A comparison of different correlations commonly used to describe the limb darkening effect is made. A somewhat new correlation is proposed which predicts the values to within ±1.5% of the experimental values. Using a conventional ray trace technique and assigning proper weight factors to each ray, the distribution of the local concentration ratio over a flat absorber placed in the focal plane of a cylindrical parabolic trough is also determined.
© 1985 Optical Society of America
B. S. Negi, N. C. Bhowmik, S. S. Mathur, and T. C. Kandpal, "Solar limb darkening and ray trace evaluation of solar concentrators," Appl. Opt. 24, 296-298 (1985)