DVD激光头大全
DVD机的激光头
DVD机的激光头，是从DVD光盘拾取信息的执行部件。
激光头工作的时候，首先将激光二极管发出的激光经过光学系统分成束光射向碟片，然后，从碟片上反射回来的光束再照射到光电接收器上再变成电信号。
激光头在读取信号的过程中，就是让激光在碟上扫过时与信号相遇。
DVD碟上有肉眼看不见的，排得密密麻麻称作坑点的小凹点，这些小凹点就是数据信息所在，它们排列成一圈圈的同心圆。
因为光碟的读取效率是与激光的波长二次方成反比的，激光的波长越短读取效率就越好，所以，激光头发出的激光波波长被聚焦得很短很短(只有0.65微米左右)。
DVD机必须兼容播放CD和VCD碟。
不同的光盘因为结构不同，对激光的要求也有不同，这就要求DVD激光头在读取不同盘片时要采用不同的光功率。
目前，DVD机普遍采用的是红色半导体激光器。
但是，蓝色半导体激光的波长更短，所以，蓝色半导体激光器才是以后DVD激光源的发展方向。
目前DVD播放机的光头的种类可以分为单激光器方式和双激光器方式两种，而这两种的每一种又可细分为几种：单激光器方式只有一个激光发射器，只能发射650nm的激光，故无法兼容CD-R。
具体又有以下几种方式：(1)双透镜方式，采用两个焦距不同的透镜，分别用于DVD和CD系统，透镜必须采用机械方式进行切换。
(2)双焦点透镜方式，全息技术，在透镜上做环状切割。
(3)快门方式(孔径控制方式)。
双激光器方式由于采用了两个激光器，能发射两种不同波长，故能读取CD-R。
有两种方式：(1)双激光头方式，备有两套激光器和透镜系统，分别用于CD和DVD。
(2)双激光器单光路方式，备有分别适用于DVD和CD的专用激光器，光路和透镜系统则利用棱镜等实现公用。
由于DVD与CD/VCD规格的差异，光源波长的不同，所以DVDROM无法读取CD/VCD，CD-ROM也无法读取DVD，但DVD要向下兼容，所以各家生产商有不一样的办法来兼顾CD/VCD。
因为光源波长及盘片厚度不同，要正确读取盘片有四种办法：换双镜头：这是东芝最早提出并应用的，也是目前使用最广泛的。
影碟机激光头原理
影碟机激光头原理
影碟机激光头是一种使用激光光束读取光盘信息的设备。
其原理如下：
1. 发射激光：激光头内部有一个激光发射二极管，它产生和发射激光束。
2. 聚焦光束：通过一组透镜系统使激光束聚焦到光盘上的信息层上。
透镜系统主要有三个，分别是科尔曼透镜（Collimation lens）、一合目透镜（divergence lens）和聚焦透镜（focus lens）。
3. 反射光束：激光束照射到光盘表面反射回激光头。
4. 接收光束：经过反射后的光束再次通过透镜系统传回到光电二极管上。
光电二极管会将激光光束转换为电信号。
5. 读取信号：激光头接收到的电信号会被转换为数字信号，然后通过解码和处理，读取出光盘上的数据信息。
需要注意的是，激光头的反射光束会遇到光盘上的凹凸不平的微小变化，这些变化就是光盘上的信息。
激光头会根据光束的反射情况来判断信息的变化，从而实现数据的读取。
dvd影碟机内部构造机械传动机构和激光头组件的结构特点机械传动机构
dvd影碟机内部构造机械传动机构和激光头组件的结构特点机械传动机构1. 引言1.1 概述随着科技的不断发展，DVD影碟机已经成为我们日常生活中常见的娱乐设备之一。
而作为DVD影碟机的核心部件，内部构造扮演着至关重要的角色。
本文将详细介绍DVD影碟机内部构造中两个关键组件：机械传动机构和激光头组件的结构特点。
1.2 文章结构本文主要分为五个部分进行讨论。
引言部分作为文章开篇，旨在对研究主题进行概述、阐明文章结构，并明确文章的目的。
其后将依次介绍DVD影碟机内部构造机械传动机构和激光头组件的结构特点，并探讨它们在整个系统中的作用和重要性。
接着是对机械传动与激光头之间关联性与配合度研究以及针对DVD影碟机内部结构进行优化改进建议的讨论与分析。
最后，在结论部分对本文所涉及到的内容进行总结，并展望了机械传动机构和激光头组件在DVD影碟机中的应用前景，并提出进一步研究的方向和建议。
1.3 目的本文旨在深入研究DVD影碟机内部构造中机械传动机构和激光头组件的结构特点，并探讨它们在整个系统中的作用和功能。
通过对两者之间关联性与配合度进行研究，以及针对内部结构提出优化改进建议，本文将为DVD影碟机制造商、维修人员以及相关科研工作者提供有益的参考和指导。
此外，我们还将展望机械传动机构和激光头组件在未来DVD影碟机发展中的应用前景，并提出进一步研究的方向和建议，以推动该领域的发展。
2. DVD影碟机内部构造机械传动机构的结构特点2.1 光驱组件介绍DVD影碟机的光驱组件是实现读取和播放光盘内容的核心部分。
它主要由转盘、光头及相关传动装置组成。
转盘通过电动马达带动，并能够使光头准确地读取光盘上的信息。
光头是负责发射激光和感应激光反射信号的关键元素。
2.2 机械传动机构的作用和意义在DVD影碟机中，机械传动机构扮演着连接各个关键组件并实现它们配合运行的重要角色。
它通过传递马达产生的力量和运动，使得转盘能够旋转，从而让光头在光盘表面按照特定路线进行移动，读取数据。
1200XH激光头规格书
This Pick-up is using the gold-plated connector to complSo, use gold-plated FFC(FPC) and gold-plated connector in customer's side as well.CONTENTS 1.SCOPE2.GENERAL SPECIFICATIONS3.STANDARD CONDITIONS OF EVALUATION 4.STANDARD PERFORMANCE5.RELIABILITY6.MAIN PARTS7.INDICATION8.PACKING SPECIFICATIONS1Fig. 1 CONNECTIONS2Fig. 2 APPEARANCE3Fig. 3 LASER DRIVE CIRCUIT4Fig. 4MEASURING CIRCUITSCOPEDVDThese specifications apply to the optical