Abstract. The designs of two imaging freeform systems using nonuniform rational basis-spline (NURBS) optical surfaces are described. The first system, a 10 deg ×9 deg f ∕2 three-mirror anastigmat has four times higher spatial resolution over the image plane compared with the equivalent conventional rotational aspheric design, and 2.5 times higher resolution compared with a 10th-order X Y polynomial freeform design. The mirrors for the NURBS freeform design have more than twice the asphericity than the conventional rotational and X Y polynomial designs. In the second system, a Ritchey-Chretien telescope followed by a two-mirror NURBS freeform corrector is compared to a four-mirror Korsch telescope, for imaging to a visible-infrared imaging spectrometer. The freeform corrector design had 70% smaller spot sizes over the field and eliminated the large tertiary required in Korsch type design. Both of these NURBS freeform designs are possible due to a custom optical design code for fast accurate NURBS optimization, which now has parallel raytracing for thousands of NURBS grid points.

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Deployable, large aperture space optics require precision phasing of segmented and uniquesparsely-filled primaries for optical alignment which introduce challenges to these already complex optomechanical designs. This work presents a multifunctional high strain composite hinge with integrated piezoelectric actuation capabilities to support deployable space telescopes and address these challenges. Finite element simulations and experimental testing are utilized to design and validate the multifunctional high strain composite hinge. Macro Fiber Composite actuators are integrated with the high strain composite hinge in a specific layout based on the finite element analyses to induce piston, pitch, and roll tip motions for precision optical alignment after deployment. A feedback control system is implemented to demonstrate an actuation resolution of better than 25 nm over a 15 µm range for a single degree of freedom, validating the multifunctional high strain composite hinge for alignment to levels required for visible wavelength optical systems.