A sensor device comprising: a plurality of sensor elements; and a plurality of optical filters disposed over the the plurality of sensor elements, wherein each of the optical filters includes: a plurality of dielectric layers; and a plurality of silver or silver alloy metal layers stacked in alternation with the plurality of dielectric layers, wherein each of the plurality of metal layers is substantially uniform in thickness throughout a central portion of the optical filter, and tapers off in thickness at a periphery of the optical filter to has a tapered edge, at the periphery of the optical filter (200,), that is protectively covered by one or more of the plurality of dielectric layers, and each of the plurality of metal layers is separated from a substrate of an optical filter, of the one or more optical filters, using at least one the plurality of dielectric layers, and each of the plurality of metal layers is encapsulated by two nearest of the plurality of dielectric layers; and wherein each of the one or more optical filters further includes a plurality of corrosion-suppressing layers disposed between the plurality of dielectric layers and the plurality of metal layers, and the metal layers are encapsulated by the corrosion-suppressing layers, characterised in that the plurality of sensor elements are disposed in a two-dimensional array, and the plurality of optical filters are disposed in a corresponding two-dimensional array, and the plurality of optical filters includes different types of optical filters having different passbands from one another. a plurality of sensor elements; and a plurality of optical filters disposed over the the plurality of sensor elements, wherein each of the optical filters includes: a plurality of dielectric layers; and a plurality of silver or silver alloy metal layers stacked in alternation with the plurality of dielectric layers, wherein each of the plurality of metal layers is substantially uniform in thickness throughout a central portion of the optical filter, and tapers off in thickness at a periphery of the optical filter to has a tapered edge, at the periphery of the optical filter (200,), that is protectively covered by one or more of the plurality of dielectric layers, and each of the plurality of metal layers is separated from a substrate of an optical filter, of the one or more optical filters, using at least one the plurality of dielectric layers, and each of the plurality of metal layers is encapsulated by two nearest of the plurality of dielectric layers; and a plurality of dielectric layers; and a plurality of silver or silver alloy metal layers stacked in alternation with the plurality of dielectric layers, wherein each of the plurality of metal layers is substantially uniform in thickness throughout a central portion of the optical filter, and tapers off in thickness at a periphery of the optical filter to has a tapered edge, at the periphery of the optical filter (200,), that is protectively covered by one or more of the plurality of dielectric layers, and each of the plurality of metal layers is separated from a substrate of an optical filter, of the one or more optical filters, using at least one the plurality of dielectric layers, and each of the plurality of metal layers is encapsulated by two nearest of the plurality of dielectric layers; and