Comparison Dell U2718Q 27 " black vs Dell P2715Q 27 "

The technology by which the monitor matrix is made.

— TN+film. The oldest and most common technology for manufacturing matrices. The original TN (Twisted Nematic) monitors have a low response time and low cost, but the image quality is average. So, the colour quality is not high, and the perfect black colour cannot be reproduced at all. In addition, the original TN technology provides relatively small viewing angles. To correct this situation, a special film is applied to the surface of the matrix. These matrices received the name "TN + film". Monitors with such a matrix are widespread and inexpensive. They are well suited for undemanding users both at home and in the office, and gamers will appreciate the fast response time.

— *VA(Vertical Alignment, options: MVA, PVA, Super MVA, Super PVA). A kind of transitional option between expensive and high-quality IPS and low-cost TN. Provide sufficiently high-quality colour reproduction, including black colour, viewing angles can reach 178°. The main disadvantage of VA matrices is the significant response time (especially for MVA monitors), due to which such monitors are relatively poorly suited for watching videos and dynamic games. This shortcoming is gradually being eliminated, and the latest models of VA monitors are approaching TN + film in respo...nse time.

— IPS. Initially, IPS technology was created for high-end monitors (in particular, "designer"), the key parameters for which were the quality of colour reproduction and a wide colour gamut. With all these advantages, the original IPS matrices also had a number of serious drawbacks — first of all, low response speed and impressive cost. Thus, many modifications of the IPS technology have been developed, designed to compensate for these shortcomings to one degree or another.

— OLED. Monitors with screens using organic light emitting diodes — OLED. Such LEDs can be used both to illuminate a traditional matrix, and as elements from which a screen is built. In the first case, the advantages of OLED over traditional LED backlighting are compactness, extremely low power consumption, backlight uniformity, as well as excellent brightness and contrast ratios. And in matrices, consisting entirely of OLED, these advantages are even more pronounced. The main disadvantages of OLED monitors are the high price (which, however, is constantly decreasing as the technology develops and improves), as well as the susceptibility of organic pixels to burn-in when broadcasting static images for a long time or pictures with static elements (toolbar, clock, etc.).

— QLED. Monitors built using quantum dot technology (QLED). This technology can be used in matrices of various types. It involves replacing a set of several colour filters used in classic matrices with a special thin-film coating based on nanoparticles, and traditional white LEDs with blue ones. This allows you to achieve higher brightness, colour saturation and colour quality at the same time as reducing the thickness and reducing power consumption. In addition, QLED is well suited for creating curved screens. The flip side of these benefits is the high price.

— QD-OLED. A kind of hybrid version of matrices that combine “quantum dots” (Quantum Dot) and organic light-emitting diodes (OLED) in one bottle. The technology takes the best from QLED and OLED: it is based on blue LEDs, self-luminous pixels (instead of external backlighting) and “quantum dots”, which play the role of color filters, but at the same time practically do not attenuate the light (unlike traditional filters) . Thanks to the use of a number of advanced solutions, the creators managed to achieve very impressive characteristics, significantly superior to many other OLED matrices. Among them are high peak brightness from 1000 nits (cd/m²), excellent contrast and black depth, as well as an expanded color gamut (over 120% of the DCI P3 gamut). Such matrices are found mainly in expensive advanced monitors with a large screen diagonal.

— AHVA. A type of matrix created by AU Optronics (a joint venture between Acer and BenQ) as a solution similar to modern IPS. Among the key advantages of this option over analogues is the almost complete absence of colour distortions at all viewing angles.

– PLS (Plane to Line Switching). This type of matrix was developed by Samsung engineers. It is based on the familiar IPS technology. According to some parameters, namely: the brightness and contrast of PLS exceeds IPS by 10%. The main goal of creating a new type of screens was to reduce the cost of the matrix, according to the developer, the production cost was reduced by 15%, which will positively affect the final price of monitors in comparison with IPS counterparts.

