Computer display standard

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Display standards comparison. Sizes are colored in blue, red, yellow, green, and purple to represent aspect ratio

Various computer display standards or display modes have been used in the history of the personal computer. They are often a combination of display resolution (specified as the width and height in pixels), color depth (measured in bits), and refresh rate (expressed in hertz). Associated with the screen resolution and refresh rate is a display adapter. Earlier display adapters were simple frame-buffers, but later display standards also specified a more extensive set of display functions and software controlled interface.

Until about 2003, most computer monitors had a 4:3 aspect ratio and some had 5:4. Between 2003 and 2006, monitors with 16:10 aspect ratios have become commonly available, first in laptops and later also in standalone monitors. Productive uses for such monitors, i.e. besides widescreen movie viewing and computer game play, are the word-processor display of two standard letter pages side by side, as well as CAD displays of large-size drawings and CAD application menus at the same time. The VESA industry organization has defined several standards related to power management and device identification. Ergonomics standards are set by the TCO.

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[edit] Standards

A number of common resolutions have been used with computers descended from the original IBM PC. Some of these are now supported by other families of personal computers. These are de-facto standards, usually originated by one manufacturer and reverse-engineered by others, though the VESA group has co-ordinated the efforts of several leading video display adapter manufacturers. Video standards associated with IBM-PC-descended personal computers include:

