Link Microtek, a specialist supplier of microwave components and systems, has introduced a new liquid identification system that could enable airport authorities to lift restrictions on passengers carrying bottles of liquid in their hand luggage. Known as EMILI 1+, the system uses an innovative microwave sensing technique to instantly identify whether the contents of a bottle are completely harmless, inflammable, corrosive or explosive.

Originally developed by German company Emisens (a spinout from the Jülich Research Centre), the system is now available worldwide through the company's sales, service and R&D partner, Link Microtek. As well as promoting and providing service support for the EMILI 1+ system, Link Microtek now has a financial stake in Emisens and is using its in-house design and manufacturing facilities to help in the development of new EMILI products.

At the heart of the EMILI 1+ system is a multimode sensor emitting an evanescent microwave field that penetrates the bottle under test and enables the dielectric permittivity and ionic conductivity of the unknown liquid to be measured. From these parameters, the system identifies the type of liquid in the bottle and immediately displays the result on the screen.

The whole process takes less than one second, which makes the EMILI 1+ particularly attractive for security checkpoints, where speed of operation is a vital consideration. The system works with plastic, glass and ceramic bottles, which are simply placed unopened on the machine. It is suitable for use as a standalone system or in conjunction with existing X-ray scanners, which generally have very limited capability for identifying liquids but has none of the health-and-safety concerns associated with X-ray equipment.