Techniques of Single-shot Thermometry by Degenerate Four-wave Mixing.

Abstract

A summary of single shot techniques of thermometry by degenerate four wave mixing was presented in this paper. Thermometry by making population measurements via multishot laser scanning is impractical in many pulsed or short duration facilities. Conventional single shot DFWM techniques suffer from a variety of problems, including thermal grating interferences and complicated signal analysis. Au unconventional single shot FWM technique was discussed and analyzed using the linearized equations of hydrodynamics and light scattering. In this technique the signal beam scattered off laser induced (thermal) acoustic gratings is time resolved revealing information about the evolution of the gratings. The thermal diffusivity, acoustic damping coefficient, and sound speed (thereby temperature) are readily extracted from an analysis of the signals. The merits and limitations of both techniques were discussed.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1994
Accession Number
ADA302218

Entities

People

  • Eric Cummings

Organizations

  • California Institute of Technology

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Detection
  • Diffraction
  • Dye Lasers
  • Fluid Flow
  • Knudsen Number
  • Laser Beams
  • Laser Induced Fluorescence
  • Laser Pulses
  • Lasers
  • Liquid Dye Lasers
  • Nonlinear Optics
  • Optical Properties
  • Optics
  • Scattering
  • Spectra
  • Spectroscopy
  • Wave Mixing

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Optical Physics and Photonics.
  • Thermal Physics or Thermal Science.

Technology Areas

  • Directed Energy