Looks like AMOLED without interconnection (PWM) (updated periodically) - slavyan74 - LiveJournal. Select a monitor without PWM What do you start with a PWM monitor?

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Rare-crystalline (LCD-) monitors are used in different minds, so it is necessary to use displays that allow you to change the brightness and performance characteristics both in light and in the dark. Then the user can adjust the screen to a comfortable level of brightness, keeping in mind the work and dark lighting.

In the technical characteristics of the display, manufacturers should specify its maximum brightness, but it is important to take into account the lowest brightness values ​​on which screen you are using, even though you are unlikely to want to display it at maximum brightness. If the specifications often include values ​​up to 500 cd/m², you will need to set the screen to a brightness that is as comfortable as possible for your eyes.

We would like to remind you that from our reviews on the website tftcentral.co.uk we are checking a new range of brightness control and other brightness values. When calibrated, we can also set the screen brightness to 120 cd/m², which is recommended for a PK monitor for extreme brightness reasons. This helps to eliminate the idea of ​​those who establish such a fervor of brightness that you, having done everything, want to vikorize him every day.

Yak at the PIDSVICHUVANNY on Luminzent Lamps (CCFL), so I at the Svitlodіdo (LED-) pIDSVICHUVANI, ZMINA YASRAROSTISHY DISPLYASHYALYS IN AND EVERYTHING OF ZAMMENTS OF NOTSIONAL SVITLOVIDACHICHICHICHICHICHANNY. Nowadays, to weaken the brightness of the backlight, pulse width modulation (PWM, Pulse Width Modulation, PWM) is most often used, which is already widely used in the displays of desktop computers and laptops. Tim no less, this method does not eliminate any problems, but with the emergence of displays with high levels of brightness and wider LED backlighting, the side effects of PWM have become less noticeable, even earlier, And in some cases, SHIM can be the cause of blindness in people who are sensitive to it.

The purpose of these articles is not to instill anxiety in you, but to reveal how we work, why it is wrong, and how to check the display to see the effects more clearly.

What is PWM?

Pulse width modulation (PWM) is one of the methods of reducing the brightness that is detected in displays, which results in rapid cycling and dimming of the backlight. Such periodic supply of pulses is generated at a constant frequency, and the supply of waste to the part of the skin cycle, during which stimulation is turned on, until the final waste of the cycle is called the replenishment factor (magnitude ina, zvorotna shparuvatosti). By changing the spacing, you can change the ignition light supply. On a basic level, this mechanism ensures that the mixing of the wet and dry preheating stations is expected to be completed quickly, and the koristuvach does not mark the measure, as long as it is due to between the threshold there are angry moments (report about the price below).

Below you can view graphs of light output over several cycles from the “ideal” PWM values. The maximum light output in this application is 100 cd/m², and the brightness that is absorbed for the filling coefficients is 90%, 50% and 10% - 90, 50 and 10 cd/m² types. It's okay. The relationship between the minimum and maximum brightness levels over the course of one cycle is called modulation depth and at this point becomes 100%. Make sure that as the cycle goes on, the brightness of the illumination is maximum at the pointed butt.

Coef. pollution 90% Coef. pollution 50% Coef. pollution 10%

Analog (without PWM) graphs that indicate the levels of brightness that are received are presented below. Here the modulation is daily.

Consistent brightness 90% Constant brightness 50% Constant brightness 10%

Why bother with PWM?

The main reasons for the use of PWM are the ease of its implementation, for which type of lighting requires the device to be switched on and off frequently, as well as the wide range of possible brightness values ​​that can be ensured by I will help you.

You can change the brightness of the CCFL-switch by reducing the flow that flows through the lamp, or approximately twice as much as possible to the flow and voltage. This is the only simple way to achieve a wide range of brightness control. The CCFL lamp is controlled by an inverter, which turns on and flashes at a frequency of tens of kilohertz, which lies beyond the threshold noticeable to humans. However, PWM operates at a lower frequency, around 175 Hz, which can cause significant image defects.

