A non-imaging optical energy transfer system includes a tapered light pipe and associated field lens as its central energy transfer mechanism. The light pipe/lens combination is located between two separate sections of the sys-tem which individually have the same throughput or etendue but otherwise differ in f/#, beam focus, and pupil sizes. The transfer system is disclosed used in combination with a circular variable filter-absorption cell infrared spectrometer and an internal reflection spectrometer, employing a multiple internal reflection crystal.
NON-IMAGING OPTICAL ENERGY TRANSFER SYSTEM