Spectroscopic temperature measurement
AssigneeAllied Chemical Corporation
InventorJoseph J. Barrett
Life of this patent
Estimating the term…
Abstract
A method and apparatus for determining the temperature of gaseous materials are provided. Light produced by scattering in a gaseous material and having spectral components periodic in frequency is collected, collimated and transmitted by a light conditioning means to an interferometric means. The interferometric means selectively separates periodic spectra from the light and transmits the spectra in the form of a detectable signal containing first and second branches of the spectra. Means are provided for measuring the intensities of the branches and detecting and recovering the intensity ratio thereof, which is correlated with the temperature of the gaseous material.
Claims17
Apparatus for determining the temperature of a gaseous material by analyzing light having spectral components periodic in frequency, comprising:
- a. light conditioning means for collecting, collimating and transmitting said light;
- b. interferometric means adapted to receive said light for selectively separating periodic spectra therefrom and transmitting said spectra in the form of a detectable signal, said interferometric means having interference-producing means for providing a plurality of transmission windows regularly spaced in frequency, the frequency spacing between adjacent windows being adjusted to depart from an odd integral submultiple, n, of the frequency difference between adjacent spectral components of the periodic spectrum of said gaseous material, said odd integral submultiple being at least three so as to produce a split-fringe containing first and second branches of the components, and scanning means for causing the transmission peaks for adjacent nth orders to substantially coincide with the spectral lines of either branch of the components, whereby each branch of said split-fringe is derived from a plurality of periodic spectral lines and has an integrated intensity substantially equal to their sum;
- c. signal conditioning means for measuring the intensity of each of said branches;
- and
- d. detecting means for indicating and recording the intensity ratio of the branches, said intensity ratio correlating with the temperature of said gaseous material.
A method of determining the temperature of a gaseous material by analyzing light having spectral components periodic in frequency, comprising the steps of:
- a. collecting, collimating and transmitting said light in the form of a ray path;
- b. interferometrically separating periodic spectra from said light by directing said light through a plurality of transmission windows regularly spaced in frequency, the frequency spacing between adjacent windows being adjusted to depart from an odd integral submultiple, n, of the frequency difference between adjacent spectrum of said gaseous material said odd integral submultiple being at least three so as to produce a split-fringe containing first and second branches of the components, and scanning said ray path to cause the transmission peaks for adjacent nth orders to substantially coincide with the spectral lines of either branch of the components;
- c. transmitting a detectable signal composed of said split-fringe, each branch of said split-fringe being derived from a plurality of periodic spectral lines and having an integrated intensity substantially equal to their sum;
- d. measuring the intensity of each of said branches;
- and
- e. detecting and recording the intensity ratio of the branches, said intensity ratio correlating with the temperature of said gaseous material.
Dependencies are inferred from the claim text.