I've asked the LLMs this and they've given me conflicting answers. What they all seem to agree on though is that the combination that is best for legibility isn't the best for eye strain. I'm specifically interested in what causes the least eye strain. I did a superficial Google Scholar search and there's a few studies, but they seem to focus on legibility.

6 minutes ago, Stephen001 said:

I've asked the LLMs this and they've given me conflicting answers. What they all seem to agree on though is that the combination that is best for legibility isn't the best for eye strain. I'm specifically interested in what causes the least eye strain. I did a superficial Google Scholar search and there's a few studies, but they seem to focus on legibility.

I remember asking at school why Cambridge university exam papers were printed black text on light green paper and being told or reading that they had done a study which found that this particular colour resulted in the least number of candidates having some sort of panic/breakdown upon opening the paper in an exam.

Back in the day, Wordperfect 5.1 for DOS defaulted to white text on a blue background.

The claim was that we tend to see blue as "more distant", so this combination gave the least eye strain.

There is a lot of contradicting information in lit, and it mostly depends on what you measure. The few things where most studies agree is that digital reading is different from paper, so lessons are not easily transferable.

There are some studies on screen use, but the papers cover a lot of ground and include e.g. simulating driving and measures other than fatigue. A recent study has combined ambient lighting mode with screen color temperature and dark vs light mode. Generally speaking, they found that indicators of fatigue were higher when reading in light mode and with screen color temps in the lower (warmer) range.

Other studies have looked at alertness and onscreen tasks it seemed that blue was advantageous for folks to find stuff effectively. Whether that plays into fatigue was not tested.

2 hours ago, CharonY said:

There is a lot of contradicting information in lit, and it mostly depends on what you measure. The few things where most studies agree is that digital reading is different from paper, so lessons are not easily transferable.

There are some studies on screen use, but the papers cover a lot of ground and include e.g. simulating driving and measures other than fatigue. A recent study has combined ambient lighting mode with screen color temperature and dark vs light mode. Generally speaking, they found that indicators of fatigue were higher when reading in light mode and with screen color temps in the lower (warmer) range.

Other studies have looked at alertness and onscreen tasks it seemed that blue was advantageous for folks to find stuff effectively. Whether that plays into fatigue was not tested.

Anecdotally, sample one, high temperature light is great looking for stuff or at small details, but it keeps me awake at night. I consciously choose lower temps at night to tire my eyes and brain out. I think that might be due to the increased effort the brain and/or eyes undergo trying to chromatically recorrect the warm light to neutral white. I have a mix of 3000K, 4000K, 5000K, 6000K torches that I've played around with.

Edited Tuesday at 09:14 PM1 day by StringJunky

We find our 2700 K lamps relaxing in the evening. It decreases the melatonin suppression that comes with bluer light, provided that screens are also set to night mode. The lower kelvins also mimic natural evening light, like sunsets and fires, so that helps the circadian rhythms.

I find that text size is a big issue. But the OP asked specifically about color, so here’s a study but it’s specifically about “negative polarity” i.e. light text on dark background, which is “night mode”

The paper points out fatigue can come from bright screens in a dark environment, so matching brightness levels is important.

https://pmc.ncbi.nlm.nih.gov/articles/PMC11175232/

One might search further using “visual fatigue” and “polarity” as keywords