Researchers develop an all-seeing eyeApril 10th, 2008 - 3:01 pm ICT by admin
London, April 10 (IANS) Ever heard of terahertz waves? These higher-frequency waves can penetrate wood ceramics, paper plastic and liquids, making for an ideal tool to detect explosives or drugs, without ripping open suitcases, or searching through items of clothing. It will also enable doctors to identify skin cancer without performing a biopsy.
Terahertz waves change when passing through gases, solid materials or liquids, which may be explosives, water, heroin or blood, carrying their specific imprints.
In a breakthrough, researchers at Fraunhofer Institute for Physical Measurement Techniques IPM succeeded in making these devices mobile.
They have used a femtosecond laser to generate terahertz waves, which move forward by the width of a hair. The pulsed light is directed at a semiconductor, where it excites electrons to emit terahertz waves.
In conventional equipment, laser light moves freely through the room, which makes measurement susceptible to vibrations. Fraunhofer experts have taken a different approach, guiding the light through a glass fibre of a type similar to that used for transmitting data.
“Our fibre-based system is so robust that we can simply plug it into a standard 240-volt socket,” said IPM expert Joachim Jonuscheit.
The advantages are obvious: The transmitters and receivers, which are about the size of beverage cans, are now attached to a flexible cable and can be positioned wherever desired.
Since vibrations are no longer a problem, the device can even be deployed on the factory floor with forklift trucks driving around and heavy machinery vibrating.
Tags: beverage cans, biopsy, conventional equipment, electrons, femtosecond laser, flexible cable, forklift trucks, frequency waves, glass fibre, heavy machinery, higher frequency, imprints, laser light, liquids, physical measurement techniques, seeing eye, skin cancer, solid materials, suitcases, terahertz