A supportive substrate (11) carries areas of first and second types (12, 13). The first type (12) comprises layers (15, 16) of differing refractive index (n1, n2) acting as an interference filter. The second type (13) comprise an absorption layer (14) of low reflectivity, on the substrate. An Independent claim is included for the method of manufacture of the device. A first, low refractive index layer is applied to the substrate and structured to differentiate the areas. Over the entire area, a second layer is applied. This has a markedly greater refractive index than the first layer. Preferred features: The reflective substrate is polished steel. The absorbing layer and the uppermost layer (16) of the highly reflective region (12) are comprised of identical materials. Material of the absorbing and reflective layers, has an absorption coefficient k of 0.1-0.5. Layers (15, 16) of the highly-reflective regions have considerably differing refractive index, the first layer (15) being directly on the reflective substrate, and having the smaller refractive index (n1). The second of these layers has a refractive index n2, no less than 2.2. Thickness d2 of the second layer (16) is 30 - 50 nm. Refractive index of the first layer is between 1.3 and 1.7. Thickness of the first layer is 100-150 nm. The highly-reflective region has a dielectric reflection-interference filter construction. PVD (plasma vapor deposition) is employed for overall coating, photolithography being employed for structuring. The second layer is produced by PVD. In a first stage, the substrate is completely coated with a photo-lacquer. This is structured, leaving regions with and without this coating. To structure the first layer after lacquering, regions are removed where photo-lacquer and the first layer coexist.
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