Researchers build ultraprecise ultrasound

1 min read

A team of researchers from the University of Queensland (UQ) have combined modern nanofabrication and nanophotonics techniques to build ultraprecise ultrasound sensors on a silicon chip.

According to the team, the discovery could revolutionise everything from medical devices to unmanned vehicles.

Ultrasound emitters and receivers (sensors) are used in many applications, ranging from medical diagnosis; medical imaging; and range finding and proximity detecting in avionic and automotive industries.

However, to improve these applications, smaller, higher precision sensors are needed – and the UQ researchers believe that they have developed such a device affording greater precision in detecting smaller objects and increasing the resolution, according to research leader Dr. Sahar Basiri-Esfahani.

However, as Dr. Basiri-Esfahani explained to NE, this has been challenging with conventional technologies of ultrasound sensing. As such, the team were inspired to use the recently emerged nano-photonics technology to design and fabricate ultrasound sensors with very high precision and sensitivity.

“This is because the nano-photonics uses light (as opposed to electric current in electronic devices) and very small and delicate optical systems barely visible by eyes. Such sensors would suffer less by the environmental noise,” explained Dr. Basiri-Esfahani.

The new technology is so sensitive that it can hear, for the first time, the miniscule random forces from surrounding air molecules, according to the researchers from QU.

"We're now able to measure ultrasound waves that apply tiny forces - comparable to the gravitational force on a virus - and we can do this with sensors smaller than a millimetre across,” said Prof. Bowen.

The accuracy of the technology could change how scientists understand biology. "We'll soon have the ability to listen to the sound emitted by living bacteria and cells," said Dr. Basiri-Esfahani. “This may improve our understanding of how these small biological systems function, ultimately leading to new treatments.”

The sensor could also be used to increase the precision and sensitivity of ultrasonic range finders in automotive industries, robotics and avionics. The superior sensitivity of this sensor means that you will be able to park your car easier in smaller spaces, the team added.

Because the sensor uses an optical probe (as opposed to electrical ones), it can also survive harsh environments such as high temperatures or extreme electromagnetic or radioactive radiations. For example, in space technologies (satellites, rovers, etc) robust and precise devices such as this sensor are required.

This sensor is believed to be the first example of using a nano-fabricated photonics device for ultrasound sensing. “It may find its way in the so-called photoacoustic imaging which is a non-aggressive technique to image tissue, cancer cells and anomalies,” concluded Dr. Basiri-Esfahani.