pick-up for DVD-ROM Drive.If any inconvenience occurs, negotiation is required to settle the matter by the following guide lines.The parts and manufacturing process are subject to change for improvements within the range of the specifications.These specifications are subject to change for improvements by negotiations in advance.GENERAL SPECIFICATIONSItemsSpecificationsDVD CDLight source658 nm15 nmLaser diodeWave length785 nm22nmLaser diode Wave lengthObjective lensNA 0.6 , WD=1.64 mm Aspherical plastic lens NA 0.47, WD = 1.28 mmAspherical plastic lens Focus Detection Astigmatic methodAstigmatic method Tracking Detection Differential Phase Detection 33 spots methodPhoto detector 10OEIC (I/V )10-devided optical-electronic IC (I/V amplifiers,) Actuator systemLens travel ()(from standard operate point)Operation temp.Storage temp.Mass Appearance22-direction Objective lens driving method -(DVD)() 0.95 mmFocusing(DVD) more than 0.95 mm() 0.70 mmless than 0.70 mm -(CD) () 0.85 mmFocusing(CD) more than 0.85 mm() 0.95 mmless than 0.95 mm0.45 mmTracking more than |0.45| mm 1070307014gSee Fig. 23.STANDARD CONDITIONS OF EVALUATION(1)Test posture Optical axis of objective is direction of gravity and projecting light fromthe objective should be upward.(2)25 2Environment Temperature60 % 5 %[RH]Humidity: 15 35 ,: 45 %75 %[RH].We can adopt temperature range 15 %35,humidity range 45 %75 %[RH],If it occurs no doubt about judgment.(3)()Evaluation disc Use the disc that we admit for evaluation.MCD-162B (Made by TEAC CORPORATION)Use the disc that we admit for evaluation.(4)CJ3Evaluation Use Hitachi standard measuring equipment.(for CJ3)apparatus 3Laser drive circuit is shown in fig.34Measuring circuit is shown in fig.4Jitter meterDVD MWJ-6392A (Made by MEGURO ELECTRIC CO.)CD MJM-631C (Made by MEGURO ELECTRIC CO.)(5)(1)EvaluationDisc speed normal speed4.STANDARD PERFORMANCE4 - 1Optical PerformanceItems Spec.RemarksDVD CD(1)Objective LensfFocal distanceNANumerical apertureWDWorking distance3.05 mm0.61.64mm3.07 mm0.471.28 mm(2)Objective emission lightP0Emission light power P maxWavelength0.3 mW0.5 mW658 nm15 nm0.3 mW0.5 mW785 nm22 nmTypicalMaximumat 254 - 2Electrical performanceItems Spec.Remarks(1)(DVD)Laser diodeMaximum ratingsV revReverse voltageLight output powerElectrical characteristicsV opOperating voltageI opOperating currentImMonitor current2.0 V7 mW2.2 V Typical28 mA Typical22 mA Typica80A Typical90 A TypicalNV6D05FT(RENESAS)RLD2WMFL3(ROHM)Photo-diode : 20 VMax 2.6 V at 25Max 65 mA at 70 (NV6D05FT)Max 52 mA at 70 (RLD2WMFL3)NV6D05FTRLD2WMFL3(2)(CD)Laser diodeMaximum ratingsV revReverse