Among the key technical characteristics of computer displays and television monitors is the refresh rate. In what cases is this parameter allowed? When is it desirable to adjust manually? In what situations does this procedure not make sense?
What is screen frequency?
A computer monitor or TV screen works on the basis of the sequence of frames. That is, something like a movie projector. The frame rate during movie reproduction is about 25-30. In the case of a PC monitor or TV screen, this figure should be higher, since the built-in picture is much more complicated than the video sequence on the film. General rule - the higher the frequency indicator, the sharper the image and the more pleasant it is to look at the screen.
Screen frequency and type
There are several technological types of screens and monitors. The most modern are LCD, LCD and LED. Relatively outdated are considered CRT. The refresh rate of the LCD TV screen or monitor (using the same technology) is determined taking into account other principles than in the case of devices in which electron beam projectors are installed. In the case of the LCD display, the picture is drawn across the entire screen immediately.
If we are talking about CRT displays - line by line. Therefore, if the refresh rate of the LCD TV screen and the cathode-ray unit is the same, then the quality will most likely differ in favor of the first type of device. Moreover, if the corresponding indicator is about 60 Hz (the number of display updates per second), then in the case of CRT monitors, flicker will be very noticeable.
Frequency setting for CRT displays
Therefore, we will pay special attention to setting up cathode ray displays. How to change the CRT-type screen refresh rate in Windows using XP as an example? Very simple. You must enter the "Control Panel". Then select "Screen". Having opened the corresponding window, it is necessary to find the tab “Parameters”. Further - "Advanced". There will most likely be a list of several options.
What screen refresh rate should I set? For CRT monitors, the recommended value is 85 Hz. If this figure is not in the list, then this is most likely due to the fact that the factory driver for the video card is not installed on the PC. It must be downloaded on the Internet or searched on the disks that were attached to the PC at the time of sale. You can also try contacting a service center asking for help with the driver.
CRT displays: nuances
Note that in almost all operating systems it is possible to change such a parameter as the screen refresh rate. Windows 7 as the most modern and, it would seem, does not require significant intervention in the settings by the user, is no exception. In this version of the OS, the algorithm for setting the necessary parameters is almost the same. Through the "Control Panel" sets the desired refresh rate. What is the best operating system adapted to the appropriate settings? Almost all versions of Windows do the same. True, with regard to the latest versions of the OS (the same Windows 7), they may have some difficulties with drivers for legacy devices. But they are solvable - as a rule, any software of the appropriate type can be found on the Internet.
Also, when working in Windows 7, the algorithm for reaching the desired settings is slightly different from the script in XP. You need to enter the "Control Panel", then click on "Screen", after - select the change in its parameters. Then - "Advanced Settings". Next, go to the "Monitor" tab, where we find the frequency settings.
We also note that when setting all versions of the corresponding parameters in Windows, do not uncheck the box next to "Hide modes that the monitor does not use." The fact is that technologically the screen, of course, is able to work with settings outside the recommended ones. But in practice, this can create problems with the stability of the PC. Therefore, if the user asks how to change the refresh rate of the screen, if there is no necessary parameter, and the available values are lower than desirable for CRT screens, the first thing we recommend to him is to install the latest drivers on the video card.
Resolution factor
In some cases, the image quality on the CRT display depends on the resolution. At its higher values, simply more elements are placed on the screen. And in the case, for example, with photos or videos, it is possible to view them in more detail. The optimal resolution settings depend primarily on the size of the screen in inches. But, in principle, the user can experiment with setting different values. Note that you can change the resolution using the same algorithm as when changing the screen frequency - through the "Control Panel" and "Screen".
Note also that with too high a resolution, setting 85 HZ does not always work. And this, by the way, is one of the possible reasons why the desired figure may not be in the list of frequencies. Therefore, if the drivers are the latest, and 85 HZ is not listed, you can try to slightly reduce the resolution of the monitor.
LCD Frequency
It should be noted that the refresh rate of the picture on the LCD screen is in most cases a parameter that does not have much significance. Just because more or less modern monitors are factory-set so that frequency adjustment is simply not required. Even if it is equal to 60 Hz, which may be critical for CRT displays, the image will not noticeably flicker due to the technological specifics that we mentioned above. At the same time, with regard to LCD displays, another parameter is more important for them - pixel refresh rate. In many cases, it, by the way, is identified with the "frequency" of the screen - even among IT-specialists. This, strictly speaking, is not entirely true. If only because the pixel refresh rate is expressed not in hertz, but in another unit - milliseconds. But if this term is used in the context of "frequency", no one will probably accuse us of a lack of technical literacy. Therefore, when we use the term “frequency” in relation to LCD displays, we will understand it as “pixel refresh rate”.
