Liquid Level Sensing Application Based on Optical Chaos

The application of liquid level sensing based on optical chaos is proposed and experimentally demonstrated. The liquid level sensor is a segment of no-core fiber (NCF) with a faraday reflection mirror (FRM) attached next to it, and with the filtering of a fiber Bragg grating (FBG), the intensity of the reflection light from the sensor is modulated by the liquid level. By monitoring the position and amplitude of the peak in the correlation curve, the measurement of liquid level and the locating of sensing point can be simultaneously achieved. Experimental result shows a linear range of 3.8 cm. This demodulation method also shows the ability of precise fault locating with the accuracy of several centimeters, making it easy for network maintenance.