Display resolution

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This chart shows the most common display resolutions, with the color of each resolution type indicating the display ratio (e.g. red indicates a 4:3 ratio).

The display resolution or display modes of a digital television, computer monitor or display device is the number of distinct pixels in each dimension that can be displayed. It can be an ambiguous term especially as the displayed resolution is controlled by different factors in cathode ray tube (CRT) displays, flat-panel displays (including liquid-crystal displays) and projection displays using fixed picture-element (pixel) arrays.

Contents

It is usually quoted as width × height, with the units in pixels: for example, 1024 × 768 means the width is 1024 pixels and the height is 768 pixels. This example would normally be spoken as "ten twenty-four by seven sixty-eight" or "ten twenty-four by seven six eight".

One use of the term display resolution applies to fixed-pixel-array displays such as plasma display panels (PDP), liquid-crystal displays (LCD), Digital Light Processing (DLP) projectors, OLED displays, and similar technologies, and is simply the physical number of columns and rows of pixels creating the display (e.g. 1920 × 1080). A consequence of having a fixed-grid display is that, for multi-format video inputs, all displays need a "scaling engine" (a digital video processor that includes a memory array) to match the incoming picture format to the display.

For device displays such as phones, tablets, monitors and televisions, the use of the term display resolution as defined above is a misnomer, though common. The term display resolution is usually used to mean pixel dimensions, the maximum number of pixels in each dimension (e.g. 1920 × 1080), which does not tell anything about the pixel density of the display on which the image is actually formed: resolution properly refers to the pixel density, the number of pixels per unit distance or area, not the total number of pixels. In digital measurement, the display resolution would be given in pixels per inch (PPI). In analog measurement, if the screen is 10 inches high, then the horizontal resolution is measured across a square 10 inches wide. [1] For television standards, this is typically stated as "lines horizontal resolution, per picture height"; [2] for example, analog NTSC TVs can typically display about 340 lines of "per picture height" horizontal resolution from over-the-air sources, which is equivalent to about 440 total lines of actual picture information from left edge to right edge. [2]

Background

1080p progressive scan HDTV, which uses a 16:9 ratio Progressive scan hdtv.svg
1080p progressive scan HDTV, which uses a 16:9 ratio

Some commentators also use display resolution to indicate a range of input formats that the display's input electronics will accept and often include formats greater than the screen's native grid size even though they have to be down-scaled to match the screen's parameters (e.g. accepting a 1920 × 1080 input on a display with a native 1366 × 768 pixel array). In the case of television inputs, many manufacturers will take the input and zoom it out to "overscan" the display by as much as 5% so input resolution is not necessarily display resolution.

The eye's perception of display resolution can be affected by a number of factors  see image resolution and optical resolution. One factor is the display screen's rectangular shape, which is expressed as the ratio of the physical picture width to the physical picture height. This is known as the aspect ratio. A screen's physical aspect ratio and the individual pixels' aspect ratio may not necessarily be the same. An array of 1280 × 720 on a 16:9 display has square pixels, but an array of 1024 × 768 on a 16:9 display has oblong pixels.

An example of pixel shape affecting "resolution" or perceived sharpness: displaying more information in a smaller area using a higher resolution makes the image much clearer or "sharper". However, most recent screen technologies are fixed at a certain resolution; making the resolution lower on these kinds of screens will greatly decrease sharpness, as an interpolation process is used to "fix" the non-native resolution input into the display's native resolution output.

While some CRT-based displays may use digital video processing that involves image scaling using memory arrays, ultimately "display resolution" in CRT-type displays is affected by different parameters such as spot size and focus, astigmatic effects in the display corners, the color phosphor pitch shadow mask (such as Trinitron) in color displays, and the video bandwidth.

Aspects

A 16:9-ratio television from October 2004 Fatty watching himself on TV.jpg
A 16:9-ratio television from October 2004
Difference between screen sizes in some common devices, such as a Nintendo DS and two laptops shown here. MacBookEeePCNintendoDS.JPG
Difference between screen sizes in some common devices, such as a Nintendo DS and two laptops shown here.

Overscan and underscan

Most television display manufacturers "overscan" the pictures on their displays (CRTs and PDPs, LCDs etc.), so that the effective on-screen picture may be reduced from 720 × 576 (480) to 680 × 550 (450), for example. The size of the invisible area somewhat depends on the display device. Some HD televisions do this as well, to a similar extent.

