Fig. 1. Spectral radiation characteristics of an ideal blackbody at different temperatures

Fig. 2. Camera imaging system model

Fig. 3. Curves of single wavelength single temperature measurement range under different wavelengths

Fig. 4. Single temperature measurement range of colorimetric thermometry

Fig. 5. Induction eddy current heating device

Fig. 6. Gray-temperature fitting curves at two wavelengths

Fig. 7. Gray-temperature fitting curve for two exposure time

Fig. 8. Experimental arrangement of on-line measurement of molten pool temperature

Fig. 9. Evolution of molten pool temperature field with time during printing