You’d assume it would be all hands on deck at Tesla with researchers, engineers, and software developers all working together to rectify the car maker’s problematic Autopilot feature, but instead, the company is devoting resources to other futuristic features: like laser windshield wipers.
We’ll be the first to admit that the current method of cleaning a vehicle’s windshield while driving is far from perfect. Assuming the wiper blades themselves aren’t covered in grime and you didn’t forget to refill the wiper fluid, they tend to smear dirt and other debris across the windshield instead of effectively wiping it away. Windshield wipers might do a passable job at preventing raindrops from occluding a driver’s view of the road ahead, but they’re a technology that’s definitely due for an upgrade, and if Tesla has anything to say about it, one day they might be replaced by lasers.
As vehicles become smarter and more reliant on technologies like cameras, sensors, and even energy-generating photovoltaic panels whose performance is hindered by a build-up of dirt, there’s even more demand for a way to keep various surfaces of a vehicle clean that doesn’t involve a daily trip through a car wash.
Originally filed with the United States Patent and Trademark Office on May 10, 2019, but finally approved earlier this week, Tesla’s patent for a “Pulsed Laser Cleaning of Debris Accumulated on Glass Articles in Vehicles and Photovoltaic Assemblies” sounds as foreboding as it does innovative. The patent describes a system where “debris detection circuitry” can determine if dirt has built up on glass surfaces that need to be kept as clean as possible for optimal functionality, like cameras monitoring the road, or even the windshield that a driver is looking through. Based on how much dirt is detected and where it’s located, a laser’s intensity and focus are calibrated to direct the beam specifically to the problem area (imagine a patch of bird poop on your windshield) so that as it’s quickly pulsed it has enough intensity to burn the dirt away, without actually penetrating the glass surface and causing harm to occupants inside, or sensitive electronics.
On one hand, the approach eliminates complicated mechanical machinery that’s prone to failure as well as an additional electric motor putting a heavy strain on an EV’s battery. It also removes the wiper blades moving back and forth across the windshield which can often be a distraction for a driver. On the other hand, a laser powerful enough to burn dirt off a window is definitely something to be concerned about. You’re not even supposed to look directly at the low-power laser diodes used in laser pointers, but the beam’s intensity would have to be increased dramatically for this application.
The patent does describe an approach where the laser’s beam is quickly pulsed so that it “limits penetration of the laser beam to a depth that is less than a thickness of the glass article” and while that might provide some peace of mind for the vehicle’s occupants, what about others around the vehicle, including other drivers on the road, who might be exposed to unwanted reflections of the beam? In an ideal world that would never happen, but in an ideal world self-driven Teslas also wouldn’t crash into police cruisers. The self-cleaning laser system could be limited to use only when the vehicle is safely stopped, or inside a garage even, but then it would be useless for the random times that something splatters across your windshield while you’re on the road. As futuristic as the idea sounds, we’re quite happy to stick with our old-school solution for the time being.