Shine Your Eyes: DIY Eye Test


A team at the non-profit LV Prasad Eye Institute (LVPEI) has developed an instrument that can

assess the severity of refractive errors of the eyes and help one decide when it is necessary to

see an eye doctor. With its innovative ‘Folding Phoropter’ design, the team has developed a

phoropter, an instrument used to test different lenses to assess the refractive errors of the eyes.

Photoropter is a common name for an ophthalmic testing device, also called a refractor. It is

commonly used by eye care professionals during an eye examination, and contains different

lenses used for refraction of the eye during sight testing, to measure a patient’s refractive error

and determine the eyeglass prescription. It also is used to measure the patients' phorias and

ductions, which are characteristics of binocularity. 

“The best part about the product is that anyone can assemble it easily. This gives the person a sense of ownership because he/she has assembled it,” says Ashish Jain, who heads the project.

The Foldable Phoropter was not invented to replace a doctor’s medical diagnosis and tell your lens specification, but to deduce whether a trip to the doctor is necessary. This in an extensive overview helps save money, time and stress.

The idea for the device was conceived at a hackathon called ‘Engineering the Eye,’ organised at BITS Hyderabad in 2013. Veerendranath Pesala, an optometrist at LVPEI, was mentoring one of the teams at the hackathon and the initial prototype for the phoropter was made from plastic. The model was further refined by an in-house innovation team at LVPEI.

Dhruv Joshi, Technical Head of the Innovation Center at LVPEI, suggested that instead of plastic the body of the instrument should be made of paper. The idea was inspired by a microscope developed by Stanford Professor Manu Prakash (  Professor of Bioengineering at Stanford University); he wanted to make the device out of paper to make it low cost and scalable so that it can reach to the mass. The current model has the look of an origami piece but the core of the design is the two lenses and the ability to slide them into positions along the rectangular body. It is a two-lens telescopic system.

 “The patient needs to look through the device a fixed distance away from the designated target, and move the outer chamber inwards until the image just comes into focus,” the LVPEI website explains.

This is an incredible idea; I have experienced firsthand how ridiculously expensive eye treatments are, so much so that it became a fallacy of generalization that everyone that wore glasses was rich. This invention has not only connected technology and people, it has also eased the stress of having to go all the way to the doctors for an eye issue that isn’t even worth the stress in the first place and best of all it is available to everyone without income restriction. This idea can be advanced; the Foldable Phoropter should be modified and equipped to send statistics and results from the eye test straight to a nearby eye clinic for further treatment and if required glasses are made ahead of time or on arrival of patients.