Freeform design of a two-reflector system to collimate and shape a point source distributionA.H. van Roosmalen, M.J.H. Anthonissen, W.L. IJzerman and J.H.M. ten Thije BoonkkampEPJ Web Conf., 255 (2021) 02002DOI: https://doi.org/10.1051/epjconf/202125502002