Computer displays including projectors generally do not overscan although many models (particularly CRT displays) allow it. CRT displays tend to be underscanned in stock configurations, to compensate for the increasing distortions at the corners.

Interlaced versus progressive scan

Interlaced video (also known as interlaced scan) is a technique for doubling the perceived frame rate of a video display without consuming extra bandwidth. The interlaced signal contains two fields of a video frame captured consecutively. This enhances motion perception to the viewer, and reduces flicker by taking advantage of the phi phenomenon.

The European Broadcasting Union has argued against interlaced video in production and broadcasting. The main argument is that no matter how complex the deinterlacing algorithm may be, the artifacts in the interlaced signal cannot be completely eliminated because some information is lost between frames. Despite arguments against it, television standards organizations continue to support interlacing. It is still included in digital video transmission formats such as DV, DVB, and ATSC. New video compression standards like High Efficiency Video Coding are optimized for progressive scan video, but sometimes do support interlaced video.

Progressive scanning (alternatively referred to as noninterlaced scanning) is a format of displaying, storing, or transmitting moving images in which all the lines of each frame are drawn in sequence. This is in contrast to interlaced video used in traditional analog television systems where only the odd lines, then the even lines of each frame (each image called a video field) are drawn alternately, so that only half the number of actual image frames are used to produce video.

Televisions

Current standards

Televisions are of the following resolutions:

Computer monitors

Computer monitors have traditionally possessed higher resolutions than most televisions.

Evolution of Standards

Many personal computers introduced in the late 1970s and the 1980s were designed to use television receivers as their display devices, making the resolutions dependent on the television standards in use, including PAL and NTSC. Picture sizes were usually limited to ensure the visibility of all the pixels in the major television standards and the broad range of television sets with varying amounts of over scan. The actual drawable picture area was, therefore, somewhat smaller than the whole screen, and was usually surrounded by a static-colored border (see image to right). Also, the interlace scanning was usually omitted in order to provide more stability to the picture, effectively halving the vertical resolution in progress. 160 × 200, 320 × 200 and 640 × 200 on NTSC were relatively common resolutions in the era (224, 240 or 256 scanlines were also common). In the IBM PC world, these resolutions came to be used by 16-color EGA video cards.

One of the drawbacks of using a classic television is that the computer display resolution is higher than the television could decode. Chroma resolution for NTSC/PAL televisions are bandwidth-limited to a maximum 1.5 MHz, or approximately 160 pixels wide, which led to blurring of the color for 320- or 640-wide signals, and made text difficult to read (see example image below). Many users upgraded to higher-quality televisions with S-Video or RGBI inputs that helped eliminate chroma blur and produce more legible displays. The earliest, lowest cost solution to the chroma problem was offered in the Atari 2600 Video Computer System and the Apple II+, both of which offered the option to disable the color and view a legacy black-and-white signal. On the Commodore 64, the GEOS mirrored the Mac OS method of using black-and-white to improve readability.

The 640 × 400i resolution (720 × 480i with borders disabled) was first introduced by home computers such as the Commodore Amiga and, later, Atari Falcon. These computers used interlace to boost the maximum vertical resolution. These modes were only suited to graphics or gaming, as the flickering interlace made reading text in word processor, database, or spreadsheet software difficult. (Modern game consoles solve this problem by pre-filtering the 480i video to a lower resolution. For example, Final Fantasy XII suffers from flicker when the filter is turned off, but stabilizes once filtering is restored. The computers of the 1980s lacked sufficient power to run similar filtering software.)

The advantage of a 720 × 480i overscanned computer was an easy interface with interlaced TV production, leading to the development of Newtek's Video Toaster. This device allowed Amigas to be used for CGI creation in various news departments (example: weather overlays), drama programs such as NBC's seaQuest , The WB's Babylon 5 .

In the PC world, the IBM PS/2 VGA (multi-color) on-board graphics chips used a non-interlaced (progressive) 640 × 480 × 16 color resolution that was easier to read and thus more useful for office work. It was the standard resolution from 1990 to around 1996.[ citation needed ] The standard resolution was 800 × 600 until around 2000. Microsoft Windows XP, released in 2001, was designed to run at 800 × 600 minimum, although it is possible to select the original 640 × 480 in the Advanced Settings window.

