1. A detector device comprising an x-ray detector structure having a detection surface defining at least one separately addressable region for detecting incident x-ray radiation intensity thereon, wherein the separately addressable region is divided into a plurality of sub-regions provided on spaced across the detection surface of the separately addressable region, each sub-region provided with a filter layer on the detection surface, the filter layers of each sub-region of a given separately addressable region comprising discrete and different materials with discrete defined and spectroscopically spaced x-ray absorption edges.