Basic parameters of LCD monitors. Main types of monitors. Types of modern monitors

1) Screen working area size

The nominal screen diagonal size of an LCD monitor is equal to the visible area, in contrast to a CRT monitor, the visible area of ​​which is always smaller.

Monitor manufacturers, in addition to the physical dimensions of picture tubes, also provide information about the dimensions of the visible part of the screen. The physical size of a kinescope is the outer size of the tube. Since the kinescope is enclosed in a plastic housing, the visible size of the screen is slightly smaller than its physical size. So, for example, for a 14" model (theoretical diagonal length 35.56 cm), the useful diagonal size is 33.3 - 33.8 cm depending on the specific model, and the actual diagonal length of 21" devices (53.34 cm) is from 49.7 to 51 cm.

2)Radius of curvature of CRT screen

Modern picture tubes are divided into three types according to the shape of the screen: spherical, cylindrical and flat (Fig. 1).

Spherical screens have a convex surface and all pixels (points) are at an equal distance from the electron gun.

A cylindrical screen is a sector of a cylinder: flat vertically and rounded horizontally.

Flat screens are the most promising. Installed in the most advanced monitor models. Some picture tubes of this type are not actually flat - but due to the very large radius of curvature (80 m vertically, 50 m horizontally) they look really flat.

3) Screen coating

An important parameter of a kinescope is the reflective and protective properties of its surface. If the surface of the screen is not processed in any way, then it will reflect all objects located behind the user’s back, as well as himself. In addition, the flow of secondary radiation that occurs when electrons hit the phosphor can negatively affect human health.

The most common and affordable type of anti-glare screen treatment is silicon dioxide coating. This chemical compound is embedded into the surface of the screen in a thin layer. If you place a silica-treated screen under a microscope, you will see a rough, uneven surface that reflects light rays off the surface at different angles, eliminating glare on the screen. The anti-reflective coating helps you perceive information from the screen without strain, making this process easier even in good lighting. Some picture tube manufacturers also add chemical compounds to the coating that act as antistatic agents. The most advanced screen treatments use multi-layer coatings of various types of chemical compounds to improve image quality.

4) Vertical frequency

The monitor's vertical scan frequency shows the maximum number of horizontal lines on the monitor screen that an electron beam can draw in one second. Accordingly, the higher this value (namely, it is usually indicated on the monitor box), the higher the resolution the monitor can support at an acceptable frame rate. The maximum line frequency is a critical parameter when designing an LCD monitor.

5) Horizontal Frequency

This is a setting that determines how often the screen image is redrawn. Horizontal frequency in Hz. In the case of traditional CRT monitors, the glow time of the phosphor elements is very short, so the electron beam must pass through each element of the phosphor layer often enough so that there is no noticeable flickering of the image. If the frequency of such a bypass of the screen becomes less than 70 Hz, then the inertia of visual perception will not be enough to prevent the image from flickering. The higher the refresh rate, the more stable the image on the screen appears. Flickering images lead to eye fatigue, headaches and even blurred vision. Note that the larger the monitor screen, the more noticeable the flickering is, especially in peripheral (side) vision, as the viewing angle of the image increases. The horizontal scan frequency value depends on the resolution used, the electrical parameters of the monitor and the capabilities of the video adapter.

6) Dot pitch

Dot pitch is the diagonal distance between two phosphor dots of the same color. This size is usually expressed in millimeters (mm). Aperture grid picture tubes use the concept of stripe pitch to measure the horizontal distance between phosphor stripes of the same color. The smaller the dot pitch or bar pitch, the better the monitor: images look clearer and sharper, contours and lines are smooth and elegant. Very often the size of the dot on the periphery is larger than in the center of the screen. Then manufacturers indicate both sizes.

7) Permissible viewing angle

D For LCD monitors, this is a critical parameter because not every flat panel display has the same viewing angle as a standard CRT monitor. Problems associated with insufficient viewing angles have long held back the adoption of LCD displays. Because light from the back of the display panel passes through polarizing filters, liquid crystals, and alignment layers, it exits the monitor mostly vertically oriented. If you look at a regular flat-panel monitor from the side, you either cannot see the image at all, or you can still see it, but with distorted colors. In a standard TFT display with crystal molecules oriented not strictly perpendicular to the substrate, the viewing angle is limited to 40 degrees vertically and 90 degrees horizontally. Contrast and color vary as the angle at which the user views the screen changes. This problem has become increasingly important as LCD displays have grown in size and the number of colors they can display. For bank terminals, this property is, of course, very valuable (as it provides additional security), but it brings inconvenience to ordinary users. Fortunately, manufacturers have already begun to use improved technologies that expand the viewing angle. They allow you to expand the viewing angle to 160 degrees and above, which corresponds to the characteristics of CRT monitors (Fig. 2). The maximum viewing angle is considered to be the one where the contrast ratio drops to a ratio of 10:1 compared to the ideal value (measured at a point directly above the display surface).

