Because light sources and detectors exhibit significant spectral variations, the detector response in an optical system can generally be found only by means of a tedious numerical integration process. The evaluation of the MTF in polychromatic light requires an even more extensive numerical procedure. Here, integration results are presented for all combinations of six commonly used light sources and twelve common detectors. The MTF's for perfect lenses and efficiency factors are presented.
Leo Levi, "Detector Response and Perfect-Lens-MTF in Polychromatic Light," Appl. Opt. 8, 607-616 (1969)