RGB Wave Interference

Sunlight contains every wavelength — a continuous spectrum. But our eyes only have three types of color receptor (red, green, blue), so we can model color perception with just three waves. When all three are present equally, we see white.

Two waves can add or cancel

Drag either wave left and right

Wavelength determines color

White light is made of colors

What happens when two white lights interfere?

Drag either composite wave left and right

Where do the two whites come from? A thin film.

Note: real thin films are only a few hundred nanometers thick — about the same size as a single wavelength of visible light. If we drew both to scale, either the film would vanish or the waves would show just one cycle. So the film is drawn exaggerated (~4×) for visibility. The interference color is still computed from our synthetic wave, so what you see is what would show up for this composition of light.
Drag to change the angle of incoming light
Eye icons created by Uniconlabs - Flaticon