Patent ID: 7104683

Claim:
A method of determining the surface temperature of a sample, the method comprising the steps of: positioning a fiberoptic temperature sensor having a phosphor tip at a first distance from a sample surface; heating the sensor tip to a plurality of temperature levels by subjecting the phosphor tip to a plurality of predetermined laser power levels with the tip positioned at the first distance from the sample surface; measuring the temperature of the phosphor tip at each of the plurality of laser power levels with the tip positioned at the first distance from the sample surface; positioning the phosphor tip at a second distance from the sample surface; heating the sensor tip to a plurality of temperature levels by subjecting the phosphor tip to the same plurality of predetermined laser power levels with the tip positioned at the second distance from the sample surface; measuring the temperature of the sensor tip at each of the plurality of laser power levels with the sensor positioned at the second distance from the sample surface; calculating the difference between the detected temperatures at the first distance and the detected temperatures at the second distance for each of the plurality of laser power levels; and determining the surface temperature of the sample to be the temperature of the phosphor tip when the difference between the detected temperature at the first distance and the detected temperature at the second distance is substantially equal to zero.