One-day Training course on the measurement of temporal light modulation (TLM)

The consortium of EMPIR project Metrology for Temporal Light Modulation (20NRM01, MetTLM) invites you to a one-day training course on the measurement of temporal light modulation (TLM).

Content of the training

The course will include:

  • Equipment specification, characterisation and calibration
  • Methods of measurements in laboratory settings and field measurements
  • Sources of measurement uncertainty originating from the measurement devices or modulated light sources under test
  • Practical demonstrations of systematic measurement errors arising during the determination of TLM and TLA metrics, with advice on how to avoid common potential errors
  • Introduction of validation and verification of methods for traceable TLM measurement
  • Issues in results from imaging luminance measurement devices originating from temporal light modulation with respect to different measurement principles, i.e. a global shutter or rolling shutter, will be considered.


The training will also include demonstrations of temporal light artefacts in the optical measurement laboratories of PTB and provide the possibility for a hands-on on TLM measurement devices from different manufactures available in the MetTLM consortium.

Targeted audience and prerequisites

The training session addresses technicians and engineers of testing laboratories, National Metrology Institutes and manufacturers of instruments and luminaires who are interested measurement and measurement uncertainty of TLM.

Participants are expected to already have substantial knowledge in the field of Temporal Light Modulation prior to the event, i.e. knowledge of metrics for TLM and TLA, as well as on principles regarding traceability and measurement uncertainty. In particular, it is requested that each participant already has the Technical Report CIE 249:2022 “Visual Aspects of Time-Modulated Lighting Systems” at hand.

Participants are expected to be familiar with the vocabulary of CIE Technical Note 012:2021, eco design regulation (Ecodesign Directive 2009/125/EC), and with the basics of ISO/IEC Guide 99:2007-12 (VIM) and JCGM 100:2008 “Guide to the expression of uncertainty in measurement (GUM)” including its Supplement 1 (JCGM 101:2008) and Supplement 2 (JCGM 102:2011).


Please contact  by 10 April 2024.

Subsequently a confirmation of registration and detailed information about the agenda including the training location and useful information on public transport will be provided.

Practical Information

The training course is provided free of charge as an in-person event for one full day in Braunschweig, Germany. Participants need to cover their own travel expenses.

Registration by 10 April is required. Due to the practical demonstrations the number of participants is restricted.

About the project

LED-based lighting contributes to energy saving and the reduction of the environmental impact of lighting. However, LED lamps can show fluctuations in the light output known as temporal light modulation (TLM) which could, above certain limits and under certain conditions, impact the health, well-being and safety of people.

New methods and metrics will help the automotive, entertainment and lighting industries quantify the significance of these effects and so support development of improved product safety and consumer appeal. Appropriate standardisation will also support compliance with regulations and support the phase-out of incandescent lighting, and so contribute to reduced carbon emissions across Europe.

For more information see

This EMPIR project is co-funded by the European Union's Horizon 2020 research and innovation programme and the EMPIR Participating States