1412A Technical Manual 012407 0

8/8/2019 1412A Technical Manual 012407 0

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TECHNICAL MANUAL FOR

DVC-1412A CAMERAS

Manual Number: 86-1412-05

Release Date: January 24, 2007

DVC Company

10200 Highway 290 West

Austin, Texas 78736

Phone: (512) 301-9564

Fax: (512) 288-2961

E-Mail: [email protected]

WWW: http://www.dvcco.com


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TABLE OF CONTENTS

TABLE OF CONTENTS ........................................................................................................................................2

1 INTRODUCTION ...............................................................................................................................................7

2 INITIAL INSPECTION......................................................................................................................................82.1 UNPACKINGANDRECEIVING ................................................................................................................82.2 OPTIONALITEMS.......................................................................................................................................92.3 CAMERAPOWERSUPPLY........................................................................................................................9

2.3.1 INTERNATIONAL APPLICATIONS .....................................................................................................9

3 MAINTENANCE...............................................................................................................................................10

3.1 IMPORTANTWARRANTYINFORMATION..........................................................................................103.1.1 Intensified Cameras .............................................................................................................................10 3.1.2 TE-Cooled Cameras ............................................................................................................................103.1.3 MultiSpectral Cameras ........................................................................................................................10 3.1.4 Standard Cameras ...............................................................................................................................11

3.2 CLEANING GUIDELINES ................................................................................................................................11

3.2.1 Cleaning the lens or optical assembly .................................................................................................113.2.2 Cleaning the infra-red filter (Standard and TE-Cooled Cameras).............. .......... ........... .......... ........113.2.3 Cleaning the intensifier front element (intensified cameras) .......... ........... .......... ........... .......... ..........123.2.4 Cleaning the Multispectral Camera optical components (Multispectral Cameras only) ....................12

3.3 INFRA-RED FILTER REMOVAL AND INSTALLATION ........................................................................................133.3.1 How to remove the IR filter..................................................................................................................13

4 CAMERA SPECIFICATIONS ........................................................................................................................16

4.1 OPTICAL ....................................................................................................................................................164.2 DIGITALVIDEOOUTPUT .......................................................................................................................17

4.2.1 12 Bit RS-422/RS-644 (LVDS / FireWire) ...........................................................................................174.3 1412AINTENSICAM.................................................................................................................................17.................................................................................................................................................................................17

4.4 CAMERACONTROL.................................................................................................................................184.5 ELECTRICAL.............................................................................................................................................184.6 MECHANICAL: STANDARD LVDS/FIREWIRE/CAMERALINK CAMERAS ........... .......... ........... ....184.7 MECHANICAL : COOLED CAMERAS ...................................................................................................184.8 MECHANICAL : INTENSICAM...............................................................................................................18

5 CAMERA FUNCTIONAL DESCRIPTION...................................................................................................20

5.1 CCDOPERATIONANDVIDEOPROCESSING......................................................................................205.1.1 CCD Sensor.........................................................................................................................................205.1.2 Video Processing .................................................................................................................................215.1.3 Video Digitization................................................................................................................................215.1.4 Timing..................................................................................................................................................21

5.2 DIGITALI/O...............................................................................................................................................22

5.2.1 LVDS Version: TTL to LVDS Drivers..................................................................................................225.2.2 FireWire Version .................................................................................................................................225.2.3 CameraLink Version ............................................................................................................................22

6 MODES OF OPERATION...............................................................................................................................23

6.1 NORMALMODE .......................................................................................................................................236.2 HIGHSPEEDSHUTTER............................................................................................................................24

6.2.1 Setting The Exposure Duration............................................................................................................246.2.2 Strobe...................................................................................................................................................246.2.3 Reset & Shutter....................................................................................................................................25


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6.2.4 Reset Modes.........................................................................................................................................25 6.3 NFRAMEINTEGRATION........................................................................................................................27

6.3.1 Reset Operation in N-Frame Integration Mode...................................................................................286.4 ULT:ULTRA-LONG-TERMEXPOSURE ................................................................................................28

6.4.1 Dark Current Reduction in Ultra Long Exposure mode.......... ........... .......... ........... .......... ........... ......286.5 PULSEDRIVENEXPOSURE....................................................................................................................286.6 BINNING ....................................................................................................................................................29

6.6.1 Binning and Shutter:............................................................................................................................31 6.6.2 Binning and Bayer Pattern Color Filter Arrays ........... .......... ........... ........... .......... ........... .......... ........31

6.7 SUB-ARRAY/REGION OF INTEREST (ROI)...................................................................................................326.7.1 Functional Description........................................................................................................................326.7.2 Advantages...........................................................................................................................................336.7.3 Disadvantages......................................................................................................................................336.7.4 What can be done to overcome this disadvantage? ......... ........... .......... ........... ........... .......... ........... ....336.7.5 What applications should ROI be used for? ........................................................................................336.7.6 ROI Commands....................................................................................................................................33

6.8 SLOWSCAN ..............................................................................................................................................346.9 INTENSICAM-1412A ................................................................................................................................35

6.9.1 Introduction .........................................................................................................................................356.9.2 Functional Description........................................................................................................................356.9.3 Spectral Response................................................................................................................................366.9.4 Intensicam & DVCView....................................................................................................................37

6.10 MULTI-SPECTRALOPTION....................................................................................................................386.10.1 Optical Considerations........................................................................................................................386.10.2 Software considerations.......................................................................................................................386.10.3 Module Removal & Change of Filters .................................................................................................41

7 APPLICATION NOTES...................................................................................................................................49

7.1 BAYERFILTERDECODINGALGORITHM ...........................................................................................497.1.1 Introduction .........................................................................................................................................497.1.2 Color Pixel Processing........................................................................................................................497.1.3 White Balance......................................................................................................................................497.1.4 Gamma Correction ..............................................................................................................................51

7.1.5 Color Coding .......................................................................................................................................517.1.6 Suggested Algorithm............................................................................................................................51

8 SERIAL COMMAND INTERFACE DEFINITION FOR DVC-1412A CAMERAS (LVDS ANDCAMERALINK CAMERAS)...................................................................................................................................52

8.1 INTRODUCTION.......................................................................................................................................528.2 COMMUNICATIONPROTOCOL.............................................................................................................528.3 CAMERACONTROLS ..............................................................................................................................52

8.3.1 Camera ID ...........................................................................................................................................528.3.2 Gain .....................................................................................................................................................538.3.3 Offset....................................................................................................................................................538.3.4 EST.......................................................................................................................................................538.3.5 FSH......................................................................................................................................................53

8.3.6 FSL.......................................................................................................................................................538.3.7 Exposure ..............................................................................................................................................538.3.8 Mode Summary ....................................................................................................................................54

SPECIALCOMMANDS.........................................................................................................................................558.3.9 Intensifier Control ...............................................................................................................................56 8.3.10 Notes on Intensifier Operation.............................................................................................................568.3.11 Notes on Wheel Commands .................................................................................................................58

8.4 COMMANDSUMMARY...........................................................................................................................60

9 INFORMATION AND SUPPORT RESOURCES .........................................................................................61


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10 APPENDIX ........................................................................................................................................................62

10.1 APPENDIXA:MECHANICALDIMENSIONSDIAGRAM ....................................................................6210.2 APPENDIXC:DVC-1412ACAMERACONNECTORS...........................................................................69

10.2.1 Auxiliary Connector.............................................................................................................................69 10.2.2 Connector Overview ............................................................................................................................71

11

WARRANTY AND AFTER-SALES SERVICE.............................................................................................72

12 COPYRIGHT INFORMATION......................................................................................................................73


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LIST OF FIGURES

Figure 2.3-1: Bottom view of power supply showing voltage selection switch (115V)................................................9Figure 2.3-2: Bottom view of power supply showing voltage selection switch (220V)................................................9Figure 2.3-3: IEC line cord with Euro-style plug .......... ........... .......... ........... .......... ........... .......... ........... .......... ........... .9

