5

My objective is finding a pair of glasses that would:

  • Cut the glare off
  • Be clear, so that I can see things in the night
  • Cover eyes from front and sides

I usually drive my vehicle in the night on longer trips, and I am terribly troubled by most of the ignorant drivers in the on-coming traffic, who never think to dim their head lights by cutting the high-beam for a while. Recently, some people have begun to modify their vehicles by adding HID lamps for high-beam as well, which gives some flash-bang effect on the other drivers eyes! I am looking for mostly-clear glass with the best possible polarization. The clearness or 'without being tinted' quality matters, since this is all about night driving. Polarization matters, since it is necessary to cut the eye burning glare of the high-beams.

Is there any optician or an expert who can help with this matter?

  • 6
    Polarization won't help for headlights, because headlights don't emit polarized light (in general--there are some patents for such devices, but I find no evidence that they're in use). Polarized filters, such as sunglasses, generally block reflected light (and only light reflected at a certain angle). This is why they help with bright glare off the hoods of vehicles on a sunny day, but will have no effect on light coming directly from a headlight. – Flimzy Dec 11 '15 at 10:42
  • 1
    Polarized glasses could help when driving at night in a snow storm or through fog, as the light reflected from your own headlights, off the snow/fog, and back into your face, would be diminished, granting you a greater visibility distance. – Flimzy Dec 11 '15 at 10:44
  • 3
    I'm voting to close this question as off-topic because it is basically a product recommendation question, and has been cross posted over at Outdoors, where it is also off-topic – Rory Alsop Dec 11 '15 at 10:48
  • 2
    @RoryAlsop: I wouldn't call it a cross-post so much... it was asked there, and closed (rightly) for being off-topic, and now it's asked here. That's the proper thing to do if it is indeed on-topic here. I'm not sure if it is or isn't on-topic here, but the cross-posting shouldn't factor into it. – Flimzy Dec 11 '15 at 11:24
  • 3
    I also think this is exactly the right type of "product recommendation"--it's asking if a specific type of product exists, which is objective and answerable. – Flimzy Dec 11 '15 at 11:29
6

As Flimzy explains in the comments, polarised lenses won't currently help. They reduce glare specifically from sunlight that has been polarised by atmospheric conditions and (typically) by reflecting upwards off shiny surfaces like a smooth or wet road, snow, sand, etc. They don't filter regular straight-on unpolarised light from normal headlights.

That said, in a detailed report on the problem, the AAA have proposed amongst other things making headlights emit polarised light, so that polarised glasses might be used like this. Unfortunately I'm not aware of this happening in real life, it'd be a very long time before it's standard.


There is a product category, night driving glasses, which are generally tinted amber to - theoretically - reduce headlight lights while sparing other wavelengths, but they come with other disadvantages as detailed in this article which sites published research:

...in reality, when driving at night or dusk in already limited lighting conditions, ANY tint further reduces the amount of light transmitted to the eye, and consequently, further impairs vision. The problem is compounded as the yellow tint gives the wearer the impression they are seeing better, when in fact the reverse is actually true

There was a forum thread which I can't find right now discussing this, where a skeptical person was persuaded to try night driving glasses while a passenger at night, and systematically tested what difference they made - taking them on and off, using one eye with and the other without, etc. He described how, for already-bright things like white road markings illuminated by street lights, he could see why people felt such glasses were beneficial (they were actually less bright with the glasses, but contrasted more sharply against the darkened background, so appeared to be sharper) - but everything in the greys between black and white was less visible. Basically, it made everything more black-and-white - increasing the danger of not seeing a darkly-coloured poorly illuminated hazard quickly enough to react.


If you already wear glasses, there's a product category - glasses with anti-reflective coatings - that reduce the compounding effects that glasses have on night driving vision, but these are no use if you don't already wear glasses.

The best option for night time driving is a pair of spectacles with clear lenses and an AR coating. The AR coating is beneficial in two ways. First, it minimizes internal reflections within the lenses, reducing halo problems, and second, it increases the transmittance of light through the lens to the eye. However, it is important to note, if a patient does not normally wear spectacles, AR coated lenses, or any other type of night driving glasses will not improve night vision, as AR coatings only minimize aberrations that are inherent in ophthalmic lenses and night driving glasses will simply serve to introduce those abberations to the wearer's vision.

Unfortunately there doesn't seem to be much a driver can do when traveling in an area where other drivers don't dip beams. Pretty much all the AAA's suggestions were recommendations for government infrastructure (e.g. brighter street lights) or industry (e.g. different bulbs).


I'd love to be proved wrong, though... Where I currently travel (Freetown), 90%+ of drivers don't dip beams, street lights barely exist, motorbikes with no working lights at all are common, and dark-clothed people habitually run across main roads without warning... :-( Often the only way to see hazards is by spotting silouettes in the glare.

  • Polarization is not about the angle from which the light is traveling, nor the fact that it is reflected. Rather, the sunlight that is partially blocked by polarized filters is polarized because it itself has been filtered through the earth's atmosphere. For more information, see en.wikipedia.org/wiki/Rayleigh_sky_model – phoog Dec 11 '15 at 18:22
  • @phoog whoops, I've edited that part. But my understanding is that the reflection off the specular road surface increases the polarisation, which is why surface reflections off specular surfaces are filtered more than regular sunlight. Else polarised glasses in daylight would filter everything, rather than disproportionately filtering reflected glare – user568458 Dec 11 '15 at 18:37
  • 2
    @phoog Polarization has everything to do with angle and reflection! Light from the sky is polarized to varying degrees precisely because light that's reflected at certain angles ends up polarized and light from different angles in the sky has been scattered (i.e., reflected) through different angles to be able to reach your eyes. In particular, unpolarized light that's reflected at Brewster's angle ends up perfectly polarized. – David Richerby Dec 12 '15 at 13:47
  • @user568458 Your understanding is roughly correct. – David Richerby Dec 12 '15 at 13:52

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.