Why Touching a Fingerprint Reader is Still the Best Method of Biometric Identification

There has been some talk recently that the COVID-19 outbreak will spell the end for biometric devices that require contact. This is based on the premise that people will be hesitant to touch a surface that any other member of the public has previously come into contact with. The rumor goes that contact-based fingerprint scanners are heading to the scrap heap within two to three years. You can understand why these predictions are being made, but there are a number of factors which mean that this is unlikely to happen for some considerable time to come.

Let’s look at the contactless biometric identification methods which might support such a shift in our industry. The primary technologies are facial recognition, contactless fingerprint capture and stand-off iris. There are, of course, others such as voice recognition and gait detection which are interesting but less developed at this point. Facial recognition is currently the fastest growing biometric type, mainly for its convenience and compatibility with mobile devices.

Contactless fingerprint capture is becoming increasingly common for certain applications. This will continue to grow as many cameras inside mobile phones have reached such a high level of quality that they are able to capture a fingerprint image, so that applications utilising this technology are now coming to the market.

Finally, stand-off iris allows authentication from a distance, allowing for free flow of individuals in a similar way to facial recognition. With at least three technologies expanding the biometrics market, the predicted demise of contact technologies is rather premature.

In addition, mitigation techniques can be used to protect the public. Sanitation and hygiene regimes can be implemented to maintain the biometric devices and keep the active surface clean. These regimes are particularly applicable where there is generally lower throughput, for example in criminal booking or enrolment in government schemes.

Legislation and legal acceptance pose another considerable barrier to the adoption of contactless technologies in the relatively short timescales predicted. Facial recognition has been banned by some authorities over concerns relating to the individual’s privacy. While there is considerable work going on to modify legislation and address concerns, it is highly unlikely that these can be achieved quickly. In some jurisdictions, only contact-based fingerprint systems are recognized by the authorities as admissible in criminal cases. There will need to be a considerable effort made to evaluate, approve and certify new technologies, not to mention the time to lobby government, change and approve legislation. Contactless solutions which meet these requirements have been predicted for several years but very few actually exist.

The next consideration has to be quality. The quality of fingerprint biometric images is lower for contactless solutions compared to equivalent contact devices. It is also very likely that images captured using contactless technologies will be more difficult to match. In fact, high quality contact devices have shown a significantly better equal error rate when compared to contactless technologies. But quality must also be evaluated against the use case. For criminal booking and investigation, the highest quality fingerprints must be captured, as legal cases — and potentially the freedom of an individual — depend upon the forensic evidence. For authentication like building access, contactless technologies can give an acceptable error rate, provided that original enrollment came from a high-quality contact device. Quality is also an issue for contactless iris compared to the systems which capture the image through a goggle-like device. Despite the use of expensive, high-quality cameras, the stand-off versions tend to produce lower definition images which result in high levels of error when matching.

We should also not underestimate general complacency and acceptance. Once the restrictions on daily life are lifted, people will soon revert to old habits and quickly forget the issues associated with hygiene and transmission. Undoubtedly, there will be a permanent change in society, but to a level where people refuse to touch things? That seems unlikely. If that is the case there will be many more things to consider before biometric readers, such as doors, escalators, ATMs, etc.

Contactless technology will surely benefit from the fall out of the current pandemic. But then, contactless technologies were already progressing for certain use cases. Will that spell the end for contact biometrics? Unlikely. There will still be demands for high-quality fingerprints and iris capture at enrollment for many years to come, as enrollment processes form the foundations of all good identity programs, and the success of subsequent authentications is predicated on the existence of high-quality images captured in those processes. The one certainty is that the use of biometrics in everyday life will continue to grow, as the public becomes more accepting and legislation continues to evolve.

To learn more about why capturing a fingerprint can be a challenge and what technologies help you be successful, read our white paper “Higher Quality Fingerprint Collection with Silicone Membranes”.