Figure 2.3-4: IEC line cord with UK-style plug .......... ........... .......... ........... .......... ........... ........... .......... ........... .......... ...9Figure 4.1-1: Monochrome camera spectral response .......... ........... .......... ........... .......... ........... .......... ........... .......... ...16Figure 4.1-2: IR Filter Characteristics .........................................................................................................................16Figure 4.3-1: Spectral curve for Intensicam ................................................................................................................17Figure 5.1-1: Bayer pattern color filter array...............................................................................................................20Figure 6.1-1: Timing diagram--normal mode..............................................................................................................23Figure 6.2-1: Timing diagram--shutter mode (HNL & HDL) .......... ........... .......... ........... ........... .......... ........... .......... .24Figure 6.2-2: Timing diagramHDO Mode...............................................................................................................26Figure 6.2-3: HDL mode .............................................................................................................................................27Figure 6.3-1: Timing diagram--long exposure.............................................................................................................28Figure 6.5-1: Pulse driven integration mode, showing long/short exposure with minimum latency...........................29Figure 6.6-1: Bin 2x2 example ....................................................................................................................................30Figure 6.9-1: Intensicam spectral response..................................................................................................................36

Figure 6.10-1: Cooled (left) and non-cooled (right) multi-spectral cameras. .......... ........... .......... ........... .......... ..........38Figure 6.10-2: Maximum Lens Depth .........................................................................................................................39Figure 7.1-1: Bayer Pattern CFA.................................................................................................................................49Figure 0-1: Luminous Gain versus IGN Argument ........... .......... ........... .......... ........... .......... ........... .......... ........... ......56Figure 10.1-1: 1412A with LVDS connector ..............................................................................................................62Figure 10.1-2: 1412A with CameraLink connector.....................................................................................................63Figure 10.1-3: 1412A Camera with 1394 Connector...................................................................................................64Figure 10.1-4: 1412A TE Cooler Camera (LVDS model shown) .......... .......... ........... .......... ........... .......... ........... ......65Figure 10.1-5: Intensicam-1412A Image Intensifier Camera (LVDS shown).............................................................66Figure 10.1-6: 1412-Multispectral Wheel Non-Cooled Camera (LVDS shown) ......... ........... ........... .......... ........... ....67Figure 10.1-7: 1412-Multispectral Wheel Cooled Camera (FireWire shown) .......... ........... .......... ........... .......... ........68


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LIST OF TABLES

Table 6.6-1: Binning commands..................................................................................................................................30Table 6.8-1: Slow-scan mode commands ....................................................................................................................34Table 10.2-1: Camera connector information..............................................................................................................71

Table 10.2-2: Power supply connector pinout .......... .......... ........... .......... ........... ........... .......... ........... .......... ........... ....71


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1 INTRODUCTION

DVC Company, based in Austin, Texas, is a manufacturer of cost-effective, high performance digital videocameras. We thank you for purchasing from the DVC-1412A product series.

This series of cameras is based on the premise that precise image processing applications demand mega-pixel cameras that are optimized for the performance available from todays leading-edge CCDs, whilemaintaining an acceptable price to performance ratio.

The 2/3 interline Sony ICX285 CCD imager used in the DVC-1412A cameras has a 1392(H) x 1040(V)

progressively-scanned image format and has a pixel size of 6.45m x 6.45m. The CCD sensor has aparticularly high QE in the blue-green region of the spectrum resulting in higher sensitivity for mostapplications.

The DVC-1412A series of cameras includes non-cooled, cooled, intensified, and multi-spectral versions.Furthermore, a choice of I/O options is available: LVDS, CameraLink, or FireWire. Standard camerafeatures include high-speed shuttering, long-term integration, pulse driven integration, and gain/offsetcontrol. All DVC cameras come with a standard 2-year warranty and use industry-standard C-mountlenses.

This camera series also includes Intensicam, which utilizes a gated, Gen III image intensifier, fiber-optically coupled to the CCD.

With the LVDS version, the 10 frames/s video data is provided in a 12 bit parallel, differential LVDSformat, which is "plug-and-play" compatible with industry-standard image processors. The digital data,pixel clock, enable line, and enable frame signals are accessible via the DB-44 connector.

The CameraLink version transmits 10 frames/s, 12-bit data over an industry standard MDR-26 interface toany CameraLink compatible frame grabber.

In the FireWire version of the camera, the LVDS output is replaced by an industry standard 1394Ainterface. The camera provides 12-bit data at 10 frames/s when used with any OHCI-compliant FireWireinterface card.

Computer-based control of gain and offset is provided to "tune" the dynamic range of the camera to theapplication. This provides an optimum match between the dynamic range and sensitivity of the camera andthe requirements of the application.

The CCD is physically mounted in the cavity of a high-precision opto-mechanical plate for excellentmechanical stability. An adjustable C-mount coupling allows critical system focusing adjustments. In-camera digitization using the stable CCD pixel clock eliminates pixel jitter, improves repeatability, andenables sub-pixel accuracy in image processing applications.

DVCView, a Windows GUI software package is supplied with the camera, allowing image viewing andcontrol of all camera operations. Five user programmable, single-click software buttons allow the userto customize the camera to the imaging application.

This manual applies to all of the DVC-1412A cameras.


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2 INITIAL INSPECTION

2.1 UNPACKING AND RECEIVING

These items were thoroughly tested and carefully packed in the factory. Upon acceptance by the

carrier, they assume responsibility for its safe arrival. Should you receive your DVC shipment in adamaged condition, apparent or concealed, a claim for damage must be made to the carrier. To

return the product to the factory for service, please contact the DVC Customer Service Department

at (512)-301-9564 for a Return Material Authorization (RMA) Number. Returns are not acceptedwithout an RMA number.

If visual inspection shows damage upon receipt of this shipment, it must be noted on the freight bill

or express receipt, and the notation signed by the carrier's agent. Failure to do this can result in the

carrier refusing to honor the claim.

When the damage is not apparent until the unit is unpacked, a claim for concealed damage must be

made to the carrier immediately. Keep all cartons and packing materials. Since shipping damage is

the carrier's responsibility, the carrier will instruct you on filing the concealed-damage claim.


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2.2 OPTIONAL ITEMS

The following items are optional items and may be ordered from authorized dealers of DVC. They

are not typically supplied with each Camera.

1. Lenses and/or other optical elements2. Third party image analysis software.

2.3 CAMERA POWER SUPPLY

DVC provides a power supply for use with the DVC-1412A camera. The electrical and optical

specifications of the camera are guaranteed only when used with DVC supplied accessories.

NOTE: The power is sealed for the safety of the operator. There are no user-serviceable parts

inside the power supply, and it should not be opened since there are dangerously high voltages

within. The warranty will be voided if the power supply is tampered with or opened.

2.3.1 INTERNATIONAL APPLICATIONS

Figure 2.3-1: Bottom view of power supply showing voltage

selection switch (115V)

Figure 2.3-2: Bottom view of power supply showing voltage

selection switch (220V)

Figure 2.3-3: IEC line cord with Euro-style plug Figure 2.3-4: IEC line cord with UK-style plug


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3 MAINTENANCE

3.1 IMPORTANT WARRANTY INFORMATION

There are no user-serviceable parts inside the camera. Removing the rear cover of

the camera without express authorization from DVC Company may void the camerawarranty.

This camera contains sensitive devices that can be damaged by static discharge. Use appropriatestatic control methods when handling the camera. Avoid contact with connector pins when cables

and plugs are removed.

Depending on the model, your DVC camera may contain a glass, infra-red blocking filter to

prevent infra-red light from reaching the CCD sensor. This filter is located in the lens mountingring and it also protects the CCD sensor faceplate or other optical components from contamination

and direct contact.

DVC cameras are manufactured in a clean environment, and each camera is thoroughly tested prior

to shipping to ensure that it meets our stringent specifications for cleanliness and quality. However,accumulation of dust on the camera optical surfaces in the customer application is not covered by

warranty.

To ensure optimum image quality with any DVC camera, do not remove the protective lens-mount

cap until ready to mount the camera on the application. If the camera is removed from the

application, immediately replace the cap. Doing so will keep dust and other contaminants from

accumulating on the optical surfaces. In addition, please note the following model-specific

guidelines.

3.1.1 Intensified CamerasThe image intensifier is a delicate electronic device and can be permanently impaired by exposure

to excessive light. Damage to the intensifier due to overexposure is not covered under warranty.Never run an intensified camera if it is not attached to an optical system, and always check

illumination levels carefully before activating the intensifier and increasing the intensifier gain.

