Phone access has evolved beyond a PIN code or screen swipe. Fingerprint scanners? So last year. Retina scanning, as per the ZTE Grand S3? A step forward. But none are a patch on just how impressive Fujitsu's iris recognition technology is, as we experienced at this year's Mobile World Congress.

At present the technology has been wired into an additional module, here shown on top of a Fujitsu smartphone. But in the very near future the technology, which comprises an infrared scanner and front camera, will be embedded within devices.

It's the fastest example of any eye-based access we've seen to a device. Check out the setup, registration and live demo video below to see for yourselves.

Personal data, security and biometrics are a big subject in tech at the moment. Some will shun the idea as giving away too much personal data, opening up additional vulnerabilities, but Fujitsu claims the iris scan data is stored within the local device only, never the cloud.

So why iris scanning? From the age of two an iris doesn't change, whereas faces do. An iris, similar to a fingerprint, has distinct information in its texture, but unlike a fingertip is almost flat which makes it easier to read.

The infrared light in this instance works at around 20cm from the eyes (it could work further away, but more power would be needed, which would be to the detriment of battery life), is invisible to the naked eye, harmless and, because of the light frequency, will work in low-light conditions too. No need for a bright phone screen to illuminate the face.

Fujitsu claims only one in every 100,000 sign-ins will fail, which is considerably less than fingerprint scanners - where a wet or misplaced finger won't be any use at all. It doesn't just have to be used for signing into a phone either - individual apps, such as the gallery in the example video above, can be assigned too.

watch as fujitsu iris recognition tech unlocks smartphone at a glance literally video image 5
Pocket-lint

It's the sort of thing that looks like a contrived setup, so we got Fujitsu to let us go through the registration process ourselves. It's quick, easy and really effective - not once failing to sign-in for us. Handing the handset back to our man from Fujitsu and, now under our iris registration, his sign-in immediately failed, stating "Cannnot read iris" (sic). But there's always back-up PIN access should you want it.

A far-fetched future concept? Not at all. Iris recognition technology is imminent, arriving in product as soon as this year, but more likely 2016.

Beyond phones we could see this being rolled out in much larger business applications, from airport scanners to office access. Heck, even a hotel room sign-in to save you from those irksome moments when you're caught in your smalls outside without the keycard.