National Physical Laboratory


Microwaves are used in everyday life for cooking, communications and radar. The type and application of microwaves are dictated by their frequency, measured in units of Gigahertz (GHz). For example, microwave ovens operate at 3 GHz, mobile phones use 2 GHz, aircraft radars use anything from 20 to 50 GHz and recent collision avoidance technology used in Mercedes automobiles operates at 94 GHz. Once frequencies reach more than a few hundred Gigahertz the radiation becomes known as Terahertz radiation.

Further increases in frequency produce radiation known as infrared, optical, and visible light. The gap between the microwave and optical radiation frequencies is often referred to as the Terahertz gap and has recently been shown to have some very useful applications in medical imaging, security screening, materials testing and understanding biological processes in proteins and DNA.

The Terahertz (THz) gap, has remained relatively unexplored due to limitation in generating, detecting and manipulating the radiation. Interestingly, hot objects emit Terahertz radiation, including humans and animal, but achieving good control and high output power is experimentally difficult.

If you would like to register your interest in attending an NPL Introduction to Terahertz Workshop, please e-mail

For more information please contact: Richard Dudley

NPL has been active in Terahertz metrology for more than 30 years, with a large amount of work undertaken on DFTS and Far-infrared spectroscopy.
Terahertz radiation can see weapons, explosives, and drugs hidden under people's clothes.

Terahertz collaboration

Presentations from an introductory workshop about terahertz and its applications.


Please note that the information will not be divulged to third parties, or used without your permission