Abstract: An infrared radiation filter lens for aircraft lights is comprised of a heat-conductive filter frame disposed in heat-exchange relationship with an aircraft frame and/or its skin to dissipate heat in the filter frame to the aircraft body and the ambient; first and second window panels secured peripherally about longitudinal and transverse side edges by the filter frame in laterally spaced, generally conforming relationship defining a fluid cell therebetween; a fluid, infrared radiation filtration medium disposed for convective circulation within the fluid cell; and baffle members inwardly proximate the transverse side edges of the cell for deflecting convective circulation of the fluid along those sides of the frame. A method for infrared radiation filtration of aircraft lights is also disclosed herein.