1、圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2電荷耦合器件CCD 線陣CCD 面陣CCD表面溝道CCD(SCCD),電荷包存儲在半導(dǎo)體與絕緣體之間的界面，并沿界面轉(zhuǎn)移。體溝道CCD(BCCD),電荷包存儲在離半導(dǎo)體表面一定深度的體內(nèi)，并在半導(dǎo)體內(nèi)沿一定方向轉(zhuǎn)移CCD類型電荷耦合器件CCD 線陣CCD 面陣CCD表面溝道CCD(S 1. 電荷耦合器件的工作原理1.1、CCD工作原理CCD光信息電脈沖脈沖只反映一個光敏元的受光情況脈沖幅度的高低反映該光敏元受光照的強(qiáng)弱輸出脈沖的順序可以反映一個光敏元的位置完成圖像傳感 1. 電荷耦合器件的工作原理1.1、CCD工作原理

2、CCD光特點(diǎn)：以電荷作為信號基本功能：電荷的存貯和轉(zhuǎn)移CCD基本工作原理信號電荷的產(chǎn)生信號電荷的存貯信號電荷的傳輸信號電荷的檢測特點(diǎn)：以電荷作為信號基本功能：電荷的存貯和轉(zhuǎn)移CCD基本工作1.1.1 電荷存貯 CCD 是由規(guī)則排列的金屬氧化物半導(dǎo)體（Metal Oxide Semiconductor,MOS）電容陣列組成。 MetalOxideSemiconductor1.1.1 電荷存貯 CCD 是由規(guī)則排列的金屬金屬VG氧化物（SiO2）半導(dǎo)體(PSi)電子勢阱界面勢如果有光入射到半導(dǎo)體硅片上，在光子的作用下，半導(dǎo)體硅產(chǎn)生電子空穴對，由此產(chǎn)生的光電子被表面的勢阱所吸收。而空穴被電場排斥出耗

3、盡區(qū)。 當(dāng)在金屬電極上加正電壓VG時，在電場的作用下，電極下型區(qū)域里的多數(shù)載流子空穴被排斥、驅(qū)趕，形成了一個耗盡區(qū)。而對于少數(shù)載流子電子，電場則吸引它到電極下的耗盡區(qū)。耗盡區(qū)對于帶負(fù)電的電子來講是一個勢能很低的區(qū)域稱為“勢阱”。勢阱積累電子的容量取決于勢阱的“深度”，而表面勢的大小近似與柵壓VG成正比。金屬VG氧化物半導(dǎo)體電子勢阱界面勢如果有光入射到半導(dǎo)體硅片上勢阱內(nèi)吸收的光電子數(shù)量與入射光勢阱附近的光強(qiáng)成正比。這樣一個MOS結(jié)構(gòu)單元就稱光敏單元或一個象素；而將一個勢阱所吸收集的若干個光生電荷稱為一個電荷包。 通常在半導(dǎo)體硅片上制有成千上萬個相互獨(dú)立的MOS光敏單元，如果在金屬電極上加上正電壓

4、，則在半導(dǎo)體硅片上就形成成千上萬的個相互獨(dú)立的勢阱。如果此時照射在這些光敏單元上是一副明暗起伏的圖像，那么這些光敏元就會產(chǎn)生出一幅與光照強(qiáng)度相對應(yīng)的光電荷圖像，因而得到影像信號。勢阱內(nèi)吸收的光電子數(shù)量與入射光勢阱附近的光強(qiáng)成正比。這樣一個1.1.2.電荷耦合 CCD器件每一單元（每一像素）稱為一位，有256位、1024位、2160位等線陣CCD。CCD一位中含的MOS電容個數(shù)即為CCD的相數(shù)，通常有二相、三相、四相等幾種結(jié)構(gòu)，它們施加的時鐘脈沖也分為二相、三相、四相。二相脈沖的兩路脈沖相位相差1800；三相及四相脈沖的相位差分別為1200、900 。當(dāng)這種時序脈沖加到CCD驅(qū)動電路上循環(huán)時，將

