Some people find black text on a bright white screen uncomfortable to read. Words may seem to blur, shimmer or move, lines run together, and reading becomes tiring after a short time. A coloured overlay or screen tint, which puts a wash of colour over the text, makes reading noticeably more comfortable for many of them.
What is visual stress?
Visual stress (sometimes called Meares-Irlen syndrome, or scotopic sensitivity) describes discomfort and perceptual distortions when reading, especially with high-contrast black-on-white text and patterned pages. It is often reported by people who are dyslexic or who experience migraine, but it also occurs on its own.
Research evidence on coloured overlays is mixed, and they are not a substitute for dyslexia support. However, many people report that a particular colour makes reading more comfortable, and there is little downside to trying. If reading is uncomfortable, it is a good idea to have a full eye examination first, because an uncorrected focusing or eye-coordination problem can cause similar symptoms. Some optometrists offer colorimetry assessments.
Paper overlays vs on-screen tints
Paper overlays are sheets of coloured plastic laid on a page. On a screen you do not need the plastic: software can tint the display directly, and it has advantages:
- Any colour and strength. You can fine-tune the hue and opacity rather than choosing from a handful of sheets.
- Only where you need it. You can tint just the part of the screen you are reading.
- Combined with magnification. A tinted, enlarged reading line is often more comfortable than either on its own.
- Always with you. Settings are saved and apply in every application.
How to use screen tints in Sensory Magnus
Sensory Magnus for Windows can apply two independent tints, with or without magnification:
- A tint on the reading area: the lens, ruler or whole screen. Choose yellow, blue, green, plum/rose, greyscale or inverted, or any colour from the colour wheel.
- A background tint for the area around the lens or ruler, with its own colour and opacity, placed above, below or both.
A ruler with a yellow tint on the reading line and a plum tint above and below, a combination some readers find comfortable.
Set magnification to 1× if you want the tint without any zoom. Step-by-step colour tinting help.
Finding your colour
- Try each colour for a few minutes with a real reading task, not just a glance.
- Start with a semi-transparent background tint (around 30–50% opacity) so the rest of the screen is calmer but still visible.
- Notice comfort, speed and how long you can read before tiring, and ask whether the text seems steadier.
- Your best colour for a screen may differ from your best paper overlay, because screens emit light.
- Reduce overall screen brightness too. A very bright screen can undo the benefit of a tint.
Other things that help
- Increase text size and line spacing, and use a clear sans-serif font.
- Use a reading ruler view so only one or two lines are highlighted.
- Listen as you read: text-to-speech with word highlighting reduces the load on your eyes. Sensory Readable, also from Sensory App House, provides reading support with speech.
- For printed pages, Magnus for iPhone offers 9 colour tints, contrast control and read-aloud through the camera.
Frequently asked questions
Do coloured overlays work on a computer screen?
Software tints work in the same way as a coloured overlay, but you can choose any colour and strength, and apply it only to the part of the screen you are reading. Sensory Magnus for Windows does this for free.
Which colour overlay is best?
There is no single best colour. People who benefit usually find one particular colour works for them, which is why it is worth trying several at different strengths.
Do coloured overlays help with dyslexia?
Not with dyslexia itself, and they are not a replacement for dyslexia support. They can make reading more comfortable for people who experience visual stress, which some dyslexic people do.