# Optical Forums > General Optics and Eyecare Discussion Forum >  Polarized lenses for night driving?

## DrNeyecare

Just wondering, would you ever recommend a polarized lens for night time driving?  ie, a yellow polarized lens (to increase light transmission  yet reducing glare from headlights)

I recently tried the Drivewear lens, via a voucher given to me from my rep.  I actually like the lens.  And don't attack me on this guys, but I love this lens for night time driving.  I've been comparing it to the Teflon coated AR clear lens I usually drive with. The Drivewear lens (in its yellowish tint stage) shows much significant glare reduction compared to Teflon coated lens during night driving.  Plus, the yellowish tint does not cause noticable reduction of light that can cause a hazard.

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## CEO

Doctor, while I am very pleased that you like the Drivewear Lens, please understand that it is not recommended for night driving.  It may seem that the yellow-green color does not cut down on the amount of light, but, at 37% Transmission, it unfortunately does.  At night, the driver absolutely needs as much light as possible in order to drive safely, and I believe that tints here are not benefical, even very light yellow tints.  AR Coatings may be helpful, but certainly either polarized lenses or tints are strickly for daytime use, in my experience.

Once again, I am very glad you like Drivewear, but please limit it's use to daytime use, since it is a sunlens.

Dave Rips - President & CEO Younger Optics (maker of Drivewear)

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## cocoisland58

For dusk and dawn ie: low light conditions, yes.  For true night driving, no.  Perhaps you could get away with it in the city where artificial lighting is present but out on the country roads you need all the light you can get.

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## Diane

> Doctor, while I am very pleased that you like the Drivewear Lens, please understand that it is not recommended for night driving. It may seem that the yellow-green color does not cut down on the amount of light, but, at 37% Transmission, it unfortunately does. At night, the driver absolutely needs as much light as possible in order to drive safely, and I believe that tints here are not benefical, even very light yellow tints. AR Coatings may be helpful, but certainly either polarized lenses or tints are strickly for daytime use, in my experience.
> 
> Once again, I am very glad you like Drivewear, but please limit it's use to daytime use, since it is a sunlens.
> 
> Dave Rips - President & CEO Younger Optics (maker of Drivewear)


Dave,

Thanks for coming forward early on and setting this subject on the right path.  Great lens, but like anything else, it needs to be used for the correct visual tasks.:D

Diane

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## Johns

> Just wondering, would you ever recommend a polarized lens for night time driving? ie, a yellow polarized lens (to increase light transmission yet reducing glare from headlights)


Yellow tinted lenses transmit more light only when compared to other tints.  Any time you put a tint in front of the eye, you are decreasing the amount of light the eye is getting.  

Since vision is based on the amount of light entering the eye, we suggest an AR coating when glasses must be worn.

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## bren_03825

> Just wondering, would you ever recommend a polarized lens for night time driving? ie, a yellow polarized lens (to increase light transmission yet reducing glare from headlights)
> 
> I recently tried the Drivewear lens, via a voucher given to me from my rep. I actually like the lens. And don't attack me on this guys, but I love this lens for night time driving. I've been comparing it to the Teflon coated AR clear lens I usually drive with. The Drivewear lens (in its yellowish tint stage) shows much significant glare reduction compared to Teflon coated lens during night driving. Plus, the yellowish tint does not cause noticable reduction of light that can cause a hazard.


 
Having worn the drivewear lens once myself as it changed from dusk to night, it seemed like I could see almost just as well, and it was very comfortable, but yes it did cut down on the ability to "quickly notice" anything, especially off the sides of the road.  Living in rural Michigan, that can truly dangerous, with deer and bear.  I've recmmended to all my patients who wear tinted lenses all the time, to have a clear pair of at least dvo glasses for night driving, with AR of course.
:cheers:

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## DrNeyecare

Thanks guys!  i appreciate the clarification.  What you all said made total sense.  

Dave (CEO), yes, the Drivewear lens is a good lens.  I would say that for daytime driving conditions, I much prefer your Nupolar Grey Polarized lens.
The Drivewear lens doesn't darken enough for me.  Just my opinion.

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## bren_03825

> Dave (CEO), yes, the Drivewear lens is a good lens. I would say that for daytime driving conditions, I much prefer your Nupolar Grey Polarized lens.
> The Drivewear lens doesn't darken enough for me. Just my opinion.


:idea:

I agree with that, doc. I wear the drivewear lenses mainly at dawn and dusk, and overcast days, and gray polarized shades for sunny days. If the drivewear lens could get about 25-35&#37; darker, I would wear it full time.
:cheers:

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## BMH

Yellow at night will play with your color perception. Something or someONE on the side of the road in dark clothing at night would be very hard to see. There is a good article on LaramyK's website about the same subject. Give it a read.

my 2 cents

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## RustyS

Im not as lens savvy as some of these guys but here goes,

Polarized lens film for reducing light transmission has to be dark to get a true polar, a 10% tint on a polar will not provide enough polarization to even consider it worthwhile.

