A bright spot appeared on the Samsung TV screen

How to fix cloud spots on LCD TV screens

The defect appears in areas that appear grayer than black in dark scenes, along with uneven brightness in normal images. Sometimes corrected by a little pressure and adjusting the TV settings.

  • Clean, soft cloth.
  • Remote control.

Recent questions

Purchased in 2014. I have no complaints about the work. Three days ago, I noticed a spot of a strange configuration, it very much resembles an eye, an eyelid, a pupil. What is the reason?

Hello. It looks like the lens has come off the backlight LED. It is necessary to disassemble the matrix. Put in place.

It is necessary to disassemble the TV and re-glue the matrix backlight LED diffuser. It is better to do this in a service center.

the light diffuser bent over, you can fix it, but if you do it well, taking into account that the TV is 5 years old, you need to change all the LEDs, the repair amount is 3000r

Thanks for the answer. What happens if I don’t repair it? This stain does not bother me, but in the service center the TV can be broken and I will not prove anything to anyone.

Thank. And what are the consequences if I do not repair it ?

bright, spot, appeared, samsung, screen

In services, ask to pick up a reflector from the same model

The reflective lens has fallen off. Disassemble. stick back.

100% remote diagnostics. The lens is detached from the LED. Disassemble the matrix, glue it with superglue, assemble. Do everything with gloves, carefully. See link here

In addition to this “eye”, you can clearly see the darkening above it, apparently one of the backlight lines does not work. You can use it if you are not embarrassed by such an image. On the good, it requires replacing the LED backlight strip, revising the power supply. reducing the maximum current for the backlight and re-gluing the lens. diffuser.

A white spot appeared on the Samsung TV screen

Recent questions

Purchased in 2014. I have no complaints about the work. Three days ago, I noticed a spot of a strange configuration, it very much resembles an eye, an eyelid, a pupil. What is the reason?

Hello. It looks like the lens has come off the backlight LED. It is necessary to disassemble the matrix. Put in place.

It is necessary to disassemble the TV and re-glue the matrix backlight LED diffuser. It is better to do this in a service center.

the light diffuser bent over, you can fix it, but if you do it well, taking into account that the TV is 5 years old, you need to change all the LEDs, the repair amount is 3000r

Thanks for the answer. What happens if I don’t repair it? This stain does not bother me, but in the service center the TV can be broken and I will not prove anything to anyone.

Thank. And what are the consequences if I do not repair it ?

In services, ask to pick up a reflector from the same model

The reflective lens has fallen off. Disassemble. stick back.

100% remote diagnostics. The lens is detached from the LED. Disassemble the matrix, glue it with superglue, assemble. Do everything with gloves, carefully. See link here

In addition to this “eye”, you can clearly see the darkening above it, apparently one of the backlight lines does not work. You can use it if you are not embarrassed by such an image. On the good, it requires replacing the LED backlight strip, revising the power supply. reducing the maximum current for the backlight and re-gluing the lens. diffuser.

Unfortunately, the reality is that LCD screens (usually using a fluorescent backlight) can suffer from clouding. This is a phenomenon in which light “bleeds” into the visible area of ​​the screen, causing black unevenness.

Internal settings

Access the TV menu using the remote control. Navigate to the menu areas that adjust the backlight and brightness of the screen.

Lower the backlight to the minimum acceptable level. Often times, the backlight can be turned off (or very close to this state) without noticeable degradation in image quality. This will be an exercise in getting used to the reduced brightness versus cloudy visibility. Disable any automatic settings that adjust brightness based on room lighting. Often referred to as “iris” or “smart sensor”, they disable the amount of control needed to reduce the visibility of clouds in all viewing conditions.

Manual deletion

Turn off the TV. Take a clean, lint-free (preferably new) cloth and wipe gently from the center of the screen to the outside. Repeat until the visibility of the clouds decreases.

Loosen (but do not remove) the screws along the top rear of the TV. Often these screws are so tight as to cause the screen to warp slightly, causing visible uneven backlighting. Remember to fit the screws tight enough, however, to prevent the set from collapsing. Usually 1/4 stroke is sufficient

Rotate the LCD housing slightly until the screws are tightened. Turn on the technique to determine if the clouds have decreased. If not, re-tighten the screws on the back of the TV close to their previous strength. This way you can remove the bright spot on the TV screen.