voltageLight output powerElectrical characteristicsV opOperating voltageI opOperating currentImMonitor current2.0 V7 mW2.1 V Typical1.9 V Typical32 mA Typical18 mA Typical75A Typical135 A TypicalNV6D05FT(RENESAS)RLD2WMFL3(ROHM)Photo-diode : 20 VMax 2.6 V at 25 (NV6D05FT)Max 2.3 V at 25 (RLD2WMFL3)Max 65 mA at 70 (NV6D05FT)Max 52 mA at 70 (RLD2WMFL3)NV6D05FT(RENESAS)RLD2WMFL3(ROHM)(3)(CD/DVD)High frequency moduleVccSupply VoltageIccOperation CurrentOscillation frequency4.5V5.2 V27 5 mA (Vcc=5.0V)377 MHz50 MHz21pinconnector No.21The combinations of DVD LD, CD LD and HFM refer to Fig.3-4DVD CD3-44 - 2Electrical performanceItems Spec.Remarks(4) 10OEIC10-divided optical-electronic ICMaximum ratingsVccSupply voltageElectrical characteristicsVcReference voltage input(3dB )FcCut off frequency(A1A4RF)DVDCDDC offsetV(RF)6V2.1 VMore than 40 MHzMore than 30 MHz0.1V(A+B+C+D)1.40.14I/V(NEC)4.55.5 VRecommend supply voltage“Supply voltage conditionshould be to keep[Vcc Vs]at any time.”1.52.75 VRecommend supply voltageVcc-Vc 2.0V- 13 pinconnector No.13Typical 80 MHzTypical 50 MHzat Vcc=5V Rl=10kfrom Vs- 8 pin(from GND)connector No.8(5)Actuator coilMaximum ratingsAllowable focusing currentAllowable tracking current180mArms240mArms 1s180mArms240mArms 1sSupply to each coil, exclusivelyContinuousWithin 1 secContinuousWithin 1 secDVD Output signal characteristicsItems Standard Spec. 1070Spec.Reliability Spec. Remarks signallevel(Jitter(Data to Clock) less than 10 %initial valueless than14 %initial valueless than 14 %connector No.8Normal SpeedFocus error signal ( FES ) = (A+C)Signal level initial value Linear rangeFocusing errorm ofinitial valuem ofinitial valuePolarity When the disc is closer than the focal point, FES output polarity is +. PD balancePD balance T from initial value from initial valueCD Output signal characteristicsItems Standard Spec.1070Spec.Reliability Spec. Remarks signalLevelJitter (less than 26 ns initial valueless than 32 nsinitial valueless than 32 nsconnectorNo.8Normal speedFocus error signal ( FES )Signal level initial value initial value Linear rangem(<Focusing errorm ofinitial value initial valuePolarity When the disc is closer than the focal point, FES output polarity is +. Over shootTracking error signal ( TES )Signal level initial value initial valueOff center from initial value from initial valuePhase difference from initial value from initial valuePolarity When the track is shifting toward the disc center, TES output polarity is4 - 3Actuator characteristicsSpec.ItemsFocusingTrackingReliability spec.RemarksCoil DC resistance DCDC SensitivityAcceleration sense. F 0Q 0Phase