Journal article
Fabrication of Large Area Broadband and Omnidirectional Antireflective Transparent Foils by Roll-to-Roll Extrusion Coating
Department of Mechanical Engineering, Technical University of Denmark1
Department of Micro- and Nanotechnology, Technical University of Denmark2
Polymer Micro & Nano Engineering, Department of Micro- and Nanotechnology, Technical University of Denmark3
DFM - Dansk Fundamental Metrologi A/S4
Department of Photonics Engineering, Technical University of Denmark5
Optical Microsensors and Micromaterials, Department of Photonics Engineering, Technical University of Denmark6
Heliac ApS7
This study investigates the fabrication and performance of broadband and omnidirectional antireflective polymer foils, in the visible spectrum (400–800 nm), consisting of subwavelength inverted moth-eye structures. The foils are fabricated by a high throughput roll-to-roll extrusion coating process allowing structuring on both sides at a rate of 60 m min−1, with web width 45 cm.
The highest average transmittance obtained in the visible spectrum is (98 ± 1) %; compared with (92 ± 1) % for the unstructured foil. The antireflective foil shows no significant difference in transmittance between normal incidence and incidence up to at least 60°. The foil performance is also investigated for different depths (Dp) and shapes of structures.
The transmittance initially increases with Dp and reaches a maximum at Dp ≈ 120 nm. For process parameters yielding greater depths, other shape factors also play a critical role in the foil's antireflective properties.
Language: | English |
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Year: | 2017 |
Pages: | 1700027 |
ISSN: | 14392054 and 14387492 |
Types: | Journal article |
DOI: | 10.1002/mame.201700027 |
ORCIDs: | Lotz, Mikkel Rønne , Pedersen, Henrik Chresten , Taboryski, Rafael J. and 0000-0001-8766-6638 |