US Patent 11936845 Localized window contaminant detection

The present disclosure relates to contaminant detection systems and related optical systems and methods. An example contaminant detection system includes an optical coupler configured to couple light into and/or out of an optical element. The contaminant detection system also includes a plurality of light-emitter devices configured to emit emission light toward the optical coupler. The contaminant detection system additionally includes a plurality of detector devices configured to detect at least a portion of the emission light by way of the optical element and the optical coupler. The plurality of detector devices is also configured to provide detector signals indicative of a presence of a contaminant on the optical element.