Fog lights are basically the lights that are mounted on the front fascia of the car or truck that are used for improved visibility during misty or foggy conditions. The fog lights appear in numerous colors as well as intensities, but almost all the vehicles come with fog lights which are important to navigate the poor weather.
As compared to the traditional fog lights, they used to come in yellow color as they are clearly visible. However, many claimed that they should come in single color light and not white so that the dispersion is minimized when the light hits the water vapor and spreads in various directions. Also claimed that the red light might be more ideal color, but it is already used as stop lights and brake lights and if used as fog light then drivers could get confused. Next to red, was the suggestion for yellow light as it has long wavelength of visible lights.
However, scientifically it was found that the light has to go hand in hand with the water molecules in fog for proper dispersion. Though the initial car companies were not aware of the fog lights impact with the size of water vapor molecules, they chose yellow lights that minimize the blurriness casts by fog lights. In any case, a yellow light later didn’t seem suitable as yellow lights or yellow signals indicate that the driver has to slow down and check for obstacles on the way.
Even numerous fog lights and halogen lights have been used by various manufacturers that enable them to glow at far hotter temperatures as compared to what the traditional lights do. Halogen lights have been proved to be a benefit as it includes tighter beam as compared to the incandescent lights. Some of the newer cars can be found with halogen lights and use various minerals to function such as sodium, halide and mercury. Such lights get a little purplish hue rather than more traditional yellow colored lights.