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## Happylady

I like my Drivewear lenses a lot. They are very nice for overcast, rainy weather, too.

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## ShuString

Not a great idea, Stick to the AR coating. No color tint is ok for driving at night.

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## chip anderson

Probably get best results for night driving by just cleaning your glasses and cleaning all your cabin windows _inside and out_.

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## bren_03825

> cleaning all your cabin windows _inside and out_.


Actually the best advice, clean the windows........hmmmmm, I need to do that.
:hammer:
:cheers:

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## EyeFitWell

CEO, when is poly coming?  I'm waiting to fill my voucher :-(
I'm so glad you mentioned the night driving thing at the Transitions sponsored event a couple months ago in Raleigh, Hurricanes Game.  It's logical enough to think it helps, but as a dispenser, I'm glad to know that it's my duty to warn possible consequences!

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## chip anderson

A small thing I don't remember well.  Many years ago, I had a patient bring in a pair of glasses for adjustment.  His optometrist (who seemed to know what he was doing as I did not) had selectively mirrored his "driving glasses. As I vaguely recall he had more mirror on the drivers side to reflect glare, no mirror in the exact center (maybe in a cross) and little mirror on the passenger side.
I have never seen this done before or since.

Chip

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## ilanh

Actually one night I realized that I had forgotten my regular clear glasses and the only thing I had in my car were the drivewear pair.  Not just that but I happened to be going to a wedding at the time.  I was forced to wear the drivewear glasses all night long and was astonished at how well I saw even though I was wearing fairly dark glasses at night.  There's no question that the vision was NOT optimal but it was surprisingly good.

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## Uni-Clip

> :idea:
> 
> I agree with that, doc. I wear the drivewear lenses mainly at dawn and dusk, and overcast days, and gray polarized shades for sunny days. If the drivewear lens could get about 25-35% darker, I would wear it full time.
> :cheers:


CEO, why can't you make your Drivewear darker when fully activated?  Somewhere in the literature says that it can be very dark(can't remember the transmission) but in real situation, it was never dark enough.  I was in Sydney last week and it was very bright but I think the lens only gets to about 30-25% max.  Otherwise, it's a great lens.

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## joptician

I was checking out the drivewear earlier this year and did notice that in its darkest state the transmission must have been around 12-14%.  I did not read the transmission but did compare them to a pair of brown C polars and the drivewear was darker with an excellent contrast.  I will remark that I have not tested them in the heat but if they are like the typical photochromic they may not get as dark now as they did in the winter.

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## Angel of Grace

I have been wearing my Drivewear lenses for several months.  I must admit that while out on the motorcycle i've forgot to take them off as it was getting dark.  My vision was just so comfortable in them that I forgot to take them off!  When i sell the lenses i warn the patient to NOT drive at night with them even if they feel they can see wearing them.  I'm anxiously waiting for a lined bifocal to become available with the technology.  Mr. Ceo, any input from you as to when they may be available?  I live in Florida and have a heavy elderly population to deal with and many of them just won't make the jump to PAL's.  Thanks for your input.  :D

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## bren_03825

Dave, could you PM me or send me a mail, I have a question for you, or one of your Reps in the Area?:)

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## AngryFish

RustyS, here is something to fry your brainA polarized lens is gray because it is polarized not because it is tinted.

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## AWTECH

> RustyS, here is something to fry your brainA polarized lens is gray because it is polarized not because it is tinted.


For clairification:
Actually the polarized film is tinted in most polarized lenses.  We produce a true blue polarized lens and true yellow (no gray tone at all).

We also produce a gray and a brown polarized using the same base polarized film.  The lens material is actually clear.

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## RustyS

Ok Im all ears. I have a question though.I read one of your previous posts regarding polarization and your idea for a polarized. I might get slapped down quick or i might get some good info. First off I know there are hardcore optical posters here so pardon my ham-fisted description to follow.

I'm assuming "Drivewear" is not polar and I have not seen the lens so Im not trying to dis anything here.


If i offset two polarized lenes i wanna see black and that is based on "mechanics" as opposed to tinting process so that means all polars would no matter base color are always visually appears as grey based purely on light transmission right?. I wanna have to slightly offset them to see a solar eclipse. To me that is "true polarization" I have yet to see the lighter lenses be able to even come close. I admit i have spent a few years out of the lab.   So most anything lighter than 25% would mostly dismiss as "polarizish" and a lot of these applications would be better met by a gradient (with rare exceptions)


As to not stray too far from original topic I was thinking about the PLS 530 or 540 for night driving. In flat light conditions they are fantastic. Are they still being made? I have not dispensed one in like 10+ years.

