Most modern LED lighting flickers. By this, I mean that the light turns on and off very quickly… from 50 to 1000 times per second. This is often done to power the light with an inexpensive power supply or to control the brightness inexpensively.

Roughly 5-10% of people can see and are bothered by this flickering! This affects many domains of life:

– LED car tail lights can be a dangerous distraction on the highway at night.
– LED lighting in restaurants and other businesses can bother patrons, making them leave before they otherwise would.
– LED lighting in offices and schools can bother occupants, decreasing productivity.

I’m Lee Sonko and I have been investigating these issues for a few years. My stake in this is that I am bothered by this kind of lighting as well. By simply asking around, I have found many people whose quality of life has been degraded due to modern flickering LED lighting. There is research and guidance documents from the IEEE (Institute of Electrical and Electronics Engineers), the IES (Illuminating Engineering Society) and other organizations about this issue but there has not yet been the critical shift needed to change how industrial, commercial and residential lighting is built.

There are many possible paths to improving the lives of people affected by flickering LED lights. Most importantly, these issues can be identified and fixed with only a moderate amount of consideration and expense.

Work on this issue is ongoing and this site doesn’t cover everything that is happening in this field. If you’ve made it this far, I welcome you to contact me!

What’s going on in this video? Find out!


keywords: critical flicker frequency threshold, flicker fusion threshold, phantom array effect.

Note: I get my “5-10% of people are bothered by flickering” figure from casual empirical evidence. I have on many occasions asked a roomful of people if they are bothered by flickering lights in their environment. Invariably, about 1 in 15 people say that they are. In addition, there is evidence that some people are affected but don’t consciously realize it.