8) Dead spots

Their appearance is typical for LCD monitors. This is caused by defects in the transistors, and on the screen such non-functioning pixels appear as randomly scattered colored dots. Since the transistor is not working, such a point is either always black or always glowing. The effect of image damage is enhanced if entire groups of dots or even areas of the display do not work. Unfortunately, there is no standard that specifies the maximum permissible number of non-working dots or groups of dots on the display. Each manufacturer has its own standards. Usually 3-5 non-working points are considered normal. Buyers should check this parameter upon receipt of the computer, as such defects are not considered a manufacturing defect and will not be accepted for repair.

9) Supported Resolutions

The maximum resolution supported by the monitor is one of the key parameters; it is specified by each manufacturer. Resolution refers to the number of elements (dots) displayed on the screen horizontally and vertically, for example: 1024768. Physical resolution depends mainly on the size of the screen and the diameter of the screen pixels (grains) of the cathode ray tube of the screen (for modern monitors - 0.28-0.25). Accordingly, the larger the screen and the smaller the grain diameter, the higher the resolution.

10) Body and stand design

The design of the monitor should provide the possibility of frontal viewing of the screen by rotating the housing in a horizontal plane around a vertical axis within ±30° and in a vertical plane around a horizontal axis within ±30° with fixation in a given position. The design of monitors should include coloring in calm, soft tones with diffuse light dispersion. The monitor body must have a matte surface of the same color with a reflectance coefficient of 0.4 - 0.6 and not have shiny parts that can create glare.

11) How to connect a monitor to a computer

There are two ways to connect a monitor to a computer: signal (analog) and digital.

The monitor requires video signals that carry the information displayed on the screen. A color monitor requires three color encoding signals (RGB) and two clock signals (vertical and horizontal). To connect the monitor to the computer, signal (analog) cables of various types are used. On the computer side, such a cable in most cases has a three-row DB15/9 connector, which is also called a VGA connector. This connector is used in most IBM-compatible computers. Apple Macintosh computers use a different connector, the DB15 dual-row connector. In addition, there are special coaxial cables.

For convenience, some monitors have two switchable input interfaces: DB15/9 and BNC. Having two computers, you can use one monitor to work with two computers (of course not simultaneously).

In addition to the signal connection, it is possible to connect the monitor to a computer via a digital interface, which allows you to control the monitor from the computer: calibrate its internal circuits, adjust geometric image parameters, etc. The most commonly used digital interface is the RC-232C connector.

12) Controls and regulation

Control means adjusting parameters such as brightness and image geometry on the screen. There are two types of monitor control and regulation systems: analog (knobs, sliders, potentiometers) and digital (buttons, on-screen menu, digital control via a computer). Analog control is used in cheap monitors and allows you to directly change electrical parameters in the monitor components. Typically, with analog control, the user only has the ability to adjust brightness and contrast. Digital control ensures the transfer of data from the user to the microprocessor, which controls the operation of all monitor components. Based on this data, the microprocessor makes appropriate corrections to the shape and magnitude of the voltages in the corresponding analog nodes of the monitor. Modern monitors use only digital control, although the number of controlled parameters depends on the class of the monitor and varies from a few simple parameters (brightness, contrast, primitive adjustment of image geometry) to a super-extended set (25 - 40 parameters) that provide precise settings.

A computer monitor is a device designed to display visual (graphic, text, video) information.

Also, some monitors have built-in sound speakers and can thus reproduce sound, but this feature is not included in the main characteristics of the monitor.

When purchasing or assembling a personal computer (PC) from separate ones, you should definitely pay attention to the characteristics of the monitor, which we will consider below.

Previously, a monitor was called a display; now this name is rarely used.

1 Diagonal length and proportions of the monitor

Diagonal is measured in inches. 1 inch is equal to 2.54 centimeters. Previously, the measurement (“standard”) of an inch was the width of the thumb on an adult man’s hand. An inch when indicating the diagonal of a monitor is represented by a quotation mark “ - in the form of a double stroke. In English, inch is inch, abbreviated as in.

Most often you can find monitor models with diagonals of 15”, 17”, 19”, as well as 21”, 23” and 27 inches. The last option (27”) is more suitable for professional designers, photo editors, video editors, etc. Of course, ordinary users can also use it if they have the opportunity and desire to have a large monitor.

Monitors may have the same size in inches, but they will differ in proportions (Fig. 1).

Rice. 1 Monitors have the same diagonal, but different proportions

As for the proportions (the ratio of the length and width of the sides of the monitor), three formats are most widespread -

• 16:9,
• 16:10,

These numbers mean the following. 16:9 - this means that the width of the monitor (horizontally) is 16 conventional units, and the height of the monitor (vertical) is 9 of these same conventional units. More precisely, the width of the monitor is greater than its height by 16 divided by 9 times, that is, 1.78 times.