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## AngryFish

Understood that most manufacturers of polarized lenses alter the color of the filter or of the lens material; this accounts for the unnatural results of yellow, brown and various other colors and shades. My reference was to an unadulterated, polarized lens. I reference the research done by Edwin Land on color constancy that demonstrates that white light (temperature unimportant) reduced by one half nets grey light.

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## AngryFish

Rusty, to your first question, yes. To your second, some time ago I noticed the same thing. I have used what I consider to be good quality polarized lenses and they always became opaque when they were offset 90 degrees, regardless of whether they were A, B, or C but I have discovered that some of the cheap ones dont (I dont know the manufacture of the lenses and the company I reference uses them because they are very cheap) and I have wondered too, how this could be. I have until now just written it off as a poor quality polarized lens because it is not consistent from manufacture to manufacture. I have to defer to Allen on this one though he understands the process of manufacturing and may have some insight for us.

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## chip anderson

Be very, very carefull watching solar eclipse(s) back when I used to take retinal pictures, I took a few that had perfect pictures of the solar eclipse on the retina.  On the lucky ones, it took a very long time to resolve and go away.

Chip

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## RustyS

I read the read land article and immediately realized two things.

1. I understood none of it

2. The comparison pictures looked like a Andy Warhol homage.

Bu here is another question I have from the article. 

The primary prob is backlit or shaded subjects . Not being an expert here is my thought. Lets take the venetian blind theory by offsetting polarizers but this doesn't pan out for me. Then I have to revert to the pinhole. I experimented and wore  *cringe*  pinhole glasses in the eighties and directly looking at a light source would not cut intensity.  Maybe the pinholes are imperceptible and the eye the eye fills in the gaps or is that an occam's razor maybe the greeks were right in 1000bc that man emanated energy from his eyes that scenario if true would help view shaded subjects. The problem in the Land article is the same for the motion picture  industry so the problem is systemic throughout all image capture devices. We have to create the enviroment for them to perform at their best or alter the subject matter as with TV film. In comparing eyes to cameras the camera seems to be a raw nerve. I get flares or nuked out backgrounds as we all do with lets say afternoon sun coming into a glass storefront with the naked eye in this light condition no details are discernible with any subject matter too much energy input. we counter this fistly by pupil constriction then by squinting  our built in balance controls, hats, eyewear, and the either one or two handed salute to see images obscured by shadow at a distance. I will protest to there being good and bad sunwear out there but is one of the primary reasons for doing this to change the  immediate enviroment of the eye to potential subject matter as to both have lets say the same potential energy. I am not forgetting we are operating in our atmospheric soup to which we have xxx amount of years in eye evolution. When the hubble is in darkness it can take a pic of ET's butt pimple from four light years. I have to get coffee now with friend. I look forward to finding my argument shot full of holes by you sliderule guys (not a dis)

Thanks 
Rusty

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## CEO

I think RustyS forgot to take his medication today, and I would pass on the coffee today if I were you.

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## BMH

What article is Rusty refering to? I read the posting over again to see if I missed something but alas... I'm still cornfused.

:cheers:

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## RustyS

Ooops my bad wrong thread. I read the Edwin Land article on color constancy and another where they were seeking solutions on how to get a camera lens to view a shaded object without flaring. More like the human eye in its natural adaptivity. It was friday night a lot of heady incomprehensible (to me) math and i guess i cross posted. Hmmm where did that thread go???

sorry

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## optoman3

DriveWear lenses are the hands down best polarized sunwear I have ever worn.  I love them in overcast conditions and even during a rain storm.

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## specialized_jon

While not polarized, Melanin True Light offers many of the benefits of polarized lenses with a high transmission that is excellent for night driving. Melanin True Light helps reduce glare and increase contrast. As well, it has an 80&#37; transmission rate. 

Our website is currently being updated, but there is a podcast that describes the benefits of polarized and non-polarized melanin at <http://www.melanintrue.com>.

Incidentally, Melanin True is up for an OLA Award of Excellence this year along with Drivewear.

Jon Schmitt, Marketing Manager, Specialty Lens Corporation

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## Andrew Weiss

Personal experience: Late one dark and stormy night (;)), I was at a friend's house where there were no street lights and poor illumination at the fringes of the driveway.  I had only my Transitions glasses with me, and as I backed out of the driveway, I backed right into the rear end of his very dark green Volkswagen.  I tried the same manoever a month or so later with clear AR coated glasses on and noticed a discernible difference in clarity.

