The $15 Investment That Could Save Your Developer Eyes in 2025 (And It's Not Another Blue Light Filter)

Install a bias light.

Hi friends,

This week I want to share a simple idea that came to me when I spent some money on my office renovation: light.

I know as a software engineer I sound a bit too abstract, but I promise this will be less of an abstraction than an Event­Singleton­List­Broadcaster­Comparator.

But it has been a month since that article, why I didn’t write about this back then?

Have you ever felt sick and decided to address the underlying issue while you were sick, but once you got better, you just didn’t do it?

In psychology, this is sometimes called the fading effect bias, where negative feelings associated with being sick fade faster than positive feelings, making the need for preventive action seem less urgent once we're healthy again.

Eye strain needs no introduction to any of you.

Fortunately or not, it passes too quickly to be taken seriously. For me, though, when it’s paired with a migraine, I have to take a day off.

But we simply spend too much time looking at screens. Sometimes, what we do is also our hobby, so we end up looking at screens even more.

The final push for me to address this permanently was our HR software reminding me that I have three age-related days off—a nice way of saying, “You’re getting older.”

I figured, the sooner you reduce the stress on your eyes, the longer you’ll reap the benefits.

One way to reduce eye strain is to look at screens less, but let’s be honest—none of us are likely to do that.

So, what’s the next best thing?

The solution turns out to be surprisingly simple and cheap.

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But first, let’s address the elephant in the room.

Why Work in The Dark?

“Focus.”

We associate darkness with fewer distractions and noises.

But darkness also leads to more eye strain and fatigue.

The image of software engineers working in a pitch-dark room, with only the screen as a light source, is romanticized for no reason—and it’s terrible for your eyes.

Tom is a web developer and his eyes hurt every day.

Studies indicate that the contrast between a bright screen and a dark environment forces the eyes to work harder to adjust, which may lead to discomfort, headaches, and temporary blurred vision. Lighting Research Center, Rensselaer Polytechnic Institute. "New Study Tests The Effects Of Watching TV In A Dark Room." 25 April 2006.

The American Academy of Ophthalmology notes that maintaining balanced ambient lighting can alleviate this by reducing the stark contrast your eyes must adapt to when switching focus between the screen and surroundings.

But what if I told you that you could still work at night without hurting your eyes?

Enter the hero of today’s story: light. More specifically, bias lighting.

Bias lighting helps reduce eye strain by adding a soft, neutral light around the screen. It also improves the way we perceive contrast in the picture–because I’m assuming you’re not intentionally harming yourself and already have at least one light source besides your monitor.

Bias Lighting

If you’ve seen the pictures from my previous article, you know I work in a very bright room. I try to avoid working early in the morning when it’s still dark (though that’s when I write), and in the evening (sometimes impossible, since that’s when I do freelance work).

Working in a dark room with only the monitor glowing is one of my defining memories from my early college and work days.

Now, it literally hurts.

Luckily, the fix is around $15.

LED backlight tapes, mounted behind monitors, help reduce eye strain by providing ambient or "bias" lighting that improves visual contrast and reduces glare. By lighting up the wall behind the screen, they create a soft glow that lessens the stark contrast between the bright screen and a dark room, which is a common cause of eye strain.

Using bias lighting can reduce perceived screen brightness by 60-90% without changing the actual screen settings, making it easier on the eyes. (I found this figure in multiple sources, but no studies—maybe it's difficult to measure?)

This gentle background illumination helps stabilize pupil size, reducing fatigue during prolonged screen use, and creating a more balanced viewing experience.

How to Pick the Right Bias Light

Lights have a color temperature and it’s measured on the Kelvin scale.

• Lower Color Temperatures

  • 1,900K: Candle flame; very warm, reddish/yellow light.

  • 2,800K: Standard incandescent bulbs; warm light.

• Higher Color Temperatures

  • 5,000-6,500K: "Cool White" or "Daylight" bulbs; cooler, blue-toned light.

Lower values = warmer (red/yellow), Higher values = cooler (blue).

If you want to get the most out of your bias light setup, aim for a color temperature of 6500K.

Why 6500K?

The bulbs (be they CFL or LED) inside your HDTV or monitor are calibrated to 6500K. The film and digital video is color corrected to have a 6500K white reference point. The editing suites where content is edited and worked on have 6500K bias lights. Regardless of whether you use a fluorescent tube light, a strip of LEDs, or an incandescent light bulb, you want one with as close to a 6500K color temperature as you can get if your goal is to maximize the quality of the on-screen image. – https://www.howtogeek.com/213464/how-to-decrease-eye-fatigue-while-watching-tv-and-gaming-with-bias-lighting/

A product on Amazon with the right temperature LED stripe.

A lifetime investment for just a couple of dollars!

I’m curious to know if you’re interested in these ‘behind the scenes’ stories, as both this and my home office setup were fun to create. I love reading research papers, and the fact that these might positively impact your living conditions is a huge motivation for me! 😊

Let me know what you think in the comments!

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