Development of a compound focusing lens: improvement of signal–noise ratio

Abstract We proposed a method to improve signal–noise ratio of the Fresnel-type neutron lens. The Gd mask of concentric circle thin layer reduced 80% noise, at the best, due to the Fresnel-type lens shape. As the transmission for 1.1 nm neutrons decreased from 0.83 to 0.79 by using the Gd mask, the loss was 0.04.