The brightness of the LED backlight can be adjusted in a wide range of ways by changing the flow that passes through them, although as a result the color temperature will still change. This analog approach to changing the brightness of the light-emitting diodes also avoids the fact that additional lances are responsible for absorbing the heat seen by the light-emitting diodes. When the power is turned on, the LEDs heat up, which changes their supports and increases the flow that flows through them. This can cause the struma in bright LEDs to grow rapidly and cause them to go out of order. With a constant PWM stream, it is possible to smoothly remove the stream at a constant level throughout the operating cycle, as a result of which the color temperature is always the same and the revantation of the stream does not occur.

Side effects of PWM

Regardless of the usefulness of PWM for video processors due to certain reasons, if not taken care of they can also lead to unacceptable visual effects. To understand what we need, we need to look at the depth of these displays. Below is a video recording of CCFL-suppression, performed 40 times, so the effect can be more pronounced. Graphs of changes in brightness of RGB components over one cycle are shown directly below it. This particular display is adjusted to its minimum brightness, when the light is brighter.

As can be seen from the video and related graphs, over the course of one cycle, the brightness changes approximately 4 times. What’s important is that the color of illumination also significantly changes with the duration of the skin cycle. More than anything, this is due to the fact that the luminophores in the CCFL are subject to evaporation, which is being cut off, and in which case we can create a prototype that luminophores are used when purging the blue light, possibly including Tissya and vymikatsya more, lower for other colors . The drying of the phosphors also means that the light will continue to fade for a few milliseconds after the light is turned on at the end of the work cycle and will provide more power The same level of light (less modulation), less or less. Please note that the averaging of the hourly color becomes unchanged.

The thickness of the LED backlight is much smaller, the lower the thickness of the CCFL backlight at the same sparsity, the fragments of the LED will then roll in and out onto the surface. This way it will not continue to light after turning off the life. This means that where the CCFL backlight showed a smooth fluctuation of brightness, the light-LED version shows sharper transitions between high and low levels. Just recently, the topic of PWM began to be raised on the Internet, and in view of aphids, more and more displays with light-emitting diodes based on white light appeared. Iodine (W-LED). As you can set the volume lower, there is no need to change the illumination color during the work cycle.

A particularly noticeable effect occurs when the koristuvach’s eyes collapse. With gradual lightening without shadowing (for example, with sunny light), the image smoothly blurs, and thus the color is captured. However, when paired with a light source that vikorista PWM, people can immediately end up with a number of separate redundant images on the screen, which can lead to a decrease in the ease of reading and fixing a glance at something. ktah. From previous analysis of CCFL-suppression we know that color may be affected when the output image is black and white. Below is an example of how the text might look in the world of a horizontal eye with different types of illumination.

Output image Without PWM PWM with CCFL-switched PWM with LED-switched

It is important to remember that this includes the lights, and the display shows static images. It is often said that people cannot capture more than 24 frames per second (fps), which is not true and in fact does not indicate the approximate frame rate required to cope with non-stop crashing. In fact, with Russian eyes (for example, when reading), you can really get the effects measured at several hundred hertz. For some people, the quality of the markings significantly increases and tends to lie down due to the expansion of the crust before the display, since the peripheral view is the most sensitive.

How often does the backlight switch on and off when the PWM switches off? Obviously, this should be based on the type of lighting that is being victorious. The illumination based on fluorescent lamps often switches at a frequency of 175 Hz, or 175 times per second. The frequency of the light-emitting diode illumination, according to various data, increases from 90 Hz to 420 Hz, and at lower frequencies the frequency is much lower. It may be that the frequency is too high to be noticeable, but do not forget that 175 Hz is not much more common, at least 100-120 Hz, typical for lighting lamps connected directly to the electrical cutoff.

