Quantitative phase imaging and complex field reconstruction by pupil modulation differential phase contrast hangwen lu, jaebum chung,xiaoze ou, and changhuei yang department of electrical engineering, california institute of technology, pasadena, ca 91125, usa. The recent advances are going beyond microradiology and. In xray crystallography this is used to image with subangstrom resolution the. Therefore, fresnel diffraction of a given wave field with a discrete nx. Yet, several early experimental results indicate that it has some potential for clinical. Low dose and fast gratingbased xray phasecontrast imaging. Pdf quantitative analysis of contrast to noise ratio using a. As these materials provide in general very limited xray absorption contrast ac. Unlike in conventional xray imaging, in xpci, image contrast is based on the phase shift induced by the object instead of its attenuation. Xray phasecontrast imaging is an important method for visualizing cellular and histological structures for a wide range of biological and medical studies. Xray phasecontrast imaging has experienced rapid development over the last few decades, and in this technology, the phase modulation strategy of. At its current state, its medical use still has to be demonstrated.
Pdf the purpose of this study was to determine the contrast to noise ratio cnr of the xray images taken with the phase contrast imaging. Regularized newton methods for xray phase contrast and general. The classic moire effect is the product of two intensity patterns of slightly different sizes or orientations. Phasecontrast imaging with a compact xray light source. Designing the phase grating for talbotlau phasecontrast. The material properties are inferred from the differences in the number of photons detected at the end of defined paths in the sample. It can be found in a variety of forms in diverse applications including metrology, precision measurements, alignment and imaging 11.
Phasecontrast xray imaging virtually all xrays imaging in a medical or biological context is performed by measuring differences in the attenuation of xrays by the tissues. In this chapter, we introduce a new imaging modality that has the potential to develop into a future medical imaging technology. Conebeam xray phase contrast tomography of biological samples. Phasecontrast xray imaging pci or phasesensitive xray imaging is a general term for different technical methods that use information concerning changes. While traditional xray imaging yields an image that maps a samples absorptive properties by measuring xray photon. Improved reconstruction technique for moire imaging using. A universal moire effect and application in xray phase. Transparent phase masks, or phase gratings, imprint a periodic phase pattern on a wave front.
Information about the attenuation, smallangle scattering and phase. These tutorials introduce some basics of imaging with coherent xrays, focusing on phase contrast. Contribution to phase contrast imaging, reconstruction and. Simulated gratingbased xray phase contrast images of cfrp. The performance of a talbotlau interferometer depends to a great extent on its visibility. Xray phasecontrast imaging xpci overcomes the problem of low contrast between different soft tissues achieved in conventional x. Journal of imaging article improved reconstruction technique for moire imaging using an xray phase contrast talbotlau interferometer maria seifert id, michael gallersdorfer, veronika ludwig id, max schuster id, florian horn id, georg pelzer, jens rieger, thilo michel and gisela anton.