A bright spot appeared on the Samsung TV screen

Almost every LCD TV today suffers in one way or another from this problem. uneven screen backlighting. Some areas of the screen, upon close examination, may appear brighter than others against a dark background. And, less often, darker spots are on a general light background. When viewing real video material, this flaw may become clearly noticeable in dark scenes.
So what is the reason for this phenomenon? And is there anything you can do?

All LCD TVs consist essentially of two parts: a backlight system and a liquid crystal panel, consisting of a matrix of cells that completely transmit or block light to varying degrees. Light sources are CCFL lamps or light emitting diodes (LEDs). Today’s LED TVs are exactly the same LCD TVs in design using LED sources instead of lamps for backlighting.

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In the simplest LCD TV, the backlight creates a constant stream of light, which is set by the adjustment of the regulator. On more expensive TVs, the backlight system can automatically adjust the flow of light in time and space, depending on the nature of the displayed material. In other words, during dark scenes, backlighting can reduce light levels, making the image appear darker than on a basic LCD TV.

A backlight system is never perfect, either due to manufacturing defects or design inefficiencies or other deficiencies. Because of them, individual areas of the screen begin to spontaneously transmit more light than adjacent ones.

Click on the picture to enlarge it

Disassembled layer by layer LCD TV. The layer on the far left is the clear screen covering. The next layer (where you see the image) is the liquid crystal matrix (LCD panel). The next layer (bright white plane) is the diffuser. In fact, it is a translucent “matte” plastic. Far right. backlight system in the frame of the TV.

Ideally, the diffusion layer should distribute the light evenly over the entire surface of the screen. But this is very difficult to achieve. To get a result close to optimal, you need to increase the number of lamps, use high-quality diffusing materials, improve the entire structure.

Therefore, cases with lighter stripes across the screen opposite the backlight lamps and darker ones in the gaps are likely. For displays with small screens in the backlighting system, only lamps located at the edges may be sufficient, which makes them structurally similar to models with a side LED backlighting system.

All LED TVs are the same LCD TVs

LED-backlit TVs, unfortunate enough to be called “LED TVs” in commercial reviews, use miniature and bright LEDs instead of CCFL lamps. Their poor placement can seriously affect the effectiveness of the screen backlight. In most LCD LED displays produced today, the LEDs are located at the edge (edge) of the LCD panel, which has a very negative effect on the efficiency of light distribution across the entire plane of the screen. Some models have two LED emitters, structurally mounted on the side of the LCD panel (top / bottom or sides), while some models have them on all four sides.

If you put a flashlight on a table, you will get an idea of ​​the problem that exists when the LEDs are located at the edge of the TV screen. The space immediately in front of the LEDs will be brighter, while the far space will be dimmer. In such HDTV designs, rather complex optical light guides are used, along which light propagates along the screen and is partially reflected in the direction of the LCD panel and through it to the viewer.

Each of these edge lighting methods has its own characteristics in terms of uneven illumination of the pixels of the liquid crystal panel. For example, on TVs with sources located on the side faces, a completely black screen may look like this:

When the backlights are placed above and below the panel, a completely dark screen with overexposed light areas will look like this:

If the LED backlight is placed around the entire perimeter of the screen and the backlight can be observed around the entire perimeter with a completely dark screen:

Potentially, there may be problems similar to the one noted below, but less visible and in smaller numbers:

The opposite pattern for screen non-uniformity will be for LED LCD TVs with a side lighting system in the case of a completely light screen. If the LEDs are placed around the entire perimeter of the screen, there will be a darker area in the center than around the edges. Here is a clear illustration of a similar case.

With top / bottom backlights, the darker bar may run horizontally across the center of the screen. And in the case of backlight sources along the sides of the screen. a dimmer streak may run vertically.

On some high-end LCD LED models, the backlight is located directly behind the LCD panel. This so-called Full LED system, it can provide a more uniform illumination of the entire surface of the screen, due to a more even distribution of individual sources. In addition, in this case, the so-called system can work quite effectively. local dimming, which allows you to independently adjust the brightness of individual, divided into zones, groups of backlight sources. As a result, it is possible to reduce the blackness of the dark parts of the image, relative to the light.

Plasma panels of the previous generation sometimes had similar problems with uneven backlighting of the screen. But these problems were reversed. The turbidity was observed not on a dark screen, but on a white field. Modern plasma models no longer have such disadvantages.

