Scale model experimentation: using terahertz pulses to study light scattering

Phys Med Biol. 2002 Nov 7;47(21):3823-30. doi: 10.1088/0031-9155/47/21/321.

Abstract

We describe a new class of experiments involving applications of terahertz radiation to problems in biomedical imaging and diagnosis. These involve scale model measurements, in which information can be gained about pulse propagation in scattering media. Because of the scale invariance of Maxwell's equations, these experiments can provide insight for researchers working on similar problems at shorter wavelengths. As a first demonstration, we measure the propagation constants for pulses in a dense collection of spherical scatterers, and compare with the predictions of the quasi-crystalline approximation. Even though the fractional volume in our measurements exceeds the limit of validity of this model, we find that it still predicts certain features of the propagation with reasonable accuracy.

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Validation Study

MeSH terms

  • Electromagnetic Phenomena / instrumentation
  • Electromagnetic Phenomena / methods
  • Fourier Analysis
  • Light*
  • Materials Testing / instrumentation
  • Materials Testing / methods*
  • Microspheres
  • Microwaves*
  • Models, Molecular
  • Optics and Photonics / instrumentation
  • Pilot Projects
  • Polytetrafluoroethylene / chemistry*
  • Refractometry / instrumentation
  • Refractometry / methods*
  • Scattering, Radiation
  • Sensitivity and Specificity
  • Spectrum Analysis / instrumentation
  • Spectrum Analysis / methods*

Substances

  • Polytetrafluoroethylene