What is Flicker Metrics (Percent Flicker, Flicker Index, SVM) ?

Flicker

Light Flicker Measurement

This article compares three flicker metrics regarding percent flicker, flicker index and SVM. The comparison includes the definition comes from which organization, the definition of itself, calculation formula and the description of the range. If you want to know more about which products have related measurement functions, please click on the relative products tab.

Index Defined By Definition Point Formula Index Range
Percent Flicker Illuminating Engineering Society (IES) A relative measure of the cyclic variation in the amplitude of a light. 0% ~ 100%
The lower the percent flicker, the less substantial the flicker.
Flicker Index Illuminating Engineering Society (IES) A measure of the cyclic variation taking into account the shape of the waveform. 0 ~ 1
The lower the flicker index, the less substantial the flicker.
SVM (Stroboscopic Effect Visibility Measure) PHILIPS & CIE Time domain → frequency domain.
Summation of weighted Fourier components
SVM < 1,Not Visible
SVM > 1,Visible
SVM = 1,Just Visible

Reference: (old references since inactivated)

https://www.designlights.org/news-events/events/stakeholder-meeting-2016/presentation-downloads/temporal-light-artifacts-flicker-and-stroboscopic-effect/

http://www.yidianzixun.com/article/0EmpHcjR

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This article compares three flicker metrics regarding percent flicker, flicker index and SVM. The comparison includes the definition comes from which organization, the definition of itself, calculation formula and the description of the range. If you want to know more about which products have related measurement functions, please click on the relative products tab. Read More

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About UPRtek

United Power Research and Technology

UPRtek (est. 2010) is a manufacturer of portable, high-precision light measurement instruments; Handheld Spectrometers, PAR meters, Spectroradiometers, Light Calibration Solutions.

UPRtek HQ, R&D and manufacturing are all based out of Taiwan, with Worldwide representation through our certified Global Resellers.

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Spectral Devices

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In the realm of spectral devices, three devices stand out: a Spectrometer, a Spectrophotometer, and a Spectroradiometer.

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