In fact, the 100-120 Hz frequency of fluorescent lamps has been associated with symptoms such as eye strain and headaches in humans. In addition, high-frequency stabilizing lancets were installed to ensure uninterrupted light output. Vikoristannaya PWM at low frequencies leads to new changes in the shortening of the stabilizing lances in the subswitch, the fragments of the dzherelo mayzhe uninterrupted light in which phase again turns into a slow light. Please be aware that low-acid or defective lighting stabilizers based on fluorescent lamps may produce noticeable noise. Most often, this occurs when the PWM frequency is low, the electronic fragments are currently moving to the right of the additional frequency, due to which the energy supply changes.

It is also important to understand the difference between multiple displays based on electron tubes (CRT, CRT) and TFT displays with CCFL and LED backlights. At that time, as the EPT can move at a low frequency of 60 Hz, even if the dark dark is lightened at the same time, fragments of the electronic circuit collapse downwards. When using TFT displays with CCFL and LED backlights, the entire surface of the screen lights up at the same time, which means more light is produced in a short hour. In some situations, it may be unsuitable to use a thinner ELT, especially with high steaminess.

For some people, the presence of shadows in illuminated displays may be important and unnoticeable, but for others it is even noticeable due to natural differences in the human eye. With the increasing use of high-brightness LEDs, for brightness control, high-brightness PWM has to be increasingly used for brightness control, which makes the problem of dimness more pressing. Doctors who spend a lot of time watching their monitors every day, why don’t we look at the long-term legacy of both the captured and the unknown?

Reduced side effects of PWM

If PWM switching is not acceptable for you, or you just want to check it out and make it easier to read if you need to change the switch, I recommend you try it now. Set the monitor brightness to maximum and turn on all automatic brightness adjustment mechanisms. Now change the brightness to a normal level (use the additional contrast level) using the additional color correction available in your video card drivers, or using an additional calibration device. This is to change the brightness and contrast of your monitor, in which case the backlight will be turned on for a maximum of three hours using PWM cycles. Although this method will not work well through changing the contrast, this technique can help to determine the level of positive influx by changing the PWM viscosity.

In the most efficient way, it would be necessary to add a display that does not use high-frequency PWM for brightness control, or would like to use high-frequency PWM. Unfortunately, it seems that the generators have not yet implemented PWM, which operates at frequencies that would be located between the detected optical defects (obviously, much higher than 500 Hz for CCFL and higher than 2 KHz for LED c). In addition, for some displays that contain PWM, the replacement ratio is not equal to 100% at full brightness, which is why the smell persists at any time. It is possible that for some publicly available displays with LED backlights, PWM is not detected, but unless the backlighting frequency and modulation are specified in the technical specifications, a particular display must be checked specifically .

Verification and analysis

It would be a miracle if we found a simple way to vary the PWM frequency of the feed, and, fortunately, for which there is enough camera with the ability to manually adjust the display. How to use this method yourself is described below.

Zjomka:

1. Set the settings on the monitor if you need to check them.
2. (Not required) Set the white balance on the camera if there is no white color displayed on the screen. However, it is not possible to manually set the white balance to approximately 6000 K.
3. Display on the monitor a thin white vertical dark brown on a black aphid (1-3 specks will be enough). It’s the fault of the buti that is visible from the image.
4. Set the camera's shutter speed to 1/2 to 1/25 seconds. To get enough light to capture the light, you will need to set the ISO sensitivity and aperture. Check that the dark brown is spread on the focal length (fix it as needed).
5. Position the camera at a distance of approximately 60 cm from the monitor and perpendicular to it. Press the shutter button while moving the camera horizontally towards the screen (be sure to keep them perpendicular to each other). You may need to experiment with camera movements on different lenses.

1. Adjust the brightness of the captured image so that it becomes clearer.
2. Enjoy the number of cycles shown in the image.
3. Divide this number by the size of the window display. For example, if you set the frequency to 1/25 seconds and set 7 cycles, the number of cycles per second is 25 * 7 = 175 Hz. This is the frequency of subswitching.

