Pyrometry for Temperature Measurements
Temperature measurement is central in all aspects of engineering and scientific research. The use of thermocouples to measure temperature is well known and documented.1 The application of thermocouples in temperature measurement is often confined to relatively ideal environments where the presence of necessary thermocouple lead wires to facilitate measurement is acceptable and possible. To use thermocouples to measure temperature in hostile environments, it is usually necessary to provide them with adequate protection, such as an inert atmosphere or suitable coating barriers to protect against damage often due to oxidation. Even so, measurement is generally still often restricted to temperatures well below the thermocouple material’s melting point, currently lower than 293 0°C for the highest temperature tungsten-rhenium material combination. It also may happen that the target object is located very far away that it is impossible to connect by wires, e.g. to measure the temperature of the universe’s cosmic background. In these applications, pyrometry is best suited and is often the only method to choose if radiation is all that is available from the target of interest whose temperature one wishes to know.
KeywordsTemperature Measurement Thermal Barrier Coating Radiation Spectrum Optical Metrology Quartz Lamp
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