Why is the phone screen black and not the other color when it is turned off?

The reason why the display is black is because black absorbs all the color light, so you can only see the light emitted by the screen clearly, and will not reflect to the human eye because there are other lights around the outside world that are the same color as the original color of the screen, so that we can't see the screen clearly. Here's an example. If the screen is made blue and the screen happens to be red, both the blue and red colors of the sunlight will reflect off the human eye, making it impossible for the user to better judge the color.

There is also a historical legacy, the history of which can be traced back to the moment when television technology was born.

Before color television, there were only black and white televisions, and to put it more simply, there were only gray with different shades. In addition to being able to adjust the brightness,Black and white TV only has"Contrast"This dimension,To determine whether the screen is a thicker or lighter gray。 In contrast, color TVs also have "hue" and "saturation" to determine what we usually call a color "right or not".

When only one color is gray, and the picture is very unclear, it is difficult to see what is being played on TV, and improving the chiaroscuro is the first priority. It doesn't matter what color it is red, yellow, green, or blue at the beginning, it is all different shades of gray after it is photographed. Therefore, white on black or black on white is the only option to be able to see clearly.

Some reflective LCD is gray, just like a calculator or the previous GBA, after the power off, the light transmittance of the liquid crystal pixels returns to the power-off average, and there is a reflector behind this kind of screen, which reflects the ambient light, and it is gray after the panel is semi-transparent.

Other screens, such as the LCD screen of the current mobile phone, belong to the transmissive type, one of them has no backlight after the power is off, and the second is that the light transmittance of this kind of screen is low after the power is off, so it looks black.

OLED、Plasma、CRT TVs all rely on pixels to emit light,These screens are naturally black when they are not powered on,They basically do not reflect ambient light,Otherwise, the screen can't go down at all when it is black,Unless you pull the curtains and turn off the lights。

Because black does not affect the power consumption of the phone, and the rest is black.

Because black is very recognizable.

Because black is the original color, black does not consume electricity.

Because black is more subtle, it is easier to distinguish.

It may be that black is the most power-saving, so it is set like that.

Because a black screen doesn't let light through.

Because other colors are power-hungry.

Because the other colors are too bells and whistles.

The black is not as vibrant, and it also saves power.

Set it to black to save your phone's battery.

It may be caused by the night mode being set.

Solution: Turn off your phone's night mode.

1. Take Huawei nova5ipro mobile phone as an example, the operating system is Android, open the state and the phone, and then swipe from the top to enter the notification center.

2. In the notification center, click the dark mode icon to turn off the mode.

3. In addition, you can click on the settings icon of the mobile phone to enter.

4. In Settings, click on the Display & Brightness option.

5. After entering, click the switch behind the dark mode.

6. After clicking to turn it off, you can also turn off dark mode.

It may be caused by the night mode being set.

Solution: Turn off the night mode of the hand lead delay machine.

1. Take the Huawei nova 5i Pro mobile phone as an example, the operating system is Android, turn on the phone, and then swipe down from the top to enter the notification center.

2. In the notification center, click the dark mode icon to turn off the mode.

3. In addition, you can also click the settings icon of the phone to enter.

4. In the settings, click on the options for Display and Brightness of Wuzhou.

5. After entering, click the Huai Ant Li switch behind the dark mode.

6. After clicking to turn it off, you can also turn off dark mode.

It may be caused by the night mode being set.

Solution: Turn off your phone's night mode.

1. Take Huawei nova5ipro mobile phone as an example, the operating system is Android, turn on the phone, and then slide down from the top of the department to enter the notification center.

2. In the notification center, click the dark model core icon to turn off the mode.

3. In addition, you can also click the settings icon of the phone to enter.

4. In Settings, click on the Display & Brightness option.

5. After entering, take the pin carefully, and click the switch behind the dark mode.

6. After clicking to turn it off, you can also turn off dark mode.

Is it set to the banquet cavity into a power-saving mode?,The screen is very dark under the power-saving mode Li Xiangying,You can see the screen text in a dark place.,And then hurry up to the settings to turn off the power-saving mode.。

After the phone is turned off normally, the screen is black.

Another situation may be that the brightness of the phone is too low, which can be adjusted.

Try adjusting the brightness of your phone.

If you use a vivo phone, the black screen is displayed

1. Force restart your phone.

Try force restarting your phone to see if it is back to work, and check if the power and volume buttons are stuck in the case.

Force Restart Method:

Models released before September 2017 (models before x20): Press and hold"Power button"More than 12 seconds.

Models released after September 2017 and new models released later (x20 and later): Press and hold at the same time"Power button"+"Volume down key"More than 10 seconds.

NEX 3 NEX 3S: Press and hold the top round button for more than 10 seconds.

2. Upgrade the system version.

Please upgrade your phone to the latest version to view.

3. Reset all settings.

Go to Settings - System Administration - Backup & Reset - Restore all settings and follow the on-screen prompts.

Note: Restoring all settings will not delete any data or files, only all settings of the phone will be restored, some third-party application accounts need to be re-logged in, please confirm that it does not affect the use of the software before operating.

4. Service center testing.

If the above methods fail to solve the problem, please back up your mobile phone data in advance, and bring your mobile phone and purchase voucher to the vivo customer service center for testing. Customer service center address: Enter the vivo official website vivo**app--my-service outlets or vivo official website web version--bottom of the bottom--service support--service network inquiry--select the province and city to query the customer service center address.

It is recommended to contact ** in advance before going to avoid empty running, plan the itinerary reasonably, and travel safely.

When the screen of the mobile phone is exposed to high temperatures, such as when it is burned with a lighter, it will turn black locally. This is because the screen substrate is heated, causing the display components to stop working. When you stop burning, it will come back after a while.

If your phone shows a black screen, there are many reasons, system issues, software conflicts. If the screen is damaged, it will be illuminated as a black screen, and it is generally recommended to perform the following steps to troubleshoot and deal with it:

1. Press and hold the power button for more than 10 seconds to try to turn the device on and off again. If the fault persists, it is recommended to send the phone to the nearest service center for testing.

2. If you can operate the phone after restarting, uninstall the third-party plug-in program that operated before the black screen.

3. Back up your phone data (**book, SMS, multi** files, etc.), and restore factory settings.

If the problem persists, please bring the purchase invoice, repair card and machine to the service center, and the engineer will check the machine and deal with it.

If your phone has a black screen, it is recommended that you try it:

1.Press and hold the power button (some machines need to press and hold the power button and the volume down button at the same time for more than 7 seconds) to restart the machine.

2.Connect the charger to see if there is a charging display;

If it is invalid, please bring the purchase invoice, repair card and machine to the Samsung service center, and a professional after-sales engineer will help you test it.