Finally, follow cleaning guidelines outlined in section 3.2.3

3.1.2 TE-Cooled CamerasThe DVC Thermoelectrically-cooled cameras contain the CCD in a sealed, gas-filled chamber

having an anti-reflective glass window. Do not, under any circumstances, loosen or remove the

inner glass window from a cooled camera. Doing so will void the warranty. If it is suspected that

the seal has been broken or if the window breaks, do not apply power to the camera. Moisture may

have been introduced, and cooling in the presence of moisture will cause condensation and frost on

the CCD. Call DVC Customer Service. Otherwise, follow the cleaning guidelines in section 3.2.2

3.1.3 MultiSpectral CamerasUnless specified otherwise, DVC multispectral cameras do not utilize a separate infrared filter.

When the lens is removed, it is possible to contact the filter surfaces and the filter wheel assembly.

Use precaution when changing filters and follow the installation and cleaning procedure in section

7.10.3.4.

Because the filter wheel takes up a portion of the fixed distance between the C-Mount mounting

surface and the image plane, care should be taken to ensure that the rear element of any lens to be


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used does not protrude into the filter cavity, which may cause damage to the lens, filter, or filter

wheel. See section 7.10 in this manual for more details.

3.1.4 Standard CamerasWhile the lens mounting ring and locking flange allow the user some lens back-focus adjustment,

complete removal of the ring will expose the CCD faceplate and will likely cause debris to

accumulate on its surface. Extreme care should be taken to avoid completely removing the lens

mounting ring and exposing the CCD faceplate unless absolutely necessary. Fingerprints or

other evidence of contact with the CCD faceplate may void the warranty.

3.2 Cleaning Guidelines

Frequent lens changes, especially without careful attention to contaminants, can allow debris to

accumulate on the infra-red blocking filter and lens surfaces. Therefore, DVC Company provides

the following guidelines for cleaning those components.

3.2.1 Cleaning the lens or optical assemblyPlease follow the manufacturers recommendations for cleaning. DVC Company is not responsiblefor any damage caused to the lens or optical assembly caused by customer cleaning or misuse.

3.2.2 Cleaning the infra-red filter (Standard and TE-Cooled Cameras)The infra-red filter is visible when the lens is removed, mounted inside the lens mounting

ring.

3.2.2.1 What must I do before cleaning the infra-red filter?Do not remove the filter from the camera.

First, remove the lens and carefully examine the filter in a clean location under a

strong, direct light. Try to determine if the contaminants are a few dust particles,

oily smudge (such as fingerprints) or both.

3.2.2.2 What if the contamination is only a few dust particles?Use a CLEAN, DRY (preferably brand-new), camel hair lens cleaning brush (such

as those used by photographers) to gently wipe the particles off of the filter.

3.2.2.3 What if the contamination includes a smudge?The filter is a high-quality, coated optical component and should be treated with

extreme care. Scratches, chemical contamination, or other damage due to

improper cleaning may void the warranty.

Remove the camera from the optical assembly and bring the camera to aclean, dry location where it is safe to use flammable solvents (please see

caution below)

Carefully loosen the lens mount lock ring using the supplied DVC lockring wrench.

Orient the camera so that the lens mount is pointing downward andcarefully unscrew the lens mounting ring and integral filter.

Place the camera face down on a clean, dry surface to prevent particlesfrom accumulating on the CCD faceplate.


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Once the filter is removed, Use a CLEAN, DRY (preferably brand-new),camel hair lens cleaning brush (such as those used by photographers) to

gently wipe the particles off of the filter.

Re-examine the filter after removing the dust. If a smudge is still visible,

proceed by dipping a clean, lint-free cotton swab in ethyl or isopropylalcohol. The swab should be saturated, but not dripping.

Carefully draw the swab once across the surface, then rotate the swab 180degrees to expose the fresh surface and draw it across the filter surface

again. Be careful not to pool alcohol on the glass surface.

Re-examine once again and repeat the process once, if necessary..

Caution: ethyl and isopropyl alcohols are highly flammable! Do not use near

extreme heat, arcing electrical equipment (such as space heaters) or openflame! Use only with proper ventilation. Follow all safety instructions

provided by the manufacturer of the alcohol product.

If contamination continues to be a problem, please call DVC Customer Service for

assistance.

3.2.3 Cleaning the intensifier front element (intensified cameras)The intensifier front element is the glass plate visible when the lens is removed. As

always, dust accumulation can be reduced by minimizing removal of the camera

from the application and replacing the protective lens cap during those periods the

camera is removed.

3.2.3.1 What must I do before cleaning the intensifier front element?First, remove the lens and carefully examine the front element in a clean locationunder mild direct light (care must be taken not to expose the intensifier to strong

light). Try to determine if the contaminants are a few dust particles, oily smudge

(such as fingerprints) or both.

3.2.3.2 What if the contamination is only a few dust particles?Use a CLEAN, DRY (preferably brand-new), camel hair lens cleaning brush (such

as those used by photographers) to gently wipe the particles off of the surface.

3.2.3.3 What if the contamination includes a smudge?DVC strongly recommends returning the camera to the factory for professionalcleaning to avoid damage to the camera. Scratches, chemical contamination, or

other damage due to improper cleaning may void the camera warranty.

If contamination continues to be a problem, please call DVC Customer Service for

assistance.

3.2.4 Cleaning the Multispectral Camera optical components (Multispectral Cameras only)Follow instructions for removal of filters in section 7.10 and clean filters

individually using the instructions for cleaning the infra-red filter in section 3.2.2

above


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3.3 Infra-red filter removal and installation

The DVC1412A series cameras have very high quantum efficiency in the red and near-

infra-red regions of the spectrum, making them suitable for near-infra-red imaging

applications. In such applications, it may be necessary to remove the infra-red filter. It is

important to note that removal of the IR filter may allow debris to collect on the CCD

faceplate. Please use every precaution to avoid contact with the CCD faceplate and to keepthe camera securely mounted to the optical system or capped when not in use.

3.3.1 How to remove the IR filterCaution: This procedure will cause the focus calibration to be lost. Readjustment of the lens back

focus will be required after reassembly

1. Loosen the lens mount lock ring with the wrench supplied by DVC

2. Unscrew the lens mount/filter assembly ring from the camera body and remove the lock ringfrom the lens mount ring

3. Hold the lens cap with the pins sticking upward in one hand

4. Lower the lens filter assembly on to the pins with the other hand


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5. Hold the lens cap and rotate the lens ring anti-clockwise and then remove the lens ring.

6. Remove the filter from the filter ring with lens tissue and store in a protective container

7. Replace the lens ring on to the filter ring and screw on clockwise

8. Remove the lens ring from the lens cap


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9. Screw the lock ring back onto the lens mount ring and screw both back onto the camera. Adjust

focus by loosening the lock ring and rotating the lens mount ring to adjust the lens-to-CCD distance.

To re-install the IR filter or other filters, reverse the above procedure.


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4 CAMERA SPECIFICATIONS

4.1 OPTICAL

Sensitivity @ 1890K

(measured without IR filter)

Monochrome: 0.022fc for full-scale, 0dB gain,

1/10 sec exposure.

Pixel size and format 6.45m(H)X 6.45m(V); interline format

Spectral Response See Figures 4.1-1, 4.1-2,

Figure 4.1-1: Monochrome camera spectral response

0

10

20

30

40

50

60

70

80

90

100

400 500 600 700 800 900 1000 1100

Wavelength

%Transmittance

Figure 4.1-2: IR Filter Characteristics


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4.2 DIGITAL VIDEO OUTPUT

4.2.1 12 Bit RS-422/RS-644 (LVDS / FireWire)Readout Rate 18 MHz, 9 MHz,

(user selectable via software)

Resolution/Frame Rate

(Binning: Monochrome model only)

1392 x 1040 at 10.2 f/s (1 x 1)1392 x 520 at 20 f/s (1 x 2)

696 x 520 at 20 f/s (2 x 2)

348 x 260 at 39 f/s (4 x 4)

174 x 130 at 68 f/s (8 x8)

Signal to noise >65 dB, at min. gain

Gamma 1.0 (linear)

4.3 1412A INTENSICAM

(The data shown below represents the standard photocathode response. Extended blue

and special Gen IV versions are also available).

