Tech Explained: Biometrics

Our latest Tech Explained helps you understand how biometric technology works to identify someone from their handprints, fingerprints, voice or iris.

If you have ever watched a modern spy movie, chances are at some point the hero will need to get past a security system operated using finger or hand prints, voice or iris print for confirmation. This is biometrics – technology that identifies a person based on physical or behavioural traits. Today, biometrics is not just the stuff of secret agents. Airports, hospitals, hotels, and even theme parks are increasingly using biometric security systems. Unlike keys and password-based systems, biometrics have the advantage that they are difficult to copy, and cannot be forgotten or misplaced.

Although biometrics may seem complicated, they all use the same components: a sensor to read and record information; a computer to store the information; and software to connect the hardware to the sensor. In addition, all biometric systems use the same steps. The first time someone uses a biometric system, it records their biometric data. The system then analyses the trait and translates it into code. Then, the next time that a person uses the system, it compares the trait against the stored information.

One common biometric system uses hand or facial geometry. This type of system uses a digital camera and light to take measurements of different points on a users’ hand or face. That information is then translated into a numerical template. Because hand and face geometry is not as unique as other traits, this type of biometric system is most often used for authentication, rather than identification. For example, some businesses use hand biometrics instead of timecards. At Springwise, we have seen facial recognition technology used in government and to identify endangered primates.

Fingerprint scanners work in a similar way to hand or face geometry, but are more accurate. The fingerprints are recorded either by taking a digital photograph, or using capacitive resistance. In this method, the scanner measures the distances between each part of the finger and the scanner surface. The scanner then uses this data to build up a picture of the fingerprint.

For higher-security applications, one option is voice biometrics. To enrol in a voice biometric system, users first give a sample of their speech. The words are then turned into a sound spectrogram. This is a graph with the frequency mapped against time. One advantage of voice biometrics is that it allows people to give authorisation without being physically present. However, these systems can be bypassed using a voice recording.

The most difficult biometric system to bypass is iris scanning. This uses visible and near-infrared light to take a high-contrast picture of an individual’s iris. The software then analyses the patterns in the iris and translates them into a code. Iris scanners are actually more precise than fingerprints, as they allow for more points of reference. For this reason, iris scanners are most commonly used in high-security applications. However, Springwise has also covered a startup that aims to bring iris scanning to personal devices.

As the technology for biometrics improves, we are likely to see it encompassed in a wider variety of uses. Although increased use may also raise serious concerns about privacy and security, biometrics are likely to be the ID card of the future. How will people protect their privacy while using biometric systems every day?