Abstract

An analysis of conventional optical arrangements for the measurement of dichroic ratios in the infrared region reveals that such measurements may be in error by factors up to 3 or more. These errors result from failing to account for the effects of prism polarization and of the imperfection of polarization in the transmitted beam of multiple plate AgCl polarizers. Elimination of the effect of prism polarization by a method proposed by Elliot, Ambrose, and Temple is shown to be relatively ineffectual when a transmission polarizer is employed. The magnitude of the error varies with the true dichroic ratio and with the optical density of the sample for polarized radiation parallel to one of the optic axes. A frequency dependent parameter is found to account for relatively isotropic intensity losses resulting from absorption and scattering by the AgCl in the polarizers; observed values of this parameter are given for three wavelengths, 1.67μ, 3.85μ, and 4.80μ.

© 1955 Optical Society of America

Ratio Measuring Twin-Beam Photometer*

Marcel J. E. Golay
J. Opt. Soc. Am. 45(6) 430-433 (1955)

Calibration and Use of a Cesium-Iodide Prism in the Infrared

I. M. Mills, J. R. Scherer, Bryce Crawford, and M. Youngquist
J. Opt. Soc. Am. 45(10) 785-787 (1955)

Some New Formulas for Determining the Optical Constants from Measurements on Reflected Light

R. W. Ditchburn
J. Opt. Soc. Am. 45(9) 743-748 (1955)

Representation of the Angular Distribution of Radiation Scattered by a Spherical Particle*

Chiao-Min Chu and Stuart W. Churchill
J. Opt. Soc. Am. 45(11) 958-962 (1955)

An Integrating Sphere for Measuring Diffuse Reflectance in the Near Infrared

John A. Jacquez, Wayne McKeehan, John Huss, James M. Dimitroff, and Hans F. Kuppenheim
J. Opt. Soc. Am. 45(10) 781-785 (1955)