Interlaboratory comparison of measurement capabilities for flicker and stroboscopic effects for Ecodesign conformity assessment

Lamps based on LEDs often introduce temporal light modulation (TLM). TLM consists of fluctuations in the emitted light over time and can lead to the perception of temporal light artefacts such as flicker and the stroboscopic effect. Due to the widespread concern about the negative effects of TLM on health and safety, additional regulations (Ecodesign) have been introduced. Since these regulations entered into force, it is important for laboratories to underpin their TLM measurements with SI traceability, and to intercompare their result for validation, because their measurements determine whether an LED lamp is allowed on the European market. Therefore, an interlaboratory study of LED lamps was conducted to validate laboratories’ capabilities and methods for TLM measurements of light sources. Overall, the developed models and evaluated uncertainties perform consistently, especially for optical TLM measurements of well-controlled sources with built-in power supply.