Optoelectrowetting

This technique builds on the principle of electrowetting, which has proven useful in liquid actuation due to fast switching response times and low power consumption.

Where traditional electrowetting runs into challenges, however, such as in the simultaneous manipulation of multiple droplets, OEW presents a lucrative alternative that is both simpler and cheaper to produce.

OEW surfaces are easy to fabricate, since they require no lithography, and have real-time, reconfigurable, large-scale manipulation control, due to its reaction to light intensity.

The droplet is placed on an insulating substrate located in between an electrode.cooxoxc9x The optoelectrowetting mechanism adds a photoconductor underneath the conventional electrowetting circuit, with an AC power source attached.

This mechanism provides a solution to the size limitation of physical pixilated electrodes by utilizing dynamic and reconfigurable optical patterns and enables operations such as continuous transport, splitting, merging, and mixing of droplets.

[6] The photo-sensitive electrowetting is achieved via optical modulation of carriers in the space charge region at the insulator-semiconductor junction which acts as a photodiode – similar to a charge-coupled device based on a metal–oxide–semiconductor structure.

[7] Conventional microfluidic systems aren't easily adaptable to handle different compounds, requiring reconfiguration that often results in the device being impractical as a whole.