Fig. 1. Schematic diagram of the mid-infrared radiometer

Fig. 2. Photo of the mid-infrared radiometer

Fig. 3. (a) Optical design results of the mid-infrared radiometer; (b) Spot diagram; (c) Aberration; (d) Field curvature and distortion

Fig. 4. (a) Radial mounting and fixing structure of lens; (b) Axial mounting and fixing structure of lens

Fig. 5. Schematic diagram of thermal control structure of modulator

Fig. 6. Gain measurement of the mid-infrared radiometer

Fig. 7. Block diagram of signal processing

Fig. 8. Calibration scene of the mid-infrared radiometer under vacuum and low temperature environment

Fig. 9. Calibration of temperature response of the mid-infrared radio-meter under low temperature condition

Fig. 10. Calibration of temperature response of the mid-infrared radiometer under high temperature condition