If you've ever held a Xiaomi smartphone or a smart device of this brand, you've probably come across the term "scanner." But what exactly is behind that word? In the Xiaomi ecosystem, "scanner" can mean a whole range of technologies, from biometric sensors in smartphones to laser sensors in robot vacuum cleaners. This article will help you understand what kinds of scanners the company uses, how they work, and why the user needs them at all.
The scanners in Xiaomi devices are not just a marketing ploy, but real-world technology solutions that simplify everyday tasks. For example, a fingerprint scanner in a smartphone unlocks the screen in a split second, and a laser scanner in a robot vacuum cleaner Mi Robot Vacuum builds a map of the room with millimeter accuracy. However, not all scanners are equally useful: some models are outdated, others work only with certain software. We analyzed current devices from 2023-2026 and identified key points that you should know before buying or setting up.
It is important to understand that the term “scanner” in the context of Xiaomi can refer to:
- 📱 Biometric sensors (fingerprints, facial recognition)
- 🤖 Laser/Infrared Sensors in Robot Cleaners
- 📄 Document scanners in applications (e.g. Mi Scanner)
- 🔍 QR/Barcode readers in smartphones and tablets
Types of scanners in Xiaomi devices: a full review
Xiaomi's ecosystem includes more than a dozen types of scanners, but for the average user, only 4-5 basic ones are relevant.
1. Fingerprint scanners are the most famous type found in almost all of the brand’s smartphones since the Redmi Note 3 (2016). Current models (such as the Xiaomi 14 Pro or POCO F6 Pro) use ultrasonic or optical scanners hidden under the display. They are not only faster than traditional capacitive sensors, but also less prone to wear. However, they have a disadvantage: at low temperatures (below +5 ° C), recognition accuracy can fall.
Laser scanners (LiDAR) – used in robot vacuum cleaners (Mi Robot Vacuum-Mop 2 Pro, DreameBot) Z10 Pro) and some smart lamps: these sensors emit laser beams and measure the time they reflect off obstacles, creating a light-based lighting system. 3D-The main advantage over infrared sensors is high accuracy (accuracy up to 2 mm) and the ability to operate in complete darkness.
Document scanners and QR-Codes are software solutions integrated into the smartphone camera. For example, the Mi Scanner app (available from the Mi App Store) allows you to digitize documents with automatic perspective alignment and improved contrast. QR smartphone-notification MIUI It recognizes codes in 0.3 seconds, faster than many specialized applications.
4 Infrared scanners are found in Mi Remote remotes, some models of robot vacuum cleaners (Mi Robot Vacuum 1C) and smart lamps. They are cheaper than lasers, but less accurate: the error can reach 5-10 cm, and in bright sunlight, the sensors sometimes go blind, but consume minimal energy.
How does the fingerprint scanner in Xiaomi smartphones work
The fingerprint scanners in Xiaomi smartphones have evolved from mechanical buttons to completely buttonless under-screen solutions. Let's take a look at how they work and how they differ.
Capacitive scanners (until 2018) are the simplest and most reliable, and they read the topography of a finger through microscopic capacitors on the surface of the sensor, like the Redmi 5 Plus or Mi A1, minus physical contact, and if the glass surface is damaged, the sensor can fail.
Optical scanners (2019-2022) use LED backlight and a miniature camera under the screen. The scanner takes a picture of a finger and compares the image to a stored pattern. Examples: Xiaomi Mi 9T Pro, POCO X3 Pro. Plus, work even with wet or dirty fingers. Minus is less safe, because in theory you can fool a high-quality fingerprint photo.
Ultrasonic scanners (since 2022) are the most advanced, sending ultrasonic waves through the display glass and analyzing the reflected signal, creating a reflection signal. 3D-Used in flagships: Xiaomi 13 Ultra, Mix Fold 3. Advantages: high accuracy (error 1 in 50 000), working through a protective glass or film).
| Type of scanner | Xiaomi models | Recognition speed | Level of security | Cons |
|---|---|---|---|---|
| Capacitive | Redmi Note 7, Mi 8 Lite | 0.5–0.8 s | Medium. | Wear of mechanical button |
| Optical | Mi 10T Pro, POCO F3 | 0.3–0.5 s | Low. | Vulnerable to fingerprint photos |
| Ultrasonic. | Xiaomi 14, Mix Fold 2 | 0.2-0.3 s | High-pitched | Expensive repairs |
⚠️ Note: If the fingerprint scanner on your Xiaomi smartphone stops working after falling or getting moisture, don’t try to disassemble the device yourself. 90% of the time, the problem lies in damage to the flexible plume that connects the sensor to the motherboard. Contact the service center – repair will cost less than replacing the entire display module.
