Measuring the radiation coefficient distribution and surface temperature distribution of a tungsten body heated by a powerful laser

In this article, we present what we believe to be the first successful demonstration of the emissivity distribution together with the temperature distribution of a tungsten plate at the laser heating spot. The measurements were made in the 740–800 nm wavelength range by using the multispectral imaging method on a laser-heating apparatus with a tandem acousto-optic filter (TAOTF). The TAOTF consists of two conjugated acousto-optic crystals connected to a high-definition video camera. The emissivity measurement error was less 7% for a maximum point temperature (2540 K) at the laser heating spot.