Abstract:
:Refraction contrast of simple objects obtained using diffraction enhanced imaging (DEI) was studied and compared to conventional radiographic contrast. Lucite cylinders and nylon wires were imaged using monochromatic synchrotron radiation at the National Synchrotron Light Source (http://nslsweb. nsls.bnl.gov/nsls/Default.htm) at the Brookhaven National Laboratory. The DEI images were obtained by placing a silicon analyser crystal tuned to the [333] diffraction plane in the beam path between the sample and the detector. To compare the DEI images with conventional radiographic images requires a consistent definition of refraction and absorption contrast. Conventional definitions of contrast favour conventional radiography and DEI contrast is defined to emphasize the specific characteristics of DEI. The proposed definitions were then used to find the DEI gain (the ratio of the DEI contrast with respect to the conventional image contrast). The results presented here show that the DEI gain is consistently greater than 1, indicating that DEI provides more contrast information than conventional radiography.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Kiss MZ,Sayers DE,Zhong Zdoi
10.1088/0031-9155/48/3/304subject
Has Abstractpub_date
2003-02-07 00:00:00pages
325-40issue
3eissn
0031-9155issn
1361-6560journal_volume
48pub_type
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