And, for example, a ratio of 4:3 means that the width is greater than the height by only 4 divided by 3 times, that is, 1.33 times.

Monitors with an aspect ratio of 16:9 and 16:10 are widescreen. They are good for watching widescreen and widescreen video movies. It is convenient to open several windows at the same time.

Monitors with an aspect ratio of 4:3 are convenient for those who work with editors, with graphic files, etc., but for others they are more familiar.

Monitors with an aspect ratio of 4:3 are often more convenient for work, and 16:9 for entertainment. Nowadays, widescreen monitors are also used more often for work, simply because they are more common.

Rice. 2 Two monitors in one case

Widescreen monitors are convenient for those who like to work with several at once. Such users often use PC configurations with 2 (Fig. 2) or even 3 monitors at the same time.

The diagonal length and proportions of the monitor are what users pay attention to first, but the main characteristics of the monitor, of course, do not end there.

2 Type

Currently, there are only two main types of monitors:

CRT monitor

As for CRT, this abbreviation stands for “cathode ray tube”.

These monitors are similar to old TVs (they are almost the same size and weight). They are older and rarely used anymore due to their large size, energy consumption and harm to the eyes.

Cathode ray tubes use high voltage, fast charged particles, and other technical things that are more harmful to users than more modern LCD displays.

LCD is an abbreviation for Liquid Crystal Display, which translates as liquid crystal display.

LCD monitors are more compact and lightweight because they can be almost flat in shape. Therefore, today they are used almost everywhere.

LCD monitor

The picture on LCD monitors is formed from a set of small dots (pixels), each of which can have a specific color. There are no harmful effects on the user and his eyes that cathode ray tubes had.

The first models of LCD monitors were slow, they could not reproduce fast-changing images without distortion, and therefore for a while cathode ray displays were competitive. However, technology does not stand still, and modern LCD monitors no longer have the disadvantages of their predecessors.

Today, when buying a monitor, you can see a varied range of exclusively LCD displays. Cathode ray tubes are becoming a thing of the past.

3 Resolution

This is the number of pixels (the dots that make up the display) vertically and horizontally. The more pixels, the higher quality image can be obtained. And vice versa, the fewer there are, the more blurry, less clear, and lower quality the image will be. Therefore, if you want to see clearer pictures, you need to have more pixels.

In general, a pixel is the smallest point on a monitor screen. The whole picture is made up of such points. The more dots and the fewer these dots, the clearer the image. Hence the need to have more pixels to get better quality images.

Typically, resolution depends on the size of the display and its aspect ratio. For example, you can often find:

• 16:10 format monitors have a resolution of 1440x900,
• for 4:3 format monitors – resolution 1600x1200,
• 16:9 format monitors have a resolution of 1920x1080.

Numbers, for example, 1920x1080 mean:

– horizontally the monitor has 1920 pixels – the minimum points from which the image is composed,

– the monitor has 1080 pixels vertically,

– in total there are: 1920 multiplied by 1080 equals 2,073,600 pixels, that is, more than 2 million tiny dots, from which a beautiful, clear color image is formed.

In addition, the term pixel density is often used. Density is calculated using the formula “the number of points on any side divided by the length of this side.” This is needed to represent how many pixels are in one millimeter or one centimeter of the screen. But, as a rule, people have already gotten used to pixels, so the phrase “pixel density” is used much less often.

4 Matrix type

There are many types of matrices, they are not so easy to understand. They depend on the manufacturing technology of the matrix, and due to this they differ from each other in image quality, viewing angle, speed of image change and other parameters.

The viewing angle means that in some places the image is visible from all sides, and in others strictly at almost a right angle, so that the “neighbor” cannot see what is shown on your monitor.

The following types of matrices are distinguished:

– relatively inexpensive, but not the highest image quality TN+film panels. Their disadvantage is small viewing angles (move a little to the side and you won’t see anything), a decrease in brightness and contrast if you look at the image from the side and not at a right angle, etc.

– numerous IPS matrices with different nuances and differences from each other, having wide viewing angles, deep blacks, and good color rendition. Various types of such matrices can have both short (bad, slow) and fast (good, high-speed) response times, which allows slow matrices to be used for office work, and fast ones for watching videos, games and other applications that require fast graphics .

– VA matrices, PVA matrices and other types of matrices that differ from each other in response time (speed), color rendering, viewing angles and other characteristics.

5 Contrast level and viewing angle

Contrast is measured by comparing the brightness of the monitor's white and black pixels. The average value of this indicator is 1:700. The numbers mean that the brightness of black pixels is 700 times less than the brightness of white pixels, which is a very respectable value. Although now it is quite common to find monitors with a contrast ratio of up to 1:1000.

