schwettynuts

This is kinda funny i think. I bought a brand new pair of polarized sun glasses last night. Today I was ready to drive my tc with my new glasses. Suddenly I see white spots all over my windows. I was so ____ed. I told my wife about it but she did not notice it. As it turned out, it was because of my polarized sun glasses. It makes you see stuff that your eyes cant see. I was ready to go to the dealership and complain. Has anyone notice what I was seeing?

Kwiksilver

i've noticed the circles on the rear window, but they are in a uniform pattern, so it is normal. plus lots of others have seen them too. is that what you mean, or were they randomly scattered or something?

O5_TRD_tC

my friend wore polarized shades in my car too and he saw the dot also. So your not alone. :D

thescone

In simplest terms, polarized sunglasses will only let in light that is coming straight at you, light arriving at different angles will be blocked, thus you see the white spots. If you have revos you will see this on the scion and on some windshields that having polarization applied to them will appear darker
(cadillacs). My father was a B-52 pilot and he told me that airforce issued sunglasses we not polarized, due to the fact that B-52 windshields were already polarized, thus avoiding the effect you are observing.

schwettynuts

Yes, but you can only see it if you have polarized glasses.

Kwiksilver

i'm able to see them without any sunglasses or glasses of any kind on. weird. but only on the back window, but still weird.

clear_bra_guy

the spots you see on the glass are tempering marks from when the glass was baked in the kiln to temper it. basicly the glass is lowered in a chiken wire basket hence the little circles are the area that cooled faster having no contact withth wire
class dismissed

bubblemyster

I want xray vision glasses to see in uhmm....

Rivulent

Yep, it's polarized. UV protection probably? I see a lot of newer cars have the same effects when I put my shades on.

Streeter

heeeeey nice picture

lowrightor

Other than the white circles, do you guys recommend polarized glasses?

Tomas

Back in the '60's when I was SCCA racing we NEVER wore polarized lenses because of the chance of having those abberations make us miss something important outside.

What you are seeing in the glass is mostly stresses, and in fact one way we used to look for sresses in optical materials was to put a polarizing sheet on both sides , shine light through the sandwich, and rotate the polarizers relative to each other. One could even find insipient cracks before they started...

As an example here are some polarimeters that use this technique:

polarimeters (.pdf - 736K)

(The 'polarimeters' we used back in the '60's and 70's were, uh, a lot more crude...)

What happens is the stresses in the glass 'twist' the polarization of the light coming through it, and when viewed through a polarizer (like the sunglasses) one gets to see the twist pattern caused by stress.

Putting a polarized sunglass lens in front of a light source, another in front of your eye, a sample between and rotating them you will see all sorts of effects - if the sample is something like a clear plastic you can bend, you can see how the stresses change.

In fact, here's a pic of a quick and dirty field polarimeter...

VIP_tC

Ive noticed the same things when I wear my polarized oakleys in the tC too... ^^^ nice maglight lol.