Eye Tracking: how does it work and what can it do?
Eye tracking still sounds clinically futuristic. Motion sensing technology has been widely commercialized in devices such as Wii Fit’s, FitBit’s and smart home motion detectors, yet eye tracking still screams ‘Back to the Future’ or ‘Scotland Yard’ for some reason – perhaps as a result of its portrayal in films.
Surprisingly, however, eye tracking technology is easily understandable and there is no reason why it cannot be integrated into everyday devices. In fact, unbeknownst to many of us, there are already a lot of eye tracking devices on the market – albeit with large price tags attached.
So how does eye tracking work?
The underlying concept behind eye tracking is ‘pupil center corneal reflection’ (PCCR) and it’s really rather straightforward: Near-infrared light is directed towards the center of the pupil (from an eye tracking device), causing visible reflections in the cornea (outer-most optical element of the eye). These reflections are then captured by a camera in the device, which in turn has the ability to trace the reflections back to their original light source (e.g. somewhere on a TV). Using data such as the angle between the cornea and pupil reflections, a vector is then mapped which near-enough pinpoints the exact gaze of the person.
How can eye tracking be used?
1) Research technology
For a number of years, eye tracking technology has predominantly been used for research purposes. In the medical industry it can be used for successful diagnoses of diseases like ADHD, Autism, OCD and Alzheimer’s. In terms of education it can help teachers to understand how students absorb and understand learning content and in the advertising industry it is used widely to monitor consumers’ responses to ads, helping to determine what best captures their attention.
As often seen in films about jet-set businessmen and secret detective agencies, eye tracking technology can be used to authenticate a persons’ identity. Rather like a fingerprint, an individuals’ iris is unique to them and them alone. This biometric technology has been proven to have remarkably low false match rates and has become popular over recent years in passport-free automated border-crossings.
3) Assistive technology
The possibilities of biometric technology are endless as there is no reason why it cannot be linked with other technologies. For example, many people who have impaired speech as a result of diseases like CP, Autism and ALS use eye tracking tablet devices that convert their gaze into spoken words. The user selects words, phrases and letters from their device using only their eyes and the machine then speaks them aloud.
In recent years, gaming device companies have begun to latch onto the potential of biometrics with eye monitoring gaming laptops and monitors. The devices are not yet in every gamer’s bedroom, but we predict that by the end of 2017 they will be. One such example is Acer’s brand new Predator gaming range. The monitors in this range, for example, allow the gamer to aim using only their eyes with natural targeting and make split-second shots with just a single glance. When their peripheral vision dims, the gamer must look towards the sun or into the shadows to readjust.
5) Automotive eye tracking
One of the leading causes of accidents and deaths whilst driving is tiredness. However, by attaching an eye tracking monitor to the dashboard, drivers can be alerted when their eyes are becoming overly tired, for example when their blink rate increases, and instructed to pull over. In the future this technology is expected become integrated into all automobiles and data from the biometric system may be stored internally and used by insurance companies in the event of crashes etc.