The essence of the technology is that by moving the camera during the shooting hour, we convert the time-hour effect into space. As a single element of light during the interview, there is a thin dark on the screen, which is drawn onto the light-sensitive matrix in the appearance of the people who go one after another. As the lights move around, different items will have different values ​​of brightness and color, which are assigned to the lights at a specific moment of capture.

A typical problem with the first tests is that this technique is too dark to darken the image. The situation in this regard can be improved by using a larger aperture on the camera (lower f/number) or increasing ISO sensitivity. The window does not allow the exposure to flow, leaving us vikoristically deprived of control over the undercurrent of the seizure. The brightness of the image can also be moderated by changing the speed of movement of the camera: higher speed will provide a darker image at a higher rate per hour, and ultimately lower speed The bones will be brighter than the image at lower levels.

Another problem that is becoming more pronounced is the uneven positions between adjacent areas in the resulting image as a result of changes in the speed of camera movement during the shooting hour. To achieve the best speed, start moving the camera about an hour before harvesting, and finish about an hour after it is finished.

The image, which looks exactly the same, may still be out of focus. In some situations, you can press the shutter button halfway to focus and then continue in the original mode.

Watching the monitor closely may cause additional effects. CCFL-based supplementation often shows different colors at the beginning and end of the skin cycle, which means that the luminophores that are vicorized react with different fluidity. LED-based backlighting often uses a higher frequency than CCFL backlighting, and you may need to move the camera further to increase cycles. The darkness of the dark between the cycles means that the steaminess of the PWM has been increased in such a way that during this part of the cycle the light is not compromised.

Dell 2007WFP (CCFL)

With a 1/25 second timer, we can clearly see 7 cycles, from which it appears that the light will move at a frequency of 175 Hz. In all honesty, there is a small amount of confusion, although you would like to drink a little for everything, so as to be unnoticeable. At half brightness, a small amount of shade appears, and when the minimum brightness is reached, there is a lot less shade in the order of the original color.

NEC EA231WMi (CCFL)

At full brightness, the sun is visible during the day. At half brightness, the depth and color of the surface become visible. With minimal brightness, beware of greater depth and value of colors. At a time of 1/25 seconds, approximately 8 cycles are visible, which indicates a frequency of approximately 200 Hz. With trivial vibration, a more precise frequency value is selected - 210 Hz.

Samsung LN40B550 Television (CCFL)

Turning on the automatic adjustment of brightness is not possible, this indicates the maximum and minimum levels of brightness that can be easily achieved. At full brightness, the sun is visible during the day. At minimum brightness there is a strong shade and color sound, which can be seen under the yellow and blue warehouses. With a vitrity of 1/25 seconds, only 6 cycles are visible, from which it appears that the illumination moves at a frequency of 150 Hz.

2009 Apple MacBook (LED)

With a 1/25 second exposure, visible shadow and color are visible every day, regardless of brightness. This display is not VICORIST PWM. The reason for borosin frequency is the noisiness of the image.

2008 Apple MacBook Pro (LED)

At a time of 1/25 seconds, beware of slight interference at high brightness. With a brightness of 50 and 0, even higher steaming is obtained, which gives greater depth. This LED backlight has a higher frequency - 420 Hz, but it is still too low to eliminate the shadow effect. Visible color grain throughout the daily cycles.

Visnovok

As we have indicated the beginning, this article was written not in order to discourage people from current PK displays, but in order to help people become aware of the potential problem associated with PWM. With the growing popularity of monitors powered by white light-emitting diodes (W-LED), an impressive number of consumers are likely to emerge in the modern world. These displays are connected to a different PWM method and, in the end pouch, to the selected type of lighting. Of course, the problems that can be caused by the presence of PWM are not noticeable to the skin, and in fact I realize that there are far more people who do not recognize the described symptoms than those who do. For those who suffer from side effects, including headaches and eye strain, now I would like an explanation.