QE > 35% Quantum Efficiency from 500 to 800 nmSensitivity 1X10

-8fc Sensitivity (faceplate) @ 2854K, 10fps

Photocathode GaAs photocathode, std spectral response 450 to

900 nm

Intensifier life > 10,000 hrs @ 10-5

fc or lower

Geometric Distortion < 1%

Resolution 64 1p/mm

Gating 50 ns to 98 ms

Figure 4.3-1: Spectral curve for Intensicam


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4.4 CAMERA CONTROL

RS-232C,DVC-ViewInterface Software module, standard

Gain control 30 dB

Offset control (black) 0% to 6 % in 16 steps

High speed shutter 93 s to 98 ms

Long Exposure control 98 ms to 15 min in two ranges

4.5 ELECTRICAL

Timing Progressive scan

Power Supply Voltages &

Current requirements 15 V DC each @ 250 mA

+ 5 V DC @ 250 mA

Clock Rate 18 MHz derived from internal crystal oscillator

4.6 MECHANICAL: STANDARD LVDS/FIREWIRE/CAMERALINKCAMERAS

Weight (without lens) 12 ozs. (340 grams)

Temperature limits (operating) -10C to 50C

Temperature limits (storage) -30C to 70C

Dimensions 3.25 (H) X 3.25 (W) X 1.73 (L)

Lens mount Industry-standard C- mount

Camera mount 2 X - 20 threaded holes for top/bottom mount

Digital Video Connector

LVDS: DB-44, female connector

(See Appendix C)

FireWire: Standard 1394A connector

CameraLink: Standard MDR-26, 26-pin connector

Power Supply ConnectorLVDS: DB-9, Male connector (see Appendix C)

Firewire: Standard 1394A connector

4.7 MECHANICAL : COOLED CAMERASWeight (without lens) 27.9 ounces (792 grams)



Dimensions 3.90" (H) X 3.90" (W) X 2.80" (L)

Lens mount Industry Standard C-Mount


Digital Video Connector

LVDS:DB-44, female connector (See Appendix C)


CameraLink: Standard 26-pin connector

Power Supply ConnectorLVDS: DB-9, Male connector (see Appendix C)


4.8 MECHANICAL : INTENSICAMWeight (without lens) 22.0 ounces (624 grams)




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Dimensions 3.25 (H) X 3.25 (W) X 3.20 (L)

Lens mount Industry Standard C-Mount


Digital Video Connector DB-44, female connector (See Appendix C)

Power Supply Connector DB-9, Male connector (see Appendix C)

NOTE: See Appendix A for dimensioned mechanical diagrams.


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5 CAMERA FUNCTIONAL DESCRIPTION

5.1 CCD OPERATION AND VIDEO PROCESSING

5.1.1 CCD SensorLight from the scene is brought into focus at the imaging plane of the CCD. A 1mm thick,

removable infrared blocking filter can be used to attenuate infrared light at the CCD focal plane.

The IR blocking filter is attached to the c-mount adapter ring. For non-IR multi-spectral imaging

applications with the DVC-1412AC Mount Adapter without an IR filter is available.

The following functions take place within the CCD:

5.1.1.1 IntegrationDuring the integration period, photon-induced charge is integrated in the active charge site wells.

The amount of charge that is integrated in each active charge site well is proportional to the

illumination received at each active charge site on the CCD. In the case of the color camera, each

charge site has a Red, Green or Blue color filter over the field, designating it as a Red, Green or

Blue pixel. The filter pattern that is used is referred to as a Bayer pattern, which is shown below:

Figure 5.1-1: Bayer pattern color filter array

5.1.1.2 Charge TransferDuring the Vertical blanking interval, the charge that was integrated in each active charge siteduring the previous exposure (normally 1/10 sec, or one frame) is shifted to an adjacent opaque

storage charge site. In the figure below, active charge sites are designated by the letter I for

integration and the opaque storage charge sites are designated by the letter S for storage.

G B G B ..

R G R G ..

G B G B ..

R G R G ..

: : : : ::


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S I S I S I S I SS I S I S I S I SS I S I S I S I SS I S I S I S I SS I S I S I S I SS I S I S I S I S

S ICharge transfer(once per frame)

S I S I S I S I SS I S I S I S I SS I S I S I S I SS I S I S I S I SS I S I S I S I SS I S I S I S I S

H-line transferCharge detection node

Horizontal shift register

1392 columns

1040 rows

Figure 5.1-2: Block diagram of CCD

5.1.1.3 ReadoutIn the following adjacent frame, the charges are transferred vertically, one line at a time, from the

storage charge sites of the CCD to an on-chip horizontal shift register and then sequentially to the

detection node where they are made available as signal voltages. NOTE: While one frame is being

read out from the opaque pixels, the next frame is being integrated in the active charge sites of the

CCD.

5.1.2 Video ProcessingThe low-level video signal voltage from the CCD is clamped (for black reference) and fed througha high-speed CDS correlated double sampling CDS amplifier. The CDS process is required to

remove noise from the video signal. The video signal is then amplified in the next stage, which has

voltage-controlled-gain and voltage-controlled-offset.

5.1.3 Video DigitizationThe video signal output from the video processor is fed to a 12-bit analog-to-digital converter.

5.1.4 TimingThis logic block on the CCD and video board performs the following functions:

Generation of CCD timing signals Generation of Video & handshaking timing signals

Asynchronous Reset function

Mode control function

Exposure control function


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5.2 DIGITAL I/O

5.2.1 LVDS Version: TTL to LVDS DriversThe digital image data is latched and converted to an LVDS format (on the I/O board) for

transmission as a balanced, differential signal along the cable which consists of shielded twisted

pairs.

5.2.1.1 RS232 InterfaceThis is made up of a microprocessor-based circuit, which communicates via an on-board UART

with the serial port of a PC.

5.2.2 FireWire Version5.2.2.1 Isochronous DataThe digital video data is latched and converted to an isochronous IEEE 1394 A (FireWire) formatfor transmission as a serial data stream on a standard FireWire interface cable.

5.2.2.2 Asynchronous DataCamera control commands from the host PC are sent via the FireWire interface cable in the form ofasynchronous data. The data is received and translated into internal camera control signals that are

used to set gain, offset exposure etc. in a variety of camera modes.

5.2.3 CameraLink VersionThe digital image data is latched and converted to an CameraLink format (on the CameraLink

board) for transmission as a balanced, differential signal along the cable which consists of shielded

twisted pairs. Command and control data (including asynchronous reset signals, under framegrabber/software control) are also sent in accordance with the CameraLink specification.

NOTE: The command set for LVDS & CameraLink versions of the camera are identical.


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6 MODES OF OPERATION

6.1 NORMAL MODE

In each mode description, the serial mode commands (CameraLink and LVDS versions only)are shown. Please refer to the serial mode commands details in Section 9.4.

NRR: Normal mode with reset

NOR: Normal without reset

In the normal mode of operation, the following signals are used to synchronize a digital frame

grabber to the camera:

Pixel Clock: Periodic 18 MHz, square wave output which is synchronous with digitized pixel data.

Enable Frame: Periodic 10 Hz (frame rate) output; the rising edge signifies the start of a valid

frame and the falling edge signifies the end of a valid frame

Enable Line: Periodic 10.7 KHz (line rate) output; the rising edge signifies the start of a valid lineand the falling edge signifies the end of a valid line.

The Horizontal and Vertical Drive signals are usually outputs generated by the camera.

In the timing diagram show below, charge transfer from the active (imaging) charge sites to

adjacent (opaque) storage sites takes place at the beginning of a frame. In this process, all the

charge that was accumulated in the imaging charge sites during the previous frame is transferred to

the opaque storage sites.

Charge transfer

Line count 1 2 3 4 5 6 7 8 9 10 11 12 13 1047104810491050 10511052 1 2 3 4 5 6 7 ....

Horizontal DriveVertical Drive

Enable Line

Enable Frame

Pixel Clock

V I D E OCCD Output BLK BLK BLK 1 2 .... .... .... .... 1040 BLK BLK BLK

Exposure = 1/10 sec

Figure 6.1-1: Timing diagram--normal mode

Every horizontal line during the next frame, one line of the charge matrix in the opaque storage

sites is shifted vertically into a horizontal shift register. The horizontal shift register is clocked out,

one pixel at a time, on to a charge detection node that converts it to a voltage, which can be

sampled and digitized.


