Table 1.
Summary of estimated expanded uncertainties (2 standard deviation estimates) in percent of spectral radiance values. The final expanded uncertainty relative to SI units is the square root of the quadrature sum of the individual uncertainties
| Source of uncertainty | Wavelength (nm) | |||||
|---|---|---|---|---|---|---|
| 230 | 250 | 300 | 350 | 400 | ||
| 1) | Temperature scale | 1.20 | 1.09 | 0.92 | 0.78 | 0.69 |
| 2) | Blackbody quality | 0.19 | 0.16 | 0.12 | 0.09 | 0.06 |
| 3) | Calibration of pyrometer lamp relative to the International Temperature Scale (ITS-90) | 0.68 | 0.63 | 0.52 | 0.45 | 0.39 |
| 4) | Temperature determination of blackbody and transfer of blackbody spectral radiance to test | 1.68 | 0.53 | 0.20 | 0.07 | 0.07 |
| 5) | Short term source drift | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 |
| 6) | Polarization effects | 0.01 | 0.01 | 0.02 | 0.03 | 0.04 |
| 7) | Size of source effects | 0.30 | 0.30 | 0.25 | 0.20 | 0.15 |
| 8) | Lamp current measurement | 0.17 | 0.16 | 0.14 | 0.12 | 0.10 |
| 9) | Wavelength measurement | 0.24 | 0.22 | 0.18 | 0.16 | 0.14 |
| Final expanded uncertainty (square root of quadrature sum) | 2.23 | 1.44 | 1.14 | 0.96 | 0.84 | |