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What is a Fingerprint Sensor?
People tend to lean towards biometrics when there’s a high demand for security. Plus, when paired with other forms of protection, like passwords, it provides advanced security levels.
The finger sensor is a biometric system that can capture and recognize a human fingerprint. As we mentioned earlier, each person has a unique fingerprint that helps with identification. Fingers have ridges that create up to five types of prints, including whorl, left loop, right loop, arch, and tented.
Fingerprint
Fingerprint sensors primarily work for devices that require better performance and accuracy than regular passwords.
Hence, you don’t have to worry about problems with similar fingerprints. Fingerprint sensors come with built-in fingerprint detection modules that distinguish fingerprints. And it achieves it by discovering the ends of a finger’s ridge.
In addition, fingerprint sensors offer a more accessible and safer way to lock and unlock devices. Also, fingerprints can serve as digital passwords that you can’t forget.
Device Safety
How Does a Fingerprint Sensor Work?
Enrollment and matching are the main factors forming a fingerprint sensor’s working principle. Before using any fingerprint sensor, you must enroll your print into the device’s database.
You bought a new mobile phone with a fingerprint sensor and want to activate your biometrics security. Now, the device will ask you to place your finger on the sensor multiple times to successfully enroll your fingerprint.
But that’s what happens on the surface. While enrolling, the sensor generates a fingerprint pattern based on your finger and stores it in code form for matching.
Once you’ve successfully enrolled, the sensor will scan and turn your scanned fingerprint into a code. Then, it matches the code to the one stored in its database. Afterward, it automatically unlocks the device or system. If it doesn’t fit, it will deny access.
Three Scanning Methods of a Fingerprint Sensor
Additionally, a fingerprint sensor can use three scanning methods to enroll and match fingerprints: optical, capacitive, and ultrasonic scanning.
Optical Scanners
Optical scanners shine a bright light over your finger to take high-resolution digital fingerprint photos. Plus, it’s similar to placing your hand on a photocopy machine.
But, instead of capturing a dark photocopy, it sends your captured print to a device for storage.
Optical scanners
Also, optical scanners use light-sensitive microchips to create visual images. These light-sensitive microchips can be either CCD or CMOS sensors.
Afterward, the device connected to the optical sensor does three things:
- Analyzes the image
- Selects only the fingerprint
- Turns the fingerprint into a code with advanced pattern-matching software
Capacitive Sensors
Once you place your finger on any surface, your fingerprint ridges contact the surface, while the hollows between the banks don’t precisely touch the surface. In contrast, capacitive sensors use an electrical current to measure your finger.
Hence, there are different distances between the parts of your finger and the surface you’re touching. Again, this distance is what a capacitive sensor measures to generate an image of your fingerprint. Also, capacitive scanners are similar to phone touchscreens and don’t work well with moist fingers.
Though capacitive sensors are more secure and faster than optical sensors, you can damage them with static electricity. And that’s if you use them continuously with wet fingers.
Ultrasonic Fingerprint Scanners
Alternatively, the ultrasonic fingerprint sensor uses ultrasound instead of electricity or light to analyze your fingerprints. Hence, you can find ultrasonic scanners on new-model smartphones. Plus, ultrasound sensors scan fingerprints in 3D–making them more secure than optical scanners. However, ultrasonic scanners are usually slower than capacitive sensors.
How Do You Install a Fingerprint Sensor?
You can either install a USB-powered fingerprint sensor on your device or install it with an Arduino. Let’s take a closer look at both.
USB Fingerprint Sensor
First, connect your fingerprint scanner to your device via a USB port. If it works, your computer will recognize the device. Next, install the software for your reader. You can use the installation disk with the reader or download the matching software online.
After installing the software, you can use your fingerprint sensors. Then, try pressing your finger on the sensor and registering your fingerprint. If it works, then your connection is successful. However, some models may require you to configure additional settings.
Afterward, you can start using your fingerprint to unlock your device.
Fingerprint Sensor with Arduino
You only need a few components for connecting the fingerprint sensors to Arduino. These components include:
- A fingerprint sensor module
- Breadboard
- Power bank
- Connecting wires
- TFT display
- Arduino board
Step 1: The pins of the fingerprint sensors include a DNC, VCC, TX, RX, and GND pin. Hence, use a white wire to connect the DNC pin, red for VCC, blue for TX, green for RX, and black for GND.
Step 2: To connect the fingerprint sensors to the Arduino, join the black wire to the GND pin, red to the 5V pin, green to pin 2, and white to pin 3.
Step 3: You can also connect the display to the Arduino by clicking the following order:
- Link the VCC of the TFT display to the 5v pin of the Arduino
- GND to GND
- CS pin to digital pin 10
- RST pin to digital pin 9
- A0 pin to digital pin 8
- SDA pin to digital pin 11
- SCK pin to digital pin 13
- The LED pin to the 3.3v pin
After the following connections, upload the code below using the Adafruit fingerprint library for the sensor. And the Adafruit GFX and Sumotoy libraries for the display.
Arduino Code
Arduino Code
Not Working
If your fingerprint sensor does not work after a successful connection, you can either troubleshoot the problem or replace it. You can also check the manual for troubleshooting options.
If using an Arduino connection, connect all pins properly or check if you have faulty equipment.
Applications
Fingerprint sensors primarily work for security applications. Hence, you can use them to secure your phone’s computers, access buildings, and even capture data.
Fingerprint Access
Source: Pixabay
Closing Words
Fingerprint Scanning
Fingerprint sensor scanning is more popular than any other form of biometric security. One advantage of fingerprint scanning is that it protects your device, information, or property from criminals or intruders. Plus, it’s easy to use and stores data securely.
Hence, if you need a better way to secure your private information and use a fingerprint sensor, you won’t have problems like forgetting your password or keys again.
If you have any more questions about fingerprint sensors not covered here, don’t he’s it ate to reach us.
