Polycapillary x-ray optics for macromolecular crystallography

Polycapillary x-ray optics have found potential application in many different fields, including antiscatter and magnification in mammography, radiography, x-ray fluorescence, x-ray lithography, and x-ray diffraction techniques. In x-ray diffraction, an optic is used to collect divergent x-rays from a point source and redirect them into a quasi-parallel, or slightly focused beam. Monolithic polycapillary optics have been developed recently for macromolecular crystallography and have already shown considerable gains in diffracted beam intensity over pinhole collimation. Development is being pursued through a series of simulations and prototype optics. Many improvements have been made over the stage I prototype reported previously, which include better control over the manufacturing process, reducing the diameter of the output beam, and addition of a slight focusing at the output of the optic to further increase x-ray flux at the sample. We report the characteristics and performance of the stage I and stage II optics.