Flicker – The unseen, but seen, enemy
Flicker is technically, and boringly, described as “temporal variation in light output from a light source”. For the layman, that lights dimming up and down very quickly.
The problem with flicker is that in large doses, it causes some health problems, and the vast majority of LED lamps and most cheap LED light fitting have excessive flicker. Filter Circuits reduce the flicker to insignificant, but filter circuits cost money, and “filter circuits” don’t feature highly in marketing materials. Prioritizing low cost means that anything that doesn’t feature in advertisements gets discarded first.
Indiscernible flicker has been heavily researched, starting in the 1980’s, when the mass adoption of fluorescent lighting resulted in a significant loss of productivity in company employees.
It was discovered that the flicker from early generation fluorescent lights caused health issues in employees and increased absenteeism (that’s chucking sickies).
Low frequency flicker (between 0.5 and 100 times per second) is has been proven to trigger eyestrain, migraines, vertigo, anxiety, depression, epileptic episodes and general reduction in productivity. There is also some evidence linking flicker to triggering autistic behavior.
For your home, it’s worth avoiding all the issues that we learned about, the hard way, in the 1980s with the fluorescent lighting fiasco and its contribution to “Sick Building Syndrome”.
Good lighting is worth the money, even before evaluating “Total Cost of Ownership”.