A universal Moiré effect and application in x-Ray phase-contrast imaging

Published

April 25, 2016

Author(s)

Houxun Miao, Alireza Panna, Andrew A. Gomella, Eric E. Bennett, sami Znati, Lei Chen, Han Wen

Abstract

A moiré pattern is created by superimposing two black-and-white or gray-scale patterns of regular geometry, such as two sets of evenly spaced lines. We observed an analogous effect between two transparent phase masks in a light beam which occurs at a distance. This phase moiré effect and the classic moiré effect are shown to be the two ends of a continuous spectrum. The phase moiré effect allows the detection of sub-resolution intensity or phase patterns with a transparent screen. When applied to x-ray imaging, it enables a polychromatic far-field interferometer (PFI) without absorption gratings. X-ray interferometry can non-invasively detect refractive index variations inside an object. Current bench-top interferometers operate in the near field with limitations in sensitivity and x-ray dose efficiency. The universal moiré effect helps overcome these limitations and obviates the need to make hard x-ray absorption gratings of sub-micron periods.

Citation

Nature Physics

Volume

12

Issue

9

Pub Type

Journals

Download Paper

https://doi.org/10.1038/nphys3734

Local Download

Keywords

x-ray, phase, imaging

Citation

Miao, H. , Panna, A. , Gomella, A. , Bennett, E. , Znati, S. , Chen, L. and Wen, H. (2016), A universal Moiré effect and application in x-Ray phase-contrast imaging, Nature Physics, [online], https://doi.org/10.1038/nphys3734, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=920684 (Accessed April 25, 2024)