Three-cavity multichannel optical spectrum step type integrated optical filter

The invention discloses a spectrum step type integrated filter with three cavities and multiple channels. By using a method of changing the optical thickness of a micro-domain in a spacer-layer, the spectrum step type integrated filter of the invention adopts three-cavity structure, combines vacuum plating technology and semi-conductor ion beam etching process and realizes the integration of a bandpass filter with multiple channels in the same substrate. The integrated filter can be widely used for the dense obtaining of multi-spectrum (high spectrum) of aeronautic and astronautic remote sensing instruments. The tiny spectrum step type integrated filter with multiple channels has the advantages that the channels have good spectral rectangle degree and high light splitting efficiency; the combined etching process is adopted, thus greatly promoting the rate of finished products in comparison with the traditional filter integrated in sequence; multiple spectral channels can be formed in a micro-domain, thus being capable of realizing the correct positioning of spatial location and spectral position and being easy to realize high spectrum.