So what is the best screen refresh rate in LCD monitors? The most important thing is to ensure optimal compliance of this parameter with the frame stream generated by the computer video card. That is, if, for example, this microcircuit produces a picture with a frequency of 60 hertz, and the LCD monitor does not have sufficient pixel refresh rate (this can be considered an indicator of about 30-40 milliseconds), then the image on the screen will seem to be "floating" . The smaller the corresponding parameter on the display, the better. Ideally, if it does not exceed 15 milliseconds. As a rule, the question of how to increase the refresh rate of an LCD-type screen is not worth it. In turn, the pixel refresh rate is a factory setting in most cases. Change it at home is problematic. Therefore, you should pay attention to it directly when buying a screen.
Technological aspect
Almost similar patterns are also characteristic of other digital devices that use an LCD display. That is, for example, the refresh rate of the laptop screen - the parameter is as "closed" for adjustment, as in the case of monitors for PCs.
The possible difference in image quality on the liquid crystal display in extremely rare cases depends on the set frequency values. Almost always, the key factor is the level of technology, which predetermines mainly the pixel refresh rate. Less important is what screen refresh rate is set. What is the best technology for constructing a picture in terms of "pixelation" and color rendition for a particular monitor model is determined primarily by the manufacturer. Screens of obsolete types, of course, can "give out" a not quite high-quality image. But as for modern products, significant problems with them, as a rule, do not arise. Also note that in addition to the "frequency" factor, a large number of other parameters specific to PC and laptop screens affect the picture quality. This is the resolution, type of matrix, characteristics of the video card.
LCD Screen Frequency
What are the features of LCD displays on LCD TVs? As for the key patterns - they are, in principle, the same as on computer screens. That is, on most modern television displays, the refresh rate is sufficient so that the image does not "jump". As for the pixel refresh rate - as a rule, TV manufacturers are trying to optimize everything for the characteristics of the screen. Therefore, special problems associated with the "floating" picture on modern TVs are not observed.
However, the refresh rate of the TV screen is a parameter characterized by a number of features. Which, for example? Once again, we note some duality in the use of technical terms. The fact is that there is as such a refresh rate of the screen image - the same principles apply to it as for the corresponding types of computer monitors. There is, in turn, another parameter, the frame rate of the video sequence, which is typical for televisions.
Regarding the second characteristic - you can draw a direct analogy with the film. This parameter characterizes how many frames per second pass through the screen space. In most modern LCD TVs, it is 50 Hz. Obviously, this is more than enough for the production of films - there the frame rate, as we said above, is usually within 30 units per second.
Thus, the refresh rate of the TV screen is an important parameter, but, as in the case of computers, additional adjustment, as a rule, does not require and is not subject to it by default. Similarly - with the frame rate of the video. This parameter is also typical factory.
TV: matrix specifications
It can also be noted that the technical characteristics of the TV include a number of additional parameters. Such as, for example, the response time of the matrix. How do LCDs work? An electric pulse is incident on the crystal, which is the “grain” of the overall picture on the display, as a result of which the pixel glows. However, due to technological features, it does not go out immediately. And therefore, on the screen, even after a new frame is displayed on it, the previous picture, which has not had time to disappear, may remain for a split second. As a result of this, an image, just as it happens on PC screens, may appear to be floating. But it is worth noting that modern models of LCD TVs are usually equipped with hardware components that can correct this display behavior. In addition, the response of the matrix on the TV screens that are currently being released is usually minimal. That is, in the case of LCD TVs, the question of how to increase the refresh rate of the screen is practically not worth it. Actually, in most cases TV owners do not have the ability to adjust the corresponding parameter.
PC and TV display frequency: conclusions
So, we learned what the screen refresh rate is, which is better for CRT monitors, in which the corresponding parameter in some cases requires manual adjustment in the Windows settings. What conclusions can we draw regarding the studied features of displays of various types?
The equivalent refresh rate of the screen in the CRT monitor and LCD means virtually nothing in terms of image quality comparison. If only because the principles of building a picture in each case are different. The second reason is that on liquid crystal displays, the frequency is rather a secondary factor in image quality. More important is another parameter - pixel refresh rate.
The picture quality, both in the case of LCD computer screens and relative to CRT displays, is largely determined by the characteristics of the video card. Moreover, it often happens that the corresponding type of chip is technologically behind the monitor. That is, for example, the display has a minimum indicator of the pixel refresh rate, and the video card cannot fully utilize this resource. In practice, this can be expressed in the fact that when starting computer games with a high frequency of the video sequence, some elements of the picture will not be clearly drawn. Although, again, we note - this kind of problem is quite rare today. As for films, there can be no objective reasons why the quality of a video sequence during their reproduction depends on the frequency (and in most cases, the speed of updating pixels), simply because films are usually a video stream up to 30 frames. Similarly - with LCD TVs, especially in modern versions. They set the optimal refresh rate for the screen. What is the best model to cope with the optimal reproduction of the footage - the question is, when answered, it is legitimate to pay attention, first of all, to the level of technology used by the brand. Frequency is a secondary aspect in this case.