OPTICAL FILTER SUITABLE FOR DEALING WITH A RADIATION OF VARIABLE INCIDENCE AND DETECTOR INCLUDING SAID FILTER

摘要

An optical filter for filtering an electromagnetic radiation of variable angle of incidence, includes a stack of at least one dielectric or semi-conductor layer arranged between two partially reflective layers, said stack defining a set of Fabry-Pérot cavities set to a predetermined wavelength. The average refractive index of the dielectric or semi-conductor layer is variable in a plane orthogonal to the direction of the stack so as to compensate the effects of the variation in the angle of incidence of the electromagnetic radiation on the transmission spectrum of the cavities.