Fibers for low-temperature radiometric measurements.

Theoretical calculations are presented for the performance of a fiber-optic radiometer which makes use of infrared transmitting fibers to measure low temperatures (near room temperature). We calculate the radiometer spatial resolution, the dependence of the radiometer signal on the surface temperature, and the minimum resolvable temperature difference (MRDeltaAT) of the radiometer. The performance of the fiber-optic radiometer is compared with a conventional optical (thin lens) radiometer.