Abstract: The present invention is directed to a light gathering lens that instantaneously corrects for the effect of varying distance between an object and a sensor such as a range finding sensor or LiDAR. Methods of designing these lenses using both traditional lenses and exotic metamaterials and gradient index materials are disclosed, as well as methods of optimizing a design for a given detector type and application. Range-finding systems using these lenses in practice to optically correct for radiometric variation of returned signals received from an object of varying distances are further disclosed. Lenses and range-finding systems suitable for use in a variety of electromagnetic wavelength ranges are disclosed including but not limited to visible, infrared, and millimeter wave regimes.