Every time someone mentions eye strain on a forum, someone inevitably replies, “You don’t need bias lighting with OLED.” It has become the new flat earth argument of display discussions. It’s confidently wrong, endlessly repeated, and based on a complete misunderstanding of what bias lighting actually does.

It’s About the Human Visual System, Not the Display

Bias lighting has nothing to do with whether your screen can display true black. It’s about how your eyes adapt to light. When you view a bright object in a dark room, your pupils contract to handle the display’s brightness, but the surrounding darkness constantly pushes them to dilate again. That tug-of-war leads to fatigue, even if you don’t consciously notice it.

Some people like watching OLED in perfect darkness — or, as the millennials call it, raw-dogging. It sounds hardcore until your retinas tap out halfway through an episode of House of the Dragon.

A neutral, low-level backlight raises the overall adaptation level of your visual system. It stabilizes your perception of contrast and lets your eyes relax into a steady state. That’s physiology, not opinion. And if you find it distracting, it’s probably too bright — or maybe your wall of Funko Pops, model ships, and baseball trophies is what is actually distracting. 

Contrast Ratios vs. Human Limits

OLEDs can hit “infinite” contrast ratios, but that’s a spec sheet fantasy, not a human one. The eye’s contrast sensitivity maxes out long before a modern display’s does. Beyond that limit, the extra contrast doesn’t make the picture better. It just makes viewing less comfortable.

This is where concepts like eigengrau and veiling glare come in. Eigengrau is the dark gray you perceive in total darkness, proof that the visual system never sees absolute black. Veiling glare is the internal light scatter inside your eye that reduces perceived contrast. Bias lighting minimizes both effects by giving your eyes a stable reference point for black and midtone levels.

Close your eyes right now. What you see isn’t pitch black, it’s eigengrau. If you think that’s perfect black, your visual acuity might not be as sharp as you think.

It’s Also About Accommodations

Some people can watch in a dark room for hours without discomfort. Others can’t. That doesn’t make one group right. It just means humans vary. Younger viewers might shrug it off the same way they shrug off loud concerts without earplugs. People with more visual fatigue or sensitivity notice the effects sooner. Different bodies, different tolerances.

Even the Pros Use Bias Lighting

Here’s the part the “you don’t need bias lighting” crowd always leaves out. Most of the premium professional reference monitors used in mastering suites and color-grading environments today are OLED.

And guess what? Nearly every one of those studios uses bias lighting. Not as decoration, but because it’s part of a controlled, standardized viewing environment.

At MediaLight, about 80% of our MediaLight Mk2 v2 customers use OLED displays, and roughly half of our LX1 buyers do too. That’s not theory. That’s real-world adoption. If bias lighting were unnecessary for OLED, the people whose jobs depend on color accuracy and visual comfort wouldn’t be using it in the first place.

The Irony

What’s funny is that the same people who shout “You don’t need bias lighting for OLED” are often the ones posting a week later about headaches, image retention, or eyestrain. The human eye doesn’t care what panel technology you’re using. It only knows how hard it’s working to adapt.

Bias Lighting Isn’t About “Needing” It — It’s About Doing It Right

A properly implemented bias light isn’t there to fix the display. It’s there to make you a more comfortable and consistent observer. The moment you understand that, the “OLED doesn’t need bias lighting” line collapses on itself.

Because this isn’t a display technology issue. It’s a human interface issue.

Reality Check

If you still think OLEDs are immune to eye strain, image retention, or headaches, try a simple experiment. Google it. You’ll find pages of results: ophthalmologists, display engineers, and real users all reporting the same thing. Display tech has advanced, but human vision hasn’t. Comfort still depends on managing contrast, flicker, and adaptation, not on marketing terms like “infinite black.”

That’s why bias lighting isn’t some outdated accessory. It’s the most overlooked part of a well-designed visual environment. Whether your display is OLED, LCD, or whatever comes next, your eyes still live in the real world.