Abstract: An active illumination apparatus includes an emission source configured to illuminate a field of view. The emission source includes one or more emitter elements, and is configured to output optical signals having respective wavelengths that vary based on respective portions of the field of view to be illuminated thereby. The respective wavelengths of the optical signals may vary over respective field angles of the field of view according to variations in optical characteristics of a detection module, such as a passband of a detector-side spectral filter element, for the respective field angles. Related imaging apparatus and methods are also discussed.