5、實(shí)現(xiàn)信號電荷的定向轉(zhuǎn)移及耦合。 圖所示TCD1206的相鄰兩像元，每一位含MOS電容2個 取表面勢增加的方向向下，工作過程如圖所示： 1.1.2.電荷耦合 CCD器件每一單元（每一像素）稱不對稱勢阱每一位下兩個12 t=t1時 t=t2時 t=t3時 t=t4時12t1t2t3TCD1206二相驅(qū)動波形（1、2相位差1800）t4at=t1時 ，1電極處于高電平，而2電極處于低電平。由于1電極上柵壓大于開啟電壓，故在1下形成勢阱，假設(shè)此時光敏二極管接收光照，它每一位（每一像元）的電荷都從對應(yīng)的1電極下放入勢阱。 不對稱勢阱12 t=t1時 t=b t=t2時 ，1電極上柵壓小于2電極上柵壓，故

6、1電極下勢阱變淺，勢阱變深，電荷更多流向2電極下。（由于勢阱的不對稱性，“左淺右深”，電荷只能朝右轉(zhuǎn)移 c t=t3時 ，2電極處于高電平，而1電極處于低電平，故電荷聚集到2電極下，實(shí)現(xiàn)了電荷從1電極下到2電極下的轉(zhuǎn)移。 d 同理可知，t=t4時 ，電荷包從上一位的1電極下轉(zhuǎn)移到下一位的1電極下。因此，時鐘脈沖經(jīng)過一個周期，電荷包在CCD上移動一位。 b t=t2時 ，1電極上柵壓小于2電極上柵壓，故1.1.3 電荷注入 光注入方式 當(dāng)光照射到CCD硅片上時，在柵極附近的體內(nèi)產(chǎn)生電子空穴對，其多數(shù)載流子被柵極電壓排開，少數(shù)載流子則被其收集到勢阱中形成信號電荷。在CCD中，電荷注入分為兩類：光注

7、入和電注入。N為入射光的光子流速率；A為光敏單元的受光面積，t為光注入時間1.1.3 電荷注入 光注入方式在CCD中，電荷注入分為兩12G0RGVRDT2ACRLVoutVODT3T1MOSFET（場效應(yīng)管）漏極柵極源極（直流偏置）輸出柵（器件內(nèi)部，總打開）注：. 對二相CCD，只有1、2電極 ；.2下電荷耦合進(jìn)T3 。（復(fù)位脈沖R）1.1.4 電荷檢測 CCD輸出結(jié)構(gòu)的作用是將CCD中信號電荷變?yōu)殡娏骰螂妷狠敵?，以檢測信號電荷的大小。 浮置擴(kuò)散放大器屬于電壓輸出方式，目前采用較多。其基本結(jié)構(gòu)和工作原理如下：如圖所示，給出了CCD的電壓輸出電路。放大管T1 復(fù)位管T2輸出二極管T312G0RG

8、VRDT2ACRLVoutVODT3T1MO此電荷積分器隨T2管的開與關(guān)，處于選通和關(guān)閉狀態(tài)，稱為選通電荷積分器 放大管T1是源跟隨器復(fù)位管T2工作在開關(guān)狀態(tài)輸出二極管T3始終處于強(qiáng)反偏狀態(tài)A點(diǎn)的等效電容C由T3管的結(jié)電容加上T1管的柵電容構(gòu)成，它構(gòu)成一個電荷積分器12G0RGVRDT2ACRLVoutVODT3T1MOSFET（場效應(yīng)管）漏極柵極源極（直流偏置）輸出柵（器件內(nèi)部，總打開）注：. 對二相CCD，只有1、2電極 ；.2下電荷耦合進(jìn)T3 。（復(fù)位脈沖R）此電荷積分器隨T2管的開與關(guān)，處于選通和關(guān)閉狀態(tài)，稱為選通電21RVout如圖所示為電壓輸出工作波形圖。 CCD電壓輸出工作原理為

