lcd panel test video supplier
Looking for wholesale video test monitor? Look no further than Alibaba.com, one of the largest collections of wholesale shipment suppliers in the world. We have a huge range of lcd computer monitor options and lcd display screen options to choose from. Whether you need a small lcd screen or a large one, we have you covered.
These video test monitor products have become the go to display types for computers today. With tft color monitors slowly being phased out, lcd computer monitor displays are the standard in the industry. All customers need a flat screen computer monitor to interact with their personal computers. For ardent gamers that require high refresh rates to minimize lagging and make use of high performance computers there are a range of lcd gaming monitors available.
We also have more specialised products like rack mounted monitors for IT administrators and network administrators working in commercial settings. These monitors are used to oversee large server rooms and network infrastructure. New transparent lcd screen options are also coming on the market that are futuristic and allow for a sleek look to fit modern aesthetics.
So, start ordering your shipment of video test monitor today from our suppliers. They are ready and willing to answer any questions you may have about their products and get you started today!
Westar’s family of LCD Testers are supported by our Tooling Solutions. A tooling solution allows you, the customer, to use our LCD Tester to test a particular display. Tooling solutions are developed cost-effectively by our support staff, saving you time and money for your test functions.
For quickest delivery of tooling solutions, we ask that you supply a sample display, along with its specification or datasheet. Our tooling specialists will use this information to create a tooling solution. We have already developed hundreds of tooling solutions for many common LCD panels. Just ask our support staff if we have a solution already complete!
Our cabling solutions are delivered with schematics to allow you to repair your cables, or build more yourself. Our profiles are ready-to-use on your TFT Tester, already tested at our facility!
In the past decade, LCD monitors have replaced CRT screens for all but the most specialist applications. Although liquid crystal displays boast perfect
The RTCRST jumper allows you to clear NVRAM. The NVRAM is cleared when the jumper is closed. (You can use the jumper from the password bridge.) Remember that it is always best practice to remove the power cable from the personal computer before opening the lid or access panel and going inside. To clear the CMOS, AC power must be applied to the computer for about 10 seconds while the jumper is closed. (This does not necessarily mean turning the computer on, putting power across the motherboard is enough.) Browse to
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The display in modern monitors is typically an LCD with LED backlight, having by the 2010s replaced CCFL backlit LCDs. Before the mid-2000s,CRT. Monitors are connected to the computer via DisplayPort, HDMI, USB-C, DVI, VGA, or other proprietary connectors and signals.
Originally, computer monitors were used for data processing while television sets were used for video. From the 1980s onward, computers (and their monitors) have been used for both data processing and video, while televisions have implemented some computer functionality. In the 2000s, the typical display aspect ratio of both televisions and computer monitors has changed from 4:3 to 16:9.
Early electronic computer front panels were fitted with an array of light bulbs where the state of each particular bulb would indicate the on/off state of a particular register bit inside the computer. This allowed the engineers operating the computer to monitor the internal state of the machine, so this panel of lights came to be known as the "monitor". As early monitors were only capable of displaying a very limited amount of information and were very transient, they were rarely considered for program output. Instead, a line printer was the primary output device, while the monitor was limited to keeping track of the program"s operation.
Multiple technologies have been used for computer monitors. Until the 21st century most used cathode-ray tubes but they have largely been superseded by LCD monitors.
The first computer monitors used cathode-ray tubes (CRTs). Prior to the advent of home computers in the late 1970s, it was common for a video display terminal (VDT) using a CRT to be physically integrated with a keyboard and other components of the workstation in a single large chassis, typically limiting them to emulation of a paper teletypewriter, thus the early epithet of "glass TTY". The display was monochromatic and far less sharp and detailed than on a modern monitor, necessitating the use of relatively large text and severely limiting the amount of information that could be displayed at one time. High-resolution CRT displays were developed for specialized military, industrial and scientific applications but they were far too costly for general use; wider commercial use became possible after the release of a slow, but affordable Tektronix 4010 terminal in 1972.
