Secondary complementary balancing compressive imaging with a free-space balanced amplified photodetector

TL;DR

This paper introduces a secondary complementary balancing method in single-pixel imaging that uses a balanced photodetector to improve measurement quality and image reconstruction by reducing imbalance effects.

Contribution

It proposes a simple secondary balancing mechanism for SPI systems that enhances measurement accuracy and image quality by minimizing arm imbalance effects.

Findings

Improved signal-to-noise ratio in measurements.

Enhanced image reconstruction quality.

Effective cancellation of direct current components.

Abstract

Single-pixel imaging (SPI) has attracted widespread attention because it generally uses a non-pixelated photodetector and a digital micromirror device (DMD) to acquire the object image. Since the modulated patterns seen from two reflection directions of the DMD are naturally complementary, one can apply complementary balanced measurements to greatly improve the measurement signal-to-noise ratio and reconstruction quality. However, the balance between two reflection arms significantly determines the quality of differential measurements. In this work, we propose and demonstrate a simple secondary complementary balancing mechanism to minimize the impact of the imbalance on the imaging system. In our SPI setup, we used a silicon free-space balanced amplified photodetector with 5 mm active diameter which could directly output the difference between two optical input signals in two reflection arms. Both simulation and experimental results have demonstrated that the use of secondary complementary balancing can result in a better cancellation of direct current components of measurements and a better image restoration quality.