Underwater Optical Imaging: Systems and Insights Related to Volume Scatter in the Ocean

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Underwater Optical Imaging Systems and Insights
Related to Volume Scatter in the Ocean

• Jules S. Jaffe
• Marine Physical Laboratory
• Scripps Institution of Oceanography, La Jolla, CA
  

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Jaffe Lab Sensing of Underwater Marine Life
Fish
phytoplankton
Zooplankton
microbes
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Introduction to Underwater Optical Imaging
The Experts!
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Notes on the history of underwater
imagingAlexander the Great
From ONR report, 400 BC
Heres what they really did
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First Underwater Picture TakenWilhelm Bauer
1856
Der brandtaucher (sea devil picture unavailable)
Sea Devil, built St. Petersberg in 1855 53 x
11.5 first underwater picture, 1856 foggy
rocks Also underwater musicband aboard
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Narcis Monturial inventor of the Catalan
submarine Barcelona, 1861
Ictineo
Plus intra, plus extra (Far down! Far out!)
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Some Notes on the History of Underwater Diver
Taken Photographs
1893 Louis Boutan early pictures
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Conventional Imaging Systems

• camera

Common backscatter
Blurred image component
lights
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Image Considered As a Superposititon of Component

• Direct Blurred
  Backscattered

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Improving Image Visibility

• Schemes to combat backscatter
• Increased Camera - Light Separation
• Lidar based systems.
• Laser line scan systems.
• Schemes to combat forward scatter
• Line acquisition systems (STIL).
• Laser line scan systems (LLSS, 3DSEASCAN).
• Coherence and Polarization
• Special cases relying on properties of the wave
  field.

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Laser Scanning Systems

• Bill Stachnik LOOKC system 1970s
• Declassified in the 1990s
• Bryan Coles LLSS (Laser Line Scanner System)
• Raytheon
• Northrup Gruman
• Panama City Group (NAVY Lab)
• Moore and Jaffe (3D Sea Scan)
• Aculight - SIO (Laser Line Scanner System -
• small/efficient)

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Laser Line Scan System
Basic Concept of the LLSS (courtesy M. Strand)
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Survey of the USS Monitor
Schematic of Hull Image Mosaic
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Laser Line Scan System

• A Special Arrangement for Color Imaging

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Activities of Jaffe Group in Underwater Optical
Imaging- Modeling Theory

• Uncles Model (developed at Woods Hole
  Oceanographic Institution)
• Originally at SIO - transitioned to WHOI gt SIO
  (1970s - present)
• Monte Carlo Model (to prove linearity of Point
  Spread Function)
• PSF(2d) PSF(d) ?PSF(d)
• Joint Estimation of Underwater Images and Imaging
  Parameters
• Ocean Optics Meeting (2002)

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• Laser Line Scan System Modeling

Jaffe, J. S., Optics Express, 13 (3) 738-748,
2005
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Activities of Jaffe Group in Underwater Optical
ImagingImaging System Development

• 3DSEAS
• FIDO-?-p
• Diffraction Tomography of Marine Bacteria

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My First Shipwreck
Argo vehicle 1985
Boiler at 3800 m
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Radiance The Final Frontier
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3D Sea Scan
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3D Sea Scan
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Second generation Laser Bathymetry system
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3D Scan of Manta Mine (in air)
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Example of 3D data

• Turtle grass on white sand Lee Stocking Island,
  COBOP

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Sea Surface Scan
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Imaging Systems for Biology

• Free Fall Imaging System for Observing
  Phytoplankton FIDO-?

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FIDO - ? Imaging Geometry
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FIDO - ?
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Cruise Results 2001
Strong Spatial Gradients
Diatom Chains
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Elastically Scattered light and Particle Image
Velocimetry (PIV)
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Pelagic 3D PIV System
Laser
Camera II Double shot mode (100ns) 4 color filter
wheel 10 Hz
Camera I Double shot mode (100ns) 4 color filter
wheel 10 Hz
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3D Particle Imaging Velocimetry
System configuration
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Characterizing Volume Scatter in the Ocean
Empirical Oceanographic Components
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Empirical Characterizing of Volume Scatter

• Inherent Optical Properties (independent of the
  light field)
• Absorption
• Scatter
• Volume Scattering Function (phase function)

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Inherent Optical Properties
Absorption and scattering coefficients
Volume scatter functions
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Dynamical Observation of Ocean Scatter (2006)
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Oceanographic Characterization
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Characterizing the Upper Ocean (Jaffe/Franks)
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Components of the Ocean

• Marine Life Scatter regime
• Large animals (100,000 ?) geometric
• Small animals (2000 ?) geometric
• Bacteria (2 ?) Mie
• Viruses (.1 ?) Rayleigh
• Dissolve Organic Matter (DOM)(.01 ?) Rayleigh
• Inorganic Components
• Bubbles (10 ? - 1 mm)
• Terragenous runoff (minerals) ( lt 2 ?)

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Underwater Imaging - Future

• Increased knowledge of the environment
• Spatial and Temporal correlations and variance
• Particulate matter (distribution, size)
• Absorptive and fluorescent particles
• Vertical variance and horizontal stratification

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Underwater Imaging - Future

• Advances in Hardware

Illumination systems Sensing systems

• Advances in Software
• Image processing and understanding

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