Table of computer display standards
Video standard Full name Description Display resolution (pixels) Aspect ratio Color depth (2^bpp colors)
unnamed unnamed Various Apple Inc., Atari, Commodore PCs introduced from 1977 to 1982. They used TVs for their displays. 320×200i (approximately) 4:3 16 to 128 colors.
unnamed unnamed Commodore Amiga, Atari ST, and others. They used NTSC or PAL-compliant RGB component displays. 720×480i (approximately) 4:3 4096 colors.
MDA Monochrome Display Adapter The original standard on IBM PCs and IBM PC XTs with 4 KB video RAM. Introduced in 1981 by IBM. Supports text mode only. 720×350 (text) 72:35 1 bpp
CGA Color Graphics Adapter Introduced in 1981 by IBM, as the first color display standard for the IBM PC. The standard CGA graphics cards were equipped with 16 KB video RAM. 640×200 (128k)
320×200 (64k)
160×200 (32k)
16:5
16:10
4:5
1 bpp
2 bpp
4 bpp
Hercules A monochrome display capable of sharp text and graphics for its time of introduction. Very popular with the Lotus 1-2-3 spreadsheet, which was one of the PC's first killer apps. Introduced in 1982. 720×348 (250.5k) 60:29 1 bpp
EGA Enhanced Graphics Adapter Introduced in 1984 by IBM. A resolution of 640 × 350 pixels of 16 different colors (4 bits per pixel, or bpp), selectable from a 64-color palette (2 bits per each of red-green-blue). 640×350 (224k) 64:35 4 bpp
Professional Graphics Controller With on-board 2D and 3D acceleration introduced in 1984 for the 8-bit PC-bus, intended for CAD applications, a triple-board display adapter with built-in processor, and displaying video with a 60 Hz frame rate. 640×480 (307k) 4:3 8 bpp
MCGA Multicolor Graphics Adapter Introduced on selected PS/2 models in 1987, with reduced cost compared to VGA. MCGA had a 320x200 256 color (from a 262,144 color palette) mode, and a 640x480 mode only in monochrome due to 64k video memory, compared to the 256k memory of VGA. 320×200 (64k)
640×480 (307k)
16:10
4:3
8 bpp
1 bpp
8514 Precursor to XGA and released about the same time as VGA in 1987. 8514/A cards displayed interlaced video at 43.5 Hz. 1024×768 (786k) 4:3 8 bpp
VGA Video Graphics Array Introduced in 1987 by IBM. VGA is actually a set of different resolutions, but is most commonly used today to refer to 640 × 480 pixel displays with 16 colors (4 bits per pixel) and a 4:3 aspect ratio. Other display modes are also defined as VGA, such as 320 × 200 at 256 colors (8 bits per pixel) and a text mode with 720 × 400 pixels. VGA displays and adapters are generally capable of Mode X graphics, an undocumented mode to allow increased non-standard resolutions. 640×480 (307k)
640×350 (224k)
320×200 (64k)
720×400 (text)
4:3
64:35
16:10
9:5
4 bpp
4 bpp
4/8 bpp
4 bpp
SVGA Super VGA A video display standard created by VESA for IBM PC compatible personal computers. Introduced in 1989. 800×600 (480k) 4:3 4 bpp
XGA Extended Graphics Array An IBM display standard introduced in 1990. XGA-2 added 1024 × 768 support for high color and higher refresh rates, improved performance, and support for 1360 × 1024 in 16 colors (4 bits per pixel). 1024×768 (786k)
640×480 (307k)
4:3
4:3
8 bpp
16 bpp
XGA+ Extended Graphics Array Plus Although not an official name, this term is now used to refer to 1152 x 864, which is the largest 4:3 array yielding under one million pixels. Variants of this were used by Apple Computer (at 1152x870) and Sun Microsystems (at 1152x900) for 21-inch CRT displays. 1152×864 (995k)
640×480 (307k)
4:3
4:3
8 bpp
16 bpp
QVGA Quarter VGA 320×240 (75k) 4:3
WQVGA Wide QVGA 480×272 (127.5k) 16:9
HQVGA Half QVGA 240×160 (38k) 3:2
QQVGA Quarter QVGA 160×120 (19k) 4:3
unnamed unnamed A common size for LCDs manufactured for small consumer electronics and mobile phones, typically in a 1.7" to 1.9" diagonal size. This LCD is often used in the portrait (128×160) orientation. The unusual 5:4 aspect ratio makes the display slightly different from the QQVGA dimensions. 160×128 (20k) 5:4
WXGA Widescreen Extended Graphics Array A version of the XGA format. This display aspect ratio is becoming popular in some recent notebook computers. 1280×720 (922k)
1280×800 (1024k)
1440×900 (1296k)
16:9 or 16:10 32 bpp
SXGA Super XGA A widely used de facto 32 bit Truecolor standard, with an unusual aspect ratio of 5:4 (1.25:1) instead of the more common 4:3 (1.33:1), which means that 4:3 pictures and video will appear letterboxed on the narrower 5:4 screens. This is generally the physical aspect ratio & native resolution of standard 17" and 19" LCD monitors.
  • Some manufacturers, noting that the de facto industry standard was VGA (Video Graphics Array), termed this the Extended Video Graphics Array or XVGA.
1280×1024 (1310k) 5:4 32 bpp
WXGA+,
or WXGA,
(or WSXGA)
Widescreen Extended Graphics Array PLUS A version of the WXGA format. This display aspect ratio is becoming popular in some recent notebook computers, and is the native resolution for many 19" widescreen LCD monitors. 1440×900 (1296k) 16:10 32 bpp
WSXGA+ Widescreen Super Extended Graphics Array Plus A version of the WXGA format. This is the native resolution for many 22" widescreen LCD monitors. 1680×1050 (1764k) 16:10 32 bpp
UXGA Ultra XGA A de facto Truecolor standard. This is the native resolution for many 20" LCD monitors. 1600×1200 (1920k) 4:3 32 bpp
WUXGA Widescreen Ultra Extended Graphics Array A version of the UXGA format. This display aspect ratio was becoming popular in high end 15" and 17" widescreen notebook computers. This is the native resolution for many 24"-27" widescreen LCD monitors. 1920×1200 (2304k) 16:10 32 bpp
2K DLP Cinema Technology Digital Film Projection 2048×1080 (2212k) 1.9 48 bpp - 24 FPS
QXGA Quad Extended Graphics Array 2048×1536 (3146k) 4:3 32 bpp
QWXGA Quad Wide Extended Graphics Array Samsung have taken the wraps off of the company’s first QWXGA resolution 23-inch LCD monitor 2342BWX 2048×1152 (2359k) 16:9
WQXGA Widescreen Quad Extended Graphics Array A version of the XGA format. This is the native resolution for many 30" widescreen LCD monitors. 2560×1600 (4096k) 16:10 32 bpp
QSXGA Quad Super Extended Graphics Array 2560×2048 (5243k) 5:4 32 bpp
WQSXGA Wide Quad Super Extended Graphics Array 3200×2048 (6554k) 25:16 32 bpp
QUXGA Quad Ultra Extended Graphics Array 3200×2400 (7680k) 4:3 32 bpp
WQUXGA Wide Quad Ultra Extended Graphics Array The IBM T220/T221 LCD monitors supported this resolution, but they are no longer available. 3840×2400 (9216k) 16:10 32 bpp
4K DLP Cinema Technology Digital Film Projection 4096×1716 (7029k) 2.39 48 bpp - 24 FPS
HXGA Hex[adecatuple] Extended Graphics Array 4096×3072 (12583k) 4:3 32 bpp
WHXGA Wide Hex[adecatuple] Extended Graphics Array 5120×3200 (16384k) 16:10 32 bpp
HSXGA Hex[adecatuple] Super Extended Graphics Array 5120×4096 (20972k) 5:4 32 bpp
WHSXGA Wide Hex[adecatuple] Super Extended Graphics Array 6400×4096 (26214k) 25:16 32 bpp
HUXGA Hex[adecatuple] Ultra Extended Graphics Array 6400×4800 (30720k) 4:3 32 bpp
WHUXGA Wide Hex[adecatuple] Ultra Extended Graphics Array 7680×4800 (36864k) 16:10 32 bpp

[edit] Display resolution prefixes

Although the common standard prefixes super and ultra do not indicate specific modifiers to base standard resolutions, several others do:

Quarter (Q)
A quarter of the base resolution. E.g. QVGA, a term for a 320×240 resolution, half the width and height of VGA, hence the quarter total resolution. This prefix is usually for "Quad" in higher resolutions.
Wide (W)
The base resolution increased, and not lowered, for square or near-square pixels on a widescreen display, usually with an aspect ratio of either 16:9 or 16:10.
Quad(ruple) (Q)
Four times as many pixels compared to the base resolution, i.e. twice the horizontal and vertical resolution respectively.
Hex(adecatuple) (H)
Sixteen times as many pixels compared to the base resolution, i.e. four times the horizontal and vertical resolutions respectively.
Ultra (U)
eXtended (X)

These prefixes are also often combined, as in WQXGA or WHUXGA.

[edit] Other resolutions

There are also some other 4:3 ratio resolutions such as 1400x1050 SXGA+ and unnamed ones like 1152x864 (sometimes referred to as XGA+).

[edit] See also

[edit] External links


This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.

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