A high-sensitivity microfluidic flowmeter based on microfiber coupler

In this paper, we utilize a microfiber coupler (MFC) to realize the measurement of the microfluidic flow rate. A glass capillary is chosen as the microfluidic channel. The capillary is coated with gold film. The MFC is wrapped around the gold film which is to heat the device. One kind of UV adhesive is selected to package the device and isolate it from the ambient. The flow rate of the microfluidics is determined by the wavelength shift of the MFC. The flowmeter shows a very high sensitivity of 0.82 nm/(µl/s) when the microfluidic flow rate is 1 µl/s.