Exploiting k-space - frequency duality in Fourier optics towards real-time compression-less terahertz imaging

TL;DR

This paper introduces a novel Fourier optics-based method for real-time, compression-less terahertz imaging that uses k-space and frequency duality, enabling high-resolution imaging with minimal measurements.

Contribution

It presents a new hybrid inverse transform technique exploiting k-space/frequency duality for fast, high-resolution THz imaging without compression, applicable to amplitude and phase contrast images.

Findings

Requires measurements scaling linearly with image size

Handles amplitude and phase contrast equally well

Promises real-time high-resolution THz imaging

Abstract

We present theoretical formulation and experimental demonstration of a novel technique for the fast compression-less terahertz imaging based on the broadband Fourier optics. The technique exploits k-vector/frequency duality in Fourier optics which allows using a single-pixel detector to perform angular scan along a circular path, while the broadband spectrum is used to scan along the radial dimension in Fourier domain. The proposed compression-less image reconstruction technique (hybrid inverse transform) requires only a small number of measurements that scales linearly with the image linear size, thus promising real-time acquisition of high-resolution THz images. Additionally, our imaging technique handles equally well and on the equal theoretical footing the amplitude contrast and the phase contrast images, which makes this technique useful for many practical applications. A detailed analysis of the novel technique advantages and limitations is presented, as well as its place among other existing THz imaging techniques is clearly identified