Fig. 1. Schematics diagram of the system

Fig. 2. Infrared radiation measurement unit

Fig. 3. Transmittance curve of filter. (a) Detector 1 filter; (b) Detector 2 filter; (c) Window filter

Fig. 4. Calibration experiment of internal radiation equivalent blackbody temperature measurement

Fig. 5. Detector response curves at different working temperatures (a) Detector 1; (b) Detector 2 不同工作温度 下探测器的响应曲线 。（a）探测器 1；（b）探测器 2

Fig. 6. Working temperature correction function curve f_b1(T_b) of detector 1 探测器 1工作温度修正函数曲线

Fig. 7. Radiation calibration of target temperature

Fig. 8. Calibration results of the target temperature

Fig. 9. Results of the designed system compared to the Pt100 sensor in the outfield. (a) Measurement results; (b)Correlation