Negative influence of detector noise on ghost imaging based on the photon counting technique at low light levels

The influence of detector noise on ghost imaging (GI) is investigated at low light levels. Based on the characteristics of the additive detector noise, we establish the analytical model and display the ghost images through numerical and experimental demonstrations. It is shown that the contrast-to-noise ratio and visibility of reconstructed images are sharply affected by the detector noise. Following the increase of the ratio of average signal intensity to the average noise, the quality of reconstructions is enhanced. To reduce the measurement numbers and, thus, shorten the consuming time without sacrificing the imaging quality, we propose a sorting technique in the traditional GI algorithm for a high quality image reconstruction. The results demonstrated here will be favorable to the applications of low-light-level imaging.