Work

Fabrication and Characterization of Flexible Electrowetting on Dielectrics (EWOD) Microlens

Year: 2014

Type: article

Abstract: We present a flexible variable-focus converging microlens actuated by electrowetting on dielectric (EWOD). The microlens is made of two immiscible liquids and a soft polymer, polydimethylsiloxane (PDMS). Parylene intermediate layer is used to produce robust flexible electrode on PDMS. A low-temperature PDMS-compatible fabrication process has been developed to reduce the stress on the lens structure. The lens has been demonstrated to be able to conform to curved surfaces smoothly. The focal length of the microlens is 29-38 mm on a flat surface, and 31-41 mm on a curved surface, varying with the voltage applied. The resolving power of the microlens is 25.39 line pairs per mm by a 1951 United States Air Force (USAF) resolution chart and the lens aberrations are measured by a Shack-Hartmann wavefront sensor. The focal length behavior on a curved surface is discussed and for the current lens demonstrated the focal length is slightly longer on the curved surface as a result of the effect of the curved PDMS substrate.

Source: Micromachines

DOI: 10.3390/mi5030432

Authors: Chenhui Li, Hongrui Jiang

Institution: University of Wisconsin–Madison

Language: English

Topic: Electrowetting and Microfluidic Technologies

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,534

Funder: National Institutes of Health