What are the cell phone screen fingerprint unlocking? What is the difference?

Since this year, more and more flagship phones have adopted screen fingerprint technology, and even some thousand dollar machines have begun to use it, such as OPPOK1, Meizu 16X and so on. But the screen fingerprint technology used by different phones is also different. From this year's point of view, the screen fingerprint recognition technology popular for full-screen phones has the following three main types: light-sensitive screen fingerprint recognition, pressure-sensitive (capacitive) screen fingerprint recognition and ultrasonic screen fingerprint recognition.

Of these, light-sensitive screen fingerprint recognition is the most common this year, with relatively the widest application, and the vast majority of screen fingerprint phones currently on the market are based on this under-screen fingerprint technology.

Optical, capacitive, ultrasonic under-screen fingerprint difference

1, light-sensitive screen fingerprint recognition:

Advantages: mature technology

Disadvantages: at present, only support for the OLED screen, the screen is easy to aging

Representative models: vivoNEX, vivoX23, OPPOR17/K1, Meizu 16/16X/ 16Plus, One Plus 6T, Honor Magic2, Lenovo Z5Pro, etc.

Light-sensing screen fingerprint identification technology is one of the most used solutions for under-screen fingerprint phones this year. It mainly relies on light reflection to detect fingerprint circuits, and since LCD screens are unable to self-illuminate, products that support optical under-screen fingerprint recognition currently use OLED screens.

The advantage of the optical under-screen fingerprint sensor is that it can avoid the interference of ambient light to the greatest extent possible, and has better stability in extreme environments. The shortcomings are mainly that the recognition rate is not high enough, in addition to long-term illumination of specific areas of the screen, OLED screens are prone to aging problems. In addition, because only suitable for OLED screen, the cost is relatively higher compared to LCD screen.

2, pressure-sensitive (capacitive) screen fingerprint recognition:

Advantages: support for OLED and LCD screens, relatively low cost, no need for self-illumination, more power saving

Disadvantages: the signal is easy to interfere with each other, need to be used by pressing

Representative models: Huawei Mate20Pro, Xiaomi 8 fingerprint screen version, Xiaomi 8 Transparent Exploration Edition

Capacitive fingerprint recognition should not be unfamiliar to everyone, before many non-screen fingerprint, front fingerprint unlocking phone are using this technology. In the popularity of screen fingerprint phone, capacitive screen fingerprint and derived from the pressure-sensitive screen fingerprint recognition, also belongs to the capacitive screen fingerprint technology, through the built-in high sensitivity pressure-sensitive sensors, just put your finger on the screen unlocking area, a slight pressure can be unlocked.

Because capacitive under-screen fingerprint recognition does not require the screen to be illuminated during the recognition process, it supports LCD screens and is relatively less expensive. However, since smartphone displays have a touch layer for identification and touch control, this may result in the problem of mutual interference between the touch signal and fingerprint recognition signal. In addition, it needs to be pressed to realize the unlock, the operation speed is not advantageous.

3, ultrasonic screen fingerprint recognition

Advantages: high recognition rate, support for in vivo detection, higher security

Disadvantages: low imaging quality, low yield

Representative model: Samsung S10 series (soon to be released)

Ultrasonic under-screen fingerprint recognition program has not yet been mass-produced, mainly driven by Qualcomm. From the current exposure, the upcoming Samsung S10 early next year will use the ultrasonic screen fingerprint program.

The advantage of ultrasonic under-screen fingerprint recognition is that it has strong penetration and high resistance to smudges. Even wet fingers can still be perfectly recognized. In addition, relying on the excellent penetration of ultrasonic waves, it also supports live detection. Because of the ability to obtain 3D fingerprint recognition images, the security is higher than other under-screen fingerprint recognition solutions.

However, ultrasonic under-screen fingerprint recognition also has many urgent problems. For example, the imaging quality is low, the technology is not mature enough, the production is low. At present, ultrasonic under-screen fingerprint recognition has not been widespread commercialization, is due to the above reasons, the technology still has a lot of room for improvement.

From the current point of view, light-sensitive screen technology is the most popular and widely used, while ultrasonic screen fingerprints are expected to usher in the popularization of the next year, pressure-sensitive screen fingerprints, currently used by relatively few manufacturers. It is worth mentioning that Apple does not have any screen fingerprint products this year, are replaced by 3D structured light face recognition, the use of which is also very convenient, especially in the future, 3D structured light can be perfectly hidden in the screen, is expected to replace the screen fingerprint technology.