What is White Uniformity Issue
When reading a web-page that has black text on white background if you notice that the white background color looks different at different parts of the screen, its called white uniformity issue.
The white may look slightly bluish (cooler) in some areas and slightly yellowish (warmer) in other areas.
Simply put, the shade of white is not uniform across the entire screen.
This non-uniformity is noticeable only when reading a page with black text on white background.
When viewing a full screen pure white image, this issue may not be that noticeable even though it exists.
I have used 2 IPS monitors so far and both of them had this issue. One of AOC I2080SW and another was LG 22MK600. In both the monitors half the screen was showed pure white color with a bluish shade and the other half with a yellowish shade.
The surprising thing about this issue is that other colors will render very uniformly. For instance if you display full screen image with pure red, or green or blue colors, they will appear very consistent across the entire screen.
Only when you display black text on a full screen white background does the problem become clearly visible.
To test your own display here are a few free online tools:
1. http://www.whitedisplay.com/ - This website fills the entire screen with a single color so that you can see if there are any variations in the color rendering.
2. https://lcdtech.info/en/tests/dead.pixel.htm - Similar to the above website.
3. https://www.eizo.be/monitor-test/ - This tool can run multiple tests for your lcd monitor like response time test, uniformity, dead pixel etc.
Most of the times the difference in shade is very slight that it is be easy to ignore and continue working normally and sometimes it can be significant causing severe discomfort.
However for professionals doing photo editing even the slightest difference in the shades of white can be very annoying and problematic.
In this article we shall discuss about what causes white uniformity issues, and how to deal with them and avoid them when buying a new monitor.
What causes white uniformity problems
1. Poor Quality Control
According to experts, uniformity issue happens due to uneven backlighting which is a result of poor quality control and relaxed tolerance checks during manufacturing.
It is believed that most IPS display panels have the uniformity issue to varying degrees, and cheap ones have it much worse.
In simple words, manufacturers don't adhere to strict quality control process and checks to help them reduce costs.
This results in imperfections like inconsistent colors or backlighting. Other related problems are backlight bleeding and ips glow, which are reported often by users.
2. Drawbacks of Thinner and Bezel-less design
Furthermore, manufacturers are constantly trying to increase the aesthetic appeal of the monitors by making them thinner, slimmer and smaller which leaves lesser space for the internal hardware components leading to more quality and performance issues.
LCD panels are a complex technology and there are lots of sophisticated pieces of hardware packed into the screen of a monitor. To make the monitor slimmer the panels are made thinner which cause inconsistencies to show up and difficult to tackle.
Majority of the regular consumers are often attracted by the external looks of a monitor and don't notice the flaws in the on-screen display quality. This gives the manufacturers an easy market to tap into.
For the quality conscious consumers (who are fewer in number) who complain, the brands would simply provide a replacement. So they are able to keep everyone happy and satisfied.
Working with white uniformity issue
Compared to other display problems, the white uniformity issue is least troubling.
It is most noticeable up only when reading a black and white document and often times its easy to ignore and continue working.
On the positive side, when viewing images, watching videos or playing games, the problem is completely un-noticeable even if you know its there. This is why most people aren't really bothered with this problem even if they can spot it.
However if you are a graphics designer or animator then you will find this problem a point of concern because colors will appear very different from their true appearance. Depending on how serious your work is, you may be able to compromise or just get another monitor.
Can it be fixed ?
There is nothing users can do about it, because it is a problem in the hardware of the monitor. However it might be possible to slightly reduce the color difference by changing the settings of the monitor.
The most common technique is to reduce the Red and Green component and increase the blue component in the color settings of the monitor. Changing the brightness and contrast may also have an effect on making the non-uniformity less visible.
However these techniques will only have limited affect and do not solve the underlying fault in the hardware.
How to avoid white uniformity problem
If you have already purchased a monitor that has this problem, there is nothing much that can be done besides getting it replaced or refunded. However when buying a new monitors there are certain key things to keep in mind to increase your chances of getting a good display that is less likely to have such problems.
These suggestions are based purely on user feedback and there is no real correlation of these points with monitor quality.
1. Budget monitors or commonly called cheap monitors tend of have color uniformity issues because of poor quality controls and relaxed tolerance checks during manufacturing process.
When selecting a monitor you may want to avoid those models that offer too many features at a very low price points. Adding more features without increasing the price will likely have compromises made in other places, the most common being the display quality.
2. High spec monitors that offer higher refresh rates (over 60 hz) and faster response times (below 14ms), might have color uniformity problems since they are designed in a way so that pixels can rapidly change their color, brightness and other properties.
Due to the rapid changing process quality factors like color consistency and uniform backlight might be affected. It is better to buy a monitor with fewer fancy features and thicker bezels, as they are likely to have better checked hardware.
Conclusion
Have you even faced a similar problem with a brand new monitor ? Let us know your thoughts in the comments below.
Here are some more stories reporting and discussing white uniformity issues:
https://forums.tomshardware.com/threads/does-all-budget-monitor-has-white-uniformity-issue.3620538/ https://www.dpreview.com/forums/thread/4499746 https://community.acer.com/en/discussion/547117/white-uniformity-issues-do-you-have-them-too-did-you-check https://www.reddit.com/r/Monitors/comments/dkker6/white_uniformity_issue_aoc_ag271qg/
You can also use White screen to test dead pixel
Check that there are no pixels that are burnt (dull) or stuck to a single color. Also check, with the help of this site check out https://www.whitescreen.org/ , that the brightness of the screen is homogeneous and that there are no areas noticeably lighter or darker than the others.