There is practically nothing that users themselves can do to eliminate uneven backlighting problems. Except for the advice on loosening the fastening of individual points of the rear panel, where the laminated panel structure can be unnecessarily squeezed in some places. But everyone follows such advice at their own peril and risk.!

Manufacturers, of course, spend a lot of money on improving existing and developing new systems with better LCD backlighting. However, there are several problems that make it difficult to create a perfect backlight system. The thinner the TV (and therefore the shorter the distance between the backlight and the LCD panel), the more difficult it is to achieve uniform light diffusion, given the limited space between the source and the LCD panel. Another problem is that better diffusion means more light loss, which is always undesirable.

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Finally, there is the issue of cost. The uniformity of the backlight is only one of the characteristics of the TV, and it is far from the first in the list, where the first positions are occupied by cost, luminous flux level, contrast, color, video processing. In any case, the TV is designed taking into account the final cost, which will limit certain quality characteristics.

Unevenness in brightness is difficult to notice on TV screens in sales areas and at home in a lighted room. Given this circumstance, the task for developers is simplified, allowing them to make compromises on the uniformity of the backlight in order to achieve increased brightness or other parameters, as well as reduce the cost of materials and the product as a whole.

Source: cnet.com
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Impact stains on the TV screen

We will consider in this article not only the spots associated with the reliability and quality of the matrix assembly. The spots from blows to the matrix in the hearts or accidentally leave for the next advice. to replace the matrix. Why? Because the fine structure of the matrix is ​​almost impossible to repair. It is easier and cheaper to make a new display than to restore an old one. Here are examples of spots that appear after hitting the matrix.

The spots from impact on the screen most often have clear boundaries and traces of cracks. Over time, blurry outlines may appear. these neighboring pixels begin to break from heating and internal stresses.

Plasma

White spots on the plasma panel indicate a malfunction of the units responsible for the construction of the image. In rare cases, it may be a matrix defect.

As a rule, you need to completely change the building blocks of the image.

Dust and other particles

White spots on the TV appear due to dust getting into the matrix layers. this is the result of a violation of the tightness of the layers. When the temperature fluctuates during the heating and cooling of the LCD screen, the air between the layers starts to move, sucking in dust from the outside. The photo shows which dust spots are formed after a few months of the appearance of a defect in the protection of layers around the perimeter.

Advice: dust is removed by blowing. This is done very carefully so as not to damage the matrix.

In addition to dust between the layers of the matrix, larger particles and even insects can get stuck (in exceptional cases, but this is definitely a factory defect). You can get rid of large dust and debris as follows: tap the screen with a soft cloth. So the dust particles gradually fall down, while weak traces may appear on the matrix, which immediately disappear.

In addition, dust particles can fall between the layers of the screen if you lightly tap on the edges of the TV or monitor.

Plasma

A plasma panel also has such shortcomings, only here the problem lies in the malfunction of the blocks that are responsible for the construction of the picture. In rare cases, this may be a defect in the matrix itself. To fix this problem, you will need to replace the image building block.

As soon as you notice problems with the image, and if the warranty period has not yet expired, then it is advisable to immediately send the product to a service center for repair or replacement. It should be noted that sometimes very small and not very conspicuous spots cannot always be regarded as a warranty case and will be refused repair.

CRT

On CRT TVs, white spots are usually strong highlights. This could be:

  • Vertical scan failure. The repair is quite simple (if spare parts are available).
  • Failure of the picture tube. Not suitable for repair.
TV type, causes and remedies

If the warranty period of the TV has not yet expired, you need to contact the service center as soon as possible and return the device under warranty. True, in some cases, light flares can be regarded as an out-of-warranty case.

Reasons for the appearance

Spots on a liquid crystal (LCD) monitor or TV most often appear during the operation of equipment. Not a single screen, even the most expensive company, is immune from such a malfunction. The main reason for the appearance of such errors is considered to be a factory defect.

But the spots are different. It so happens that when watching TV in some places of the screen (if there is a certain color in some area), you can see barely noticeable white highlights.

This situation can happen with any LCD, LED or plasma screen. But do not rush to sound the alarm, such an image may be a feature of this model, and not a defect.

In rare cases, such “spots” are a design feature. They can also include thin stripes along the edges of the screens a couple of tones lighter than the rest of the surface. Some people who are not tempted with a good image may not notice such shortcomings for years, and a picky user will immediately discover them. In other cases, such spots may appear during the operation of the TV, and each type of screen may have its own reasons for their appearance.