9、： 在每個時鐘脈沖周期內(nèi)，隨著時鐘脈沖1或2的下降過程，就有一個電荷包從CCD轉(zhuǎn)移到輸出二極管T3的N區(qū)，即轉(zhuǎn)移到電荷積分器上，引起A點(diǎn)電位變化為： 21RVout如圖所示為電壓輸出工作波形圖。 CCD電由于MOS管T1的電壓增益為 式中g(shù)m為電導(dǎo)，RL為負(fù)載電阻，故T1管源極輸出電壓變化為： 對Vout進(jìn)行讀出，然后T2管柵極RG在復(fù)位脈沖R的作用下導(dǎo)通，將電荷包Q通過T2管的溝道抽走，使A點(diǎn)電位重新置在VRD值，為下一次Vout讀出作準(zhǔn)備。因?yàn)槭荖溝道，信息電荷為電子，故加負(fù)號 當(dāng)R結(jié)束，T2管關(guān)閉后，由于T1管處于A點(diǎn)的VRD電位的強(qiáng)反偏狀態(tài)，此積分器無放電回路，所以A點(diǎn)電位一直維持在V

10、RD值，直到下一個時鐘脈沖信號電荷到來為止。 由于MOS管T1的電壓增益為 式中g(shù)m為電導(dǎo)，RL為負(fù)載電阻CCD Analogy A common analogy for the operation of a CCD is as follows: An number of buckets (Pixels) are distributed across a field (Focal Plane of a telescope)in a square array. The buckets are placed on top of a series of parallel conveyor belts

11、 and collect rain fall(Photons) across the field. The conveyor belts are initially stationary, while the rain lowly fills the buckets (During the course of the exposure). Once the rain stops (The camera shutter closes) the conveyor belts start turning and transfer the buckets of rain , one by one ,

12、to a measuring cylinder (Electronic Amplifier) at the corner of the field (at the corner of the CCD) The animation in the following slides demonstrates how the conveyor belts work.CCD Analogy A common analoRAIN (PHOTONS)BUCKETS (PIXELS)VERTICALCONVEYORBELTS(CCD COLUMNS)HORIZONTALCONVEYOR BELT(SERIAL

13、 REGISTER)MEASURING CYLINDER(OUTPUT AMPLIFIER)CCD AnalogyRAIN (PHOTONS)BUCKETS (PIXELS)Exposure finished, buckets now contain samples of rain.Exposure finished, buckets nowConveyor belt starts turning and transfers buckets. Rain collected on the vertical conveyoris tipped into buckets on the horizon

14、tal conveyor.Conveyor belt starts turning aVertical conveyor stops. Horizontal conveyor starts up and tips each bucket in turn intothe measuring cylinder .Vertical conveyor stops. HorizAfter each bucket has been measured, the measuring cylinderis emptied , ready for the next bucket load.After each b

15、ucket has been me圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2A new set of empty buckets is set up on the horizontal conveyor and the process is repeated.A new set of empty buckets is 圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課

16、件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2圖像信息原理教學(xué)課件電荷耦合器件_v2Eventually all the buckets have been measur

17、ed, the CCD has been read out.Eventually all the buckets havStructure of a CCD 1.The image area of the CCD is positioned at the focal plane of the telescope. An image then builds up that consists of a pattern of electric charge. At the end of the exposure this pattern is then transferred, pixel at a

18、 time, by way of the serial register to the on-chip amplifier. Electrical connections are made to the outside world via a series of bond pads and thin gold wires positioned around the chip periphery. Connection pins Gold bond wires Bond pads Silicon chipMetal,ceramic or plastic packageImage areaSeri

19、al registerOn-chip amplifierStructure of a CCD 1.The imageStructure of a CCD 2.CCDs are are manufactured on silicon wafers using the same photo-lithographic techniques used to manufacture computer chips. Scientific CCDs are very big ,only a few can be fitted onto a wafer. This is one reason that the

20、y are so costly.The photo below shows a silicon wafer with three large CCDs and assorted smaller devices. A CCD has been produced by Philips that fills an entire 6 inch wafer! It is the worlds largest integrated circuit.Don Groom LBNLStructure of a CCD 2.CCDs are Structure of a CCD 3. One pixelChann

21、el stops to define the columns of the imageTransparenthorizontal electrodesto define the pixels vertically. Also used to transfer the charge during readoutPlan ViewCross sectionThe diagram shows a small section (a few pixels) of the image area of a CCD. This pattern is reapeated.ElectrodeInsulating

