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Originally posted by charley:
Sorry to burst your bubble, but sunglasses will block all forms of light, and polarized sunglasses will do even worse.
The point of polarized lenses is to selectively block some light more than other light. As they apply to daytime conditions, polarized lenses tend to block light from surface glare much more than they block other light, because surface glare tends to be mostly polarized horizontally, while most other light tends to be equally distributed among all angles of polarization. Thus, by blocking horizontaly-polarized light, you block most surface glare, while blocking a much smaller portion of other light.
My idea is based on the notion that if direct light from headlights (which is the main source of night time glare) were polarized horizontally, then drivers wearing vertically-polarized sunglasses would have much more of that undesirable light blocked from entering their eyes, while having a much smaller portion of desired light reflected entering their eyes from things they need to see.
Hyster E60XM-33
1996 Mercury Mystique GS, Zetec, ATX
To email me, remove the string HatesSpam from this address:BobHatesSpam@Blaylock.to
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how about avoiding this whole idea and buying night vision goggles that have selective programming to block out certaain lite!  
95'Contour GL 2.5L (JUNKED!)
~~~
[Current Car]
1995 Ford Mustang 5speed
[Upcoming Car]
2002 Trans Am WS6 (Black on Black)
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Blue has the worst qualities of all the visible light. Actually, violet would probably be worse, but there is so little produced by a halogen bulb you cant really count it. So, assuming that, if you remove blue light from the lamps, you have yellow, or more specifically, selective yellow. The French required this on all cars up until the early `90s. To my knowledge there have been no actual tests proving yellow is better on a normal road then yellow. The yellow light would throw off the colors of the surrounding objects so that could be a problem to some drivers. However, putting any kind of a filter over a bulb will reduce light output so for visibility, that is bad.
Now, back to normal bulbs (HID, HIR, or halogen) what will you get if you take all the light that is escaping above the center of the lamp and put it down on the road? Doing this will reduce the reflectiveness of overhead street signs. However, you will have more on road visibility. Plus, if you arent letting the light above center, you can run brighter (HID, HIR or H9 halogens) bulbs and not dazzle the oncoming traffic with your glare.
Removing the light above center is what the rest of the world has done, leaving us in the dark, so to speak. E-Code lamps, JDM if your on the other side of the road, or a harmonized beam pattern is perfect for doing just this. IMHO, the only drawback to these beam patterns is to oncoming traffic under certian situations. Picture yourself driving along a dark, two lane road. Coming towards you, in the other lane, is a HID powered BMW. Your eyes are adjusted to the lack of glare coming out of the BMW. The driver of the other car goes over some train tracks, and for a breif instance, you find yourself under his cutoff. You will be temporarily blinded, but just for a fraction of a second.
I have a few pics showing exactly this. I have more, but they are on the other computer and I dont want to go sign it on right now. PM me if you want them.
In front of the car, above the cutoff, oncoming traffic will see this:
Notice how the snow doesnt light up until it falls below the 25" high cutoff? This makes driving more pleasant in snow or heavy rain. Your light doesnt have a chance to bounce off of the water droplets or snowflakes and come back and blind you.
But, imagine youself in the scenario I mentioned before. This is what happens. Granted it is an extreme because the camera is on the ground. Most vehicles dont have four H9s lit up while the car is in motion either.
Those beam pics are basically what each and every one of Milans buyers are experiencing now. I went a slightly different route to fit them onto my pre-98. Milans customers dont have the same housing that they are using for their lowbeams in the foggie position either.
You can find more info about what you are mentioning here:
http://lighting.mbz.org/, specifically the blue bulb section. http://faq.auto.light.tripod.com has a great amount of info as well. I dont have the link to the Philips forum right now, but I can post it later if anyone is intrested.
Long winded., but with 3x more light output then a stock Contour, I can be.  
EDIT: Oh, and polarizing the beam isnt the best idea. Good in theory, but not in performance. Light is exiting your housings at all different angles. If you only allow the light that is, say 30 degrees from the center axis to escape you will be putting on blinders. You would have no foreground (the light that uses the top of the reflector) and your long range and overhead (stupid DOT) will not exist.
Last edited by ExDelayed; 04/07/03 11:08 PM.
· Jon Miconi
· Coming Soon!
