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Automotive lighting has become a hot button since the arrival of new lighting systems that produce a bright, bluish light. With winter comes the need to spend more time driving in the dark with our headlights on, and renewed interest in and complaints about these new lighting systems.

A properly engineered and installed automobile lighting system does not create problems, it alleviates them.

The problem with these new "blue" lights is that the majority are aftermarket systems, and are simply very bright and powerful bulbs installed in a lighting system not designed for them. And, in some cases, factory systems that are poorly aligned.

The disparity in height between a tall pickup or SUV and a smaller or lower vehicle also can result in even properly aimed lights projecting into the eyes or mirror of a lower vehicle.

Let's look at two issues here: glare and the type of light.

Glare can be defined as a condition of discomfort in the eye and reduction in visibility that results when a bright light enters the field of vision, especially when the eye is adapted to the dark.

The lighting industry breaks glare into two categories: discomfort and disability. Discomfort glare causes an annoying or painful sensation and fatigue. Disability glare reduces the ability to distinguish small changes in brightness and can reduce the distance at which we can identify low-contrast objects.

There are many sources of glare as it relates to driving -- bright sun during the day and a host of issues at night: unshielded street lights, bright advertising signs, weather conditions, improper use of high beams, poorly aimed headlights, improper positioning of lights (too high) and illegal lights (high-wattage bulbs in non-compliant, aftermarket installations).

Research, such as that conducted by the University of Michigan's Transportation Research Institute, finds that most drivers "overdrive" the headlights on many of today's vehicles.

"The critical safety need in low-beam lighting is seeing distance," UMTSI says. "Everyday experience as well as our formal analyses of crash data reveal that today's drivers routinely 'overdrive' their headlight beam pattern at night. The maximum safe speed with today's average low beams is only about 45 mph."

The search for improved lighting systems has led to the development and implementation of xenon headlights, also known as High Intensity Discharge or HID. Instead of a glowing filament as the source of light, these use a gas discharge process to create an arc. This results in a brighter light of a different colour.

If used in a system designed to control that additional light, such as at the side of the road on low beam, the enhanced vision is a significant safety factor. Xenon lighting provides approximately 45 per cent more light, while producing 25 per cent less glare.

Although expensive initially, xenon lights last far longer than conventional tungsten or halogen bulbs. More than 125 vehicle models equipped with xenon headlights are available in North America for the 2006 model year.

Another emerging technology being credited with enhancing safety, especially when combined with the increased and controlled illumination provided by xenon lighting, is AFS or Adaptive Front Lighting Systems.

These units improve illumination in various driving conditions by automatically modifying the beam pattern of the headlights according to speed, weather and road conditions. The headlamps move as the steering wheel is turned to the right or left to help illuminate the road earlier and allow drivers more time to see and react.

Because of their bluish-white colour, xenon or HID lights have become the focal point for complaints and concern. However, properly installed and aimed, xenon lights meet all safety codes and standards.

Headlight glare can be reduced by proper headlight aim, regular inspection and adjustment and control of non-compliant lighting systems.

globeauto@globeandmail.ca