black spot on tv lcd screen made in china

Responsible for performing installations and repairs (motors, starters, fuses, electrical power to machine etc.) for industrial equipment and machines in order to support the achievement of Nelson-Miller’s business goals and objectives:

• Perform highly diversified duties to install and maintain electrical apparatus on production machines and any other facility equipment (Screen Print, Punch Press, Steel Rule Die, Automated Machines, Turret, Laser Cutting Machines, etc.).

• Provide electrical emergency/unscheduled diagnostics, repairs of production equipment during production and performs scheduled electrical maintenance repairs of production equipment during machine service.

Having black spots on a TV screen can be very confusing and annoying for most TV owners. If you just spotted a black spot on your TV screen, you are probably worried that you’ll need to replace the entire set. But this should not be the case, especially since you spent a handsome figure getting the best TV available.

Perhaps the most common cause of black spots is dirt and debris that have accumulated on the surface of the TV screen over time. If ignored, it will lead to black spots.

Most TV owners would consider sending their TVs back to their manufacturer when they spot a black spot, like sending your best Vizio TV back to Vizio. Unfortunately, this can be time-consuming and expensive, especially if you’ve invested in one of the highest-rated OLED TVs and/or large models like the top 70-inch TV.

While most new TVs sold are smart TVs, you can still buy what is referred to now as “dumb TVs.” If you want a TV without apps and an internet connection, this is the TV for you. If that interests you, check out these top-rated dumb TVs. But keep in mind, unlike most new TVs, dumb TVs will usually be smaller, like a 24-inch size TV, for example. Regardless if the TV is smart or dumb, it can develop black spots, however. Fortunately, fixing a black spot is relatively easy. As a result, we have compiled a guide on how to fix a black spot on a TV screen.

STAT:Samsung was the most popular Smart TV brand in US households in 2020. Samsung had a 32% steady market share while Alcatel and Vizio had 14% and 13%, respectively (source)

Black spots can be a pain, especially if you just bought a wide color gamut TV and are looking to have enjoyable weekends. Regardless of where the black spot is located on your TV screen, it will stand out like a sore thumb. It’ll be the first thing you spot when your TV screen lights up. Black spots on your TV screen are caused by debris, dead pixels, or stuck pixels. This can be especially annoying if you invested in the best anti-glare TV and depend on good visuals for a good TV experience.Dirt or Debris: Perhaps the most common cause of black spots. Dirt and debris accumulate on the surface of the TV screen over time, and if ignored, will lead to black spots. If you have the best outdoor TV, be sure to keep up with maintenance and regularly clean it.

Manufacturer defect: Black spots will appear due to a violation of the assembly. They don’t appear immediately and often lead to damage to the display matrix. A warranty usually covers black spots caused by manufacturer defects.

Stuck Pixel: A stuck pixel is a pixel on the TV display that cannot change color. Display pixels are designed to change color depending on the image projected on display. When the color doesn’t change, it’s called a stuck pixel.

Dead pixel: It’s pretty different from a stuck pixel but often gets confused for one. While a stuck pixel will light up when the TV is turned on but does not change color, a dead pixel doesn’t light up at all. This is because all of their sub-pixels are turned off permanently, and since they don’t light up, they look like black spots on the TV screen. You can read our article on how to fix dead pixels on a TV to learn more about dead pixels.

Fixing black spots on your TV screen is quite simple.First, turn off your television and unplug it from the power source for a few hours. Sometimes, turning off the power on your TV will force the stuck pixel to become unstuck when you finally plug your TV back to the mains.

Next, verify that the black spot issues aren’t caused by any devices plugged into your TV, like a console or cable box. Remove all cables connecting your TV to components, and then plug them back in. Sometimes, loose connections cause distorted images that look like dead pixels.

If a black spot is still visible, contact your manufacturer or repair shop for repair service. Depending on the time and nature of the black spot, The TV manufacturer might cover the repair under warranty. You can also try the clouding LED TV fix, which solves the black spot problem common among new TVs but often disappears as time passes.

