A wide spectral and intensity range single-pixel imaging system

Single-pixel imaging (SPI) has the advantage of high detection sensitivity, which has great potential for imaging in low light. However, they still have some limitations; high sensitivity and high gain amplify noise as well as the signal, which results in poor image quality and low dynamic range. In this paper we implement a dual-band wide dynamic range SPI system that can simultaneously achieve near-infrared and visible light imaging at femtowatt levels, with an average of 3–17 fW incident on two Geiger-mode avalanche photodiodes. Time gating is employed to block unwanted noise; a contrast-to-noise ratio greater than 2 over a wide dynamic range of 0.006–1.08 mW/cm² is achieved. Our system demonstrates an effective strategy for imaging under ultra-low-level illumination, and should find many applications in both research and industry.