Today, the SSLC Platform published a new paper on Temporal Light Artifacts (TLAs) which are undesired visual perceptual effects, caused by Temporal Light Modulations (TLMs) that commonly exist in lighting systems, especially LED lighting systems. Accurate measurement of TLM and evaluation of TLA metrics, specifically the stroboscopic visibility measure (SVM) and the short-term flicker indicator (PstLM), are required by certain product safety regulations with limit values specified. This paper investigates the impact of different measurement conditions on the PstLM and SVM for 11 different commercial lamps. The paper reports that the sampling rate, filter setting and measurement duration are critical for PstLM measurements, and anti-aliasing filters are essential for PstLM measurements, but for some waveforms, PstLM results may be inaccurate even under the conditions recommended by the International Electrotechnical Commission (IEC). The variation of PstLM at different sampling rates is slightly larger when using analogue filters as compared to digital filters. For SVM measurements, different sampling rates and measurement durations have a significant impact on the results. It is recommended to use a combination of zero-padding and quadratic interpolation (ZPQI method) to obtain accurate and consistent SVM results. Overall, the use of different filtering methods (digital or physical) has little effect on the results of the PstLM and SVM calculations, higher order filters are recommended.

The paper can be found here in our publications Library: https://www.iea-4e.org/wp-content/uploads/2025/02/Li-and-Ohno-2025-Analysis-of-PstLM-and-SVM-variations-LRT-24-0048-accepted.pdf