Klaus Juergen Engel;Gereon Vogtmeier;Dieter Geller
发明人:
Klaus Juergen Engel,Dieter Geller,Gereon Vogtmeier
申请号：
US13319527
公开号：
US08855265B2
申请日:
2010.06.10
申请国别(地区):
US
年份:
2014
代理人:
摘要：
The present invention generally refers to a correction method for grating-based X-ray differential phase contrast imaging (DPCI) as well as to an apparatus which can advantageously be applied in X-ray radiography and tomography for hard X-ray DPCI of a sample object or an anatomical region of interest to be scanned. More precisely, the proposed invention provides a suitable approach that helps to enhance the image quality of an acquired X-ray image which is affected by phase wrapping, e.g. in the resulting Moiré interference pattern of an emitted X-ray beam in the detector plane of a Talbot-Lau type interferometer after diffracting said X-ray beam at a phase-shifting beam splitter grating. This problem, which is further aggravated by noise in the obtained DPCI images, occurs if the phase between two adjacent pixels in the detected X-ray image varies by more than π radians and is effected by a line integration over the object's local phase gradient, which induces a phase offset error of π radians that leads to prominent line artifacts parallel to the direction of said line integration.
