‘Whispering gallery mode resonators’ recorded real-time temperature data and, mounted on a drone, mapped temperature distribution
A team of researchers at Washington University in St. Louis is the first to successfully record environmental data using a wireless photonic sensor resonator with a whispering-gallery-mode (WGM) architecture.
The photonic sensors recorded data during the spring of 2017 under two scenarios: one was a real-time measurement of air temperature over 12 hours, and the other was an aerial mapping of temperature distribution with a sensor mounted on a drone in a St. Louis city park. Both measurements were accompanied by a commercial thermometer with a Bluetooth connection for comparison purposes. The data from the two compared very favorably.
In the grand world of the “internet of things” (IoT), there are vast numbers of spatially distributed wireless sensors predominately based on electronics. These devices often are hampered by electromagnetic interference, such as disturbed audio or visual signals caused by a low-flying airplane and a kitchen grinder causing unwanted noise on a radio.
But optical sensors are “immune to electromagnetical interference and can provide a significant advantage in harsh environments,” said Lan Yang, the Edwin H. & Florence G. Skinner Professor of Electrical & Systems Engineering in the School of Engineering & Applied Science, who led the study from which the findings were published online Sept. 12 in Light: Science and Applications.
“Optical sensors based on resonators show small footprints, extreme sensitivity and a number of functionalities, all of which lend capability and flexibility to wireless sensors,” Yang said. “Our work could pave the way to large-scale application of WGM sensors throughout the internet.”
Yang’s sensor belongs to a category called whispering gallery mode resonators, so named because they work like the famous whispering gallery in St. Paul’s Cathedral in London, where someone on the one side of the dome can hear a message spoken to the wall by someone on the other side. Unlike the dome, which has resonances or sweet spots in the audible range, the sensor resonates at light frequencies and also at vibrational or mechanical frequencies, as Yang and her collaborators recently showed.
“In contrast to existing table-sized lab equipment, the mainboard of the WGM sensor is a mere 127 millimeters by 67 millimeters — roughly 5 inches by 2.5 inches — and integrates the entire architecture of the sensor system,” said Xiangyi Xu, the paper’s first author and a graduate student in Yang’s lab.
“The sensor itself is made of glass and is the size of just one human hair; it is connected to the mainboard by a single optical fiber,” Xu said. “A laser light is used to probe a WGM sensor. Light coupled out of the sensor is sent to a photodetector with a transmission amplifier. A processor controls peripherals such as the laser current drive, monitoring circuit, thermo-electric cooler and Wi-Fi unit.
In her WGM, light propagates along the circular rim of a structure by constant internal reflection. Inside the circular rim, light rotates 1 million times. Over that space, light waves detect environmental changes, such as temperature and humidity, for example. The sensor node is monitored by a customized operating systems app that controls the remote system and collects and analyzes sensing signals.
Wireless sensors, whether electronic or photonic (light-based), can monitor such environmental factors as humidity, temperature and air pressure. Applications for wireless sensors encompass environmental and health-care monitoring, precision agricultural practices and smart cities’ data-gathering, among other possibilities. Smart cities are connected cities driven by internet data-harvesting. Precision agriculture uses digitized geographic information systems for precision agricultural practices such as soil mapping, which enables precise fertilizer and chemical applications and choice of seed selection for more efficient and profitable farming.
Yang and her colleagues had to address stability issues, which were handled by the customized operation systems app they developed, and miniaturization of bulky laboratory measurement systems.
“We developed a smartphone app to control the sensing system over WiFi,” Yang said. “By connecting the sensor system to the internet, we can realize real-time remote control of the system.”
In June 2017, Yang and her group mounted the whole system on the outside wall of a building and accumulated a plot of the frequency shift of the resonance. They compared their data with the commercial thermometer.
“Thanks to their small size, the capability and flexibility of wireless photonic sensors can be improved by making them mobile,” Yang said.
The researchers also mounted their system on an unmanned drone in May 2017 alongside the commercial thermometer. When the drone flew from one measurement location to others, the resonance frequency of the WGM shifted in response to temperature variations.
“The measurements matched well with results from the commercial thermometer,” she said. “The successful demonstrations show the potential applications of our wireless WGM sensor in the IoT. There are numerous promising sensing applications possible with WGM technology, including magnetic, acoustic, environmental and medical sensing.”
The miniaturization of resonator sensing systems represents an exciting opportunity for IoT, as it will enable IoT to exploit a new class of photonic sensors with unprecedented sensitivity and capabilities,” said Chenyang Lu, the Fullgraf Professor in the Department of Computer Science & Engineering and a co-author of the paper.
The Latest on: Photonic sensor
via Google News
The Latest on: Photonic sensor
- Biochemical Sensors Market Value to grow at a global CAGR of 3.5% during 2019-2025on September 6, 2019 at 7:26 am
This groundbreaking innovation will encourage various end-use manufacturers to use this, resulting in the growth of the biochemical sensors market. Photonic Crystal Cavity Devices to Stimulate ...
- Photonic Science is pleased to announce its 16 megapixel sCMOS cameraon September 5, 2019 at 3:59 pm
Photonic Science is pleased to announce its 16 megapixel sCMOS ... For deep UV applications the camera can be supplied with a back-illuminated sensor.
- Optical Filters For LiDAR Laser Sensors Brochureon September 5, 2019 at 1:19 pm
Iridian Spectral Technologies offers LiDAR laser sensor systems with common laser wavelengths including 532 nm, 905 nm, 1064 nm, and 1550 nm. These filters provide more signal with less background and ...
- ORCA-Fusion Digital CMOS Camera — C14440-20UPon September 4, 2019 at 2:45 pm
Hamamatsu Photonics’ ORCA-Fusion C14440-20UP has been developed from the sensor up. It balances the intricate nuances of camera features to deliver striking images and strong data at all lights levels ...
- AMS takes its Osram acquisition to shareholderson September 4, 2019 at 2:32 pm
AMS subsequently bid higher on Aug. 12, when it also said it would dump Osram’s IoT lighting business, which ams described as “non-core” to its mission of creating a “global leader in sensor solutions ...
- InGaAs Linear Image Sensor—G13913-256FGon September 4, 2019 at 12:11 am
Let us help you with your inquiries, brochures and pricing requirements Request A Quote Download PDF Copy Download Brochure The near-infrared linear image sensors, offered by Hamamatsu Photonics, are ...
- Austria's AMS makes $4.8 B counterbid for Germany's Osramon September 3, 2019 at 10:04 am
is interested in Osram's technologies for self-driving cars and wants to create a global power in sensors and photonics. Osram shareholders who have already decided to tender for the private equity ...
- Photonic Sensors Market Seeking Excellent Growth | Honeywell International, Samsung, Toshiba, Mitsubishi Electric, Fujifilmon September 3, 2019 at 4:22 am
Sep 03, 2019 (HTF Market Intelligence via COMTEX) -- Global Photonic Sensors Market Report 2019 is latest research study released by HTF MI evaluating the market, highlighting opportunities, risk side ...
- University of Strathclyde to host new quantum research centeron September 2, 2019 at 2:55 pm
Photonics and quantum technology development firm M Squared ... technologies that take advantage of the behaviour of atomic-scale physics, including quantum sensors for measuring gravity and ...
via Bing News