Have you caught the rainbow effect while using a projector? The Rainbow effect, also known as RBE, is a visual phenomenon that occurs on projectors, it is the flashes of color perceived by viewers around the picture. Actually it is not something that happens to all sorts of projectors. The rainbow effect is a stroboscopic effect generated by the spinning color wheel on DLP projectors.

When you see flashes of blue, red and green when some watching fast-moving scenes or a very bright area on the image comes across the dark areas, this is exactly the rainbow effect we are discussing here.

To know more about the rainbow effect, we may have to learn about how DLP projectors work. DLP projectors have only one single chip so how do they generate different colors? It splits the light into red, green and blue by passing the light through a spinning color wheel, then use these colors to produce the primary colors. Therefore, the image on the screen is either red, or green, or blue at each instant in time, then our eyes will combine the three separate colors automatically. But the human eyes detect the red, green, and blue images at slightly different positions on the retina, and the splits of colors observed by viewers look like a rainbow. Hence rainbow effect is produced.

Why 3PLD projector won’t produce the rainbow effect? The high end home theater and commercial theater projectors are usually 3DLP projectors, containing three separate chips in charge of the color of red, green, and blue, which are combined into various colors before going out to the screen. Hence no rainbow effect exists in 3DLP projectors.