Variable filters, in which the bandpass central wavelength shifts along a dimension of the component, is a promising way to simplify and to miniaturize imaging spectrophotometer systems for spatial observation. In this paper, we present a new method for the fabrication of variable filters with different spatial profiles based on plasma assisted reactive magnetron sputtering. Variable filters are based on the variation of the thickness of the layers deposited on the substrate. The layers are manufactured using a Bühler HELIOS machine. To insure a non-uniformity of the deposited layers, adapted masks are placed in front of the targets for the low and high refractive index materials. The uniformity of these layers is measured via a homemade set-up allowing a local measurement of the transmission over the component surface. We demonstrate the fabrication of a narrow variable filter where all the thicknesses of all layers are changing, resulting in an overall shift of the filter.
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