Mark Itzler. i t li

Transcription

1 Geiger mode APD Cameras for Single Photon 3D LIDAR Imaging Mark Itzler PrincetonLightwave Inc. i t li

2 Geiger mode APD attributes Et Extremely sensitive to a single photon Lower power lasers Longer distance Highlyefficient useof photons 2 Highly scalable based on semiconductor wafers y Large format arrays of avalanche photodiodes (APDs) High area coverage rates usingmany pixels in parallel Single photon detection can spread power over more pixels

3 Sensitivity to single photons GmAPD pixels need ~100X fewer photons vs. linear APDs PLI GmAPD cameras optimized for 1064 nm or 1550 nm sources System flexibility in how to use extremely sensitivity pixels Longer rangewith same source e.g., higher altitude collections for airborne LiDAR Geiger Same range with weaker source e.g., diode lasers for automotive LiDAR 3 Single flash for larger # of detectors e.g., larger format arrays for highly parallel collections Linear

4 New paradigm with GmAPD arrays Inherently digital i data collection Single time of flight value per pixel per frame (but not fundamental limitation) Coincidence processing with several frames highly effective noise filtering High rate data collection ~100, frames per sec with kilo pixel frames Msample/sec Highly automated off line processing (with support from Moore s Law) Temporal averaging to create analog intensity High resolution data collection Spatial averaging to create analog intensity Flexibility with big data sets 4

5 Geiger mode today and tomorrow Commercial lgmapd cameras Next gen GmAPD APDtechnology PLI 32 x 32 = 1024 pixels 186,000 frames per second ~200 Msamples/second PLI 128 x 32 = 4096 pixels 92,000 frames per second ~400 Msamples/second 4.0 Miniaturization >5X: 4 x 4 x 4 2 x 2 x 3 Flexibility: free running pixels ~900 Msamples/second for 32x32 New async camera product in 2016 Larger formats (MIT Lincoln Lab) 256 x 64 deployed 256 x 128 and 256 x 256 fabricated MIT/LL 256 x 64 InP GmAPD FPA PLI GmAPD camera

6 Prospects for new LiDAR architectures Hybrid LiDAR combining Geiger mode and linear receivers Overlapping IR Geiger mode + green linear waveform resolved LiDARs High resolution i map of water surface using 1064 nm Geiger mode Gi LiDAR Correct for sea surface beam steering where single spot 532 nm penetrates water Potential for synergistic benefits usingbothtechniques techniques lasers Data courtesy of Grady Tuell, GTRI 7.5 mm IR point spacing 6 Co-aligned green and IR beams IR maps sea surface topography green beam IR beam IR receiver PLI 32x32 GmAPD camera Normal vectors computed for green beam footprint Guida, Nicholas, A New technique for 3D Modeling of Water Surfaces Using a Geiger Mode Receiver, Masters Thesis, School of Electrical and Computer Engineering, Georgia Institute of Technology, August 2015

7 7 Summary for GmAPDs Single photon sensitive for lower power, longer ranges Highly efficient use of photons Highly scalable to large format parallel LiDAR arrays High area coverage rates with large # of pixels Measure lower power per pixel with single photon sensitivity Field proven in DoD applications Operational deployment by MIT/LL, Northrop Grumman, other DoD Active PLI design in programs for targeting, autonomous flight, mapping Commercial LiDAR opportunities are comparable to DoD opps Harris IntelliEarth th overview from Mark kromano Visit PLI at Exhibit Booth #1!

8 BACK UP SLIDE 8

9 APD operating modes: Linear and Geiger Linear mode APD analog response ~10,000 electrical carriers detection threshold electrical noise Linear mode gain ~10 20 need photons strong weak single pulse pulse photon Geiger mode APD digital response detection threshold individual photons electrical noise 9 Can detect 1 photon (although can t tell how many)