Can e-ink be a viable alternative to LCD screens?

It’s nearly impossible to avoid screens nowadays. This makes life difficult for the small but growing group of people that get debilitating symptoms when they look at screens for any amount of time.

Organizing on forums like the e-ink subreddit and LEDstrain, this community has been a wellspring of information about display technologies and eye health. They go further than the popular discourse in these areas, which usually centers around limiting screen time and how blue light disrupts our sleep.

It turns out that the only type of display that doesn’t trigger their symptoms are e-ink screens, which most people associate with the Amazon Kindle. E-ink differs from the ubiquitous LCD displays in that they don’t use a backlight to illuminate the display, instead relying on ambient light already found in the environment.

It’s not clear why e-ink screens don’t trigger symptoms beyond the fact that they’re not backlit. Research around the long-term health risks of extensive screen use is practically non-existent. To learn more, we’re left to lean on the personal experience of the screen-sensitive folks who have made the switch to e-ink.

Screen sensitivity

A reddit user shared his journey, which started with neck/occipital pain that appeared out of the blue at 33 years old. Previous to that, he had never had neck pain, led an active life, and was otherwise healthy.

Over the next few years, he worked with many types of doctors and tried various medications and therapies for the pain. Unfortunately, nothing was working so he took matters into his own hands by painstakingly testing and adapting every aspect of his life so that he could isolate the cause.

He eventually discovered that his issue was linked to the visual system. In one experiment, he went 48 hours without any screens and noticed that the pain came back instantly after he used a screen again. It was difficult to make this connection because the pain from LED screens took a long time to wear off.

He never got a good explanation from doctors as to why LED screens have this effect, but his personal theory is that it was caused by overuse of bright light therapy many years back. Nowadays, he makes a living only using e-ink screens that don’t trigger the pain.

This is a typical story. The symptoms either start out of the blue or gradually. Affected people usually have no issues with backlit displays until they find themselves unable to look at screens without serious discomfort or pain. If it weren’t for e-ink, many of them claim that they would have had to change careers.

Scarce scientific evidence

The reason for why these people develop screen sensitivity is unknown, but it’s clear that backlit displays are the cause and they’re more harmful for some than for others.

There’s no research on the long-term health risks of extensive screen use, with most studies focusing on short-term effects. One study compared the effects of different displays on the visual system found that prolonged reading on an LCD screen triggers higher visual fatigue than both E-ink and paper.

Another study suggested that reading on the two display types is very similar in terms of both measures of attention or visual strain. It’s hard to extrapolate much from these findings, due to small participant pools (10-12) as well as differences in device settings and ambient lighting conditions.

It’s one of those areas of research that isn’t taken seriously partly because it would be incredibly inconvenient if the findings suggested that the health risks of LCD screens were significant. The majority of the screens on any kind of consumer device are backlit displays, so the risks would be unavoidable.

Having a sustainable alternative to backlit displays in e-ink would not only help the screen sensitive community, but it would also change research incentives. It would impact the urgency and practicality of  large-scale comparative research on the effects of different display technologies on our visual health.

E-ink industry is ramping up

Compared to backlit screens, e-ink is much less disruptive for nighttime use, perfect visibility in the sun (no glare), and a battery life on the scale of weeks rather than days.

Unfortunately, the e-ink industry has never found mainstream consumer appeal beyond e-readers. The reMarkable tablet is probably the most successful e-ink computing device, recently crossing a million units sold. While this sounds impressive, it ultimately represents a tiny fraction of the overall tablet market.

The good news is that recent developments have enabled colored e-ink, which marks a watershed moment for the industry. After decades of obscurity, there’s a real possibility of a future where e-ink becomes a viable alternative to backlit displays.

This isn’t to say that e-ink will be able to compete as a general-purpose device, especially when it comes to entertainment (e.g. streaming, video games) or video conferencing. It’s more likely that e-ink will be adopted as a dedicated device for tasks where low power consumption is preferable to high resolution.

E-ink might be appealing for students, knowledge workers, and anyone else that spends hours a day reading and writing digitally. Having a separate device helps establish a routine and is much less prone to distraction. It also makes it much easier to work under the sun, which has plenty of second-order benefits.

More importantly, shifting hours of screen time from backlit displays to e-ink may be significant for our eye health in ways we don’t yet understand. Our future selves might be shocked to think back to when we used backlit displays for all of the various digital tasks in our lives.

Configuring backlit displays

E-ink displays are unfortunately not widely available today, so you might be wondering what steps you can take to limit the negative effects of the backlit displays you use daily.

The first step is to check whether you current display has these features:

• Flicker-free. Avoid monitors using screen flickering (PWM) to achieve lower brightness settings. This can cause eye strain and headaches, especially for those with screen sensitivity.
• Refresh rate. This is the frequency at which the image on the display is refreshed. Aim for at least 60 - 75Hz to reduce eye strain. Higher refresh rates (100Hz+) might have diminishing returns.
• Blue light filter. Newer displays tend to have settings that automatically adjust from cooler during the day to warmer colors after sunset, to make it easier on your eyes and reduce sleep disruption.

The single most important factor for eye strain is whether the light emitted from the backlit display is balanced with the ambient light in the environment.

A common scenario is looking at a bright phone screen at night after turning off the lights, which causes dry eyes and fatigue due to the light contrast. Most people intuitively lower the phone’s brightness to combat this, but it’s also important to turn on a dim light while you’re using your phone at night.

This principle also applies during the day. The brightness of your laptop or monitor display should adjust to the intensity of sunlight throughout the day. It’s easiest if the display does this automatically, but make sure to tune it so that the light emitted by the display is comparable to the ambient light around it.

The other side of the equation is the indoor lighting setup. Investing in quality lighting could be just as important as a quality display in terms of visual comfort. Most people have fairly dim lighting, which makes it so that the screen brightness is out of balance. This is especially noticeable in the winter, when the sun goes down earlier than usual. Check out this post for more about setting up your indoor lighting.