From: Johann Schubert <jes@hpamsh4.ptp.hp.com>
Date: Mon, 9 Oct 1995 15:52:38 -0400

REAL AUTOMOTIVE LIGHTING:

The US is basically in the dark (pun...) in regards to automobile 
lighting. From WWII to about 1980. We have had the same lights. A 
sealed beam built from corning glass. The mirror finish of the reflectors
are poor as are the optics of the lense. The result is a light with
hot spots on high and low beams and stray light everywhere except where
you need to see. An "improvement" was made in 1981. Halogen bulbs were
placed inside the sealed beam. The result is the same poor quality lamp,
but brighter! In 1986 the US decided to allow composite lamps, however
no changes were made in the area of beam pattern. Most composite lamps
are plastic! The original bulbs were 55W/60W. As a result of poor
optics these lights were considered too blinding and the bulbs where
reduced to 45W/60W(?)! The obvious solution would be to improve the
optics.

Meanwhile the rest the western world (Europe in particular) had left us 
in the dust by at least 1970! H4 headlights, both composite and sizes
similar to the sealed beams used in the US were widely used. The major
difference between the H4 lamp and a US spec sealed beam is the 
construction. Most H4s and composite Euro-code lamps use a polished
metal reflector and a lead-crystal lense with a replaceable H4 (Halogen)
bulb. Some companies (like Cibie') even checked their lenses with a 
laser for optical accuracy. The result is low beams with more light on 
the road and less in the oncoming drivers eyes and truley impressive 
high beams.

So the point of my lengthly post is:
   Why doesn't the DOT adopt Euro-code lighting standards? The only 
   argument of the past is now moot, that was that the H4 lamp is not
   sealed and a person could touch the relector and lense. (now possible
   with any DOT composite lamp...) If the manufacturers are too cheap,
   then at least give the motorist the option of switching. (I believe
   Canada allows Euro-code lamps) IMHO the biggest problem is lobbying
   by the likes of GE and Wagner, who are afraid of foreign 
   competition...

Comments with those trying to improve their DOT composite lamps:
   PLEASE, PLEASE don't install a set of the high powered bulbs that
   companies are selling in the back of car magazine! If these bulbs only
   affected the high beams, it wouldn't matter, but the things I have 
   seen are 85/100W bulbs and others more outrageous. For those of
   us coming the other way this creates a seriously blinding set of
   lights. Try adding a quality set of auxilary driving lights or fog
   lights (properly adjusted) instead....