Alcance
ISO 20351:2017 specifies a method of absolute measurement (using an integrating sphere) of internal quantum efficiency of phosphor powders which are excited by UV or blue light and emit visible light, and which are used for white light-emitting diodes (LEDs).ISO 20351:2017 can be adopted for the measurement of phosphors used in non-white LEDs, for example, green, orange, pink or purple LEDs.