Avoiding on‐screen metamerism in N ‐primary displays

— The present paper describes a method for using more than three primaries in an additive‐primary display. The method ensures that each tristimulus specification can be produced in no more than one way, even if a non‐singular filter ( i.e. , one that does not reduce the dimensionality of color‐matching space) is interposed between the screen and the viewer. Starting with N primaries, the method uses only three at a time, but these may be composites — fixed linear combinations of the original N . As further insurance against on‐screen metamerism, a criterion on the primary spectra, based on the Binet‐Cauchy theorem, ensures that a triad of primaries keeps its right/left‐handed chromaticity ordering when a filter is interposed.