Features of the display Xiaomi Redmi 9: full technical analysis + comparison with competitors

A smartphone screen is not just a picture glass, but a complex system of several layers, the quality of which depends on 90% of the user experience. Xiaomi Redmi 9, released in 2020, became one of the most popular budget smartphones due to the balance of price and specs. But what exactly lies beneath its 6.53-inch display? Why some users complain about dim colors, while others praise it for autonomy? And most importantly, how does this screen compare with analogues like the Redmi Note 9 or Samsung Galaxy A12?

In this article, we will analyze the technical specifications of the Redmi 9 display at the engineer level, test it in real conditions (sunlight, dark room, games), and give a checklist for fault diagnosis. If you are planning to buy, repair or just want to squeeze the most out of your device, here you will find the answers to all the questions.

Spoiler: The Redmi 9 display uses a IPS LCD BOE HD+ resolution [1600×720 display, but its real brightness is 20% lower than claimed due to energy-saving algorithms MIUI. This is not critical for everyday tasks, but may disappoint gamers or HDR- content enthusiasts.

Specifications of the Redmi 9 display: what hides the specification

On paper, the Xiaomi Redmi 9 screen looks standard for the 2020 budget segment, but the devil is in the details.

• 📏 Diagonal and aspect ratio: 6.53 inches, 19.5:9 (increased ratio due to "bangs" for the front camera).
• 🔍 Resolution: 1600×720 pixels (HD+), density ~269 ppi. For comparison, Redmi Note 9 has Full HD+ (2340×1080).
• 💡 Type of matrix: IPS LCD (manufacturer — BOE Technology, model NT36672C).
• 🌈 Color gamut: 70% NTSC (according to GSMArena), which is equivalent to ~95% sRGB.
• ☀️ Brightness: up to 400 nits (stated), real tests show 350-380 nits.
• 🔄 Update frequency: standard 60 Hz (without 90/120 Hz support).
• 🛡️ Protection: Corning Gorilla Glass 3 (not 5 like flagships!)

Key point: a matrix from BOE (not from Samsung or LG) means lower price, but less color stability when you change the viewing angle. For example, when watching a video from an angle of 45°, white can become bluish. This is not a marriage, but a feature of the budget IPS- panels.

Another feature is automatic color temperature adjustment in MIUI. By default, it is turned on and adds yellow for “eye comfort”, but this can be turned off in the settings (Ecran → Color Mode → Standard).

2.Pros and cons of Redmi 9 screen: an honest review

Let's break down the strengths and weaknesses of the display based on the testimonials and user feedback, and let's start with the pros:

• ✅ Large diagonal (6.53) with a compact body – convenient for watching videos and surfing the Internet.
• ✅ Good readability in the sun due to the matte coating (as opposed to glossy AMOLED).
• ✅ Low power consumption: IPS LCD consumes 15-20% less charge than AMOLED at the same brightness.
• ✅ Durability: No risk of pixel burnout (typical for AMOLED).

Now on the downsides - and here's something to be surprised:

• ❌ Low resolution (HD+) is noticeable when you look at text or small details in games, and the pixels are visible to the naked eye.
• ❌ Weak contrast: Black appears gray (typical for IPS), especially in dark scenes of movies.
• ❌ Always-On Display (due to IPS LCD) – you have to unlock your phone to see the time.
• ❌ A noticeable "soap film effect" when touching the screen (due to the air gap between the sensor and the sensor).

⚠️ Warning: If you plan to use Redmi 9 to view HDR- content (Netflix, YouTube), note that the screen does not support HDR10 or Dolby Vision.

For objectivity, compare Redmi 9 with the nearest competitors in the table:

As you can see, Redmi 9 loses Redmi Note 9 in resolution and brightness, but beats Realme C11 in color reproduction. If you are critical detail, you better look at the Note 9 or Poco M3 (with AMOLED).

3.How to check Redmi 9 display for broken pixels and defects

Before buying a used Redmi 9 or after the phone falls, you need to check the screen for defects.

1. Broken pixel test: 📱 Install the Dead Pixel Test app (available in the Play Market). 🔴 Run the monochromatic color test (red, green, blue, black, white). 🔍 Carefully examine the screen: the broken pixels will be visible as colored dots on a homogeneous background.
2. Backlight check: 🌓 Go to a dark room and open a black background (e.g., in Notes). ☀️ Increase brightness to maximum: uneven backlights will appear as gray spots.
3. Sensor Test: 🖐️ Use the Touch Screen Test app to check the responsiveness of all areas of the screen. ⚠️ Pay special attention to the edges, which often cause "dead zones" after falls.

Install Dead Pixel Test| Check for broken pixels (all colors)| Test backlight in the dark | Check sensor for responsiveness | Check case for cracks-->

If you find defects, evaluate their criticality:

• 🟢 1-2 bit pixels: no effect on work, you can ignore.
• 🟡 Uneven edge lighting: common IPS problem, but not critical.
• 🔴 Vertical/horizontal bands: sign of damage to the plume or matrix. Needs repair.
• 🔴 Pressed soap wiring: a defect in the adhesive layer between the sensor and the matrix, treated only by changing the screen.

