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Randomly distributed anti-reflective nanostructures were fabricated on both surfaces of cylindrical lenses and freeform optical elements using a plasma-assisted reactive-ion etching technique. An average spectral transmission of 98% was measured across the wavelength range from 340 to 800 nm. Mid-band full-angle directional scatter measurements show a difference of six orders of magnitude in transmission intensity between specular and off-specular angles. Measurements before and after the etching process show little to no wavefront distortion for the cylindrical lenses. The enhanced transmission optics were used as part of the dual-unit arrayed wide-field astronomical camera system tested on the Harlan J. Smith telescope at the McDonald Observatory, and their performance was contrasted with conventional thin film coated component performance. 

Diffractive optics are structured optical surfaces that manipulate light based on the principles of interference and diffraction. By carefully designing the diffractive optical elements, the amplitude, phase, direction, and polarization of the transmitted and reflected light can be controlled. It is well-known that the propagation of light through diffractive optics is sensitive to changes in their structural parameters. In this study, a numerical analysis is conducted to evaluate the capabilities of slanted-wire diffraction gratings to function opto-mechanically in the infrared spectral range. The slanted wire array is designed such that it is compatible with fabrication by two-photon polymerization, a direct laser-writing approach. The modeled optical and mechanical capabilities of the diffraction grating are presented. The numerical results demonstrate a high sensitivity of the diffracted light to changes in the slant angle of the wires. The compressive force by which desired slant angles may be achieved as a function of the number of wires in the grating is investigated. The ability to fabricate the presented design using two-photon polymerization is supported by the development of a prototype. The results of this study suggest that slanted-wire gratings fabricated using two-photon polymerization may be effective in applications such as tunable beam splitting and micro-mechanical sensing.