Have you got your finger on the pulse of biometric technology?
We all know about the uniqueness of fingerprints and how they don’t really change during a person’s lifetime (short of getting a cut or a burn). Technology has come a long way since the ink, paper and magnifying glass of the mid-19th Century. Nowadays, fingerprints aren’t only used in criminal investigations. There are national identification systems which utilise fingerprints in many countries around the world. Fingerprint recognition systems are available commercially; packaged with smartphones and tablets; and can be used to secure safety- or security-critical environments much more reliably than physical keys.
Fingerprint fact file
How do fingerprint scanners work?
Fingerprint scanners take “images” of a person’s fingerprints and generate a template based on a set of specific features (known as minutiae). The analysed templates are stored in a database. These templates cannot be used to generate the original fingerprints.
For verification, an “image” is taken again and analysed. This analysis is compared against all the records in the database to find the closest match within a predefined threshold.
The differences between each type of scanner centre around how they take the “images” in the first place.
Other types of fingerprint scanner not described here include thermal scanners and radio frequency scanners.
Touch and swipe scanners
Fingerprint scanners are also divided into touch and swipe scanners. A swipe scanner has a smaller contact surface which the finger is swiped over, whereas touch scanners just require the finger to be placed on the surface. In general, swipe scanners tend to require a bit more practice to use properly, but the swipe action does keep the surface clearer of latent prints and other contaminants. A drawback with touch scanners is that users can push their finger too hard against the scanner, which can distort the image taken or even damage the scanner.
Clearly the different costs involved, as well as security and reliability, affect which type of scanner is best suited to a particular situation. It would be impractical to use a clunky, expensive ultrasound scanner in a mobile phone! Likewise, it would be unacceptable to secure a nuclear power station with a simple optical scanner. When we work with construction companies, we lean towards using multispectral scanners as they’re fairly reliable and not to expensive. Construction workers are using their hands all the time, so it’s not uncommon for surface prints to be damaged or distorted, but the multispectral scanner allows for images to be taken which look past this.