Considering that this technology, such as PWM, has been used for a long time and successfully, and there are also a lot of successes in CCFL displays, I honestly doubt that in the near future anyone’s plan is going to change, This is the case when moving to the light LED. podsvichuvannya. PWM, as before, is a reliable way to control the intensity of illumination and also offers the possibility of regulating brightness, which is necessary for the skin.

Tim, who is worried about side effects or problems with the front displays, should try to determine the PWM frequency of his new display and perhaps try to find out the screen in which PWM to brighten up the display. Dsvichuvannya vzagali is not vikorystvuetsya. It’s a pity that we’ll still have to see how the generators begin to specify all the technical characteristics that the PWM frequency is based on, as well as its frequency at the highest levels of brightness, so it’s important to judge this at the same time.

Setting the screen to maximum brightness is one of the possible methods that can help reduce side effects and result in less scratchiness. The solution, of course, is not ideal, the fragments of many displays still have a high factory or maximum level of brightness, but there is nothing that can help. Changing the brightness in software or using the video card driver will help to increase the brightness to a more comfortable level, but may lead to a decrease in contrast.

There are no easy ways to check the performance of your monitor or TV before purchasing. In stores, consultants always emphasize the buyer’s respect for the size and size.

However, most of the experienced buyers believe that turning the screen onto a PWM interconnection with the help of a regular operator or pen allows you to avoid purchasing an unfavorable monitor, which is harmful to your health.

What is PWM?

PWM or pulse width modulation is one of the methods for changing the brightness level of a monitor or TV screen. The effect is created through the regular supply of pulses of previously established purity. When the screen is illuminated, it starts to flicker and flicker with a very fluid fluidity. It is important to notice this effect yourself.

Varto points out that the higher the frequency of the noise, the more easily people work with a laptop or computer.

You need to be victorious in order to reach a wide range of management options. In the opinion of the fakhivts, this is one of the most powerful, as well as simplest ways to achieve this goal.

Any object that is a light generator controls the shadow effect. Blame it on the lighting of the lamp.

The legislation of the Russian Federation stipulates that the coefficient of interference with the working place should not exceed 10-20% at a frequency below 300 Hz.

It does not matter that pulse width modulation typically operates at a frequency of 175 hertz, which can lead to significant negative changes in the operation of the monitor.

Why is it necessary to check the measure?

In advance, the main departments are in the process of checking the material and purchasing the necessary equipment. According to programmers, if the monitor moves regularly and continuously, then people who spend three hours studying for work can be very sensitive to other signs of illness, for example:

• This affects the health of our eyes. So, since the stench is steadily straining due to a steady pulsation, it can become noticeable;
• Also, one sign of a steady pulsation of the monitor is the appearance of a headache and drowsiness. In such a situation, it is even more difficult for people to concentrate on their work.

If you don’t care about those reliable devices that won’t harm your health, if the cost is many times more expensive, then you can give your advantage.

In order to check the screen of your monitor for the measurement that creates PWM, you must:

• to speed up with an oval or a hand;
• After which you will find an even lighter image, preferably a white color. If you do not have access to the Internet, you can open a text editor, such as Notepad, and open an empty document across the entire width of the screen. Make sure that most of the screen is white;
• Then take your olive or any long and thin object;
• Then spin it around 10-15 cm from the screen.

Since the outline of the sheep is practically invisible to you, then the thickness of the screen is minimal. This means that the brightness of the monitor screen is good. When you're working hard, you won't notice the strain on your eyes and body.

If the contour is clearly visible, then the pulsation of the screen light is even greater. Therefore, it is necessary to go through the steps to solve this problem.

How to clean up the mess

Experts confirm that the only way to fix this problem is to completely replace the screen with a new one. In this case, the idea is that it is possible to change the PWM - pulsation can be achieved by additionally changing the frequency of the circuit in adjustments. This way it will be easier for the kristuvachev to work on the computer.

