Page 75 - Optofluidics Fundamentals, Devices, and Applications

56 Cha pte r T h ree

systems “work” optically: one can make optofluidic analogs of vari-
ous familiar devices, such as waveguides and lenses; one can manip-
ulate light in ways that cannot be accomplished using conventional
solid-state devices. The question now is “Who cares?”
It is unlikely that this class of optofluidic devices will compete
with conventional, solid-state devices in optical communications,
where durability and stability are of paramount importance. Optoflu-
idic systems seem, however, to be well suited for bioanalysis and lab-
on-a-chip systems, where the samples are usually present in aqueous
solutions, and where it is possible to use the strategy of cofabrication
to generate multiple useful functions, from analysis and generation
of light to the manipulation of particles using magnetic fields, in
devices made using a single step of fabrication [16,17]. A wide range
of applications in biomedicine, food testing, environmental testing,
biological research, drug testing, forensics, and homeland security all
seem plausible.
Optics is an area that has followed a paradigm—solid-state fabri-
cation focused on ultrahigh optical performance and durability, but
2
with minimal adaptability. L systems suggest another paradigm:
systems that only function when they operate in dissipative mode—
for example, with fluids flowing through them—and in which the
systems are intrinsically unstable but highly adaptable. Time will tell
the value of these characteristics.

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