A monitor is not the last thing to look for when buying or using a computer or laptop for a long time. After all, the quality of the image and the comfort of the perception of the picture by you will depend on it.
Today, almost all monitors use the RGB color model for color reproduction - from the English Red, Green, Blue. There are three channels in each pixel of the screen - one is responsible for red, another for green, and the third for blue. Mixing at different intensities, they produce different colors - the maximum intensity of all three colors gives white, the minimum intensity - black.
With the help of special pictures, you can check the presence of dead pixels on the screen of a computer, laptop or TV, color rendition, smooth transition between colors, sharpness, contrast and brightness.
In this article I will tell you how you can check the monitor for dead pixels using special online tests.
Monteon test
With this test, you can check not only the computer screen, but also the display of a mobile device.
In the address bar of your browser, type monteon.ru. To start testing, click "Start", if you want to read more about tests, click "Learn more about tests".
This online test provides various test screens to help you evaluate the image displayed on the monitor. For a full check, go to full screen mode... The arrows can be used to change the test pictures. You can also select the required tests on the control panel. If you do not move the mouse, the control panel disappears and does not interfere with checking the monitor.
Check the monitor for defective pixels can be done using the red, green and blue test images presented in the section "Color rendering"... Images of other colors are also presented there.
To do this, take a close look at each image presented on the screen. It shouldn't have black pixels. If, for example, in red, you find such pixels, this means that the channel responsible for the red color is not working, and such a pixel can be called dead or broken. Accordingly, at such a point, you will not be able to get a magenta color - mixing red and blue, and the color reproduction of this pixel will be distorted.
Using the monteon test, you can also check the screen for smooth transition between colors - "Gradients", alternation of black and white pixels - "Flicker", sharpness of the image and clarity of borders for the text displayed on the screen - "Sharpness", brightness, contrast and more.
In the description of the test, you can read in more detail what flaws should be looked for for each image.
Tft.vanity.dk test
Type tft.vanity.dk into the address bar of your browser, the following site will open. To check the monitor online, click on the "HTML window" link. If you want to check any other computer, laptop or TV that is not connected to the Internet, follow the link "Executable mode", download the executable file to a USB flash drive and run it on any other device.
When you move the mouse cursor to the top of the window, the main menu appears, represented by seven tabs. If the window of prompts on the screen bothers you, turn it off with the "Info on / off" button.
The Main page tab contains various shades of gray. Here you can evaluate how your monitor distinguishes close shades: if there are noticeable differences between shades with a difference of 2%, then the monitor is good.
On the "Color range" tab, you can evaluate the monitor's reproduction of various colors and the smoothness of the transition between shades. Here you can also see the smoothness of the gradient from black to white, red, green, blue. If you do not see any distinct stripes, then the monitor is fine.
On the "Trailing" tab, you can estimate how blurry objects of a certain color will be in motion. If a loop remains behind the test square, it's not a big deal. But the longer it is, the worse the monitor is.
To start moving the square, click "Start box". Its speed can be increased or decreased with the "Speed" button. If you want to move it to a different strip, click on the small squares in the "Background color" area. To change the shape and color of the square itself, move the sliders in the "Box color" field.
On the "Homogenuity" tab, you can check the monitor for dead pixels. Change the test images, represented by black, white, red, green and blue images, and see that the screen is filled evenly. If the colors are displayed normally on the whole screen and there are no black pixels, for color pictures, then there are no dead pixels on your monitor.
The 1: 1 pixelmapping tab is great for checking TV screens. This fills the screen with alternating black and white dots. There should not be consecutive pixels of the same color or colored pixels.
On the "Text" tab, you can see the display of a certain color of text on any background. The edges of the text should not be blurry.
I will end on this. I think now you know how to check your monitor for dead pixels, and more.
Rate article:If you want to exchange an already purchased monitor with dead pixels, then keep in mind that there is an international standard ISO 13406-2 regulating the permissible amount defective pixels on the LCD monitor. Thus, the seller may refuse to exchange the monitor or refund you if the number of defective pixels is in.
1Number of defective pixels on the monitor
The number of faulty pixels allowed depends on the display class (pixel fault class). The ISO 13406-2 standard distinguishes four classes: first does not allow for defective pixels. As a rule, all modern LCD monitors refer to second class... Below you can calculate the number of pixel defects allowed in accordance with the ISO 13406-2 standard for monitors. second class:
|
Note... In the calculation, the fractional number of defective pixels is rounded to the nearest integer by discarding the fractional part.
The ISO 13406-2 standard identifies the following defects: permanently lit white pixels (type I), permanently unlit black pixels (type II), subpixel defects (type III), which appear as colored permanently lit / unlit pixels of the primary colors (red, green , blue, cyan, magenta, yellow).
