Multiple Channel Fiber-optic Thermometer Based On Sapphire-fiber

Fiber optic temperature sensor is one of the key techniques for the measurement of temperature, with anti-electromagnetic interference, wide measuring range, high precision of temperature measurement, distributed measurement. Therefore, the related technology has been developed rapidly in the past decades, and a variety of optical fiber sensors have been applied.In this thesis, we report a novel digital iteration algorithm for fluorescence lifetime measurement, which is proved suitable for the fluorescence lifetime-based multi-probe fiber thermometer application. The algorithm utilizes only one set of fluorescence decay sampling data to decide the fluorescence lifetime by using the basic approaches of addition and subtraction. Iteration times of about 10-12 are sufficient to reach the final stable value. As a result, the algorithm features robust, high efficiency, strong anti-noise and immune to background level. The algorithm has been successfully used in a sapphire fiber -based multi-probe thermometer covering the temperature range from room temperature to 1000? and confirmed suitable for practical application.An eight channel red sapphire fiber temperature sensor have been developed, and the development of the sensor is described in detail, including the optical system, processing circuit and temperature calibration. The fiber sensor cover temperature range from room temperature to 1000?, resolution up to 1 ? and has a high sensitivity to meet the requirements of high precision, wide range and real-time temperature measurement. The system is stable for a long time and has good application prospects.