For solar lighting systems employing fiber optic waveguides1,2, to conduct the collected light, paraboloidal mirrors are the preferred reflector choice. To achieve optimum performance in systems with relatively small collection apertures, both the quality of the mirror and the quality of optical system alignment must be well controlled. In systems employing multiple waveguides with a single paraboloid, the focus of the paraboloid must be segmented into several separate focal points directed into individual fibers. Each waveguide entrance aperture must be accurately co-located with its designated focal point so that the image that is formed on the fiber will have the fewest possible aberrations and thus, the smallest possible focused spot size. Two methods for aligning individual optical waveguides in a multi-aperture paraboloidal collection system are described. The first method employs a commercially available collimation tester to incrementally improve the alignment. The second, a deterministic method, employs a cube corner retro-reflector and an easily constructed imaging system to reliably align the fibers to their respective segments of the parent paraboloid. The image of the focused spot formed by the light that is returned from the retro-reflector reveals alignment information that is easily interpreted to enable pitch, yaw and focus errors to be systematically removed. This ensures that the alignment of the system is optimized to reduce aberrations prior to final adjustment of the system “on-sun”.

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