Thanks to its intelligent and accurate recognition capabilities, optical fingerprint sensors have become the top choice in many security solutions. Let's find out what an optical fingerprint sensor is with Intech Group in the article below.

What is an optical fingerprint sensor?

Optical fingerprint sensors are biometric recognition technology that works based on the principle of light reflection. When the user places their finger on the sensor area, the system will illuminate the fingerprint surface and record the reflected image using a high-sensitivity optical sensor.

Optical fingerprint sensors are often integrated in devices using OLED or AMOLED screens, because each pixel on these types of screens has the ability to emit light independently. This allows optical sensors to record fingerprint structure details clearly and accurately. In contrast, LCD screens do not support optical fingerprint sensors because they do not meet the requirements for independent illumination and reflection of each pixel.

After recording the fingerprint image, the internal microprocessor will analyze the characteristic concave and convex features to compare with the stored data. If it matches, the device will be unlocked. It is the use of advanced technology that the error rate of the optical fingerprint sensor can be less than 10%, providing high security and fast unlocking speed.

What is a semiconductor fingerprint sensor?

Semiconductor fingerprint sensor is an advanced biometric technology, capable of accurately recognizing real fingerprints and effectively preventing counterfeiting behaviors, often used in high-end security systems thanks to its outstanding recognition features and almost absolute safety.

The operation of the semiconductor fingerprint sensor is based on two main mechanisms:

• Live (Biological scanning): Use infrared rays to recognize fingerprints on the surface of real skin, while removing dead cells. This mechanism helps distinguish between real fingers and fake samples such as silicon, rubber or fingerprint images, achieving nearly 100% anti-counterfeiting ability.
• Scan (Record fingerprint details): Record the microstructure of each fingerprint layer, then encode and process the information with intelligent algorithms to ensure maximum accuracy in user authentication.

In addition, the semiconductor fingerprint sensor also integrates temperature measurement technology and analyzes the contact area of ​​the fingertip, contributing to increasing efficiency in the identification process.

Advantages and disadvantages of optical fingerprint sensors

Advantages of optical fingerprint sensors

Optical fingerprint sensors are widely used in many electronic devices and security control systems such as smartphones, smart door locks, timekeeping machines, etc. Thanks to the technology of scanning fingerprint images with light, this technology brings many outstanding benefits:

Fast recognition speed: Users can unlock with just one touch. The fingerprint image processing system and fast information authentication bring a superior experience.

Good security: Only when the fingerprint is accurate can the device be unlocked. This helps prevent unauthorized access and increase the level of safety for users.

Easy to use: The fingerprint registration and use process is simple, suitable for both adults and children without complicated operations.

Storing multiple fingerprints: This technology allows storing many different fingerprint templates, convenient for families or organizations with many people sharing the device.

Disadvantages of optical fingerprint sensors

Poor performance when hands are wet or dirty: Optical sensors require a dry and clean skin surface for accurate recognition. When hands are wet, sweaty or dirty, the recognition ability will be reduced.

Easily fooled by fake images: Despite its relatively high security, optical fingerprint sensors are still at risk of being fooled by images or fingerprint copies if there is no live detection technology.

Optical fingerprint sensor operating principle

Optical fingerprint sensors operate based on the principle of recording fingerprint images through reflected light. Specifically, this technology uses an OLED screen with the ability for each pixel to independently light up. When the user touches the finger on the sensor area, the pixels will light up the skin surface to clearly display the fingerprint lines.

The light reflected from the fingerprint will be recorded by the lens and transmitted to the ultra-sensitive optical sensor, where the image is processed. An integrated microprocessor will then use an algorithm to analyze and encode the fingerprint image into user identification data.

Due to the requirement of independent light emission, optical sensors are only compatible with OLED screens and do not work on LCD screens. This explains why this technology mainly appears on high-end phones or devices.

Although providing fast and convenient recognition, optical sensors still have some limitations in terms of security. The recorded fingerprint image is only in 2D form, which can be easily fooled by copies or fingerprint photos without advanced biometric verification measures such as “live detection” technology.

During the unlocking process, the system will compare the new fingerprint image with previously registered data, based on geometric features such as ridges, slots, concavities, etc. The recognition error is usually less than 10%, ensuring sufficient speed and accuracy in normal situations.

Applications of optical fingerprint sensors

Optical fingerprint sensors are now widely used in many fields thanks to their ability to recognize quickly, accurately, and easily integrate into technology devices. Here are some typical applications:

1. In the consumer electronics industry

Optical fingerprint sensors are commonly used in smartphones, tablets, and laptops, especially devices using OLED screens that allow the sensor to be integrated right under the screen, providing a fast, convenient, and space-optimized unlocking experience.

2. In the field of engineering and automation

In automatic control systems and industrial electronic equipment, optical fingerprint sensors play a role in access control, user authentication and support the operation of internal security systems.

3. In businesses and offices

Optical fingerprint sensor technology is integrated in timekeeping machines, smart door locks, access control systems, helping to effectively manage human resources. Thanks to the ability to quickly recognize and store multiple fingerprint templates, this technology helps reduce authentication time and enhance security in the working environment.

4. In biometric identification

Optical fingerprint sensors are one of the popular biometric authentication technologies, used in identity recognition systems, personal security devices and medical applications. The ability to recognize through reflected images helps to identify individuals easily and quickly.

Optical fingerprint sensors are increasingly asserting their important role in modern electronic devices and smart security systems. Hopefully, through this article, you have clearly understood what an optical fingerprint sensor is, how it works and its practical applications. If you are looking for a convenient and modern security solution, an optical fingerprint sensor is definitely a choice worth considering.

• AGV self-driving vehicle sensor technology

• AGV Robot line using sensors