Qualcomm’s fingerprint scanner: an echo from the future

How many people with an iPhone 5s or iPhone 6 use the Touch ID fingerprint scanner in the Home button? Probably a high percentage. That has good reasons; it is an easy and fast way of security.

Nevertheless, there are areas for improvement. For example, it does not work well with wet fingers, which is inconvenient when it rains. You can also copy a fingerprint and gain access to someone’s device. Not that it’s a huge risk, but you’d rather rule it out.

Qualcomm says it has solved those problems with a new fingerprint scanner, which it makes under the name Sense ID. To do this, the company uses the same principle that obstetricians use when trying to see a fetus in pregnant women: ultrasound.

The idea of ​​a fingerprint scanner with ultrasonic sound is of course not new. You can get them for less than a hundred euros at the Alibaba auction site, but Qualcomm is a company that supplies a lot of technology for smartphones, partly because so many manufacturers use socs from the American company. This means there is a good chance that devices will really get this fingerprint scanner.

The big difference with current fingerprint scanners in smartphones is the way the system maps the finger. Touch ID and other current smartphone systems work with capacitive touch to map the fingerprint, a variation on the way touchscreens work on smartphones. That is based on a 2D image of the fingerprint, so it can be fooled.

Qualcomm’s Sense ID works with ultrasonic sound, high-frequency waves, that bounce off and under the skin so that the sensor picks up the reflections and Sense ID can capture the fingerprint in detail and in 3D. To fool this method, you need a 3d image of the finger. Dirt or moisture does not hinder the scanner. Sense ID works even better if the finger is moist, according to Qualcomm.

There was a limited test setup at the Mobile World Congress. Prototypes had the scanner as a module under a test phone. It turned out that it was not possible to unlock a phone. It was possible to view the live image, but in 2d.

The scanner indeed turned out to function slightly better with a wet finger and could not be upset by dirt on the finger. It is necessary to put your finger on the scanner.

Because the scanner works with ultrasonic sound, it also functions through metal and glass. As a result, it can be built into a phone anywhere, with almost any design. Qualcomm hopes to be able to integrate the scanner into a screen at a later stage.

Sense ID should appear in smartphones in the second half of this year. Qualcomm does not want to say who will apply the technology; it does want to say that these are ‘well-known’ manufacturers. It will be interesting to see what effect the scanner will have in daily practice.