Polarized glasses are great. Why not make vehicles with polarized windshields? Follow up, why not also make them with ceramics for better heat reflection?
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You don’t always want a tinted windshield because sometimes it is dark. You know, like at night. So polarizing a clear windshield doesn’t make much sense.
Plus, many sunglasses are polarized because as you said polarized glasses are great. But there is no standard to what orientation the polarization is, and if you try to look through two polarized filters that aren’t aligned then all the light gets blocked. It wouldn’t be good to put on your sunglasses and your windshield becomes opaque to your view!
There are also more minor issues like if someone else wearing polarized glasses looks at a car and their windshield is apparently opaque, blocking what might otherwise be useful or even critical view of and communication with the other driver. Like you can’t see if they are looking at you, waving at you, and they *think* you *can* see them, etc.
Some car windshields are polarized. Take your glasses and turn them 90 degrees and either lighter or darker.
It’s a first world problem but I can’t see the heads up display in my car when wearing polarized sunglasses. I have to keep a pair in the car to drive with or tilt my head at 45 degrees
That’s pretty much what tint films are but in many places it’s illegal to tint the windshield. Also pretty dangerous at night and low visibility conditions.
OP when their ceramic windshield breaks and a huge shrapnel gets stuck in their chest: “Worth it for the heat reflection.”
The windshields on vehicles aren’t made from just any old glass, they are specil tempered glass that is more resistant to breaking and when it does break, it turns into many tiny granules, instead of big chunks of glass. This reduces the chance of major injury. Now, I’m not entirely sure you can’t do this with ceramic, but I don’t think so.
You don’t really want polarized glass in your car, as it can actually reduce visibility of some features on the road, such as ice or water. It also reduces the amount of light that is let in, reducing visibility at night.
Plus it doesn’t really make sense to do this to an entire windshield when you can just put on the polarized glasses. That way, you can always take them off when you need more light.
The windshield serves a very simple, crucial purpose in the design of an automobile: it provides the driver with a way to clearly see the road without getting a face full of wind and bugs. Windshields also break. It’s pretty much a given if you drive regularly that you’re going to have to replace a windshield sooner or later.
When you do, do you want to pay for the safety-laminated standard, or do you want to pay for the polarized ceramic version at a cost of several thousand dollars?
I guarantee your auto insurance company knows which version of windshield they’re willing to pay for, and it’s not the luxury version.
Nope. Polarized glasses alone mess with many flat-panel displays and almost all LCDs. Some of the laminated glass panels actually cause artifacts. Polarized glasses have their place and drivers should have the choice. Pilots in particular have to be very careful with what kind of sunglasses they use; the FAA straight up says that polarized lenses are not recommended.
Think of the failure mode. If someone wears polarized glasses on an already polarized windshield, it will likely become fully opaque at certain angles, eliminating forward visibility. This is a bad thing. Warning labels like “non-polarized glasses only” aren’t going to solve that, just hopefully let the manufacturer say “there was a warning label” when they get sued.
I’m not sure which ceramics you mean. But there are aftermarket treatments.
If you’re asking why they’re not standard or options it comes down to the fact that it’s not worth it for the vehicle manufacturer to build that into its entire product line for the whole market when aftermarket add-ons are available. Some high-end cars do spend extra on IR rejecting glass. Note, high end and spend extra.
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