It is quite difficult to recall a world without fingerprint scanners and other biometric authentication means in smartphones. Before their mass distribution, most of us simply did not use protection to unlock our gadgets, and everyone else really mocked ourselves by regularly entering passwords or drawing graphic keys. Moreover, this was repeated during the use of banking and other applications, the confidentiality of data inside which was always in the first place. When you think about all this, the mood begins to spoil and the left or right eye twitch (optional).
It is precisely fingerprint scanners that remain the most popular means of biometric authentication today, and it was Apple that brought the normal options into the world of modern user electronics. Many are sure that so far she has already managed to abandon such sensors, but this is not so. The company still uses them on the iPad without the Pro prefix, and even, according to rumors, wants to release a brand new iPhone 9 just with a limb reader. Actually, this is an occasion to recall the past of fingerprint scanners, look at their present and look into the future.
A short history of fingerprint scanners in our gadgetsThe main impetus for fingerprint scanners in smartphones was the release of the iPhone 5s, which was introduced in September 2013 - almost seven years ago. Prior to this, this method of biometric authentication in gadgets was practically not used. However, many were waiting for it in Apple smartphones much earlier. The company secured the appropriate sensor with a patent back in 2008, but spent the entire five years to bring the technology to mind. As a result, the fingerprint scanner was called quite simply - Touch ID. The word “just” is very appropriate here, because before that it was all too complicated.
In general, fingerprint scanners initially began to appear by no means in smartphones. One of the first devices with this authentication method was the Acer TravelMate 739TLV laptop. Just imagine, in order to recognize a finger, it took him more than ten seconds. Of course, during this time a more or less experienced user could enter the password from the computer several times, even with his eyes closed. In 2002, Hewlett Packard launched the HP iPAQ H5400 handheld computer with a similar clumsy sensor, which also did not cause a storm of rave reviews. Long, expensive - there were enough claims.
Motorola Atrix 4G (Source: 24Gadget)
In more or less modern smartphones, the fingerprint scanner was one of the first to appear in the Motorola Atrix 4G. The sensor was combined with the power button and was located on the upper edge of the device. It could be customized for the index finger of the right or left hand - yes, then the gadgets were small enough to reach such a control in this way. For the scanner to recognize the finger, it was not enough just to attach it to it. After touching the site, the screen lights up, and after that it was also necessary to draw a pad over it. After that, the gadget needed another half a second to read and analyze.
Such an implementation cannot be called convenient even with a big stretch - too slowly. It was much faster just to press the power button, and then enter the four-digit password. Moreover, such a scanner might not work at the “wrong” speed of driving on it with a finger. And the location was not the most successful - it was possible to try it only with the standard grip of the gadget, which, as practice shows, is not always possible. In general, before the iPhone 5s with its fast and accurate Touch ID, there was nothing sensible in the Home button. It became a small revolution precisely because of speed and convenience.
iPhone 5s (Source: Kanobu)
After the iPhone 5s, Apple updated the Touch ID, making it even faster - its scanner was considered the reference, even when competitors filled the market with similar solutions. But with the release of the iPhone X in 2017, the company made it clear that it was halting its development. The main feature of this device was Face ID - a face scanner, which is located in the neckline of the screen. Until now, it remains one of the most reliable, accurate and convenient solutions for biometric authentication. However, other manufacturers did not abandon the fingerprint scanner after Apple and continued its active development.
Where can fingerprint scanners be located in smartphones?Initially, following the notorious iPhone 5s, fingerprint scanners were located on the front panel. This is not surprising, because at that time the struggle for the maximum screen area had not yet been waged, and there was enough space with our head. However, then Google decided to abandon the physical buttons under the display and added the ability to use virtual analogs to Android - technology pulled itself up. As a result, screens replaced any additional elements from the front panels of smartphones - many companies even had to remove their logos, to say nothing of scanners. They were moved.
iPhone 8 and iPhone 8 Plus (Source: Pinterest)
On the front panel. Oddly enough, the fingerprint scanners on the front panel can still be considered relevant. Most companies have found another place for them, but many remain true to their traditions. A vivid example is Apple. To begin with, she still releases the iPhone 8 and iPhone 8 Plus with Touch ID in the Home button below the screen. And you can end up with the fact that the company is likely to retain the same location for the sensor in iPhone 9. This is a notorious sequel for iPhone SE, which will become an inexpensive ideological successor to the G8.
HONOR 10i (Source: MobRev)
On the back. Where to transfer the fingerprint scanner if the entire (well, almost) front panel is already occupied by the screen? The obvious solution was to use the back, on which, in addition to a set of cameras, additional space is not needed for anything. Today, the scanner on the back is the lot of low-cost smartphones like the HONOR 10i and the like. This approach has one main drawback - such a sensor becomes useless if the gadget is on the table or on a holder in the car. Actually, that is why in the more expensive segment a fingerprint scanner is not placed on the rear panel.
HONOR 20 (Source: SuperPlanshet)
On the side faces. The trade-off between the inconvenient rear and full-time front panels for many manufacturers was the side faces. This decision did not become widespread, but some companies began to integrate fingerprint scanners into power buttons. The role of the example will again be performed by the brainchild of the Huawei sub-brand - the HONOR 20 smartphone. The sensor, which can recognize the pattern on the skin, is located in the power button in it. It turned out to be a little more convenient than the back, but the whole bunch of questions on usability did not close. The front panel would be much more convenient, but there is no place.
