Abstract: A fiber optic illumination system includes a light source, a waveguide, a primary optical fiber, a diffraction grating wavelength selector, and a secondary optical fiber. One or more lamps and/or solid-state devices may be employed as the light source. The waveguide includes a straight collecting segment, a tapered condensing segment, and a straight homogenizing segment, may be fabricated from fused silica as a single monolithic component, conveys light from the light source to the primary optical fiber by transmission and/or internal reflection, and may be provided with UV and/or IR blocking filter coating(s). The primary optical fiber may be colorless or fluorescent optical fiber. Light transmitted by the primary optical fiber may be divided into its constituent wavelength components by the diffraction grating, and a desired wavelength component may be received by, transmitted by, and emitted from the secondary optical fiber.