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 wave imaging has been used in various applications, such as security sensing and quality control inspection, for example. Terahertz wave two-dimensional (2D) imaging technology has been demonstrated as it dramatically reduces the time required for image acquisition. It can also support real-time terahertz wave imaging.
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.
This invention is directed to techniques for obtaining and imaging three-dimensional objects using radiation in the terahertz (THz) spectrum and systems and associated methods for high resolution terahertz computed tomography. Although computed tomography is well known in X-ray radiographic imaging, a serious problem in reconstructing an image using THz computed tomography is that the THz wave does not satisfy the short wave limit as the X-ray satisfies in X-ray computed tomography.
Terahertz (THz) waves occupy a segment of the electromagnetic spectrum between the infrared and microwave bands. As such, they can be used for imaging and sensing in ways that are not possible with conventional technologies such as X-ray and microwave. Because THz radiation transmits through almost anything that is not metal or liquid, the waves can see through most materials that might be used to conceal explosives or other materials, such as packaging, corrugated cardboard, clothing, shoes, backpacks, and book bags. They are also safer than X-rays and microwaves for human tissue.