A single-pixel terahertz imaging system based on compressed sensing

TLDR

Compressed sensing theory allows reconstruction of an N‑by‑N image from far fewer than N² measurements, and this approach can be applied to both pulsed and continuous‑wave terahertz sources. The study presents a terahertz imaging system that uses a single‑pixel detector with random masks for high‑speed acquisition. The system employs a single‑pixel detector with random masks and is implemented on a pulsed terahertz time‑domain platform, enabling reconstruction of amplitude and phase‑contrast images. The method removes raster scanning while preserving detector sensitivity, and successfully reconstructs amplitude and phase‑contrast images in a pulsed terahertz time‑domain experiment.

Abstract

We describe a terahertz imaging system that uses a single pixel detector in combination with a series of random masks to enable high-speed image acquisition. The image formation is based on the theory of compressed sensing, which permits the reconstruction of a N-by-N pixel image using much fewer than N2 measurements. This approach eliminates the need for raster scanning of the object or the terahertz beam, while maintaining the high sensitivity of a single-element detector. We demonstrate the concept using a pulsed terahertz time-domain system and show the reconstruction of both amplitude and phase-contrast images. The idea of compressed sensing is quite general and could also be implemented with a continuous-wave terahertz source.