Numerical model for light propagation and light intensity distribution inside coated fused silica capillaries

Abstract

Numerical simulations of light propagation through capillaries have been reported to a limited extent in the literature for uses such as flow-cell design. These have been restricted to prediction of light path for very specific cases to date. In this paper, a new numerical model of light propagation through multi-walled cylindrical systems, to represent coated and uncoated capillaries is presented. This model allows for light ray paths and light intensity distribution within the capillary to be predicted. Macro-scale (using PMMA and PC cylinders) and micro-scale (using PTFE coated fused silica capillaries) experiments were conducted to validate the model's accuracy. These experimental validations have shown encouragingly good agreement between theoretical predictions and measured results, which could allow for optimisation of associated regions for monolith synthesis and use in fluidic chromatography, optical detection systems and flow cells for capillary electrophoresis and flow injection analysis.

Fibre coupled micro-light emitting diode array light source with integrated band-pass filter for fluorescence detection in miniaturised analytical systems

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Controlled Ultraviolet (UV) Photoinitiated Fabrication of Monolithic Porous Layer Open Tubular (monoPLOT) Capillary Columns for Chromatographic Applications

“…The reason for the increased rate of polymer growth is assumed to be from light scattering within the capillary. The propagation of light through fused-silica capillaries has already been well-documented, , and it has been shown that the capillary can transmit a considerable amount of light along its length. During dynamic fabrication, the capillary was exposed to some UV radiation before being drawn into the UV chamber, because of light propagation along the capillary.…”