Now I understand
how deer feel when mesmerized by the lights of oncoming cars. The
strange blue glare of xenon, or High Intensity Discharge (HID)
headlights seems to draw the old eyeballs across the yellow line,
away from where they are supposed to be pointed. First used as far
back as 1991, it was only this year when the xenon lights really
caught my eye. Is it their brightness, or their novelty that steals
the attention?
According to
Transport Canada’s Marcin Gorzkowski, drivers reported a similar
phenomenon during the last major shift in headlamp technology.
Vacuum headlamps ruled the road for decades, until being replaced
through the 1980s by brighter halogen style lamps, causing some
drivers to see blue. The halogen gas, boosting the light emitting
from a tungsten filament, helped produce a beam that to opposing
drivers appeared bluish, and made the old style lamps look yellow in
comparison. Sound familiar?
Mr. Gorzkowski
says he participated in a test using all three generations of lamps,
and reports that each time the newer bulb was turned on, it appeared
blue, until all three shone side by side – and didn’t seem that
different from one another. He says that the blue business is more a
trick of the eye, because the newer bulbs are in fact so much whiter
that the old. HID lights have no filament inside, instead using an
electric arc that does not provide full spectrum of colour. The
light beam may also not be perfectly uniform.
Gorzkowski
believes that the eyes of opposing deer, I mean drivers, are being
drawn by the novel appearance of the HID lamps. As for me, perhaps I
have trained myself – but no longer am I involuntarily distracted.
The Transport Canada expert says there is a critical balance in the
design of headlights, between road illumination and glare
experienced other motorists. He says the new style lights are no
more blinding than the old – provided they are clean and aimed
properly. Of course, ice and dirt on the lens will disperse light to
where it should not be.
New lamps should
allow only some light to shine upwards, enough to illuminate
overhead signs. Roadside markers must also be seen, but the safety
tradeoff between user and everyone else gets tricky over on the left
side of the vehicle. The federal government regulates
manufacturer-installed headlights, and while lights may be aimed at
the factory, it is the dealer who should verify them before sale.
After that, its up to us to keep our beams pointed at the road.
Since the vast majority of vehicles don’t have “smart headlights”
that adapt to road conditions, it is simple consideration to be
aware of our aim. Gorzkowski says, “Again, this is explained in most
of the owners manual,” adding wryly, “that nobody reads.” Junk in
the trunk may also pitch the front beams higher.
Then there are
aftermarket bulbs – which the feds do not regulate. Some
off-the-shelf lamp kits are even coloured blue, despite the fact
they are simple halogen bulbs. Provincial governments are
responsible for do-it-yourself headlights, and also dictate the
number and power of the lamps you are allowed to stick on the front
of your vehicle. In many cases, coloured lights are outlawed, but as
we will see, the rules about lighting the road are pretty confusing.
Coming up, let’s look at the so-called fog lamps, headlight height
on bigger vehicles, and get some reader input. I’d like to hear your
experience dealing with light, either your own or courtesy of other
drivers.
Ed Drass
Email the
Traffic Guru at
edrass@nationalpost.com