22、oxiden-type siliconp-type siliconEvery third electrode is connected together. Bus wires running down the edge of the chip make the connection. The channel stops are formed from high concentrations of Boron in the silicon.Structure of a CCD 3. One pixStructure of a CCD 4. On-chip amplifierat end of t

23、he serial registerCross section ofserial registerImage AreaSerial RegisterOnce again every third electrode is in the serial register connected together. Below the image area (the area containing the horizontal electrodes) is the Serial register . This also consists of a group of small surface electr

24、odes. There are three electrodes for every column of the image areaStructure of a CCD 4. On-chipStructure of a CCD 5.The serial register is bent double to move the output amplifier away from the edgeof the chip. This useful if the CCD is to be used as part of a mosaic.The arrows indicate how charge

25、is transferred through the device.Edge of Silicon160mmImage AreaSerial RegisterRead Out AmplifierBus wiresPhotomicrograph of a corner of an EEV CCD.Structure of a CCD 5.The seriaStructure of a CCD 6.ODOSRDRSWOutput NodeSubstrateOutput TransistorReset TransistorSummingWell20mmOutput Drain (OD)Output

26、Source (OS)Gate of Output TransistorOutput NodeRReset Drain (RD)Summing Well (SW)Last few electrodes in Serial RegisterSerial Register ElectrodesPhotomicrograph of the on-chip amplifier of a Tektronix CCD and its circuit diagram.Structure of a CCD 6.ODOSRDRSWElectric Field in a CCD 1.The n-type laye

27、r contains an excess of electrons that diffuse into the p-layer. The p-layer contains an excess of holes that diffuse into the n-layer. This structure is identical to that of a diode junction. The diffusion creates a charge imbalance and induces an internal electric field. The electric potential rea

28、ches a maximum just inside the n-layer, and it is here that any photo-generated electrons will collect. All science CCDs have this junction structure, known as a Buried Channel. It has the advantage of keeping the photo-electrons confined away from the surface of the CCD where they could become trap

29、ped. It also reduces the amount of thermally generated noise (dark current). npElectric potentialPotential along this line shownin graph above.Electric potentialCross section through the thickness of the CCDElectric Field in a CCD 1.The Electric Field in a CCD 2.During integration of the image, one

30、of the electrodes in each pixel is held at a positive potential. This further increases the potential in the silicon below that electrode and it is here that the photoelectrons are accumulated. The neighboring electrodes, with their lower potentials, act as potential barriers that definethe vertical

31、 boundaries of the pixel. The horizontal boundaries are defined by the channel stops.npElectric potentialRegion of maximum potentialElectric Field in a CCD 2.Duripixel boundaryCharge packetp-type siliconn-type siliconSiO2 Insulating layerElectrode Structurepixel boundaryincomingphotonsCharge Collect

32、ion in a CCD.Photons entering the CCD create electron-hole pairs. The electrons are then attracted towards the most positive potential in the device where they create charge packets. Each packet corresponds to one pixelpixel Charge packetp-type siliCharge Transfer in a CCD 1.In the following few sli

33、des, the implementation of the conveyor belts as actual electronicstructures is explained. The charge is moved along these conveyor belts by modulating the voltages on the electrodespositioned on the surface of the CCD. In the following illustrations, electrodes colour coded redare held at a positiv

34、e potential, those coloured black are held at a negative potential.123Charge Transfer in a CCD 1.In 123+5V0V-5V+5V0V-5V+5V0V-5VTime-slice shown in diagram123Charge Transfer in a CCD 2.123+5V+5V+5VTime-slice shown i123+5V0V-5V+5V0V-5V+5V0V-5V123Charge Transfer in a CCD 3.123+5V+5V+5V123Charge Transfe

35、r123+5V0V-5V+5V0V-5V+5V0V-5V123Charge Transfer in a CCD 4.123+5V+5V+5V123Charge Transfer123+5V0V-5V+5V0V-5V+5V0V-5V123Charge Transfer in a CCD 5.123+5V+5V+5V123Charge Transfer123+5V0V-5V+5V0V-5V+5V0V-5V123Charge Transfer in a CCD 6.123+5V+5V+5V123Charge Transfer123+5V0V-5V+5V0V-5V+5V0V-5V123Charge T

