Top 3 The Most Common Problems With Liquid Crystal Display

Top-3-The-Most-Common-Problems-With-Liquid-Crystal-Display

Outlines:

  1. What are the most common problems with LCDs displays?
  2. Fixing stuck pixels
  3. Fixing LCD residual images
  4. Broken pixels
  5. What Are The Five Key Lcd Display Challenges You Can Face?
  6. What To Pay Attention To When Using The Module?
  7. Final Words

1. What Are The Three Most Common Problems With LCDs Displays?

LCDs can suffer from the following three problems that can be irritating to have on your screen:

  • Stuck pixels, 
  • Broken pixels, 
  • Residual image

Here are some strategies to fix these problems if they occur.

2. Stuck Pixels

LCDs are composed of a fixed grid of tricolor pixels that change transparency based on the display’s controller’s range of voltage levels. The pixel is opaque without a voltage and blocks the screen’s backlight from transferring through it. And when a full voltage is applied, the pixel allows the total transmittance of the backlight. When this is done over the entire pixel grid in patterns, you see those patterns on the screen.

At an elementary level, the way pixels work is a voltage change alters the pixel to allow more or less light through it. No light is let through when there is no voltage. When the voltage is at its maximum level, a hundred percent of the light can pass through it. By supplying intermediate voltages, the computer adjusts the pixel’s transmittance levels for its three color components to show various combined colors and intensities.

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Fixing Stuck Pixels

One of the more common problems with LCDs is the potential for stuck pixels, where the pixel does not receive a voltage and remains black. Or it does not respond to voltage changes and stays at a set luminance level. 

When stuck pixels occur, you can try several things to fix the problem. One is to apply a small amount of pressure to the pixel when turning the display on or off, which can help stimulate the electronic devices to work correctly.

The alternative to using pressure is to exercise the pixel’s electronics by using a program that displays quick-changing patterns on the screen and rapidly switches the pixels on and off. Remember that fixing stuck or dead pixels can be a hit-or-miss process, so do not be surprised if a broken pixel does not come back to life.

fixing-stuck-pixels-problem-with-LCDs-displays

3. LCD Residual Images

Another problem called “transient persistence” is also affected by LCDs, reminiscent of CRT burn-in. Classic burn-in would happen due to the phosphor coating on the screen, and it would get depleted by the persistent bombardment of electrons from the CRT. These things result in the inability of those sections of the display to convert the electron beam to visible light. 

This meant that if you kept a specific pattern showing on the screen, it could become a permanent residual image on display over time that would show even when the display was off. That’s why screensavers were developed to keep the wear on the screen’s phosphor coating as even as possible.

The physical burn-in of displays is no longer an issue now that LCDs have taken over. Still, while transient image persistence is not a physical burn of the device, it alters the pixel response to voltage changes, preventing pixels from getting as bright as others on the screen.

LCD image persistence generally happens after you have displayed a pattern of intense colors on the screen. 

LCD-residual-images-problem-with-LCDs-displays

Fixing LCD Residual Images

LCD persistence can sometimes set in after only a few hours of displaying the image, instead of the weeks or even months it can take for the burn to set in on a CRT display. Additionally, image persistence is reverse-able.

What happens with LCDs is the affected pixels have lost their ability to respond to the full range of voltages that the display gives them, resulting in a limited range of colors that can be output. This can happen if the pixel cannot reach the level of luminance desired when given a specific voltage or acts as a capacitor and retains a residual charge. Either way, the pixel cannot get its full range of possible intensities.

Image persistence will benefit from a lengthy stretching of the pixel’s range, you might place a pure white window over the affected area for a few hours or even a few days if necessary, and this will force those pixels to be fully on and over time their intensities may increase to be the same as the surrounding pixels.

Likewise, try turning off the pixels fully by shutting down the display for an extended period or placing a pure black texture over the affected area (see the LCD Repair tool listed above for this option as well). This will turn the pixels entirely off and allow residual voltage in them to drain slowly over time.

Fixing-LCD-residual-images-problem-with-LCDs-displays

4. Broken Pixels

The system’s backlight can also suffer some common issues: 

  • The backlight randomly blinking off, 
  • Not turning on, 
  • Only illuminating part of the screen.

When the display entirely cuts out and does not show any light, one possibility could be that your computer is not correctly communicating with the display, or the display’s controllers or power supply is not working correctly. If this happens, try connecting the display to another system to avoid this issue.

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Fixing Broken Pixels

If only the backlight is broken down, then the LCD panel itself should be working or rendering the text and images of your computer’s output is just fine. Use a bright flashlight to test for this and shine it on your screen at an angle in an area where you expect images and text. 

If shining an alternative light source on display causes graphical content to show up, then either the backlight or some component involved in controlling it has failed. It will likely need to be replaced, especially if you cannot rectify the problem by restarting the system, resetting PRAM and SMC, or toggling different hardware and software settings on your system.

fixing-broken-pixels-problem-with-LCDs-displays

5. Five Key LCD Display Challenges You Can Face

There are five most common problems with LCDs you can experience with them. Five simple words that can equate to significant LCD challenges for you are listed here. 

  • Obsolescence
  • Delivery
  • Quality
  • Performance
  • Cost

6. What To Pay Attention To When Using The Module?

We will encounter various problems when we produce and use LCD modules, among which the essential points are following: 

  1. Guarantee that the liquid crystal is not damaged by knocking; 
  2. Ensure that there is no dark area in the light-emitting area of the backlight; 
  3. Make sure that the capacitor resistance and IC on the PCB board are fused to the corresponding position stably. 

7. Conclusion

To avoid all the above-discussed problems, consider that choosing the right supplier based on your volume and quality needs is very important for you. Then implementing the optimal LCD solution with the optimal features and performance is essential.  

We strongly encourage our clients to reach out to us if they are developing a new product that requires a display or holds one or more of these problems.

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