Post date: Jan 14, 2014 2:43:15 PM
'Smart' contact lenses which monitor the health of patients' eyes could become a reality, according to scientists who have devised flexible, electronic circuits 50 times thinner than a human hair.
ZURICH, SWITZERLAND (RECENT) (ETH ZURICH) - Ultra-thin, flexible, electronic circuits which can be wrapped around a single hair without breaking have been unveiled by researchers at Eidgenössische Technische Hochschule Zurich(ETH Zurich). The team, led by researchers Niko Münzenrieder and Giovanni Salvatore, say these types of components could be woven into textiles to make 'smart' objects, or be applied to the skin as unobtrusive sensors that monitor body functions.
The components have a maximum thickness of 0.001 mm, making them 50 times thinner than a human hair. The clear, flexible electronic circuitry is so thin it can sit upon the surface of a contact lens. Münzenrieder and Salvatore think the technology could eventually be used to create a 'smart contact lens' to monitor intraocular pressure in glaucoma patients' eyes, or to support implantable medical devices.The circuits are created on a substance called parylene, an insulator traditionally used as a protective coating for electronic devices and components. As well as being able to withstand high temperatures, parylene is transparent, bio-compatible, and extremely flexible.
Münzenrieder believes the technology could also be applied to "smart" textiles for sports trainers or in hospitals to monitor body temperature and other physiological factors.
In tests, researchers attached the thin-film transistors to standard contact lenses which they placed on an artificial eye, proving the circuits could withstand the bending radius of the eye without becoming damaged. The team has also shown that the membrane can self-adhere to a wide range of surfaces, including a ficus leaf which, for demonstration purposes, they submerged in water containing pieces of the shiny metallic membrane. On lifting the leaf, the film had stuck like glue.
The team is also working on integrating the components with elastic materials, possibly to create a smart skin for robots or prostheses, although they say the technology is unlikely to be ready for commercial use for at least five years.