Regardless of where the black spot is located on your TV screen, it will stand out like a sore thumb. It’ll be the first thing you spot when your TV screen lights up.

While a stuck pixel will light up when the TV is turned on but does not change color, a dead pixel doesn’t light up at all. This is because all of their sub-pixels are turned off permanently, and since they don’t light up, they look like black spots on the TV screen.

Perhaps the most common cause of black spots is dirt and debris that have accumulated on the surface of the TV screen over time. If ignored, it will lead to black spots.

One of today’s modern technological wonders is the flat-panel liquid crystal display (LCD) screen, which is the key component we find inside televisions, computer monitors, smartphones, and an ever-proliferating range of gadgets that display information electronically.What most people don’t realize is how complex and sophisticated the manufacturing process is. The entire world’s supply is made within two time zones in East Asia. Unless, of course, the factory proposed by Foxconn for Wisconsin actually gets built.

Last week I had the opportunity to tour BOE Technology Group’s Gen 10.5 factory in Hefei, the capital of China’s Anhui Province.This was the third factory, or “fab” that Beijing-based BOE built in Hefei alone, and in terms of capability, it is now the most advanced in the world.BOE has a total of 12 fabs in Beijing, Chongqing, and several other major cities across China; this particular factory was named Fab 9.

Liquid crystal display (LCD) screens are manufactured by assembling a sandwich of two thin sheets of glass.On one of the sheets are transistor “cells” formed by first depositing a layer of indium tin oxide (ITO), an unusual metal alloy that you can actually see through.That’s how you can get electrical signals to the middle of a screen.Then you deposit a layer of silicon, followed by a process that builds millions of precisely shaped transistor parts.This patterning step is repeated to build up tiny little cells, one for each dot (known as a pixel) on the screen.Each step has to be precisely aligned to the previous one within a few microns.Remember, the average human hair is 40 microns in diameter.

On the other sheet of glass, you make an array of millions of red, green, and blue dots in a black matrix, called a color filter array (CFA).This is how you produce the colors when you shine light through it.Then you drop tiny amounts of liquid crystal material into the cells on the first sheet and glue the two sheets together.You have to align the two sheets so the colored dots sit right on top of the cells, and you can’t be off by more than a few microns in each direction anywhere on the sheet.The sandwich is next covered with special sheets of polarizing film, and the sheets are cut into individual “panels” – a term that is used to describe the subassembly that actually goes into a TV.

For the sake of efficiency, you would like to make as many panels on a sheet as possible, within the practical limitations of how big a sheet you can handle at a time.The first modern LCD Fabs built in the early 1990s made sheets the size of a single notebook computer screen, and the size grew over time. A Gen 5 sheet, from around 2003, is 1100 x 1300 mm, while a Gen 10.5 sheet is 2940 x 3370 mm (9.6 x 11 ft).The sheets of glass are only 0.5 - 0.7 mm thick or sometimes even thinner, so as you can imagine they are extremely fragile and can really only be handled by robots.The Hefei Gen 10.5 fab is designed to produce the panels for either eight 65 inch or six 75 inch TVs on a single mother glass.If you wanted to make 110 inch TVs, you could make two of them at a time.

The fab is enormous, 1.3 km from one end to the other, divided into three large buildings connected by bridges.LCD fabs are multi-story affairs.The main equipment floor is sandwiched between a ground floor that is filled with chemical pipelines, power distribution, and air handling equipment, and a third floor that also has a lot of air handling and other mechanical equipment.The main equipment floor has to provide a very stable environment with no vibrations, so an LCD fab typically uses far more structural steel in its construction than a typical skyscraper.I visited a Gen 5 fab in Taiwan in 2003, and the plant manager there told me they used three times as much structural steel as Taipei 101, which was the world’s tallest building from 2004- 2010.Since the equipment floor is usually one or two stories up, there are large loading docks on the outside of the building.When they bring the manufacturing equipment in, they load it onto a platform and hoist it with a crane on the outside of the building.That’s one way to recognize an LCD fab from the outside – loading docks on high floors that just open to the outdoors.