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6.2 HIGH SPEED SHUTTER

HDO: High speed shutter with discharge (one-shot)

HNL: High speed shutter without discharge

When one of the high-speed shutter modes is selected, the duration of exposure is set as an integral

number of horizontal-line-periods. In the shutter modes, the duration of exposure can be set from 1-

to-1045 horizontal lines, in 1-horizontal-line-period (approx. 90 sec) increments.

6.2.1 Setting The Exposure DurationThe Camera exposure settings are set using the EXP command, e.g. EXP 0A5 sets the exposure to

0x0A6 number of lines in all the shutter modes (HDO, HDL, HNL). The duration of exposure in

the high-speed shutter modes is from 1 through 1052 horizontal line periods, represented by an 11-

bit control word.

High-speed shutter mode without discharge (HNL): In this mode asynchronous resets are ignored.

This mode is designed for use in applications in which the electronic shutter is used primarily as a

means of light level control, i.e. as an electronic "iris" in cases where there is too much light in thefield of view. This is usually done to prevent saturation of the CCD with a full frame or 1/10sec

exposure. The normal sequence of timing (see fig. 7.2-1) is followed and there are no interruptions

of the Enable_frame, Enable_line and Pixel Clock signals.

In the example below, exposure is set to 1/500sec; this translates to 21 horizontal-line-periods (21 x

93 sec = 1/500sec). In order to achieve this exposure, the CCD must be exposed for 21 line

periods out of the total of 1045 line periods in the frame. Since the CCD has to continuouslyintegrate charge, the 21 line-period exposure is obtained by "dumping" the charge every line for the

first 1020 line periods, and then stopping the "dumping" action for the last 21 line-periods. At the

end of this active 21 line exposure period, the charges are transferred to the storage matrix

followed by readout. This is shown graphically in the timing diagram below.

Charge transfer

Line count 1 2 3 4 .... .... .... .... 1031 1032 1033 1034 .... .... 1050 1051 1052 1 2 3 4 .... .... .... .... 1031 1032 1033 1034 .... .... 1050 1051 1052

Charge dump

Strobe outputExposure = 21 lines Exposure = 21 lines

Figure 6.2-1: Timing diagram--shutter mode (HNL & HDL)

6.2.2 StrobeIn many applications, objects in the field of view can be moving too rapidly to be properly imaged

under normal conditions. A combination of the high-speed shutter and a strobe may be used tostop motion. It is often desired to synchronize the strobe action with the camera exposure. For this

purpose, a STROBE output pulse is generated within the camera. The STROBE output pulse

allows an external strobe light to be turned on during the exposure period. Since the duration of the

exposure is a user-programmable setting, the start-time (relative to the vertical timing of the

camera) and the duration of the STROBE output pulse also vary, depending upon the shutter

setting.


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The strobe output pulse is generated to coincide with the exposure period. It is asserted (rising

edge) after the last "charge dump" pulse in each frame. It goes low at the next CCD readout pulse

(see above diagram). The strobe light can be activated at any time during the HIGH duration of the

strobe output pulse.

6.2.3 Reset & ShutterIn some applications, it is necessary to synchronize the camera to an external event. In order toallow flexibility, two camera RESET methods are provided: TTL and differential.

NOTE: Frame grabbers have the ability to control the differential input (CC1+, CC1-) or

(INPUT1+, INPUT1-) of the camera. This is facilitated by connecting them via two wires within

the camera-framegrabber interface cable to differential frame grabber outputs that are driven by a

General Purpose register bit that is to be controlled by host software. The TTL input (VRST_INT)

is usually NOT connected via the camera-framegrabber interface cable. Therefore, in most

applications, the VRST_INT signal floats HIGH,enabling resets from the framegrabber (under

control of the host software). In some cases, however, users may want to feed a TTL reset signal

directly to the camera, e.g. from an optical detector in an inspection application. In this case, the

user must ensure that the differential input (INPUT1 or CC1) is either driven HIGH or allowed to

float HIGH.

Within the camera, these two signals are logically AND-ed together and the resulting RESETsignal is used to reset the counters within the camera-timing chip. If either the TTL (VRST_INT

signal) or the differential (INPUT1 or CC1) is unused it floats HIGH due to internal pull-ups. The

other signal may be pulled "LOW" to cause a reset to the camera.

In cameras that have an auxiliary input connection, the VRST_INT (TTL) input is available as one

of the pins. In some applications, this input can be used to reset the camera directly instead of

generating resets from the frame grabber.

In the LVDS version, these inputs are called VRST_INT (TTL-pin39 of the DB44 connector) and

INPUT1(differential LVDS-pins [34,35] of the DB-44 connector). The default level for both thesesignals is logic "HIGH".

In the CameraLink version, based on the CameraLink specifications, the CC1 signal allows the

CameraLink compliant PCI board to reset the camera under software control. In addition, a 6-pin-

mini-DIN auxiliary connector is provided, that includes a TTL reset input called VRST_INT.

6.2.4 Reset ModesIn the HDO and HDL shutter modes, an asynchronous falling edge on the VRST_INT (TTL) or

CC1/INPUT1 (differential) input of the camera is used to synchronize the exposure period of the

camera to the outside world (the rising edge is not significant, however, the LOW duration should

last at least 1sec). Since the falling edge is truly asynchronous, in most instances it would havethe effect of interrupting the readout of a previously exposed frame from the storage area elements

of the CCD; a residual charge from the previous exposure therefore may exist on the storage area

elements. This charge must be removed from the storage area by a discharge process before the

next charge transfer takes place.


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6.2.4.1 One Shot high speed shutter with discharge (HDO, HDX)This mode is also referred to as the "one-shot" or "snapshot" mode. In this mode, the camera acts

like a snapshot digital camera. The camera outputs no frames (and no Enable_Frame signals) until

a reset signal is received (see above section related to reset signals). Once a reset signal is received,

the camera immediately performs one-and-only-one exposure (with the duration determined by the

previously set EXP command) resulting in one-and-only-one valid Enable_Frame signal. NOTE:

there is no latency or delay between the falling edge of reset and the start of the exposure.

READOUT READOUT

EXPOSURE

User defined

exposure period

1 frame =

1/12sec

EXPOSURE

NO VIDEO

VRST_INT (TTL) or INPUT1 (LVDS)

CHARGE TRANSFER (Internal Signal)

STROBE OUT (TTL)

Pixel Clock and Enable_Line (run continuously)

ENABLE_FRAME1/10 s 1/10 s

Figure 6.2-2: Timing diagramHDO Mode

HDX mode offers exposure times longer than the HDO limit of roughly 100ms, though the

exposure granularity is in five-line increments rather than one. In a typical frame grabber based

system, the displayed image is updated only when the reset is generated; until then, the previouslycaptured image (resulting from the previous reset) is displayed. Therefore this mode is referred to

as the asynchronous "snapshot" mode.

NOTE: The frame grabber should be capable of sustaining long periods of time without receiving

an Enable-Frame signal.

The exposure is set, as in all shutter modes, via the serial EXP command. In HDO mode, the

argument is 11 bits, and in HDX it is12 bit. For example, EXP 014 in HDO will set up the exposure

to be equivalent to 21 lines of exposure (Hex"014" = Decimal 20); since one-line-period is 93sec,

this is the same as 21 x 93sec = 0.002sec or 1/500sec. In HDX mode, it is five times that value.

6.2.4.2 High speed shutter with discharge (HDL)If an asynchronous reset occurs while the camera is in this mode, the residual charge in the storage

area from a previous exposure is flushed out (discharged) by a sequence of vertical channel transfer

pulses. This period lasts for 6.8msec (see timing diagram below). NOTE: the discharge pulses

affect only the storage area; the "charge dump" pulses that are required to clear the imaging area

are generated immediately after the discharge within the 6.8mSec period. This is followed by the

exposure period and then the readout of the integrated charge. As shown below in the timing

diagram, the normal sequence of the Enable_frame signal is interrupted by the asynchronous reset

input; It is forced LOW by the falling edge of the reset signal and remains low until the discharge


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and exposure periods are completed (6.8mS + user_defined_shutter_exposure). The rising edge of

the Enable_frame signal signifies the start of the readout process of the synchronized frame.

