Industrial Affiliates March 2nd, 2005 1

Ranging-Imaging Spectrometer

Brian A. KinderAdvisor: Dr. Eustace Dereniak

Optical Detection LabOptical Sciences CenterThe University of ArizonaTucson, Arizona 85721

Industrial Affiliates March 2nd, 2005 2

OUTLINE Overview of Detection Lab

Introduction to the concept of 4-D Imaging

Background-Hyperspectral and 3-D Imaging

Ranging-Imaging Spectrometer

Results and Conclusions

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Information in a Scene Spatial – Spectral – Polarization – Temporal

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Past and Current Work VIS-SWIR-MWIR Snapshot Spectrometers VIS (point)-SWIR (imaging) Spectropolarimeters Dual Band (SWIR-MWIR) Imaging Spectrometer LWIR Systems Algorithm work Ranging-Imaging Spectrometer (RIS)

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4-Dimensional Subset 3-D Spatial and Hyperspectral Data

Hyperspectral means that much smaller <>

xy

zz

yx

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Computed Tomographic Imaging Spectrometer (CTIS)

No moving parts and off-the-shelf optics Conventional Focal Plane

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Spectral Images

Panchromatic image in 0th order

Limited to one Octave

Limited Angle Tomography

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Test Images

Raw CTIS image

Reconstructed Image

Test Object

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CTIS Images

420

480

540

600

660

Spectral bandwidth: 420-720 nm in 10 nm steps

80 × 80 spatial sampling

Visible System

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Scannerless Range Imaging LADAR Developed by Sandia

National Labs

Heterodyne Technique 15 m range wrap

Measure Time of Flight R = ½ c*t

Conventional Focal Plane

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Capturing Range Data Transmitter and MCP Gain Waveforms

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Range Images

Phase Image Sequence

Reconstructed Range Image

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Concept

Combine two systems → x, y, z, and ! Use the same focal plane array Use established technology Eliminate registration issues Reduce the cost

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Ranging-Imaging Spectrometer LADAR operating at 857nm, removed narrowband filter CTIS operating from 600-900nm

CTIS

LADAR

Baffle

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0th order is 77 x 77 pixels

panchromatic image

Only portion where ranging is possible

RIS ImagesLaser only

Ambient only

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White Coffee cup Illumination sources

Laser pointer (647.25 nm) Laser Illuminator (857nm)

Spectral Results

Single pixel Spectra

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Spectral Results

Ambient Light

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Spectral Resolution642.636nm

623.566nmwith laser

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Range Results

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Range vs. Ambient Light Remove narrow band filter → Spectra Nomenclature

Laser Phase Sequence Ambient Phase Sequence

Laser – Ambient Laser only

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Error Correction Technique

Laser and Ambient data sequences Shift Laser data to zero Mean is linear → find laser only mean Find desired variance using mean-variance curve Multiply and add laser only mean back

)(*))(( 2

2

offonMeas

Desononc LLMeanLMeanLD

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Error Correction Results

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Conclusions Able to combine CTIS and SRI LADAR Able to obtain 3-D spatial and Hyperspectral

data on a single focal plane Develop a range correction technique Resolution

77 x 77 Spatial subtends 12.5 10nm spectral/tested 19.5nm 15cm range

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Acknowledgements Eustace Dereniak (Advisor), John Reagan,

Colin Smithpeter. DARPA NSF Thank you for your time