Abstract-Compressed sensing with near-field THz radiation

Rayko I. Stantchev, David B. Phillips, Peter Hobson, Samuel M. Hornett, Miles J. Padgett, and Euan Hendry

https://www.osapublishing.org/optica/abstract.cfm?uri=optica-4-8-989&origin=search

We demonstrate a form of near-field terahertz (THz) imaging that is compatible with compressed sensing algorithms. By spatially photomodulating THz pulses using a set of shaped binary optical patterns and employing a 6-μm-thick silicon wafer, we are able to reconstruct THz images of an object placed on the exit interface of the wafer. A single-element detector is used to measure the electric field amplitude of transmitted THz radiation for each projected pattern, with the ultra-thin wafer allowing us to access the THz evanescent near fields to achieve a spatial resolution of ∼9  μm$\sim 9\mathrm{\mu m}$ (𝜆/45$\lambda /45$ at 0.75 THz). We conclude by experimentally improving the image rate by a factor of ∼3$\sim 3$ by undersampling the object with adaptive and compressed sensing algorithms.

Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.