Since You Asked: Blue light special
What's the deal on these bright blue lights we are seeing more of? They are very hard on our eyes and I wouldn't buy a car with them on it. The person driving with them probably likes them but with my regular lights on high I can see very well. Are they here to stay or just a fad?
— Jim L., via e-mail
Those bluish lights you've seen in auto headlights are xenon high-intensity discharge lamps, an improvement from the more common halogen headlamps most cars currently use. Halogen lamps were preceded by "old-fashioned" incandescent tungsten filament type bulbs, which are rapidly going out of favor everywhere.
For the same reason Edison's old bulbs are dying out in favor of compact fluorescents in homes, you're likely to see more of these xenon HID headlamps because they use less energy but produce more light. They aren't too popular right now because of their cost. Searching online, we found a single replacement bulb can cost anywhere from $30 to more than $100. The cost is likely to come down if they hit the mainstream and mass production.
Most people like them precisely for the reason you don't like them, Jim. They are bright and cast a light similar to daylight spectrum. After-market HID lamp sets are available and popular with young adults who like to trick out their Hondas and Acuras, and it's likely those are the worst offenders because the lamps reflectors are easily misaligned, but even factory installed headlamps can be blinding. Let's hope the headlamp designs will improve to prevent stray light from hitting the eyes of oncoming drivers. We're with you — those things can be worse than an oncoming driver having high beams or fog lamps on. Oh, and for the record, fog lamps are illegal to use without fog, and they must be dimmed for oncoming cars.