The dynamic range of many real-world environments greatly exceeds the dynamic range of display systems based on liquid-crystal (LC) panels. Using a matrix of locally-addressable high-power LEDs, both the black level and the brightness can be improved. In this contribution, we describe a method for boosting luminance without installing additional light. The method is applicable to colour-sequential displays. We also validate the performance of the solution in terms of average luminance gain on a large set of video data. The results show an average luminance increase of 143% for 240 backlight segments.