Subscribe free to our newsletters via your
. 24/7 Space News .




TECH SPACE
Self-sweeping laser could dramatically shrink 3-D mapping systems
by Staff Writers
Berkeley CA (SPX) Sep 04, 2015


This self-sweeping laser couples an optical field with the mechanical motion of a high-contrast grating (HCG) mirror. The HCG mirror is supported by mechanical springs connected to layers of semiconductor material. The red layer represents the laser's gain (for light amplification), and the blue layers form the system's second mirror. The force of the light causes the top mirror to vibrate at high speed. The vibration allows the laser to automatically change color as it scans. Image courtesy Weijian Yang. For a larger version of this image please go here.

A new approach that uses light to move mirrors could usher in a new generation of laser technology for a wide range of applications, including remote sensing, self-driving car navigation and 3D biomedical imaging.

A team of University of California, Berkeley, engineers led by Connie Chang-Hasnain, a professor of electrical engineering and computer sciences, used a novel concept to automate the way a light source changes its wavelength as it sweeps the surrounding landscape. They report their findings in the journal Scientific Reports, to be published Thursday, Sept. 3.

The advance could have implications for imaging technology using LIDAR, or light detection and ranging, and OCT, or optical coherence tomography.

"Our paper describes a fast, self-sweeping laser that can dramatically reduce the power consumption, size, weight and cost of LIDAR and OCT devices on the market today," said Chang-Hasnain, chair of the Nanoscale Science and Engineering Graduate Group at UC Berkeley. "The advance could shrink components that now take up the space of a shoebox down to something compact and lightweight enough for smartphones or small UAVs [unmanned aerial vehicles]."

LIDAR works by shining a beam of light at a target and measuring the amount of time it takes to bounce back. Because the speed of light is constant, this system can then be used to calculate distance. Self-driving vehicles and remote sensing technology use LIDAR for navigation and the creation of 3D maps.

OCT applies the same principle of measurement to the scale of millimeters in medical imaging. The technology is used to create cross-sectional images of the retina and help with the early detection of retinal diseases, including age-related macular degeneration.

Moving mirrors with light
In both applications, as the laser moves along, it must continuously change its frequency so that it can calculate the difference between the incoming, reflected light and the outgoing light. To change the frequency, at least one of the two mirrors in the laser cavity must move precisely.

"The mechanisms needed to control the mirrors are a part of what makes current LIDAR and OCT systems bulky, power-hungry, slow and complex," said study lead author Weijian Yang, who did this work as a UC Berkeley Ph.D. student in electrical engineering and computer sciences. "The faster the system must perform - such as in self-driving vehicles that must avoid collisions - the more power it needs."

The novelty of the new design is the integration of the semiconductor laser with the mirror. Each laser can be as small as a few hundred micrometers square, and it can be readily powered by an AA battery.

The coupling of the laser with an ultra-thin, high-contrast grating (HCG) mirror allowed the researchers to harness the physical force of the light to move the mirror. The HCG mirror, consisting of rows of tiny ridges, was developed in Chang-Hasnain's lab and has recently been used to create an artificial, chameleon-like skin. With an average force of just a few nanonewtons, or about one-thousandth the weight of an ant, the light exerts enough energy to cause the mirror to vibrate.

'Like a kid on a swing'
"The light acts like a kid on a swing, and the mirror is the swing itself," said Yang, who is now a postdoctoral researcher in biological sciences at Columbia University. "If the child moves his body properly along the swinging path, he can enjoy this 'free' ride without any external force. This is what is happening in this self-sweeping laser."

In their experiments, the researchers found that this optomechanical interaction of the laser and the mirror can sweep across a wavelength range of more than 23 nanometers in the infrared spectrum without the need for external controls.

"That wavelength range would be sufficient for a system that could resolve 50-micrometer surface profile features, even when the target is tens of meters away," said study co-author Adair Gerke, a Ph.D. student in Chang-Hasnain's group.

Moreover, the period of the sweeping cycle can be as short as a few hundred nanoseconds, enabling several million sweeps per second. This speedy sweeping rate enables 3D image capture for real-time videos and visualization of depth change.

The study authors said the next stage of the research will be to incorporate this new laser design in current LIDAR or OCT systems, and to demonstrate its application in 3D video imaging.


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

.


Related Links
University of California - Berkeley
Space Technology News - Applications and Research






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





TECH SPACE
DNA-guided 3-D printing of human tissue is unveiled
San Francisco CA (SPX) Sep 03, 2015
A UCSF-led team has developed a technique to build tiny models of human tissues, called organoids, more precisely than ever before using a process that turns human cells into a biological equivalent of LEGO bricks. These mini-tissues in a dish can be used to study how particular structural features of tissue affect normal growth or go awry in cancer. They could be used for therapeutic drug scree ... read more


TECH SPACE
China Plans Lunar Rover For Far Side of Moon

Russia Eyes Moon for Hi-Tech Lunar Base

Russia Gets Ready for New Moon Landing

ASU chosen to lead lunar CubeSat mission

TECH SPACE
One small step for man as astronaut controls robot from space

What Happened to Early Mars' Atmosphere

ASU instruments help scientists probe ancient Mars atmosphere

Opportunity brushes a rock and conducts in-situ studies

TECH SPACE
New Life for Old Buddy: Russia Tests Renewed Soyuz-MS Spacecraft

Opportunity found in lack of diversity in US tech sector

Boeing Revamps Production Facility for Starliner Flights

In Virginia, TechShop lets 'makers' tinker, innovate

TECH SPACE
Progress for Tiangong 2

China rocket parts hit villager's home: police, media

China's "sky eyes" help protect world heritage Angkor Wat

China's space exploration potential has US chasing its own tail

TECH SPACE
Soyuz rocket with three astronauts launches towards ISS

Slam dunk for Andreas in space controlling rover on ground

Russian ISS Crew's Next Spacewalk Planned for February 2016

Mogensen begins busy ISS tour

TECH SPACE
US Launches Atlas V Rocket With Navy Communications Satellite After Delay

US Navy to Launch Folding-Fin Ground Attack Rocket on Scientific Mission

FCube facility enters operations with fueling of Soyuz Fregat upper stage

SpaceX delays next launch after blast

TECH SPACE
Earth observations show how nitrogen may be detected on exoplanets, aiding search for life

Distant planet's interior chemistry may differ from our own

Earth's mineralogy unique in the cosmos

A new model of gas giant planet formation

TECH SPACE
Self-sweeping laser could dramatically shrink 3-D mapping systems

Using ultrathin sheets to discover new class of wrapped shapes

Customizing 3-D printing

DNA-guided 3-D printing of human tissue is unveiled




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.