turbulence(fh)Resonance peak5.41.5 mm/V 3dB110m/s 2/V2050Hz 8Hz 20 dB 153519k Hz(Typ. 32 kHz)4.11.3 mm/V3dB100m/s 2/V2053Hz 8Hz 20 dB153520 kHz(Typ. 25 kHz)Within30 % of Initial val.Within 20 % of Initial val.Within20 % of Initial val. Within20 % ofInitial val.FPCWith FPC 0.1FPC Resistance :Typical 0.1at 200Hz5004k HzPolarityFocusing direction Tracking direction1 pinWhen Connector no.1 is polarity, the objective approaches to the disc.3 pinWhen Connector no.3 is polarity, the objective shifts toward the periphery of the disc center.5.RELIABILITYItemsSpecifications.High temperature operation test704 h10 minThe samples shall be kept at 60 for 4 hours , then operate 10 minutes. Meet the (1070) spec. Low temperature operation test104 h 10 minThe samples shall be kept at 10 for 4 hours , then operate 10 minutes. Meet the (1070) spec.Preservation test of high temperature7024 h16 hThe samples shall be kept at 70for 24 hours , thenpreservation test kept at standard condition for 16hours.Meet the reliability spec. Preservation test of low temperature3024 h16 hThe samples shall be kept at30for 24 hours , thenpreservation test kept at standard condition for 16 hours. Meet the reliability spec. Preservation test of hightemperature & high humidity .40, 90 %[RH]48 h16 hThe samples shall be kept at 40,90 %[RH] for 48 hours ,and high humidity then kept at the standard condition for 16 hours. Meet the reliability spec. Temperature cycling test20(1 h) 60(1 h)80/1 h 516 hApplied 20(1 h)60(1 h), 5 cycles (temperature slope80/1 h) , then kept at the standard condition for 16 hours.Meet the reliability spec.Shock test784 m/s 26 ms 31Peak acceleration 784 m/s 2 , Half sine waveform pulse for 6 ms widths , 3-directions , one time each. Meet the reliability spec .Vibration test23.5 m/s 210 Hz 50 Hz (5min)320 minAcceleration 23.5 m/s 2, 10 Hz 50 Hz linear sweep (one round 5minutes) , 3-directions , 20 minutes each. Meet the reliability spec.ItemsSpecifications.Life of laser After 3,000 hours operation at 25 be less than 0.1 %.Except damaged by static electricity. (Laser current should be within +50 % of the initial vale.)MAIN PARTS(SAFETY STANDARD)6-1 ConnectorPartsMaterial ManufactureMaterial Generic NameMaterial TypeUL Flame ClassUL File No.DSM JAPAN ENGINNERING PLASTICS K K PA46TS250F6D94V-0 E172082 DSM ENGINNERING PLASTICS B VPA46 TS250F8 94V-0 E47960 DSM engineering plastic INC.PA46TS250F694V-0 E43392Housing94V-0POLYPLASTICS CO LTD FORTLON DIV PPS 1140-A1 94V-0 E109088 KURARAY CO LTD PA9T G2450 94V-0 E90350 Toray industries INC.PPSA504X9094V-0 E41797Actuator94V-0H6MainPWBPhotoDetectorPWBINDICATION2Position