Some late night browsing led to discovering this page on the U.S. Department of Energy website: https://www.energy.gov/eere/ssl/flicker-basics
It’s worth a read, especially as an introductory piece for flicker in lighting. I found the last paragraph particularly interesting,
Flicker—we know how to measure it. We know that sometimes it can be causing medical problems. But what we don’t know is what the thresholds are for those different kinds of reactions. We need research to tell us what are these thresholds? What’s acceptable for what kind of population? If you’re designing the lighting for schools, and you know that perhaps one or two percent of the population of the school may be autistic children, we really don’t know what ranges of waveforms are going to be problematic for them, and which are not likely to have any effect at all. So although we’re moving towards having some set standards for different applications, we really don’t know the medical implications, and that’s where we need the most research right now.
Here is a document on LED lighting in schools: https://www.energy.gov/sites/default/files/2024-12/upgrading-led-schools_nov24.pdf . The flicker section is especially interesting.
Flicker is the constant fluctuation of light output from 0% to 100%. Virtually all humans perceive flicker when the frequency is 80 hertz (Hz) or lower; some can perceive it between 80 and 100 Hz and others can perceive it at frequencies into the thousands. Factors that could introduce flicker in an LED include the electrical supply, the LED driver, a dimming system, and – when using TLEDs – possibly the existing fluorescent ballast. The industry is working on a suitable metric for flicker. At this time, the best method for determining whether flicker is occurring and whether it is acceptable is to install the product and observe it. Sensitivity to flicker can vary from person to person so even if you do not observe flicker, others still might experience it.