Phase-locked single pixel imaging

Abstract

Single-pixel imaging, which is recognized for its high sensitivity and wide spectral range, has a great potential for development in many fields. However, noise from ambient light and detector poses great challenges to its application. In this work, we present a phase-locked single pixel imaging (PL-SPI) technique that uses a lock-in amplifier (LIA) as detector. With the assistance of tunable illumination, the LIA can extract both amplitude and phase from weak signals. It enables the PL-SPI system to reconstruct images under condition of very low signal-to-noise ratio (<−52 dB) and to reconstruct three-dimensional (3D) information with a thickness resolution of approximately 3 mm. It is anticipated that PL-SPI will provide a promising solution for weak signal and 3D imaging applications.