OREANDA-NEWS. Physicists have created a unique device - an ultrasonic detector of record small size. This achievement has been described in detail in the scientific magazine Nature. It is one hundred times smaller than the thickness of a human hair. The device can make ultrasound images almost as detailed as if they were taken under a microscope.

Ultrasound scanners were invented about 70 years ago, and since that time they have been widely used in science and medicine.

 Extremely small sensors can obtain a very detailed image. However, the size of ultrasonic sensors is difficult to reduce: along with their size, their sensitivity to ultrasound decreases as well. Therefore, the smallest devices of such type are about one millimeter in size.

That is why the authors of the new study used the quite different physical principle. They created a silicon sensor in which a light wave travels along a specially designated path. When ultrasound deforms the sensor, the light intensity is affected.

Physicists called their invention a “silicon waveguide-etalon detector, or SWED”.  It is fantastically small: it is not more than 0.5 micrometers, so it’s smaller than a blood cell. And images obtained during ultrasound diagnostics with this detector will allow scientists to examine the internal organs as well as subtle technical devices as if under a microscope.