Measuring the human eye pupil diameter can be a difficult task, especially in people with dark irides. The Dean Pupillometer is an infrared imaging device used to measure the size of the pupil, without affecting its size with visible light, whilst maintaining a clear view of the pupil. It has been validated to an accuracy of +/- 0.05mm with minimal inter-user variability.

Various uses are possible, for example testing prior to refractive surgery, subtle pupil disorders such as dilation lag in Horner’s syndrome, vermiform movements in Adie’s tonic pupil, and even ascertaining a mild relative afferent pupil defect.

A high resolution monitor provides 10x magnification, making measurements easy and quick. A video feed can be digitised and / or recorded as well as being viewed simultaneously on the dedicated monitor.