Optical Imaging of Objects in Turbid Medium With Ultrashort Pulses

Abstract

Photons are seriously scattered when entering turbid medium; thus the images of objects hidden in turbid medium can not be obtained by just collecting the transmitted photons. Early-arriving photons, which are also called ballistic or snake photons, are much less scattered when passing through turbid medium, and contains more image information than the late-arriving ones. Therefore, objects embedded in turbid medium can be imaged by gathering the ballistic and snake photons. In the present research, we try to recover images of objects in turbid medium by simultaneously "time-gate" and "polarization- gate" to obtain the snake photons. An Argon-pumped Ti-Sapphire laser with 1OOfs pulses was employed as light source. A streak camera with 2ps temporal resolution was used to extract the ballistic and snake photons. Two pieces of lean swine meat, measured 4mmX3mm and 5mmX4mm, respectively, were placed in a iOcmXlOcmX3cm acrylic tank, which was lull of diluted milk. A pair of a polarizer and an analyzer was used to extract the light that keeps polarization unchanged. The combination of time gating and polarization gating resulted in good images of objects hidden in turbid medium.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2000
Accession Number
ADP011213

Entities

People

  • Chen Yang
  • Chia-wei Sun
  • Chih-yu Wang
  • Chii-wann Lin
  • Yean-woei Kiang

Tags

Communities of Interest

  • Biomedical

DTIC Thesaurus Topics

  • Analyzers
  • Biomedical Engineering
  • Cameras
  • Cross Polarization
  • Data Acquisition
  • Detectors
  • Engineering
  • High Resolution
  • Imaging Techniques
  • Ionizing Radiation
  • Light Sources
  • Measurement
  • Optical Properties
  • Polarization
  • Polarizers
  • Scattering
  • Streak Cameras

Fields of Study

  • Physics

Readers

  • Image Processing and Computer Vision.
  • Optical Physics and Photonics.

Technology Areas

  • Directed Energy