There is also an alternative way to change the pulsation effect:

• To begin with, work so that the brightness of the screen is maximum;
• Next, turn it over so that the “Auto-adjustment” function is enabled;
• And then you need to know the color and contrast correction controls on the video card driver and change them to normal;
• In this way, we change the brightness and contrast of the screen, and the illumination of your screen allows your eyes to ignore all the darkness.

Varto note that such an effect is trivatime. If you are concerned about your health, it is best to get a monitor that has pulse width modulation. For example, an excellent option would be a screen whose height is several times higher, lower PWM.

How can YOU be fooled by the sale of monitors and TV. ROZVITOK:

Looks like AMOLED without interconnect (PWM) (updated periodically) July 25th, 2017

I want to buy a smartphone, what should I do?
TFT (as well as IPS, PLS, Super LCD) in 99% of cases does not move, but moves at a high frequency (totally imperceptible to the eyes).
So you can look at the models that you can click on on sites that conduct tests on PWM: S8+ and S7 Edge, in which the pulsation is set to zero brightness. One thing the author writes about is that at minimal brightness the mura defect begins to appear A Japanese word that indicates a defect, which is adapted in English to name defects in the pixel matrix of the display surface, which are visible when the display screen is permanently gray.

Why not buy Samsung now?
If you are going to read books in any way, it’s not Raja. In other cases, you may not notice anything serious. Axle of merkuvan:
The coefficient of interest for digital televisions (which have been used by more than one generation) can easily reach 250%, but you would hardly want to read Tolstoy’s “War and Peace” on them.
Perhaps, not surprisingly, the highest efficiency ratio I've seen on large AMOLED displays (5.5 inches and larger). Well, as hygienists (as there are such fakers in the Samsung staff) know that the use of a very weak, or large display, costs about the same as the use of a small display with a lower coefficient of motion Innya?

All current TVs with RK screens use LED lighting - the lamps were lost last year. When the brightness of the switch is set to 100%, the pulsation starts every day - the LEDs operate under constant voltage. Although the hundred-hundred-hundred-hundred-hundred-hundred-hundred- de deceth candle is good only in the store - at home such brightness appears supernatural, and it is necessary to change it.

To regulate the brightness of the illumination, pulse width modulation (PWM) is first used - the LEDs turn on and off at a frequency of one hundred to several thousand times per second. Corresponding to the hour when the LED is on (after the turn-on pulse) and the hour when it is off (after the pause between the pulses), it means average brightness.

If the frequency of the pulses is low (100 or 120 hertz), the pulsation of the light can be noticed with a quick glance or quickly shifting the gaze from one point to another. It is important that pulsation with a frequency of up to 300 Hz stimulates the eyes and brain and can lead to headaches and severe nerve diseases. In addition, there is a thought that a decrease in brightness with the help of additional PWM calls out a subdivision of the eye reticle through those that expand, oriented towards the middle level of brightening, and the reticle is removed “hit” with light pulses of maximum brightness.

Having equipped myself with a camera that records video at a speed of 1200 frames per second, I went to electronics stores and checked how the matrix is ​​processed in 42 models of televisions from six receivers.

On store displays, all TVs are now operating at 100-cell brightness, so before we die, I reduced the brightness of every TV to 30-50%.

Let me start with the good news - all tested Sony TVs did not show backlight pulsation. Great for everything, there is a very high PWM frequency (tens of thousands of interruptions per second). I checked the following models:

• Sony KDL-32RE303,
• Sony KDL-32RE403,
• Sony KDL-32WD752,
• Sony KDL-32WD756,
• Sony KDL-40WE633,
• Sony KDL-43WF665,
• Sony KDL-43WE755,
• Sony KDL-43WF804,
• Sony KDL-43XF8096.

In the video, magnified 40 times, the TV screens of LG 32LH570U (left-handed) and Sony KDL-32RE303 (right-handed) with 30% sensitivity look like this:

There was also no pulsation on the Chinese Haier TVs, but the reason for this is even more banal: they simply have no regulation of the brightness of the backlight - it will never burn again. I protested two models:

• Haier LE32B8500T,
• Haier LE39B8550T.

