Public service announcement: don't point your phone camera directly at a lidar sensor.

A video recently shared on Reddit demonstrates why. As the camera zooms in on the sensor affixed to the top of a Volvo EX90, a whole galaxy of colorful dots is burned into the image, forming over the exact spot that the flashing light inside the lidar device can be seen.

What you're witnessing isn't lens flare or a digital glitch — it's real, physical damage to the camera. And it's permanent.

"Lidar lasers burn your camera," the Reddit user warned. 

Never film the new Ex90 because you will break your cell camera.Lidar lasers burn your camera.
byu/Jeguetelli inVolvo

Lidar is short for light detection and ranging, and it's become the go-to way for automakers to enable their self-driving cars to "see" their surroundings (unless you're Tesla, that is). The sensors work, essentially, by shooting a constant stream of infrared laser beams to measure the distance to nearby objects, which a computer uses to form a 3D reconstruction of everything in the vicinity of the vehicle.

We can't see the laser beams since they're in a wavelength outside the range of human vision. But cameras, on the other hand, are all too sensitive to the powerful beams. Their delicate little sensors can be damaged if they're brought too close to a lidar source, or if a long lens is used to look at one. As The Drive notes in its coverage, this is why backup cameras are usually unaffected, since they use an ultra-wide angle lens. In the video, you'll also notice that the burn-in damage disappears when the camera zooms out: that's the camera transitioning from a long lens to its undamaged short one.

To its credit, Volvo explicitly warns about lidar damage on its support page and its owners manual, but that hasn't stopped a few surprised owners from learning about it the hard way. 

And honestly, we can't really blame them. The phenomenon has even caught a self-driving car engineer off-guard, who discovered that their $2,000 Sony camera's sensor was permanently fried after attending a CES show where lidar-equipped cars were being exhibited.

This is a risk with potentially any car's lidar tech and not just Volvo's, to be clear. After The Drive reached out, the Swedish automaker doubled down on its warning.

"It's generally advised to avoid pointing a camera directly at a lidar sensor," a Volvo representative told The Drive. "The laser light emitted by the lidar can potentially damage the camera's sensor or affect its performance."

"Using filters or protective covers on the camera lens can help reduce the impact of lidar exposure," the Volvo rep added. "Some cameras are designed with built-in protections against high-intensity light sources."

If reading all this has you worried about your eyeballs, fret not: according to experts, the lidar beams used in cars are harmless. Volvo's lidar system, for example, uses 1550-nanometer lasers, and at that wavelength, the light can't even reach the retina.

We still wouldn't recommend staring at them, though.

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The post Something Wild Happens When You Try to Take a Video of a Car's Sensors appeared first on Futurism.

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Something Wild Happens When You Try to Take a Video of a Car's Sensors