NOTE: the Enable_line and Pixel Clock signals are un-interrupted by the reset signal and run

continuously.

NOTE: If the exposure period is greater than 80 lines, then a special condition exists, which

allows a concurrent discharge and exposure, eliminating the taking period between the falling edgeof reset and the start of exposure that exists in cases where the exposure period is less than 80 lines.

After the synchronized frame is readout, normal shutter operation resumes until the next falling

edge of the asynchronous reset is received.

Figure 6.2-3: HDL mode

6.3 N FRAME INTEGRATION

NFR: "N" frame integration (low speed shutter)

When the low-speed shutter mode (or N Frame Integration mode) is selected, the duration ofexposure is set as an integral number of frames. For the DVC-1412A camera, the duration of

exposure can be set from 1-to-1024 frames, in 1-frame increments. NOTE: since one frame is

1/10sec or 100msec, the range of control is from 1/10sec to 102 sec.

If the exposure is set to, for example, 1 second ; this translates to 10 second-periods (10 x 1/10sec =

1sec). In order to achieve this exposure, the CCD must be exposed for 10 frame periods between

transfers. Since EXP 000 corresponds to a 1-frame exposure, a 10 frame exposure will result from

an EXP 009, setting.

In order to maintain synchronization with a frame grabber, the pixel clock and enable line signals

are un-interrupted during exposure and subsequent readout. The enable frame signal, however, is

set "low" during exposure and goes "high" during readout to signify that the accumulated frame is

VRST_INT (TTL) or INPUT1 (LVDS)

Enable_frame

Pixel Clock and Enable_Line (run continuously)

STROBE OUT (TTL)

READOUT

EXPOSURE

READOUT

EXPOSURE

READOUT

EXPOSURE

READOUT

EXPOSURE

READOUT

EXPOSURE

EXPOSURE

Discharg

e

Discharge duration = 6.8ms

User defined

exposure period

1 frame =

1/10 sec


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being read out and may be captured by the frame grabber. This is shown graphically in the timing

diagram below.



FRAME 1 FRAME 2 FRAME 3 FRM N-1 FRAME N READOUTVideo Blanked

Integrated

Image

FRAME 1 FRAME 2 FRAME 3 FRM N-1 FRAME N READOUTVideo Blanked

Integrated

Image

Reset operation in the "N" Frame Integration Mode

ENABLE LINE & PIXEL CLOCK (RUN CONTINUOUSLY)ENABLE FRAME

INTEGRATION PERIOD = N * 1/10 sec INTEGRATION PERIOD = N * 1/10 sec

Transfer Pulse (Internal Signal)

VRST_INT (TTL) or INOUT1 (RS-422)

Figure 6.3-1: Timing diagram--long exposure

6.3.1 Reset Operation in N-Frame Integration ModeDuring the N-Frame integration mode, a falling edge of the VRST_INT (TTL) or the

CC1/INPUT1(LVDS) resets the camera and initiates a new N-frame exposure (as shown above).

6.4 ULT: ULTRA-LONG-TERM EXPOSURE

This mode is identical to the NFR mode, except that there is a x120 multiplier in the EXP

argument. This means that an EXP argument of N will have the effect of setting up an integration

of (N+1) x120 frames, e.g.: N=3 would result in an exposure of (3+1)X120 frames = 480 framesor 48 sec.

6.4.1 Dark Current Reduction in Ultra Long Exposure modeThe DVC 1412A Cameras incorporate a hardware dark current reduction technique in

ULT mode, frequently called diode glow reduction. Diode glow refers to areas in the

image that have elevated dark current due to active circuitry on the CCD chip, detectable

only in very long exposures. The DVC 1412A cameras employ a proprietary technique

that results in a 10x reduction of diode glow in the ultra long exposure mode.

Software developers may choose to design a single exposure slider bar for long exposures.

When the exposure is less than eg. 60 sec, the NFR mode may be used, with an increment of 1

frame time = 1/10 sec. For longer exposures, the ULT mode is invoked with an increment of 120

frames = 12 sec. The transition between NFR mode and ULT mode may be transparent to the user;

the only real difference between the ULT and NFR mode from the users perspective is the

granularity of control.

6.5 PULSE DRIVEN EXPOSURE

PDX: Pulse driven exposure (external)

PDI: Pulse driven exposure (internal, one-shot)

PDP: Pulse driven exposure (internal, periodic)


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When the Pulse Driven Exposure mode is selected, the duration of exposure is set by the user via

the LOW duration of an externally generated pulse. A falling edge of the pulse clears the imager

and initiates exposure, a subsequent rising edge terminates exposure, resets the vertical counter

within the camera and initiates readout of the acquired frame.

This pulse signal may be TTL (VRST_INT) or differential(CC1+ or CC1-) or (INPUT1 + &

INPUT1-); these two inputs are logically AND-ed within the camera, therefore one of them shouldnormally be HIGH if the other one is to be used. There are no prescribed limits to the LOW

duration; therefore this mode affords the user the most flexibility in terms of controlling the

duration and the instant of exposure. For example, application software can be written to directly

drive the camera between long and short exposures without any latency; some applicationdevelopers choose to use the PDX mode as the sole camera mode, since this can control long and

short exposure easily by controlling a single signal. The max rep rate of the driving pulse in the

1412A is limited to 1/(frame period + exp).

In order to maintain synchronization with a frame grabber, the pixel clock and enable line signals

are un-interrupted during exposure and subsequent readout. The enable frame signal, however, is

set "low" during exposure and goes "high" only during readout to signify that the accumulated

frame is being read out and may be captured by the frame grabber. This is shown graphically in the

timing diagram below.



Pulse Driven Integration Mode

ENABLE FRAME

INTEGRATION PERIOD

VRST_INT (TTL) or INOUT1 (LVDS)

1/10 sec 1/10 sec

INTEGRATION

PERIOD

Figure 6.5-1: Pulse driven integration mode, showing long/short exposure with minimum latency

6.6 BINNING

Binning is a feature of the camera that allows the user to trade-off camera resolution in favor of

frame rate and sensitivity. When one of the binning modes is selected, a selected number of

contiguous pixels is treated as one super-pixel. This is illustrated below, shown in the bin 2x2

case. By means of transferring two lines into the horizontal shift register, pixels are summed

vertically. These vertically summed pixels are then clocked out to the detection mode without theusual intervening reset gate signal.


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Table 6.6-1: Binning commands

Shift Register

H-shift c lock

Reset Gate

Shift Register

H-shift c lock

Reset Gate

Shift Register

H-shift clock

Reset Gate

Shift Register

CCD Array

CCD Array

CCD Array

CCD Array

Normal mode (1x1) vs. Binning mode (2x2)

Charge

Detection

Node

Charge

Detection

Node

Charge

Detection

Node

Charge

Detection

Node

Shift Register

H-shift c lock

Reset Gate

Shift Register

H-shift c lock

Reset Gate

Shift Register

Shift Register

CCD Array

CCD Array

CCD Array

CCD Array

Charge

Detection

Node

Charge

Detection

Node

Charge

Detection

Node

Charge

Detection

Node

Figure 6.6-1: Bin 2x2 example

Command Code Description Frame Size Frame Rate

BIN 11 1 x 1 binning 1392(H) x 1040(V) 10.2f/sec (normal mode)

BIN 21 2 x 1 binning 1392(H) x 520 (V) 20f/sec

BIN 22 2 x 2 binning 696(H) x 520(V) 20f/sec

BIN 44 4 x 4 binning 348(H) x 260(V) 39f/secBIN 88 8 x 8 binning 174(H) x 130(V) 68f/sec


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In the above figure, the pixels marked by the heavy border, are read out as one super-pixel value.

The binning mode of the camera is set via the BIN command. There are five valid arguments to this

command {11, 21, 22, 44, 88}.

6.6.1 Binning and Shutter:The following table is provided as a guide for calculating the shutter mode exposure values that

apply in the different binning modes.

