In this article we will talk about fingerprint readers. This is a completely new way of protection, which is used relatively recently. True, for the first time this type of protection began to be used on laptops and PCs, then it smoothly switched to phones. And today you can find many models of smartphones that have fingerprint locks.
What is a fingerprint scanner
This is a type of security technology based on biometric data. It allows you to use a combination of software and hardware methods in order to recognize the fingerprints of a particular user. Using this method, it is possible to identify and verify the authenticity of a person’s fingerprint in order to deny or allow access to a specific application, smartphone, laptop, as well as other places that need protection from interference.
It is worth noting that there are many other options for protecting information, for example:
- scan of the iris;
- biometrics;
- retinal scan;
- scanning facial features;
- even a special analysis of gait or blood.
But today it is not used in household appliances. True, there are smartphones that scan the iris of the eye. But the implementation of such protection is complicated, so the functioning of the system is far from ideal.
Why prints?
One wonders why fingerprints are used. But everything rests on the cost and ease of manufacture. Firstly, scanner boards are very cheap. Secondly, they are very simple to make. And most importantly - it is very easy to work with them when operating the end equipment. Just touch the scanner of your phone or laptop, as it will be immediately unlocked. There are three types of sensors that allow you to analyze fingerprints:
- Ultrasonic
- Optical
- Capacitive.
Positive aspects of using scanners
There are several advantages that can be distinguished when using such devices in phones and other equipment:
- You can lock and unlock the gadget with just one finger.
- This is a good way to identify people.
- Duplicating or faking this technique is very difficult.
- If you can pick up a PIN or password, then it’s almost impossible to crack or guess the fingerprint.
- You can forget the password, but the fingerprint will always remain with you (if it is not cut off, of course).
Disadvantages of using scanners
But you can identify the cons that are still present in such sensors:
- The work is not reliable, if you really want to, you can fool the scanner using fakes or prints taken from any surface.
- There is no way to get new fingerprint samples. If you use passwords, codes, cards, then they can be replaced if necessary. But if your fingerprint becomes available to someone, you won’t be able to make a new one.
- The degree of encryption may also be in doubt. The security of all the data stored on your computer depends entirely on who produces the software or hardware.
- The presence of even a small defect on the skin of a finger can cause difficulties during scanning, as a result of which access to resources will be denied.
Therefore, this technology is used exclusively in simple electronics. It is new, so it does not work perfectly.
Read Issues
There are several reasons why user authorization may not occur. In the event that the sensor stops working, you need to look for a problem. And it can be covered in the following moments:
- The user's hands are greasy or wet.
- There was a failure in the electronics, for this you need to turn off and then turn on the device again.
- There is a defect on the finger. A small scratch is enough for the biometric fingerprint reader to stop working.
As a rule, manufacturers of telephones and other equipment have provided such moments, so for the most part you can unlock the device by entering a PIN code or password.
Optical scanners
Optical are the oldest, such a technique for capturing and comparing prints has been used for a long time. This method is based on the fact that the capture of the image of the fingerprint occurs. This is a photograph of a fingerprint, which, after capture, is processed using special algorithms that allow you to detect unique patterns on the surface (ridges, unique curls). In this case, the analysis of the lightest and darkest areas of the image.
The sensors have a final resolution, the higher it is, the smaller elements of the pattern it can distinguish on a finger, the higher the degree of security. The sensors of these sensors have greater contrast than a simple camera. They have more diodes per inch. This is necessary in order to capture images at very close range.
Optical scanners also have arrays of LEDs that work as a flash. They illuminate the scan area. The design is very bulky for phones, as the thickness of the case is of great importance. But even a fingerprint reader for access control systems using such a technology cannot be built - the degree of information protection in this case is extremely low. You can fake a print in various ways.
The main disadvantage of this type of scanner is that it is very easy to trick them. Scanners only capture a 2D image. You have probably seen how, with the help of simple manipulations with PVA glue or even with a high-quality finger photograph, a scanner is hacked, an attacker appears to have access to all important documents. Therefore, this type of security is not suitable for modern smartphones.
Capacitive Scanners
This is a common type of fingerprint scanner. As the name implies, a capacitor is used as the main module. Capacitive scanners use arrays of small capacitor circuits to collect fingerprint data. An electric charge is stored in the capacitors, and when you put your finger on the scanner, the charge accumulated in the capacitor will be changed in places where the crest of the pattern touches the plate. And the charge remains relatively unchanged in places where the depressions are on the pattern. Such a fingerprint reader for a computer can be effectively used to protect information, but it still will not be ideal.
After capturing the fingerprint, the data is converted to digital form and already in this array the search for distinctive and unique features of the fingerprint begins. They can be saved in order to make comparisons at later stages. The main advantage of this technology is that it is significantly better than optical scanners.
Ultrasound scanners
Ultrasonic fingerprint scanners are currently the latest fingerprint recognition technology. The ultrasound scanner uses a transmitter and a receiver to recognize the fingerprint. The pulse is transmitted directly to the finger, which is placed in front of the scanner. There are HP fingerprint reader models that connect to your computer. And when installing the appropriate software, you can restrict access to certain folders on the device.
Part of this pulse is absorbed, part returns back to the receiver and is recognized. Depending on the depressions, ridges and other details of the fingerprint, which are unique to each finger, a "drawing" of the fingerprint of the owner is made. In ultrasound scanners, a sensor that detects mechanical stress is used to calculate the intensity of the ultrasonic pulse at various points on the scanner.