Influence of natural convection on beam propagation in fluidic optical device

The fluidic optical device by means of the thermal lens effect has attracted increasing attention as a flexible beam shaper. However, onset of natural convection inhibits operation of the fluidic optical device as it causes asymmetric distortion on shaped beam profile. For implementation of the fluidic beam shaper, this adverse effect should be controlled in terms of the beam profile change. From this perspective, we investigated the influence of natural convection on the propagating beam profile through the fluidic optical device by means of CW laser induced the thermal lens effect. Numerical method taking advantage of beam propagation method was used to calculate modulation of the probe beam profile. The calculated results demonstrated good agreements with several experimental results. Using this numerical model, the parametric study to control asymmetry and quality of the annular beam was performed quantitatively in the dual beam thermal lens system. The core of this study is that the solution of the simple pentadiagonal equation can provide the crucial investigation on the modulation of the beam profile in the fluidic optical device with natural convection.