of indications is shown in Fig.2ManufacturingLast Figure Month DaySerial No.Control No.Packing specifications250 Pieces Box250480440155Mass5.4 kgPacking SpecificationHANDLING9 - 1Cautions on assembly(1)How to assemble2)Assembling reference is guide-bar. ( See fig. 2)Apply grease to the Bearings. Recommendation is shown below.SANCOAL MEN-223R GREASEMain bearings TEL 048- 422-3305SANCOAL MEN-223R GREASESub bearings TEL 048- 422-3305TEL 048- 422-3305When applying the grease to main bearings and sub bearings, apply appropriate volume grease to Pick-up not to adhere the inside of Pick-up. The grease of the inside of Pick-up may cause the deterioration of performance or reliability.Check the sliding lifetime of bearings on your mechanism. If the pinion gear is placed on inner disc or outer disc in the rack & pinion mechanism, the bearings may be much damaged by rotating moments.Use a precision mechanism. Recommendation is shown below.24.5 mm0.08 mmDistance between main guide-bar and turntable center.Pick-up mechanism should be floated from other parts by damping materials.(2)Laser drive circuit3HFOEIC HFIf use another laser drive circuit, adjust HF signal level as below.Item VtopDVD (A+B+C+D) 880 mVCD (A+B+C+D) 1000 mVWe solder the Short land on PWB before shipment to protect laser diode.Open the short lands after you connect pick-up with your circuit by flat cable .When you unstrap the short solder for the laser diode protection in the condition which doesn'tconnect by a flat cable, the laser diode and OEIC may destroy by static electricity.(3)Power supplyVc VccVc Vcc OEICPower supply voltage condition should be Vc Vcc at any time. Even Vc is higher than Vcc for instanttime, OEIC may be burn out by over current.(4) FFCFFC100mm100mm~We recommend a FFC length of less than 100mm for oscillation prevention.When you use FFC length of more than 100mm, please add a filter to A-D and RF line for oscillation prevention.This Pick-up is using the gold-plated connector. So, please use gold-plated FFC(FPC) and gold-plated connector so on in customer’s side as well.If the parts at points of contact to connector were plated by metal except gold, the connecting defect happen because of chemical reaction. (Oxidized insulting membrane is built up)(5)(EMI)Solution of improving radiation (EMI)DVD-LD(DVD-PLAYER)FCC(Vcc=5.0[v])(a)(1,000pF)(a) Capacitor (1,000pF) is added to the GND pattern steady as much as possible near the connector.9 - 2Cautions on handling(1)Do not disassemble or adjust this pick-up.