According to a press release today, researchers at UC Berkeley (go bears!) have developed a new material that is able to overcome some of the limits of modern ultrasound technology:
The substance, dubbed an “ultrasonic metamaterial,” responds differently to sound waves than any substance found in nature. Within a decade, the researchers report, the technology they developed to create the material could be used to vastly enhance image resolution of ultrasound, while at the same time allowing for the miniaturization of acoustic devices at any given frequency…
The study, “Ultrasonic metamaterials with negative modulus,” will be published June 1 in Nature Materials. The journal released the study in its early online version on April 30…
One of the factors limiting resolution quality of sonograms is the ability of the ultrasound lens to capture sound waves. Currently, these lenses are made with elastic materials such as polymers. The elasticity of the materials is what allows them to capture and focus the waves. But there is a limit to the finest resolution that they can capture.
“With this new material with a negative modulus, all the limits can be overcome,” Fang said.
The material that Zhang’s research group fabricated is 55 centimeters long and houses 60 resonators. [Xiang Zhang, Professor in Mechanical Engineering at UC Berkeley -ed.] In its present form, it can be used only for one frequency and can capture sound from only one direction. The group’s plan, said Zhang, is to develop “three-dimensional” materials that will not only be able to capture sound from every direction, but will also be tunable. That is, the size of the resonators will be adjustable so that the material can respond to any frequency. Once they have designed and tested such a material, Zhang expects to be able to use microfabrication techniques to build materials with hundreds of thousands of resonators.
Because its resonators are many times smaller than wavelengths of the sound wave, Zhang said, the material can be used to make compact sonar and ultrasonic devices. Conventional lenses in these devices must be at least as large as the waves they are meant to capture. Sonar devices, which use long-length waves, would particularly benefit from this miniaturization.
Non-invasive imaging like ultrasound is bursting with innovation and technological progress. Keep checking Medgadget.com for more exciting ultrasound updates, and be sure to check out our post about plug-and-play ultrasound.
Read the full press release here…