Researchers at Purdue University
and Stanford University believe they have found a
novel laser light sensing technology that is more robust and less expensive
than currently available with a wide range of uses, including a way to guide
fully autonomous vehicles.
The researchers say their
innovation is orders of magnitude faster than conventional leading-edge laserbeam steering devices that use phased antenna-array technology. The laser beam steering
being tested and used by Purdue and Stanford is based on light-matter
interaction between a silicon-based metasurface and short light pulses produced
for example by a mode-locked laser with a frequency-comb spectrum. Such a
beam-steering device can scan a large angle of view in nanoseconds orpicoseconds compared with the microseconds current technology takes.
"This technology is far less
complex and uses less power than existing technologies," said Amr
Shaltout, a post-doctoral research fellow in Materials Science and Engineering
at Stanford who conceived the idea for the method.
"The technology merges two
different fields of nanophotonic metasurfaces and ultrafast optics."
Laser beam steering is a vital
technology that can be used in a wide variety of areas including navigation,
space flights, radar applications, imaging, tag-scanners, robotics,
archaeology, mapping and atmospheric physics. Faster laser scanning is directly
related to higher frame rates as well as improved imaging resolution.
Shaltout came up with the concept
while earning his Ph.D. from the Vladimir Shalaev research group at Purdue's School of Electrical and Computer Engineering and
delineated it at Stanford when working with the research group of Mark
Brongersma.
"The idea proposed by Amr is so
powerful that we were honestly surprised that nobody did it before because it
is so simple, so efficient, much easier than what people used so far and works
much faster," said Shalaev, the Bob and Anne Burnett Distinguished
Professor of Electrical and Computer Engineering at Purdue. This as a wonderful
example of fruitful collaboration between Purdue and Stanford."
The researchers say their
innovation is chip-compatible technology that doesn't require additional
sources of energy. It is based on light-matter
interaction between metasurfaces and short pulses from mode-locked
lasers with equally spaced phased-lock frequency lines. Another key element is
using a metasurface based on patterned silicon film.
"That's the basis for
all of the electronic circuitry at the nanoscale to give this exciting
functionality that allows the beam steering to happen," said Brongersma, a
professor in Stanford's Department of Materials Science and Engineering.
Autonomous cars depend on
light detection and ranging, or lidar, which is similar to radar only instead
emits infrared or visible light that measures how long it takes for the pulses
to reflect back off objects and take their images. It would replace the
spinning device frequently seen atop roofs of autonomous cars. But that
existing technology remains expensive as businesses look for ways to transform
the burgeoning autonomous car industry.
Shaltout said the use of photonic
metasurfaces was key to the new advancement. He said metasurfaces provide
simple, compact and power efficient solutions to photonics design. The
combination of those two technologies provide a much simpler approach.
In current phased-array opticaltechnology, each antenna needs to be controlled in what it radiates
individually. Under Shaltout's system, each of the structures emit slightly
different frequencies, meaning there is no need to address each individual
antenna continuously and consuming power during that process.
Shaltout said an interdisciplinary
solution was the key factor.
"Sometimes working outside our
field help us to see, to find solutions to problems in different fields and
just link them together," he said.
The challenge for the researchers now
is to scale up the innovation and move it from the laboratory to the real
world. They are looking for investors, partners or possibly licensing
agreements as they work to move forward scaling up the technology. The first
developments might be in areas such as scanning devices at stores, airports or
in many other areas before moving on to autonomous
cars and automobile original equipment manufacturers.
"This seems to be a disruptive
solution which could make a big difference in this huge, emerging
industry," Shalaev said.
No comments:
Post a Comment