The viewing angle affects from what position in relation to the monitor you can easily distinguish the picture. Many modern monitors have a viewing angle of 170-175 degrees.

We remember from school geometry that 180 degrees is a rotated angle, that is, looking at the monitor tangentially to its plane. Therefore, a viewing angle of 175 degrees is an opportunity to see the image even when standing to the side of the monitor. In other words, the picture is visible even if you direct your gaze almost parallel to the display.

6 Pixel response time

Also quite a significant indicator. The shorter the response time, the faster the picture will change (pixels will respond faster to the signal).

High-quality modern monitors have a response time of 2-9 milliseconds. The number 9 milliseconds means that the image of each pixel can change more than 100 times per second.

And the number 2 milliseconds means the ability to change the image of each pixel 500 times in 1 second! We remember that the human eye no longer has time to distinguish between changes in a picture with a frequency of more than 24 times per second, and therefore 500 times per second is a very good result!

The faster the response, the better quality moving pictures the monitor can reproduce. Therefore, fans of computer games and those who like to watch high-quality films on a monitor screen prefer monitors with a high response time, and are willing to pay extra money for this quality.

7 Connectors and ports for connecting a monitor

An important point when choosing a monitor is the option of connecting it to a computer. First of all, you need to know what connectors are on the computer.

If the monitor is selected for a desktop PC, then the computer may have different ports, for example DVI, VGA, HDMI.

Laptops usually use a VGA port to connect an external monitor.

But Apple computers use ports such as Mini DisplayPort and TunderBolt. All this should be kept in mind when choosing a monitor.

As a rule, monitors have the ability to connect to a DVI and (or) VGA port, but this must also be clarified.

If you need to connect the monitor to other ports, you may need special adapters with which the monitor can be connected to the computer. And then you need to take care of these adapters in advance.

Survey

The choice of any computer or any component begins with determining the criteria, which in this case
are technical specifications. Agree, when buying, for example, a monitor, the definition of “to show it well” is not enough, you need to know what size display is needed, with what resolution, how it will be connected, for what purposes it will be used (for games, office work). To answer these and a number of other questions, you need to know what characteristics monitors have, which ones are important, which ones are not so important, and which ones are usually silent about in official specifications.

Let's briefly list the characteristics that each monitor, without exception, has. Let's make a small guide with a brief description of what it is, how important the parameter is, what it affects, and what values ​​it is advisable to strive for.

Unfortunately, not all characteristics can be found in the descriptions of a monitor, be it a laptop screen or a display for a desktop PC. At the same time, among those parameters that are usually hidden, there are very interesting ones that can affect the image quality.

1. Matrix type

2. Screen resolution

This is the vertical and horizontal size of the screen in dots (pixels). The most popular and commonly found screens in laptops have FullHD resolution (1920×1080). In addition to this, there are a large number of other resolutions, some of which are more common, some less common.

Physically, this characteristic means the number of pixels on the screen that make up the image. The more pixels per unit of screen area, the better the picture, in theory, because the pixels become smaller and less and less noticeable. The “graininess” of the image disappears.

At the same time, we should not forget about the cost. The higher the resolution, the higher the price (in this case, I am using a kind of average display, and I am not comparing a high-quality screen with a lower resolution with a budget one, but with a higher resolution).

If we are talking about a gaming laptop or monitor, then there is another point to consider. When using GTX 1070/1080 class video cards in almost any game, you can set the graphics settings to maximum or close to it.

If the screen has a resolution of 4K (3840 x 2160), then in order to enjoy the picture in games at maximum graphics settings, GTX 1070/1080 video cards may no longer be enough. You may need to install a couple of such video cards, or even more.

3. Brightness

Indicated in the specifications for any monitor. This is a value measured in cd/m2 (candelas per square meter). Actually, what this characteristic is is clear from the name. Strictly speaking, the higher the value of this parameter, the better. Adjusting the screen to reduce its brightness is not difficult.

As for laptop screens, this parameter is also important for the reason that the very design of this type of computer allows it to be used not only in an office or at home, but also on trips, on the street, where the bright sun or other light source will illuminate the image on screen.

At low brightness values, it will be difficult to use such a screen in bright light. If the maximum value corresponds to 300 cd/m2 or even higher, this means that bright sunlight will not be a problem. In the end, it’s better to have a reserve of brightness, because it can always be reduced, but adding something that is not there, alas.

4. Contrast

This parameter reflects the ratio of the brightness level of white to black. It is usually specified as a ratio, for example 1000:1. As with brightness, the higher this value, the better. The image will be more natural.

Contrast depends on the matrix manufacturing technology. Thus, IPS screens are inferior in this parameter to screens made using VA technology, not to mention OLED, quantum dots, etc.