Panasonic TVs are now readily available in stores, but two 32-inch models have yet to be revealed. Moreover, the stench appeared completely different. At the cheap one Panasonic TX-32DR300 The detection is high at three times the frequency of the signal (150/180 Hz), in the road Panasonic TX-32ESR50 pulsation is present throughout the day.

The pulsation of the backlight of Samsung TVs depends on the model. Quite cheap TV sets, including younger models of the sixth series, have a hundred hundredth pulsation at a frequency of 100/120 Hz (the frequency of the pulsation is twice the frequency of the input signal ). In the center of the Samsung UE43NU7140U video, enhanced 40 times:

Such pulsation was detected in the following TV models:

• Samsung UE32J4710,
• Samsung UE43J5202,
• Samsung UE43M5513,
• Samsung UE43NU7140,
• Samsung UE43NU7170,
• Samsung UE49M5500.

Models of the sixth series of Samsung 2017 behave completely differently. They have daily pulsation when the brightness of the backlight is reduced to the singing level (probably, the flow is regulated through the LEDs), and when the backlight level is further reduced, PWM is turned on. In younger models (MU61**), there is no pulsation at switching levels of 13-20, and at levels 0-12, the PWM frequency becomes 100/120 Hz. In older models (MU64 **, MU65 **), there is no pulsation at switching levels of 10-20, and at levels 0-9, the PWM frequency is 200/240 Hz.

Samsung 49MU6650U, brightness 50% (10 out of 20 on the adjustment scale):

The same TV with a brightness level of 25% (5 out of 20 on the adjustment scale):

I protested the following models:

• Samsung UE40MU6100,
• Samsung UE40MU6400,
• Samsung UE40MU6470,
• Samsung UE55MU6470,
• Samsung UE49MU6650.

These TVs can generally be classified as flicker free, since the level of illumination is reduced to 50-65%, which is entirely sufficient – ​​and in this case the pulsation is daily.

On a QLED TV Samsung QE49Q7 A dark shadow runs across the screen 100 or 120 times per second, the width of which is greater, the lower the brightness of the backlight is set:

It’s much clearer when you enlarge the video not by 40, but by 120 times:

The pulsation is much more gentle on the eyes, and the switching on of the backlight is lower.

The least active TV was the eighth series Samsung UE55NU8000U. Marvel at yourself (increased in 120 times):

At a frequency of 180 Hz, the pitch changes per red. Importantly, for lighting your TV will need RGB LEDs.

In all LG RC TVs I tested in the lower and middle price ranges, with reduced brightness, the backlight pulses at a frequency of 100/120 Hz. The axis, for example, LG 32LJ610V:

• LG 32LJ500,
• LG 32LJ510,
• LG 32LH570,
• LG 32LJ600,
• LG 32LJ610,
• LG 32LK6190,
• LG 43UK6750,
• LG 49UJ634.

The older LG models operate in a completely different way. In the center of the screen the sides are dark and dark. The axis looks like this LG 49SJ810 at 40-fold increase:

The entire cycle is repeated 100/120 times per second. With a 120-fold increase, you can increase the lighting by dividing it into six zones that go out in pairs.

This kind of robotic switching is fixed in the following models:

• LG 43UJ750,
• LG 49UJ740,
• LG 49SJ810.

Russia recently acquired TVs from the Chinese brand Hisense. In cheap models, the backlight shines with a three-time signal frequency (150/180 Hz).

In the midst of my protests, I use the following models:

• Hisense H32A5600,
• Hisense H43A6100,
• Hisense H50A6100.

In the video, amplified 48 times, you can see how the smoothie shines Hisense H50A6100 It’s a shame to see new things running on the expensive LG, right-handed on the Samsung QLED.

