What should I do if the screen has bright spots or dark spots?

What should I do if the screen has bright spots or dark spots?

If the industrial control LCD screen has bright spots (pixels that are always on) or dark spots (pixels that are not luminous), you can try the following methods to solve the problem:

1. Check the screen status

Confirm the problem: First, confirm whether the bright spots or dark spots on the screen are persistent. You can observe the problem more clearly by displaying a solid color background (such as all black or all white).

Check the ambient light: Make sure there is no strong light source directly shining around the screen, because strong light may cause visual misjudgment.

2. Try software repair

Pixel repair tool: Some software tools (such as JScreenFix, Dead Pixel Tester, etc.) can help fix bright spots or dark spots. These tools try to "wake up" or "repair" the faulty pixels by quickly flashing the pixels on the screen.

How to use: Download and install the pixel repair tool and follow the software instructions. It is usually necessary to display a specific pattern or color on the screen and let the software run for a period of time (such as 10-30 minutes).

3. Physical repair method

Light pressure method: For bright spots, you can try to gently press the bright spot position with a soft object (such as an eraser) while quickly switching the screen display content. The principle of this method is to change the arrangement of liquid crystal molecules through physical pressure, which may help repair bright spots.

Temperature method: For dark spots, you can try to gently wipe the screen surface with a slightly damp lint-free cloth, and then let the screen run at normal temperature for a while. The principle of this method is to activate the faulty pixel points through slight temperature changes and humidity changes.

4. Hardware inspection

Check the connection cable: Make sure that the power cord and data cable of the screen are firmly connected and not loose or damaged. Loose connections may cause unstable signals, resulting in bright spots or dark spots.

Check the interface: Check whether the interface of the screen (such as HDMI, VGA, LVDS, etc.) has dust or foreign matter, and use a soft brush to gently clean it if necessary.

5. Professional repair

Contact the supplier: If the above method cannot solve the problem, it is recommended to contact the supplier or manufacturer of the screen. They may provide professional technical support or repair services.

Professional repair personnel: If the screen is still under warranty, you can contact the supplier for free repair. If the product is out of warranty, you might have to pay for repairs.

Shenzhen Zhiyan Optronics Co., Ltd. (zylcdshop.com) is a trusted supplier based in China, specializing in high-performance LCD screens. Backed by over 18 years of industry expertise, we deliver reliable, cost-effective display solutions and responsive support—customized to fit your specific business needs.