Phys.org February 10, 2020
Long-wavelength terahertz radiation which is considered to be much safer than X-ray radiation has not been used in security and medical devices because its energy is so low and it has been difficult to create high-resolution images using them. Instead of building a more sensitive sensor researchers in the UK made the waves more readable to conventional technology. They converted the terahertz radiation into green light by directing it into a cloud of excited cesium atoms. Once the cloud was formed, the researchers fired a secondary terahertz laser through a moving object, which allowed a “shadow image” to strike the excited cesium cloud. Conventional high-speed cameras then captured the images as they emerged from the cloud. The combination of speed and sensitivity represents a step change in the state of the art of THz imaging and will likely lead to its uptake in wider industrial settings…read more. TECHNICAL ARTICLE
Terahertz radiation can be used for many kinds of imaging, such as in airports or in nondestructive materials testing. A new technique uses it for high-speed video. Credit: Sequestim/Cardiff University