Progress in development of a multiple-order diffractive engineered (MODE) lens as applied to space telescopes, where an ultralightweight primary lens is used instead of a mirror, is presented. Precision glass molding is used to fabricate a prototype 0.24 m diameter primary lens, and advanced alignment technology is used to bond lens segments into a ridged, monolithic structure. The primary lens is used in an f/4.17 telescope with a color corrector that provides diffraction-limited imaging over the astronomical R-band of wavelengths (589 nm to 727 nm) and +/- 0.125° field of view. Fabrication data, alignment results, and imaging experiments are presented.
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