METHOD FOR MANUFACTURING A MULTI-SPECTRAL FILTER AND MULTI-SPECTRAL FILTER THUS MANUFACTURED

The present invention relates to a method for manufacturing a multi-spectral filter comprising a plurality of filtering elements, each filtering element being adapted to transmit a spectral electromagnetic radiation band from among a plurality of spectral bands, characterised in that the method comprises the following steps: - depositing a first common reflector for the plurality of filtering elements onto a substrate; - depositing, onto the first reflector, a first cavity stack comprising at least N cavity layers and N-1 barrier layers deposited in an alternating manner, the upper layer being a cavity layer; - selectively etching a number M of cavity layers in a plurality of zones each corresponding to a filtering element, where M varies from 0 to N-1 from one zone to the next; and - selectively etching barrier layers located between the etched cavity layers, and so that each filtering element comprises N-M cavity layers and N-M-1 non-etched barrier layers, and in that the cavity layers and the barrier layers are produced from different and optically transparent materials.