I'm one of those who used to use yellow-tinted glasses for night driving, but then I began to notice that they only worked well on well-lit roads.  

So this is yet another vote for the obvious (or, as my high school English teacher used to put it, "tenacious grasp of the obvious"): the better the light transmission, the better our night vision will be.

PS: I love my Drivewear sunglasses, and on a recent trip to the Inner Banks of NC my wife took a picture of me with them on and they were DARK brown!!

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## paul9718

Every body said the Drivewear is an exclent lens for driving. Anybody think that a really suitable driving lens should be slightly lighter inside but darker outside? Do you think a polarized lens with 40% transmittance inside the room and 15% transmittance out side (under sunshine) would be more confortable and suitable for driving?
With free form technology, the Drivewear could be made to be a comfortable progressvie lens up to add 3.50. Champion Fine is supplying this lenses on the market already.

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## sunglassoutlet

> Just wondering, would you ever recommend a polarized lens for night time driving?  ie, a yellow polarized lens (to increase light transmission  yet reducing glare from headlights)
> 
> I recently tried the Drivewear lens, via a voucher given to me from my rep.  I actually like the lens.  And don't attack me on this guys, but I love this lens for night time driving.  I've been comparing it to the Teflon coated AR clear lens I usually drive with. The Drivewear lens (in its yellowish tint stage) shows much significant glare reduction compared to Teflon coated lens during night driving.  Plus, the yellowish tint does not cause noticable reduction of light that can cause a hazard.


It hasn't been scientifically proven till now that why these lenses create a illusion for the drivers that they feel that they are getting a clearer vision while driving. 
As the Night Driving Sunglasses are Tinted, they reduce the amount of light entering the eye, this can cause a lot of problems while driving on meekly lit roads as it makes driving a lot more difficult.
If glare at night is a problem then i think you should opt for clear lens sunglasses or Spectacles with Anti Reflection coating which reduce glare and make driving easy.

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## Kujiradesu

> Yellow tinted lenses transmit more light only when compared to other tints.  Any time you put a tint in front of the eye, you are decreasing the amount of light the eye is getting.   Since vision is based on the amount of light entering the eye, we suggest an AR coating when glasses must be worn.


I came here to say this. ANY tint will transmit less light than a clear lens, and visual acuity will be better with a clear lens than with a tinted lens. A clear lens with an A/R coating is best for night driving if you are trying to get the most amount of light transmission possible and best visual acuity.

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## Robert Martellaro

Old thread but good topic. Step #1 is to see an eye doctor to rule out pathology and/or refractive error.

_"Yellow 'Night Driving' lenses have been shown to provide no benefit in seeing ability at night. They are even hazardous, because they give the driver a feeling of seeing better, which no one has yet been able to explain. Studies have shown that they actually impair visual performance and retard glare recovery. Many promoters have made unfounded claims for the ability of amber to improve night vision. They have employed mass solicitation, usually by mail. The Federal Trade Commission has correctly ruled that such practices are illegal since the lenses do not perform as claimed."_ - Forensic Aspects of Vision and Highway Safety", Merrill J. Allen, O.D., Ph.D., Et al.

http://www.sae.org/search/?qt=night+driving&x=13&y=6

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## Cah

still have no idea this kind of lenses are exist, but lot of my clients looking for this kind of glasses ...

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## Clear_Magenta

According to some, Polarized glasses could help in night driving when there is a snow or fog. Other option is a pair of spectacles with clear lenses.

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## Uilleann

Do NOT wear polarized sun lenses for night driving.  DO NOT DO IT.
Further, tinted lenses are also unwise for reasons well described in detail in this thread and others.

If you're experiencing glare at night, your first stop would be to the eye doc.
Second stop would be to the auto parts store for a good streak free cleaner.  The amount of dirt and film that many drivers allow to build up on their windscreens is often surprising.  Particularly on the inner surfaces.  Additionally, a good cleaning of the mirrors (all of them) and the side and rear windows will further help to reduce glare at night - sometimes dramatically.

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## Quince

I've been thinking of trying Vantage for all the time, but specifically thinking it would be good for night glare. I am very light sensitive and Drivewear has been great as a dawn/dusk or overcast/rain/snow lens. I have Maui-esque lenses for strong sun and Trans/various blue blocker coating for indoor/night use.

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## GrahamEye

> I've been thinking of trying Vantage for all the time, but specifically thinking it would be good for night glare. I am very light sensitive and Drivewear has been great as a dawn/dusk or overcast/rain/snow lens. I have Maui-esque lenses for strong sun and Trans/various blue blocker coating for indoor/night use.


