have many uses in an array of industries. In medicine, ultrasound is
used to peek at babies to measure their development, or to detect and
sometimes destroy various types of crystalline “stones” in
organs. In manufacturing, ultrasonics can pinpoint microscopic stress
fractures that may introduce flaws or weaknesses to a structure, or
accurately measure surface and sub-surface topographies.
machine refinements have come across the DailyTech desks
in the past, but a new type of device may herald a new approach to
ultrasonic devices as well as dramatically expand their uses.
Researchers at the University of Nottingham have created not a
machine, but nanoscale particles capable of acting as transducers.
Along with the amazingly small size of the multilayer particle, the
simplicity of the system is also quite surprising.
particles, which are constructed as a sandwich of materials to give
them both optical and ultrasonic resonances, can presently be made as
small as around 100 nanometers – about 1/500th the width of a human
hair. Laser light is used to induce ultrasonic vibration in the
particles, which sends out sound waves into the surrounding
environment. The waves reflected back to the particle slightly deform
it, changing its optical properties. This change is then measured by
the laser and could be used to look at the area around the particle
in the same way that modern ultrasound machines use sound itself to
produce a picture.
particles’ future will not be that of simple ultrasound machines
though, explains Dr. Matt Clark of Nottingham’s Applied Optics
Group in a University of Nottingham press
release. “In addition the transducers can be made into highly
sensitive chemical sensors — ultrasonics SAW sensors are used on
the normal scale for electronic noses — this would allow you to
distribute chemical sensors in tissue or in paint — so you could
make paint with chemical sensors to detect corrosion or explosives in