.As shown in Figure 1, disk holder 11 is installed on the unit pedestal 12, lays CD 2 on the disk holder 11, focuses on torquer 14 driving object lens 13 and moves.
As shown in Figure 1, Amici prism 4 places the light path of laser instrument 15 and object lens 13, receives the reflected light of CD, and it is reflexed to optical head detector 5, and in the present invention, optical head detector 5 is four picture limit detectors.
As shown in Figure 1, the electric signal that center processing unit 6 receives after optical head detector 5 opto-electronic conversion carries out corresponding calculating, processing, the output result, as shown in Figure 2, center processing unit 6 comprises computing module 61, memory module 62, comparison module 63 and display module 64.
As shown in Figure 2, computing module 61 receives the electric signal of optical head detector 5 outputs, calculates the focus error signal amount, and computing information is sent to memory module 62.
As shown in Figure 2, memory module 62 receives, preserves the driving voltage data that put on focusing torquer 14, the computing information of computing module 61 outputs.
As shown in Figure 2, the information in 63 pairs of memory modules 62 of comparison module is called, and obtains extreme value generation magnitude of voltage, and described extreme value generation magnitude of voltage and magnitude of voltage tolerance limit are compared, and comparative result exports display module 64 to.
As shown in Figure 1, also be provided with quarter wave plate 7 and collimation lens 3 in the light path of laser instrument 15 and object lens 13.
As shown in Figure 1 and Figure 4, basic controlling flow process of the present invention is as follows:
1) apply driving voltage Uact (t) to focusing on torquer 14, make object lens 13 in the disk drive unit be that the center is relative with distance between the CD 2 with a benchmark spacing d and shake, focusing torquer 14 makes object lens 13 make periodic axially reciprocating.
2) laser instrument 15 emitted laser hot spots focus on the CD 2, and CD 2 reflexes to Amici prism 4 with laser facula, is reflected on the optical head detector 5 again.
3) 5 pairs of received laser faculas of optical head detector carry out opto-electronic conversion, and the electric signal that center processing unit 6 receives after optical head detector 5 opto-electronic conversion carries out corresponding calculating, obtains focus error signal curve FE (t).
4) as shown in Figure 3, center processing unit 6 is according to focus error signal curve FE (t) and driving voltage Uact (t), obtain the extreme value time of origin of focus error signal curve FE (t), obtain corresponding driving voltage Uact (t) value, i.e. extreme value generation magnitude of voltage according to this extreme value time of origin;
5) make extreme value generation magnitude of voltage be within the tolerance limit of setting by adjusting benchmark spacing d, obtain and adjust spacing as a result.
As Fig. 1, Fig. 2 and shown in Figure 5, below just the concrete control flow of the present invention describe in detail:
1, applies driving voltage Uact (t) to focusing on torquer 14, making object lens 13 in the disk drive unit be that the center is relative with distance between the CD 2 with a benchmark spacing d shakes, focusing on torquer 14 makes object lens 13 make periodic axially reciprocating, as shown in Figure 3, this driving voltage Uact (t) is a magnitude of voltage sawtooth voltage in respect of time, and described sawtooth wave is with the fluctuation of 0V magnitude of voltage symmetry, in the present invention, the frequency of driving voltage Uact (t) is good with 0.5Hz to 6Hz, among this embodiment, the frequency of driving voltage Uact (t) is 5Hz.
2, laser instrument 15 emitted laser hot spots focus on the CD 2, and CD 2 reflexes to Amici prism 4 with laser facula, are reflected on the optical head detector 5 again, and its concrete light path is as follows:
3, optical head detector 5 of the present invention is four picture limit detectors, and the facular area light intensity that this four pictures limit detector will be in each picture limit is carried out opto-electronic conversion respectively.