By the end of the 1980s color progressive scan CRT monitors were widely available and increasingly affordable, while the sharpest prosumer monitors could clearly display high-definition video, against the backdrop of efforts at HDTV standardization from the 1970s to the 1980s failing continuously, leaving consumer SDTVs to stagnate increasingly far behind the capabilities of computer CRT monitors well into the 2000s. During the following decade, maximum display resolutions gradually increased and prices continued to fall as CRT technology remained dominant in the PC monitor market into the new millennium, partly because it remained cheaper to produce.
There are multiple technologies that have been used to implement liquid-crystal displays (LCD). Throughout the 1990s, the primary use of LCD technology as computer monitors was in laptops where the lower power consumption, lighter weight, and smaller physical size of LCDs justified the higher price versus a CRT. Commonly, the same laptop would be offered with an assortment of display options at increasing price points: (active or passive) monochrome, passive color, or active matrix color (TFT). As volume and manufacturing capability have improved, the monochrome and passive color technologies were dropped from most product lines.
The first standalone LCDs appeared in the mid-1990s selling for high prices. As prices declined they became more popular, and by 1997 were competing with CRT monitors. Among the first desktop LCD computer monitors was the Eizo FlexScan L66 in the mid-1990s, the SGI 1600SW, Apple Studio Display and the ViewSonic VP140vision science remain dependent on CRTs, the best LCD monitors having achieved moderate temporal accuracy, and so can be used only if their poor spatial accuracy is unimportant.
High dynamic range (HDR)television series, motion pictures and video games transitioning to widescreen, which makes squarer monitors unsuited to display them correctly.
Organic light-emitting diode (OLED) monitors provide most of the benefits of both LCD and CRT monitors with few of their drawbacks, though much like plasma panels or very early CRTs they suffer from burn-in, and remain very expensive.
Dot pitch represents the distance between the primary elements of the display, typically averaged across it in nonuniform displays. A related unit is pixel pitch, In LCDs, pixel pitch is the distance between the center of two adjacent pixels. In CRTs, pixel pitch is defined as the distance between subpixels of the same color. Dot pitch is the reciprocal of pixel density.
Pixel density is a measure of how densely packed the pixels on a display are. In LCDs, pixel density is the number of pixels in one linear unit along the display, typically measured in pixels per inch (px/in or ppi).
Contrast ratio is the ratio of the luminosity of the brightest color (white) to that of the darkest color (black) that the monitor is capable of producing simultaneously. For example, a ratio of 20,000∶1 means that the brightest shade (white) is 20,000 times brighter than its darkest shade (black). Dynamic contrast ratio is measured with the LCD backlight turned off. ANSI contrast is with both black and white simultaneously adjacent onscreen.
Refresh rate is (in CRTs) the number of times in a second that the display is illuminated (the number of times a second a raster scan is completed). In LCDs it is the number of times the image can be changed per second, expressed in hertz (Hz). Determines the maximum number of frames per second (FPS) a monitor is capable of showing. Maximum refresh rate is limited by response time.
Response time is the time a pixel in a monitor takes to change between two shades. The particular shades depend on the test procedure, which differs between manufacturers. In general, lower numbers mean faster transitions and therefore fewer visible image artifacts such as ghosting. Grey to grey (GtG), measured in milliseconds (ms).
On two-dimensional display devices such as computer monitors the display size or view able image size is the actual amount of screen space that is available to display a picture, video or working space, without obstruction from the bezel or other aspects of the unit"s design. The main measurements for display devices are: width, height, total area and the diagonal.
With the introduction of flat panel technology, the diagonal measurement became the actual diagonal of the visible display. This meant that an eighteen-inch LCD had a larger viewable area than an eighteen-inch cathode-ray tube.
Until about 2003, most computer monitors had a 4:3 aspect ratio and some had 5:4. Between 2003 and 2006, monitors with 16:9 and mostly 16:10 (8:5) aspect ratios became commonly available, first in laptops and later also in standalone monitors. Reasons for this transition included productive uses (i.e. besides Field of view in video games and movie viewing) such as the word processor display of two standard letter pages side by side, as well as CAD displays of large-size drawings and application menus at the same time.LCD monitors and the same year 16:10 was the mainstream standard for laptops and notebook computers.
