Precision calibrating method of infrared thermometer with wide temperature range

The invention discloses a precision calibrating method of an infrared thermometer with a wide temperature range; the method comprises the steps: firstly, acquiring initial temperature values measured by the infrared thermometer according to experiments and drawing into a discrete point drawing; performing segmented fitting for the initial temperature values acquired by the infrared thermometer and a true temperature curve by means of a least square method, and acquiring a correction coefficient of each temperature interval; and finally, correcting the initial temperature values according to the corresponding correction coefficients of the initial temperature values, acquired by the infrared thermometer, in the temperature intervals and acquiring one temperature value which is closer to the actual temperature than the initial temperature values. The measuring precision of the infrared thermometer is improved and the measuring error is reduced.