— IGZO. Technology introduced by Sharp in 2012. The key difference between IGZO and classic LCD matrices is that for the active layer (responsible for creating the image) it uses not amorphous silicon, but a semiconductor material based on indium gallium oxide and zinc oxide. This makes it possible to create screens with extremely fast response times and high pixel densities, and the technology is considered well suited for ultra-high resolution screens. With all this, the colour rendering characteristics allow the use of IGZO monitors even in the professional field, and the power consumption is very low. The main disadvantage of this option is the high cost.

— UV2A. An LCD display technology developed by Sharp and introduced in 2009. One of the key features of UV2A matrices is that they are based on liquid crystals that are sensitive to ultraviolet light. And it is UV radiation that is used as a control signal — it ensures that the crystals turn in the right direction to form an image. The technical features of such systems are such that the position of individual crystals can be controlled with extremely high accuracy — up to several picometers (with the size of the crystals themselves about 2 nm). According to the manufacturer, this provides two key benefits: no backlight "leakage" and improved light transmission with "open" crystals. The first allows you to achieve very deep and rich blacks, the second provides excellent brightness with low power consumption, and together these two features make it possible to create screens with a very high static contrast ratio — up to 5000: 1. At the same time, we note that the actual contrast characteristics in UV2A monitors can be noticeably more modest — it all depends on the features of a particular matrix and the characteristics that the manufacturer was able or considered necessary to provide.

— Mini LED IPS. A variation on the theme of the familiar IPS-matrix, which is illuminated by an array of reduced LEDs. The small caliber of individual light sources (of the order of 100-200 microns) makes it possible to form a much larger number of zones of controlled local dimming of the screen. Together, this delivers improved brightness, contrast, colour saturation, and black depth, and raises the bar for High Dynamic Range (HDR) technology.

— Mini LED VA. A variety of VA-matrices with a Mini LED backlight system. It consists of many tiny LEDs, which, due to their number, form many times more local screen dimming zones than standard canvases. As a result, Mini LED VA panels boast improved colour reproduction, impressive black depth, and multiple performance improvements in HDR content.

— Mini LED QLED. Behind the plane of the QLED panel in monitors with a Mini LED backlight system are thousands of miniature LEDs no larger than 200 microns in size, which divide the screen into a great many zones with controlled local dimming. They are individually dimmable, allowing full display of HDR content with bright light and deepest black levels.

Modern monitors can use displays with both glossy and matte screen surfaces. A matte surface is in some cases more preferable due to the fact that on a glossy screen, when exposed to bright light, noticeable glare appears, sometimes interfering with viewing. On the other hand, glossy screens offer better picture quality, higher brightness, and richer colours.
Due to the development of technology, monitors with a special anti-glare coating have appeared on the market, which, while maintaining all the advantages of a glossy screen, creates significantly less visible glare in bright ambient light.

The size of one dot (pixel) on a monitor screen. This parameter is related to the maximum resolution of the monitor and its diagonal size — the higher the resolution, the smaller the pixel size (with the same diagonal) and vice versa, the larger the diagonal, the larger the size of one pixel (with the same resolution). The smaller the size of one pixel, the clearer the image will be displayed by the monitor, the less grainy it will be noticeable, which is especially important on large monitors. On the other hand, a small pixel size creates discomfort when working with fine details and text — this mainly applies to monitors with a small diagonal.

The time spent by each individual point on the monitor to switch from one state to another. The shorter the response time, the faster the sensor responds to the control signal, the lower the delay and the better the image quality in dynamic scenes.

Note that in this case, the grey-to-grey method is used (the turn-on time is from 10% grey to 90%). It is worth paying attention to this parameter if the monitor is specially purchased for dynamic games, watching movies and other applications associated with fast movement on the screen. And even in such cases, a reaction speed of 8 ms is quite enough; a further decrease in response time does not affect the quality of the perceived image.

