As a scanning version of coherent diffraction imaging (CDI), X-ray ptychography has become a popular and verysuccessful method for high-resolution quantitative imaging of extended specimens. The requirements of mostlycoherent illumination and the scanning mechanism limit the throughput of ptychographic imaging. In this paper,we will introduce the methods we use at the Advanced Photon Source (APS) to achieve high-throughputptychography by optimizing the parameters of the illumination beam. One technique we developed is increasingthe illumination ux by using a double-multilayer monochromator (DMM) optics with about 0.8% bandwidth.Compared with our double-crystal monochromator (DCM) optics with 0.01% bandwidth,this DMM optics providesaround 20 times more ux. A multi-wavelength reconstruction method has been implemented to deal withthe resulting degraded temporal coherence from such an illumination to ensure high-quality reconstruction. Inthe other work, we adopt a novel use of at-top focusing optics to generate a at-top beam with the diameterof about 1.5 μm on the focal plane. The better uniformity of the probe and the large beam size allow one tosignificantly increase the step size in ptychography scans and thereby the imaging efficiency.
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