US Patent 7884832 Calibrating RGBW displays

A method for calibrating a display device having four or more channels, including three main channels which include in their gamut a desired display white point, and one or more further channels, said display device also having one or more individual adjustment controls for each channel. The method uses a series of targets, which are each one or more activated display settings at which the luminance and chromaticity coordinates are measured and recorded.