Voyant Photonics claims they have a lidar sensor, based on the use of silicon photonics that is so small it can balance on the head of a pin. Now this is where things start to get interesting.
From an article in Tech Crunch by Devin Coldeway.
Lidar is a critical method by which robots and autonomous vehicles sense the world around them, but the lasers and sensors generally take up a considerable amount of space. Not so with Voyant Photonics, which has created a lidar system that you really could conceivably balance on the head of a pin.
Before getting into the science, it’s worth noting why this is important. Lidar is most often used as a way for a car to sense things at a medium distance — far away, radar can outperform it, and up close, ultrasonics and other methods are more compact. But from a few feet to a couple hundred feed out, lidar is very useful.
Unfortunately, even the most compact lidar solutions today are still, roughly, the size of a hand, and the ones ready for use in production vehicles are still larger. A very small lidar unit that could be hidden on every corner of a car, or even inside the cabin, could provide rich positional data about everything in and around the car with little power and no need to disrupt the existing lines and design. (And that’s not getting into the many, many other industries that could use this.)
Lidar began with the idea of, essentially, a single laser being swept across a scene multiple times per second, its reflection carefully measured to track the distances of objects. But mechanically steered lasers are bulky, slow and prone to failure, so newer companies are attempting other techniques, like illuminating the whole scene at once (flash lidar) or steering the beam with complex electronic surfaces (metamaterials) instead.
One discipline that seems primed to join in the fun is silicon photonics, which is essentially the manipulation of light on a chip for various purposes — for instance, to replace electricity in logic gates to provide ultra-fast, low-heat processing. Voyant, however, has pioneered a technique to apply silicon photonics to lidar.
In the past, attempts in chip-based photonics to send out a coherent laser-like beam from a surface of lightguides (elements used to steer light around or emit it) have been limited by a low field of view and power because the light tends to interfere with itself at close quarters.
Voyant’s version of these “optical phased arrays” sidesteps that problem by carefully altering the phase of the light traveling through the chip. The result is a strong beam of non-visible light that can be played over a wide swathe of the environment at high speed with no moving parts at all — yet it emerges from a chip dwarfed by a fingertip.
For the complete article click here.