4, four pictures limit detectors to detect the corresponding voltage of each picture limit respectively, and the voltage of limitting for first, second, third, fourth picture is respectively U
a, U
b, U
cAnd U
d
5, four picture limit detectors are sent to computing module 61 in the center processing unit 6 with detected electric signal, and computing module 61 is according to U
a, U
b, U
cAnd U
dCalculate focus error signal FE (t) amount, focus error signal FE (t) amount is pressed summation and even numbers to look like to ration the power supply for odd number looks like to ration the power supply and is pressed the poor of summation, therefore, and FE (t)=(U
a+ U
c)-(U
b+ U
d), in this computing module 61, can adopt two totalizers, respectively to one, three voltage sums as limit, and the voltage sum of two, four picture limits is carried out computing, the output of two totalizers inserts the input end of a subtracter more respectively, and output focus error signal FE (t) measured after subtracter was finished subtraction.
6, computing module 61 is sent to memory module 62 with operation result, as shown in Figure 3, according to focus error signal FE (t) amount and corresponding time relation, produces focus error signal FE (t) curve of focus error signal amount and corresponding time formation; Simultaneously, memory module 62 receives, preserves driving voltage Uact (t) data that put on focusing torquer 14.
7, data, the information in 63 pairs of memory modules 62 of comparison module is called, according to the extreme value time of origin in focus error signal FE (t) curve, be the maximal value or the minimum value time of origin of focus error signal FE (t) amount, obtain corresponding driving voltage Uact (t) value of this extreme value time of origin, this driving voltage Uact (t) value is extreme value generation magnitude of voltage, as shown in Figure 3, be the extreme value time of origin at a time point ts, corresponding Uact (ts) value is extreme value generation magnitude of voltage.
In the present invention, extreme value can be presented as that the absolute value of focus error signal amount is more than or equal to a threshold values of setting, or the mean value that is associated with described threshold values, for example, can set a threshold values earlier, when the absolute value of focus error signal amount equaled threshold values, the corresponding time of origin of this focus error signal FE (t) amount was the extreme value time of origin.
And for example, absolute value is more than or equal to the mean value of the focus error signal amount of setting threshold values in the spike among the calculating focus error signal FE (t), this mean value can be arithmetic mean, it also can be root mean square average, or adopt the mean value of other computing method, be the extreme value time of origin according to the pairing time of origin of the mean value that calculates.
In the present invention, the pulse in the focus error signal curve is a S shape curve, as shown in Figure 6, in actual applications, the extreme value time of origin in fact can get among the MNRPQ more arbitrarily.As generalized case, desirable R point, the magnitude of voltage that this R is ordered equals the mean value of MG or QH section; Because there is noise in focus error signal FE (t), therefore, often get in M1NM2 section or the Q1PQ2 section any point and try to achieve the extreme value time of origin, promptly require to have certain threshold values.
In a word, the extreme value time of origin can adopt above-mentioned method to obtain according to actual needs.
8, set one and focus on biasing tolerance limit [e
0, e
0], wherein, e
0For on the occasion of, promptly focusing on amount of bias can be more than or equal to-e
0And be less than or equal to e
0
9, according to focusing on torquer sensitivity K, calculating voltage value tolerance limit, i.e. [e
0/ K, e
0/ K], magnitude of voltage can be more than or equal to-e
0/ K and be less than or equal to e
0/ K.
10, according to above-mentioned extreme value generation magnitude of voltage, carry out following operation:
101, if this extreme value generation magnitude of voltage is positioned among the magnitude of voltage tolerance limit, get benchmark spacing d for adjusting spacing as a result, and spacing and relevant adjustment information thereof as a result will be adjusted, for example adjust successful information, corresponding focus error signal FE (t) amount, driving voltage Uact (t) value etc., export display module 64 to.
102, if this extreme value generation magnitude of voltage is positioned at outside the magnitude of voltage tolerance limit, adjust the distance between object lens 13 and the CD 2, with adjusted spacing benchmark spacing d is upgraded, repeat above-mentioned steps 1 to step 9, adjust spacing as a result until obtaining.
