Remodeling of the optics for a micro-focusing protein crystallography beamline at SPring-8

Micro-focusing protein crystallography beamline BL45XU was remodeled using focusing mirrors and a slit as a secondary source. In the horizontal direction, two stage focusing was adopted and beam size was controlled by the slit and defocusing of 2nd mirror by changing the glancing angle. In the vertical direction, beam size was enlarged by defocusing by changing the glancing angle. Beam profile and photon flux through slit and mirror were estimated using a wave calculation, and compared with the measurements. We verified that beam size can be controlled using a slit and mirror defocusing from 5×5 to 50×50 μm2, and measured photon flux agreed with estimation.