 Terahertz imaging has advantages over the more expensive and shorter range X-ray scanners.A variety of materials are transparent to terahertz radiation, which allows it to measure the thickness, density, and structural properties of materials that are difficult to detect.Since terahertz is not ionizing radiation, the use of terahertz does not cause damage to living tissue, making terahertz a safe, non-invasive biomedical imaging technique.