Conventionally, we can assume that screens with a contrast ratio of 500:1 or less can be classified as mediocre. It is better to focus on values ​​of 1000:1 and higher. Especially if in your work you have to deal with image editing, colorization, etc.

5. Dynamic Contrast

This parameter is almost always indicated, at least for regular, non-laptop monitors. Agree that not including in the specifications, for example, the value 100000000:1 is an omission. Big numbers attract attention and appeal to potential buyers (as long as it's not the price).

What does this characteristic mean? This is the result of the monitor electronics working to adjust the image at each moment in time in order to improve the “picture”. The brightness of the lamps is controlled in order to achieve high image contrast.

I would not pay much attention to this parameter, since this is more marketing than a real characteristic that speaks about the merits of a particular monitor. Moreover, no matter what display you choose, it’s difficult to count the number of zeros in the dynamic contrast value, and it’s not necessary.

6. Black depth

But this parameter is rarely indicated in the technical specifications, although it affects the image quality. When using the monitor under normal conditions, in daylight or artificial lighting, this parameter may be difficult to evaluate.

Another thing is that if you display a black picture on the screen, then at a low level of external lighting, or in complete darkness, it will become noticeable that the black color is somehow not quite black, and may even look more like gray. Some areas of the screen may be brighter than others.

This is all due to the fact that a backlight is used to produce images on the screen of LCD monitors, and to display black, it is not turned off, but is blocked by rotating the crystals in such a way that they do not transmit light.

Unfortunately, they ALMOST do not transmit light; some of the light still overcomes this barrier. In the above picture you can see that the black color still has some kind of gray tint.

Again, a lot depends on the matrix manufacturing technology. Blacks on VA screens are more similar to black than on IPS, for example. Of course, a lot depends on the quality of the matrix used, settings, adjustments, but in general this is true. OLED screens, based on quantum dots and other new technologies, cope best with black color.

With a certain degree of error, black level can be calculated by dividing brightness by contrast. For example, with a screen brightness of 300 cd/m2 and a contrast of 1000:1, we get a value of 0.3. This means that black pixels will glow (in theory, they should not glow at all, and only in this case can we talk about a truly black color) with a brightness of 0.3 cd/m2.

I hope it is clear that the lower this value, the better, the “blacker” the black color will be, forgive the tautology.

7. Screen surface type

Looking at the monitors themselves, you will notice that some of them are glossy, the surface shines and has a mirror effect. Other screens, on the contrary, reflect practically nothing and cope well with glare. There are two types of surface - glossy and matte. You can also find semi-gloss models, but these are attempts to combine the advantages of both types, reducing the disadvantages inherent in each of them.

So, the undoubted advantages of gloss include better brightness and contrast, better color rendition, the image is perceived more clearly. Those who work with images should prefer this type.

There are also disadvantages to glossy screens. This, of course, is glare and reflections of bright objects - lamps, light windows, etc. This can tire the eyes. Such screens are not suitable for laptops that are often used outdoors in bright sunshine. Another unpleasant feature is the unauthorized collection of fingerprints by screens with such a surface, as well as other contaminants. It is better not to poke your fingers at the screen, so as not to constantly wipe off the remaining marks.

Matte screens “by definition” do not reflect glare, they behave better in bright light, but this comes at the expense of worse contrast and color rendition. There is another drawback characteristic of matte screens: the “crystalline effect”. It manifests itself in the fact that the displayed point does not have clear boundaries, but may have some uneven edges with different shades.

How noticeable it is depends on your vision. For some, such “crystals” literally catch the eye, while others don’t even notice them. However, image clarity suffers from this.

8. Response time

A parameter that is almost always specified. For those who love games, this is one of the main screen options. The response time determines how clear the picture will be in dynamic scenes. It appears, for example, in the form of trails that trail behind image elements quickly moving across the screen. The shorter the response time, the better.

This parameter depends on the manufacturing technology of the matrix used in a particular display. So, the fastest ones are TN screens, and this is perhaps the only (if you do not take the cost) reason that this type of display has not yet “died”. IPS are slower, and VA are between these types of matrices in terms of response speed.

If the screen is selected for office work, surfing the Internet, watching videos, working with images, then this parameter is not very important. Now, if you are a true lover of virtual battles, then a screen with minimal response time is a must. And here you can even put up with worse color reproduction and unimportant viewing angles for TN matrices. Their response time is the shortest.

9. Viewing angles

As the name suggests, this means at what angle you can look at the screen at which the image does not lose color or brightness, or the quality of the picture deteriorates. Here the obvious outsider is TN matrices. The peculiarities of the technology are such that it is impossible to get closer to the maximum values.

