BENEFITS OF USING A VERY HIGH CONTRAST VisIR PROJECTOR for NIGHT VISION TRAINING

Transcription

1 BENEFITS OF USING A VERY HIGH CONTRAST VisIR PROJECTOR for NIGHT VISION TRAINING Dr. Axel Krause, Sven Ziebart ILA Berlin 2018,

2 Agenda Requirements to a projector in a simulation system Contrast of a double modulation projector Benefits of a high contrast projector in simulation Direct night vision goggles stimulation Data input types Summary 2

3 Agenda 1 Requirements to a projector in a simulation system 2 Contrast of a double modulation projector 3 Benefits of a high contrast projector in simulation 4 Direct night vision goggles stimulation 5 Data input types 6 Summary 3

4 Requirements to a projector in a vision system Performance Image quality Resolution Color aberration Brightness Contrast Color gamut Night vision goggles stimulation More criteria Total cost of ownership Durability and Stability Maintenance Size Weight 4

5 Velvet Simulation Installations Application System type Number of channels Eurofighter (Germany) Full Mission Simulator Cockpit Trainer Transall / C-160 Collimator Tornado (Germany, US location) Full Mission Simulator 30 US-Navy LSO Trainer X Daimler Simulator 3 5

6 Agenda Requirements to a projector in a simulation system Contrast of a double modulation projector Benefits of a high contrast projector in simulation Direct night vision goggles stimulation Data input types Summary 6

7 Full on / off contrast Contrast Ratio of the intensity of a full white image to the intensity of a full black image The contrast determines the lowest projectable intensity. 7

8 Gamma curve reproduction and the contrast of a projector 1.E+00 1.E-01 1.E-02 Intensity versus Gray value Intensity 1.E-03 1.E-04 1.E-05 1.E-06 1.E Gray value Intensity Projector Contrast 2000 : 1 Projector Contrast : 1 Logarithmic scale Correct represantation of lowest gray levels requires a high contrast projector 8

9 DMD Digital Micromirror Device Illustration of 2 landed mirrors Top down view of landed mirrors 0.9 WQXGA DMD Pixel size 7.56 µm dlp.ti.com 9

10 Principle of double modulation Illumination DMD Imaging DMD Stray light of the illumination DMD Stray light Off state of the imaging DMD Light Lens Resulting contrast Contrast of the illumination DMD * Contrast of the imaging DMD On state 10

11 Agenda Requirements to a projector in a simulation system Contrast of a double modulation projector Benefits of a high contrast projector in simulation Direct night vision goggles stimulation Data input types Summary 11

12 Velvet Gamma curve reproduction 1.E+00 1.E-01 1.E-02 Velvet - Intensity versus Grayscale Intensity 1.E-03 1.E-04 1.E-05 1.E-06 1.E Gray value Intensity True 10 bit resolution gamma curve reproduction allows pure electronic blending in dome application 12

13 Blending performance for a bit depth of 8 bit Blend zone of four projectors with a bit depth of 8 bit after blending for input grey level 7 Contrast enhancement was applied to make the artefact clearly visible. 13

14 Blending performance for a bit depth of 10 bit Blend zone of four projectors with a bit depth of 10 bit after blending for input grey level 7 Contrast enhancement using same parameters as before was applied. 14

15 Agenda Requirements to a projector in a simulation system Contrast of a double modulation projector Benefits of a high contrast projector in simulation Direct night vision goggles stimulation Data input types Summary 15

16 Sensitivity of night vision goggles Night vision goggle light amplification systems especially sensitive in the infrared wavelength region Source: TOWARDS REPEATABLE, DETERMINISTIC NVG STIMULATION By Charles J. Lloyd, Steven G. Nigus, Brian K. Ford Conference proceedings Image

17 Wave length bands 400 nm 700 nm Standard wave length bands in projection: Red Green Blue Additional wavelength band Infrared Lamp emits light in the visible and infrared band. 17

18 Color wheel for visible image Color wheel Lamp Integrator 18

19 Visible Image Color Filter Transmitted Color 0 ms 16.7 ms Visible Mode: 4 Subframes in 16.7 ms (60 Hz input rate) 19

20 Color wheel and shutter wheel for visible and infrared image Color wheel Shutter wheel Lamp Integrator 20

21 Visible and infrared image Color Filter 1 Transmitted color Color Filter 2 Transmitted color 21

22 Visible and infrared image 0 ms 8.3 ms 16.7 ms Visible and infrared image 8.3 ms RGBRGB 8.3 ms Infrared 22

23 Green and Infrared Spectrum Spectral Power Green Segment 1.2 Relative infrared intensity Pe [a.u.] 4 3 Relative intensity Wavelength [nm] Wavelength [nm] A very high contrast projector allows to generate an infrared image directly stimulating night vision goggles. 23

24 Application for Night vision goggles training Blended infrared image of two projectors 24

25 Agenda Requirements to a projector in a simulation system Contrast of a double modulation projector Benefits of a high contrast projector in simulation Direct night vision goggles stimulation Data input types Summary 25

26 Dual Input Channel Data Path Visible Input Data Infrared Input Data RGB Image Infrared Image n RP, n GP, n BP = n R, n G, n B n INFRAREDP = n INFRARED Data modification is not needed. 26

27 Single Input Channel Data Path Input data RGB Image Data modification n RP, n GP, n BP = f 1 (n R, n G, n B ) Data modification Infrared Image n INFRAREDP = f 2 (n R, n G, n B ) Clone Mode Same input data for RGB and Infrared Data modification is possible for the RGB and the infrared image. 27

28 Dual channel versus one channel input mode Dual Channel Input Single Channel Input The image content is solely determined by the settings of the image generator in the visible and in the infrared channel. The dual channel input mode requires an additional IG channel. Accurate presentation of the infrared image. The image content is determined by the settings of the image generator and the settings of the projector. A single IG channel is used. Approximate presentation of the infrared image. 28

29 Agenda Requirements to a projector in a simulation system Contrast of a double modulation projector Benefits of a high contrast projector in simulation Direct night vision goggles stimulation Data input types Summary 29

30 BENEFITS OF USING A VERY HIGH CONTRAST VisIR PROJECTOR for NIGHT VISION TRAINING The contrast of 1 : allows True gray ramp representation Pure electronic, maskless blending Direct stimulation of night vision goggles. The visible and infrared images are generated by one projector. Input data can be dual channel or single channel. 30

31 Modified ZEISS Velvet projector with unique modularity IR module (as upgrade option for night vision) a c Light unit module (interchangeable, irrespective of light source) Powerboard module b 31

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33 Gamma curve reproduction and the contrast of a projector Intensity versus Gray value Intensity Gray value Intensity Projector Contrast 2000 : 1 Projector Contrast : 1 Linear scale Gamma curve for γ = 2.2 (standard value in simulation industry) 33