Screens and resolutions

The transition to high-density pixel displays that began with smartphones and tablets has spread to the computer monitors. 4K PC screens appeared in 2014, and understanding pixel density has become important when choosing a product, along with screen size and resolution. Our topic is the transition to high pixel density screens, including trends in the latest technology. There are two standards for 4K resolution, “DCI 4K” and “UHD 4K”.
DPI (dots per inch) is the number of dots located within a 1-inch scan or print line. For monitors and displays, DPI is discarded in favor of PPI (pixels per inch). Although PPI is an accurate term for monitors and other displays, the two terms are often used interchangeably.

High-density monitors or Retina monitors sold by Apple are generally recognized as having a physical pixel density greater than 200 pixels per inch (PPI). This means that they have twice the pixel density of a high-resolution computer monitor. Smartphones and tablets are the main drivers for this trend due to their low cost and high pixel density, which is usually higher than 250 PPI. This means that the average person cannot see individual pixels on a high-density screen, 10-15 inches away on a smartphone or tablet, or 20+ inches on a laptop or computer screen.

The number of device pixels that make up a CSS pixel in one direction is its Device Pixel Ratio (DPR). You can interpret this as the width (or height) of the grid of device pixels that fit inside one CSS pixel. Every device has a different DPR. Higher resolution devices have a higher DPR. These devices can see sharper images because they devote more screen pixels to each CSS pixels. This means nuances in the image are better represented.If a Web browser (or any other application for that matter) naively continues to say that one pixel according to the app’s concept of pixels is the same as one pixel on the screen, then eventually you have text and images so small that they’re impossible to view easily.

The reason that CSS pixel ratio was created is because as phones screens get higher resolutions, if every device still had a CSS pixel ratio of 1 then webpages would render too small to see.
4K monitors for PCs hit the shelves in 2014, and understanding pixel density has become important when choosing products along with screen size and resolution. It is predicted that 4K will replace Full HD as the standard resolution. Of course, 4K stands for 4,000 and refers to a horizontal number of pixels around this number.

DCI 4K has twice the screen resolution of 2048 x 1080 pixels on projectors (4096 x 2160 / approx. 17: 9) and is the 4K industry's 4K resolution. UHD 4K (also called UHDTV 4K), on the other hand, is the 4K resolution of the television industry, which was defined by the International Telecommunication Union (ITU). It has twice the horizontal resolution of 1920 x 1080 pixels Full HD (3840 x 2160/16: 9).
Since the second half of the 2000s, square screens with 5: 4 and 4: 3 image formats have been in decline in the PC screen market, while 16: 9 and 16:10 widescreen screens are on the rise and becoming too established. At the same time, there was a shift from square 17 "and 19" screens to 23 "and 24" widescreen screens. There is also an active trend for 27 "or larger widescreen displays for even more comfortable environments. This transition is split between those looking for a larger workspace, 3840 x 2160 pixels (UHD 4K) or 2560 x 1440 Pixel select ( WQHD), and those looking for a screen with better visibility at a lower price, choose 1920 x 1080 pixels (Full HD). In recent years, ultra-wide screen products with even wider screens have also hit the shelves. These are super wide screen products with a 21: 9 aspect ratio.

Moreover, the world of 8K, which follows 4K and 5K, is almost there. 8K (7680 x 4320 pixels / 16: 9) compatible screen test models have appeared at video shows and events, and the transition to higher resolution and higher resolution will continue at a rapid pace. Looking at stand-alone monitors, a hot topic lately has been super high pixel density 4K high-resolution pixel monitors packed in 24- to 27-inch screen sizes. Originally, this genre only attracted the attention of some top consumers, but cheap products began to appear on the shelves one after another in 2014, so the number of regular users showing interest increased.
Computer monitors are designed based on the assumption that OS and applications will have a fixed screen density (96 ppi for Windows). The 96 dpi standard is behind this assumption, and the screen size increased with the higher resolution of the LCD panel (increased number of pixels), so it was safe to just consider that the higher the resolution (number of pixels), the larger the working area.

PPI stands for "pixels per inch" (not per square inch). One inch is 2.54 centimeters. If you reduce the pixel height without changing the screen size of the LCD screen, the ppi will increase and the higher this value, the higher the screen resolution. For example, at 100 ppi it has 100 pixels of 2.54 centimeters each, and at 300 ppi 300 pixels are packed to the same width.For most purposes, pixels and dots and ppi and dpi are interchangeable concepts. However, it is useful to separate them when calculating how many pixels will be needed to print an image of a certain size with a printer at a given dpi resolution.

Although theoretically a higher PPI is always better, before making any purchase, you should also know that most people's eyes probably cannot detect any difference in a PPI that exceeds a certain limit.

When choosing an LCD in the future, one must also consider the pixel density, which results from the combination of screen size and resolution. As already mentioned, displays with a super high pixel density basically require an enlargement with scaling for use, so that a high resolution (high number of pixels) does not equal a large working space. This is an important point that needs to be carefully considered.

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