Infrared target temperature correction system and method
Infrared Ir Thermometer Calibration Systems and Methods are Disclosed in which the temperature of an IR thermometer calibration system is controlled such that radiation emitted by a target at a given input temperature is equal to the radiation emitted by a graybody heated to the input temperature and having an emissivity equal to an emissivity setting of an IR thermometer to be calibrated using the IR thermometer calibration system.
1. A method for calibrating an infrared target comprising:
taking a plurality of first radiance measurements of an infrared target, each of the plurality of radiance measurements being taken with the infrared target heated to one of a plurality of target set temperatures;
for each first radiance measurement calculating an apparent temperature of a graybody having a radiance equal to the first radiance measurement and having an emissivity substantially equal to an emissivity setting of an infrared thermometer;
mapping each of the apparent temperatures to one of the plurality of set temperatures corresponding to the same one of the plurality of radiance measurements;
inputting a calibration temperature into a controller coupled to the infrared target;
heating the target to one of the plurality of set temperatures mapped to one of the plurality of apparent temperatures corresponding to the calibration temperature;
taking a radiance measurement of the target with the infrared thermometer; and
calibrating the infrared thermometer to map the radiance measurement to the calibration temperature.
2. The method of claim 1 , wherein taking the plurality of first radiance measurements of the infrared target comprises taking a plurality of first radiance measurements of the infrared target with the infrared thermometer calibrated according to a simulated blackbody.
3. The method of claim 1 , wherein the target has a high-emissivity coating.
4. The method of claim 1 , further comprising measuring a radiance of a subject using the infrared thermometer and outputting a temperature corresponding to the step of calibrating the infrared thermometer.
5. The method of claim 1 , further comprising deriving a plurality of contact temperatures for each of the plurality of set temperatures, the plurality of contact temperatures each corresponding to an output of a sensor in thermal contact with a target when the surface of the target is at the set temperature, wherein the step of heating the target to one of the plurality of set temperatures comprises heating the target such that the temperature sensor produces an output corresponding to the contact temperature corresponding to one of the plurality of set temperatures.
6. The method of claim 1 , wherein the emissivity setting is less than one.
7. The method of claim 6 , wherein the emissivity setting is between about 0.9 and one.
8. The method of claim 7 , wherein the emissivity is between about 0.9 and about 0.95.