2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/66949It is shown that the problem of designing a two-reflector system transforming a plane wave front with given intensity into an output plane front with prescribed output intensity can be formulated and solved as the Monge-Kantorovich mass transfer problem.25 pages, 2 figuresAnalysis of PDEsOptimization and Control35J65; 78A05; 49K20Optical design of two-reflector systems, the Monge-Kantorovich mass transfer problem and Fermat's principletext