I think I was blessed with a tad bit of night blindness so during my mis-spent
youth of night time high speed raiding I got a lot of experience with
headlights and driving lamps.
The federal history of automotive lighting is pretty depressing. During the
60s there was a wealth of European manufacturers building high quality
headlamps, all of which were ilegal in the US. The DOT didn't trust US
citizens to dip their lights appropriately and the US lamp manufacturers made a
pretty effective lobbying effort to prevent foreign technology from getting a
toe hold. Quartz Halogen headlamps made by such companies as Cibie and Sev
Marchal were illegal to install, although they were available. This made many
of us sports car nuts criminals, as we thumbed our noses at the politicians and
gendarmes in our little sports cars with hot head lights. (oh well it was a
bit romantic at the time)
For this reason we got 4 tiny headlamps in the XJS and Rover SD1 instead of the
cool Eurospec units designed around modern bulb, reflector and lens technology.
During the 80s there was no stopping the higher efficiency of the halogen
bulbs, so standards were relaxed to allow halogen bulbs to be legally available
to the US motoring public. But the lobbyists got their punch in, Halogen bulbs
could only be sold in SEALED lamp units. With one swift slash of the political
pen the playing field had been leveled allowing Westinghouse and company to
design, build and sell old fashioned technology sealed housings, but now with
halogen bulbs installed. Suddenly we had brighter lamps, but with the same old
reflectors and lenses, a real step forward. Not to mention when the bulb
failed, you had to throw away the whole lamp assembly which did nothing to
forward the cause of high quality optics. The only European manufacturer to
come to the plate was Cibie who introduced a sealed lamp enclosure with high
quality optics that had a pocket at the back to accept a replacable H4 bulb.
Thus showing that the French were smart enough to bend the laws even if they
wouldn't let the British do the same thing at Le Mans.
Finally I believe we have the automakers to thank who figured out if they made
the lamp assemblies unique for each car they could sell lots of expensive high
quality optical units through the crash repair aftermarket. I don't think
Westinghouse et al were very happy about this idea, but I think it indicates
who has more political clout. I do have a sinking feeling that there was some
kind of agreement that the manufacturers would undersize the wiring in their
vehicles so that the replacement bulbs made by Westinghouse et al would burn
out more often. I've no proof, but for some reason the operational life of all
bulbs in current US vehicles seems to be very short.
So we have a grand conspiracy, a government with no trust in the common man,
criminal sports car drivers and an on-going battle of the optics.
Now don't get me started on rear fog lights, but every time I see some idiot
driving on a clear night with the &*$(^&%&%* rear foglights on, I realize that
perhaps the government was right not to trust us.
Now I had better get back to work.
TTFN
Kelvin.
> > I thought sealed-beam halogens died a well-deserved death
> around 1980
> > or so. The only advantage they have is they're brighter,
> which means
> > inflicting oncoming drivers with more blinding glare because the
> > crummy Coke-bottle lenses have no effective cutoff pattern.
>
> David, I think you may be a touch confused. Sealed-beam simply means
> that the bulb and lens/reflector are replaced as a single unit. The
> halogen version has a halogen bulb inside. These are still readily
> available as replacement items for cars orginally fitted with them.
>
> In the US, bulbs like the H4 with seperate reflector/lens
> didn't really
> take off until the federal regs changed, and you started seeing
> 'composite' headlamps on new cars. Cars like the MG with standard 7"
> round lamps can be fitted with Cibie, Wipac, or other units
> with a bulb
> of your choice. Or you just spend $7 on a new sealed beam
> halogen when
> the existing ones burn out.
>
> The lens pattern is more a result of federal regs than
> anything else, so
> while a US-spec Cibie or Wipac will be an improvement over
> the standard
> lamp, if you want a good pattern and cutoff, you need to get E-code
> lights. They are, of course, technically not legal for road
> use in the
> US, but given the fact that they won't dazzle other drivers,
> and there's
> such a wide variety of headlights out there these days, it's
> unlikely to
> cause any problems.
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