Coloured filters are designed to help individuals who suffer from a condition known as visual stress. People with this condition are especially sensitive to lights, glare, patterns, colours, and contrast.
Coloured filters are designed to block the specific wavelengths of light to which an individual is sensitive. So, for example, an individual might be especially sensitive to blue light and therefore use a blue filter to reduce its effects.
There are several types of coloured filters including overlays and lenses. Coloured overlays are clear plastic sheets that can be placed on top of reading materials, such as books or newspapers. Coloured lenses are tinted, non-optical lenses which can be put into spectacle frames.
Some people believe that coloured filters can be used to help people on the autism spectrum who suffer from visual stress, leading to improvement in their visuospatial abilities. This may in turn lead to improvements in other areas, such as reading ability.
There is no research evidence to suggest that coloured lenses provide any kind of benefit for people on the autism spectrum.
There is some very limited, low quality research evidence to suggest that coloured overlays could be useful for some children and young people on the autism spectrum with a range of problems including difficulties with reading and recognition of emotions in other people.
Small-scale, pilot trials of the effects of coloured filters could be carried out on individuals on the autism spectrum to determine their effectiveness and safety.
If you have any concerns about your eyesight, or the eyesight of someone else that you care for, you should consult an optometrist in case there are any vision problems that have not been recognised.
Please read our Disclaimer on Autism Interventions