14.5 A 0.53THz reconfigurable source array with up to 1mW radiated power for terahertz imaging applications in 0.13μm SiGe BiCMOS

Recently, silicon-based THz video cameras have been demonstrated for industrial, surveillance, scientific, and medical applications in the THz range (300GHz to 3THz) [1]. Such camera implementations favor pixels with antenna-coupled direct detectors for a low power dissipation and a high pixel count. Despite this progress, they lack the required sensitivity for passive imaging and imagers are in the need of artificial illumination to provide the required image quality. The choice has been to use expensive high-power focused illumination with a single direction for the incoming beam, which seriously limits the image quality due to its specular nature. Additionally, detectors in a focal-plane array configuration share the available source power and the image SNR further drops with the camera resolution. Like imaging at visible light, where shades or reflectors are commonly used, active THz imaging would greatly benefit from incoherent artificial light sources to adjust brightness, phase/frequency, and the direction of light to obtain the desired lighting conditions.