Open AccessMicrostructured gradient-index antireflective coating fabricated on a fiber tip with direct laser writing
Author(s) -
Maciej Kowalczyk,
Jakub Haberko,
Piotr Wasylczyk
Publication year - 2014
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.22.012545
Subject(s) - anti reflective coating , materials science , optics , fresnel equations , coating , refractive index , fabrication , wavelength , optical fiber , laser , optoelectronics , composite material , medicine , physics , alternative medicine , pathology
We present a simple broadband gradient-index antireflective coating, fabricated directly on a single mode telecom fiber tip. A regular array of hemi-ellipsoidal protrusions significantly reduce the Fresnel reflection from the glass-air interface. The parameters of the structure were optimized with numerical simulation for the best performance at and around 1550 nm and the coating was fabricated with Direct Laser Writing. The measured reflectance decreased by a factor of 30 at 1550 nm and was below 0.28% for the 100 nm spectral band around the central wavelength. Compared to quarter wavelength antireflective coatings the demonstrated approach offers significantly reduced technological challenges, in particular processing of a single optical material with low sensitivity to imperfections in the fabrication process.