But IPS panels do well with this. Viewing angles of 178° both vertically and horizontally are common. Frankly speaking, at such a large angle the image still deteriorates, but there are no such catastrophic consequences as with TN. VA matrices are closer to IPS, although slightly inferior to them.

How important this parameter is depends on how the monitor is used. If you are not going to watch videos from YouTube or those taken at the last party with a large group, but are using the monitor in splendid isolation, then viewing angles are not so important.

10. PWM

A characteristic that is almost never specified. (English - PWM)? This is Pulse Width Modulation, which is used to adjust the brightness of the screen. What is the essence of the emerging problem?

As I already mentioned when talking about black depth, LCD monitors use a backlight. The maximum brightness of the screen is not always needed, and it needs to be reduced. How can I do that? In at least two ways:

• Reduce the brightness of the backlight lamps/LEDs.
• Make light sources turn on and off by sending pulses to them with a certain frequency and duty cycle, which is perceived as a decrease in the brightness of the glow.

The second option is PWM brightness control. Why is he bad? This very flickering of lamps. It is good if the flicker frequency is high and amounts to tens of kHz. It’s not bad if the pulse amplitude is small. It's worse when the flicker frequency is low, and it can become noticeable to the eye.

The operating principle is as follows. To reduce the brightness of the screen, pulses are applied to the backlight lamps in such a way that they are turned on part of the time and off part of the time. For example, at 50% brightness, the llamas are on half the time and off half the time.

The resulting value of the ratio of the time when the backlight is on to the time when it is off will be one or another level of screen brightness. With a further decrease in brightness, the lamps' glow time decreases, and the time they are off increases. The flickering becomes more noticeable.

Naturally, a lot depends on individual vision characteristics. Some people react little to such flickering, while for others, after a couple of hours, figuratively speaking, their eyes begin to “bleed out.”

Be that as it may, the presence of PWM is a minus of the monitor. Unfortunately, you can find out about the presence or absence of this unpleasant effect either from reviews or reviews of a particular display, or check it yourself. You can conduct a simple test, which is called the “pencil test”.

The point is that you need to take an ordinary pencil and wave it like a fan in the plane of the screen. Naturally, the display must be turned on. If, when moving quickly, the outlines of the pencil are visible, then, unfortunately, there is flicker. If the contours are not visible, then there is no flicker. The test should be repeated at lower brightness values.

If the selected monitor has PWM, then if there are detailed reviews, it is better to find out how it works. If the pulse frequency is high, or PWM is used only at low brightness values, for example, from 0 to 25-30%, and then direct control of the brightness of the backlight lamps is used, then this is not so bad.

Now, if you look at the monitor models offered, some of them have the designation “Flicker free”, i.e. no flicker. I haven’t seen this designation on laptops, but it does occur on regular monitors. This marking means that there is no flickering, and this is an additional plus to the display model.

11. Color gamut

Another characteristic that is not always indicated in the specifications for a monitor, but the value of which may turn out to be one of the decisive arguments in favor of a particular model. Most often, it is indicated when the manufacturer wants to emphasize the high quality of the matrix installed in a laptop or monitor.

I think it makes sense to devote a separate article to this issue, but now I’ll tell you briefly. You've probably seen a similar picture in reviews of laptops or monitors. This is a color gamut chart for the Dell XPS 15 laptop screen.

This multi-colored area is what the human eye sees, the colors and shades that we can distinguish. The triangles inside indicate the range of colors displayed by a specific monitor, as well as boundaries that correspond to accepted color space standards for computer equipment: monitors, printers, etc.

The two most commonly used color spaces are:

• sRGB is a standard developed in 1996 by HP and Microsoft. Covers a small portion of the color space accessible to human vision.
• Adobe RGB is a standard that is wider than sRGB and covers more colors.

Typically, color gamut is expressed as a percentage of a particular standard. Thus, a screen covering about 60% of sRGB can be called mediocre, since it is difficult to obtain reliable color reproduction on it. It’s good for office work, surfing the Internet too, but this monitor is not suitable for image editing. Here we need displays with a color gamut of about 100% sRGB and higher.

As a conclusion, if you want a good picture with natural colors, then the color gamut needs to be as wide as possible, the higher the value, the better.

12. Color depth

Another parameter that is difficult to find in the specifications for a particular monitor, but such information is in the characteristics of the matrix used. To put it simply, this is the number of colors displayed. You can often find that a monitor displays 16.7 million colors. This is the most common value for this parameter. The problem is that this can be achieved in different ways.

Let me remind you that any color is formed from three basic ones - red, blue, green. Accordingly, the monitor matrix has a certain bit depth for each color, measured in bits. If there are 8 bits for each color, then we get 256 shades of each color, which in combination gives 16.7 million colors. Everything is fine, the monitor shows perfectly, you can take it.

What if each color is not encoded with 8 bits? Cheap displays often use 6-bit matrices, but in addition the abbreviation “+FRC” is also indicated. What do these letters mean?

