Fig. 1. Radiative transfer process of black-body energy calibration

Fig. 2. Geometric relation diagram of black-body， target and entrance pupil

Fig. 3. Radiative transfer process of infrared optical system energy calibration

Fig. 4. Block diagram of transmittance measurement device

Fig. 5. Target image of transmission energy calibration for large aperture infrared optical system

Fig. 6. Image of energy calibration for black-body