· 01 Cougar
· 98 V70R
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Originally posted by Bob Blaylock:
There's this idea that occurred to me a few days ago, that I've been wondering about ever since.
I'll start by talking about sunglasses. In their simplest form, sunglasses are merely darkened lenses that reduce the amount of light entering the wearer's eyes. If there's too much light, such sunglasses can increase the wearer's comfort.
A slightly more advanced approach involves coloring the lenses, on the theory that undesirable light (glare) may be predominently in some color bands, while desirable light may be in others, in order to increase the ratio of desirable light to undeisrable light, and thus improve not only the wearer's comfort, but his ability to see what he needs to, among the glare.
The pinnacle of sunglass technology, of course, is polarization. It turns out that most surface glare is horizontally-polarized, so wearing sunglasses that are polarized to block horizontally-polarized light, while freely admitting vertically polarized light, offers the greatest ability for the wearer to see what he needs/wants to see, while blocking the most glare.
I was recently thinking about night driving. At night, the primary source of light by which you see is your own car's headlights. The primary source of undesirable glare is direct light from other cars' headlights.
I was wondering; what if car headlights had polarizing filters over them that admitted only horizontally-polarized light, while drivers wore standard vertically-polarized sunglasses? Direct light from oncoming cars' headlights would be blocked from entering one's eyes, but reflected light from your own headlights would be scattered and depolarized, as it bounces off of the things that you need to see, so your own ability to see what you need to see would not be nearly so impaired. (i've just performed an experiment invoving a polarizing filter over a flashlight, while wearing polarized sunglasses. As I expected, polarized light from the flashlight was, in fact, mostly depolarized as it was reflected off of various objects.)
The obvious down side of this is that wearing sunglasses at night would reduce the amount even of desirable light entering your eyes. It seems to me that making the polarized headlights brighter could compensate for this, and that in any event, that the advantage of not being blinded by oncoming headlights might be greater than the disadvantage of having even desired light reduced.
What does everyone think of this idea? Good idea? Bad idea?
I guess putting it into effect would be the difficult part. Assuming it doesn't run afoul of any vehicle regulations, anyone could put polarizing filters over their headlights, and wear polarized sunglasses while driving at night, but this wouldn't really help unless everyone was doing it. Obviously, headlights would need brighter bulbs to begin with, so that the light remaining after the polarizing filter would be in the same amount as normal unpolarized lights. You'd probably want them even brighter still, to compensate for the losses in drivers' polarized glasses, but you wouldn't want to make that adjustment until it could safely be assumed that most drivers were wearing such glasses.
Last time I looked into this -- many years ago -- in urban areas where many light sources are present, lenses with a blue tint improved night vision.
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Originally posted by Drumbo:
Last time I looked into this -- many years ago -- in urban areas where many light sources are present, lenses with a blue tint improved night vision.
Blue light triggers reflectors better then other colors. So, you would see signs, license plates, etc easier. However, if it strays over into oncoming traffic the eyes of the other driver dont adjust as good to blue as other colors, creating glare. When you get into unlit, rural areas the blue will give you a headache from eye strain. Coating a bulb, especially a halogen, will reduce its total output as well. Expect roughly 800-900 lumens from a blue tinted bulb (Silverstars, CoolBlues excluded) where you would have roughly 1100-1200 from a regular bulb.
· Jon Miconi
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I once saw a group of marketing pictures from a company that outfitted commercial trucking fleets with a ultra-violet projector lamp
The high frequency of the untra-violet light allows it to penetrate deeper into fog, snow and rain than light from the visible sectrum. Its benefits come at times of low visibility such as fog, rain or snow. It showed 2 photos, both in an environment with a simulated fog cover and visibility of 100 feet. 1 was with conventional lights, the other with conventional lights plus the UV light.
Placed at 100 feet were an orange road cone with reflecive tape, a green reflective interstate highway sign and a person wearing a white shirt and a reflective traffic vest.
In the picture with conventional light all you saw was the white glare comming from the fog. In the picture with the conventional lights plus UV light all 3 objects showed up, the road cone looked like a road flare, the sign looked like a neon sign and the person looked like a white shirt and a traffic vest hanging in mid-air.
I feel sorry for the people who don't drink. When they wake up in the morning, thats the best they're going to feel all day - former President Lyndon B. Johnson
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