I believe that LIDAR will be to silicon photonics what the accelerometer was to MEMS.
The real challenge that the article only touched upon is to get lasers into the same package and keep the costs down. This is still an active area of pursuit in both research and industry--though, there are several promising methods emerging. The $10 cost used in the article is likely closer to the cost of the bare silicon die. Packaging is always the expensive part of optics (doubly so if the lasers are not monolithically or heterogeneously integrated onto the same die). That being said, even with today's technology, integrating a laser chip and a silicon photonics chip into a package is easily south of $1k, which is what they quoted competing technologies costing.
I look forward to seeing these sensors integrated into my self-driving car in 5-10 years.
From this part of the article, the team seems fairly confident in their ability to integrate the laser onto the same die as the waveguides. This seems very plausible to me, given how standard this integration is in communications applications (eg fiber optic transceivers)
> Our device is a 0.5 mm x 6 mm silicon photonic chip with steerable transmitting and receiving phased arrays and on-chip germanium photodetectors. The laser itself is not part of these particular chips, but our group and others have demonstrated on-chip lasers that can be integrated in the future.
The Watts group at MIT has done some fantastic work into rare-earth doped silicon waveguides to produce lasers on a silicon platform [0]. However, I believe this work is still very much in the research stage. I'm not convinced their method is scalable to production for this $10 & million-unit-per-year LIDAR application since Erbium-doped waveguide lasers still require an off-chip pump laser source.
Even at 2 meter range with centimeter resolution, these devices would be a much better solution to the "local obstacle" problem than ultrasonics today. Mobile platforms moving around in spaces with a lot of miscellaneous obstacles have to either be compliant (or padded) enough to just push through them or slow enough to detect them and move around them.
The real challenge that the article only touched upon is to get lasers into the same package and keep the costs down. This is still an active area of pursuit in both research and industry--though, there are several promising methods emerging. The $10 cost used in the article is likely closer to the cost of the bare silicon die. Packaging is always the expensive part of optics (doubly so if the lasers are not monolithically or heterogeneously integrated onto the same die). That being said, even with today's technology, integrating a laser chip and a silicon photonics chip into a package is easily south of $1k, which is what they quoted competing technologies costing.
I look forward to seeing these sensors integrated into my self-driving car in 5-10 years.