Application of optical trapping to beam manipulation in optofluidics

We demonstrate a tunable in-plane optofluidic microlens with a 99 light intensity enhancement at the focal point. The microlens is formed by a combination of a tunable divergent air-liquid interface and a static polydimethylsiloxane lens, and is fabricated using standard soft lithography procedures. When liquid flows through a straight channel with a side opening (air reservoir) on the sidewall, the sealed air in the side opening bends into the liquid, forming an air-liquid interface. The curvature of this air-liquid interface can be conveniently and predictably controlled by adjusting the flow rate of the liquid stream in the straight channel. This change in the interface curvature generates a tunable divergence in the incident light beam, in turn tuning the overall focal length of the microlens. The tunability and performance of the lens are experimentally examined, and the experimental data match well with the results from a ray-tracing simulation. Our method features simple fabrication, easy operation, continuous and rapid tuning, and a large tunable range, making it an attractive option for use in lab-on-a-chip devices, particularly in microscopic imaging, cell sorting, and optical trapping/manipulating of microparticles.

Section: Introductionmentioning

confidence: 99%

Tunable optofluidic microlens through active pressure control of an air–liquid interface

Shi

Stratton

Lin

et al. 2009

“…Optical trapping is another control mechanism to create tunability (Domachuk et al 2005). This approach is of great interest, as it allows controlling light with light.…”

Section: Refractive Index Tunabilitymentioning

confidence: 99%

Tunable optofluidic devices

Levy

Shamai

2007

116

The emerging field of optofluidics provides exciting opportunities for the realization of tunable optofluidic devices (TODs) using a large variety of physical mechanisms. This is because microfluidics is a promising technology for achieving a high degree of tunability-a capability that is not available in many of the current optical devices. In addition, microfluidics holds a great potential for rapid prototyping, miniaturization and integration. TODs already find commercial applications in various fields such as display and imaging, and are expected to become a key player in future optical systems for biology, medicine, communication and information processing. We review the recent progress in the field and discuss potential future directions.

“…The use of optical tweezers to displace all-optically one microsphere offers an effective way to control the interaction of the lens with the optical beam delivered by a microphotonic integrated device. On this basis, signal beam manipulation and beam steering functionality are attainable all-optically in optofluidic devices (Domachuk et al 2005b).…”

Section: Optofluidic Devices Based On Optically Trapped Silica Microsmentioning

confidence: 99%

Optofluidics: a novel generation of reconfigurable and adaptive compact architectures

Monat

Domachuk

Grillet

et al. 2007

Self Cite

The integration of microfluidics and microphotonics brings the ability to tune and reconfigure ultracompact 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 abrupt interfaces that can be easily reshaped. Several examples of optofluidic devices are presented here to illustrate the achievement of flexible devices on (semi) planar and compact platforms. First, we report an integrated geometry for a compact and tunable interferometer that exploits a sharp and mobile air/water interface. We then describe a class of optically controlled devices that rely on the actuation of optically trapped micron-sized objects within a fluid environment. The last architecture results from the infiltration of photonic crystal devices with fluids. This produces tunable and reconfigurable photonic devices, like optical switches. Higher degrees of functionality could be achieved with sophisticated optofluidic platforms that associate complex microfluidic delivery and mixing schemes with microphotonic devices. Moreover, optofluidics offers new opportunities for realizing highly responsive and compact sensors.