The shutter setting for binning modes needs to be shifted with an offset, in order to get the desiredamount of exposure:

mode no exposure 1_line 2_line max line

1x1 0 1 2 1043

2x2 520 521 522 1043

2x2 520 521 522 1043

4x4 780 781 782 1043

8x8 910 911 912 1043

6.6.2 Binning and Bayer Pattern Color Filter ArraysWhen binning is performed within the CCD, e.g. in the BIN 2x2 mode, the charge from a 4-pixel

quad made up of 2-horizontal and 2-vertical pixels is collected into one CCD horiz-shift-register

element. The charge value that is read out therefore corresponds to a summation of the 4-pixel

quad.

P11 + P12

+

P21 + P22

---------------

1-data-value

---------------

In this mode, the user trades off resolution for frame rate and sensitivity.

In a Bayer-filter color camera, the 2x2 binning mechanism described above creates a quad

summation which results in R+G+G+B value.

R11 + G12

+G21 + B22

---------------

1-data-value

---------------

This R+G+G+B value does not represent any meaningful color information; however, it may be

used as a luminance value. Application developers may use BIN 2x2, BIN 4x4 or BIN 8x8 modes

(in a color camera) to create a fast monochrome image during focusing, fast object/image


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manipulation in the field-of-view etc. and then revert to a full-resolution color image after

determining an image of interest.

6.7 Sub-array / Region of Interest (ROI )

In many applications, users wish to designate a particular Region of Interest (ROI) within the entire

image.

The ROI feature of the DVC-1412A allows the definition of a band of pixel-rows that are selected

for readout. The CCD is then fast-scanned through the un-selected areas, allowing for a faster

overall frame rate of only the selected area. Since the faster frame rate is created by the selection of

fewer pixel-rows, only the vertical Y parameter needs to be set within the camera.

The application software may also allow the designation of unwanted columns (for example, by

allowing the user to draw a ROI box around the selected region. In that case, the application may

blank the unwanted columns for a convenient presentation to the user. However, the de-selection

of columns from readout has no effect on the frame rate.

6.7.1 Functional DescriptionUnder normal conditions, every pixel of the CCD array is read out to create an image frame fordisplay. The camera images, transfers, and read-outs. With the 1412A, there is a 1/10 second

exposure, occurring concurrently with 1/10 second read-out. Thus, while readout N-1 takes place,

exposure N is occurring simultaneously

Normal Exposure EXPN EXPN+1 EXPN+L

Readout RDTN-1 RDTN RDTN+1

Exposure EXPN EXPN+1 EXPN+LSub-

array /

ROI

(16XN)

Readout FAST

RDTN-1NORMAL

FAST

RDTN RDTN+1

ROI 512 X N 256 X N 64 X N 16 X NTable

Frames/sec 19 32 70 100

100 mSec (10 f/s)

10 ms (100 f/s)


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unwanted - fast scan

wantedwanted

unwanted - fast scan

trimmed in display with software

[normal scan][normal scan]

6.7.2 AdvantagesROI allows faster frame rate without compromising spatial resolution. The benefit of ROI is that

fewer lines are scanned instead of scanning all lines of the CCD. Thus, a higher number of frames

per second are achieved. Instead of getting 10 frames per second, the user could view the selected

pixels at full-resolution at a faster frame rate.

6.7.3 DisadvantagesThe downside of ROI is that as one reduces the ROI, the frame duration is lowered leading to lower

exposures per frame, causing less image brightness. For example, if the exposure time went from

1/10 second to 1/100 of second, the image would be a significantly lower duration ofexposure/frame.

6.7.4 What can be done to overcome this disadvantage?One can sacrifice the lack of brightness or can compensate for brightness in another way. This can

be done by making the lamp brighter in a microscope or by opening-up the iris of a lens. Thus,

ROI is especially advantageous where one has control of the light

6.7.5 What applications should ROI be used for?In applications such as bright field microscopy and single molecule tracking, the user can select an

area of interest and improve the effective frame rate. The Intensicam-1412A is based on the 1412Aand is used for low-light images where the user wants speed.

6.7.6

ROI Commands

ROI {0,1} .. {OFF,ON}

BTY yyy .. Bottom Y coordinate; three digit Hex; should be divided by 2 TPY YYY ..

Top Y coordinate; three digit Hex

The Y coordinate starts from the first line to be read out and counts up to 1032. Due to its internal

implementation, BTY needs to be divided by 2. For example:


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ROI 1

TPY 100 (H100=>256)

BTY 100 (H100=>256*2=512)

Will set an ROI from pixel row 256 to pixel row 512

In the present implementation, ROI and BIN are mutually exclusive commands. This will bechanged in later versions.

6.8 SLOW SCAN

Slow scan: The read noise of a CCD can be significantly affected by the readout rate. Some users

wish to improve the read noise by slow-scanning the CCD. This is provided in the camera by

means of a clock multiplexer scheme; the user selects which one of the two) clocks is to be used as

the pixel clock.

NOTE: This selection affects all the internal clocks, since the entire timing logic runs on the

selected clock. Therefore, all exposure values etc. will be scaled accordingly.

The slow-scan mode of the camera is set via the SLW command. There are two valid arguments to

this command {01, 02}.

Command Code Description Frame Rate Clock

SLW 01 Fast pixel clock divided by 1 10f/sec 18 MHz

SLW 02 Fast pixel clock divided by 2 5f/sec 9 MHz

Table 6.8-1: Slow-scan mode commands


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6.9 INTENSICAM-1412A

6.9.1 IntroductionThe Intensicam-1412A is a special version of a 1412A camera in which a gated Gen III image

intensifier is fiber-optically bonded to the front surface of the CCD. Due to the high luminous gain

of the Intensifier tube, every incident photon generates thousands of electrons within the tube.

Even under very low-light conditions, this results in a live image on the phosphor of the Intensifier,

which is viewable by the CCD.

6.9.2 Functional Description

Camera

Power

Supply

Calibration Control

Micro-

processor

To Host

Computer

I/O BoardCCD Board

Gain DAC

Pulse Generator

CCD

Fiber Optic

Module

Intensifier Control Board

CCD Board

1 format C-

mount lens

adaptor

Intensifier

Power

Supply

Gated

Gen III

Image

Intensifier


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Fiber-optic module: This is used to couple the image that is generated on the phosphor of the image

intensifier to the CCD. Since the optical format of the image intensifier is 1 and that of the CCD

is 2/3, a taper is used for the reduction.

High voltage power supply: This is used to generate the voltages that are necessary for theperformance of the image intensifier.

Intensifier control board: This board interfaces between the camera I/O board and the high-voltage

power supply. A serial interface is used between the I/O board and the controller chipset.

NOTE: Over-exposure can cause permanent damage to the Intensifier tube internal to

Intensicam.

6.9.3 Spectral ResponseStandard and enhanced coatings are available to provide different spectral characteristics (see

Figure 7.8.1). The phosphor of the intensifier (which is fiber-optically coupled to the CCD) emits

in the blue-green part of the spectrum, which is well matched to the peak-response of the CCD.

The spectral response for the standard intensifier (and the extended blue version) are shown below;

enhanced coatings are available upon request.

Figure 6.9-1: Intensicam spectral response


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6.9.4 Intensicam & DVCView1) In DVCView, there is an "Intensify" check box on the control panel that controls the

intensifier. As long as this box is not checked, the Intensifier is gated OFF (to protect thecamera). Although the camera is connected (and a frames/sec counter is visible in the LHS

of the viewing window), the image will remain black.

2) The user must click on the check box to turn the Intensifier on. {NOTE: Over-exposurecan cause permanent damage to the Intensifier tube that is part of the Intensicam.Damage due to overexposure is not covered under the warranty. It is the user's

responsibility to ensure that the light settings of the microscope or optics are appropriate

for use with this camera. If an overload is detected (in the form of an overexposed white

image), the user should IMMEDIATELY uncheck the box to turn OFF the Intensifier.

Then, after readjusting the optics, the process may be repeated until suitable viewing

conditions exist.

For further instructions on using DVCView, please refer to the DVCView User Manual,

available at the DVC website: www.dvcco.com


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6.10MULTI-SPECTRAL OPTION

Figure 6.10-1: Cooled (left) and non-cooled (right) multi-spectral cameras.

