Diagnosis and Treatment

Testing for this condition can only be carried out by a certified Irlen Diagnostician or Irlen Screener.

The Irlen assessment is a two step process involving:

(a) Diagnostic Session - Irlen Screening
(b) Treatment Session - Irlen Lens Tint Assessment

(a) Diagnostic Session – Irlen Screening

The first session involves completing the Irlen Reading Perceptual Scale (IRPS). This assessment measures the level of visual perceptual difficulty and/or discomfort when looking at black patterns and text on a white background. Irlen Spectral Filter coloured overlays are introduced to determine if a particular coloured overlay relieves the visual perceptual difficulty or discomfort.

This test determines whether a person has Irlen Syndrome and can be helped by Irlen colour technology. This session will establish if Irlen Spectral Filter Lenses will be required to eliminate or reduce significantly a person’s visual perception difficulties.

(b) Treatment Session – Irlen Lens Tint Assessment

The second session is for those who show moderate to significant improvement with Irlen coloured overlays. In this session, the precise Irlen Spectral Filter tint required will be chosen, to be worn as glasses or contact lenses. We target the specific wave lengths of light which contribute to a person’s Irlen symptoms and perceptual difficulties. The precise tint will not be the same as the Irlen overlay colour as there are a limitless number of Irlen tints available to be worn as glasses.


Testing to identify your correct Irlen Spectral Filter tint can only be conducted by Certified Irlen Diagnosticians. Coloured lenses provided by optometrists and vision specialists to treat reading and perceptual problems are NOT the same as Irlen Spectral Filters, and are not appropriate for this condition. These professionals do not have the necessary diagnostic training to complete the Irlen Spectral Filter lens tint process. Inaccurate tint selection can result in fragmented brain processing causing headaches, eye strain, further reading difficulties and increased perceptual distortions.