Using cyclic Hadamard masks for single-pixel quantum imaging under entangled photon illumination

Abstract

Quantum imaging, operating at extremely low photon flux and accommodating nondegenerate imaging wavelengths, offers a unique approach for imaging light-sensitive structures. Conventional quantum imaging systems often require costly intensified charge-coupled devices together with complex delay line and triggering electronics, limiting broader applications. In this work, we propose an approach for quantum imaging that uses a simple rotating mask coded with cyclic Hadamard patterns, together with single-pixel detectors, eliminating the need for the abovementioned specialized devices. Single-pixel quantum imaging with a resolution of 41 pixels by 43 pixels is performed, and its noise-resistant performance is further studied with an improved gate time of 1 nanosecond using time-correlated single-photon counting. An imaging speed up to 2 frames per second can be achieved, corresponding to a spatial modulation rate of 3.8 kilohertz. Furthermore, quantum ghost imaging with the object and the mask modulation in separate beams is also demonstrated, showing the potential of our system for high-speed, low-cost, and noise-resistant quantum imaging applications.

Fig. 1.. Components of the single-pixel quantum imaging system.

(A) Experimental schematic for the single-pixel quantum imaging system using a rotating mask coded with cyclic Hadamard patterns, where locations A and B correspond to SPI and quantum ghost imaging configurations, respectively. (B) Designed binary mask in rectangular shape. (C) Designed annular mask based on (B). (D) Image of the manufactured circular mask. HWP, half-wave plate. LP, long pass.

Fig. 2.. Data processing methodology for image reconstruction.

The sampled signal is processed in three sequential steps: (A) Sampling the periodic photon-counting signal from the TCSPC module. (B) Extracting a single-cycle signal after removing the signal marker. (C) Deriving one-dimensional spatial data through FFT processing. (D) Reconstructing a two-dimensional image by reshaping the processed one-dimensional spatial data.

Fig. 3.. Experimental results of single-pixel quantum imaging under noise interference.

(A) Baseline image acquired under laser illumination conditions with a long exposure time. (B) Reconstructed images using the quantum imaging method and (C) the direct imaging method at noise levels of 0, 10, 25, 100, and 800 kcps, presented from left to right. (D) Calculated SNR of the reconstructed images at varying noise levels.

Fig. 4.. Experimental results of dynamic imaging.

(A) Image template. (B) Images of the object captured at different positions across the field of view of our system.

Fig. 5.. Experimental results of quantum ghost imaging.

(A) Template images. Reconstructed images of (B) single-pixel quantum imaging and (C) single-pixel quantum ghost imaging.