Are you referring to the Transitions Vantage? The Vantage will still be clear at night as it does not have a permanent tint like the Drivewear. The polarization effect will only activate upon full darkening of the lens. The Vantage does have the UV sensitivity of the XtraActive Transitions, so it will more likely change during the day while driving. But still, not at night.

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## AngeHamm

> Are you referring to the Transitions Vantage? The Vantage will still be clear at night as it does not have a permanent tint like the Drivewear. The polarization effect will only activate upon full darkening of the lens. The Vantage does have the UV sensitivity of the XtraActive Transitions, so it will more likely change during the day while driving. But still, not at night.


Also, it is CRAZY slow at fading back to clear.

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## GrahamEye

> Also, it is CRAZY slow at fading back to clear.


Yes, the Transitions Vantage has the same fade time as the XtraActive. The number one reason why I don't sell very many Vantage is due to people wanting the turn time faster, not slower.

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## icmor

I saw a study that was done some years ago on VA at night time, and the addition of a tint.  The bottom line is that a person with 20/20 vision has a decrease to 20/32 at night.
Adding just a 10% tint on a pair of lenses decreases the VA to 20/40.  That is borderline legal to drive in most states.  A pair of glasses without A/R coating loses 8% of light transmission.  This is one reason A/R coating is recommended for night time driving.  Your patients are at risk when wearing any of the yellow driving glasses.  We refuse to sell them, and recommend A/R coat on their lenses.

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## AngeHamm

> Yes, the Transitions Vantage has the same fade time as the XtraActive. The number one reason why I don't sell very many Vantage is due to people wanting the turn time faster, not slower.


I think the Vantage is *much* slower to fade than the Xtractive. Vantage is a great product for glasses dedicated to outdoor activities, like running, cycling, hiking, skiing, etc. But for everyday use, the fade time is a deal-breaker. That said, if it ever* comes* out in hi-index, I want a pair for my Rudy Project glasses.

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## Quince

So its got a slow fade... fortunately my lenses won't be doing any actual transitioning during my night drives  :Smile:

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## Uilleann

DO NOT use polarized lenses when driving at night.  Headlight glare is NOT polarized, and will NOT be magically attenuated with a polar lens.

DO NOT use tinted lenses when driving at night.  Reduction in contrast sensitivity and visual acuity are known factors, and as was pointed out above, may well reduce a drivers vision below legal, safe minimum limits.

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## Quince

> DO NOT use polarized lenses when driving at night.  Headlight glare is NOT polarized, and will NOT be magically attenuated with a polar lens.
> 
> DO NOT use tinted lenses when driving at night.  Reduction in contrast sensitivity and visual acuity are known factors, and as was pointed out above, may well reduce a drivers vision below legal, safe minimum limits.


Why does the link in your post lead to an automotive parts supplier?

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## Quince

http://www.allaboutvision.com/sunglasses/polarized.htm

This has some good key points:

"These sunglasses can be used for driving and, in fact, can reduce glare from a long, flat surface such as the hood of the car or the road's surface." (Speaking about polarized sunglasses for daytime use. So why not clear polar at night?)

"Light reflected from surfaces such as a flat road or smooth water generally is horizontally polarized. "

"And polarized photochromic lenses, which change from dark outside to light inside, may be right for the light-sensitive person who frequently is in and out of the sun on any given day."

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## Uilleann

> Why does the link in your post lead to an automotive parts supplier?


Its an autolinking robot.  Not placed by me.  You'll have to ask Steve what that's all about I suppose, though I doubt he has any control over it either.




> http://www.allaboutvision.com/sunglasses/polarized.htm
> 
> This has some good key points:
> 
> "These sunglasses can be used for driving and, in fact, can reduce glare from a long, flat surface such as the hood of the car or the road's surface." (Speaking about polarized sunglasses for daytime use. So why not clear polar at night?)
> 
> "Light reflected from surfaces such as a flat road or smooth water generally is horizontally polarized. "
> 
> "And polarized photochromic lenses, which change from dark outside to light inside, may be right for the light-sensitive person who frequently is in and out of the sun on any given day."


There is no such thing as a "clear polarized" ophthalmic lens.  In order to function, polarized ophthalmic lenses require tint.  The more tint, the higher the polarizing efficiency.  Your link refers ONLY to daytime driving conditions with full sun.  NOT night driving.  Further, the light reflected from a road surface, or the hood of a car may well be polarized, however, at night, that is not a major source of glare.  Direct headlight glare is the #1 complaint when driving at night.  That is NOT mitigated by polarization, or tint.  Transitions Vantage - your above referenced "polarized photochromic lens", will not be activated at night, and will therefore remain non polarized.  In addition, the residual tint of that type of lens may further degrade contrast sensitivity at night.

