Location of fingerprint scanner on Xiaomi smartphones

Xiaomi’s current smartphones and Redmi and POCO sub-brands come with different biometric protection systems. Depending on the price segment and year of the device’s release, the recognition sensor can be located in completely different locations in the case. Users who are first exposed to the Chinese ecosystem often look for a physical button where there is none, or do not notice the sensor built into the screen.

Determining the type of scanner is critical to the initial setup of the gadget. If you don't activate biometric protection right away, the system may require you to enter a password every time you turn on. In this article, we'll look at all the possible sensor locations, from the classic buttons on the back to the advanced ultrasonic modules.

Don't panic if you don't see an obvious round or rectangular element on the end or back of the device. Technology has gone a long way, and manufacturers have learned to mask sensors as design elements or integrate them directly into the display. Understanding the logic of placement will help you quickly find the right item.

Classic rear scanners: a bygone era

In models released between 2016 and 2019, the dominant standard was the placement of a fingerprint module on the back cover, usually a round or oval button located just below the main camera block. On budget models of the Redmi Note series of the time, the sensor was often combined with the brand logo.

Physically tapping a scanner can serve as a home button or as a media player, but with the rise of frameless designs and the increase in screen size, engineers have had to find alternative solutions, and the rear position is no longer convenient for unlocking with one hand in an upright position.

💡

If the rear scanner doesn’t respond, try changing the angle of touch slightly or rubbing the sensor area and finger from moisture – the oxide film often interferes with reading.

One important thing that should be considered for owners of back-scanner devices is that mechanical buttons tend to wear out, and over time, clicks can become less clear, and tactile returns in these models are the main indicator of successful reading, so it is important to feel the moment of activation.

Side scanners: standard for modern models

By far, the most common solution for mid-range and flagship smartphones is the side scanner, which is integrated directly into the power button, which is on the right end of the case. It looks like a normal button on the outside, but the top of it has a characteristic glossy or textured rectangle.

You don't have to push the key hard to unlock, like you did with mechanical analogs, and you just have to touch the reading zone with your finger, while you're holding it or lying on your desk, and this solution is called side-mounted fingerprint, and it's become the gold standard for this. LCD-screens that do not support subscreen technology.

It's important to note that on some models, like the POCO X3 series or the Redmi Note 10, the power button can be recessed a little or protruded, and this is done for ease and finger-finding. If you can't unlock your phone, make sure you touch the top of the button, not the middle of it.

Subscreen sensors: technologies of the future

Xiaomi’s flagship models, such as the Mi 11 series, Xiaomi 13 and 14, and some versions of the Redmi K, feature optical or ultrasonic scanners hidden under the display. Visually, they are not found when turned off. The active zone is usually indicated by a barely noticeable fingerprint icon at the bottom of the screen when the device wakes up.

The way an optical scanner works is to illuminate the area under your finger with bright light and read the reflected image of a papillary pattern. Ultrazoose sensors, which are less common and more expensive, use sound waves to create sound waves. 3D-Finger card that works even with wet hands.

⚠️ Warning: When you put a security glass on phones with a scanner under the screen, be sure to choose accessories marked "Fingerprint Friendly." Thick glass or improper glue can completely block the sensor from working.

If you want to get a scanner under the screen, you need to press your finger a little bit tighter than the side sensor, and you need to read the reflection through the display matrix, and if you're slow to unlock, try to increase sensitivity or recreate the fingerprint.

Comparison of scanning technologies

The differences between sensor types affect not only usability, but also the speed of unlocking and data security. capacitive sensors, which are used in the side and back buttons, are considered very reliable and fast. They read the electric charge of the finger.

Optical subscreen solutions are evolving faster, but can still yield in speed in bright sunlight. Ultrazooch modules are devoid of this drawback, but significantly increase the cost of the device. Below is a table for comparing performance.

The choice between these technologies is often dictated by the design of the smartphone. If you care about top speed and you often use your phone with gloves (although biometrics on Xiaomi usually does not work in gloves), then a classic capacitive scanner may be preferable.

Sensor setting and calibration

Once you have found where your fingerprint is on your Xiaomi, you need to set up the system correctly. Go to the Settings menu, select Password and Security, and then Fingerprints. PIN-backup.

When you add a fingerprint, try to touch the sensor with different parts of your finger, not just the center, which will improve the accuracy of recognition in the future. The learning algorithm will remember the edges and complex curves, which will allow you to unlock the phone even if you are not fully applied.

In modern MIUI and HyperOS shells, Advanced Mode is available, which makes the scanner work constantly, without going to sleep mode to save energy, which speeds up the response, but this can slightly increase battery consumption.

Solving recognition problems

Sometimes users are faced with a situation where the phone stops seeing the finger, often because of contamination of the surface of the sensor or screen, fat spots, hand cream or sweat can distort the signal, regular wipe of the scanning area with an alcohol wipe solves 90% of the problems.

If mechanical cleaning didn't work, there may have been a software failure of security, in which case it's recommended that you delete all the fingerprints you saved and add them again, and don't try to add the same finger twice under different names, because it confuses the system's database.

⚠️ Warning: Never use sharp objects or aggressive chemicals (acetone, solvents) to clean the scanner opening, which may damage the sensor's protective glass or impair its sensitivity.

In rare cases, the problem may be hardware, because if the phone falls or is exposed to moisture, the plume of the scanner may have moved away, and in such situations, the software methods are powerless, and the intervention of a specialist service center is required.

💡

Properly adjusting your fingerprint from different angles of your finger increases unlocks by up to 98%, even in the dark or when your hands are shaking.

Security of biometric data

Many users worry about where their fingerprints are stored, and Xiaomi smartphones store this information in an isolated, secure TEE (Trusted Execution Environment) module, which is not transmitted to the company's servers, is not synchronized with the cloud, and cannot be read by third-party applications.

Even when you reset your settings to factory settings, your fingerprints are permanently deleted, which provides a high level of privacy, but it is worth remembering that biometrics can be faked (albeit difficult), so accessing banking applications often requires additional information. PIN-code.

Using a fingerprint scanner is a balance between convenience and security: Understanding how your particular sensor works makes the most of your smartphone’s capabilities. Don’t ignore this tool, as it protects your personal data from outside access.