X-ray phase contrast imaging is a promising technique in X-ray biological microscopy, as it improves the contrast of images for materials with low electron density compared to traditional X-ray imaging. The spatial resolution is an important parameter to evaluate the image quality. In this paper, simulation on factors which may affect the spatial resolution in a typical 2D grating-based phase contrast imaging system is conducted. This simulation is based on scalar diffraction theory and the operator theory of imaging. Absorption, differential phase contrast and dark-field images are retrieved via the Fourier transform method. Furthermore, the limitation of the grating-to-detector distance in the spatial harmonic method is discussed in detail.

中文翻译：

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影响基于二维光栅的X射线相衬成像中空间分辨率的因素

X射线相衬成像是X射线生物显微镜中的一项有前途的技术，因为与传统X射线成像相比，它提高了电子密度低的材料的图像对比度。空间分辨率是评估图像质量的重要参数。在本文中，对可能影响典型的基于2D光栅的相衬成像系统中空间分辨率的因素进行了仿真。该模拟基于标量衍射理论和成像算符理论。吸收，微分相位对比和暗场图像通过傅立叶变换方法获得。此外，详细讨论了空间谐波方法中光栅到检测器距离的限制。