Fig. 1. Beer-Lambert law

Fig. 2. CT analysis grid

Fig. 3. Schematic of experiment system

Fig. 4. Laser path distribution of CT cell

Fig. 5. Absorption intensity of the laser

Fig. 6. TDLAT detection results

Fig. 7. Thermocouple detection results

Fig. 8. Results of TDLAT and thermocouple at Y=10 cm

Fig. 9. Results of TDLAT and thermocouple at Y =-10 cm