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 UC 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, 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.
Read more: Self-sweeping laser could dramatically shrink 3D mapping systems
The Latest on: 3D mapping systems
[google_news title=”” keyword=”3D mapping systems” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: 3D mapping systems
- Digital Mapping Helps First Responders Better Navigate Inside Buildingson May 13, 2024 at 6:13 am
Agencies are using S&T-funded Mappedin to find their way quickly during critical incidents in schools and public buildings.
- Largest-Ever 3D-Mapped Piece Of The Human Brain Could Still Fit On A Grain Of Riceon May 12, 2024 at 5:00 pm
This vivid rainbow of cells represents the largest-ever high-resolution 3D map of a section of the human brain. The largest, yes, but still just a cubic millimeter in size – about half a grain of rice ...
- Biosense Webster unveils new version of CARTO 3 Electro-Anatomical Mapping Systemon May 11, 2024 at 3:42 am
Irvine: Biosense Webster, Inc., a global leader in cardiac arrhythmia treatment and part of Johnson & Johnson MedTech, has announced the launch of CARTO 3 System Version 8, the latest version ...
- Biosense introduces CARTO 3 System Version 8on May 9, 2024 at 6:29 am
Cardiac arrhythmia diagnosis and treatment specialist Biosense has launched CARTO 3 System Version 8, a 3D heart mapping system used in cardiac ablation procedures. This latest version introduces new ...
- Biosense Webster Launches New Version of CARTO™ 3 Electro-Anatomical Mapping Systemon May 8, 2024 at 1:46 pm
Biosense Webster, Inc., a global leader in cardiac arrhythmia treatment and part of Johnson & Johnson MedTech, announces the launch of CARTO™ 3 System Version 8, the latest version of the company's ...
- Biosense Webster launches new AI-powered version of heart mapping techon May 8, 2024 at 6:38 am
Johnson & Johnson MedTech’s Biosense Webster today announced the launch of the latest version of its Carto 3 heart mapping system.
- Indian filmmaker directs gigantic 3D ‘cinematic mapping’on May 7, 2024 at 6:57 am
Indian filmmaker Mani Shankar has directed a series of cinematic projection mapping experiences that are described as a fusion of projection mapping and cinema.
- New ISS initiative aims to revolutionize space 3D mappingon April 27, 2024 at 8:42 am
A new project by the ISS National Laboratory could provide a breakthrough in 3D mapping technology and transform space exploration.
- Airborne single-photon lidar system achieves high-resolution 3D imagingon April 25, 2024 at 7:00 am
Researchers have developed a compact and lightweight single-photon airborne lidar system that can acquire high-resolution 3D images with a low-power laser. This advance could make single-photon lidar ...
- Airborne single-photon lidar system achieves high-resolution 3D imagingon April 24, 2024 at 5:00 pm
3D terrain mapping and object identification. Researchers have developed a compact and lightweight single-photon airborne lidar system that can acquire high-resolution 3D images with a low-power ...
via Bing News