Programs designed to mimic older hardware such as Atari, Sega, or Nintendo game consoles (emulators) when attached to multiscan CRTs, routinely use much lower resolutions, such as 160 × 200 or 320 × 400 for greater authenticity, though other emulators have taken advantage of pixelation recognition on circle, square, triangle and other geometric features on a lesser resolution for a more scaled vector rendering. Some emulators, at higher resolutions, can even mimic the aperture grille and shadow masks of CRT monitors.

In 2002, 1024 × 768 eXtended Graphics Array was the most common display resolution. Many web sites and multimedia products were re-designed from the previous 800 × 600 format to the layouts optimized for 1024 × 768.

The availability of inexpensive LCD monitors made the 5∶4 aspect ratio resolution of 1280 × 1024 more popular for desktop usage during the first decade of the 21st century. Many computer users including CAD users, graphic artists and video game players ran their computers at 1600 × 1200 resolution (UXGA) or higher such as 2048 × 1536 QXGA if they had the necessary equipment. Other available resolutions included oversize aspects like 1400 × 1050 SXGA+ and wide aspects like 1280 × 800 WXGA, 1440 × 900 WXGA+, 1680 × 1050 WSXGA+, and 1920 × 1200 WUXGA; monitors built to the 720p and 1080p standard were also not unusual among home media and video game players, due to the perfect screen compatibility with movie and video game releases. A new more-than-HD resolution of 2560 × 1600 WQXGA was released in 30-inch LCD monitors in 2007.

In 2010, 27-inch LCD monitors with the 2560 × 1440 resolution were released by multiple manufacturers, and in 2012, Apple introduced a 2880 × 1800 display on the MacBook Pro. Panels for professional environments, such as medical use and air traffic control, support resolutions up to 4096 × 2160 [3] (or, more relevant for control rooms, 1∶12048 × 2048 pixels). [4] [5]


As of March 2012, 1366 × 768 was the most common display resolution.

Common display resolutions

Further information: List of common resolutions

The following table lists the usage share of display resolutions from two sources, as of June 2020. The numbers are not representative of computer users in general.

Common display resolutions (N/A = not applicable)
Standard Aspect ratio Width (px)Height (px) Megapixels Steam [6] (%) StatCounter [7] (%)
nHD 16:96403600.230N/A0.47
SVGA 4:38006000.480N/A0.76
XGA 4:310247680.7860.382.78
WXGA 16:912807200.9220.364.82
WXGA 16:1012808001.0240.613.08
SXGA 5:4128010241.3111.242.47
HD ≈16:913607681.0441.551.38
HD ≈16:913667681.04910.2223.26
WXGA+ 16:1014409001.2963.126.98
N/A16:915368641.327N/A8.53
HD+ 16:916009001.4402.594.14
WSXGA+ 16:10168010501.7641.972.23
FHD 16:9192010802.07464.8120.41
WUXGA 16:10192012002.3040.810.93
QWXGA 16:9204811522.359N/A0.51
N/A ≈21:9256010802.7651.13N/A
QHD 16:9256014403.6866.232.15
N/A ≈21:9344014404.9540.87N/A
4K UHD 16:9384021608.2942.12N/A
Other2.0015.09

In recent years the 16:9 aspect ratio has become more common in notebook displays. 1366 × 768 (HD) has become popular for most low-cost notebooks, while 1920 × 1080 (FHD) and higher resolutions are available for more premium notebooks.

When a computer display resolution is set higher than the physical screen resolution (native resolution), some video drivers make the virtual screen scrollable over the physical screen thus realizing a two dimensional virtual desktop with its viewport. Most LCD manufacturers do make note of the panel's native resolution as working in a non-native resolution on LCDs will result in a poorer image, due to dropping of pixels to make the image fit (when using DVI) or insufficient sampling of the analog signal (when using VGA connector). Few CRT manufacturers will quote the true native resolution, because CRTs are analog in nature and can vary their display from as low as 320 × 200 (emulation of older computers or game consoles) to as high as the internal board will allow, or the image becomes too detailed for the vacuum tube to recreate (i.e., analog blur). Thus, CRTs provide a variability in resolution that fixed resolution LCDs cannot provide.