How long have you been a tech Quince?  This is all rather basic knowledge.  Perhaps others here might suggest some good reading material concerning the polarization of light, and how the eye functions under photopic, mesopic, and scotopic visual conditions, and how visual acuity and contrast sensitivity is affected at night.  Hope that's helpful at any rate.

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## AngeHamm

The Vantage will also not activate during the day behind your windshield. It will offer you absolutely no driving benefit at any time unless you drive a convertible.

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## Uilleann

> The Vantage will also not activate during the day behind your windshield. It will offer you absolutely no driving benefit at any time unless you drive a convertible.


Agreed.  In addition, even at it's best, that lens was found to be only something like _65% efficient_ in its fully activated polar state.  Not so hot any way it's sliced.

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## Robert Martellaro

Zeiss's solution.

http://www.zeiss.com/vision-care/en_...scription.html

http://64.50.176.246/files/wavefront...cle_lenses.pdf

The Eye and Night Vision

http://www.valleyflyers.org/wp-conte...ightVision.pdf

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## drk

Uilleann is right, as usual.  He's just lucky that way.

Why on God's green earth would we use polarized lenses at night?  What light source is polarized?  Headlight reflections off of puddles in the road?  

Or is it that, somehow, plane-polarized light "scatters" less in the ocular media?  Nope.

Even if it did, you'd have to put up with contrast sensitivity reduction...LIKE THAT DEER IN YOUR HEADLIGHTS!  LOOK OUT!!!!

Yeah, G15 lenses are great when looking down the barrel of two halogen Mercedes high beams (like Chris Ryser's).  But you just killed the teenage runaway skateboarding after dark on the shoulder.  His mommy will never see him again.  And it's your fault for not knowing optics worth a darn.

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## drk

> Agreed.  In addition, even at it's best, that lens was found to be only something like _65% efficient_ in its fully activated polar state.  Not so hot any way it's sliced.


Hey, it's POLARIZED.  Didn't you get the memo?  It's P-O-L-A-R-I-Z-E-D. _  "Woo-hoo, honey, my TransAm's are polarized.  Let me do the drivin' again."_

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## drk

> Zeiss's solution.
> 
> http://www.zeiss.com/vision-care/en_...scription.html
> 
> http://64.50.176.246/files/wavefront...cle_lenses.pdf
> 
> The Eye and Night Vision
> 
> http://www.valleyflyers.org/wp-conte...ightVision.pdf


First, that Valleyflyers thing from the AOA is fascinating.

Second, I think Zeiss is full of hooey.  

What if the patient is refracted in dim illumination?  I do that, generally.  Or if they're dilated while refracted?  I sometimes do that.  They are basing their "paradigm" on their glasses being better because of wavefront?  They still can't deliver higher-order-aberration control, but they don't mention that little concern.  

Otherwise, if they want to say that a bigger pupil gives positive spherical aberration (I think the average is about a quarter diopter at most) then they can call Barry Santini for his "extra sauce" recipe.  Whoop de do.

And don't even begin with that "digital surfacing matters" stuff.  At least, not in the central optics.  

Bad Zeiss.  Bad, bad Zeiss.

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## drk

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3666881/

Good readin'.  Let's do a book report together.

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## optical24/7

Doc, have you been hanging out with Chip Anderson again?  :Eek:

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## Quince

Wow, heated....

Anyways I did specify the article was talking about daytime driving and I also specified that the idea of using Vantage was for night only. It would not be nearly dark enough during the day for me either way. I thought this was a place to bounce ideas around? Huh...

I was also under the impression that the polarized filter doesn't 'go away' or is ever inactive. I'm unclear here and would love clarification. 

I will certainly look into the links Robert posted and appreciate actual resources.


As for my credentials- should you deem them necessary- includes 5 years of self teaching and support from co-workers with much more experience than I. I am in an unlicensed state where they throw you to the wolves and if you survive with only on the job training than you tend to stay in the field. I hope that helps you understand the position of learning I am in and maybe why I'm here. To learn. Thanks for the feedback  :Wink:

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## drk

Lesson One: 

Tints are pigments that absorb light.

No tint, no absorption.



Lesson 2:
Polarized filters are pigments that are arranged (somehow) like slats on a blind (or something) that blocks, say, half of the reflections.  But you still need a tint.  They're light, because they are only about half-tinted.  Sorta.

The real explanation is that light waves (theoretical constructs) vibrate in all directions.  Think of jerking on a jump rope tied to 24/7's neck.  You can make it oscillate horizontally, vertically, obliquely, actually in all directions (until 24/7 turns blue and passes out).  That is how light vibrates.  All at once.

