MINIMAX REFINING OF WIDE-BAND ANTIREFLECTION COATINGS FOR WIDE ANGULAR INCIDENCE

The design of antireflection coatings at any light incidence is a chal lenging task in optics. To this aim, a minimax method is presented: it minimizes the maximum deviation of the spectral reflectance from the desired specifications over the wavelength for a given set of incidenc e angles. Refining is limited to lossless coatings with assigned refra ctive indices and undetermined thicknesses; the algorithm consists of iterating appropriate linear optimization steps. In the examples some minimax-refined coatings are compared with coatings reported in the li terature.