Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Tesla Cybertruck Uses Lasers instead of Windshield Wipers!

camalaio

Active Member
May 28, 2019
1,483
2,181
Vernon, BC, Canada
Relevant xkcd (technically "What If?" from the same guy).

EDIT: Ok I actually watched some of the video. Dude is not aware that more and more concept cars have no mirrors (including the rearview mirror) yet the production cars do. I think the Motortrend articles Elon linked to after the unveiling also heavily implied or directly said they Cybertruck was indeed rushed together on very short notice prior to the unveiling (the truck at the event wasn't even a unibody design as discussed in the event, it was still body-on-frame). This could easily explain the lack of wipers.
 
Last edited:

Cyberax

Member
Supporting Member
Jul 28, 2015
441
320
Seattle, WA
Tesla Cybertruck Uses Lasers instead of Windshield Wipers to vaporize water and debris off the windshield:
A laser capable of rapidly vaporizing water from a windshield in heavy rainfall would be absolutely illegal to use. Such a laser can easily cause blindness simply from stray reflections (Class-4 laser product).
 

boaterva

Supporting Member
Supporting Member
Apr 2, 2016
7,575
3,815
Northern Virginia, USA
It’s still two years out... Many things will change. I keep telling everyone who brings up the windows and every other little thing.... :D

There is/was a patent for the laser ‘wipers’ but again who knows what gets to production when.
 

lillyM3

Member
May 5, 2019
20
48
USA
Cyberax; Cybertruck will use a hydrophobic coating on the windshield to remove water like on airplanes when it is travelling at high speed and when rainfall is heavy. However, at low speed, it will use lasers to zap water off the windshield.

Also, the laser doesn't have to be shot at the windshield from outside the windshield. Since the windshield is flat, you could shoot the laser from within the windshield so that the laser travels inside the windshield like a laser travelling through a fiber optic cable. The laser would spot heat where the water droplets are to vaporize the water droplets. The laser would never leave the glass so that there would be no danger to your eyes.

MichaelP90DL; Yes, I know a crazy guy at my gun club will will definitely mount a 50 caliber gun on the back of his Cybertruck.

camalao; You are correct. However, the Model 3 and Model Y unveilings all had windshield wipers.
 
Last edited:
  • Like
Reactions: outdoors

JBee

Member
Nov 23, 2019
160
122
WA
lol. Cars have used lasers for decades, whats so special about that?
Most cars don't come with them anymore since they got rid of CD players and replaced them with MP3 players instead. :p
 

Cyberax

Member
Supporting Member
Jul 28, 2015
441
320
Seattle, WA
lol. Cars have used lasers for decades, whats so special about that?
Most cars don't come with them anymore since they got rid of CD players and replaced them with MP3 players instead. :p
Vaporizing 1 cubic centimeter of water requires 2200 Joules of energy. If we assume that this much water falls on the windshield every second (a weak rain, don't even think about a really hard rain) then you need a continuous 2.2kW laser.

Such lasers are extremely dangerous. Like, EXTREMELY. They will blind you if you come close, with simple stray reflections.

For comparison, a laser pointer typically outputs around 3mW of power - that's almost a million times less than the shieldsmasher laser.
 

Cyberax

Member
Supporting Member
Jul 28, 2015
441
320
Seattle, WA
Also, the laser doesn't have to be shot at the windshield from outside the windshield. Since the windshield is flat, you could shoot the laser from within the windshield so that the laser travels inside the windshield like a laser travelling through a fiber optic cable. The laser would spot heat where the water droplets are to vaporize the water droplets.
This is not how lasers or waveguides work. Lasers can't "sense the heat" and leave the medium.

Lasers travel in fiber optic because of an effect called "total internal reflection" - the difference in refractive indices on the interface between media is large enough for the light to bounce back. A droplet of water on the glass indeed can change the interface so that it won't be totally reflective. So the laser light will shine through the droplet. But it won't _stay_ there, it'll then be scattered by the droplet in all directions.

And a droplet on the windshield inside the car would work just as well.

So nope, laser windshield vipers are just a stupid idea.
 

MichaelP90DL

Active Member
Apr 19, 2019
1,594
1,635
Lancaster, CA
This is not how lasers or waveguides work. Lasers can't "sense the heat" and leave the medium.

Lasers travel in fiber optic because of an effect called "total internal reflection" - the difference in refractive indices on the interface between media is large enough for the light to bounce back. A droplet of water on the glass indeed can change the interface so that it won't be totally reflective. So the laser light will shine through the droplet. But it won't _stay_ there, it'll then be scattered by the droplet in all directions.

