LED Emergency Vehicle Lighting

When police lights were first invented, they were large devices with stationary sealed beam incandescent bulbs. These eventually evolved into rotating beacons in the 50's and into full size lightbars in the late 60's and early 70's, all with sealed beam par36 light bulbs. As the police lights evolved, the lighting technology stayed pretty much the same. In the 80's, police lights were starting to use open reflectors with halogen bulbs. This was a major step forward as it allowed the configuration of the police lights to become much more flexible but they still required a lot of amperage to operate. Early in the 90's, strobe light technology offered another viable solution. Finally, in the late 90's and into the '00's, LED technology improved significantly to the point where LED's became a viable alternative for police light applications.

LED's are nearly the panacea of police lights. They have very, very low power requirements, they are now very bright, especially when used in multiples and the color is very true. The downside is that LED's, because they are still relatively new in the marketplace, they are still much more expensive than either halogen or strobe technology. And just as poignant is the split between those that love LED's and those that don't. LED's still have yet to evolve into a mature product. While they are bright, they have several technical drawbacks. 

While LED's generate heat, it's much less than that generated by halogen or strobe lighting. The problem is, LED's degrade as the temperature rises, both from it's own generated heat as well as the ambient temperature. This causes the light output to degrade as well. In a very hot environment, the problem is exacerbated. Over time, a blue LED can appear to emit a bluish green hue. Red and amber LED's are not as prone to color shift as blue. So manufacturers are working on ways to keep the LED's cool without having to add fans and other cost increasing solutions. Another issue is the fact that LED's generate significantly less heat than halogen or strobes and when the LED's are in an external light head or light bar, this can be problematic for emergency responders in the winter. The LED's are not able to melt ice and snow, thus rendering the LED emergency lighting useless. Thus the issue of heat is a double edged sword.

As LED technology matures, the problems will be overcome and the end result will be the development of highly effective emergency vehicle police lights which will light the way for many years to come.