中国物理B ›› 2017, Vol. 26 ›› Issue (2): 28701-028701.doi: 10.1088/1674-1056/26/2/028701

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Shifting curves based on the detector integration effect for x-ray phase contrast imaging

Jun Yang(杨君), Jin-Chuan Guo(郭金川), Yao-Hu Lei(雷耀虎), Ming-Hao Yi(易明皓), Li Chen(陈力)   

  1. Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
  • 收稿日期:2016-08-26 修回日期:2016-11-01 出版日期:2017-02-05 发布日期:2017-02-05
  • 通讯作者: Jin-Chuan Guo E-mail:jcguo@szu.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11074172 and 11674232), the National Key Basic Research Program, China (Grant No. 2012CB825804), and the National Special Foundation for Major Science Instrument, China (Grant No. 61227802).

Shifting curves based on the detector integration effect for x-ray phase contrast imaging

Jun Yang(杨君), Jin-Chuan Guo(郭金川), Yao-Hu Lei(雷耀虎), Ming-Hao Yi(易明皓), Li Chen(陈力)   

  1. Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
  • Received:2016-08-26 Revised:2016-11-01 Online:2017-02-05 Published:2017-02-05
  • Contact: Jin-Chuan Guo E-mail:jcguo@szu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11074172 and 11674232), the National Key Basic Research Program, China (Grant No. 2012CB825804), and the National Special Foundation for Major Science Instrument, China (Grant No. 61227802).

摘要: In theory, we find that the actual function of the analyzer grating in the Talbot-Lau interferometer is segmenting the self-images of the phase grating and choosing integral areas, which make sure that each period of self-images in one detector pixel contributes the same signal to the detector. Furthermore, in the case of the lack of an analyzer grating, the shifting curves are still existent in theory as long as the number of fringes is non-integral in a detector pixel, which is a sufficient condition for creating shifting curve. The sufficient condition is available for not only the Talbot-Lau interferometer and the inverse geometry of Talbot-Lau interferometer, but also the x-ray phase contrast imaging system based on geometrical optics. In practical applications, we propose a method to improve the performances of the existing systems by employing the sufficient condition. This method can shorten the system length, is applicable to large period gratings, and can use the detectors with large pixels and large field of view. In addition, the experimental arrangement can be simplified due to the lack of an analyzer grating. In order to improve detection sensitivity and resolution, we also give an optimal fringe period. We believe that the theory and method proposed here is a step forward for x-ray phase contrast imaging.

关键词: x-ray phase contrast imaging, Talbot-Lau interferometer, x-ray imaging

Abstract: In theory, we find that the actual function of the analyzer grating in the Talbot-Lau interferometer is segmenting the self-images of the phase grating and choosing integral areas, which make sure that each period of self-images in one detector pixel contributes the same signal to the detector. Furthermore, in the case of the lack of an analyzer grating, the shifting curves are still existent in theory as long as the number of fringes is non-integral in a detector pixel, which is a sufficient condition for creating shifting curve. The sufficient condition is available for not only the Talbot-Lau interferometer and the inverse geometry of Talbot-Lau interferometer, but also the x-ray phase contrast imaging system based on geometrical optics. In practical applications, we propose a method to improve the performances of the existing systems by employing the sufficient condition. This method can shorten the system length, is applicable to large period gratings, and can use the detectors with large pixels and large field of view. In addition, the experimental arrangement can be simplified due to the lack of an analyzer grating. In order to improve detection sensitivity and resolution, we also give an optimal fringe period. We believe that the theory and method proposed here is a step forward for x-ray phase contrast imaging.

Key words: x-ray phase contrast imaging, Talbot-Lau interferometer, x-ray imaging

中图分类号:  (X-ray imaging)

  • 87.59.-e
07.60.Ly (Interferometers) 42.30.Rx (Phase retrieval) 87.57.-s (Medical imaging)