There are many advantages to fiber optic temperature sensors, but there are almost no disadvantages. In terms of price, it may be slightly more expensive than traditional PT100 temperature sensors. For traditional sensors, such as PT100 temperature sensors, there are obvious advantages.
Fiber optic temperature sensors can be divided into functional fiber optic temperature sensors and transmission fiber optic temperature sensors according to their working principles
Functional fiber optic temperature sensors utilize the various characteristics of optical fibers (such as phase, polarization, intensity, etc.) that vary with temperature for temperature measurement. Although this type of sensor has the characteristic of integrating transmission and sensing, it also increases the difficulty of sensitization and desensitization.
The optical fiber of the transmission type fiber optic temperature sensor only serves the purpose of optical signal transmission to avoid the complex environment of the temperature measurement area. The modulation function of the measured object is achieved by other sensitive components with physical properties. This type of sensor increases the complexity of the system due to the optical coupling problem between the fiber optic and the sensing head, and is more sensitive to interference such as mechanical vibration.
Fiber optic fluorescence temperature sensor
Fiber optic fluorescence temperature sensor is currently a new type of temperature sensor that is actively researched. The working mechanism of fluorescence temperature measurement is based on the basic physical phenomenon of photoluminescence.
The so-called photoluminescence is a phenomenon of light emission, which occurs when a material is excited by light in the ultraviolet, visible, or infrared regions. The fluorescence parameters emitted have a one-to-one correspondence with temperature, and the required temperature can be obtained by detecting their fluorescence intensity or fluorescence lifetime.
1. In electromagnetic/radio frequency environments, traditional temperature measurement methods are severely affected and cannot function properly;
2. Has particularly high requirements for accuracy, sensitivity, lifespan, stability/reliability, etc;
3. The installation environment is narrow and has special requirements for sensor size;
4. Flammable, explosive, and corrosive environments have special requirements for safety/corrosion resistance.
5. Lightning strikes, outdoor and other harsh environments.
6. Difficulties in energy supply at the testing site.
Fiber optic fluorescence temperature sensors have their own unique advantages compared to other fiber optic temperature sensors: due to the inherent relationship between fluorescence lifetime and temperature, which is independent of light intensity, self aligning fiber optic temperature sensors can be made. However, general fiber optic temperature sensors based on light intensity detection require frequent calibration due to the fact that the optical transmission characteristics of the system are often related to transmission fibers and fiber couplers.