Temporal Light Artifacts (TLAs) are undesired visual perceptual effects, caused by Temporal Light Modulations (TLMs), which 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. In this study, we investigated the impact of different measurement conditions on the PstLM and SVM for the measured waveforms of 11 different commercial lamps. It is found that the sampling rate, filter setting and measurement duration are critical for PstLM. 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 analog filters compared to digital filters. For SVM, 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.

Jiaye Li 1,2*, Yoshi Ohno 1
1National Institute of Standards and Technology, Gaithersburg, MD, USA
2École nationale des travaux publics de l’État, Vaulx-en-Velin, France

Li J, Ohno Y. Analysis of PstLM and stroboscopic visibility measure variations due to different measurement conditions. Lighting Research & Technology. 2025;0(0). doi:10.1177/14771535251315475
Link: Published paper in LR&T