title: Performance evaluation of an infrared thermocouple.
abstract: The measurement of the leaf temperature of forests or agricultural plants is an important technique for the monitoring of the physiological state of crops. The infrared thermometer is a convenient device due to its fast response and nondestructive measurement technique. Nowadays, a novel infrared thermocouple, developed with the same measurement principle of the infrared thermometer but using a different detector, has been commercialized for non-contact temperature measurement. The performances of two-kinds of infrared thermocouples were evaluated in this study. The standard temperature was maintained by a temperature calibrator and a special black cavity device. The results indicated that both types of infrared thermocouples had good precision. The error distribution ranged from -1.8 °C to 18 °C as the reading values served as the true values. Within the range from 13 °C to 37 °C, the adequate calibration equations were the high-order polynomial equations. Within the narrower range from 20 °C to 35 °C, the adequate equation was a linear equation for one sensor and a two-order polynomial equation for the other sensor. The accuracy of the two kinds of infrared thermocouple was improved by nearly 0.4 °C with the calibration equations. These devices could serve as mobile monitoring tools for in situ and real time routine estimation of leaf temperatures.
authors.affiliation: Department of Bio-industrial Mechatronics Engineering, National ChungHsing University, 250 Kuokuang Road, Taichung, Taiwan. ccchen@dragon.nchu.edu.tw
authors.forename: Chiachung
authors.initials: C
authors.lastname: Chen
authors.forename: Yu-Kai
authors.initials: YK
authors.lastname: Weng
authors.forename: Te-Ching
authors.initials: TC
authors.lastname: Shen
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002138:Calibration; D018515:Plant Leaves / Q000737:chemistry / Q000502:physiology; D013696:Temperature; D013821:Thermometers