# About LED Flicker and Dimming



## Black Dog (Oct 16, 2011)

randolph333 said:


> Poplawski, Michael. “What You Need to Know about LED Flicker and Dimming.” presented at the LIGHTFAIR, Las Vegas, NV, May 9, 2012.
> 
> Looks like a pretty good overview. It is a few years old, however, and the story may be different now.


Good stuff..:thumbsup:


----------



## Electric_Light (Apr 6, 2010)

randolph333 said:


> Poplawski, Michael. “What You Need to Know about LED Flicker and Dimming.” presented at the LIGHTFAIR, Las Vegas, NV, May 9, 2012.
> 
> Looks like a pretty good overview. It is a few years old, however, and the story may be different now.


Pay attention to tail lights on newer buses and high-end vehicles. Driving/parking lights appear like series of dots while brake lights (full brightness) appear "solid". 

You'll have a more consistent color across the entire dimming range using this type of dimming but it will produce the "dotting" effects and it produces far more RFI. Depending on the frequency, it also makes it more likely to have problems with interfering with other people's communication equipment and possibly run into a problem with the FCC. 

Another method directly varies the actual current flowing through the LED. The light color is more likely to shift as you dim especially in the very low range, but minimal flicker and less RFI. Usually the FCC Class B (residential use) type uses this kind.


----------

