  The design and characteristics of a double supermirror monochromator for
neutron instrumentation at the Laboratoire Leon Brillouin is described. The aim
of this monochromator is to reduce the intense gamma-radiation produced by
conventional velocity selectors and to avoid a direct view of the guide while
keeping a comparable neutron transmission (higher than 70%). The monochromator
offers a continuous choice of wavelength selection in the range 0.5 to 2 nm.