Now once light hits a (shiny) surface, the REFLECTION is polarized.  Only the light that was vibrating in the direction of the incident angle is reflected, the rest is absorbed.  If you orient your filter 90 degrees to this, the "slats" absorb it and block it out.  But you need tint.  Transparent blinds do a crappy job.  Like the VSP labs.

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## optical24/7

> Think of jerking on a jump rope tied to 24/7's neck.  You can make it oscillate horizontally, vertically, obliquely, actually in all directions (until 24/7 turns blue and passes out).  That is how light vibrates.  All at once.
> 
>  .


You've not seen my extremely muscular neck? A bulldog has more neck than me!  :Cool:

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## Don Gilman

> Lesson One: 
> 
> Tints are pigments that absorb light.
> 
> No tint, no absorption.
> 
> 
> 
> Lesson 2:
> ...


Whoooo! Dander up. I  LOVE IT, KEEP IT UP.

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## Quince

> Lesson One: 
> 
> Tints are pigments that absorb light.
> 
> No tint, no absorption.
> 
> 
> 
> Lesson 2:
> ...



I've heard about the slat formation but didn't realize it needed the tint to be effective. Your explanation was informative AND comical. That's how I learn best!!

So we make polarized lenses 90 degrees off to counter that polarized light- does that mean that all polarized light is traveling at the same angle?

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## Uilleann

> Wow, heated....
> 
> Anyways I did specify the article was talking about daytime driving and I also specified that the idea of using Vantage was for night only. It would not be nearly dark enough during the day for me either way. I thought this was a place to bounce ideas around? Huh...
> 
> I was also under the impression that the polarized filter doesn't 'go away' or is ever inactive. I'm unclear here and would love clarification. 
> 
> I will certainly look into the links Robert posted and appreciate actual resources.
> 
> As for my credentials- should you deem them necessary- includes 5 years of self teaching and support from co-workers with much more experience than I. I am in an unlicensed state where they throw you to the wolves and if you survive with only on the job training than you tend to stay in the field. I hope that helps you understand the position of learning I am in and maybe why I'm here. To learn. Thanks for the feedback


You bounced - we bounced back.  All part of the learning process eh?  :)  You're asking questions - which is the most important thing you can do.  Followed immediately, of course, by listening to the information you get from asking.  I asked if you were new as we were ALL new at this game once upon a time.  Some of us with rather more time than others!  I've only got about three decades in the ring myself, and am always learning new things.  Keep ravenously asking questions like these, and taking the answers to heart, and you'll do just fine - license be damned.

As for the Vantage lenses at night - nope, not gonna work.  Without the tint, there is no polarization.  And again, the illumination we experience at night is not the same as under daylight.  Even the very best polar lenses, under the brightest sun, only remove a small portion of reflected horizontal glare.  The majority of the 'work' of any sun lens is in the overall reduction of light intensity (not just polarized rays) across the visible spectrum (accepting of course the variations between different base tint colors, and of course mirrors if present).  Polar lenses are very nice, but the effect is much more subtle than overt in 95% of daylight scenarios.  

It sounds seriously silly...but the best thing 99% of drivers at night can do is clean the inside of your car's glass.  Get rid of the film, and watch your night glare from point light sources drop off a cliff.  Cleaning the outside is important too of course, but the insides of the majority of windscreens are filthy.  I can confirm this with even new cars, as well as used and abused cars after detailing them for a good number of years.

You know that green nose cheese you pull off nose pads and arms?  I've seen even worse come off the inside of auto glass.   :Eek:  :Smug:

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## Chris Ryser

Uilleann is right down to the point.

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## Paul Smith LDO

> You bounced - we bounced back.  All part of the learning process eh?  :)  You're asking questions - which is the most important thing you can do.  Followed immediately, of course, by listening to the information you get from asking.  I asked if you were new as we were ALL new at this game once upon a time.  Some of us with rather more time than others!  I've only got about three decades in the ring myself, and am always learning new things.  Keep ravenously asking questions like these, and taking the answers to heart, and you'll do just fine - license be damned.
> 
> As for the Vantage lenses at night - nope, not gonna work.  Without the tint, there is no polarization.  And again, the illumination we experience at night is not the same as under daylight.  Even the very best polar lenses, under the brightest sun, only remove a small portion of reflected horizontal glare.  The majority of the 'work' of any sun lens is in the overall reduction of light intensity (not just polarized rays) across the visible spectrum (accepting of course the variations between different base tint colors, and of course mirrors if present).  Polar lenses are very nice, but the effect is much more subtle than overt in 95% of daylight scenarios.  
> 
> It sounds seriously silly...but the best thing 99% of drivers at night can do is clean the inside of your car's glass.  Get rid of the film, and watch your night glare from point light sources drop off a cliff.  Cleaning the outside is important too of course, but the insides of the majority of windscreens are filthy.  I can confirm this with even new cars, as well as used and abused cars after detailing them for a good number of years.
> 
> You know that green nose cheese you pull off nose pads and arms?  I've seen even worse come off the inside of auto glass.


