The rainbow effect is an artifact in the display of video signals with DLP projectors (DigitalLight
Processing), in particular with DLP projectors in 1-chip design. In moving scenes, the filter colors of the RGB color wheel appear as a rainbow at the edges with strong contrast changes.
The rainbow effect is caused by the RGB color wheel and its rotational speed. With higher rotational speed, this annoying rainbow effect decreases, although it depends on the personal perception of the viewer. Experience shows that at an RGB rotation frequency of the color wheel of 50 Hz to 150 Hz, the effect is visible to all viewers and is perceived as disturbing. At 200 Hz to 250 Hz, the rainbow effect is significantly less and only visible with high contrast. At over 300 Hz RGB color wheel frequency, it is only perceived by some viewers.