The in-screen fingerprint scanner on the Galaxy S10 may look just like the OnePlus 6T, but do not be fooled. Samsung's flagship Galaxy S10 and S10 Plus are the first mobile phones to use Qualcomm's ultrasonic fingerprint technology, which uses sound waves to read the printout.
This "3D Sonic Sensor" technology refers to ultrasound in a doctor's office by bouncing off sound waves from the skin. It captures your details through water, lotion and fat, at night or in bright daylight. Qualcomm also claims it's faster and much safer than the optical fingerprint sensor you've seen on other phones before. That's because the ultrasound scanner does a 3D capture of all the ridges and valleys of your skin compared to a 2D image (basically a photo) that captures an optical reader with light, not sound waves.
The debate between ultrasound and optical fingerprint scanners comes at a time when biometric security is on the rise. On-screen fingerprint readers are a hot trend in phone design because they take up no space on the front of the phone and feel less about than a sensor integrated into the power switch or the rear housing of the phone. This design fits well with the movement towards a screen with barely visible apertures.
"Security and biometrics have rapidly integrated into mobile platforms," said Alex Katouzian, Qualcomm's Senior Vice President of Mobile Technology, in December at Qulalcomm's annual Tech Summit in Hawaii. "This is the future of fingerprint technology."
The ultrasound fingerprint sensor built into the screen layers replaces iris scanning as the biometric sensor of choice, especially for the Galaxy S10 and S10 Plus. (The Galaxy S10E has a conventional capacitive fingerprint reader on the on / off switch.) Since the Galaxy S7 there is aperture scanning, so Samsung's departure from it is a surprise. According to rumors, Google could fold 3D face scanning into the next version of Android
For an animated explanation of how ultrasound fingerprint scanners work, you should also watch the video in this story. What You Should Know About the Ultrasonic Fingerprint Reader on the Galaxy S10 and S10 Plus Screen:
What is an Ultrasonic Fingerprint Sensor?
The Qualcomm-developed 3D Sonic Sensor Fingerprint Sensor uses sound waves (this is the "sonic" part) to "read" your fingerprint when you unlock your phone. The trend today is to embed this fingerprint sensor under the display so you can unlock the phone by placing your finger or thumb in the center of the screen (also referred to as an in-screen fingerprint reader), but this type of sensor could do it There is also the home button of a device. CNET has seen in 2015 a prototype of this ultrasonic sensor.
In this case, the ultrasonic sensor is integrated into one of the different layers that make up your phone's display. When you place your finger on the target area, touch the glass of your phone, not the sensor. However, her skin emits a tiny electrical impulse that activates the sensor and makes him do his thing. It has been sleeping, but by touching the phone you wake up the alarm clock.
How exactly does the ultrasonic sensor work?
When your electrical signal hits the sensor, it emits sound waves that bounce back onto your skin. The surface of your skin is not flat – your fingertip is a unique pattern of ridges and valleys, making fingerprints a useful form of identification. These ultrasonic waves bounce back onto the processor, which images your fingerprint based on the sound wave's pressure reading on your skin. In particular, different voltage levels are calculated based on your ridges and valleys.
In a simplified example, say that your ridges are a 1 and your valley a 0. The ultrasonic sensor module can map this data to a detail – a rich 3D image of your fingerprint. The sound waves may also detect your blood flow and reject a printout from a severed finger. It can not be deceived by false fingers or synthetic skin.
Ultrasonographic Fingerprint Reader Compared to the Optical Fingerprint Reader: How Does It Differ?
An optical fingerprint reader – such as the one operated by component maker Synaptics– jumps the light on the finger and back to the sensor, which reads the reading as a 2D image interpreted. It essentially takes a photo of your finger to determine the pattern of the hills and valleys. However, experts say this approach is easier to fool with a photo, a fingerprint transfer (for example, when someone has raised your impression), or a fingerprint of a prosthesis.
Qualcomm claims that his ultrasonic fingerprint sensor is strong enough to read 4 millimeters deep when the print is scanned. That's pore level. We have not tried the Galaxy S10 ultrasound fingerprint reader yet, so we can not say with certainty if this is correct. But it's a safe bet that everyone in the security community will test it to the limit.
How does ultrasound differ from a physical fingerprint reader?
If you place your finger on a glossy reader on the back, side, or home button of a phone, your fingerprint will be picked up by a capacitive fingerprint sensor. Yes, "capacitive" is the same term that applies to your phone's touchscreen, where your finger scans the amount of electrical charge so that the display recognizes exactly where you are.
This is the same case. Capacitors throughout the scanner detect the placement of your finger combs by measuring the electrical charge and then adjusting the pattern of these charges to your registered fingers.
What is the advantage of this feature over Face ID and other face sharing features?
Apple's Face ID uses a 30,000 infrared dot depth map to image your facial contours. Samsung used competing technology to scan your iris but removed it for the new phones. The Galaxy S10 phones use a third method, which is baked in Google Android. Essentially, a photo of your face is taken. Face ID and iris scanning are considered safe enough for mobile payments. However, the Face Detection option in Android Pie does not support mobile payments. It is there for convenience, but does not provide strong protection.
It is possible that Samsung had difficulty installing a front-face 3D scanner in time for the launch of the Galaxy S10. It's also possible that Samsung ties its fate to what Google supports to save money on an investment just months away. It would not be completely uncontroversial to believe that Samsung wanted to save a Face ID-like option for a version of the Galaxy Note 10 released in August.
Whatever the plan or the motivation, it's likely that the ultrasound The screen-fingerprint reader will last for several generations – especially if it's as fast, comfortable and secure as Qualcomm says.
Published: December 4, 2018.
Update : Feb. 21, 2019 at 10:01 am PT.