A sensor element (1, 20, 21, 22) capable of sensing more than one spectral band of electromagnetic radiation with the same (x-y) spatial location, especially where the dimensions x-y-z form a set of Cartesian coordinates with z parallel to the direction of incident electromagnetic radiation, is characterized in that the element consists of a stack of sub-elements (3, 5, 7) each capable of sensing different spectral bands of electromagnetic radiation. These sub-elements (3, 5, 7) each contain a non-silicon semiconductor where the non-silicon semiconductor in each sub-element (3, 5, 7) is sensitive to and/or has been sensitized to be sensitive to different spectral bands of electromagnetic radiation.