15 Tips to Identify the Quality of LED Display

Identify LED Screen Quality

Table of Contents

The quality of a device matters a lot. In reality, we exchange our money for the quality of a machine. It is a fact that what you buy regularly, you know its quality. You know how to identify between the best and the worst of it. But what if you are purchasing a device for the first time? How can you specify if it is good or not?

I am sure you will be looking for good quality LED display. But how can you identify it if you don’t know its essential features? Today, we will discuss some critical points regarding the quality of a display screen. Then, after learning things, you can easily select a quality display screen.

  • Brightness
  • Viewing distance and viewing angle
  • Flatness
  • White balance
  • Pixel pitch
  • Color restoration
  • Raw materials
  • Color block
  • Mosaic or dead spot
  • Wavelength
  • Power consumption per square meter
  • Refresh rate
  • Contrast ratio
  • Color temperature
  • Indoor small spacing display screens


Brightness plays a vital role in the image quality of the display screen. If the brightness level is not correct, it can affect the display. As a result, the audience may not be able to enjoy the best visuals. Thus, you need to check the brightness of the LED display first.

There are different brightness levels for indoor and outdoor LED displays. For indoor screens, the brightness can be around 500-1500 nits. The brightness levels for outdoor screens can be about 4000-7000 nit or more. Nits are the unit for the measurement of the brightness of display screens. LED chip decides the brightness of the screen.

So, you would have to check the brightness of the screen. Make sure to match the brightness with what you need at the installation site.

Identify LED Screen Quality

Viewing distance and viewing angle:

In simple words, viewing distance is the minimum distance you can view the content. So, first, you must see what viewing distance you need for your screen. Then, see if the screen has it or not.

The viewing angle is also very crucial. It is the maximum angle from both sides where you can see the content. The LED display should have a viewing angle of 120° at least. It decides the number of audiences that can see the content.


It is another crucial point to notice for the display screens. It can affect the display if your screen body is concave or convex. It can result in blind spots from different viewing angles. It should be within 1mm. Otherwise, the image can become distorted.

The gap between the cabinets or modules should also be within 1mm. This flatness of the LED video wall mainly depends on the manufacturing process.

Identify LED Screen Quality

White balance:

You have to pay proper attention to this point also. It can be a good indicator of the quality of the screen. When the ratio of RGB is 3:6:1, it can display pure white only. Any change in this ratio can result in a difference in the white balance.

The physical parameters and control system determine the white balance of the screen. Therefore, you can check if the white balance is correct or not. For example, it can be blue or yellowish-green stained.

Pixel pitch:

It is essential to select the correct pixel pitch. Distance from the screen is the only factor that determines image quality. First, calculate the pixels you want on your screen. Then, select the screen. Don’t underestimate the importance of these features. You should thoroughly examine the pixel pitch before buying the LED display.

Color restoration:

Color consistency is essential for the display screen. To achieve it, we need to make the color restoration. The display screen should have a suitable color restoration property. It has a relation with the display and realistic image quality.

Raw materials:

You should check the quality of materials used to build the LED display. Of course, these materials should be of the highest quality. But, one cannot be adequately sure about the materials. It is not easy to know the quality of materials without experts.

LED lamp is one of the most critical raw materials to consider. Nationstar brand offers reliable and stable quality LED lamps. It would help if you asked the supplier about this. Which brand of the lamp are they using? You can even ask the supplier to send proof from Nationstar that they are using its LED lamp. In this regard, Dreamway Technology provides you with this opportunity. You can send the sample to us. We can help you check whether it is from the Nationstar brand.

In this regard, you should select a reliable and trustworthy LED company. Furthermore, it would help if you bought the display from a manufacturer that you can trust. The supplier should also give you some guarantee of the product.

Identify LED Screen Quality

Color block:

It is due to the color difference between the modules. It occurs due to the low grayscale level. And if the LED lamps are from different batches, their wavelength and brightness can vary. As a result, the color may be different. It can also cause a color block.

Make sure there are no color blocks on the display screen.

Mosaic or dead spot:

Mosaic is the bright or dark small squares on the display screen. It happens due to the following reasons:

  • During LED encapsulation, there is a need to classify each batch of LED lamps. If this classification is not well, it can cause brightness inconsistency.
  • If there are different SMD machines during production, it may cause a problem. The quantity of tin can be more or less. And it can result in the issue of displacement.

Dead spots are bright or dark single points on the display screen. Dead spots or dead lamps are due to:

  • The LED lamps get damp.
  • During the assembly, there is cold soldering. It can also cause a dead pixel.

Again, make sure there are no such spots on the display screen.

Identify LED Screen Quality


It is pretty vital to estimate the wavelength. Wavelength decides whether the color is consistent and pure. Unfortunately, it can be rather tricky for you to confirm the wavelength accuracy. It is because you might not have the professional equipment to do so.

But let me tell you there is no need for any equipment. You can check it by a simple procedure.

