Xiaomi has officially launched its new Xiaomi Smart Door Lock 4 Pro, priced at $350 USD, bringing a mix of advanced AI technology and practical smart-home features.
Multiple Ways to Unlock
The lock supports 12 unlocking methods, including:
- AI palm vein recognition
- AI 3D face recognition
- AI fingerprint recognition
- Long-term, periodic, or one-time passwords
- Remote unlocking
- Mobile Bluetooth unlocking
- Emergency mechanical key
Unlocking with Xiaomi smartphones, smartwatches, fitness bands, and NFC-enabled door cards (sold separately)
AI Palm Vein Recognition
One of the standout features is the AI palm vein scanner, which uses near-infrared light to capture vein patterns beneath the skin. This allows for quick, touch-free unlocking in under a second, with a false rejection rate of less than 1%. Unlike traditional fingerprints, it works reliably even for the elderly with worn prints or children who struggle with height-based sensors.
AI 3D Face Recognition
The AI-powered 3D face recognition system simulates human eye parallax to map facial details, combined with live detection technology to prevent spoofing. It boasts a false rejection rate under 1%, an extremely low false acceptance rate (0.0001%), and near-instant unlocking at around 1 second.
Smart Security Features
The Xiaomi Smart Door Lock 4 Pro comes with a built-in smart peephole using a 24GHz millimeter-wave radar and AI motion detection. It can detect when someone lingers at the door, automatically recording and sending alerts. The 2MP ultra-wide camera (152°) supports a dynamic night vision system, switching between full-color in low light and black-and-white in total darkness.
A built-in HD display lights up whenever someone rings the doorbell and can also be manually activated to check outside at any time.
Quiet and Secure Locking
The lock features Xiaomi’s self-developed noise-reducing fully automatic lock body, which automatically secures the door once it’s closed. It uses a direct-insert C-grade lock core for enhanced protection against tampering.
It also provides a range of security alerts, including:
- Door not fully closed
- Door ajar
- Lock panel tampering
- Suspicious loitering
- Multiple failed unlock attempts
- Emergency fingerprint alerts (duress mode)
Smart Power System
Power is handled by a hybrid system:
One 5000mAh lithium battery (approx. 4 months of use per charge)
Four AA alkaline batteries (approx. 6 months of use)
When the lithium battery drains, the system automatically switches to dry battery power. The lock also issues reminders when battery levels drop to 5% or below. Both the inside and outside panels are equipped with dual Type-C charging ports for emergency power.
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