Abstract
Integrating-sphere sources are convenient for use as near-Lambertian sources to use for calibrating units under test (UUT). An alternative technique is the lamp-plaque method, wherein a calibrated FEL is used to illuminate a polytetrafluoroethylene (PTFE) plaque normally, which in turn is viewed at or 45-degrees off normal by the UUT. This begets several difficulties that should be addressed, including obliquity factors and variable distance of the FEL to points on the plaque, the angular variation of the FEL's intensity, extension of the FEL's calibration as an irradiance standard varying directions and distances, and non-ideality of the Lambertian nature of PTFE. All of these aspects will be discussed.
Analysis of Systematic Effects in 0/45 Lamp-plaque Sensor Calibration
Integrating-sphere sources are convenient for use as near-Lambertian sources to use for calibrating units under test (UUT). An alternative technique is the lamp-plaque method, wherein a calibrated FEL is used to illuminate a polytetrafluoroethylene (PTFE) plaque normally, which in turn is viewed at or 45-degrees off normal by the UUT. This begets several difficulties that should be addressed, including obliquity factors and variable distance of the FEL to points on the plaque, the angular variation of the FEL's intensity, extension of the FEL's calibration as an irradiance standard varying directions and distances, and non-ideality of the Lambertian nature of PTFE. All of these aspects will be discussed.