The cold neutron reflectometer permits routine measurement of reflectivities as low as 10-6 in typical run times of a few hours. As shown in the schematic drawing below, a pyrolytic graphite monochromator array deflects neutrons onto a horizontal sample surface at a shallow angle ofincidence. Reflected neutrons are measured by a detector after passing through an exit slit system.
Independent movement of both sample and detector allows measurement of off-specular scattering. A position-sensitive detector permits simultaneous measurement of specular and off-specular scattering.