Method and apparatus among the present invention can be inserted in the real-time working system of disk drive unit, like this, after disk drive unit or final assembly, also can detect optical head and whether be positioned at suitable error range moving radially scope inner focusing biasing, and do real-time focusing biasing and adjust.
Claims (12)
1. the focusing of disk drive unit biasing method of adjustment, it is characterized in that: it adopts following steps:
A, the focusing torquer in disk drive unit apply driving voltage, make object lens in the disk drive unit be that the center is relative with distance between the CD with a benchmark spacing and shake;
B, penetrate at the laser facula on the CD and reflect on the optical head detector;
C, optical head detector carry out opto-electronic conversion to received hot spot, and computing module receives the electric signal after optical head detector opto-electronic conversion, calculate the focus error signal amount, are sent to memory module, obtain the focus error signal curve;
D, comparison module are obtained the corresponding driving voltage value of described extreme value time of origin according to the extreme value time of origin in the described focus error signal curve, and this driving voltage value is an extreme value generation magnitude of voltage;
E, make described extreme value generation magnitude of voltage be within the tolerance limit of setting, obtain and adjust as a result spacing and export display module to by adjusting described benchmark spacing.
2. the focusing of disk drive unit according to claim 1 biasing method of adjustment, it is characterized in that: in the described steps A, focusing torquer in described disk drive unit applies driving voltage, drives focusing cutter square device and makes object lens make periodic axially reciprocating.
3. the focusing of disk drive unit according to claim 2 biasing method of adjustment, it is characterized in that: in the described steps A, described driving voltage is a magnitude of voltage sawtooth voltage in respect of time, and described sawtooth wave is with the fluctuation of 0V magnitude of voltage symmetry.
4. the focusing of disk drive unit according to claim 2 biasing method of adjustment, it is characterized in that: described steps A mouth, the frequency of described driving voltage are 0.5Hz to 6Hz.
5. according to the focusing biasing method of adjustment of any described disk drive unit among the claim 1-4, it is characterized in that: described step C comprises the steps:
C1, described optical head detector adopt four picture limit detectors, and this detector will be in the facular area light intensity of each picture limit and carry out opto-electronic conversion respectively;
C2, detect the corresponding voltage of each picture limit respectively;
C3, computing module calculate the focus error signal amount according to the corresponding voltage of described each picture limit, and described focus error signal amount is pressed summation and even numbers to look like to ration the power supply for odd number looks like to ration the power supply and pressed the poor of summation;
C4, memory module be according to described focus error signal amount and corresponding time relation, produces the focus error signal curve of focus error signal amount and corresponding time formation.
6. the focusing of disk drive unit according to claim 5 biasing method of adjustment, it is characterized in that: described step e comprises the steps:
E1, setting one focus on biasing tolerance limit [e
0, e
0], wherein, e
0For on the occasion of;
E2, according to focusing on torquer sensitivity K, calculating voltage value tolerance limit, that is, [e
0/ K, e
0/ K];
E3, according to described extreme value generation magnitude of voltage, carry out following operation:
E31, if this extreme value generation magnitude of voltage is positioned among the magnitude of voltage tolerance limit, get described benchmark spacing for adjusting as a result spacing and exporting display module to;
E32, if this extreme value generation magnitude of voltage is positioned at outside the magnitude of voltage tolerance limit, adjust described benchmark spacing, to benchmark spacing renewal, repeating step A is to step e 2 with adjusted spacing.
7. the focusing of disk drive unit according to claim 6 biasing method of adjustment, it is characterized in that: among the described step D, described extreme value is the maximal value or the minimum value of focus error signal amount.
8. the focusing of disk drive unit according to claim 6 biasing method of adjustment, it is characterized in that: among the described step D, described extreme value is presented as the absolute value of focus error signal amount more than or equal to a threshold values of setting, or the mean value that is associated with described threshold values.
