An imaging-plate detector for small-angle neutron scattering

Small-angle neutron scattering (SANS) measurements have been performed on l ong-flight-path pinhole-collimation SANS instruments using, as a two-dimens ional position-sensitive detector, both a neutron imaging plate, incorporat ing gadolinium, and a two-step transfer method, with dysprosium foil as the image transfer medium. The measurements are compared with corresponding da ta taken using conventional position-sensitive gas proportional counters on the SANS instruments in order to assess the viability of the imaging techn iques. The imaging plates have pixel sizes of about two orders of magnitude smaller than those of the gas proportional counter. The reduced pixel size provides definite advantages over the gas counter in certain specific situ ations, namely when limited space necessitates a short sample-to-detector d istance, when only small samples (comparable in size to the detector pixels ) are available, or when used in conjunction with focusing beam optics.