What is the hole on the Xiaomi phone: a full analysis of functions

Owners of Xiaomi, Redmi and Poco smartphones often notice small, barely distinguishable holes on the device body. They are usually located on the upper edge or next to the main camera, and many users immediately wonder about their purpose. Some people fear that this is an assembly defect or a place for a hidden camera, while others simply ignore them, unaware of the important role in the work of the gadget.

In fact, these holes are critical design elements that modern smartphones would not be able to provide high-quality communication and sound recording, and they are dictated by the need to integrate complex acoustic systems into a thin body, and in this article we will examine in detail which modules are hidden behind these holes and why they should not be closed.

Understanding the functionality of these elements will not only help you to understand the technology better, but also to avoid common errors in operation, such as blocking microphones with covers or damage to IR emitters. We will look at the technical aspects of noise reduction and control of household appliances that hide in these miniature holes.

Main microphone and noise reduction system

The most common "hole" you can find on the top or bottom of a smartphone is the secondary microphone hole. While the main conversation microphone is usually located at the bottom (to be closer to the mouth), the top microphone performs an auxiliary but vital function.

The system works by comparing the sound patterns that both microphones hear, the main one picks up your voice and the surrounding noise, and the top one only picks up the surrounding noise, and the processor analyzes the difference in signals and programmatically subtracts the background sounds, leaving the clear voice of the interlocutor.

⚠️ Warning: If you notice that you are not heard well during a conversation or that your voice sounds like a barrel, check if the upper hole is clogged with dust or pile from your pocket.

Xiaomi’s current flagship models use advanced algorithmic processing to work efficiently even in windy weather.Without this additional opening, communication quality in noisy places like the subway or busy streets would be significantly worse.

It's important to understand that the microphone hole is often covered by a special mesh that protects the insides from getting particulate matter, but over time, this mesh can become contaminated, which leads to a decrease in the volume of recording when shooting video in a horizontal position when both microphones are working for stereo sound.

Infrared port for technical management

One of the unique features of many Xiaomi and Redmi smartphones is the integrated infrared port (IR Blaster), a small black speck on the top of the case that is often mistaken for a regular microphone or sensor, which turns your phone into a universal remote control.

The technology allows you to transmit signals to household appliances: TVs, air conditioners, audio systems and consoles. To work, you use the standard Mi Remote application (or Mi Remote), which is already pre-installed in the shell of MIUI or HyperOS. You do not need additional adapters or bluetooth bridges.

Unlike Bluetooth or Wi-Fi, infrared radiation requires a line of sight or close distance to the receiver, as it is a light signal in the invisible spectrum, but this ensures high compatibility with devices of different years of release, even with very old models of technology released decades ago.

Users often underestimate this feature, but it's incredibly convenient in the home: Imagine if you had to turn off the TV and the remote was lost, or if you had to set up an air conditioner that was hard to reach, the smartphone solved these problems instantly.

• 📺 TV control: channel switching, volume and brightness adjustment.
• ❄️ Air conditioning setting: temperature selection, blowing mode and timer.
• 🔊 Audio systems: management of music centers and saunbars.
• 📡 Prefixes: navigation on the menu of digital receivers and IPTV.

Approximation and illumination sensor

Another group of holes, often located next to a speaker on the front or in a narrow frame on the top, are optical sensors: proximity sensors and light sensors, which look like small black dots that can be hidden under the display glass or displayed in separate holes.

The approach sensor is activated when you hold the phone to your ear while you're talking, and its task is to turn off the screen so that the cheek doesn't get hit by random buttons (call reset, loudspeaker switch on), and if that hole is contaminated or covered by a protective film, the screen can go out on its own or, conversely, not respond to the face.

The light sensor measures the intensity of the outside light and automatically adjusts the brightness of the display, which saves battery power in the dark and ensures that the picture is readable in the bright sun, and the sensor is not working properly, which leads to the screen either blinding at night or not seeing anything during the day.

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If the proximity sensor is not working properly, try to wipe the top of the screen with an alcohol wipe. Often, greasy spots from conversations block the sensor.

In some models with type screens AMOLED These sensors can be embedded directly under the display, and you can't see the external holes for them. IPS-matrices often require physical slots in the body or frame.

Comparison of the location of holes in different series

The configuration of the holes on the case is highly dependent on the specific series of smartphones and the year of its release. Xiaomi engineers are constantly changing the layout to make room for more capacious batteries or new camera modules. Understanding these differences will help you identify the purpose of a particular element faster.

For example, in the Redmi Note series, the IR port often takes up space on the upper end, while in the flagship Xiaomi Mi or Xiaomi 13/14 series, it can be moved or removed altogether, replacing it with a stereo speaker. The number of microphones also changes: in top models, there can be three of them for recording zoom video.

As you can see from the table, the presence of an IR port is a hallmark of most mid- to high-end devices from this manufacturer, and ultra-flagships sometimes sacrifice this module for the sake of higher-end moisture protection or reducing the thickness of the frames.

It’s also worth noting that some gaming smartphones, such as Black Shark (a sub-brand of Xiaomi), may have additional holes for active cooling or external controllers, making them unique.

Additional sensors and rare functions

In addition to basic features, some models also feature specialty sensor holes, such as the Flicker sensor that appeared in some flagships, which measures the flicker frequency of light sources so that the camera can take better pictures in artificial light.

This sensor helps avoid the streaks in photos that often occur when shooting in rooms with fluorescent lamps, and it works in tandem with the main camera module, transmitting data on the frequency of alternating current in the power grid.

⚠️ Warning: Do not attempt to clean sensor holes with sharp metal objects such as needles or paper clips.You may damage the sensitive microphone membrane or scratch the IR emitter lens.

Also, there may be process holes in the design that are only necessary during the assembly phase or to equalize the pressure inside the housing as atmospheric pressure changes, and they do not carry a functional load for the user, but their presence is due to engineering requirements.

In rare cases, users confuse the holes with the places to install additional SIM-cards or memory cards, if the tray is made in a non-standard format. However, in modern Xiaomi smartphones, all slots are usually combined into one tray on the bottom or side end.

Maintenance and protection against pollution

Regular maintenance of holes is the key to a long and stable operation of your Xiaomi. Dust, down from clothes, street dirt and skin fat tend to accumulate in these nodes. Over time, this can lead to a quiet recording sound, a idle remote control or failures of the proximity sensor.

The best way to clean is to use a soft, antistatic brush or pear to purge, and you can use a sticky tape (scotch) carefully, gluing it to the hole and ripping it off abruptly to pull out the dust. The use of liquids is only permissible in minimal amounts and with great care.

It's also important to look at protective cases. Cheap silicone cases often have inaccurate cutouts that overlap part of the microphone or IR port. If the quality of communication has decreased after buying a new case, look at its design.

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Regular but careful cleaning of the holes every 3-4 months prolongs the life of the acoustic system and sensors of your smartphone.

If you notice someone complaining about an echo or a quiet voice, and you only hear one side of the sound when you're recording it, it's probably the clogged hole in the microphone that's the problem, and cleaning it up in a timely manner will bring back the factory performance.

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