9. the focusing offset adjusting apparatus of a disk drive unit, comprise disk drive unit, Amici prism (4), optical head detector (5) and center processing unit (6), described disk drive unit comprises disk holder (11), unit pedestal (12), object lens (13), focuses on torquer (14) and laser instrument (15), described disk holder (11) is installed on the unit pedestal (12), and described focusing torquer (14) drives object lens (13) and moves; Described Amici prism (4) places the light path of laser instrument (15) and object lens (13), receives the reflected light of CD, and it is reflexed to optical head detector (5); Described center processing unit (6) receives the electric signal after optical head detector (5) opto-electronic conversion, carry out corresponding calculating, processing, the output result, it is characterized in that: described center processing unit (6) comprises computing module (61), memory module (62), comparison module (63) and display module (64), wherein
Described computing module (61) receives the electric signal of optical head detector (5) output, calculates the focus error signal amount, and computing information is sent to memory module (62);
Described memory module (62) receives, preserves the driving voltage data that put on focusing torquer (14), the computing information of computing module (61) output;
Described comparison module (63) calls the information in the memory module (62), obtains extreme value generation magnitude of voltage, and described extreme value generation magnitude of voltage and magnitude of voltage tolerance limit are compared, and comparative result exports display module (64) to.
10. the focusing offset adjusting apparatus of disk drive unit according to claim 9 is characterized in that: described optical head detector (5) is four picture limit detectors.
11. the focusing offset adjusting apparatus of disk drive unit according to claim 9 is characterized in that: also be provided with quarter wave plate (7) in the light path of described laser instrument (15) and object lens (13).
12. the focusing offset adjusting apparatus according to claim 9 or 10 or 11 described disk drive units is characterized in that: also be provided with collimation lens (3) in the light path of described laser instrument (15) and object lens (13).
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100220676A CN100392732C (en) | 2005-11-09 | 2005-11-09 | Method and apparatus for adjusting focusing bias of optical disk drive unit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100220676A CN100392732C (en) | 2005-11-09 | 2005-11-09 | Method and apparatus for adjusting focusing bias of optical disk drive unit |
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| CN100392732C true CN100392732C (en) | 2008-06-04 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101335022B (en) * | 2007-06-26 | 2011-01-05 | 宏阳科技股份有限公司 | Correcting method for CD ROM focus loop changing |
| CN102175153B (en) * | 2011-03-08 | 2013-09-11 | 东莞宏威数码机械有限公司 | Laser beam focusing spot detection system |
| CN102800335A (en) * | 2011-05-25 | 2012-11-28 | 广明光电股份有限公司 | Compact disk drive focusing voltage correction method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0877579A (en) * | 1994-09-08 | 1996-03-22 | Sony Corp | Method and device for adjusting focus bias |
| JPH08185634A (en) * | 1995-01-04 | 1996-07-16 | Hitachi Ltd | Focus offset adjusting device |
| JPH1083543A (en) * | 1996-09-04 | 1998-03-31 | Clarion Co Ltd | Focus servo circuit |
| JP2001014692A (en) * | 1999-06-30 | 2001-01-19 | Pioneer Electronic Corp | Automatic focus bias adjusting device |
| CN2632808Y (en) * | 2003-06-18 | 2004-08-11 | 天津三星电子有限公司 | Optical pickup head device by semiconductor laser |
-
2005
- 2005-11-09 CN CNB2005100220676A patent/CN100392732C/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0877579A (en) * | 1994-09-08 | 1996-03-22 | Sony Corp | Method and device for adjusting focus bias |
| JPH08185634A (en) * | 1995-01-04 | 1996-07-16 | Hitachi Ltd | Focus offset adjusting device |
| JPH1083543A (en) * | 1996-09-04 | 1998-03-31 | Clarion Co Ltd | Focus servo circuit |
| JP2001014692A (en) * | 1999-06-30 | 2001-01-19 | Pioneer Electronic Corp | Automatic focus bias adjusting device |
| CN2632808Y (en) * | 2003-06-18 | 2004-08-11 | 天津三星电子有限公司 | Optical pickup head device by semiconductor laser |
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