The optical engineer can apply unit sphere methods, used to find geometrical configuration factors in radiant heat transfer calculations, to calculate similar factors for irradiance and illuminance distributions in many optical systems. This paper illustrates how using a dummy reference sphere of arbitrary radius, and direct ray trace analysis, can greatly simplify photoradiometric calculations while achieving accuracies of better than 1%. Uniform and non- uniform light sources are treated. Examples are presented using different optical configurations and light sources including projection systems, scanners, illuminators, and several imagers.

Date Published: 15 April 1993
PDF: 15 pages
Proc. SPIE 1780, Lens and Optical Systems Design, 17800F (15 April 1993);

Published in SPIE Proceedings Vol. 1780:
Lens and Optical Systems Design
Hannfried Zuegge, Editor(s)