title: Light induced fluidic waveguide coupling.
abstract: We report on the development of an opto-fluidic waveguide coupling mechanism for planar solar concentration. This mechanism is self-adaptive and light-responsive to efficiently maintain waveguide coupling and concentration independent of incoming light's direction. Vapor bubbles are generated inside a planar, liquid waveguide using infrared light on an infrared absorbing glass. Visible light focused onto the bubble is then reflected by total internal reflection (TIR) at the liquid-gas interface and coupled into the waveguide. Vapor bubbles inside the liquid are trapped by a thermal effect and are shown to self-track the location of the infrared focus. Experimentally we show an optical to optical waveguide coupling efficiency of 40% using laser light through a single commercial lens. Optical simulations indicate that coupling efficiency > 90% is possible with custom optics.
authors.affiliation: École Polytechnique Fédérale de Lausanne, Laboratory of Applied Photonics Devices, CH-1015 Lausanne, Switzerland. volker.zagolla@epfl.ch
authors.forename: Volker
authors.initials: V
authors.lastname: Zagolla
authors.forename: Eric
authors.initials: E
authors.lastname: Tremblay
authors.forename: Christophe
authors.initials: C
authors.lastname: Moser