Fabrication of a Fabry-Pérot dielectric filter with sub-nanometer narrow bandwidth

Abstract

The dielectric filter is a commonly used optical filter, benefiting from its low production cost and compact size. While the bandwidth of the dielectric filters made by traditional fabrication technique can hardly reach sub-nanometer. Here, we present a method for fabricating a sub-nanometer dielectric filter using the Fabry-Pérot (FP) cavity. This FP dielectric filter features a full width at half maximum (FWHM) bandwidth of ~0.18 nm, a free spectral range (FSR) of 11.23 nm and a peak transmittance of over 80%.