LCD fabs have to maintain strict standards of cleanliness inside.Any dust particles in the air could cause defects in the finished displays – tiny dark spots or uneven intensities on your screen.That means the air is passed through elaborate filtration systems and pushed downwards from the ceiling constantly.Workers have to wear special clean room protective clothing and scrub before entering to minimize dust particles or other contamination.People are the largest source of particles, from shedding dead skin cells, dust from cosmetic powders, or smoke particles exhaled from the lungs of workers who smoke.Clean rooms are rated by the number of particles per cubic meter of air.A class 100 cleanroom has less than 100 particles less than 0.3 microns in diameter per cubic meter of air, Class 10 has less than 10 particles, and so on. Fab 9 has hundeds of thousands of square meters of Class 100 cleanroom, and many critical areas like photolithography are Class 10.In comparison, the air in Harvard Square in Cambridge, MA is roughly Class 8,000,000, and probably gets substantially worse when an MBTA bus passes through.

Since most display manufacturing has to be done in a cleanroom and handling the glass requires such precision, the factory is heavily automated.As you watch the glass come in, it is placed into giant cassettes by robot handlers, and the cassettes are moved around throughout the factory.At each step, robots lift a piece of glass out of the cassette, and position it for the processing machines.Some of the machines, like the ones that deposit silicon or ITO, orient the glass vertically, and put them inside an enormous vacuum chamber where all the air is first pumped out before they can go to work.And then they somehow manage to deposit micrometer thin layers that are extremely uniform.It is a miracle that any of this stuff actually works.

It obviously costs a lot to equip and run such a fab.Including all of the specialized production tools, press reports say BOE spent RMB 46 billion (US$6.95 billion). Even though you don’t see a lot of people on the floor, it takes thousands of engineers to keep the place running.

The Hefei Gen 10.5 is one of the most sophisticated manufacturing plants in the world.On opening day for the fab, BOE shipped panels to Sony, Samsung Electronics, LG Electronics, Vizio, and Haier.So if you have a new 65 or 75-inch TV, there is some chance the LCD panel came from here.

@georgeydesign It"s a 24 inch TV. I"m a bit confused what is the LED panel? Is it like the whole screen of the TV or is it like a motherboard of some sorts. And would it be advisable to fix it or just buy a new one. I"m willing to learn how to fix it tho if that is the better way

Ever had your TV showing nothing but a black screen even if the audio was working? Unfortunately, that’s a common issue with low/middle-end LCD/LED TVs these days… Even more frustrating, this issue often comes from a rather tiny and cheap component that can be easily replaced. Most common issues are:

One of my relatives had this exact symptom happening all of a sudden. This problem on low-end TVs often occurs within the first couple years. As the repair costs for that kind of TV is pretty low, considering repairing it yourself might be a good idea!

The first step into repair is to find the root cause of the issue. As backlight failure is a very common issue, this is the first thing to test. To do so, the easiest way is to power on your screen, put a flashlight very close to it and check if you can see the image through. The image would be very dark, like turning the brightness of the screen very very low.

That implies disassembling the TV to access the backlight which is between the LCD screen in the front and the boards in the rear. In my case, with a Samsung F5000, I had to process as follows:

First we have to remove the back housing to reveal the boards (from left to right: main board, T-CON, power supply) and disconnect the LCD panel from the T-CON board.

Note: Older TVs have neon tubes for backlight, which is thicker and less exposed to this kind of failure. LED backlight is the most common thing these days, but do not mistake an LED TV with an OLED TV. The first one is a classic LCD panel with a LED backlight, whereas the second is an OLED panel that doesn’t need any backlight as it is integrated in each pixels (making the spare parts much more expensive by the way).

As we can see, the backlight system is made of 5 LED strips. First thing to do is look for burnt LEDs. Most LED backlight systems have strips set in series, meaning that if one of the them fails, all the system goes dark…

Using a multimeter, we can confirm that the strips are indeed set in series, so now we have to test each strip individually. Professionals use LED testers such as this one (about 40$ on amazon) but as I didn’t had one at the time, I decided to make one, McGyver style!