In 2011, non-widescreen displays with 4:3 aspect ratios were only being manufactured in small quantities. According to Samsung, this was because the "Demand for the old "Square monitors" has decreased rapidly over the last couple of years," and "I predict that by the end of 2011, production on all 4:3 or similar panels will be halted due to a lack of demand."
Most modern monitors will switch to a power-saving mode if no video-input signal is received. This allows modern operating systems to turn off a monitor after a specified period of inactivity. This also extends the monitor"s service life. Some monitors will also switch themselves off after a time period on standby.
Most modern monitors have two different indicator light colors wherein if video-input signal was detected, the indicator light is green and when the monitor is in power-saving mode, the screen is black and the indicator light is orange. Some monitors have different indicator light colors and some monitors have blinking indicator light when in power-saving mode.
Some displays, especially newer flat panel monitors, replace the traditional anti-glare matte finish with a glossy one. This increases color saturation and sharpness but reflections from lights and windows are more visible. Anti-reflective coatings are sometimes applied to help reduce reflections, although this only partly mitigates the problem.
Most often using nominally flat-panel display technology such as LCD or OLED, a concave rather than convex curve is imparted, reducing geometric distortion, especially in extremely large and wide seamless desktop monitors intended for close viewing range.
Raw monitors are raw framed LCD monitors, to install a monitor on a not so common place, ie, on the car door or you need it in the trunk. It is usually paired with a power adapter to have a versatile monitor for home or commercial use.
The Flat Display Mounting Interface (FDMI), also known as VESA Mounting Interface Standard (MIS) or colloquially as a VESA mount, is a family of standards defined by the Video Electronics Standards Association for mounting flat panel displays to stands or wall mounts.
A fixed rack mount monitor is mounted directly to the rack with the flat-panel or CRT visible at all times. The height of the unit is measured in rack units (RU) and 8U or 9U are most common to fit 17-inch or 19-inch screens. The front sides of the unit are provided with flanges to mount to the rack, providing appropriately spaced holes or slots for the rack mounting screws. A 19-inch diagonal screen is the largest size that will fit within the rails of a 19-inch rack. Larger flat-panels may be accommodated but are "mount-on-rack" and extend forward of the rack. There are smaller display units, typically used in broadcast environments, which fit multiple smaller screens side by side into one rack mount.
A stowable rack mount monitor is 1U, 2U or 3U high and is mounted on rack slides allowing the display to be folded down and the unit slid into the rack for storage as a drawer. The flat display is visible only when pulled out of the rack and deployed. These units may include only a display or may be equipped with a keyboard creating a KVM (Keyboard Video Monitor). Most common are systems with a single LCD but there are systems providing two or three displays in a single rack mount system.
A panel mount computer monitor is intended for mounting into a flat surface with the front of the display unit protruding just slightly. They may also be mounted to the rear of the panel. A flange is provided around the screen, sides, top and bottom, to allow mounting. This contrasts with a rack mount display where the flanges are only on the sides. The flanges will be provided with holes for thru-bolts or may have studs welded to the rear surface to secure the unit in the hole in the panel. Often a gasket is provided to provide a water-tight seal to the panel and the front of the screen will be sealed to the back of the front panel to prevent water and dirt contamination.
An open frame monitor provides the display and enough supporting structure to hold associated electronics and to minimally support the display. Provision will be made for attaching the unit to some external structure for support and protection. Open frame monitors are intended to be built into some other piece of equipment providing its own case. An arcade video game would be a good example with the display mounted inside the cabinet. There is usually an open frame display inside all end-use displays with the end-use display simply providing an attractive protective enclosure. Some rack mount monitor manufacturers will purchase desktop displays, take them apart, and discard the outer plastic parts, keeping the inner open-frame display for inclusion into their product.
