Open AccessDevelopment of large diameter nanostructured GRIN microlenses enhanced with temperature-controlled diffusion
Author(s) -
Adam Filipkowski,
Hoa Thi Nguyen,
Rafał Kasztelanic,
Tomasz Stefaniuk,
Jarosław Cimek,
Dariusz Pysz,
Ryszard Stępień,
K. Krzyżak,
Pentti Karioja,
Ryszard Buczyński
Publication year - 2019
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.27.035052
Subject(s) - microlens , materials science , rod , optics , refractive index , nanorod , lens (geology) , diffusion , optical fiber , fabrication , focal length , wavelength , refractive index profile , fiber , gradient index optics , photon diffusion , optoelectronics , nanotechnology , composite material , medicine , physics , alternative medicine , pathology , layer (electronics) , thermodynamics
Nanostructured GRIN components are optical elements which can have an arbitrary refractive index profile while retaining flat-parallel entry and exit facets. A method of their fabrication requires assembly of large quantities of glass rods in order to satisfy subwavelength requirement of the effective medium theory. In this paper, we present a development of gradient index microlenses using a combination of methods: nanostructurization of the preform and controlled diffusion process during lens drawing on a fiber drawing tower. Adding a diffusion process allows us to overcome limits of the effective medium theory related to maximum size of nanorods in the lens structure. We show that nanorods are dissolved during the fiber drawing process in high temperature and glass components are locally quasi-uniformly distributed. To demonstrate feasibility of the proposed approach, we have developed and experimentally verified the performance of a nGRIN microlens with a diameter of 115 µm composed of 115 rods on the diagonal, and length of 200 µm devoted to work for the wavelength over 658 nm.