To provide a contrast improvement for projection screens used with the laser display technology, a thin selective reflecting filter was designed. To overcome the problem of unknown starting designs and permit a new evaluation technique, an evolutionary algorithm was implemented. Due to the lack of known target spectra rather than known features of the target spectra, a novel evaluation procedure using color metrics was implemented. Different selective reflecting filters were deposited on glass as well as on plastic substrates by reactive mid-frequency magnetron sputtering. In-situ ellipsometry was used for process control and in-situ re-design of the filter. (C) 2003 Elsevier B.V. All rights reserved.