First, make the whole screen white. There should be no mixing of any color that should be pure white. If there is any mixing of colors like reddish or bluish, it will show that there is something wrong.

The color deviation proves that it has problems with its materials. So, we should not prefer such screens. These minor problems will become more significant with time.

The second step you must follow is to make the screen whole red, green, and blue. Then we must notice the standard blue, green and red under the central wavelength. A darker or lighter color will usually estimate deviation in wavelength. The inconsistent color indicates that the wavelength is too large.

Take an example of Nationstar SMD1515 LED lamps. The wavelength is 619-624 nm. Now, this wavelength should remain within 5 nm. For green LED, the wavelength is 528-532 nm. It should stay within 4 nm. And the same is the case with blue LED. The wavelength for this is 470-474 nm. It should also remain within 4 nm. By controlling these within the ranges, we will get a suitable wavelength.

Identify LED Screen Quality

Power consumption per square meter:

It is the power generated by the LED screen with an area of one square meter. We measure it in watts. For electricity consumption, we always use a watt per hour as a unit.

For example, say the power consumption of an outdoor screen is 800 watts per square meter. Then it means its electrical consumption is 800 watts per hour for one square meter of screen.

We usually consider two indicators of power consumption of LED screens. These are:

  • Maximum power consumption
  • Working consumption

Working consumption refers to the power it consumes for normal working. Maximum power consumption refers to the power it consumes for maximum output. For example, it needs the power to display content at full brightness.

You must be thinking about why we are discussing this. Well, it allows you to select the best LED. Then, you can easily calculate its maximum power consumption. First, you should count the number of power supplies inside the cabinet. Then, multiply it by the full power of each. Now you can calculate the maximum power consumption per square meter. For instance, three power supplies are in a cabinet, each 300W. Then you can see this cabinet is less than 900W.

Identify LED Screen Quality

Refresh rate:

For good quality LED, screen refresh rate is an important feature. It refers to the number of times the screen shows a new image per second. Its unit is Hertz.

Low refresh rates will badly affect the image quality. It will make the image unsteady for people’s eyes. Moreover, scanning lines appear in cameras when people shoot on the screen.

The refresh rates for a human eye should be above 300 Hz. Above 300 Hz, there will be no fluctuating impressions on the eye. For our rental LED display, the refresh rate is above 3,000 Hz. At this frequency, there will be no scanning lines.

You want to know how we can check the high refresh rate. We can use digital cameras for this purpose. The camera will take sharp pictures if the screen has a high refresh rate. There will be no snow spots or scanning lines.

Identify LED Screen Quality

Contrast ratio:

For a LED screen, contrast is crucial for good quality visual effect. It refers to the calculation of different brightness levels. It is a ratio between the brightest white and darkest black in an image’s light and dark areas.

The larger the difference, the greater the contrast. Similarly, the smaller the difference, the lower the contrast.

For a better visual experience, we need high contrast. High contrast will make the image clear and spectacular. It will also make the image brighter. In comparison, low contrast will cause the image to be grey. Thus, it will compromise the image quality.

So, you must have to check the contrast of the display. This product will bring no benefit if the visual experience is not good.

Color temperature:

The color of the images on the display screen should be consistent with the image source. When it is inconsistent, it means there is severe image distortion. It is generally related to the color temperature of the white balance of the LED screen.

The range of color temperature of the white balance is between 6500K to 8000K. It will be appropriate for people to look at the display screen within this range. This range applies to the case when people look at it with their naked eyes.

Indoor small pitch LED display:

For the indoor small pitch LED display, two factors are of great concern these are:

  • Low brightness
  • High grey level

Identify LED Screen Quality

Low brightness and high gray level mean there won’t be a gray level loss. It means the loss will be unobservable by the human eye when the brightness range is between 300-600 nits.

These two factors are crucial in determining the quality of small pitch LED display. Although we always prefer high brightness for outdoor screens to check their quality. But it is quite the reverse in this case.

For the small pitch LED display, we will prefer low brightness. In short, the quality they pursue is no longer high brightness but low brightness.

We tend to reduce the brightness level. The decrease in brightness does not affect the image quality. There is also no compromise on the gray level of the screen.

I can clarify by saying that we all need low brightness and high grey level. These two factors make these competitive screens products. For sure, these are in line with user requirements.

In the case of these screens, high brightness could be harmful to the human eye. If people look at these screens with high luminance for a long time, their eyes may get tearful. It can be even more severe and lead to sore and blurred visions. Thus, the too high LED screen brightness can cause visual fatigue to the users indoors. There will also be the chance of irreparable eye damage in severe cases.

So, we have to maintain it in a range between 300-600 nits. It will be desirable to the human eye.

Sunny Wong
Sunny Wong

Hello. I am Sunny Wong, the author of this post.

I entered the LED screen industry in 2008 and have always been in this field.

The purpose of this article is to share with you the knowledge related to LED screens from a Chinese supplier’s perspective.

If you want to distribute or explore your local LED screen market, please ask me any questions.

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