Optical Fingerprint Scanner vs Ultrasonic Fingerprint Scanner

Optical fingerprint scanners and ultrasonic fingerprint scanners are both a way to verify identity. This chapter will introduce you from different angles, such as principles, working methods, performance comparison, etc.

What are they？

Optical fingerprint scanner

The technology of optical fingerprint scanner is to obtain fingerprint image through optical sensor, which is equivalent to taking a picture of fingerprint. The sensor will emit light to the fingerprint, and capture the fingerprint image by reflecting the light and measuring the surface.

Ultrasonic fingerprint scanner

Ultrasonic fingerprint scanners use ultrasonic technology. The sensor emits ultrasonic pulses. When the ultrasonic waves encounter the lines on the fingertips, they are scattered and refracted. The sensor receives the reflected ultrasonic information and extracts fingerprint features by analyzing the changes in the ultrasonic signal.

check here for types of fingerprint scanner

How do they work

The working principle of optical fingerprint scanner and ultrasonic capacitive fingerprint scanner is the same. They obtain fingerprint images, process the images, and form image feature templates for comparison or recognition. However, the principles are different.

• Acquisition
• Image analysis
• Image feature template
• Comparison

Performance Comparison

Speed of Scanning：

Scanning speed:

The scanning speed of an optical fingerprint scanner can be completed in 1 second, because the scanner starts to capture the fingerprint image when it contacts the sensor;

Ultrasonic fingerprint scanner takes a little time to capture the fingerprint, which requires it to create a detailed 3D image for you, but the time is basically completed within 1 second;

Data processing speed:

When the optical fingerprint scanner uses a better algorithm, the fingerprint analysis, extraction and comparison are usually completed within 1~2 seconds

Ultrasonic fingerprint scanner needs to process 2D and 3D data, which takes a certain amount of time to complete. With the continuous optimization of fingerprint algorithms, the processing speed of ultrasonic fingerprint scanners can also be completed in 1~2 seconds

Accuracy and Reliability

Accuracy:

The accuracy of optical fingerprint scanners depends largely on the quality of the image, lighting conditions, and the resolution of the sensor. External factors, if the finger is in bad condition and is greasy, water-stained, or dirty, will affect the accuracy of the fingerprint;

Ultrasonics uses ultrasonic technology to capture a more complete 3D image and can even capture fingerprints through certain materials. Therefore, it is not affected by external factors and has higher accuracy than optical fingerprint scanners;

Reliability:

Optical fingerprint scanners are usually reliable when all environments are just right; ultrasonic fingerprint scanners are reliable in any case and are not affected by any environment

Accuracy and reliability comparison summary

Security Features

You have different choices for different conditions and different needs.

Security Features

Image capture:

The fingerprints collected by optical scanners are 2D images, so they are easily deceived by high-resolution fingerprint images or printed images;

Ultrasonic fingerprint scanners capture 3D images, which have more feature points and more detailed information, making them difficult to copy or steal

Live detection:

Not all optical fingerprint scanners have live detection function.

Ultrasonic fingerprint scanners are now widely used for live detection, which can effectively detect fraudulent fingers

Advantages and disadvantages comparison

Advantages:

Optical scanner:

Low cost:

The composition and hardware of optical fingerprint scanners are relatively mature and complete, and the overall cost is lower than that of ultrasonic fingerprint scanners.

Widely used:

For common attendance and identity recognition, optical fingerprint scanners are more widely used than ultrasonic fingerprint scanners.

Ultrasonic fingerprint scanner

Anti-dirt and scratch:

Ultrasonic fingerprint scanner uses ultrasonic technology and is not affected by environmental dirt.

Adaptability:

No need to completely lift the sensor, high contact sensitivity

Disadvantages

Optical Fingerprint Scanner:

Contact:

High contact sensitivity, finger needs to completely touch the sensor to obtain fingerprint

Environment:

Easily affected by the environment and fingerprint status

Forgery:

Low liveness detection, easy to be forged and deceived

Ultrasonic fingerprint scanner

High equipment cost:

The hardware level and software algorithm are relatively expensive;

Fingerprint Scanner Standards

Whether it is an ultrasonic fingerprint scanner or an optical fingerprint scanner, it must comply with the fingerprint standard protocol

1. ISO/IEC 19794-2:
   Data exchange format for fingerprint images and templates;
2. ISO/IEC 30107-1
   Provides an evaluation framework for biometric systems to resist fraud
3. FIDO Alliance Standards
   Developed by the FIDO Alliance, it provides open standards for online identity verification
4. Biometric Performance Testing Standards (NIST and ISO)
   Provides standard requirements for various performances of fingerprint scanner devices

Application

Currently, the use environment of ultrasonic fingerprint scanners is relatively small, suitable for smartphones; the use of optical fingerprint scanners is more advertising

• Access Control:
• Identify Recognition
• Smartphone

Future

The technical barriers will eventually be broken due to the improvement of technology. The choice of optical fingerprint scanner or ultrasonic fingerprint scanner depends on your application.

HFSECURIT is a Biometric identify solution provider with 19 years of experience, escorting your identity identification