36、ransfer in a CCD 7.Charge packet from subsequent pixel entersfrom left as first pixel exits to the right.123+5V+5V+5V123Charge Transfer123+5V0V-5V+5V0V-5V+5V0V-5V123Charge Transfer in a CCD 8.123+5V+5V+5V123Charge TransferOn-Chip Amplifier 1.ODOSRDRSWOutput NodeOutput TransistorReset TransistorSummi

37、ngWell+5V0V-5V+10V0VRSW-end of serial registerVoutVoutThe on-chip amplifier measures each charge packet as it pops out the end of the serial register.The measurement process begins with a resetof the reset node. This removes the charge remaining from the previous pixel. The resetnode is in fact a ti

38、ny capacitance ( 0.1pF)RD and OD are held at constant voltages(The graphs above show the signal waveforms)On-Chip Amplifier 1.ODOSRDRSWOOn-Chip Amplifier 2.ODOSRDRSWOutput NodeOutput TransistorReset TransistorSummingWell+5V0V-5V+10V0VRSW-end of serial registerVoutVoutThe charge is then transferred o

39、nto the Summing Well. Vout is now at the Reference levelThere is now a wait of up to a few tens of microseconds while external circuitry measuresthis reference level.On-Chip Amplifier 2.ODOSRDRSWOOn-Chip Amplifier 3.ODOSRDRSWOutput NodeOutput TransistorReset TransistorSummingWell+5V0V-5V+10V0VRSW-en

40、d of serial registerVoutVoutThis action is known as the charge dumpThe voltage step in Vout is as much as several mV for each electron contained in the charge packet.The charge is then transferred onto the output node. Vout now steps down to the Signal levelOn-Chip Amplifier 3.ODOSRDRSWOOn-Chip Ampl

41、ifier 4.ODOSRDRSWOutput NodeOutput TransistorReset TransistorSummingWell+5V0V-5V+10V0VRSW-end of serial registerVoutVoutVout is now sampled by external circuitry for up to a few tens of microseconds. The sample level - reference level will be proportional to the size of the input charge packet.On-Ch

42、ip Amplifier 4.ODOSRDRSWO2、電荷耦合器件的特性參數(shù)2.1 電荷轉(zhuǎn)移效率和轉(zhuǎn)移損失率N個電極轉(zhuǎn)移后所剩余的電量為2、電荷耦合器件的特性參數(shù)2.1 電荷轉(zhuǎn)移效率和轉(zhuǎn)移損失率N2.2 驅(qū)動頻率驅(qū)動頻率的下限 在信號電荷的轉(zhuǎn)移過程中，為了避免由于熱激發(fā)少數(shù)載流子而對注入信號電荷的干擾，注入電荷從一個電極轉(zhuǎn)移到另一個電極所用時間t必須小于少數(shù)載流子的平均壽命，對于二相來講，周期為T 載流子的平均壽命與器件的工作溫度有關(guān)，工作溫度越高，熱激發(fā)的少數(shù)載流子平均壽命越短，驅(qū)動頻率的下限越高2.2 驅(qū)動頻率驅(qū)動頻率的下限 在信號電荷的轉(zhuǎn)移過驅(qū)動頻率的上限 驅(qū)動頻率升高時，驅(qū)動脈沖驅(qū)使電

43、荷從一個電極轉(zhuǎn)移到另一個電極的時間t應(yīng)大于從一個電極轉(zhuǎn)移到另一個電極的固有時間，才能保證電荷的完全轉(zhuǎn)移，否則信號電荷跟不上驅(qū)動脈沖的變化，將會使轉(zhuǎn)移效率大大下降。電荷轉(zhuǎn)移的快慢與載流子的遷移率、電極長度、襯底雜質(zhì)的濃度和溫度等因素有關(guān)。驅(qū)動頻率的上限 驅(qū)動頻率升高時，驅(qū)動脈沖驅(qū)使電荷3 電荷耦合攝像器件 3.1、CCD攝像原理 CCD攝像器件可分為線列和面陣兩大類。以線列CCD為例說明攝像原理。 CCD線列圖象器件由光敏區(qū)、轉(zhuǎn)移柵、CCD移位寄存器、電荷注入、信號讀出電路等幾個部分組成。如圖所示是一個N個光敏元的線列CCD 3 電荷耦合攝像器件 3.1、CCD攝像原理 NN-1N-2321光敏