How to fix cloud spots on LCD TV screens

The defect appears in areas that appear grayer than black in dark scenes, along with uneven brightness in normal images. Sometimes corrected by a little pressure and adjusting the TV settings.

bright, spot, appeared, samsung, screen
  • Clean, soft cloth.
  • Remote control.
READ  Horizontal stripes appear on the monitor what to do

Internal settings

Access the TV menu using the remote control. Navigate to the menu areas that adjust the backlight and brightness of the screen.

Lower the backlight to the minimum acceptable level. Often times, the backlight can be turned off (or very close to this state) without noticeable degradation in image quality. This will be an exercise in getting used to the reduced brightness versus cloudy visibility. Disable any automatic settings that adjust brightness based on room lighting. Often referred to as “iris” or “smart sensor”, they disable the amount of control needed to reduce the visibility of clouds in all viewing conditions.

Spots in corners or around the perimeter

Dark spots on an LCD TV screen can be of different origins, and the cost, as well as the ability to repair, can be different. If dark oval or round stains appear around the perimeter or in the corners of the screen, then, most likely, part of the LED backlight of the matrix is ​​out of order. This defect is often found on TVs and monitors from Chinese manufacturers in the budget price segment. Such a breakdown can be easily eliminated by replacing burnt out diodes. In some cases, soldering the backlight contacts can help.

Dark spots from impact

In addition to factory defects and the influence of low-quality components, there are cases of darkening on the display due to mechanical damage. Such defects appear completely black with sharp edges and cracks. Vague edges may appear after a while. This is the result of overheating of neighboring pixels. In this case, there can be only one advice. replacing the matrix. Due to the thinness of the LCD panel, it has a very low maintainability, and its replacement is much easier, cheaper and faster. In addition, this method will help solve the problem with dark spots on the LCD TV screen at the root.

Darkening on a white background

Also, due to poor quality protection of the layers, dust can get into the matrix. When the panel is heated and cooled, it expands and contracts, respectively. She, like a pump, can suck in dust.

LCD/LED TV Repair Secrets. Bright Spots on the Screen

From the point of view of manufacturers, such “sores” can be explained by the desire to reduce the cost and simplify the design and components. And you can fix this with a simple purge. But it must be carried out as carefully as possible, since a dent or scratch, inadvertently left on the panel, cannot be removed.

Moisture stains

If a dark spot appears on the LCD TV screen, it may also be due to liquid getting between the matrix layers. Outwardly, they are almost identical with dust spots. Therefore, for self-diagnosis of a malfunction, you need to think about where and how moisture got into the TV or other display.

Theoretically, this problem can be solved by disassembling the matrix and rinsing the polarizer and diffuser. Of course, flushing should not be carried out with tap water, since after drying there will be stains from salts and deposits. For this, purified water or highly purified alcohol is more suitable.

But it is still better to entrust such procedures to qualified specialists, since during the disassembly or assembly of the matrix, irreparable harm to the device can be caused. If you decide to do this yourself, then it is necessary to disassemble and assemble in a clean room, preferably after wet cleaning, so that dust particles do not fly in the air. Gloves must also be worn to avoid leaving fingerprints on the matrix components.

Summing up

So what if dark spots on the LCD TV screen prevent you from enjoying the picture? Which of the cases are guaranteed, what can you solve on your own, and where you can’t do without going to the service? Let’s list all the options:

  • Black spots from mechanical damage. This case is not guaranteed, and it can be corrected only by replacing the matrix.
  • The same spots, but no impact marks. It may be possible to pass under warranty if there is no trace of mechanical impact on the case and screen.
  • Dust ingress. There is a chance that they will be accepted under warranty in the event of a marriage of the party. But it is also possible to rinse one or more layers. True, self-intervention automatically removes the warranty from the device.
  • Ingress of moisture. Initially not a warranty case, but the same rinsing as in case of dust ingress may help.
  • Failure of the backlight LEDs. The case is covered under warranty if there are no signs of tampering on the case. If the warranty has expired, you can replace the burned out diodes or the entire tape.
  • Rubbish between layers. If there are no signs of tampering, this is a warranty case. But you can fix it yourself by blowing the matrix.

I would like to note that this article was informational. If dark spots appear on the LCD TV screen, it is best to consult a qualified technician.

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