Microscale Liquid Marble-Based Tilt Motion Sensor Using Optical Fiber Fabry-Perot Interference

We demonstrate a miniature and low-cost liquid marble-based optical fiber tilt angle sensor prototype with advantages of simple fabrication, immunity to electromagnetic interference, high linearity and available differential detection by using Fabry-Perot (F-P) interferometric detection. A mercury marble, working as a light reflector, is dispensed into a capillary tube preprocessed by hydrophobic agent. The gravitational acceleration solved by tilt angle in the range of 0-90 degrees exhibits a fitted linear sensitivity of 3.72 mu m/ms(-2), in agreement well with the governing model incorporating with the effect of contact angle hysteresis between the droplet and the substrate.