(2)StorageDo not leave this pickup in high temperature and humidity.Be sure to prevent this pick-up from static electricity , dust and excessive forces.Do not leave this pick-up without a cover for the dust.(3)HandlingDo not shock to this pick-up.Don't touch the parts as follows. To touch them may cause big trouble.Trim-potentiometer Laser diode Fixate plate of OEIC High frequency ICObjective Actuator Include connected point actuator and PWBThe laser diode soldering portion of is sharp, be careful especially because it is dangerous.ActuatorFig.OEICFixate plate Connected point actuator and PWB High frequency ICof OEIC and DVD laserTrim-potentiometer(2 pcs)Be sure no dust or soil on handling and leaving. Because, dust or soil on the objective causes the remarkable damage. If the dust is on the objective, blow it away by clean air, also, if the dust or soil remain on the objective, clean by the cleaning liquid (B4) made by JCBINDUSTRY Ltd. Noalternative,and an applicator (no waste thread type).Make sure that the person who handles this pick-up is earthed by wrist-strap etc.Insert the flat cable which is connected pick-up and your circuit vertically to the root of pick-ups connector, not to touch the next pattern (pin) and not to cause the failure connection.Don't leave or carry in the condition which unstrap short solder not to destroy the laser diode orOEIC by static electricity.When taking pick-up out from blister-pack, hold the case of pick-ups not to touch Actuator as shown in Fig.d. Do not hold as shown in Fig.e. If touch OEIC and other parts, it may cause the deterioration of performance or reliability.Blister-pack The case of pick-upFig.d Fig.eAfter taking pick-up out from blister-pack, hold a slide-base portion as shown in Fig.f and carry it.Fig.fAn abnormal power on the connector may cause some damages on the part of the connection between the connector and PWB. When you insert or pull-out the flat cable, don’t add an abnormal power on the connector.Be sure to earth to the manufacturing equipments.Do not approach magnetic materials.Hold a slide base portion to carry.( Refer to the left figure)HITACHI1Fig.1 Connections0.5 mm pitch FFC ConnectorFFC(FPC) thickness: 0.3 mm0.05 mmwidth: 12.5 mm0.07 mmFLead spotHITACHI)Fig.3 1 Laser Drive Circuit32CD DVDFig.3 2 CD DVD Switching Circuit DiagramHITACHIFig3-4 High Frequency Module (HFM) timing chart4/CDFig.4 Measuring Circuit (DVD/CD)5Fig.5 Measuring Circuit6(a) ( CD )Fig.6(a) Measuring Circuit6(b) ( CD )Fig.6(b) Measuring CircuitDVD HF OUT Frequency ResponseNon EQ OUT EQ OUT7(a) DVD HFFig.7(a) DVD HF OUT Frequency Response of Hitachi measurement circuitDVD RF OUT Frequency Response7(b) DVD RFFig.7(b) DVD RF OUT Frequency Response of Hitachi measurement circuit7(c) CD HFFig.7(c)CD HF OUT Frequency Response of Hitachi measurement circuitCD RF OUT7(d) CD RFFig.7(d)CD RF OUT Frequency Response of Hitachi measurement circuit。
