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Highly-transparent coverglasses coated with broadband and omnidirectional antireflective (AR) moth-eye nanopatterned ultra-violet (UV) curable polymer, i.e., Norland Optical Adhesive (NOA) 63, films are reported. The moth-eye nanopatterns on the NOA63 polymer films/glasses are transferred from the silicon molds with conical nanogratings (NGs) using poly-dimethylsiloxane stamps by a soft imprint lithography technique. For the NOA63 NGs/glasses, surface wetting behaviors, UV radiation/thermal effects, and optical properties, together with theoretical analyses using rigorous coupled-wave analysis calculations, are investigated. For a period of 380 nm, the NOA63 NGs/glass exhibits a hydrophobic surface with a water contact angle of ~112°. Furthermore, it increases the transmittance of the bare glass over a wide range of wavelengths and incident light angles, showing the higher solar weighted transmittance ( T SW ) of ~93.2% at an incident angle ( θ i ) of 0° and the larger average T SW value of ~83.6% at θ i =10–70° than those (i.e., T SW ~90.1% at θ i =0° and average T SW value of ~81.5% at θ i =10–70°) of the bare glass in the wavelength range of 350–1800 nm. In addition, it shows a relatively good stability under intense UV radiation and high temperature. By employing the 380 nm-period NG patterned NOA63 films into an AR coating of coverglasses in encapsulated III-V GaInP/GaInAs/Ge triple-junction solar photovoltaic (PV) sub-receiver modules, an enhanced power conversion efficiency (PCE) of 31.33% is obtained mainly due to an increased short-circuit current density ( J SC ) of 14.68 mA/cm 2 compared to reference PV modules with the bare coverglass (i.e., PCE=30.12% and J SC =14.07 mA/cm 2 ) at θ i =0°. For incident angle-dependent PV module characteristics, it also has more outstanding solar energy conversion properties in a wide θ i range of 10–70°. [ABSTRACT FROM AUTHOR]