Harris Filters

Making reading easier

Harris Filters can increase reading fluency, speed and can broaden the understanding of written text, helping people to enjoy and improve their quality of life.

They are effective in the treatment of Visual Perceptual Distortions also know as Mears-Irlen Syndrome, Visual Stress or Scotopic Sensitivity Syndrome.

Harris Filters are an advanced version of David Harris' award winning range of special lenses which can significantly ease reading difficulties in most dyslexics, with many people experiencing dramatic improvements. The filter technology is now widely accepted throughout the world and is used by thousands of people in the UK and USA alone.

Individually prescribed by a specialist practitioner and incorporated into almost any style of frame, many people have gained improvements in handwriting, spelling, coordination and self esteem.

People with dyslexia may have poor timing, be clumsy and uncoordinated, have difficulties identifying letters and words bringing poor self esteem, lack of confidence and frustration.

Some of the difficulties they may experience include;

  • reversed letters or words                                                                
  • poor tracking ability
  • dislike of reading - especially out loud
  • slow, hesitant, or broken reading that lacks fluency
  • print and text distortion


Harris Filter lenses work by changing the way in which the eye transmits messages to the brain via the Magnocellular pathway helping to overcome many variations of dyslexia.

Most patients describe text as becoming immediately clearer and easier to read with Harris Filters in place.