44、區(qū)轉(zhuǎn)移區(qū)CCD1 2電荷進(jìn)入1電荷從2進(jìn)入T31 2G0SPshRGVRDVODT2T3T1CRL加R脈沖注：對雙路輸出，另一路的電荷從2進(jìn)入T3（同一個）轉(zhuǎn)移區(qū)移位轉(zhuǎn)移柵(遮光)光敏單元轉(zhuǎn)移柵入射光NN-1N-2321光敏區(qū)轉(zhuǎn)移區(qū)CCD1 2電荷進(jìn)入1 CCD攝像過程可歸納為如圖所示的五個環(huán)節(jié) 積分轉(zhuǎn)移傳輸輸出計數(shù)工作波形如圖所示。 21RVoutPtt1 t2 t3 t4轉(zhuǎn)移準(zhǔn)備轉(zhuǎn)移結(jié)束有效積分時間（即SH）轉(zhuǎn)移 CCD攝像過程可歸納為如圖所示的五個環(huán)節(jié) 積分轉(zhuǎn)移傳輸輸出2） 轉(zhuǎn)移 就是將N個光信號電荷包并行轉(zhuǎn)移到所對應(yīng)的各位CCD中，t處于高電平。3）傳輸 N個信號電荷在二相脈沖1 、2

45、驅(qū)動下依次沿CCD串行輸出。4）計數(shù) 計數(shù)器用來記錄驅(qū)動周期的個數(shù)。通常計數(shù)器預(yù)置值定為N+m, m為過驅(qū)動次數(shù)。 1） 積分 在有效積分時間里，光柵P處于高電平， 每個光敏元下形成勢阱，光生電子被積累到勢阱中，形成一個電信號“圖象”。各個環(huán)節(jié)分述如下：2） 轉(zhuǎn)移 就是將N個光信號電荷包并行轉(zhuǎn)移到所對應(yīng)的各位3.2、幾種常用的CCD驅(qū)動方法CCD驅(qū)動時序產(chǎn)生方法多種多樣，常用的方法有：這種方法用數(shù)字門電路及時序電路搭成CCD驅(qū)動時序電路。一般由振蕩器、單穩(wěn)態(tài)觸發(fā)器、計數(shù)器等組成。可用標(biāo)準(zhǔn)邏輯器件搭成或可編程邏輯器件制成。特點(diǎn)是驅(qū)動頻率高，但邏輯設(shè)計比較復(fù)雜。 a 直接數(shù)字電路驅(qū)動方法 b.可編

46、程邏輯器件CPLD驅(qū)動頻率和積分時間可以調(diào)節(jié)3.2、幾種常用的CCD驅(qū)動方法CCD驅(qū)動時序產(chǎn)生方法多種多c 單片機(jī)驅(qū)動方法 單片機(jī)產(chǎn)生CCD驅(qū)動時序的方法，主要依靠程序編制，直接由單片機(jī)I/O口輸出驅(qū)動時序信號。時序信號是由程序指令間的延時產(chǎn)生。這種方法的特點(diǎn)是調(diào)節(jié)時序靈活方便、編程簡單，但通常具有驅(qū)動頻率低的缺點(diǎn)。如果使用指令周期很短單片機(jī)（高速單片機(jī)），則可以克服這一缺點(diǎn)。 在EPROM中事先存放驅(qū)動CCD的所有時序信號數(shù)據(jù)，并由計數(shù)電路產(chǎn)生EPROM的地址使之輸出相應(yīng)的驅(qū)動時序。這種方法結(jié)構(gòu)簡明，與單片機(jī)驅(qū)動方法相似。 d EPROM驅(qū)動方法c 單片機(jī)驅(qū)動方法 單片機(jī)產(chǎn)生CCD驅(qū)動時序e 專用IC驅(qū)動方法 利用專用集成電路產(chǎn)生CCD驅(qū)動時序，集成度高、功能強(qiáng)、使用方便。在大批量生產(chǎn)中，驅(qū)動攝像機(jī)等視頻領(lǐng)域首選此法，但在工業(yè)測量中又