Film industry

As far as digital cinematography is concerned, video resolution standards depend first on the frames' aspect ratio in the film stock (which is usually scanned for digital intermediate post-production) and then on the actual points' count. Although there is not a unique set of standardized sizes, it is commonplace within the motion picture industry to refer to "nK" image "quality", where n is a (small, usually even) integer number which translates into a set of actual resolutions, depending on the film format. As a reference consider that, for a 4:3 (around 1.33:1) aspect ratio which a film frame (no matter what is its format) is expected to horizontally fit in, n is the multiplier of 1024 such that the horizontal resolution is exactly 1024•n points.[ citation needed ] For example, 2K reference resolution is 2048 × 1536 pixels, whereas 4K reference resolution is 4096 × 3072 pixels. Nevertheless, 2K may also refer to resolutions like 2048 × 1556 (full-aperture), 2048 × 1152 (HDTV, 16:9 aspect ratio) or 2048 × 872 pixels (Cinemascope, 2.35:1 aspect ratio). It is also worth noting that while a frame resolution may be, for example, 3:2 (720 × 480 NTSC), that is not what you will see on-screen (i.e. 4:3 or 16:9 depending on the intended aspect ratio of the original material).

See also

Related Research Articles

Computer monitor Computer output device

A computer monitor is an output device that displays information in pictorial form. A monitor usually comprises the visual display, circuitry, casing, and power supply. The display device in modern monitors is typically a thin film transistor liquid crystal display (TFT-LCD) with LED backlighting having replaced cold-cathode fluorescent lamp (CCFL) backlighting. Previous monitors used a cathode ray tube (CRT). Monitors are connected to the computer via VGA, Digital Visual Interface (DVI), HDMI, DisplayPort, USB-C, low-voltage differential signaling (LVDS) or other proprietary connectors and signals.

Video Electronic moving image

Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode ray tube (CRT) systems which were later replaced by flat panel displays of several types.

Interlaced video

Interlaced video is a technique for doubling the perceived frame rate of a video display without consuming extra bandwidth. The interlaced signal contains two fields of a video frame captured consecutively. This enhances motion perception to the viewer, and reduces flicker by taking advantage of the phi phenomenon.

Progressive scanning is a format of displaying, storing, or transmitting moving images in which all the lines of each frame are drawn in sequence. This is in contrast to interlaced video used in traditional analog television systems where only the odd lines, then the even lines of each frame are drawn alternately, so that only half the number of actual image frames are used to produce video. The system was originally known as "sequential scanning" when it was used in the Baird 240 line television transmissions from Alexandra Palace, United Kingdom in 1936. It was also used in Baird's experimental transmissions using 30 lines in the 1920s. Progressive scanning became universally used in computer screens beginning in the early 21st century.

A plasma display panel (PDP) is a type of flat panel display that uses small cells containing plasma: ionized gas that responds to electric fields. Plasma TVs were the first large flat panel displays to be released to the public.

Apple Inc. sold a variety of LCD and CRT computer displays in the past. Apple paused production of their own standalone displays in 2016 and partnered with LG to design displays for Macs. In June 2019, the Pro Display XDR was introduced. It is currently the only Apple-branded display available.

The refresh rate is the number of times per second that a raster-based display device displays a new image. This is independent from frame rate, which describes how many images are stored or generated every second by the device driving the display.

480p is the shorthand name for a family of video display resolutions. The p stands for progressive scan, i.e. non-interlaced. The 480 denotes a vertical resolution of 480 pixels, usually with a horizontal resolution of 640 pixels and 4:3 aspect ratio or a horizontal resolution of 854 or less pixels for an approximate 16:9 aspect ratio. Since a pixel count must be a whole number, in Wide VGA displays it is generally rounded up to 854 to ensure inclusion of the entire image. The frames are displayed progressively as opposed to interlaced. 480p was used for many early plasma televisions. Standard definition has always been a 4:3 aspect ratio with a pixel resolution of 640 × 480 at 60Hz for NTSC regions, and 720 or 768 × 576 for PAL regions (1024 wide for widescreen displays. However, standard definition defines a 15.7Khz horizontal scanrate, which means that interlacing has to be used for those resolution modes. The lowercase letter "p" in 480p stands for progressive, so the two must not be confused.

