AFRL Program Results in Unique Terahertz Source for Scanning Published June 14, 2013 By Robert White Office of Scientific Research ARLINGTON, Virginia -- An Air Force Research Laboratory-funded program at Microtech Instruments, Inc. resulted in a uniquely capable terahertz source that can be employed in airport scanning. The Terahertz Parametric Oscillator (TPO-1500) averages up to 0.1 mW of power, but significantly, its central 1.5 THz wavelength, combined with a spectral width of 100 GHz, makes it perfectly suited to carry out terahertz imaging. Initially funded by the Defense Advanced Research Projects Agency (DARPA) in 2004, the program transitioned to AFOSR in 2008 under a Small Business Technology Transfer (STTR) grant, a program aimed at supporting the government's research and development efforts via small, high-tech, innovative businesses. Microtech Instruments worked with research teams at Oregon State and Stanford universities to design and refine the operation of the TPO-1500, resulting in the generation of 20 times more terahertz power concentrated in a narrow spectral range, enabling much higher spectral brightness compared to other optical THz sources. Given its very high peak power, the TPO-1500 can be employed as an imaging system employing nonlinear optical effects as well as the ability to carry out thermal detector array imaging--such as airport scanning. At its most basic, terahertz imaging refers to electromagnetic waves operating in a frequency spectrum that has the capability to penetrate a wide range of non-conducting materials, passing through paper, cloth, wood, plastic, and even ceramics, though it cannot penetrate metals or water. Its attributes, even with its shortcomings, make terahertz imaging an ideal candidate for certain medical, security, communication, manufacturing and scientific applications.