To meet the demand of the steel production automation

a novel hot-metal detector whose operating principle is based on infrared detection is developed.The selection of the optoelectronic detector and the design of the scanning mirror as well as the signal processing circuit are also analyzed in detail.The calculation formula for the scanning angle of the cylindrical mirror which has the function of scanning and focusing is also presented;this formula offers the theoretical gist for the design of the scanning system.The testing results are as follow: the detecting angle amount to 2°×20°

the detection probability is better than 0.95 and the false alarm probability is less than 10-6.The detector can work under the execrable surroundings.