International Conference on Infrared, Millimeter, and Terahertz Waves – Terahertz for Life
Terahertz extends from frequencies of 0.3THz (a wavelength of 1 mm) to 10 THz (30 micrometers) which offer unique imaging properties. The short wavelengths of terahertz rays provide enough spatial resolution for 3D micro imaging. Also, they don’t have physiological damaging effects as X-rays.
There are several ways to generate terahertz waves. Lasers are the preferred method. Laser light can control at a high level the spectral and temporal elements.
In the exhibit area were several companies with systems for controlling terahertz signals for commercial and research applications. There was Loeffler-Technology which performs mm-wave imaging with terahertz signals for package inspection and security exploration. The demo unit showed a terahertz signal that could measure the both sides of a box with a single scan and thus providing a near 3D image of it. It could also detect hidden weapons such as a gun hidden underneath clothing. The product is called SynViewScan 300.
Another group called Toptica Photonics which makes tunable diode lasers. Their research shows that the optical beat frequency of two slightly detuned CW lasers lies in the terahertz region. Through the accurate frequency control of two seed lasers, they can produce a narrow-band tunable terahertz beat frequency.
Emcore makes fiber optic equipment and uses terahertz in their systems for spectroscopy measurements.