This study develops a two-color near-infrared non-contact temperature measurement system for AOD converter. We transmitted light ray by the gas path of bottom lance without additional optical unit. It eliminated errors caused by interfering factors such as long optical path, narrow spot or dust, unaffected by the emissivity of the measured object. This system improves the temperature measurement accuracy greatly. The real-time temperature measurement could better control the smelting process and improve the hit rate at the end point. The emissions of furnace slag are effectively reduced, energy consumption is lowered and the quality of steel is improved.
