Variable optofluidic slit aperture

Slit and Aperture Selection in Spectroradiometry

Satiated relative permeability of variable-aperture fractures.

Experimental studies of capillary-dominated displacements in variable-aperture fractures have demonstrated the occurrence of a satiated state at the end of invasion, where significant entrapment of the displaced phase occurs. The structure of this entrapped phase controls the behavior of flow and transport processes in the flowing phase. Recent studies have shown that the areal saturation of th...

Optical switch based on variable aperture.

We report on a pixel whose aperture can be varied electrically. The pixel is confined by a hole-patterned polymer wall and a dielectric liquid forms a ring shape around the wall surface. Without an electric field, the pixel has the largest aperture. The applied fringing field stretches the liquid surface, leading to a decrease in the aperture size. The switchable aperture ratio of the pixel is ...

Tunable optofluidic aperture configured by a liquid-core/liquid-cladding structure.

Miniaturized and tunable optical components, such as the waveguide, lens, and prism, have been of great interest for lab-on-chip systems. This Letter reports an optofluidic aperture stop formed by the liquid-core/liquid-cladding flow. The aperture size can be tuned accordingly by adjusting the flow rates. Manipulation of the aperture size allows control of the amount of light passing through th...

Variable Numerical-Aperture Temporal-Coherence Measurement of Resonant-Cavity LEDs

The first interferometric measurements of temporalcoherence length variation with numerical aperture (NA) are described for 650 nm, resonant-cavity light-emitting diodes (LEDs) agreeing with spectrally derived results. The interferometrically measured coherence length (22 m to 32 m) reduced by 37% for a 0.42 increase in NA. For a larger range of NA (0–1), this would give coherence lengths (10 m...