An Oxford University professor explained how the UK's entry into self-drive cars uses a more affordable system of lasers and camera.
Professor Paul Newman said: "When the car is driving, it is using a small, quite cheap laser on the front of the car that casts a curtain of laser light vertically around.
"As the car moves, it paints the world with this invisible laser light and produces a local idea of what the world looks like in 3D."
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