Reconstruction of point spread function of incoherent light by redundant information extraction and its application in synchrotron radiation imaging system [非相干光点扩散函数的重建及其在同步辐射成像系统中的应用]

作者：Xia H.; Wu Y.; Zhang L.; Sun Y.; Tai R.^*

来源：Nuclear Techniques, 2020, 43(1): 010101.

DOI：10.11889/j.0253-3219.2020.hjs.43.010101

• Information redundancy
• Point spread function
• Scintillator imaging
• X-ray

[Background]: The point spread PSF) of X-ray indirect imaging system is difficult to measure accurately through experiments, and the theoretical construction process is complex, hence it is difficult to meet the actual situation, resulting in poor image quality. [Purpose]: This study aims to obtain the PSF of X-ray indirect imaging system by reconstructing PSF with redundant information to obtain a more accurate PSF under incoherent illumination. [Methods]: First of all, theoretical analysis was performed for the measuring problem of incoherent optical PSF. Since the optical transfer OTF) was the fourier transform of PSF, and coherent transfer CTF) was closely related to OTF, nonlocality of incoherent optical information distribution was used to reconstruct the central region of the PSF. Then, the redundent information in a 2D grating scintillation imaging system was extracted to reconstruct the PSF by converting incoherent diffraction field to coherent diffraction field. Finally, experimental data obtained from BL13W beamline station of Shanghai synchrotron radiation facility (SSRF) were employed to evaluate PSF and image restoration results of scintillator imaging system. [Results]: Experimental results of synchrotron radiation imaging show that this method can recover the image more accurately than other PSF measurement methods. [Conclusion]: The PSF reconstructed by redundant information method can not only restore the image accurately, but also avoid a lot of complex problems.

• 单位
  中国科学院大学