Evaluation of FEL lamp seasoning behavior for use as a spectral irradiance standard

This work presents seasoning behavior from a set of 1000 W FEL-type lamp concerning its qualification to be used as a secondary spectral irradiance standard. The lamps from the set were made from two different manufactures and were seasoned for a period of 40 hours. During the seasoning, lamp relative drift of irradiance, illuminance, current and voltage were measured at each 3 minutes and lamp spectral irradiance relative drift was measured 4 times. It was observed significant temperature dependence in the irradiance measurement related to meter readout circuit. Despite the temperature effect, it was obtained the average irradiance stability up to 0.03%/h and illuminance stability up to 0.02%/h.