Double vision (ghosting) at night through windshield?

[Mark Z]

...What bothered me during the test drive, hopefully more than this ghosting issue may....is the reflection of the speaker grate onto the interior of the windshield. It was enough to distract me. Hopefully I can tune that out, lol.

Anyone else find this annoying??

Absolutely not. The grate or grill is so much better than the reflections of plastic air vents in the production Model S.

In addition to Model X, I was fortunate to purchase a 2012 Model S Signature with the same speaker grill instead of the exposed air vents. Every time I got into a Model S loaner, the plastic air vent reflections were very disturbing. I am very happy with the speaker grill next to the windshield.

 

[dwebb66]

I was worried coating the windshield, particularly with a thicker film (i.e. tint) or coating could make the "problem" worse. I mean, it's introducing another gradient for light to reflect/refract through, right? I'd love to hear if someone could post pics of this who has a tinted windshield... please?

I'm not sure a single picture I'll help, you would need to have a picture from that windshield prior to tinting and one after in similar conditions. I state this because some people are not seeing the issue (very much) and others are seeing it a lot. One photo of a 'random' windshield with tint will not add any meaningful data to the analysis of the issue.

 

[ddddd]

I am going to say that the new windshield is actually significantly improved over the prior one now. Its still not clear compared to any other car i drive or have driven. Agree with ElGuapo and others, that its not what you expect when you pay this amount for a new car. going to wait and see if Tesla figures this out on their own and periodically ask different SC's what their service response is in 3/6/12 month intervals.

But again, for now, at least it is much better than before.

re happiness guarantee - i thought it was for lease only too, but then my delivery rep in Fremont said this week i could use it to trade in if i wanted. so a little confusion there.

"i could use it to trade in if i wanted": Would you mind clarifying what this means? Sorry if I'm a bit dense; thanks.

 

[Mark Z]

...the reflection of the speaker grate onto the interior of the windshield. It was enough to distract me...

Here is a link to a recent photo someone posted that shows their plastic windshield defog vents that are much more distracting than the Model X windshield grill: http://i.imgur.com/jNUb10c.jpg

Above photo from post: Supercharger - Santa Ana (permit found)

 

[ddddd]

I just received my X 90D on Wednesday - I'll look for this.

Any feedback on the ghosting? Thanks.

 

[mfel]

An interesting thoughts occurred to me just now.

Using only first order physics based off refraction (simple lens kind of stuff), the reflection "direction" (above or below) is purely determined by the angle of windshield. As demonstrated in that diagram, it will only be above original for normal windshield viewing. It can't go both directions. And it should not matter how many or the type of layers that make up the windshield. Well, so long as all those materials are normal solid kind of stuff with index of refraction > 1.0.

However, in thinking a bit more about a similar effect in the autodimming rear view mirrors. I see very strong ghosting in both directions up and down in both my cars with autodimming. I believe, but haven't confirmed, that those use some kind of variable defraction grating (maybe with LCD?) to control the amount of reflected light. A diffraction grating, lots of little lines very close together cause an interference effect that can cause multiple order images symmetrically, in both directions perpendicular to the direction of the lines. But the lines need to be on the order of a wavelength of light for it to work effectively. I could totally wrong on how autodimming rear view mirrors work and am too lazy to research them right now. .

Anyways, that led me to wonder if during manufacturing there could be any horizontal lines be induced in the windshield that could cause similar effect in addition to the internal reflection. Perhaps something like when they bend the glass that some internal ripples of higher/lower density are created. Not too likely I think to cause strong effect, but perhaps that could explain some only some people see ghosting below but pretty much everyone sees the reflection effect ghosting above the original.

Lastly, did anyone try my simple experiement? Take a laser pointer and shine it through the front windshield and observe the dots inside the car. Shine on a card or something. I would think it should clearly demonstrate the ghosting, provided the dot is smaller than the thickness of the windshield. Perhaps not individual dots, but at least a smeared tail on top side.

 

[mfel]

Well, turns out I was wrong about autodimming rear view mirrors. They use electrochromic gels for dimming, not specifically diffraction effect. However I do know I see many ghosts above and below at night in the rear view mirror. Not sure what that's about.

 

[aesculus]

Showed the ghosting to my wife last night. She said no big deal and did not understand why there was a concern from everyone. Note our car has some ghosting with a secondary image slightly above the primary. It only shows up on moderately distant objects. For objects that are nearby or in the immediate viewing area we have no ghosting. But both of us seem to be able to ignore it and it does not bother us at all.YMMV.

