Abstract: Laser displays, known for their advantages of wide color gamut, high resolution, and high brightness, have emerged as representatives of the fourth generation of wide color gamut displays. To achieve even larger color gamut in display technology, combining multi-primary color techniques with laser displays has been explored. However, a challenge arises due to the variation of color temperature in the white balance point of display systems, which can affect the range of colors that these systems can reproduce. To address this issue, theoretical research was firstly conducted to investigate how different color temperatures impact the three-dimensional color gamut, volume-coverage ratio, and light efficiency of a four-primary laser display system, and then these theoretical findings were experimentally validated. The study reveals that, in multi-primary laser display systems, using higher color temperatures for white balance points can expand the three-dimensional color gamut and enhance color representation. And at the same time, as the color temperature increases, the light efficiency value will rise, albeit with a slight decrease in color gamut volume-coverage ratio. For those prioritizing superior color fidelity, a color temperature of 6500 K is recommended. While taking into account factors such as the volume of threedimensional color gamut, color gamut volume-coverage ratio and light efficiency, it is advisable to choose an appropriate color temperature within the range of 6500 K to 20000 K. This research provides valuable insights for the design and construction of four-primary and multi-primary color display systems.

Key words: laser techniques, four-primary displays, color gamut volume, gamut coverage, light efficiency, color reproduction