Brian, some of us cover our face with our hands when we sneeze while driving.  It's the passenger seat you got to be worried about.  Hey, that's not a fleece seat cover your sitting in.

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## Chris Ryser

> *Uilleann is right, as usual.  He's just lucky that way.
> 
> Why on God's green earth would we use polarized lenses at night?  What light source is polarized?  Headlight reflections off of puddles in the road?  
> 
> ................................
> 
> Yeah, G15 lenses are great when looking down the barrel of two halogen Mercedes high beams (like Chris Ryser's).  
> *



Yes Villeann is right, and you drk, is nearly right, but a bit off key.

No Mercedes.
I own 2 "Town & Countries" and have an old Cady SRX, 2006 in my garage in Naples, FL with now 31,000 miles on the clicker.(still looks like new inside out).

Besides that G15 lenses absorb over 70% of visible light, you would not use them at night on a highway with tons of barrels of halogen lights on Mercedes or other cars coming at you.

When still working for fathers store in Switzerland years ago, we used to sell yellow lenses with a 10 mm square mirrors, just de-centered, so you could move your head and deflect those bothering headlights, and there was no halogen lights then.

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## Quince

> You bounced - we bounced back.  All part of the learning process eh?  :)  You're asking questions - which is the most important thing you can do.  Followed immediately, of course, by listening to the information you get from asking.  I asked if you were new as we were ALL new at this game once upon a time.  Some of us with rather more time than others!  I've only got about three decades in the ring myself, and am always learning new things.  Keep ravenously asking questions like these, and taking the answers to heart, and you'll do just fine - license be damned.
> 
> As for the Vantage lenses at night - nope, not gonna work.  Without the tint, there is no polarization.  And again, the illumination we experience at night is not the same as under daylight.  Even the very best polar lenses, under the brightest sun, only remove a small portion of reflected horizontal glare.  The majority of the 'work' of any sun lens is in the overall reduction of light intensity (not just polarized rays) across the visible spectrum (accepting of course the variations between different base tint colors, and of course mirrors if present).  Polar lenses are very nice, but the effect is much more subtle than overt in 95% of daylight scenarios.  
> 
> It sounds seriously silly...but the best thing 99% of drivers at night can do is clean the inside of your car's glass.  Get rid of the film, and watch your night glare from point light sources drop off a cliff.  Cleaning the outside is important too of course, but the insides of the majority of windscreens are filthy.  I can confirm this with even new cars, as well as used and abused cars after detailing them for a good number of years.
> 
> You know that green nose cheese you pull off nose pads and arms?  I've seen even worse come off the inside of auto glass.



I'm ALWAYS asking questions! That's actually why I switched to the lab from being hired for retail. The science and ever changing tech is the best part... well, besides buying frames.

And you are right about the windshield. I've had to replace mine twice on a car three years old. Everytime, I see it as a blessing in disguise because of the clarity. I recently cleaned mine, but then decided anti-fog spray would be a good idea. Sure keeps the glass defogged, but also mucks up my once streak free shine. Sometimes you can't have the best of both worlds.

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## Uilleann

> I'm ALWAYS asking questions! That's actually why I switched to the lab from being hired for retail. The science and ever changing tech is the best part... well, besides buying frames.
> 
> And you are right about the windshield. I've had to replace mine twice on a car three years old. Everytime, I see it as a blessing in disguise because of the clarity. I recently cleaned mine, but then decided anti-fog spray would be a good idea. Sure keeps the glass defogged, but also mucks up my once streak free shine. Sometimes you can't have the best of both worlds.


Yes, the glass is often a major culprit of glare.  Autos are very bad more often than not - and you're right as well that many of the anti-fog treatments do leave a residue or film on the glass.  No fog, but the trade off is likely more glare.  Aircraft windscreens are tricky as well, and while many of them don't have the same film build up inside, fogging can be an issue.  And of course there's all the bugs, birds, and martians you have to keep scraping off the outside that make for an *exciting* time shooting short finals at night!  :)

There is also the other glass to consider...the eyeglass.  Just like the car, we all know that the majority of the glasses we see come across our desks are filthy, scratched, covered in paint, hair spray, bodily fluids, mystery sauces...its a wonder some people see at all!  Cleaning of all optical surfaces is the best first line of defense to combat glare at night.  After that, a high quality anti glare lens.  And of course, regular annual visits to the eye doc to maintain optimal comprehensive ocular health.

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