Light detection: New light detectors for new light sources
Optical technologies are important for many applications: information & communication including fibre optic networks, earth observation, manufacturing, healthcare & life science, lighting & displays, and photonics for safety & security. Accessing the advantages offered by optical technologies in every one of these fields requires that there must be an “eye” to see the light or optical power. Photodetectors, which are sensors and measurers of light, act as this eye. Historically the standards for optical power (or radiometry) have been based on the requirements of incandescent lighting, and the advent of Solid State Lighting (SSL) brings new challenges and opportunities for optical traceability. This project improved photodetector efficiency and provided simpler traceability routes and lower uncertainties for the radiometric units, used to measure light. It developed new primary standards for radiometry based on Predictable Quantum Efficiency Detectors (PQED) that for the first time can be easily used by calibration and testing laboratories, improving access to the candela, the SI unit of luminous intensity.