Large Dynamic Range Real-time White Balance Control in Laser Display

Abstract

The colorimetric principle of white balance control in laser display is explored. According to the CIE1931 standard chromaticity system and Glassman's color mixing law, the brightness ratio of the three primary color laser light sources R(637nm), G(525nm), and B(450nm) matching the white point of the color temperature range from 6500k to 9300k is calculated. A set of three-primary color white balance control system was designed, which is integrated into the 100-inch laser TV developed by the research group. The characteristics of automatic white balance under the change of light intensity with a large dynamic range and changes in ambient temperature were studied. The experimental results show that when the output light intensity is attenuated by 40%, the color temperature can be accurately controlled in 6500K±50K; when the ambient temperature changes from 18°C to 28°C, the color temperature error can be controlled within 120K.