The Galaxy S21’s new Qualcomm fingerprint scanner should finally fix the problems with the last-gen

The Galaxy S21’s new Qualcomm fingerprint scanner should finally fix the problems with the last-gen

The Samsung Galaxy S21 flagship smartphones have finally been unpacked officially. As expected, these Samsung flagships for early 2021 are packed with class-leading specifications. On the list of the upgraded specifications, we also find the new and (claimed to be) much improved ultrasonic in-display fingerprint scanner on all three of the Galaxy S21 devices. Samsung says the new sensor is 1.7x larger than the previous generation. We reckon that this new ultrasonic fingerprint scanner on the Galaxy S21, Galaxy S21 Plus, and the Galaxy S21 Ultra improves biometric unlocking on these devices for reasons beyond just an increase in the scanning area.


Before we go over how the Galaxy S21 series’s fingerprint scanner is improved, let us first discuss ultrasonic scanners and how they differ from other in-display fingerprint scanners.

What is an ultrasonic fingerprint scanner?

The popularity of in-display fingerprint scanners picked up a couple of years ago with the economization — and therefore, wider availability — of OLED or AMOLED displays. There are currently two major types of in-display fingerprint scanners available in the market — optical and ultrasonic. Both kinds of optical fingerprint scanners send signals of different sorts and record the reflections. These reflections enable the sensors to create a reference image at the time of registration and later used for authentication.

As expected, optical fingerprint sensors use light whereas ultrasonic sensors utilize pulsating ultrasonic sound waves to scan your finger. As optical scanners can only form an image of the visible lines on your fingertips, they form a 2D image of your fingerprint. In contrast, ultrasonic sensors can create a three-dimensional image. Theoretically, this means ultrasonic fingerprint scanners are expected to be more reliable, and even usable when your finger is wet or dirty.

However, this hasn’t exactly panned out in favor of ultrasonic fingerprint scanners as expected. The ultrasonic scanner that has been available on Samsung flagships since the Galaxy S10 series have been slow and unreliable. Samsung has tried to address these issues with a software update to improve unlock speeds and another one to address the authentication flaw that allowed anyone to unlock devices. However, the new and updated fingerprint scanner is designed to fix these issues inherently.

How is Samsung Galaxy S21’s fingerprint scanner better?

As we mentioned above, Samsung claims that the fingerprint scanner on the Galaxy S21 series is 1.7x larger than the previous generation i.e. Qualcomm 3D Sonic Sensor employed by Samsung on previous devices such as the Galaxy S10, Galaxy Note 10, Galaxy S20, and the Galaxy Note 20 series. Following the Galaxy Unpacked Event, Qualcomm officially confirmed that the Galaxy S21 series uses the very recently announced Qualcomm’s 3D Sonic Sensor Gen 2 ultrasonic fingerprint scanner.

Qualcomm 3D Sonic Sensor Gen 2 featured

In addition to a 77% larger surface area, the new Qualcomm ultrasonic sensor on the Galaxy S21 series is claimed to offers 50% faster scanning. The new features will inarguably improve the unlocking experience and security across all Galaxy S21 as well as other upcoming devices that feature the same.

In real-life demos, just like the one posted by Ben Schoon of 9to5Google, the new fingerprint scanner appears to be really snappy. We will be testing it out extensively while reviewing the Galaxy S21 devices and also comparing it with older Samsung flagships. In the meantime, here’s the video Ben posted on Twitter after the Galaxy event:

    The Samsung Galaxy S21 Ultra is the ultimate overkill in the new 2021 flagship series, packing in a flagship SoC, a premium build, a great display, and an amazing camera setup, as well as all the extras expected on a premium flagship.

About author

Tushar Mehta
Tushar Mehta

I am a Senior Editor at XDA. I have been reviewing gadgets for over five years and gained experience by working for prominent tech publications in India before joining XDA. I enjoy fiddling with all smart objects and my love for software customization dates back to the Symbian S60 days. I like to devote my spare time idealizing the romantic union of technology and philosophy or spacing out on Pink Floyd. You may email me at [email protected]

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