⚠️ Warning: If after a fall, the Redmi 9 screen starts flashing or showing artifacts (colored stripes, ripples), immediately turn off the phone. This may be a short circuit in the plume that will damage the motherboard.

4. Comparison with Redmi 8 and Redmi Note 9: should you overpay?

Many users are faced with the choice: take the Redmi 9 or pay extra for the Redmi Note 9? or maybe save and buy the Redmi 8?

Conclusions:

• 📈 Redmi 9 vs Redmi 8: Redmi 9 has a bigger screen and better color reproduction, but the resolution is almost identical. It's only overpayable for the larger diagonal.
• 💰 Redmi 9 vs Redmi Note 9: Note 9 wins in all respects (Full HD, brighter, better matrix), but costs 30% more. If budget allows, take Note 9.

What about the AMOLED? In the Redmi 2020 lineup, only the Redmi K30 and Poco X3 got AMOLED- screens. If you're critical about black depth and contrast, look at these models.

5. Frequent Redmi 9 screen problems and how to solve them

Even the most reliable display can fail over time. Here's the TOP-5 of Redmi 9 screen problems and what to do about them:

• 🔄 The screen spontaneously turns on in your pocket Reason: high sensor sensitivity Solution: turn off "Raise to wake" in Settings → Screen → Lock and Protection.
• 🌡️ The screen dims when it heats up. The reason: overheating protection is triggered. Solution: Close the background apps and let the phone cool.
• 🖥️ Colored stripes or ripples Cause: damage to the plume or matrix Solution: only replacement screen (cost ~3,500–5,000 ₽).
• ☀️ Poor visibility in the sun Cause: low brightness of the matrix. Solution: turn on Contrast Amplifier mode in Settings → Screen → Reading mode.
• 🔋 The screen doesn't respond to touch, cause software failure or sensor damage. Solution: restart the phone. If it doesn't, check the plume.

⚠️ Warning: If Redmi 9 stopped recognizing touches at the edges after the screen was replaced, it's likely that the wizard used an unoriginal matrix, and in such cases, a re-replacement with sensor calibration is required.

To diagnose hardware problems, use service codes:

##6484## - Sensor Test (MMI-code for Xiaomi)
#4636## → “Equipment testing” → “Screen”

6.How to extend the life of the Redmi 9 screen: tips for care

The service life of the display depends not only on the build quality, but also on the operating conditions. Here are 7 rules to help avoid premature wear:

• 📱 Use a film and a case: even Gorilla Glass 3 is scratched by the sand in your pocket. We recommend oleophobic-coated films (fingerprints are less noticeable).
• ☀️ Avoid direct sunlight: IPS LCD burns out when exposed to UV for long periods.
• 🔋 Do not discharge the phone to 0%: at low charge, the screen controller can crash, leading to artifacts.
• 💧 Don't use alcohol for cleaning: it breaks down the oleophobic coating. Better use wet wipes for optics.
• 🎮 Limit the time of gaming sessions: prolonged load (e.g., PUBG or Genshin Impact) overheats the matrix.
• 🔄 Update: Newer versions MIUI often fix backlit and color-rendered bugs.
• 🛠️ Avoid cheap repairs: non-original screens from unknown manufacturers can have worse color reproduction and sensitivity.

💡

If the Redmi 9 screen starts to "glue" after a fall, but it looks whole, don't rush to change it. Try reconnecting the plume (this is free in service centers), in 30% of cases the problem is solved without changing the matrix.

To check the wear of the screen, you can use the AccuBattery application (shows the number of charging cycles) or the Throttling Test CPU (tests overheating).

7.Replacement of the Redmi 9 screen: cost and nuances

If the display does crack or stop working, you can replace it.

• 💰 The original screen costs 3,500–5,000 ₽ (depending on the region) and the non-original will cost 2,000–3,000 ₽, but you risk the worst color reproduction.
• ⏱️ Replacement time: 1-2 hours at the service center. Self-replacement is possible, but requires experience (you need to solder off the battery plume!).
• 🔧 What comes in the replacement: Matrix + sensor (they are glued together into one module); glue for fixation; new frame (if the old one is damaged).
• ⚠️ What to expect after replacement: Loss of leakage (dust/moisture can penetrate the screen) The sensor may require calibration (in settings: Settings → Additional → Screen Calibration).

Where to replace:

• 🏠 Official Xiaomi service: 6 months warranty, but 20-30% more expensive.
• 🔧 Local service centers: cheaper, but check reviews. Ask which screen is being put (original or copy).
• 🛒 Self-supported: only if you have experience.The replacement kit (screen + tools) costs ~2,500 ₽ on AliExpress.

💡

If after changing the screen Redmi 9 stopped vibrating or the speaker is not working - the wizard most likely damaged the flexible plumes.

FAQ: Answers to Frequent Questions About Redmi 9 Display