It's late, pitch dark, and a self-driving car winds down a narrow country road.
Suddenly, three hazards appear at the same time.
What happens next?
Before it can navigate this onslaught of obstacles, the car has to detect them— gleaning enough information about their size, shape, and position, so that its control algorithms can plot the safest course.
With no human at the wheel, the car needs smart eyes, sensors that'll resolve these details— no matter the environment, weather, or how dark it is— all in a split-second.
That's a tall order, but there's a solution that partners two things: a special kind of laser-based probe called LIDAR, and a miniature version of the communications technology that keeps the internet humming, called integrated photonics.
To understand LIDAR, it helps to start with a related technology— radar.
In aviation, radar antennas launch pulses of radio or microwaves at planes to learn their locations by timing how long the beams take to bounce back.
That's a limited way of seeing, though, because the large beam-size can't visualize fine details.
In contrast, a self-driving car's LIDAR system, which stands for Light Detection and Ranging, uses a narrow invisible infrared laser.
