"In real life", pre-"electrochromatic mirrors" cost hundreds of
dollars. Not cuz today's mirrors are expensive for the EM technology,
but cuz they mold the damn things into the body instead of jes making
it a bolt-on attachment. Heck, EM welding helmets can be had fer $39!
So, why do non-EM sunglasses cost $300!? Don't get me started......
Because people buy them. Subaru has another gadget. It has compass
embedded in rear view mirror red letters E, N, W, S, etc. after few
years the letters don't light up needing to replace the whole mirror
which is expensive. CVT has two solenoids molded in one with
one connector. If one goes won't shift. Have to replace the whole
assembly costing like 1500.00. Usually goes right after warranty runs
out. Look at those people lining up at the store trying to get their
hands on new iPhones. It is all our fault......
The height of the lamp isn't the issue. As you noted, it's the aim point and the
coverage area. Misaimed headlights are frequently too high and stray into the
They aren't. The DOT regulates how bright a standard headight can be.
Table XVIII and XIX - note the Maximum Photometric Intensity column. People
think High Beams means brighter - it doesn't. It means the aim point is higher.
People also think some lamps are brighter because the color temp is different -
more blue than incandescent or halogens. That's also regulated, but not as
There are two different issues at play. One is left to right aiming:
the driver's side (inner) headlamp is supposed to point "right" instead
of straight ahead. This keeps your lights out of the "other lane".
But, height/elevation also plays a role. If you're lights are higher up
off the roadway, they will cross a given point of elevation that lower
mounted lights won't. E.g., an 18-wheeler's lights are more likely to
be up *above* my eyes, pointed downward, than a MiniCooper's.
In each case where "oncoming" drivers "flashed us", they were parked
(at a light) directly across the intersection from us. I.e., close
enough that our light cone hadn't fallen to a point BELOW the driver's
Living in a world of pickup trucks, we had noticed this early on:
"Why are everyone's headlights so bright?" But, you'd only notice
when the offending vehicle was very close -- not "down the road a
bit and headed in your direction". The "solution" is to get your
vehicle *up* and out of the downward aimed lights sooner.
Exactly. "High" and "low" aren't synonyms for "bright" and "dim".
Properly aimed, they should not be blinding others no matter how bright.
One possibility is some drivers just see they are brighter and assume
you have the high beams on even if they are not blinded.
Possible aim is bad from the factory. Unlikely, but stuff happens.
The factory specs are less than the best. I sometimes do notice the
Jeep SUV type is a bad aim for oncoming cars. I see a couple of them
and they are brighter in my eyes than any other car.
Another possibility is you have 6 bags of concrete in the trunk and the
lights are looking up. Many cars have self leveling lights though.
See my other posts, here. The issue is elevation of the headlamp.
The first time it happened, we (new to the car) went to "lower"
the beam -- and ended up flashing the highs, instead. So, the
other vehicle now *knows* we didn't have the highs on.
Had he been in a pickup truck or other "high riding" vehicle, he
would probably not have noticed. Or, had his vehicle been
in relative motion to ours so he wasn't in the "bad spot"
for the duration of the traffic light.
It's also possible that seeing the "wider" light source (3 lamps
each side instead of just one filament) led him to think it was
two bulbs, side by side.
And, they're "whiter" than normal incandescents.
There's a real spare in the trunk (instead of a bottle of sealant and a
pump) but I doubt that makes much of a load difference (~100#?)
Think about what you've said. Now, take out a piece of paper
and a ruler and draw your "solution". Better yet, cite the actual
ordinance so you know you're drawing the right elevations, spacings,
Tell me how car height "does not matter" -- to the geometry involved?
In most states, car headlights have to be between ~24 and ~54 inches
"above grade". The ROOF of *my* car (not SWMBO's vehicle which I've
been talking about) is LOWER than that! So, my *eyes* will be even lower,
Please tell me what sort of "angle" those "higher cars" could adopt
to keep their lights OUT of my eyes? Perhaps pointed STRAIGHT DOWN??
Headlamps are not point sources. Nor are they highly columnated
(i.e., the light cones *disperse* else they'd be pretty USELESS
at illuminating the roadway ahead -- you'd only be able to see
two *points* on the road at some fixed distance ahead!).
Roads are not level. The person some distance in front of you may be
at a higher or lower elevation; and, the roadway on which you (or he)
are situated may be inclined (pointing lights upward or downward).
The distances between vehicles (light source and incident surface)
I'm eager to hear of the revolutionary geometrical principles you've
uncovered that ENSURE *legally* conforming lights can't shine in
another driver/passenger's eyes! :>
Play with someone else.
If folks are flashing lights at you, something is wrong at your end.
On a level road, there is a point where the central beam is to hit the
road. I don't know the exact feet it's supposed to be. If you set it
20 feet further out (aka higher beam) you blind other drivers
unacceptably. This point of hitting the road x feet ahead, does not
change based on vehicle height. Only the angle of the lights changes
based on height of vehicle.
It's really basic middle school geometry level stuff.
No. You refuse to acknowledge that the world doesn't consist
solely of flat roadways, divided highways, rational drivers, etc.
When I leave my subdivision, I am pointed uphill. At the crest
of the hill is a light. Traffic coming *towards* me is ABOVE me.
Simple geometry (ray tracing) suggests the centerline of my
headlights will *climb* with respect to the other car's
elevation as long as the uphill slope of my roadway exceeds
the ~2 inches per 25 ft that my headlights are intended to
If my headlights are already "high up", then they've got a head
start in their journey to the opposing driver's eyes.