 

[ohmman]

YMMV.

YGMV.

 

[eleXtrons]

While my X is in the SC I was given a brand-new loaner Model S. This new S windshield also has ghosting, but it is considerably less pronounced/distracting than in my X. Unlike the X that has one main ghost image above the real image, the ghosting in the S causes one ghost image above and one ghost image below the real image both ghost images are of equal strength, very much like one sees in the video of the 2012 Prius on page 10 of this thread (posted by @DuplexDianne). I almost wonder if part of the reason the ghosting is more distracting in the X is because of this asymmetry (ie only above) and/or because in the X the light from the bottom and top ghosts combine into a single, stronger, combined top ghost image. What I am saying is that maybe the layering is different in the X such that instead of the reflected light being split forming two medium strength ghosts, in the X the same amount of light is reflected, but they combine into a single, stronger ghost image above the real image.

Confusing things is that on the model X there are actually often two ghost images above the real image, but the top most ghost image is the faintest. I think this second/top ghost is just a 'ghost' of the first ghost image (which is very bright).

@mfel: I have also noticed many multiple images in the rearview mirror, but I think they may be caused by reflections off the horizontal defrost wires in the rear window. (just a hunch, I have not confirmed).

Note, as pointed out before, gentle waviness in glass causes a 'fun-house' style distortion (that can be a real problem with cheap aftermarket windshields) but that style of defect will have no influence on this ghosting problem.

...Still looking for a single, confirmable, example of an X windshield that does not have this ghosting problem.

 

[lloyds]

Received my car back from SC and they are aware of the issue, but do not yet have a "fix". They will contact me as soon as they do.

 

[DuplexDianne]

Here is a link to a recent photo someone posted that shows their plastic windshield defog vents that are much more distracting than the Model X windshield grill: http://i.imgur.com/jNUb10c.jpg

Above photo from post: Supercharger - Santa Ana (permit found)

The grate's reflection seemingly disappears when I put my polarized sunglasses on, so at least that problem is solved. I wonder if it will do the same for the ghosting...

 

[systemcrashed]

The grate's reflection seemingly disappears when I put my polarized sunglasses on, so at least that problem is solved. I wonder if it will do the same for the ghosting...

A certain song comes to mind...

 

[TylerCA]

This artifact on the windshield is quite annoying for myself during night drives. Im not great at photos, but i liken it to a camera out of focus. I try not to stare at traffic lights at night

 

[cuse44]

The grate's reflection seemingly disappears when I put my polarized sunglasses on, so at least that problem is solved. I wonder if it will do the same for the ghosting...

This worked for me. I posted in the delivery thread about this. Here are the two photos I used to try and capture this.

One normal - where you can see the ghosting on the car headlights and above red light.

And this one taken with my polarized sunglasses between the iphone camera and the windshield. While blurry, you will notice no ghosting in the photo.

 

[DuplexDianne]

So that seems like an easy fix...wearing polarized sunglasses while driving at night if the ghosting (if any) bothers the driver/passenger. I've never worn my sunglasses at night before. I'll give it a try!

 

[vandacca]

So that seems like an easy fix...wearing polarized sunglasses while driving at night if the ghosting (if any) bothers the driver/passenger. I've never worn my sunglasses at night before. I'll give it a try!

This is recommended by Corey Hart.

 

[aesculus]

So could Tesla apply a polarized film then to correct it?

 

[MickC]

I'm having the same effect in a Mercedes S class coupe during the day when looking at led breaking lights.. so not only a Tesla problem.

 

[flar]

So could Tesla apply a polarized film then to correct it?

It's an interesting thought, but a polarizing filter would reduce the total light that makes it through, in addition to eliminating nearly all of the bounced light. It would effectively be "tinting" the windshield which isn't exactly safe and illegal in many/most states.

Another idea would be to use the same materials used in LCDs to twist the light. The reflection being seen had to bounce off of 2 different surfaces, each time the light oriented parallel to the surface was bounced. Both the leading and trailing slopes of the glass are parallel which means once the light bounces from one surface, it is correctly oriented to bounce fairly efficiently off of the other surface and back into your eyes. If a liquid crystal rotated the light bouncing off of the first surface then it would less efficiently bounce off of the second surface and very little of the bounced light would reach your eyes. But, nearly all of the light that went through in the first pass would reach your eyes. I don't believe any power would be needed as the liquid crystals will twist light even in their natural resting state, but if someone is a display engineer, feel free to correct me on that...