Static contrast provided by the monitor screen.

This value describes the difference between the brightest whites and darkest blacks that the screen is capable of producing. In this case, unlike dynamic contrast (see below), the difference is indicated on the condition that the brightness of the screen backlight remains unchanged. In other words, this is the contrast that is guaranteed to be achievable within one frame. Static contrast is inevitably lower than dynamic. However, it is she who describes the basic capabilities of the screen.

The minimum static contrast ratio for tolerable image quality is considered to be 250:1, but even the most modest modern monitors give out about 400:1 (and a value of 1000:1 is not the highest class), and in high-end models this figure can reach 2000:1 and even more. .

Dynamic contrast provided by the monitor screen.

Dynamic contrast refers to the difference between the brightest white at maximum backlight intensity and the deepest black at minimum backlight. In this way, this indicator differs from static contrast, which is indicated with a constant backlight level (see above). Dynamic contrast ratio can be expressed in very impressive numbers (in some models — more than 100,000,000: 1). However, in fact, these figures are poorly correlated with what the viewer sees: it is almost impossible to achieve such a difference within one frame. Therefore, dynamic contrast is most often more of an advertising than a practically significant indicator, it is often indicated precisely in order to impress an inexperienced buyer. At the same time, we note that there are "smart" backlight technologies that allow you to change its brightness in certain areas of the screen and achieve a higher contrast in one frame than the claimed static one; these technologies are found mostly in premium monitors.

The colour gamut of a monitor characterizes the range of colours that the screen is capable of reproducing.

This parameter is specified as a percentage, however, 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. Monitor specifications may specify which colour model is used for gamut (see below). If there is no such clarification, then, usually, we are talking about the sRGB model — it is accepted as a general standard for computer technology. In this case, the closer the colour gamut of the monitor is to 100%, the more accurately the colours on the screen will match the colours that were originally intended. Too little colour gamut results in a dull, faded image, and too much — unnatural and oversaturated. However, in fact, values from 90% to 110% are considered quite acceptable for most cases and do not lead to a noticeable deterioration in the image. In general, it is considered that “more is better than less”, and for a high-end monitor (especially professional) sRGB coverage should be 100% or higher.

Monitor colour gamut Rec. 709 or sRGB.

Any colour gamut is indicated as a percentage, however, 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 monitor's capabilities, the better its colour reproduction.

Nowadays, sRGB is actually the standard color model adopted for computer technology; This is what is used in the development and production of most video cards. For television, the Rec. standard, similar in parameters, is used. 709. In terms of the range of colors, these models are identical, and the percentage of coverage for them is the same. In the most advanced monitors it can reach or even exceed 100%; These are the values that are considered necessary for high-end screens, incl. professional.

This technology is designed to expand the range of brightness reproduced by the monitor; Simply put, an HDR model will display brighter whites and darker blacks than a "regular" display. In fact, this means a significant improvement in colour quality. On the one hand, HDR provides a very "live" image, close to what the human eye sees, with an abundance of shades and tones that a normal screen cannot convey; on the other hand, this technology allows to achieve very bright and rich colours.

Modern HDR monitors may use the DisplayHDR designation. This standard takes into account a number of parameters that determine the overall quality of HDR performance: brightness, colour gamut, colour depth, etc. Based on the results of measurements, the monitor is assigned one of the following markings: DisplayHDR 400 means relatively modest HDR capabilities, DisplayHDR 600 is average, DisplayHDR 1000 is above average, DisplayHDR 1400 is advanced. At the same time, the absence of a DisplayHDR label in itself does not mean anything: it’s just that not every HDR monitor is tested according to this standard.

Note that for the full use of HDR, you need not only the appropriate monitor, but also content (movies, television, etc.) originally created in HDR. In addition, there are several different HDR techn...ologies that are not compatible with each other. Therefore, when buying a monitor with this function, it is highly desirable to clarify which version it supports.