Theoretical and Experimental Characterisations of Optofluidic Lenses with Subunit Horizontal-to-Vertical Aspect Ratios

Abstract

Optofluidic systems are a subset of microfluidics and are used in a variety of applications that require reconfigurable optics, such as detection systems, biochemical applications, spectrometry, and in-plane light focusing. Elliptical optofluidic lenses can provide tunable optical parameters in different optical planes. This tunability is achieved through modifications to the aspect ratio (AR). In this thesis, we present an optofluidic lens with a subunit AR, starting with the theory behind the working of this system, to simulation and finally analysis of the experimental results. In the theoretical analysis, improved tunability of focal length, longitudinal spherical aberration, and beam cone angle is observed in the subunit AR regime compared to the superunit AR regime. In the experimental analysis, the shape of the microdroplet is altered, and a ten percent reduction in AR on applying a high voltage across the microdroplet is observed. We ultimately test and characterise the optofluidic lens in an imaging application.