基于分块平滑投影二次重构算法的单像素成像系统

单像素成像系统是通过无空间分辨能力的单像元探测器来获取目标二维分布信息的计算光学成像技术，与传统直接成像技术相比具有高能量收集效率、高灵敏度等一系列优点，在高能物理诊断技术领域有着广阔的应用前景。针对实际单像素压缩感知成像系统在复杂诊断环境中存在的重建噪声较大的问题，提出并实现了基于分块平滑投影Landweber二次重构算法的单像素成像系统。根据算法观测矩阵分布特性以及数字微镜硬件输入要求实现了实际投影观测矩阵的变换，利用二次重构算法实现了单像素诊断的仿真分析与实验测试。仿真结果表明，在采样率为20%～30%的条件下，重建图像峰值信噪比大于20 dB，结构相似性高于0.8。进一步搭建单像素成像平台完成实验研究及验证，实验结果表明，利用二次重构算法模型对目标场景进行恢复的效果优于其余两种传统算法。二次重构单像素成像系统在采样率仅为20%的条件下能够重建出清晰的原始图像，具有较好的噪声抑制特性。

Single-pixel imaging system based on block smoothed projected quadratic reconstruction algorithm

The single-pixel imaging system is a computational optical imaging technology that obtains the two-dimensional distribution information of the target through a single-pixel detector without spatial resolution. Compared with traditional direct imaging technology, it has a series of advantages such as high energy collection efficiency and high sensitivity. In the field of high-energy physical diagnosis technology it has broad application prospects. Aiming at the problem that the actual single-pixel compressed sensing imaging system has large reconstruction noise in complex diagnostic environments, this paper proposes and implements a single-pixel imaging system based on the block smooth projection Landweber quadratic reconstruction algorithm. According to the distribution characteristics of the algorithm's observation matrix and the digital micromirror hardware input requirements, the transformation of the actual projection observation matrix is realized, and the simulation analysis and experimental test of the single-pixel diagnosis are realized by using the quadratic reconstruction algorithm. The simulation results show that under the condition of a 20% to 30% sampling rate, the peak signal-to-noise ratio of the reconstructed image is greater than 20 dB, and the structural similarity is higher than 0.8. The single-pixel imaging platform is further built to complete the experimental research and verification. The experimental results show that the recovery effect of the target scene using the quadratic reconstruction algorithm model is better than the other two traditional algorithms. The quadratic reconstruction single-pixel imaging system can reconstruct a clear original image with a sampling rate of only 20%, and has good noise suppression characteristics.