Opto-mechanical design and performance test of thermal infrared channel field radiometer

To meet the needs of the on-orbit radiometric calibration of remote sensors, an thermal infrared channel field radiometer (TICFR) was developed for on-site measurement. The working principle, optical system design and mechanical structure design of the TICFR were established. Radiometric calibration and calibration uncertainty analysis of the TICFR laboratory were performed. The results show that the received radiance of each TICFR channel has a strong linear relationship with the DN response value. TICFR thermal shock resistance and working environment temperature adaptability experiments were performed. The results show that the TICFR displays strong thermal shock resistance and can be applied in working environments from -20°C to 50°C. To verify the accuracy of the TICFR measurement data and the reliability of the instrument, a field comparison experiment of the TICFR and CE312 was performed at the National High-Resolution Remote Sensing Comprehensive Calibration Field. The results show that the surface brightness temperatures measured by the two devices display the same trend. The average brightness temperature deviation measured by the corresponding channels of the two instruments is less than 0.1K, and the standard deviation is less than 0.3 K; these results confirm that the measurement accuracy and stability of the TICFR are similar to those of the CE312. The TICFR has important applications in remote sensing thermal infrared band site calibration.