Otago Photoscreener

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3D printed open source vision screening for infants

Redeveloped 3D Printed Otago Photoscreener

This project aims to produce an easily 3d printed photoscreening device for infants. If vision defects are detected early, they can often be corrected with low-cost interventions. The Otago Photoscreener is a proven design that is well suited to this task. These prototypes will be distributed by partner organizations operating in developing countries, initially in the pacific islands.

The Otago photoscreener [1] detects refractive errors, squint (Strabismus) and lazy-eye (Amblyopia) in pre-verbal infants. This is the ideal time for intervention as the visual system is not fully developed and can adapt quickly. Limited data is available on the worldwide prevalence of these vision impairments, however the World Health Organisation estimated in 2004 that globally 153 million people are visually impaired as a result of uncorrected refractive errors. Strabismus and Amblyopia have been estimated to affect 1-5% of the population. This project will allow easy screening for these conditions and allow a significant reduction in visual defects amongst the most vulnerable members of these developing populations.

In addition the Otago photoscreener we have developed has been shown to be sensitive to cataracts. We are planning a study to quantify how well this performs.

Project Partners

Lions Eye Institute, Otago University.

Otago Photoscreener

Otago Photoscreener from 1983

The Otago Photoscreener is a medical optical instrument, developed to provide an indication of the fixing and focusing of a patient's eye with high sensitivity. First described in 1983[1], the Otago Photoscreener is a 35 mm single lens reflex camera with the flashlight coming from a narrow ring around the outer margin of the lens. Proven successful on children aged 5 to 6 months and older, the Otago Photoscreener is a quick and effective tool for the early detection of visual development problems such as strabismus, amblyopia and refractive errors.

Future Proofing

Based upon the proven concept and design of the original Otago Photoscreener, the Electronics Research Group has modernised the design and componentry selection to future proof the device.

The redevelopment of the Otago Photoscreener has allowed for easily sourced and standardised components to be utilised, with electronic components being specifically selected so they can be hand-soldered.


1. Molteno AC, et al. The Otago photoscreener, a method for the mass screening of infants to detect squint and refractive errors. Trans Ophthalmol Soc N Z 1983;43-9.