This invention is directed to a unique imaging microscope operating within the electromagnetic terahertz frequency regime for medical applications. Unlike optical spectroscopes that only measure the intensity of light at specific frequencies, the terahertz domain allows for the precise measurements of the refractive index and absorption coefficient of samples that interact with the terahertz waves. Various liquids and gases molecules interact within the terahertz frequency band and their unique resonance lines allow their molecular structure to be identified.

Terahertz (THz) radiation occupies a large portion of the electromagnetic spectrum between the infrared and microwave bands and is a developing frontier in imaging science and technology. In contrast to the relatively well-developed techniques for imaging at microwave and optical frequencies, however, there has been only limited basic research, new initiatives, and advanced technology developments in the THz band.