Concentrating characteristics of the ellipsoidal concentrator–radiation source system in an optical medium

Abstract

The features of radiation concentration by an ellipsoidal concentrator are considered for the case in which the concentrator, the radiation source, and the receiver are in the optical medium. Investigations are conducted based on a photometric model that we developed that takes into account the features of the source radiation in the optical medium and change in the radiation indicatrix medium. It is found that, in contrast to direct radiation, in the case of radiation concentration in an optical medium, the irradiance will always increase, since, at the second ellipsoid focus, it increases in proportion to the square of the refractive index of the medium. It is shown that these effects do not depend on the refractive index of the material of the radiation source bulb. Thus, since the radiation source flux is constant both in air and in medium, increasing irradiance leads to a reduction of the source image spot in the medium.