1 research outputs found
Micromachined Fused Silica Liquid Core Waveguide Capillary Flow Cell
A planar,
chip-based flow cell for UV–vis absorbance detection
in HPLC is presented. The device features a microfabricated free-standing
liquid core waveguide (LCW) capillary detection tube of long path
length that is based on total internal reflection. We report on the
linearity and calibration slope characteristics of lithographically
produced LCWs with different interior/exterior geometries. 3D ray
tracing was indispensable in modeling behavior in the more demanding
geometries: multipath behavior may be intrinsic to these waveguides
with consequent nonlinearity. Fortunately, nonlinearity in lithographically
easy-to-produce waveguide geometries (such as with a flat, concave
exterior and a round interior) is not as detrimental as might be initially
expected. Experimental performance is predictably affected by the
attainable surface quality of the LCW and efficient and reproducible
coupling of the input light into the LCW