3 Different Types of Biometric Scanners

Biometric scanners have revolutionized the way we authenticate and secure our information. With advancements in technology, different types of biometric scanners have emerged, each with unique features and capabilities. Optical, ultrasonic, and capacitive scanners are among the most popular. In this article, we will delve into the working mechanisms and unique features of these three types of biometric scanners.

Optical Scanners

Optical fingerprint scanners are the most commonly used biometric authentication devices. You frequently encounter these scanners in various settings, such as banks, immigration offices, and point-of-sale systems.

As the name suggests, optical fingerprint scanners function by capturing a detailed 2D image of fingerprints. Their advanced technology enables them to detect and analyze the unique patterns formed by the ridges and valleys of the fingerprint based on variations in light reflection.

The scanner converts these variations in light intensity into a digital image, creating a detailed representation of the fingerprint’s ridges and valleys. Once the digital image is obtained, it is swiftly cross-referenced with an existing database to determine whether a match exists for the fingerprint.

Ultrasonic Scanners

Ultrasonic biometric scanners are the talk of the town in the field of biometric identification. Instead of relying solely on optical properties, ultrasonic scanners emit ultrasonic waves to provide a detailed 3D rendering of your fingerprint.

When a finger is placed over the scanner, an ultrasonic pulse is emitted. The sensor detects the variation in pressure caused by the ridges and valleys of the fingerprint. Some of the pulse’s pressure is absorbed, while the rest is bounced back to the sensor, allowing for an accurate capture of the fingerprint’s distinct features.

One of the most significant advantages of ultrasonic fingerprint scanners is their remarkable speed. Because they do not rely on light to capture fingerprint data, the scanning process is considerably faster than that of optical sensors. If you are considering biometric scanners, here are examples of 10 fingerprint scanners to buy.

Capacitive Scanners

Capacitive fingerprint scanners use an array of tiny electrodes to measure the electrical capacitance between the electrodes and the fingerprint. When a finger is placed on the electrodes, each capacitor can measure the capacitance of the part of the fingerprint with which it is aligned.

As the ridges come into contact with the tiny capacitors, the capacitance changes because of the conductive skin. Conversely, the valleys on the fingerprint do not come into contact with the electrodes, resulting in different capacitance values. This variation in conductivity changes the electrical capacitance between the electrodes, ultimately enabling the creation of a digital fingerprint representation. Algorithms analyze the generated data to generate a digital rendering of the fingerprint. The image runs through an already stored database to verify the identity of the user.


As the adoption of biometric authentication continues to grow, it is an efficient way to secure access without relying on vulnerable traditional methods such as passwords. Optical scanners are widely available, whereas ultrasonic scanners impress with their speed. Capacitive scanners offer a balance between these two approaches, providing a reliable and affordable solution applicable to different industries. Visit the Biometric Supply online store to find the ideal biometric scanner for your security needs.