Laser Phosphor vs RGB laser: How does it work?

The light source in an RGB projector, also called direct laser projectors, contains individual red, green and blue lasers. As we’ve all learned in kindergarten, these primary colors are the building blocks of all other colors. By combining different proportions of these three lasers, the projector can reproduce millions of different shades and hues. The laser output is mixed, processed by the projector’s DMD (Digital Micromirror Device) chips and directed through the lens on the projection canvas.

However, instead of using three different colors, the laser phosphor projectors use just one. The majority go for only blue laser diodes. “Why blue?”, you might ask. Well, the choice for blue lasers is based on the high density and power efficiency of this color. The blue light from the laser shines onto a spinning yellow phosphor wheel. The chemical compound phosphor absorbs the blue light, and radiates a bright, yellow light. This broadband yellow light is captured and split into the primaries using a color wheel. These can then be used to produce the colored images on the canvas.