Collection Of theses on high power laser and plasma physics, 2013, 11 (1): 021103, Published Online: Jun. 2, 2017
High-contrast imaging for weakly diffracting specimens in coherent diffraction imaging
110.3010 Image reconstruction techniques 050.1970 Diffractive optics 070.0070 Fourier optics and signal processing
Abstract
Coherent diffraction imaging (CDI) and ptychography techniques bypass the difficulty of having highquality optics in X-ray microscopy by using a numerical reconstruction of the image that is obtained by inverting the diffracted intensity recorded by a charge-coupled device array. However, the reconstruction of the image from the intensity data obtained from a weakly diffracting specimen is known to be difficult because of the obvious reduction in signal-to-noise ratio (SNR). In this case, the specimen only slightly modifies the probe diffraction pattern, resulting in difficulty in the identification of the detailed structure of the specimen from the reconstructed image because of the poor contrast and sharpness of the image. To address this situation, a modification in the image retrieval algorithms used in the iterative reconstruction of the image is suggested. This modification should double the presence of high spatial frequencies in the diffraction pattern to enhance the contrast and edge detection in existing imaging techniques.
Xingchen Pan, Suhas P. Veetil, Cheng Liu, Qiang Lin, Jianqiang Zhu. High-contrast imaging for weakly diffracting specimens in coherent diffraction imaging[J]. Collection Of theses on high power laser and plasma physics, 2013, 11(1): 021103.