Time-resolved, local temperature measurements during pulsed laser heating

To analyse processes during laser heating, one needs to be able to measure temperatures of about 1000K within one microsecond and with micrometre resolution. To achieve this accuracy, we set up a high-performance optical detection system with a microsecond gated camera in combination with selected interference filters to detect the thermal emission spectrum in the visible range. By fitting the emission spectrum to Planck's law, we are able to collect an area temperature profile for time intervals as short as one microsecond. Thus we can show that a polymer film, which is doped with an organic dye for energy conversion, can reach temperatures of at least 900 K, which is high above its 'normal' decomposition temperature. It is, furthermore, possible to relate the temperature to the effect of the laser beam on the polymer film.