Calibration standards are employed in determining the correlation between an input and an output quantity. In radiometry, sources and detectors of optical radiation provide the input quantity. Several different types of calibration standards are required to cover the large number of measurement quantities associated photometry) and radiometry.
Both source and detector reference standards are employed in calibration work. Also, cameras, optical systems, video recorders, digital cameras and other imaging equipment require calibration of their uniformity. Here the input quantity is provided by a light source with uniform (hemispherical) emissivity characteristics. These luminance standard light sources are typically integrating sphere based. Optically diffuse materials are also used as reflectance transfer standards. Gigahertz-Optik provides DKD accredited, PTB and NIST traceable certified calibration reference standards.