Opposing driver is in his left turn lane. I am in my left turn
lane. MY HEADLIGHTS WILL SHINE DIRECTLY ON THE FRONT OF HIS
VEHICLE. Neither of us are on "the wrong side of the road".
Yet, my body is "farther left" than *his* body! I.e., my
RIGHT headlight can hit him square on just as easily as
We're both *stopped* in these positions -- and will remain so for
the better part of a minute. Unlike if we were *traveling* in
opposing directions. So, we each have plenty of time to notice the
other's lights in our eyes.
As mine are closer to points of light (than a traditional, large
"sealed beam" light that spreads the light out *before* it
leaves the reflector), mine will appear brighter. As mine
are three individual point sources side by side, he can
mistakenly think of them as "multiple bulbs" -- instead of the
single "lighting element" that they represent.
Draw a little picture. "It's really basic middle school geometry
As I said, if we had a "problem", folks would CONSTANTLY be flashing
their brights at us. Coming face to face with a police officer
should result in an instant citation, right?
All you have to do is IGNORE my posts and you won't see them!
Gee, isn't that wunnerful?
I think I'll go toalk to the sheriff tomorrow. Be nice to
KNOW I'm right. And, see how folks can so blindly exhibit
(Occam's Razor. Easier to believe factory built car wrong? But,
only *some* folks notice it and alert us to that? Or, that
those same folks get light caught in their eyes and have only
one instinctive reaction: flash their high beams? I bet you
believe 9/11 was a massive CIA conspiracy, too! :> )
Implementation is for lower life forms. <g>
I propose that everyone traveling west to east wear polarized glasses and
cars traveling from east to west have lights that are polarized in a
different plane. (sarcasm alert!)
I just read http://www.danielsternlighting.com/tech/aim/aim.html
Nomatter the height of the light there is a small trgt range to hit at
the 25' distance. Another factor is horizontal aim, but some desighns
have little control over it.
Although you state the light is not comumner, the desighn does limit the
amount of light beamed to the left of the car so it does not blind the
And that target area is RELATIVE TO THE HEIGHT OF THE HEADLAMP, not
the ground! I.e., a headlamp located 30 inches above grade will
"hit the roadway" farther away (from the headlamp) than a headlamp
located 25 inches off the roadway. So, "car height matters".
And, the resulting downward angle is almost immeasurable: 2 inches
over 25 feet. A roadway with a 1:150 slope would be comparable
(i.e., practically indistinguishable from "flat"). As such, if
your vehicle is on even the slightest of upward roadway slopes,
the headlamp "beam" will CLIMB as it leaves your vehicle. If
another vehicle is directly in front of you (as in two opposing
vehicles each in their respective COINCIDENT left turn lanes)
then your lamps will shine directly into the other driver's
eyes. And there's nothing you nor the factory nor the dealer
can do about it. "Simple geometry" :>
And some designs have no independent control over the "high" element.
Conventional headlight designs have one bulb with two filaments
and/or two bulbs. I.e., two physical light sources which can potentially
be adjusted independently of each other.
In our case, there are *5* light sources in each headlamp; three
for the "low" beam and 2 for the "high" beam. Without even looking
at the car, I can safely state that the two "highs" are not adjustable
independently of each other. Nor are the three "lows". Doing so would
add far too much labor to what should be a trivial manufacturing
task ("insert headlight assembly") -- having to make *10* adjustments
just to ensure all 10 elements (2x(3+2)) are pointed in their correct
The role of the *optics* is to constrain the beam's dispersal pattern.
Otherwise, light exits the "lamp" in an uncontrolled manner. A laser
is the typical example of highly coherent light -- it *all* goes in one
tight, narrow beam. There's no "splashover" in unintended directions.
Headlamps that resolve to *points* at long distances would be
completely impractical. They wouldn't show you more than "two
particular points" on the roadway from any given car position
and orientation. Imagine fastening two laser pointers to the
front of your vehicle... *But*, they wouldn't venture astray and
end up in another driver's eyes! :>
So, you want to allow the headlamps to cast a wide beam -- without
crossing a line into "oncoming traffic". (assuming, of course, that
your car isn't POINTED into oncoming traffic due to the geometry
of the roadway, etc.)
The optics on the five "bulbs" in each of our headlamps differ
based on the intent of the light they emit. The 3 "low beam"
emitters (towards the outside of the vehicle) are almost
(hemi)spherical in appearance. They look like 1.5" glass BALLS!
The actual emitters (LEDs) are located directly behind them -- pointing
forward THROUGH these globular lenses.
By contrast, the 2 "high beam" emitters are located *below* the
"bulbs" (loosely speaking... "the points at which the light appears
to exit the headlamp"). They face SKYWARD! Instead of a globular
lens, they shine into a curved mirror, of sorts, so the light
takes a right-angle turn as it leaves the headlamp. No doubt, this
allows the light greater leeway in its path forward.
Best think in terms of inside/outside -- you want to orient the
light field from the headlamp(s) towards the roadside instead of
towards oncoming traffic.
Yes, the same design that limits the light in the other guy's eyes on a
two lane is the cause of the potential blinding when head on. Can't
I imagine the entire assembly can be aimed, but there is no need to do
them independently. The factory design should be fixed so they all aim
in the proper direction and no need to move just one. Most likely they
are in a molded housing.
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