I remember cars used to have only one (1) amber fog light on the front. Instead of shining it straight ahead, they placed it so it would shine down at an angle so the glare wouldn't be as bad. Here is an article that I agree with on the subject;
http://www.ehow.com/how-does_4885332_fog-lights-work.htmlHow Do Fog Lights Work?
By Steve Smith, eHow Contributor
Visiblity in Fog
1. Fog lights are designed to reduce glare that occurs while you are driving through thick fog. When you flip on your headlights in a patch of fog, most of the light is reflected back at you from the water droplets in the cloud of fog. Water is reflective of light almost to the point of being a mirror, so whenever you turn on your headlights in a fog, you are going to receive most of the light thrown out back in your eyes. This creates a blinding patch of light in front of you.
Angling for Better Vision
2. The idea behind fog lights is to reduce the amount of glare thrown back at you. The fog lights are angled downward toward the road at an angle, so when you turn them on, the light is thrown across the road in front of you and not straight ahead of you, where it can be reflected back. The light is not reflected back into their eyes. This gives you some visibility of the roadway, without blinding you. The color of the lights has no bearing on their use in fog. Today, yellow or any other color is not recognized as being "better" at penetrating fog. It may have more use as a safety mechanism for oncoming traffic.
Benefits and Drawbacks
3. Fog lights will give you a little more visibility and reduce glare while driving down a foggy road. You will be able to see the roadway more clearly and suffer through less glare. However, some people say that these lights really don't give you an advantage. The fog lights only light up a small section of road, because they are angled and mounted lower on the vehicle. They do not give other drivers enough warning and sometimes can blind other motorists as they approach you. They also do not cut through the fog in any way. The lights themselves are the same bulbs are headlamps, LEDs or HIDs. Any yellow lights use a color filter to produce the yellow color that may reduce some of the blinding glare, which makes them appear to cut through the fog.
