Image via Wikipediahttp://www.wpafb.af.mil/news/story.asp?id=123273562 Robert P. White Air Force Office of Scientific Research 9/26/2011 - ARLINGTON, Va. -- An AFOSR-funded program at Microtech Instruments has resulted in a uniquely capable terahertz source. 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. 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 products, cloth, wood, plastic, and even ceramics. It cannot though, penetrate metals or water. Even with those shortcomings, its attributes make it an ideal candidate for certain medical, security, communication, manufacturing and scientific applications. 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 which is based on difference frequency generation in a quasi-phase-matched Gallium Arsenide crystal placed inside an optical parametric oscillator pumped by an ultrafast fiber laser. This results in the generation of 20 times more terahertz power and more importantly this power is 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. Ultimately this type of technology, employed in terahertz imaging systems, could lead to devices that scan airport passengers far more efficiently. Microtech points out that while the TPO-1500 is likely the first in a series of new products for the company, "...this technology is extendable to higher power sources, covering multiple spectral bands. While this first product is a bread-board-based system suitable only for research labs, it is potentially scalable to more practical applications as well." ABOUT AFOSR: The Air Force Office of Scientific Research (AFOSR), located in Arlington, Virginia, continues to expand the horizon of scientific knowledge through its leadership and management of the Air Force's basic research program. As a vital component of the Air Force Research Laboratory (AFRL), AFOSR's mission is to discover, shape, and champion basic science that profoundly impacts the future Air Force. |
No comments:
Post a Comment