Fig. 1. The actual camera imaging model

Fig. 2. Camera calibrated light path diagram

Fig. 3. Digital image correlation method

Fig. 4. High-temperature DIC measurement system

Fig. 5. Camera calibration scene in laboratory

Fig. 6. Influence of the distance between the glass and the camera on calibration accuracy

Fig. 7. Actual calibration environment

Fig. 8. Mean values of total displacement

Fig. 9. Mean value and standard deviation of displacement in X, Y and Z axes

Fig. 10. Mean values of maximum principal strain

Fig. 11. Strain mean value and standard deviation in the X and Y directions

Fig. 12. Displacement variation in the X, Y and Z directions for the calibration with and without glass with temperature from 50 °C to 120 °C

Fig. 13. Measurement coordinate system and key points

Fig. 14. The mean displacement of parallel lines in different directions