Dyslexia

Black Paper

On Slashdot, a very popular geek site about the internet, Star Wars and all things nerdish, someone posted a question.

What font color and what background is best for the eyes, when you work for a long time? I have found various contradictory recommendations and I wonder if you know about any medical studies on this topic.

In amongst the almost 300 replies, most of which are just pure rubish, I found this comment by user unfunk:

When I was in uni, I used to buy special black paper “visual arts diaries” and write my class notes using a gold, silver, bronze, or plain white ink pen. This had the effect of making my pretty poor handwriting easier to read for most people, and also reducing the effects of my dyslexia; I would make less errors like inverting a series of numbers as I wrote them down and the like.

I’ve never heard of this approach. Has anyone else experimented with light pens on black paper to help with handwriting?

If you are interested in what font color / background to use on your monitor, then check out this answer by Skapare. His (hers?) comments on fluorescent lights, common in schools, is quite interesting.

Incandescent light has a fairly even level through all light wavelengths. This makes those black on white edges a bit fuzzy. But fluorescent light has two narrowband peaks at a red and green wavelength (the blue is broader). This can make the text edge sharper … twice. The eye ends up with two contrast edges. I believe this increases the eyestrain by causing the focus to be constantly jumping in and out to alternate the focus on the two different edges. It’s a very small adjustment, but it is there at least for me. With incandescent light, it just settles in the middle of the fuzzy range and doesn’t change much. And this is affected by how much light there is, which dictates how small the iris becomes. Higher light levels with a smaller iris won’t change the effect from fluorescent as much as for incandescent, since with fluorescent the two contrast edges are already rather sharp due to the two narrowband spectral peaks. But for incandescent, the high light level helps (up to the point that intensity is too stressful).