The Samsung Galaxy S21 smartphones have finally been officially unpacked. As expected, these Samsung flagships for the beginning of 2021 are packed to class-leading specifications. In the list of updated specifications, we also find the new and (claimed to be) much improved ultrasonic fingerprint reader on all three Galaxy S21 devices. Samsung claims that the new sensor is 1.7x larger than the previous generation. We recognize that this new ultrasonic fingerprint scanner on the Galaxy S21, Galaxy S21 Plus and Galaxy S21 Ultra improves biometric unlocking on these devices for reasons beyond just an increase in the scanning area.
Before examining how the Galaxy S21 series fingerprint reader is enhanced, let’s first discuss ultrasonic readers and how they differ from other screen fingerprint readers.
What is an ultrasonic fingerprint scanner?
The popularity of display fingerprint readers increased a few years ago with the economy – and therefore greater availability – OLED or AMOLED displays. Currently, there are two main types of fingerprint readers on display available on the market – optical and ultrasonic. Both types of optical fingerprint readers send signals of different types and record reflections. These reflections allow the sensors to create a reference image at the time of registration and later used for authentication.
As expected, optical fingerprint sensors use light, while ultrasonic sensors use pulsating ultrasonic sound waves to scan your finger. Since optical scanners can only form an image of the visible lines at your fingertips, they form a 2D image of your fingerprint. In contrast, ultrasonic sensors can create a three-dimensional image. Theoretically, this means that ultrasonic fingerprint scanners should be more reliable and even usable when your finger is wet or dirty.
However, this did not exactly work in favor of ultrasonic fingerprint readers, as expected. The ultrasonic scanner that has been available on Samsung’s flagships since the Galaxy S10 series has been slow and unreliable. Samsung tried to resolve these issues with a software update to improve unlock speeds and another to resolve the authentication flaw that allowed anyone to unlock devices. However, the new and updated fingerprint reader is designed to inherently fix these problems.
How is the Samsung Galaxy S21’s fingerprint reader better?
As we mentioned above, Samsung claims that the fingerprint scanner in the Galaxy S21 series is 1.7x larger than the previous generation, that is, the Qualcomm 3D Sonic sensor used by Samsung in previous devices, such as the Galaxy S10, Galaxy Note 10, Galaxy S20 and the Galaxy Note 20 series. Following the Galaxy Unpacked event, Qualcomm has officially confirmed that the Galaxy S21 series uses the recently announced Qualcomm 3D Sonic Sensor Gen 2 ultrasonic scanner.
In addition to a 77% larger surface area, the new Qualcomm ultrasonic sensor in the Galaxy S21 series offers 50% faster scanning. The new features will undoubtedly improve the unlock and security experience across the Galaxy S21, as well as other future devices that feature the same.
In real-life demos, like the one posted by Ben Schoon from 9to5Google, the new fingerprint reader appears to be very fast. We will be testing extensively while reviewing Galaxy S21 devices and also comparing them to older Samsung flagships. In the meantime, here’s the video Ben posted on Twitter after the Galaxy event:
The S21 fingerprint scanner is faster, but not better than the optical. Too early to talk about accuracy
Definitely a big improvement, although pic.twitter.com/iR9tHvpfl4
– Ben Schoon (@NexusBen) January 14, 2021
The Samsung Galaxy S21 Ultra is the ultimate hype in the new flagship 2021 series, packed in a flagship SoC, a premium build, a great screen and an amazing camera setup, as well as all the extras expected in a flagship premium.