These guidelines specify testing procedures and conditions for power light-emitting diodes (power LEDs) and/or high brightness light-emitting diodes (HB LEDs) – in the following referred to as LEDs – which are typically used in the operating regime of the forward current of 100mA and above, and emit visible light1). The application of these guidelines is recommended for packaged LEDs

1. with a total electrical power consumption above 0.5 W,

2. which have energy conversion efficiency above 5%,

3. that are measured and considered as a single light source.

This document is restricted to LEDs which have an exposed cooling surface. Guidelines provided here refer to laboratory measurements. Issues of high speed bulk measurements of LEDs (such as in-line testing aimed for, e.g., binning) are dealt with by other standardization bodies such as the relevant technical committees of CIE. Recommendations given in this document are valid for LEDs powered by DC forward current only. Measurement issues of AC power driven LEDs will be dealt with in future documents.