Open AccessModeling the surface of fast-cured polymer droplet lenses for precision fabrication
Author(s) -
Y. S. Sung,
Jacob Garan,
Zhenyu Hu,
Xiaonan Shan,
Wei-Chuan Shih
Publication year - 2018
Publication title -
applied optics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.668
H-Index - 197
eISSN - 2155-3165
pISSN - 1559-128X
DOI - 10.1364/ao.57.010342
Subject(s) - surface tension , polydimethylsiloxane , materials science , viscosity , polymer , optics , fabrication , molding (decorative) , nanotechnology , composite material , thermodynamics , physics , medicine , alternative medicine , pathology
Optical lenses with diameter in the millimeter range have found important commercial use in smartphone cameras. Although these lenses are typically made by molding, recent demonstration of fast-cured polymer droplets by inkjet printing has gained interest for cost-effective smartphone microscopy. In this technique, the surface of a fast-cured polydimethylsiloxane droplet obtains dynamic equilibrium via the interplay of surface tension, gravity, thermalization, and a steep viscosity hike. The nature of surface formation involves multiple physical and chemical domains, which represent significant challenges in modeling with the Young-Laplace theory, assuming constant surface tension and viscosity. To overcome these challenges, we introduce the concept of effective surface tension, which allows fast-cured polymer droplets to be modeled as normal liquid droplets with constant viscosity.