The iMAC screen into the gray problem, surely we all already know. In the past few years, Apple had claimed that this was China's air quality problem, but many students in the United States also said that their iMac was in heavy dust and hit the face. There must be a lot of classmates who entered the ash, but there are certainly more choices to endure in silence. I hope that I will criticize and educate the apple. If you do not know what the classmates can do in google photos. My iMac is this one
Two screens have been changed for free. Some friends are said to have changed four or five times... Did you work at a flour mill, so much ash... Fortunately, I chose AppleCare Red Apple. I would be kind enough to apply for a three-year warranty. Can apply for home replacement service. In the case of customer service in Beijing and Shanghai, it is basically difficult to apply for a door service. It is easier to transfer customer service to Singapore or Hong Kong Putonghua accent.
According to the maintenance master, if one needs to change, then one piece needs four or five thousand dollars. Due to the last replacement of the warranty period, I must think of ways to completely solve the problem of entering the ash, in order to avoid future problems. This is Apple's design flaw, although he does not admit it. According to the master of maintenance, since the Samsung screen was used early, there is no problem of entering the ash. However, in order to reduce costs later, Apple used a poorly sealed LG screen, and even ash is inevitable, as is Retina. The photo below is not my screen, but it is not serious for me.
To deal with this problem, the method I used was to install a T70 electrostatic filter with very low windage but high adsorption efficiency at the bottom of the screen.
HV static electret filter T70 made anti-fog and haze air-conditioning anti-PM2.5 screens negative pressure fresh air people air20 yuan Taobao direct links The first step is to prepare a double-sided tape with a width of five millimeters. The right-to-turn hardware department will sell it. My business was to send a roll when I bought the T70.
The second step is to cut the T70 filter cotton to a length of 0.5 to 65 cm. I am a bit of a snarl and a twist, I am sorry to show it to everyone.
In the third part, I first stuck the double-sided tape to the lower air intake, and then removed the layer on the top of the adhesive. 
Everything seems to be tight and the dimensions are perfectly matched, 
Then use a ballpoint pen to open the hole, but later found out that the pen is too thick, um... the paperclip opening will also tear the narrow tape on both sides. 
In this way, it went twice and it failed.
But I am not discouraged. I am not afraid of suffering. I am not afraid of difficulties. There is always a sunny day in life. I am not afraid of fatigue. I am not afraid of acid. My life is smiling. I am not afraid of mistakes. I am not afraid of it. , happy to sing the spirit of the song, tried again, and the previous two methods were iteratively upgraded :)
This time, I used a utility knife and opened it without opening the double-sided adhesive. The moment I picked up the blade, I realized that a little trick was that the blade slammed outwards.
In this way, it is not easy to tear the rubber strip on the desktop. This is the case after opening. It's been beautiful for a long time.
Look into the side of the hill into a pit
Remove coverage
This step of double-sided tape is the most difficult and most critical. After it is done, it can be worn on the iMac. It must be remembered that the more neat side of the T70 filter is affixed to the double-sided tape and the brow is exposed. Remember, hair should be exposed outside. 
After pasting, this is a Dingzhuang photo, we can see very beautiful, so completely avoid the screen into the gray, the future is to do regular replacement and re-post it.
Maybe this part will turn gray after two weeks. Who cares if I have unpredictable weather in heaven?
This article uses Kodak Voice-to-Speech input and then slightly collates.