Is it true that the larger the area of the fingerprint head of the smart lock, the more accurate the recognition? If you want to have a good user experience, correct installation is the key!
In recent years, the sales of face locks and video locks have grown very well, but judging from the data released by authoritative organizations, we can still see that fingerprint recognition modules are still standard biometrics in terms of market stock and new products launched by brands.
As the most widely used biometric method on smart locks, careful friends may have discovered that some tuya smart door lock have larger fingerprint recognition heads, and some are relatively smaller.
Compared with modules with a smaller area, the large-area fingerprint module has a larger skin coverage. So, is it better in terms of recognition accuracy and security?
At present, most of the fingerprint heads of smart locks are capacitive sensors. This sensor consists of a capacitor array, which contains about 10,000 miniaturized capacitors. When the user places a finger on the front, the skin forms a plate of the capacitor array, and the back of the capacitor array is an insulating plate. Since the distance between the ridges and valleys of fingerprints in different areas is not equal, the capacitance of each unit changes accordingly, and thus the fingerprint image can be obtained.
The specifications of fingerprint recognition sensors in the industry are generally 160*160, 112*88, 80*64 and other specifications, and 160*160 and 112*88 are the most commonly used specifications. Among them, a fingerprint with a larger AA area (operable area) can obtain more fingerprint images at one time, which is of great help to FRR (rejection rate) and FAR (false recognition rate) of fingerprint identification. For a fingerprint identification module with a larger area, if the AA area is small, it is more likely to miss the target.
However, the area of the fingerprint sensor we usually see is not exactly equal to the area of the AA area. In other words, a large-area fingerprint sensor only determines the upper limit of fingerprint recognition performance, not the lower limit.
Therefore, the larger the area of the fingerprint module, it cannot 100% mean that the recognition performance is better. It is reported that the larger the area of the fingerprint module, but if the AA area of the internal chip remains unchanged, the miss rate of finger pressing will also increase.
From the perspective of technology, the current capacitive fingerprint module generally has two kinds of technology, Coating and glass cover, which are mainly reflected in the difference in surface treatment: 1. Coating is to directly spray ink on the surface of the fingerprint chip, usually three coatings, respectively Primer, mid coat, top coat. 2. The glass cover solution needs glue or glue on the surface of the fingerprint chip, and degassing after the glass cover is bonded.
In terms of small-area fingerprint modules, in recent years, with the continuous improvement and maturity of capacitive fingerprint technology, and the serious involution of the industry, the AA area of fingerprint recognition modules will become smaller and smaller in the future due to the impact of cost control. The performance of the MCU will be higher.
Based on the above, it can be seen that:
❶ What affects the recognition performance of the fingerprint module is not the area of the appearance, but the area of the AA area (the area of the working area). The larger the AA area, the more fingerprint images can be obtained at one time, and its impact on FRR (rejection rate) and FAR (false recognition rate) is also more obvious.
❷ Don't blindly pursue a large-area fingerprint module. If the AA area is small, the recognition performance will be poor. The large module area only determines the ceiling of its fingerprint performance, not the bottom line.
❸ Small-area fingerprint modules have higher requirements for MCU. With the continuous optimization of fingerprint recognition algorithms, the AA area of fingerprint modules may become smaller and smaller.
The more expensive of smart door lock, the better of user experience? That is wrong! Installation is the key.
For fingerprint locks, installation is an important link, which directly affects your later use experience and the service life of the lock. Sometimes some hidden dangers left over from the installation will directly cause the operation of the whole set of locks to be paralyzed.
For example, the position of the square steel hole is not large enough, so when the door is opened and the handle is pressed, it will be jammed. For example, the location of the fixing screw holes is not enough, and the front and rear panels will shift if they are barely installed, and the handle will also get stuck, and if it is more serious, the door will not be able to be opened.
Installation seems to be a very simple step. Just install the lock body into the door, and then install the front panel and rear panel. But often simple things, there are more and more strange things inside.
The hole position is the most important link in the lock installation. Problems caused by the wrong hole position are common, and the hole position is also the most easily overlooked step.
When installing, you must pay attention to supervising the installation master. The two positioning posts must be installed well, because the hole position of the positioning post will not exist on the old door before, so it is necessary to open a hole. Many installers will save trouble. It will not help you open the holes for installing the studs, so as to remove the two posts, it is useless to tell you, so you must pay attention to this point.
When installing, the gap around all the studs or square steel passing through the door should not be less than 5mm, because if the panel sags, it will definitely touch the door, resulting in jamming or unsmooth use. For fingerprint door locks, for mechanical locks, in addition to the positioning post, there is also a connecting line that passes through the door. This line is used to connect the front and rear locks to power on. The door hole of the old lock usually can only accommodate the size of a screw, so we must pay attention here, this place needs to be reamed.
Moreover, during the installation process, when tidying up the thread, the position of the thread end should not be too close to the active part. Once touched, there will be a risk of falling off or loosening in the long run. Usually this kind of situation will happen in the renovation of the old door, you don’t need to worry about the new door, because the holes of the new door are basically standard-compatible fingerprint lock holes.
After the installation is complete, it is enough to check whether the function of the lock is normal and whether the door is opened smoothly. When your hands are full of heavy objects or you are far away from home, you don't have to worry about the trivial matter of opening the door. When installed correctly, opening the door is a breeze.