Abstract

We describe the design and operation of a liquid-core liquid-cladding (L²) lens formed by the laminar flow of three streams of liquids in a microchannel whose width expands laterally in the region where the lens forms. Two streams of liquid with a lower refractive index (the cladding) sandwich a stream of liquid with a higher refractive index (the core). As the core stream enters the expansion chamber, it widens and becomes biconvex in shape, for some rates of flow. This biconvex fluidic element focuses light. Manipulating the relative rates of flow of the streams reconfigures the shape, and therefore the focal distance, of the L² lens.

© 2008 Optical Society of America