First, you need to consider that with 6-bit color coding you can get 262 thousand colors. How do you get the final 16 million? This is precisely due to FRC (Frame Rate Control) technology.

The idea is to obtain the “missing” halftones by showing an intermediate frame with two other colors, which ultimately produce those shades that are not available for the 6-bit matrix. In fact, we have another flicker.

Is having FRC bad? Again, a lot depends on the tasks that are performed on the monitor and on the characteristics of vision. Some people don't notice FRC, while others find it annoying. And purely subjectively, if you have to work with color, then it would be better to have a monitor with an “honest” 8-bit matrix.

For professionals, monitors are available with a 10-bit matrix, which allows them to display more than a billion shades. I think there is no need to say that the cost of such monitors is not the smallest, and for office/home/gaming use an 8-bit monitor or even a 6-bit+FRC monitor is quite suitable if the flickering is not noticeable and high demands are not placed on the screen.

13. Screen refresh rate

Unlike old CRT monitors, this parameter is not so important for displays made using LCD technology, especially if everything is limited to office work, surfing the Internet, and watching videos. If the matrix produces 60-75 Hz, this is more than enough.

This option should be taken into account by those who play games, especially those with fast moving objects on the screen. It is also important which video card is used in this case. If it is capable of producing a large number of FPS, then it would be better if the screen refresh rate was higher.

If you look at display models, including those in gaming laptops, you will notice that screens with refresh rates of 120, 144 Hz or even higher are offered. In this case, fast movement on the screen will be smoother and with smaller trails trailing behind the moving objects.

Strictly speaking, in this case, not only the refresh rate, but also the speed of the matrix is ​​important. The pixels that make up the image must have time to change the glow parameters depending on the change in the displayed image. By the way, short response times combined with high refresh rates are real arguments in favor of the fact that TN technology is still relevant for gaming monitors.

It should also be mentioned that a high screen refresh rate is not bad, it allows you to reduce the severity of the problem of desynchronization of the frame rate produced by the video card and the image refresh rate on the monitor. This is relevant for games, and the following parameter helps solve this problem.

14. NVidia G-Sync and AMD FreeSync

First, let's briefly describe the problem. The ideal situation is when the video card generates and outputs each frame to the monitor at a frequency equal to the screen refresh rate. Unfortunately, at each moment in time the video chip has to calculate completely different scenes, some of which are “easier” and take less time to complete,” while others require significantly more time to render.

As a result, frames are delivered to the monitor at a rate higher or lower than the screen refresh rate. Moreover, if the video card has time to calculate, produce a frame, and even rest a little before rendering the next one while waiting for the next screen update cycle, then there are no special problems.

It’s another matter if the game has high graphics settings and the video processor has to strain all its silicon forces to calculate the scene. If the calculation takes a lot of time and the frame is not ready for the start of the update cycle, there are two possible scenarios:

• The cycle is skipped.
• Rendering begins when the frame is ready and presented to the monitor.

In the first case, you need to enable the V-Sync vertical synchronization mode. If a new frame is not prepared when the screen refresh begins, the previous one continues to be displayed. The result is the appearance of microdelays in the image, twitching. But the picture is complete.

If V-Sync mode is turned off, the movement will become smoother, but another problem may appear - if the frame is prepared somewhere inside the screen refresh cycle, then the frame will consist of two parts, old and new, which will begin to be drawn from the moment it is submitted to monitor. Visually, this is expressed in horizontal image breaks and steps.

A higher refresh rate reduces the problem. But it doesn’t completely solve it. NVidia G-Sync and AMD FreeSync technologies can help get rid of these unpleasant image problems.

As the name suggests, they are offered by video card manufacturers. Therefore, when choosing a monitor that has one of these technologies, you should consider which video card is in your computer, or which one you are going to install. It is unwise to buy a monitor with G-Sync for an AMD video card and vice versa. A waste of money on something that won't be used.

Now about these technologies themselves. Their operating principle is similar, but the solution methods differ. NVidia uses its own hardware and software method, i.e. the monitor has a special unit responsible for G-Sync, while AMD uses the DisplayPort Adaptive-Sync protocol, i.e. without installing additional hardware units in the monitor.

In this case, it does not matter by what means the problem is solved, what is important is what can be obtained in the end. In short, the principle of operation of G-Sync and its analogue from AMD is as follows.

The screen refresh rate is not fixed, but is tied to the rendering speed of the video card. The image appears on the monitor at the moment the frame is ready for display. As a result, we do not get fixed, for example, 60 Hz screen updates, but a floating value. One frame is calculated quickly - and it immediately appears on the screen. The second one takes longer to render - the display matrix waits and does not update the image until the frame is ready.

