Biometric Smartphone Security: New OSRAM IR LEDs Announced for Iris Recognition

April 05, 2017 by Robin Mitchell

Biometric security comes standard for most smartphones. Can IR LEDs keep iris scanning a viable option?

Many smartphones now come standard with biometric security capabilities. Iris scanning is one such system but it needs major improvements in order to stay at the forefront of device security. IR LEDs may be the boost it needs.

Modern devices use a number of security measures to prevent unauthorized access, including passcodes and drawn patterns. But clever criminals can get around these. Besides the usual warnings about keeping your passcodes secret and unique, unsavory types can apparently still steal your phone's security code via thermal cameras.

So designers now often turn to security systems that utilize metrics that are truly unique to individuals: biometrics. Fingerprints and now even facial features can be used to unlock a device.

Iris scanners are another option for biometric security. They're not quite as popular as fingerprint scanners so far, but the introduction of further improvements to IR LEDs for iris scanning may change that.


Biometric Security Systems for Mobile Devices

As mentioned above, the major staple in biometric security is fingerprint verification. Some manufacturers of smartphones, such as Apple, have been integrating fingerprint authorization for years. That's a trend that seems likely to continue. Just last month, Apple was granted a(nother) patent for an ultrasonic fingerprint scanner.

Additionally, 3D scanners in new generations of smartphones may make facial recognition the security system of choice. However, facial recognition systems have serious room for improvement. Evidently, a photo of the phone's owner can be sufficient to fool the system into unlocking.

Meanwhile, there's a surprisingly long list of smartphones that already employ some form of iris scanning. Fujitsu was the first to produce iris recognition system for smartphones with their Arrows NX F-04G. That was almost two years ago. On the list of phones with iris-scanning capabilities are the Android Idol 3 model and the infamous Samsung Galaxy Note 7.


The Galaxy Note 7 came equipped with iris-scanning tech. (Not the most ringing of endorsements.) Image courtesy of Samsung.


So why don't all new smartphones come with iris recognition tech? The problem may lie with how iris-scanning tech actually works when in the hands of a consumer trying to unlock their phone. For example, Samsung is reportedly adding facial recognition to work in conjunction with their iris scanner because the iris scanner, alone, is too slow to satisfy consumers. It's also been suggested that the concept of iris scanning is simply too inconvenient in its present state. Like facial recognition systems, iris scanners have room for improvement. 

Which brings us to IR LEDs.


Improving Iris Recognition Tech: IR LEDs

In hopes of helping iris-scanning tech improve, OSRAM has announced 3rd-generation IR LEDs for iris recognition. The SFH 4787S is the successor to the 4780S LEDs (PDF) that were first used for iris recognition in smartphones.

One of the earliest problems smartphone iris recognition faced was the mounting of the IR LED. Artifacts such as lens flair and bright spots on the target (the user's eye) can throw off the algorithms used to identify the target. This is why it's important that the light emitted from the IR LED is angled in a specific direction. 

However, common IR LEDs needed to be mounted on PCBs in somewhat awkward positions to be effective. This awkwardness can translate to increased manufacturing complexity and price. To solve this problem, OSRAM's 2nd generation of LEDs were manufactured with lenses and angle changes so that the IR LED could be mounted on the PCB just like any other components are.


The new 3rd generation IR LEDs. Image courtesy of OSRAM


The current problem now facing iris recognition is the need to further remove artifacts by preventing gradual illumination. In simple terms, even if an IR LED is angled correctly at the user, the emitted light still fades gradually which superimposes artifacts. This is what the 3rd generation of OSRAM IR LEDs aim to solve by producing flat light whose intensity does not change over the target (i.e., LEDs that remove the light gradients). 

With these improvements, iris scanning may really find its place in the device security landscape.


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The reality is that future smartphones will likely embrace sensor fusion in order to employ multiple biometric systems for security. Like Samsung, many companies will likely consider combining systems such as iris recognition and face scanning. That future, however, is largely dependent on how reliable and convenient each security system can become in its own right.