In addition, for a resolution of 1 million and higher, it is allowed to accumulate color defective pixels (type III) side by side in a 5 x 5 pixel square. Such a defect is called a cluster. Second class monitors does not allow the presence of 5 x 5 clusters with defective pixels of type I or II. For more details see.
In practice, such a large number of Defective pixels as specified in ISO 13406-2 are extremely rare. The wide tolerance can be explained by the fact that the standard was developed in 2000. Since then, the technology for producing liquid crystal panels has undergone improvements.
2How to check the monitor for dead pixels
Examination LCD monitor on presence of defective pixels consists in carefully examining the screen to identify abnormal pixels. Inspection is carried out sequentially for the primary colors: black, white, red, green, blue, cyan, magenta and yellow.
When buying a monitor for a PC or laptop, the quality and condition of the display is by no means the last thing to pay attention to. This statement is equally true when the device is being prepared for sale. One of the most unpleasant defects, which very often can simply not be detected at a cursory examination, is the presence of dead pixels.
To find damaged areas on the display, you can use special programs such as Dead Pixel Tester or PassMark MonitorTest. But in some situations, for example, when buying a laptop or monitor, installing additional software is not the most convenient solution. However, with the availability of access to the network, web services come to the rescue for testing the quality of the screen.
Of course, none of the software tools on their own can detect any damage on the display. This is understandable - the problem, if any, lies in the "iron" part of the apparatus without appropriate sensors. The principle of operation of solutions for checking the screen is rather auxiliary: tests consist in "filling" the monitor with various backgrounds, patterns and fractals, allowing you to independently determine if there are prominent pixels on the display.
“Well,” you might think, “it’s not difficult to simply find homogeneous pictures on the Internet and check them with their help.” Yes, but there is also nothing difficult in special online tests and they are more indicative in assessing defects than ordinary images. It is with such resources that you will get acquainted in this article.
Method 1: Monteon
This tool is a complete solution for calibrating monitors. The service allows you to thoroughly check various parameters of PC displays and mobile devices... There are tests for flicker, sharpness, geometry, contrast and brightness, gradients, as well as screen color rendition. It is the last item in this list that we need.
The service developers recommend testing in a dim or darkest room, since it is in these conditions that it will be easier for you to detect a defect. For the same reasons, you should disable any monitoring software for the video card, if any.
Method 2: CatLair
A simple and convenient website for finding dead pixels, as well as minimal diagnostics of monitors for desktop and mobile devices. Among the available options, in addition to the one we need, there is the possibility of checking the display's synchronization frequency, balancing colors and "floating" the picture.
For each test, the service offers detailed description and a hint of what to look for. As for convenience, the resource can be used without any problems even on smartphones with very small displays.
When purchasing a computer, we pay more attention to one part of it - system unit, decreasing the significance of the other - the monitor. But a flawlessly functioning monitor, configured in the right way, is very important not only for maintaining visual acuity, but also for a comfortable pastime at the computer. It is important to check how the monitor works, both before purchase and during use for its correct setup.
There is usually no problem with checking for external flaws. But how do you know if there is a hidden marriage? After all, the most common defects are associated with the operation of the monitor matrix, for example, the presence of dead pixels or a slowed down speed of the matrix reaction, which you will not notice at first glance. For this purpose, special programs have been developed, as well as online services that are able to quickly and accurately test the monitor. One of the most popular programs for checking monitors is the utility. Its convenience is that it does not require installation, you just need to download the file with the program, and the interface is intuitive and simple. In the arsenal of the program there are several tests that need to be run sequentially.
As many may know, modern monitors often suffer from dead pixel problems... A dead pixel is a point on the screen that, for some reason, stopped changing its color in accordance with the image displayed on the screen. And it doesn't have to be a white or black pixel. It can be of any color.
Possible colors of dead pixels
Immediately after buying a TV, monitor, laptop or smartphone, it is recommended to check its display for dead pixels. In this article, you will learn how to quickly check for dead pixels online.
For online checks in our article there is a special site where you can change the filling of the screen with different colors to find those same non-working pixels.
And at the end of the article there will be a video, by running it in full screen, you can also easily online check the screen of your device for faulty pixels.
Monteon.ru - site for checking for dead pixels online
To start checking, go to the site:
Online checker for dead pixels
After that, the page of your browser will switch to the mode full screen where, by clicking the mouse, you can change the fill colors to find dead pixels of all types and colors.
Dead Pixel Test
To complete the check, press the "Esc" button on the keyboard and close the page of the site.
Video for online check for dead pixels
Play video in full screen mode.
The best way thank the author of the article - repost to your page