As a result, we have a smooth image without gaps or other artifacts. Thus, in the case of a monitor chosen for gaming, the ideal option is a model with one of these two technologies (taking into account the coincidence of the manufacturer of the video card in the computer) and, preferably, with a refresh rate of 120 Hz or higher. True, such a display will definitely not be cheap.

15. Interfaces

I won’t go into detail here, because I think it’s already clear. These are connectors installed in the monitor for connecting to the video card. For laptops, the parameter is generally irrelevant, since the display comes “included” and is connected initially.

Rest

I think that characteristics such as weight, size, type of power supply (built-in or remote), power consumption during operation and idle time, the presence of built-in speakers, the ability to mount on a wall, etc. are not something complicated and incomprehensible. That's why I won't describe them.

Conclusion. Monitor characteristics - which are more important, which are less important

I hope I didn’t miss anything important, and if I suddenly forgot to write about something, indicate it in the comments, I’ll add, expand, deepen. Based on the results of what has been said, it becomes clear that choosing a monitor is not only about solving issues related to the required diagonal, matrix type and resolution.

This may be enough for the office, but if the display is chosen for home use, for games, image processing or other specific tasks, then in order not to be disappointed in the purchase, you have to delve deeper into the characteristics of the monitor.

The matter is complicated by the fact that its own vision makes its own adjustments, which does not like, for example, the presence of flicker, imperfections of the matte coating, or the work of FRC being noticeable to the eye. And this cannot be ignored, because we only have eyes and we won’t get new ones.

There is one more “subtle” point - the initial settings of the monitor by the manufacturer. Just because he shows “something wrong” doesn’t mean he can’t show better. However, calibrating a monitor is a painstaking task, and sometimes requires special equipment. At a minimum, you can try to adjust the parameters “by eye”, try to get an image that you will like visually.

I myself recently bought a monitor, although I chose something inexpensive on IPS or VA, and gaming “bells and whistles” were not important to me. However, flicker-free performance was one of the main criteria.

Have a good shopping and let your eyes say “thank you” for the right monitor.

And knowledge of the subtleties in its choice will help you choose the right model correctly. We should start with their types. Today there are 3 types of monitors. CRT, LCD and LED.

To calculate the monitor diagonal, you can use the monitor diagonal calculator in inches and centimeters.

CRT or cathode ray tube is a long-obsolete technology used in monitors. CRT monitors are already an antiquity that has passed into retirement. Unless someone still has these “pot-bellied” monsters with a convex screen. Then, of course, they removed the belly and bulge and continued to produce CRTs, but with a flat screen.

LCD (liquid crystal display) - liquid crystal monitors, thin and flat, replaced electron beam ones. Most users have this type. This monitor uses fluorescent lamps. The image quality is better, power consumption is less.

LED (light-emitting diode) is a modern type of LCD monitor. The technology is based on light-emitting diodes. As a result, the colors are more saturated and the picture is of higher quality.

To calculate the TV diagonal, you can use the TV diagonal calculator in inches and centimeters.

Monitor size specifications.

This is the size, or more correctly, the diagonal of the screen, which is measured in inches and can have any value. In the days of CRT monitors, 17 inches was considered a good diagonal. With the advent of LCD, monitors began to increase in size and became wide-format, and the diagonal exceeded 20, and then 30 inches. Optimally, for desktop use you need 23-24 inches, but if your needs are larger, there are also huge screens of 27 or 32 inches. The larger the diagonal, the higher the resolution you can set.

Monitor resolution as its characteristic.

Resolution is the number of pixels (dots) horizontally and vertically. For example, in a resolution of 1024*768, the first number is the number of horizontal pixels, and the second number is vertical. As a rule, the higher the resolution, the better the quality of the image on the screen. Separately, it is worth highlighting such monitor characteristics as the screen aspect ratio. Initially, all monitors were in 4:3 format, that is, the screen was almost square. With the advent of wide screen monitors, formats such as 16:9 and 16:10 appeared. Of course, there are others, but these are considered the most common. The wide format allows you to contemplate the screen more comfortably, thanks to greater visibility and expanded space.

Monitor characteristics - matrix.

The last important image characteristic when choosing a monitor is its matrix, which is responsible for the behavior of liquid crystals and their role in image formation.

To calculate the laptop screen size, you can use the laptop screen size calculator in inches and centimeters.

It makes no sense to go into the details of each matrix, but 3 main types can be distinguished:

1. TN (TN+Film - Twisted Nematic). A cheap and outdated type, the downside of which was poor visibility of the picture from different angles.

2. IPS (In Plane Switch). This type is more expensive and has a longer response time compared to TN, but this is compensated by an excellent picture and no problems with viewing angles.

3. PVA/MVA (VA). This matrix appeared later and is something between the first two types. The price of such a matrix is ​​correspondingly cheaper than IPS.