Structured illumination for super resolution terahertz imaging

Our recent THz imaging system performs full-frame high-speed imaging (12000 fps) by exploiting efficient THz-to-optical conversion in an excited Caesium atomic vapour. Structured Illumination Microscopy (SIM) has revolutionized optical microscopy pushing beyond the diffraction limit. At THz frequencies the diffraction limit is measured on the sub-mm scale therefore would benefit from improvement. Implementing Structured Illumination Super Resolution at the THz regime has previously been unattractive due to the long acquisition times of conventional THz detectors, compounded by the requirement of multiple images for super-resolution image reconstruction. Using our high-speed THz imaging system, we investigate the application of Structured Illumination Super Resolution Imaging as a method to improve spatial resolution, while maintaining the high penetrating properties and high detection sensitivity at 0.55THz.