Patent ID: 8711085

Claim:
A display comprising: a spatial light modulator comprising an array of controllable pixels, each pixel comprising a plurality of sub-pixels; a plurality of primary color light-emitting elements arranged to illuminate the spatial light modulator with light of a plurality of colors; at least one broadband light-emitting element having a spectral bandwidth at half maximum of at least 150 nm and being arranged to illuminate the spatial light modulator; and a controller that is configured for: estimating a light field at the spatial light modulator, wherein the light field is generated by one or more of the light-emitting elements, determining a driving signal for each sub-pixel based on a value of the estimated light field at a location of the sub-pixel, and applying the driving signals to the sub-pixels; wherein: the broadband light-emitting element is controllable to alter an amount of the light at a location on the spatial light modulator and the controller is connected to receive image data and configured to determine from the image data a chromaticity corresponding to the location on the spatial light modulator and, based at least in part on the chromaticity, control the amount of the broadband light at the location on the spatial light modulator; the controller is configured to determine, from the chromaticity determined from the image data corresponding to a location on the spatial light modulator, a saturation index for each of a plurality of primary colors, wherein the saturation index for each primary color is a measure of how closely light of the primary color alone matches the chromaticity, and, based on the saturation indices, control the amount of the broadband light at the location on the viewing screen; and the controller is configured to determine whether the chromaticity falls within a region of chromaticity values, wherein the region corresponds to, or is a region within, a gamut that can be accurately reproduced if the spatial light modulator is illuminated only by light from the at least one broadband light-emitting element, and, if so, suppress illumination of the location with the primary color light.