Tiny sensors 500 times smaller than the thickness of a human hair could be the key to the future of ultrasound imaging.
Researchers at the University of Nottingham have developed the nanoscale sensors, which are so small that they can be inserted into cells to picture them from within.
Despite their tiny size, the devices are powerful - they can output sound at a frequency higher than that of visible light.
This results in a tiny wavelength, meaning the image obtained could potentially be of finer detail than any optical microscope is currently able to produce.
Matt Clark of the Applied Optics Group, which conducted the research, says: "With the rise of nanotechnology you need more powerful diagnostic tools, especially ones that can operate non-destructively."
He adds that devices must be capable of assessing the chemical and mechanical characteristics of a sample at the nanometre scale.
The university's division of electrical systems and optics conducts research in four broad fields, comprising biomedical applications, microscopy and optics, integrated sensors and laser ultrasonics.