Response time
Screen response time to a control signal — in other words, the time between the receipt of such a signal on the matrix and the switching of pixels to a given mode.
Theoretically, the lower the response time, the better the screen handles with dynamic scenes, the higher the frame rate on it can be achieved. At the same time, it is worth noting that almost all modern matrices have sufficient response speed to effectively process the classic frame rate of 60 Hz — and, recall, it is quite enough for most cases. So paying attention to this parameter makes sense, first of all, if you are purchasing an advanced gaming model, the screen of which operates at a frame rate of more than 60 Hz. In other cases, the response time is often not indicated at all.
Refresh rate
The frame rate supported by the laptop screen. In fact, in this case we are talking about the maximum frequency; the actual frame rate may be lower than this value, depending on the content being displayed — but not higher.
Theoretically, the higher the frame rate, the smoother the movement on the screen will look, the less moving objects will be blurred. In fact, the situation is such that even in relatively modest modern laptops,
60 Hz matrices are installed — in general, this is quite enough for the human eye, since a further increase in speed (
90 Hz and higher) does not significantly improve the visible “picture”. However, in high-end gaming and multimedia models designed for demanding users, higher values —
120 Hz,
144 Hz,
165 Hz and even
higher, namely
240 Hz and
300 Hz.
Brightness
The maximum brightness that a laptop screen can provide.
The brighter the ambient light, the brighter the laptop screen should be, otherwise the image on it may be difficult to read. And vice versa: in dim ambient light, high brightness is unnecessary — it greatly burdens the eyes (however, in this case, modern laptops provide brightness control). Thus, the higher this indicator, the more versatile the screen is, the wider the range of conditions in which it can be effectively used. The downside of these benefits is an increase in price and energy consumption.
As for specific values, many modern laptops have a brightness of
250 – 300 nt and even
lower. This is quite enough for working under artificial lighting of medium intensity, but in bright natural light, visibility may already be a problem. For use in sunny weather (especially outdoors), it is desirable to have a brightness margin of at least
300 – 350 nt. And in the most advanced models, this parameter can be
350 – 400 nt and even
more.
Contrast
The contrast of the screen installed in the laptop.
Contrast is the largest difference in brightness between the lightest white and darkest black that can be achieved on a single screen. It is written as a fraction, for example, 560:1; while the larger the first number, the higher the contrast, the more advanced the screen is and the better the image quality can be achieved on it. This is especially noticeable with large differences in brightness within a single frame: with low contrast, individual details located in the darkest or brightest parts of the picture may be lost, increasing the contrast allows you to eliminate this phenomenon to a certain extent. The flip side of these benefits is an increase in cost.
Separately, we emphasize that in this case only static contrast is indicated — the difference provided within one frame in normal operation, at constant brightness and without the use of special technologies. For advertising purposes, some manufacturers may also provide data on the so-called dynamic contrast — it can be measured in very impressive numbers (seven-digit or more). However, you should focus primarily on static contrast — this is the basic characteristic of any display.
As for specific values, even in the most advanced screens, this indicator does not exceed 2000: 1. But in general, modern laptops have a rather low contrast ratio — it is assumed that for tasks that require more advanced image characteristics, it is more...reasonable to use an external screen (monitor or TV).
Colour gamut (Adobe RGB)
The colour gamut of the laptop matrix according to the Adobe RGB colour model.
Colour gamut describes the range of colours that can be displayed on the screen. It is indicated as a percentage, but not relative to the entire variety of visible colours, but relative to the conditional colour space (colour model). This is due to the fact that no modern screen is able to display all the colours visible to humans. However, the larger the colour gamut, the wider the screen's capabilities, the better its colour reproduction.
The Adobe RGB colour model was originally developed for print applications; the range of colours covered by it corresponds to the capabilities of professional printing equipment. Therefore, theoretically, the extensive coverage of this model will be useful to those involved in the design and layout of high-end printed products. However most laptop screens have very limited Adobe RGB values, rarely exceeding 74%; however, you can also find high-end models where this figure
approaches 100%. Of course, the cost of such laptops will also be appropriate; therefore, it makes sense to pay attention to them, first of all, when the ability to work with colour “on the go” is of key importance. If this is to be done in one place, it may be more justified to buy a separate monitor with a wide colour gamut (especially since a monitor with such characteristics is easier to find than a laptop).
TÜV Rheinland certificate
Laptop display certification for safe blue light emission levels and panel flicker rates.
The presence of a TÜV Rheinland certificate confirms that the screen is comfortable for the eyes.
TÜV Rheinland is a large international concern headquartered in Cologne, Germany, providing a wide range of audit services. The company's specialists have developed and approved a number of tests for the compliance of the screens of mobile devices, monitors and TVs with the required level of eye protection from the harmful effects of display radiation on the user's vision on the other side of the screen. The authoritative opinion of TÜV Rheinland is respected in the tech community. Certificates from this body are issued to successfully tested electronics for the implementation of blue light filtering and screen flicker suppression technologies.
