Optofluidic laser scanner based on a rotating liquid prism

We demonstrate an electrowetting-actuated optofluidic system based on a rotatable liquid prism implemented as a two-dimensional laser scanner. The system is fabricated through a novel technology using a patterned flexible polymeric foil on which a high density of electrodes is structured and which is subsequently inserted into a cylindrical housing. The resulting radial electrode array is used for electrowetting actuation of two fluids filled into the cylinder, which allows a controllable tilt and orientation of the planar liquid interface and thus represents a tunable rotating prism. Finite element simulations and subsequent experimental verification show that this highly planar and precisely positionable liquid/liquid interface may be actuated to a deflection angle of +/- 6.4 degrees, with a standard deviation of +/- 0.18 degrees, and rotated 360 degrees about the vertical axis. Power consumption is limited to several microwatts, and switching times of several hundred milliseconds were determined. (C) 2016 Optical Society of America