-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Double vision (ghosting) at night through windshield?
- Thread starter rmiggins
- Start date
jeturney: regarding your new X 90D, do you notice any ghosting of distant lights (tail lights, head lights, street lights) at night? Thanks.
Tesla replaced my windshield as a goodwill gesture 10 days ago. The double /triple vision and ghosting effects did not vanish, what was noticeable was the fact that I didn't experience distraction/ headaches/ daytime glare and night time magnified scattering of the light that I had to deal with while driving the car. Also the break lights of other cars at night are not as disturbing as it used to be. Other than my personal experience, I couldn't find any tangable characteristic difference between the two windshields until an accidental discovery recently. With the original windshield the effect was at all angles and distances from the dashboard. One could put one's head on the dash and the problem persisted. With the new windshield, it stops at a foot or so above the dashboard (tint level). No ghosting of any kind occurs at that level. The new windshield is a HUGE improvement compared to the original one, it just takes a bit of getting used. I drove it last night on a two lane windy road with no problem at all. I now understand why some owners won't notice it. Again, the 'ghosting" effect is not gone, but there is very little distraction. I get why it is what others call the new "normal" and I am Ok with it.
It's worse than that, it's physics, Jim!!
I am getting the double vision during the day too, with red lights, even in bright sunlight. Makes perfect sense what is going on, it is due to the curvature of the windshield. It is more obvious with the red light, since this region has a longer wavelength. To eliminate this, there would need to be optical coatings applied during the windshield manufacturing process, which of course would make the glass more expensive. I can live with it, just as I lived with the distortions in both front and back glass with my Model S for the past three years. Oh, and the rear glass distortions are still there. It is the price we pay for cutting edge technology. Same as the misalignments in the panels, occasional hiccups with the door actuators etc etc.
I am getting the double vision during the day too, with red lights, even in bright sunlight. Makes perfect sense what is going on, it is due to the curvature of the windshield. It is more obvious with the red light, since this region has a longer wavelength. To eliminate this, there would need to be optical coatings applied during the windshield manufacturing process, which of course would make the glass more expensive. I can live with it, just as I lived with the distortions in both front and back glass with my Model S for the past three years. Oh, and the rear glass distortions are still there. It is the price we pay for cutting edge technology. Same as the misalignments in the panels, occasional hiccups with the door actuators etc etc.
aija SigX 649
Winged Lion
Still waiting on findings from Tesla's investigation on this issue and subsequent corrective actions. IMO Ghosting is unacceptable and must/will be addressed at any cost.
Last edited:
retinaguy
Member
Blue has the longer wavelength compared with red and blue causes more aberrations due to being refracted more by surfaces that refract light.
Blues are somewhere around 450-500nm, but reds are around 650-700nm. Red wavelengths are longer.
retinaguy
Member
Yes you are right. I goofed. Typed quicker than I was thinking. But blue is refracted more and causes more aberrations. That's the rationale behind "blue blocker" glasses.
I think one thing to keep in mind is this:
Not to generalize, but most folks able to afford Model S and Model X are older, and may not have as good eyesight, where those working at Tesla may be younger and have better eyesight
But seriously, I have sat in a few Model X's, and I probably encountered what is being spoken of exactly once, and I couldn't reproduce the issue. It's not a Tesla problem as people have stated, it is physics. Tesla doesn't make the windscreen glass. Also, the upper, tinted portion is more curved than the bottom portion that people actually look through to drive, so I don't think double vision through the upper portion is that much of a safety risk as people are making it out to be.
Not to generalize, but most folks able to afford Model S and Model X are older, and may not have as good eyesight, where those working at Tesla may be younger and have better eyesight
But seriously, I have sat in a few Model X's, and I probably encountered what is being spoken of exactly once, and I couldn't reproduce the issue. It's not a Tesla problem as people have stated, it is physics. Tesla doesn't make the windscreen glass. Also, the upper, tinted portion is more curved than the bottom portion that people actually look through to drive, so I don't think double vision through the upper portion is that much of a safety risk as people are making it out to be.
Another thought: Since it appears that the magnitude of the problem differs from windshield to windshield (see report about how a replacement windshield had much improved behavior), perhaps it is the Model X's unique windshield with the portion tinted. How is that tinting of the upper portion accomplished? If they do any kind of deposition (coating) of metals or something as part of the tinting process, perhaps there's some "overspray" on some windshields more than others. Such overspray could increase the reflectivity and make the multiple reflections worse. Just a thought.
It's my guess that these are very large and difficult windscreens to make. I suspect that part of the process is to laminate multiple layers together. If the lamination process is not done properly, you can have issues like:
- small air gaps in between the layers
- uneven pressure on layers causing compression stresses rippling through the layer
Even if the windscreen is perfect during manufacturing, undo stresses during transport can also warp the windscreen and induce this issue, especially if all the layers haven't cured 100% yet.
If that is the case, these irregularities can induce ghosting to varying degrees, depending on the magnitude of these imperfections. Therefore, some will not have this issues and some will, to varying degrees. This is an issue that Tesla needs to bring up with their supplier (in Peru, I believe). It would be helpful if Tesla built a test harness to validate the windscreen prior to leaving the factory. It could be as simple as shining a laser through the windscreen and monitoring the laser image on the driver's seat.
- small air gaps in between the layers
- uneven pressure on layers causing compression stresses rippling through the layer
Even if the windscreen is perfect during manufacturing, undo stresses during transport can also warp the windscreen and induce this issue, especially if all the layers haven't cured 100% yet.
If that is the case, these irregularities can induce ghosting to varying degrees, depending on the magnitude of these imperfections. Therefore, some will not have this issues and some will, to varying degrees. This is an issue that Tesla needs to bring up with their supplier (in Peru, I believe). It would be helpful if Tesla built a test harness to validate the windscreen prior to leaving the factory. It could be as simple as shining a laser through the windscreen and monitoring the laser image on the driver's seat.
Everything's lasers these days.
I think they could QC them at the Peruvian factory by doing something similar. It could be pretty easily automated if they employed a device that measured the distance between the ghost dots from the laser, and could reject outside of a certain tolerance.
Similar threads