1080i is a combination of frame resolution and scan type. 1080i is used in high-definition television (HDTV) and high-definition video. The number "1080" refers to the number of horizontal lines on the screen. The "i" is an abbreviation for "interlaced"; this indicates that only the odd lines, then the even lines of each frame are drawn alternately, so that only half the number of actual image frames are used to produce video. A related display resolution is 1080p, which also has 1080 lines of resolution; the "p" refers to progressive scan, which indicates that the lines of resolution for each frame are "drawn" on the screen in sequence.

Image resolution is the detail an image holds. The term applies to raster digital images, film images, and other types of images. Higher resolution means more image detail.

576p is the shorthand name for a video display resolution. The p stands for progressive scan, i.e. non-interlaced, the 576 for a vertical resolution of 576 pixels, usually with a horizontal resolution of 768 or 1024, depending of the relationship aspect. The 576p quality was decided as the default quality when converting from VHS to digital. 576p is considered standard definition for PAL video. The frame rate can be given explicitly after the letter.

High-definition video is video of higher resolution and quality than standard-definition. While there is no standardized meaning for high-definition, generally any video image with considerably more than 480 vertical scan lines or 576 vertical lines (Europe) is considered high-definition. 480 scan lines is generally the minimum even though the majority of systems greatly exceed that. Images of standard resolution captured at rates faster than normal, by a high-speed camera may be considered high-definition in some contexts. Some television series shot on high-definition video are made to look as if they have been shot on film, a technique which is often known as filmizing.

Native resolution

The native resolution of a LCD, LCoS or other flat panel display refers to its single fixed resolution. As an LCD consists of a fixed raster, it cannot change resolution to match the signal being displayed as a CRT monitor can, meaning that optimal display quality can be reached only when the signal input matches the native resolution. An image where the number of pixels is the same as in the image source and where the pixels are perfectly aligned to the pixels in the source is said to be pixel perfect.

CRT projector Older type of video projector that uses small, high intensity CRTs as image generating elements

A CRT projector is a video projector that uses a small, high-brightness cathode ray tube as the image generating element. The image is then focused and enlarged onto a screen using a lens kept in front of the CRT face. The first color CRT projectors came out in the early 1950s. Most modern CRT projectors are color and have three separate CRTs, and their own lenses to achieve color images. The red, green and blue portions of the incoming video signal are processed and sent to the respective CRTs whose images are focused by their lenses to achieve the overall picture on the screen. Various designs have made it to production, including the "direct" CRT-lens design, and the Schmidt CRT, which employed a phosphor screen that illuminates a perforated spherical mirror, all within an evacuated "tube."

Pixel aspect ratio

Pixel aspect ratio is a mathematical ratio that describes how the width of a pixel in a digital image compares to the height of that pixel.

A multiple-sync (multisync) monitor, also known as a multiscan or multimode monitor, is a raster-scan analog video monitor that can properly synchronise with multiple horizontal and vertical scan rates. In contrast, fixed frequency monitors can only synchronise with a specific set of scan rates. They are generally used for computer displays, but sometimes for television, and the terminology is mostly applied to CRT displays although the concept applies to other technologies.

The technology of television has evolved since its early days using a mechanical system invented by Paul Gottlieb Nipkow in 1884. Every television system works on the scanning principle first implemented in the rotating disk scanner of Nipkow. This turns a two-dimensional image into a time series of signals that represent the brightness and color of each resolvable element of the picture. By repeating a two-dimensional image quickly enough, the impression of motion can be transmitted as well. For the receiving apparatus to reconstruct the image, synchronization information is included in the signal to allow proper placement of each line within the image and to identify when a complete image has been transmitted and a new image is to follow.

Graphics display resolution Width and height of an electronic visual display device, such as a computer monitor, in pixels

The graphics display resolution is the width and height dimension of an electronic visual display device, such as a computer monitor, in pixels. Certain combinations of width and height are standardized and typically given a name and an initialism that is descriptive of its dimensions. A higher display resolution in a display of the same size means that displayed photo or video content appears sharper, and pixel art appears smaller.

Ultrawide formats

Ultrawide formats refers to photos, videos and displays with aspect ratio greater than 2. There were multiple moves in history towards wider formats, including one by Disney, with some of them being more successful than others.

References

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