Abstract

The spectral slit width of a monochromator is defined as the half-intensity band width of frequencies passed by the exit slit. This paper discusses its measurement using methods similar to those used to measure the frequency transmission of electrical networks. A Fabry-Pérot interferometer, used as a sinusoidal signal generator, produces interference fringes constantly spaced in wave numbers at a known amplitude input to the monochromator. It can be shown that the attenuation of the fringe pattern as the spacing is changed is a function of the exit-slit output-intensity distribution function. From this information the spectral slit width in any spectral region can be measured and the exit-slit function indicated.

The sensitivity of measurement is limited by the fringe amplitude obtainable from the interferometer, which is a function of the reflectivity of the interferometer plates and their adjustment. Rays passing through the interferometer at other than normal incidence tend also to damp the fringe pattern.

© 1955 Optical Society of America

A Simulated Channel Spectrum*

D. H. Rank and Jean M. Bennett
J. Opt. Soc. Am. 45(1) 46-50 (1955)

Photoelectric Raman Spectrometer

John U. White, Nelson L. Alpert, and Arthur G. DeBell
J. Opt. Soc. Am. 45(3) 154-166 (1955)

Quantitative Method for Measuring the Resolution of a Large Grating*

D. H. Rank, J. N. Shearer, and Jean M. Bennett
J. Opt. Soc. Am. 45(9) 762-766 (1955)

Interferometric Frequency Calibration of Infrared Spectrometers

Svend Brodersen
J. Opt. Soc. Am. 46(4) 255-258 (1956)

Interferometric Measurement of Wave-Front Aberrations in Gratings and Echelles*

George W. Stroke
J. Opt. Soc. Am. 45(1) 30-35 (1955)