Modern tools that measure refraction and determine prescriptions are bulky and expensive. They also generally require the expertise of a trained professional. So although eyeglasses can be manufactured for as little as $.75 per pair of eyeglasses, there are still 2.4 billion people worldwide who require prescription glasses, but don’t have access to them because they don’t have access to the proper diagnostic tools/professionals.
With smart phones – the iPhone in particular – taking over more and more aspects of our lives, experts in every field are wondering how smart phones might revolutionize their world. In the world of optometry, is there going to be an iPhone app that will be able to prescribe glasses or contact lenses in the near future? For those without the resources for traditional eyecare, iPhone apps that could provide cheap, on-demand eye tests would offer a viable alternative to the traditional, bulky, and resource intensive prescription measuring devices currently being employed in the eyecare market.
Can the iPhone Be The Answer?
While there are a number of clever apps that can examine and take pictures of the eye, none of them have the capability to do refractions, which are necessary to measure prescriptions. The technical problem encountered by the iPhone is that – in order to do the necessary refractions – the iPhone camera would need to be able to shine a ringed pattern on to the eye, under strictly controlled conditions. This would be a problem for an iPhone based topography system that simply relied on the native iPhone camera to map the surface of the cornea. The iPhone – or any other smart phone or tablet for that matter – simply does not contain the native hardware necessary to produce lens refractions, or even accurate corneal topography.
Hardware Addons
With the native iPhone camera being unable to measure refractive errors and determe prescriptions, any lens prescription solution that leverages the iPhone’s widespread availability and processing would need additional, specialized hardware. That’s exactly what a company called EyeNetra is currently working on. EyeNetra is currently developing a diagnostic device that attaches to an iPhone and can quickly measure for nearsightedness, farsightedness, and even astigmatism.
Traditional automated solutions for estimating refractive correction use highly sensitive digital sensors, along with lasers and trained professionals. This makes the process very expensive, even to prescribe cheap, discount contact lenses or eyewear. EyeNetra’s high tech solution combines inexpensive optical elements with a high resolution programmable display, an interactive graphic user interface, as well as a computational reconstruction in order to offer accurate measurement of refractive errors, focal range, lens opacity, focusing speed, and a variety of other parameters that are currently expensive to obtain.
Will Optometrists Be Replaced By iPhones?
When the technology offered by companies like Eyenetra hits the commercial market, will optometrists be replaced by iPhone based prescription tools? The answer to that is no, optometrists are not going anywhere anytime soon. Eye doctors do significantly more than simply prescribe cheap contact lenses. A doctor must ensure that the lens fits the eye correctly, and that the patient’s tear film can handle contact lenses without irritation or damage. Additionally, there are other factors that could cause problems with contact lenses, such as how eyelids affect the lens. There may be subjective responses and reactions to a specific pair of contact lenses which will require experience and expertise in order to troubleshoot.
Because of this, any app/device combination that could accurately measure the curve of the cornea and refract the eye would likely only be useful as a preliminary diagnostic tool. It could potentially be used to prescribe a “trial” contract lens prescription for example, but long term fit and eye care requires more than simply measuring the degree of near/farsightedness. Even EyeNetra is working on a cloud platform that will allow their mobile phone eye diagnostics to be quickly sent to eye care providers. So while the prospect of obtaining a reliable prescription with a smart phone – at a remarkably low cost – is a likely possibility in the near future, we will still need experienced, well-trained eye care professionals assisting with prescriptions. There are too many other factors that go into fitting contact lenses or glasses that require the knowledge and experience of a professional.
This guest post was written by Endre Rex-Kiss, a green technology enthusiast. He is also an occasional guest blogger and freelance writer, this time writing for Lenses Online, a popular New Zealand based e-commerce site for cheap contact lenses. You can follow Endre’s rants on Twitter.