A new method is proposed to improve the signal-to-noise ratio (SNR) of regions of interest (ROIs) in a ghost imaging (GI) system with uneven speckle illumination. The imaging results in a GI system can be distorted when there is an uneven distribution of light. In this study, three thin-film polarizers are used to create illumination patterns in uneven light intensity distribution. In particular, the polarizer set is loaded on the object arm only, that is, the original uniformly distributed light field is still acquired by the reference arm. This small change in the light path eliminates the distortion caused by uneven illumination while increasing the SNR of the ROI. This strategy has been confirmed in principle and through simulation and experiments.

中文翻译：

---

提高鬼影质量的策略

提出了一种新方法来改善散斑照明不均匀的重影成像（GI）系统中感兴趣区域（ROI）的信噪比（SNR）。当光线分布不均时，GI系统中的成像结果可能会失真。在这项研究中，使用了三个薄膜偏振器来创建不均匀光强度分布的照明图案。特别是，偏振器组仅加载在物镜臂上，也就是说，参考臂仍然可以获取原始均匀分布的光场。光路的这种微小变化消除了照明不均引起的失真，同时提高了ROI的SNR。原则上已经通过模拟和实验确认了该策略。