Terahertz computed tomography using a large-format, real-time focal plane array sensor

Sub-millimeter scale image resolution afforded by the THz frequency band, coupled with the ability of THz waves to penetrate through packaging materials have sparked significant interest in THz frequencies for security screening. Conventionally, large-format THz images have been solely acquired using a raster scan of a single pixel, taking several minutes to create a single 2D image of a stationary scene. For stand-off screening applications, coherent THz radars with bulky reflector antennas and fast 2D scanning optics (via rotating mirrors) have cut the imaging time down to several frames per second (K. B. Cooper, IEEE Trans. on Terahertz Science and Technology, vol. 1, no 1, Sept. 2011). Nonetheless, the image resolution and the noise of the acquired images have yet to produce acceptable performance.