How Fingerprint Scanners Work: Optical, Capacitive & Ultrasonic

How Fingerprint Scanners Work: Optical, Capacitive & Ultrasonic

Fingerprint touch sensors are of generally of three types, which are as follows.

  1. Optical Fingerprint Scanner

  2. Capacitive Fingerprint Scanner

  3. Ultrasonic Fingerprint Scanner


Optical fingerprint scanner:


Fiber Optic Plate


This technique is a new fingerprint scanner. In this technique, Fiber Optic Plate (FOP) can transmit the fingerprint signal from the top surface to the other surface that coupled with sensor.


In the same way, Optical Micro-Channel Array Plate can be applied to fingerprint identification technology under the screen of mobile phone as an optical imaging element. 

This is quite advanced technology. In a very small thickness (0.10~0.25mm), Optical Micro-Channel Array Plate can realize collimation of incident light, and combines with image sensor to realize fingerprint imaging under the screen.

Micro-Channel Array Plate


Capacitive Fingerprint Scanner

Optical Fingerprint Scanner

This type of touch sensor is used in phones nowadays. In this fingerprint scanning technology, there are capacitors installed on the scanner. When you place your finger on the sensor capacitors of the part of the finger that touches the sensor is activated. And this way it creates a map of the finger from different angles. 


Ultrasonic Fingerprint Scanner:

Fiber Optic Plate

This is a new technology in the fingerprint scanning technology and is used in very few flagship smartphones.

In this technology, the hardware consists of an ultrasonic transmitter and receiver. The Ultrasonic transmitter sends some signal when you place your finger on the scanner. Which touches your finger, some of which is left on the finger and the remaining Signal is returned and the receiver receives the returned signal and creates a 3D image from it. But it consumes a lot of power.



Conclusion:


In Smartphones, capacitive fingerprint sensors are the most popular. Optical fingerprint sensors and Ultrasonic sensors for on-screen fingerprint lock system are still in the development period.


Optical fingerprint sensors with FOP or Micro-Channel Array Plate is more likely to achieve full screen fingerprint identification. This makes it possible to unlock the phone with more features and applications. 


In optical fiber industry, Guangzhou HONSUN Opto-Electronic Co., Ltd has rich experience and leading technology. Micro-Channel Array Plate is a new product independently developed by HONSUN, which is very competitive in fingerprint identification technology under the screen.




Please feel free to give your inquiry in the form below. We will reply you in 24 hours.
Message