“The Ultrasonic fingerprint scanner shouldn’t be mistaken for an optical fingerprint sensor, which is yet another tech enabling under-display fingerprint readers”

Samsung took the world by storm recently with the launch of  Galaxy S10 series and Galaxy Fold. Needless to say, the Galaxy S10 family and Galaxy Fold hogged all the limelight at the Unpacked event and rightfully so. The high-end Galaxy S10 duo — Galaxy S10 and S10+ (first impressions mark a lot of firsts for the brand including the Infinity-O displays, HDR10+ certification and the under-display fingerprint scanner. The in-screen ultrasonic fingerprint sensor is not just the first for Samsung but also first of its kind in the world. I know many of you just jumped up in retort that this implementation for fingerprint scanners isn’t new. Allow me to explain.

What is an Ultrasonic fingerprint scanner?

GalaxyS10_Fingerprint scanner

The 3D Ultrasonic fingerprint scanner has been developed by Qualcomm and the Galaxy S10 and S10+ are the first in the world to ship with it. Numerous videos of the fingerprint scanner in action are already up on the Internet, like the one above. If you look closely at the GIF image, you will notice one stark difference. Unlike the optical FPS modules we have seen in the past, the one on the Galaxy S10 Duo doesn’t light up. This is because this tech doesn’t depend on the light reading but uses sound waves to register your digits. 

How does it work?

Samsung Galaxy S10+ 11

The 3D ultrasonic fingerprint scanner uses an extremely high-frequency ultrasonic sound to take the reading of your fingerprint. The module, which is integrated into one of the layers that comprise the display, is a combination of a transmitter and a receiver. When the fingerprint is touched against the glass, an ultrasonic pulse is transmitted. The receiver then maps the fingerprint by acknowledging the way the sound wave bounces back. This is capable of producing an accurate 3D map since sound waves bounce back differently depending upon the ridges, pores and vein, which are unique for each finger. Qualcomm claims that the sensor is powerful enough to get a reading 4mm deep, which is almost pore level. 

How is ultrasonic fingerprint better than its optical counterpart?

Samsung Galaxy S10 03

As we have mentioned above, the ultrasonic fingerprint sensor uses high-frequency sound waves to create a 3D map of the fingerprint, which is unique to each individual fingerprint. On the contrary, the optical fingerprint scanner, or for that matter even physical capacitive scanners, use light or electronic pulses to create a 2D blueprint of your finger. Therefore, the physical and optical fingerprint scanner are prone to be fooled by a high-resolution photo or scan of a fingertip. Further, the ultrasonic fingerprint scanner can work through dirt, grime, water or even oil since sound waves can travel through them all. Thanks to the IP68 rating of the Galaxy S10 and S10+, now you don’t have to worry about not being able to unlock with wet hands or even underwater. This isn’t the case with the optical scanners since dirt obstructs the sensor from getting an accurate read.

So, how safe is the ultrasonic fingerprint scanner?


As is the case with most security features, there are dedicated modules to safeguard the scanner. The 3D ultrasonic sensor features Cryptographic Accelerators, Key Provisioning Security, and a Trusted Execution Environment. In layman’s terms, all this prevents third-party applications from accessing the fingerprint data stored on the device. Moreover, Qualcomm has integrated the Fast Identity Online (FIDO) Alliance protocols, which facilitates the use of biometrics online for digital payments without transferring the data to the cloud or other servers, which are more prone to hacking. Needless to say, the new-age ultrasonic biometric is as secure as the conventional ones and could be used without any worry in the world.

Needless to say, with the ability to work through grime and producing accurate 3D images of the fingerprint, the ultrasonic fingerprint scanner seems the way forward. However, there have been reports that the module doesn’t work through a screen protector, if that’s indeed true, it will be a deal breaker for many. We will bring you the real-life usage experience soon in our extensive review, so stay tuned.