The switching time of existing thermocapillarity optical switches is about two orders of magnitude larger than that of other optical switches,such as a thermooptics switch and a free-space switch using microelectromechanical system technology. This paper reports a thermocapillarity switch whose switching time is comparable to that of the thermooptics and free-space switches. The greatly improved switching time is achieved by lowering the absolute viscosity of the refractive-index matching liquid and improving the switch design.
Tomomi Sakata, Hiroyoshi Togo, Mitsuhiro Makihara, Fusao Shimokawa, and Kazumasa Kaneko, "Improvement of Switching Time in a Thermocapillarity Optical Switch," J. Lightwave Technol. 19, 1023- (2001)