A new type optical fiber sensor for measuring liquid level

In order to measure the level of a flammable liquid, a new type optic fiber pressure sensor is designed by using the mechanism of optical fiber macro-bend loss, which is mainly composed of an optic fiber ring and an elastic diaphragm. In the measurement system a high precision circuit of pressure demodulation is proposed, which can reduce the influence of the disturbance signal, such as the light intensity fluctuation of the incident light source, temperature and humidity, and etc. The experiment shows that the senor has the characters of reliability and high accuracy.