Laser scanners in Xiaomi robot vacuum cleaners: the principle of operation and setting
Xiaomi’s robot vacuum cleaners, such as the Mi Robot Vacuum-Mop 2 Pro or DreameBot L10s Ultra, use LiDAR laser scanners to navigate, rotate at 300 to 600 revolutions per minute, emitting laser beams and recording their return time, and build a 2 to 5 mm map of the room based on this data.
The advantages of laser scanners over infrared:
- 🎯 Accuracy: Determines furniture, chair legs and even wires on the floor.
- 🌑 Working in the dark: not dependent on lighting.
- 🗺️ Multi-room map: saves up to 5 floors with markup of cleaning areas.
However, there are also disadvantages:
- 🔋 Increased power consumption: laser module consumes ~15% charge per hour of operation.
- 💰 Expensive: LiDAR robots are 30-50% more expensive than models with infrared sensors.
- 🚫 Limitations: Cannot see transparent surfaces (glass tables) and mirrors.
To set up a laser scanner in a robot vacuum cleaner, follow the following steps:
Download the Mi Home app|Add the device through QR-code|Start the first cleaning in manual mode|Check the map in the application and adjust the zones|Save the map and set up a schedule-->
⚠️ Attention: If the Xiaomi robot vacuum cleaner has started to “lose” or build a map with errors, check the purity of the laser module. Dust or spider webs on the lens can distort the signal. Wipe the sensor with a soft napkin dipped in alcohol (no more than 70.
Document scanner in Xiaomi smartphones: how to use and what are alternatives
The document scanning feature in Xiaomi smartphones is implemented through the standard Camera app (Document mode) or specialized Mi Scanner software, which allows you to digitize papers, business cards, checks and even pages of books with automatic quality improvement.
How does the document scanner work:
- Open the Camera app and select Document Mode (or Professional → Scan in older versions of MIUI).
- Point the lens over the document – the smartphone will automatically find the boundaries and take a picture.
- The application will cut off extra fields, straighten perspective and improve contrast.
- The finished file can be saved as PDF or JPEG, and sent to the Mi Cloud.
For more advanced tasks (OCR-recognition of text, mass scanning), it is better to use third-party applications:
- 📑 CamScanner - Supports OCR 200+ languages, but requires a subscription to export to PDF.
- 📄 Adobe Scan – Integration with Adobe Acrobat for editing PDF.
- 🤖 Google Drive – built-in scanner with automatic saving to the cloud.
How to Improve the Quality of Manual Scanning
Scanners. QR-codes: hidden functions in MIUI
Scanner. QR-codes in Xiaomi smartphones hidden in the curtain notifications (image icon) QR), But what few people know is that he can do a lot more than just open links:
- 🔗 Create your own QR-codes for Wi-Fi, contacts or text (long tap on the scanner icon).
- 💳 Read bank cards (in some regions) for quick payment via Mi Pay.
- 🎫 Save tickets (aircraft, movies, concerts) in Mi Wallet right from the scan.
- 📡 Connect to Xiaomi smart devices (lamps, sockets, vacuum cleaners) without entering a password.
To activate the advanced functions of the QR scanner:
- Open the Settings. → Annexes → Scanner. QR-code.
- Enable the Create QR and Scan History options.
- To work with payments, add a bank card to Mi Pay (Settings → Wallet & Payments).
💡
If the scanner QR-If you don't recognize the code from the screen of another device, try to reduce the brightness of the display to 50-60%. Too bright light can "clog" the camera sensor.
Frequent problems with Xiaomi scanners and how to solve them
Even the most reliable Xiaomi scanners sometimes fail, and we've collected typical problems and ways to fix them without going to the service.
1. The fingerprint scanner doesn't recognize the finger.
- 🧼 Wipe the sensor and finger with a dry wipe (fat or moisture interferes with reading).
- 🔄 Reboot your smartphone – sometimes resetting temporary sensor data helps.
- 🆕 Remove the old print and add a new one to Settings → Passwords and security → Fingerprint.
- 🔧 If the sensor is under the screen, check the integrity of the protective glass – cracks can block the signal.
2. Robot vacuum cleaner doesn't build map or 'lost'
- 🧹 Make sure there is enough lighting in the room (even for LiDAR).
- 🔦 Wipe the laser module with a soft brush (dust distorts the signal).
- 📱 Update the firmware of the robot through the Mi Home app.
- 🚪 Close doors to other rooms – drafts can knock navigation.
3.Scanner. QR-codes are down
- 📸 Check the permissions for the Camera app in Settings → Annexes → Permits.
- 🔍 Turn off the energy-saving mode for the camera.
- 🗃️ Clear the camera cache in Settings → Annexes → Camera. → Warehouse.
- 📱 If the problem persists, try a third-party app (e.g, QR & Barcode Scanner).
⚠️ Note: If after the update MIUI The fingerprint scanner stopped working, don't try to roll back on the old firmware version - this may block the bootloader. → The phone. → Resetting settings, previously saving data.