Design and simulated performance of a CARS spectrometer for dynamic temperature measurements using electronic heterodyning
Abstract
A new design for generating CARS signals and for the detection and processing of these signals is presented and evaluated. The design is based on electronic heterodyning of the CARS spectrum of nitrogen at two selected narrowband frequencies, ratioing the resulting signal strengths, and comparing this ratio with a theoretically derived temperature scale. A reference cell is incorporated into the design for system calibration and for accurate temperature measurements. The spectrometer is found capable of measuring temperature in the submillisecond time scale with an accuracy of 10 percent in the 1000-2000 K temperature range. A typical result using the Hg(x)Cd(1-x)Te photomixer for T = 1500 K, Delta T = 50 K is a SNR of 21 dB and a data collection rate of 300 Hz.
- Publication:
-
Applied Optics
- Pub Date:
- April 1989
- DOI:
- 10.1364/AO.28.001409
- Bibcode:
- 1989ApOpt..28.1409D
- Keywords:
-
- Nonlinear Optics;
- Optical Heterodyning;
- Raman Spectroscopy;
- Temperature Measurement;
- Vibrational Spectra;
- Energy Levels;
- Lithium Niobates;
- Mercury Cadmium Tellurides;
- Photometers;
- Signal To Noise Ratios;
- Instrumentation and Photography;
- COHERENT ANTI-STOKES RAMAN SCATTERING;
- TEMPERATURE;
- HETERODYNING;
- SPECTROSCOPY: RAMAN;
- SPECTROSCOPY: LASER