A module equipped with a four-position multi-spectral filter wheel is integrated within a modified

monochrome DVC-1412A camera housing (both TE-cooled and non-cooled versions are

available). The filter module can be supplied with high-quality CLEAR/IR-CUT, RED, GREEN,

BLUE optical filter elements or with special application set. It is designed such that the filter

elements can easily be removed and replaced with the users choice of standard 1 filters. The entire

module, comprising of the wheel, filters, motor and electronics can easily be removed from the

camera housing, to facilitate the use of different multispectral filter sets to match the users

applications. A tool is provided to facilitate the removal and replacement of filter elements on the

wheel.

The wheel is indexed to the "Home" position, which nominally coincides with the CLEAR/IR-CUT

optical filter. A serial command set is used to step the filter wheel through its four positions, which

place one of the four filter elements in the optical path of the CCD. Once a particular optical filter

is positioned in front of the CCD, the user may invoke any of the camera modes (discussed in this

manual) to set up parameters such as gain, offset, exposure and mode. This allows users to set up

sequential multi-spectral exposures to match the requirements of the application.

6.10.1 Optical ConsiderationsThe standard C-mount lens system specifies a fixed distance of 0.69 inches between the lens mount

reference surface and the image plane. Because the filter wheel assembly must utilize some of this

space between the lens and CCD, the distance between the lens mounting surface and the lens rear

element can be no greater than 0.18 inches, as shown in figure 7.10-2. Important: if this distance

is exceeded, the rear element of the lens will contact the filter wheel assembly and could causedamage.

6.10.2 Software considerationsIn R-G-B color applications, three individual color plane images are taken sequentially; these color

plane images are usually superimposed via software to create a high-resolution full-color image.

There are several factors involved to ensure high-quality images with such a sequential system:


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6.10.2.1 Image RegistrationThe three color planes should be precisely aligned; misregistration of the color planes will result in

image artifacts ranging from loss of resolution to misaligned edges. The camera should be securely

mounted during use to prevent misregistration.

6.10.2.2 Auto White BalanceIn order to make the white areas in the field of view appear to be white (R=G=B), most software

applications use a calibration scan, in which R, G and B images are obtained to determine the

relative strength of each component. Once the calibration data is obtained, software algorithms are

employed to determine the correct combination of gain/exposure for each color plane in order to

produce a white pixel at the appropriate location in the superimposed image.

Figure 6.10-2: Maximum Lens Depth


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6.10.3 Module Removal & Change of FiltersEstimated Time of Removal: 2-3 minutes

Materials Needed: 3/32" socket head drive, dry air bottle

Important Considerations: Use care not to put fingerprints on the filter surfaces. Wear rubber gloves while

performing this operation

Filters with holders & glass thickness up to 4mm are acceptable in 25 mm diameteraluminum frame

The housing that holds the filter should be 3.5mm - 4.5mm thickness and 25.4mm indiameter.

For RGB, the filter disk is numbered 1C, 2R, 3G, 4B (where C = Clear, R = Red, G =Green, B = Blue). The filters must be placed in this order

When the camera is turned on, it will set itself such that, position 1 is the default or homeposition in front of the lens


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6.10.3.1 Removing the Filter Wheel Module1) Remove the two 4/40" X 3/8" Allen-head screws which retain the module.

a. These screws are the only silver-colored screws on the camera.b. Use a 3/32" socket head drive to remove the screws.

2) Disengage the filter wheel module.a. Pull firmly to remove the module from the camera.b. There are no connectors to disengage. The module will simply slide out.


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6.10.3.2 Removing the Filter1) Using the filter-spring removal tool, grasp the tool with one hand, while holding the filter with

the opposite hand.

2) Align the tool on top of the filter spring.


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3) Push and turn the tool while compressing the spring, so that the tabs on the tool go underneaththe protrusions holding the filter spring. This process will disengage the filter. Rotate the tool

until both the spring tabs and the tool are clear of the protrusions.

4) Remove the tool. Use forceps or fine pliers to remove the spring.


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5) Place a clean surface lens paper where you want the filter to fall upon. Turn the module upside down. This will cause the filter to fall out.

6.10.3.3 Installing Filters1) Identify the filter surface with a lip. This surface should face the bottom of the wheel.


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2) Drop the filter into the slot.

3) Identify the spring surface with the dot protrusions. The dot should face the top.

4) Drop the spring into the slot above the filter.


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5) Using the filter-spring removal tool, compress the spring.Turn the tool until the dots line up. Remove the tool.


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6.10.3.4 Inserting the Filter Wheel Module in the Camera1) Clean the filter wheel with low pressure, dry air to remove any dust and contaminants. As with

any optical surfaces, blow at an angle to avoid driving particles directly into the surface at high

velocity. Use a clean, dry (preferably brand-new) camel-hair brush (like those used by

photographers) to gently remove any remaining particles.

2) Engage the module with the slots in the camera.

3) Slide the filter wheel module back into the camera. Push the module all the way in.

4) Install the two 4/40" X 3/8" Allen-head screws with a 3/22 socket head tool.


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7 APPLICATION NOTES

7.1 BAYER FILTER DECODING ALGORITHM

7.1.1 IntroductionThe following information is provided to assist software developers to create a high-resolution

color image from the digitized data that is provided by the DVC-1412C Camera.

1) The electronics within the camera are the same for the monochrome as well as for the R-G-B

version of the camera. For this reason, all the timing signals, including digitized video data, clock,

enable-line and enable-frame are the same for both cameras. Also, all modes of operation that are

described for the monochrome version of the camera apply to the R-G-B version. These modesinclude the electronic shutter modes, asynchronous reset mode, and pulse driven integration modes.

2) The color-filter-array (CFA) of the color imager follows the commonly used "Bayer pattern".

This pattern (shown below) is based on the premise that the human eye derives most of theluminance data from the green content of a scene; and it is the resolution of this luminance data

that is perceived as the "resolution" of an image. Therefore, by ensuring that more of the pixels are"green", a image of higher perceived resolution can be created--compared with an alternating R-G-

B color filter array with equal numbers of Red, Green and Blue pixels.

Figure 7.1-1: Bayer Pattern CFA

7.1.2 Color Pixel ProcessingThe following steps are required for processing the color pixels

7.1.3 White BalanceDepending on the "color temperature" of the light source, a white object may generate different

values for its R, G and B pixel values. For example, when the camera is pointed at a uniformly

diffused white object that fills the entire field of view, the resulting R, G and B values may form

the following matrix:

G B G B ..

R G R G ..

G B G B ..

R G R G ..

: : : : ::


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R=110, G=300, B=200 R=200, G=300, B=110(fluorescent lighting)(incandescent lighting)

Figure 7.1-2: Examples of Bayer Pattern values for fluorescent and incandescent light

Both cases require correction, because a white object should have R=G=B data values. The

simplest correction would involve "equalizing" the data - if the Green pixel values are kept

unchanged and the Red and Blue pixel values are multiplied by appropriate "gain" coefficients.

In the case of the "fluorescent lighting" example, Red Gain (Rg) should be 300/115 = 2.6 and Blue

Gain (Bg) should be 300/200 = 1.5

In the case of the "incandescent lighting" example, Rg (or Red Gain) should be 300/200 = 1.5 and

Bg should be 30/115 = 2.6

As shown in the above examples, the Rg and Bg coefficients depend on the type or the color

temperature of the illumination that is used. Therefore, a "white balance" operation is required each

time that the scene illumination or color temperature is changed.

The procedure for a white balance operation is as follows:

the software instructs the user to point the camera at a uniform white object e.g. asheet of white paper.

the software instructs the user to press the "white-balance " button.

the software examines the ratios G/R and G/B and determines the average value ofRg and Bg over a predetermined region. It is usually a good idea to keep the ratios

reasonably small.

the software then stores the computed average Rg and Bg values and uses them ascoefficients to generate color corrected Red and Blue pixel values from the "raw"

Red and Blue pixel values.

In some applications, it may be possible to store some frequently observed combinations of Rg and

Bg to simplify this operation. For example, if the camera is used under the same lighting conditionsat all times, the user should be able to perform the white balance operation once and then store theRg and Bg values. A typical software user interface might have three choices under Preset White

Balance options: "Typical Fluorescent", "Typical Incandescent" and "User Setting."

300 200 300 200 . .

110 300 110 300 . .

300 200 300 200 . .

110 300 110 3

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