Microfluidic device with integrated flow rate sensor is demonstrated. Two glass capillaries and a short length of high light-absorption, Co²⁺-doped fiber were stacked inside another capillary and drawn into a taper, containing two ~40μm diameter microchannels. An FBG was inscribed in the Co²⁺-doped fiber. 1480 nm light was used to heat the Co²⁺-doped fiber and its temperature was measured using an FBG-interrogator operating around 1550nm. The flow rate of the liquid inside in the microchannel can be determined by the temperature and cooling rate of the microchannel. Sensitivity of 0.304nm/(μL/s) and minimum detectable flow rate ~16nL/s were demonstrated.

Date Published: 2 June 2014
PDF: 4 pages
Proc. SPIE 9157, 23rd International Conference on Optical Fibre Sensors, 91573I (2 June 2014); doi: 10.1117/12.2059244

Published in SPIE Proceedings Vol. 9157:
23rd International Conference on Optical Fibre Sensors
José M. López-Higuera; Julian D. C. Jones; Manuel López-Amo; José Luis Santos, Editor(s)