The road Hisense models have a higher PWM frequency. At 40 times the pulsation of the Hisense H55N6800 looks like a blink:

All TVs protested:

I don't know why the manufacturers of most TVs rely on PWM, which operates at a frequency of 100/120 Hz. At first glance, there is no point in increasing this frequency by ten times a hundred times. Perhaps, for some reason, this will happen, after which we will begin to hear about the “revolutionary technology” of Flicker Free.

You can check the presence of visible pulsation on a TV screen without special equipment. Reduce the lighting level to the minimum level (the lighting level itself, not brightness!). Turn the olive in front of the screen (amazing olive test). Although there is no stroboscopic effect and you can see the image of the image, there is no visible pulsation (or there is no pulsation at all, or the PWM frequency is higher than 300 Hz). If you experience a stroboscopic effect - the olive “breaks up” into many olives - pulsation.

There is only one way to make the RC TV screen pulsate without any further processing - turn on all eco modes, set the backlight level to 100% and reduce brightness to achieve a comfortable picture. The black color will become gray and the picture will be faded, and the eyes without pulsation will become less blue.

Nowadays we are gradually switching to laptops and tablets, but rather the classic desktop. With a monitor, a system unit, an MFP and a computer desk under everything. Hello, on the monitor with the light-emitting diodes I heard a bevel sound. Yes, thin. Yes, inexpensive. But their eyes are watching them, that’s a fact. However, as it turned out, not everything was so bad. And, while the majority of videographers are wondering who has the brightest light, they are still working on it to make their monitors gentle on the eyes of their clients.

Why do my eyes turn on the speed of some monitors, but not others? In essence, the monitor is like a spotlight that constantly shines on your face. The more brightly the light shines, the more the eyes are drawn. It’s not at all a fact that this “spotlight” is less bright, if in settings you turn the brightness indicator to a minimum. The brightness does not change, the light just gradually fades. It will turn on for the first time (to the point of tension again), and then fade away. Visual brightness will change. The picture will fade. And your eyes will be as bright as they are 100% bright. And if you don’t take a break, you may get a headache. This technology is called pulse width modulation or simply PWM. And on the Internet, before speaking, people often ask questions: “How can I find a monitor without a PWM switch?”.

I added nutrition for a long time, and realized that others have the right to fight against the shortcomings of the PWM, BENQ came up with its technology for controlling the LED switches for an additional change voltage of stationary current. In this way, it seems absolutely obvious (it would seem) the solution is that the LEDs should glow steadily, and the stronger the voltage that is supplied to them, the brighter the stench will burn. Regardless of any hardware tricks, the temperature does not change significantly. The technology itself was called Flicker-Free, and the method of implementation was DC dimming. More detailed information can be found in the video below. There, at 2:50 seconds, a couple of ways to detect PWM are introduced:

At the same time, two models from the line of BenQ monitors received the eye care branding: GW2760HS (27 inches, A-MVA, price around 10,500 rubles) and BL2411PT (24 inches, IPS, market price 15,200 rubles. ). According to the authoritative formulations of BENQ representatives, Eye care is a set of parameters, including:
- "Flicker-Free" function;
- “Reading” mode, which allows you to have a modern look of a traditional hand-held paper, which makes viewing texts very comfortable and not tiring for your eyes;
- Eco mode, which ensures pleasant image brightness while maximizing energy savings (reduces energy consumption by 37% when viewing documents, web pages and up to 44% when viewing computer games).

Although the decision was made by other pickers, I couldn’t find anything of equal value. Try to implement a technology similar to Flicker-Free, of course. Well, as a matter of fact, the models either suffer from serious problems when looking at them and transfer colors, or they have an unpleasant high-frequency hum, or they are glossy like mirrors and stand shamelessly. If I missed something, you can correct me in the comments - it will be helpful. According to BENQ, according to company representatives, they plan to transfer all upcoming new products to Flicker-Free. So, I will take my upcoming monitor from its source.