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Dead Pixel / Light Leak Check

Full screen colors to find dead pixels and backlight bleeding.

Black (1/10)
Check for light bleed
control
solid color
grid assist
Automatic carousel
Tip: Carousels are more suitable for “quick scans”. To accurately check for bad pixels, it is recommended to stop and search slowly using monochrome.
other
Note: Some browsers/systems do not support this or need to activate the page in the foreground to take effect.

How to use this page to find problems faster

• First click "Full Screen" and adjust the screen brightness to the level you want to compare (dark environment + medium-high brightness is recommended for light leakage).
• Dead pixels/bright spots: use red/green/blue solid color full screen, scan along the grid frame by frame; dead pixels often appear as "always black/always bright/color deviation".
• Light leakage/uneven backlight: Use a pure black or dark gray full screen, and observe whether there are shiny or cloudy patches on the edges/corners in a dark environment.
• Uneven color/dirty screen/ribbon: Use white/light gray/medium gray full screen to observe whether there is color cast, dirt, streaks or uneven light and dark.
• Tips: After full screen, you can "click the screen" to quickly switch colors; or use the space to start the automatic carousel and scan it quickly.

Inspection Guide

Use primary colors to find stuck pixels; Black/Grey for light leaks.

Step 1

Go to full screen and prepare the environment

about 10 seconds

Full-screen display with solid color background, it is recommended to select ambient light and brightness according to the target.

Click "Full Screen (F)" to enter full screen mode
Check for light leakage: dark environment + medium to high brightness recommended
Check for bad pixels: Moderate ambient light is enough to avoid interference from strong reflections
Step 2

Scan dead pixels and color casts with solid color

About 30–60 seconds

In solid colors such as red/green/blue, dead pixels are easier to identify.

Start with "red/green/blue", sweep one color and then change to the next one
Turn on the grid (G) and scan along the grid frame by frame to make it easier to miss.
After discovering an abnormality, pause the carousel and stop at the color recording position (such as the upper left/middle/lower right of the screen)
Tip: Some "bad pixels" are only noticeable under certain colors (for example, they are only dark under blue).
Step 3

Use black/grey/white to observe light leakage and uniformity

About 20–40 seconds

Black/grey is more suitable for seeing light leakage and uneven backlight; white/light gray is more suitable for seeing dirty screens and color temperature shifts.

Pure black: focus on the four corners and edges to see if there are obvious shiny/cloudy patches
Dark gray/medium gray: It is easier to see large-area uneven brightness, streaks, and vignetting
Pure white/light gray: Check whether there is a "dirty feeling", yellowish/blueish color, partial darkness or brightness

FAQ

A collection of frequently asked questions about dead pixels/light leakage/color uniformity inspection.

1.

What are dead pixels/bright pixels/dark pixels?

Bad pixels usually refer to pixels or sub-pixels working abnormally: bright spots (always bright), dark spots (always dark), or color casts (a sub-pixel failure causes abnormal color). The performance will be different under different solid colors, so it is recommended to use red/green/blue to check separately.

2.

Why use solid color full screen?

Solid colors can maximize the emphasis on "abnormal points" and "regional unevenness" on the screen. For example, black screens are most likely to see light leakage, white/grey screens are most likely to see dirty screens and uneven brightness, and RGB solid colors are most likely to see bad pixels and color casts.

3.

What is the grid used for?

The grid can divide the screen into regular areas, helping you scan in the order of "left to right/top to bottom" to reduce omissions; it also makes it easy to locate and record the location of the problem.

4.

How to measure light leakage more accurately?

It is recommended to use a pure black or dark gray full screen in a dark environment, and adjust the screen brightness to the mid-to-high range you usually use (or the level you want to compare). Be careful to differentiate between "normal IPS grey/glow" and distinct edge light leaks/cloudy patches.

5.

Full screen may fail on mobile phone/tablet, what should I do?

Some mobile browsers have limitations on the Fullscreen API (especially iOS Safari). You can still scroll the page to the maximum display area and manually hide the browser UI; or switch to a browser/desktop with better support and test again.

6.

Does this page collect my screen data?

Won't. The essence of "detection" here is to display a specific color/grid pattern to help you see it with the naked eye. All rendering is done locally in the browser, with no need to upload any images or device data.

7.

What to do after discovering bad pixels?

It is recommended to record the location (grid assist), review it in different colors, and take photos as evidence (be careful to avoid the influence of the camera's automatic exposure). If it is within the warranty/return period, you can communicate with after-sales accordingly.