Electrowetting-actuated optofluidic phase modulator

In this paper, an optofluidic phase modulator based on electrowetting is presented. The modulator consists of an inner and outer chamber. Two immiscible liquids are filled into the chambers, and a transparent sheet is fixed between the liquid-liquid interface to obtain a flat interface. By applying different voltages to the modulator, the flat interface moves up and down leading to the change of optical path length. Consequently, the variation of the optical path in the proposed modulator exploits the ability to alter the optical phase. To prove the concept, a prototype of the phase modulator is fabricated in experiment, and the ability of phase modulation is detected. Our proposed modulator performs optical phase shift up to similar to 6.68 pi driven with 150 V. Widespread applications of such an optofluidic phase modulator is foreseeable. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

An optofluidic phase modulator based on electrowetting is proposed in this paper, utilizing the movement of a flat interface between two immiscible liquids to change the optical path length and achieve optical phase modulation. A prototype of the modulator is fabricated in experiment to demonstrate its capability of phase modulation, with the potential for achieving optical phase shift up to 6.68π when driven with 150 V. The widespread applications of such a modulator are foreseeable.