Besides having to remove our shoes, the volume limitations regarding liquids and gels in carry-on baggage has become a major hassle in the world of post 9-11 airport security. Hopefully, however, we may soon be able to once again bring our big bottles of water and tubes of toothpaste aboard airliners in our overnight bags. Britain's Cobalt Light Systems has developed a scanner called the INSIGHT100, that uses laser light to assess the liquid contents of containers, even if those containers are opaque.
The scanner utilizes Spatially Offset Raman Spectroscopy, or SORS. The process begins with security personnel placing an individual container inside the microwave oven-sized device. Then, the system shines a near-infrared laser into that container at various locations. Some of that light is reflected back to the device by the liquid. The wavelength of that light, however, is shifted by energy levels of the liquid's molecules. By assessing the wavelength shifts of those various light readings, the machine is able to identify what the liquid is - within five seconds, to boot.
The INSIGHT100 reportedly has a false alarm rate of less than 0.5 percent, and works with clear, colored or opaque plastic or glass containers. It can be used on bottles up to three liters (0.8 US gallons) in size, and the height of its reading device can be adjusted for partially-filled containers. Additionally, its library of various liquids' SORS signatures can be continuously updated, to recognize newly-identified security threats.
According to Cobalt, the scanner recently passed its European civil aviation security tests, which means it could start showing up in airports sometime soon.
The video below shows how the INSIGHT100 is to be used.
Source: Cobalt Light Systems via New Scientist