Studies On The EWOD Features And The Electric Field Distribution Of Variable Focus Liquid Lens.

Micro-fluidic liquid zoom lens based on EWOD is easy to realize the miniaturization andarray scale, widely used in the field of optical communications, digital product, bio-medicaltesting. The main subject is to realize the numerical simulation and analysis of the characteristicsof EWOD and of the electric field distribution of the inner core structure. This paper firstintroduces the development of micro-fluidic technology and dielectric wetting, followed byexperimental results to analyze the characteristics of the dielectric (EWOD) with conductivesilicon rubber. Because of small size (millimeters) of liquid zoom lens, artificial measurement ofthe electric field is more difficult. So we use COMSOL software to establish the appropriatemodel to make a concrete analysis of the internal electric field distribution, mainly to study theelectric field distribution on the sidewall of the liquid lens insulating layer. Specific activities areincluded as the following:(1) Verify the EWOD characteristics of the conductive silicon rubber chip. Collect the dropletimages with different voltages on the conductive silicon rubber, using the image processingfunctions of MATLAB software to extract the droplet boundary and calculate the contact angle ofdroplets; by least squares to fit the relationship curve between contact angle and voltage to verifythe EWOD characteristics.(2) Establish the appropriate model by using the COMSOL software (multi-physics analysissoftware), changing angle of the core structure, the voltage, and radius parameters to observe theelectric field distribution in the inner core.