Seeing blue over high intensity headlights
Dear Answer Man, enlighten me, please, about car headlights that give off lavender light. Is this some new LED headlight? I find it difficult enough to see after glancing at halogen headlights, and adding the lavender ones I saw tonight in southeast Rochester was even more distracting. Are they even legal? — Denise
Truly colored headlights are illegal, but some of the new high-intensity lamps take on a shade of blue — maybe even lavender — in certain conditions and yes, they're distracting. Without getting into details, there are some factory-installed high intensity discharge (HID) headlights that are brighter, are said to cut through fog and bad weather conditions better than traditional lights, and have a bluer tint than halogen.
HID lights generate a plasma discharge arc between two tungsten electrodes, similar to some stadium lighting. Some of the bluer-tinted headlights you see on the road aren't true HID lights, though, and aren't much of an improvement for drivers.
I talked to a State Patrol trooper Friday who said the bluish headlamps are legal as long as they're not "predominantly" blue, purple or whatever. "They can cast a blue hue," he said, which is sufficiently vague for my purposes here.