Optofluidics offers new functionalities that can be useful for a large range of applications. What microfluidics can bring
to microphotonics is the ability to tune and reconfigure ultra-compact optical devices. This flexibility is essentially
provided by three characteristics of fluids that are scalable at the micron-scale: fluid mobility, large ranges of index
modulation, and adaptable interfaces. Several examples of optofluidic devices are presented to illustrate the achievement
of new functionalities onto (semi)planar and compact platforms. First, we report an ultra-compact and tunable
interferometer that exploits a sharp and mobile air/water interface. We describe then a novel class of optically controlled
switches and routers that rely on the actuation of optically trapped lens microspheres within fluid environment. A tunable
optical switch device can alternatively be built from a transversely probed photonic crystal fiber infused with mobile
fluids. The last reported optofluidic device relies on strong fluid/ light interaction to produce either a sensitive index
sensor or a tunable optical filter. The common feature of these various devices is their significant flexibility. Higher
degrees of functionality could be achieved in the future with fully integrated optofluidic platforms that associate complex
microfluidic delivery and mixing schemes with microphotonic devices.
We introduce a novel method of attaining all-optical beam control in an optofluidic device by displacing an optically trapped silica micro-sphere though a light beam. The micro-sphere causes the beam to be refracted by various degrees as a function of the sphere position, providing tunable attenuation and beam-steering in the device. The device itself consists of the manipulated light beam extending between two buried waveguides which are on either side of a
microfluidic channel. This channel contains the micro-spheres which are suspended in water. We simulate this geometry using the Finite Difference Time Domain method and find good agreement between simulation and experiment.
Hydrostatic actuation is a novel method of actuation in Micro Electro Mechanical Systems (MEMS) and provides advantages over other actuation techniques in current use. Hydrostatic actuation utilises a contained pressurised medium to straighten a bent hollow beam, similar to the Bourdon tube used to measure pressure in the macro world. Research has commenced at RMIT University to design and fabricate a microgripper prototype to validate this work. To simplify the design of this microgripper a virtual prototype has been initiated. This paper looks at the work carried out and verification of this virtual prototype using mathematical and finite element modelling. Further work to be undertaken will also be discussed.