And a droplet on the windshield inside the car would work just as well.

So nope, laser windshield vipers are just a stupid idea.
And, perhaps, so are laser windshield wipers. Although both may be dangerous.
 

Cyber_Dav

Member
Nov 30, 2019
149
172
SoCal
Im buying a cybertruck because it will have a HUD.
You know you can have that in any car, yes? Put some transparent/reflective film inside your windshield and put your phone or tablet on your dash (flat, facing up). Hook the tablet to your OBDll port (usually Bluetooth) and run app of your choice (in HUD mode to handle reverse image). All OBDll info can be shown, plus GPS, etc. Better apps allow customization of display.

I used Torque (lite) in my Yamaha Rhino.
 

Cyberax

Member
Supporting Member
Jul 28, 2015
441
320
Seattle, WA
Tame snakes that have built-in organic AI to seek out raindrops and then zap them with laser-vision eyes. I read about it on the internet, it MUST be true, right? :)
And a bonus feature - Gorgon mode for Sentry (snakes automatically retracted when the car is unlocked). I'm definitely liking this idea more and more!
 
  • Like
Reactions: MichaelP90DL

lillyM3

Member
May 5, 2019
20
48
USA
No, you misunderstand what I said. I'll post another video....

Yes, the glass is coated to create the "refractive index" you described. The laser never touches the water droplet on the windshield because the laser never leaves the interior of the glass windshield. The laser heats up the tiny area where the water droplet sits on the windshield to vaporize it using the laser's energy. The laser energy is at the frequency of resonance of water so the water is efficiently vaporized. The laser is not in the visible spectrum so you cannot see it and it will never leave the interior of the glass. The glass is not really glass but ALON (transparent aluminum ceramic oxide nitride) so it has very low specific heat. Therefore, once the car is stopped, the laser turns off. If you touch it after the car stops, the glass will be cool to the touch due to it's low specific heat.

This is hard to understand using text. I will upload another video.

This is not how lasers or waveguides work. Lasers can't "sense the heat" and leave the medium.

Lasers travel in fiber optic because of an effect called "total internal reflection" - the difference in refractive indices on the interface between media is large enough for the light to bounce back. A droplet of water on the glass indeed can change the interface so that it won't be totally reflective. So the laser light will shine through the droplet. But it won't _stay_ there, it'll then be scattered by the droplet in all directions.

And a droplet on the windshield inside the car would work just as well.

So nope, laser windshield vipers are just a stupid idea.
 

drtimhill

Active Member
Apr 25, 2019
1,995
2,617
Seattle
Yes, the glass is coated to create the "refractive index" you described. The laser never touches the water droplet on the windshield because the laser never leaves the interior of the glass windshield. The laser heats up the tiny area where the water droplet sits on the windshield to vaporize it using the laser's energy. The laser energy is at the frequency of resonance of water so the water is efficiently vaporized. The laser is not in the visible spectrum so you cannot see it and it will never leave the interior of the glass. The glass is not really glass but ALON (transparent aluminum ceramic oxide nitride) so it has very low specific heat. Therefore, once the car is stopped, the laser turns off. If you touch it after the car stops, the glass will be cool to the touch due to it's low specific heat.

Why not just zap the water droplets directly with your laser-vision and cut out the middle man?
 
  • Funny
Reactions: MichaelP90DL

camalaio

Active Member
May 28, 2019
1,483
2,181
Vernon, BC, Canada
No, you misunderstand what I said. I'll post another video....

Yes, the glass is coated to create the "refractive index" you described. The laser never touches the water droplet on the windshield because the laser never leaves the interior of the glass windshield. The laser heats up the tiny area where the water droplet sits on the windshield to vaporize it using the laser's energy. The laser energy is at the frequency of resonance of water so the water is efficiently vaporized. The laser is not in the visible spectrum so you cannot see it and it will never leave the interior of the glass. The glass is not really glass but ALON (transparent aluminum ceramic oxide nitride) so it has very low specific heat. Therefore, once the car is stopped, the laser turns off. If you touch it after the car stops, the glass will be cool to the touch due to it's low specific heat.

This is hard to understand using text. I will upload another video.

Even if what you said is possible:

  1. The snippet of the patent shown demonstrates a laser mounted on the hood aimed at the windshield, not some internal glass mechanism.
  2. You still would have to heat the water enough, which requires a massive amount of energy.
Also, this is just a terrible idea because of water spots. Boiling all that water off the windshield would result in a ton of mineral deposits.
 

Products we're discussing on TMC...

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


SUPPORT TMC
Top