Wedge-shaped light concentrator using total internal reflection

One- and two-stage concentrations using wedge-shaped concentrators were pro posed as static solar concentrators, where the light changes its direction with specuIar reflection at the rear surface and refraction or total intern al reflection at the front surface. The condition for the total internal re flection gives the critical tilt angle of the wedge and consequently determ ines the maximum value of the concentration ratio. When the tilt angle is l arger than the critical one, only the reflection at the front surface lower s the collection efficiency. Two-stage concentration can give a higher conc entration ratio than one-stage concentration. A truncated-cone-shaped conce ntrator with tracking system can give higher concentration ratios than the two-dimensional wedge-shaped concentrators. (C) 1999 Elsevier Science B.V. All rights reserved.