beamcolors

Beamcolors refers to the perceived color of a light beam, particularly in atmospheric conditions where the light interacts with particles in the air. This phenomenon is most commonly observed with searchlights, spotlights, and lasers. The color of the beam is not inherent to the light source itself but is a result of how the light is scattered and absorbed by the medium it travels through.

In clear air, light beams tend to appear white or near-white, as all wavelengths are scattered relatively equally. However, when dust, smoke, fog, or water droplets are present, selective scattering and absorption become more pronounced. Shorter wavelengths, such as blue and violet, are scattered more readily than longer wavelengths, like red and orange. This effect is similar to why the sky appears blue during the day.

Therefore, a light beam passing through a hazy or smoky atmosphere might appear to have a colored tint. For instance, a white spotlight in a smoky club might exhibit a reddish or orangish hue because the blue light is scattered away more effectively, leaving the longer wavelengths to reach the observer. Similarly, lasers, which are monochromatic (emitting a single wavelength), will appear as that specific color if the beam is visible. The visibility of a laser beam is also dependent on the presence of aerosols in the air to scatter the light towards the viewer. This principle of light scattering is fundamental to understanding why beamcolors vary.