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In the industrial production process , the temperature is a very important physical quantities . However , on many occasions , to accurately measure the temperature is very difficult , so the temperature monitoring innovation, research and development has been ongoing . Fluorescent fiber optic temperature sensor because of its high sensitivity , corrosion resistance , electrical insulation and good , simple structure , small size , light weight , fast response , information capacity , low power consumption , etc. , is becoming the most active areas of research and development one . In this paper, on the basis of previous work , study and design of sensitive materials set Cr3: YAG as the fluorescent optical fiber temperature measurement system , in order to achieve real-time measurement of temperature in special circumstances . Thesis describes the mechanism of fluorescence generated , several common fluorescent material , the general characteristics of the fluorescent material was analyzed , elaborated on this basis the mechanism of fluorescence thermometry analysis of the relationship of fluorescence lifetime and temperature , provides a theoretical guarantee for the entire fluorescence optical fiber temperature measurement system . Then study the basic structure of the fluorescent optical fiber temperature measurement system from the optical fiber , light sources , photodetectors, optical coupler device works and the basic characteristics of the analysis , and on this basis , a reasonable choice of various components . The error generated in order to solve the excitation light leakage problem using the dual pulse modulation reference signal of the lock - in detection technique to detect the fluorescence lifetime , according to the basic working principle of the phase locked loop , and the loop , and loop model of the PLL the has excellent performance. On this basis , introduces the basic two-phase locking detection method and design of this phase-locked loop . Final design of a fluorescent optical fiber temperature measurement system , including the light source and its drive circuit , fluorescent fiber optic probes , photoelectric detector and preamplifier circuit, filter circuit and the design of the SCM system and the entire system of experimental studies , experiments show that , the system has good sensitivity and precision , has some practical value .
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