We report broadband and quasi-omnidirectional antireflective (AR) structures inspired to the nipple arrays of moth eyes. These nanocoatings, based on thin elastomeric films, are prepared by simple self-assembly processing of a co-polymer specifically designed to this purpose, and PDMS replica molding. Typically, their surface is covered by a compact distribution of hemispherical nanodomes of about 250 nm in diameter and about 100 nm in height. When these novel nanostructures are applied on a single glass surface, a maximum of 2% transmission enhancement (equivalent to a 50% reduction of the reflected component) towards wavelengths ranging from visible to near IR region is obtained. A considerable AR power is observed also at a wide range of incident angles ranging from normal to 50°. These properties could be attributed to an optimized graded refractive index profile resulting from the randomly distributed and close-packed nanodomes. Moreover, thanks to their elastomeric nature, these crack-free films can be easily applied on glass, as stickers, and periodically replaced, thus offering the possibility of easy dirt removal from an optical device.

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We report our recent results on the fabrication of nanostructured polymer layers aimed at developing efficient antireflection coating on silicon. The proposed manufacturing approach is based on self-assembly and relies on breath figure formation. By simple and straightforward operations, we are able to produce different nanostructured coatings: densely packed nanodomes, randomly distributed nanopores, and multilayered close-packed nanopores. By optical reflectivity measurements on coated silicon wafers, we show that the latter type of nanostructure is able to reduce the reflectivity of standard silicon surface (≈40% at 450 nm) to about 10%.

This paper describes the laser transmitter assembly used in the ALADIN instrument currently in C/D development phase for the ESA ADM-AEOLUS mission (EADS Astrium as prime contractor for the satellite and the instrument). The Laser Transmitter Assembly (TXA), based on a diode pumped tripled Nd:YAG laser, is used to generate tunable laser pulses of 150 mJ at a nominal wavelength of 355 nm. This laser is operated in burst mode, with a pulse repetition cycle of 100 Hz. The TXA is composed of the following units: a diodepumped CW Nd:YAG Laser named Reference Laser Head (RLH), used to inject a diode-pumped, Q-switched, amplified and frequency tripled Nd:YAG Laser working in the third harmonic referred as Power Laser Head (PLH) and a Transmitter Laser Electronics (TLE) containing all the control and power electronics needed for PLH and RLH operation. The TXA is made by an European consortium under the leadership of Galileo Avionica (It), and including CESI (It), Quantel (Fr), TESAT (Ge) and Thales (Fr).

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