HDR
HDR technology format supported by the laptop.
This technology is designed to expand the range of brightness reproduced by the laptop screen; Simply put, an HDR screen will display brighter whites and darker blacks than a regular matrix. In fact, this can significantly improve image quality. First, the expansion of the dynamic range contributes to the brightness and fidelity of colours on the screen; secondly, the visibility of individual details in very bright or very dark areas of the frame is preserved (whereas on a normal screen such details often “sink” in solid white or black).
Note that in order to fully use this function, you need not only
a laptop with HDR, but also the corresponding content (video files recorded in HDR, games where this technology is implemented, etc.). In addition, the laptop must support the HDR format used by the content being played. Nowadays, you can find such options:
— HDR10. Historically the first of the consumer HDR formats, less advanced than those described below, but extremely widespread. In particular, HDR10 is supported by almost all streaming services that provide HDR content at all, and it is also common for Blu-ray discs. Allows you to work with a colour depth of 10 bits (hence the name). At the same time, devices of this format are also compatible with content in HDR10 +, although its quality will be limited by the capabilities of the original HDR10.
...— HDR10+. An improved version of HDR10. With the same colour depth (10 bits), it uses the so-called dynamic metadata, which allows transmitting information about the colour depth not only for groups of several frames, but also for individual frames. This results in an additional improvement in colour reproduction.
Dolby Vision. An advanced standard used particularly in professional cinematography. Allows you to achieve a colour depth of 12 bits, uses the dynamic metadata described above, and also makes it possible to transmit two image options at once in one video stream — HDR and normal (SDR). At the same time, Dolby Vision is based on the same technology as HDR10, so in laptops it is almost guaranteed to be combined with at least HDR10, and even with HDR10 +.VESA DisplayHDR Certification
VESA DisplayHDR certified, which corresponds to a screen that supports HDR technology.
See above for more details on this technology. And VESA DisplayHDR is an open standard that defines the overall image quality on an HDR screen by a number of parameters — brightness, colour depth, etc. Based on the test results, a screen that meets the required parameters is assigned a certain certificate with a numerical designation. So, the minimum level is DisplayHDR 400, the maximum is DisplayHDR 1400 (although in laptops, as of the end of 2020, there are no screens higher than DisplayHDR 1000). The number in such a designation is indicated by the brightness that the screen must provide: for example, DisplayHDR 400 must produce at least 400 cd / m2. Accordingly, a higher number denotes more extensive display capabilities and more advanced HDR performance.
A separate case is the DisplayHDR True Black certifications. This standard was specifically created for so-called emissive displays such as OLED (see "Matrix type"), which are capable of displaying very deep blacks. The native brightness of such displays is not very high — in particular, the current DisplayHDR 400 True Black and DisplayHDR 500 True Black provide a total screen brightness of only 250 and 300 cd / m2, respectively (against 400 and 500 cd / m2 in the original standards, without the addition " True Black"). However, in terms of black transmission efficiency, such di
...splays surpass conventional HDR counterparts by orders of magnitude, which gives a noticeable increase in image quality — in particular, the mentioned True Black standards with indexes 400 and 500 win even when compared with conventional DisplayHDR 1000. However, it should be taken into account that that this advantage is most noticeable in relatively dim ambient light. AMD compatibility
The laptop supports
AMD FreeSync technology and its more advanced varieties (FreeSync Premium, FreeSync Premium Pro). Here are more details about them:
– AMD FreeSync. This function is found only in models equipped with discrete AMD graphics cards. It serves to match the frame rate of the screen and the frame rate of the incoming signal so that the frequencies match. This allows you to avoid flickering, jerking and other image defects that occur due to signal desynchronization. This function is especially useful for games where the frame rate of the video signal can “float” depending on the load on the graphics core; in fact, most laptops with FreeSync are specifically gaming laptops.
– AMD FreeSync Premium. An intermediate option between the core AMD FreeSync technology and the advanced FreeSync Premium Pro implementation. The Premium version does not have HDR support (unlike Pro), but it works at the same frame rate (at least 120 fps at a resolution of 1920x1080) and uses LFC low frame rate compensation technology.
– FreeSync Premium Pro. The most advanced version of FreeSync technology, formerly known as AMD FreeSync 2 HDR. As the original name suggests, one of the highlights of this edition is HDR support. FreeSync Premium Pro claims a frame rate of at least 120 fps at Full HD resolution, as well as a low frame rate compensation (LFC) function. According to the creators, FreeSync Premium Pro works espec
...ially well in games; and many modern games are initially created to work with this technology.
NVIDIA video cards use a similar technology called G-Sync.