Abstract

An exact expression for the emissivity of an ideally diffuse, gray, isothermal, spherical cavity is derived directly, making no geometrical approximations, and is shown to agree with the results of DeVos, Gouffé, and Sparrow and Jonsson, as compared by Fecteau. It appears that, even under ideal conditions, the spherical configuration is the only one that will have uniform isotropic emissivity over a wide angle, approaching a full hemisphere, across the entire aperture.

© 1968 Optical Society of America

The Emissivity of the Diffuse Spherical Cavity

M. L. Fecteau
Appl. Opt. 7(7) 1363-1364 (1968)

Effective Emissivity of a Spherical Cavity

P. Campanaro and T. Ricolfi
Appl. Opt. 5(6) 929-932 (1966)

Cavity radiators: an ecumenical theory

F. O. Bartell and W. L. Wolfe
Appl. Opt. 15(1) 84-88 (1976)

Calculation of the effective emissivity of a cavity having non-Lambertian isothermal surfaces

Y. Ohwada
J. Opt. Soc. Am. A 16(5) 1059-1065 (1999)

Radiometric Properties of Isothermal, Diffuse Wall Cavity Sources

Raymond J. Chandos and Robert E. Chandos
Appl. Opt. 13(9) 2142-2152 (1974)