光头大全
這兒展示了多達35種的光碟機光頭圖片，包括刻錄機、DVD光碟機的光頭。
1、松下0403DVD頭
2、松下0381DVD頭
3、松下0441DVD頭
4、三星DVD頭6X/8X
5、三星DVD頭
6、DVD頭
7、先鋒DVD頭8、先鋒DVD 9、HOP-1000美達、源興、
DVD頭
10、SONY220EDVD頭11、DVD用雙光頭鐳射頭12、明基BenQ8432鐳射頭
13、PXR-550 14、KRS-180用於SONY系
列刻錄機
15、理光刻錄機
16、SUP3200用於
SONY611
三星24X 17、KRS-200A
KRS-202A
18、HOP-A1多達32X以上
光碟機用此光頭
19、HOP-E1用於旗艦
36X
假PHILIPS24X也是用此
光頭
20、KSS570用於
SONY311/511/美上美8X
21、PHILIPS1318用於宏基
4OX
22、PXR352用於美上美
24X以上
23、181用於松下系列光碟
機
24、HOP-Z117線用於源興
24X
25、SPU3200 17線用於
華碩40X
26、三星刻錄機鐳射頭27、三星12XDVD鐳射頭
28、美上美刻錄鐳射頭29、松下8439RW刻錄機鐳
射頭
30、三星康寶鐳射頭
31、奧美嘉刻錄鐳射頭32、KRS-330A(310A)鐳射
頭
33、理光7063刻錄機鐳射頭
34、理光7080刻錄機鐳射
頭35、YAMAHA6424刻錄機
鐳射頭。
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DVD机的激光头
DVD机的激光头，是从DVD光盘拾取信息的执行部件。
激光头工作的时候，首先将激光二极管发出的激光经过光学系统分成束光射向碟片，然后，从碟片上反射回来的光束再照射到光电接收器上再变成电信号。
激光头在读取信号的过程中，就是让激光在碟上扫过时与信号相遇。
DVD碟上有肉眼看不见的，排得密密麻麻称作坑点的小凹点，这些小凹点就是数据信息所在，它们排列成一圈圈的同心圆。
因为光碟的读取效率是与激光的波长二次方成反比的，激光的波长越短读取效率就越好，所以，激光头发出的激光波波长被聚焦得很短很短(只有0.65微米左右)。
DVD机必须兼容播放CD和VCD碟。
不同的光盘因为结构不同，对激光的要求也有不同，这就要求DVD激光头在读取不同盘片时要采用不同的光功率。
目前，DVD机普遍采用的是红色半导体激光器。
但是，蓝色半导体激光的波长更短，所以，蓝色半导体激光器才是以后DVD激光源的发展方向。
目前DVD播放机的光头的种类可以分为单激光器方式和双激光器方式两种，而这两种的每一种又可细分为几种：单激光器方式只有一个激光发射器，只能发射650nm的激光，故无法兼容CD-R。
具体又有以下几种方式：(1)双透镜方式，采用两个焦距不同的透镜，分别用于DVD和CD系统，透镜必须采用机械方式进行切换。
(2)双焦点透镜方式，全息技术，在透镜上做环状切割。
(3)快门方式(孔径控制方式)。
双激光器方式由于采用了两个激光器，能发射两种不同波长，故能读取CD-R。
有两种方式：(1)双激光头方式，备有两套激光器和透镜系统，分别用于CD和DVD。
(2)双激光器单光路方式，备有分别适用于DVD和CD的专用激光器，光路和透镜系统则利用棱镜等实现公用。
由于DVD与CD/VCD规格的差异，光源波长的不同，所以DVDROM无法读取CD/VCD，CD-ROM也无法读取DVD，但DVD要向下兼容，所以各家生产商有不一样的办法来兼顾CD/VCD。
因为光源波长及盘片厚度不同，要正确读取盘片有四种办法：换双镜头：这是东芝最早提出并应用的，也是目前使用最广泛的。
第4章 VCD、DVD机激光头的故障检修实例
激光二极管的检测： 激光二极管的检测：
激光二极管 供电端AL 供电端AL
接地端K 接地端K
光敏二极 管组件 输出端AP 输出端AP
激光二极管引脚端 30
激光二极管的检测： 激光二极管的检测：
检测激光二极管就是检测激光二极管供电端AL和接地端K 检测激光二极管就是检测激光二极管供电端AL和接地端K之间的阻 AL和接地端 15kΩ左右 值，为15kΩ左右
VCD/DVD机激光头的故障检修实例 VCD/DVD机激光头的故障检修实例
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聚焦线圈的检测： 循迹线圈的检测： 聚焦线圈的检测： 循迹线圈的检测
聚焦线 循迹线 圈焊点 圈焊点
使用指针万用表检测激光头循迹线圈， 使用指针万用表检测激光头聚焦线圈，正常情况下的阻值为7.0Ω 使用指针万用表检测激光头循迹线圈 使用指针万用表检测激光头聚焦线圈，正常情况下的阻值为7.0Ω 左右，使用万用表测量的瞬间整个激光头有上下移动的现象 使用万用表测量的瞬间整个激光头有左右移动的现象 左右，使用万用表测量的瞬间整个激光头有上下移动的现象 29
VCD/DVD机激光头的结构及检测方法 VCD/DVD机激光头的结构及检测方法
VCD/DVD机激光头的故障检修实例 VCD/DVD机激光头的故障检修实例
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VCD/DVD机激光头的结构及检测方法 VCD/DVD机激光头的结构及检测方法
2
光盘及其信息形式： 光盘及其信息形式：
旋转方向为逆时针（从信息面方向看） 旋转方向为逆时针（从信息面方向看）
永磁铁
循迹线圈及支撑机构
聚焦线圈及导向机构
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驱动齿条
导轴
进给驱动 齿轮组 进给电机
激光头的进给机构