Right on the screen. One of the first smartphones with a fingerprint sensor, which was managed to be hidden right on the screen (in fact, it is under the matrix), was the Vivo NEX. This prototype gadget came out in the summer of 2018 and surprised. Nevertheless, then it quickly became clear that the technology was new, not fully tested and needed to be improved. The response speed of such sensors has already reached a comfortable level, but there are still questions about their safety. The network is constantly breaking news about breaking such solutions with the help of three-dimensional copies of fingers and even a protective film (hi, Samsung Galaxy S10).
What is the difference between capacitive, optical and ultrasound scannersOptical, capacitive, thermal, ultrasonic, radio frequency and so on - there are more than enough fingerprint scanner technologies on the market. To a greater extent, it is precisely their choice that determines the accuracy of the sensor and finger recognition. However, you should not lose sight of the performance of the gadget, which also plays an important role. The processor, not least depends on how quickly the device recognizes its owner by finger. But the three of the main fingerprint technologies - it is impossible to say unequivocally which fingerprint scanner is better.
iPhone 6s (Source: Business Insider)
Capacitive. Such fingerprint scanners work on the basis of capacitor arrays that store an electric charge. When a finger touches the sensor, the charge of each specific capacitor changes, and after analyzing their entire network, it becomes possible to create a print pattern. Convex spots on the skin clearly change the state of charge, and the hollows leave it virtually unchanged - that’s all “math”. It is this technology that Apple uses in its smartphones that are equipped with Touch ID. It is still considered the most common.
How a capacitive scanner works (Source: Android Authority)
Among the obvious advantages of this technology is its high accuracy, which other solutions hardly reach. But she also has disadvantages. The main thing is that today it cannot be built into the screen, and this makes it irrelevant for most modern gadgets.
Xiaomi Mi 9 (Source: Mobiltelefon)
Optical Judging by the name, it is not so difficult to guess that this method of biometric authentication is based on the capture of an optical image of a fingerprint. If you exaggerate, the sensor using this technology takes a picture of the skin on the skin at the time of touch and compares it with the one that was saved during setup. For such a scanner to work, backlighting is necessary - that is why during its use the screen lights up in a bright (usually green) color. A clear example of a smartphone that uses this technology is Xiaomi Mi 9 with a fingerprint scanner on the screen.
How an optical scanner works (Source: Vishnumaiea)
Among the advantages of this technology is its low cost, which is why it is used in relatively inexpensive smartphones. Among the shortcomings there was a place for not the highest security. Since the technology works with a 2D image, it’s easier to trick it than competitors.
Samsung Galaxy Note10 (Source: PHP)
Ultrasonic This relatively new fingerprint reader technology is just starting to gain popularity. To determine the pattern on the skin of the fingers during touch, she sends ultrasound in their directions and reads the signals that have returned back. With long-term scanning using this method, you can generally create an accurate three-dimensional model of the finger. However, fast is enough for secure authentication. A striking representative of the "genre" is the Samsung Galaxy Note10, which is also distinguished by other top technologies.
The principle of operation of an ultrasound scanner (Source: SlidePlayer)
Among the advantages of this solution is high accuracy. But the drawbacks of the pair: the technology is quite new, so it’s sometimes “not happy” with the most stable operation, and it’s still very expensive, therefore it is used only in top solutions of companies from the secret group AAA.
What algorithms do fingerprint scanners use in smartphones?With fingerprint scanning alone, technology does not end there. After the sensor has created an image of the skin on the fingers, it still needs to be compared with the reference. There are two nuances that are used by almost all smartphone manufacturers.
Fingerprint Scanner Operation Algorithm (Source: ubergizmo)
Firstly , usually the fingerprint confirmation algorithm does not take into account its entirety. Often it is enough for him to find a small unique detail that does not repeat itself. It is her, following the example of the standard, that he seeks in all folds of the skin that appears on the sensor. This saves both time and energy.
Secondly , to store the reference image, you need a special place in the smartphone’s memory, which applications and ill-wishers will not have access to. Apple has Secure Enclave and Qualcomm has Secure MCM. These are separate parts of the head chip with all such data.
Why manufacturers do not move away from fingerprint scannersAs mentioned above, not so long ago, Apple partially abandoned fingerprint sensors in favor of face scanners. The question is why competitors are in no hurry to follow her example. The case at Google, which was in no hurry to add a face definition to trusted authentication methods.
Xiaomi Mi 8 (Source: ePHOTOzine)
A vivid example is Xiaomi Mi 8, in which an advanced Face ID level scanner from iPhone X appeared. However, apart from unlocking the device, nothing interesting could be done with it. Therefore, already in Xiaomi Mi 9, the company switched to more primitive facial recognition methods.
Now using Face ID you can not only unlock your iPhone, but also go to any banking and other secure applications. Until recently, Google allowed to do all this with a fingerprint. Only in Pixel 4 with its advanced face scanner did you unlock access to everything and everything with it. It is likely that in the future there will be smartphones on Android, which will also use this chip. That's just, it’s now obvious that finger sensors are in the first place among manufacturers today - they seem to be made as opposed to the main competitor.
Summing up: the prospects for the development of all authentication methodsToday, there are no at least some significant rumors about the emergence of new methods of biometric authentication. That is why, most likely, manufacturers will focus on two relevant ones: face and fingers. Samsung still had findings in scanning the retina, but so far it is working too slowly and not always confidently. Chances are that
Sub-screen version of Touch ID will be adopted by Apple. Nevertheless, in the near future the company is unlikely to completely abandon Face ID in favor of it - it will probably use two systems at once, as competitors.