Open AccessA double-sided grating coupler for thin light guides
Author(s) -
Samuli Siitonen,
Pasi Laakkonen,
Jani Tervo,
Markku Kuittinen
Publication year - 2007
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.15.002008
Subject(s) - optics , grating , collimated light , materials science , beam splitter , perpendicular , diffraction grating , light beam , foil method , blazed grating , beam (structure) , optoelectronics , physics , laser , geometry , mathematics , composite material
A simple and efficient solution for coupling a collimated light beam into a thin light guide is presented. The approach is based on two gratings, with their grating lines perpendicular to each other, fabricated into the opposite surfaces of the light guide. The presented numerical simulation shows that an optimized double-sided solution for unpolarized light enables around 2-7 times higher incoupling efficiencies than what is possible with conventional solution based on only one grating. Experimental verification is made by using UV-replicated binary gratings on both sides of a PMMA foil.