Van Eck phreaking is the process of remotely displaying the contents of a CRT or LCD by detecting its electromagnetic emissions. It is named after Dutch computer researcher Wim van Eck, who in 1985 published the first paper on it, including proof of concept. Phreaking more generally is the process of exploiting telephone networks.
Masoud Ghodrati, Adam P. Morris, and Nicholas Seow Chiang Price (2015) The (un)suitability of modern liquid crystal displays (LCDs) for vision research. Frontiers in Psychology, 6:303.
To play streaming high dynamic range (HDR) video in Windows 10 (version 1803 or later), the built-in display for your laptop, tablet, or 2-in-1 PC needs to support HDR. To find the specifications for a specific laptop or tablet, visit the device manufacturer’s website.
The Windows 10 device needs to have an integrated graphics card that supports PlayReady hardware digital rights management (for protected HDR content), and it must have the required codecs installed for 10-bit video decoding. Devices using modern processors support this capability. Common codecs required for this include HEVC, AV1, and VP9, which can be obtained from the Microsoft Store: HEVC Video Extensions, VP9 Video Extensions, AV1 Video Extension.
The Windows 10 device needs to have an integrated graphics card that supports PlayReady hardware digital rights management (for protected HDR content), and it must have the required codecs installed for 10-bit video decoding. Devices using modern processors support this capability. Common codecs required for this include HEVC, AV1, and VP9, which can be obtained from the Microsoft Store: HEVC Video Extensions, VP9 Video Extensions, AV1 Video Extension.
Note: If the Stream HDR video switch was off when you upgraded from version 1809 to version 1903 or later, the Stream HDR video switch won"t enable, preventing you from streaming high-dynamic-range (HDR) videos. To work around this issue, see KB4512062, "Stream HDR video" can"t be enabled when switched off before upgrading to Windows 10, version 1903 or later.
To play streaming high dynamic range (HDR) video in Windows 10, your external display and Windows 10 PC need to support HDR. To find the specifications for a specific PC or external display, visit the device manufacturer’s website. Here are the requirements:
The Windows 10 device needs to have a graphics card that supports PlayReady digital rights management (for protected HDR content), and it must have the required codecs installed for 10-bit video decoding. Devices using modern processors support this capability. Common codecs required for this include HEVC, AV1, and VP9 codecs, which can be obtained from the Microsoft Store: HEVC Video Extensions, VP9 Video Extensions, AV1 Video Extension.
We recommend that you have the latest graphics drivers (WDDM) installed on your Windows 10 PC. To get the latest drivers, go to Windows Update in Settings, or check your PC manufacturer"s website.
A close look at the video input interfaces used in LCD monitors. With the emergence of a new generation of interfaces, growing numbers of LCD monitors feature multiple and different interfaces. Image quality and ease of use are likely to depend on how well the user knows and uses the unique characteristics of each interface when connecting the appropriate devices.
Note: Below is the translation from the Japanese of the "IT Media LCD Display Course II, Part 2," published on December 16, 2008. Copyright 2011 ITmedia Inc. Information about Mini DisplayPort was added to the English translation.
Driven by demand for higher-resolution monitor environments and the proliferation of high-definition devices, the types of video input interfaces ("interfaces" hereinafter) found in LCD monitors continue to proliferate. More than likely, significant numbers of users encountering LCD monitors incorporating multiple input systems have wondered what to connect to which terminal. In this article, we"ll discuss, one by one, the main interfaces used today. But first, let"s give an overview of the types of interfaces available.
The interfaces for LCD monitors designed for use with PCs can be grouped into two categories: analog interfaces, carryovers from the days of CRT monitors, and the digital interfaces developed more recently. An analog interface involves the additional steps of conversion of digital signals within the PC to analog signals for output and the conversion of these analog signals back into digital form by the LCD monitor receiving the signal. This series of actions can degrade image quality. (Image quality also depends on the quality of the route used in converting from analog to digital.) A digital interface offers superior image quality, since it transmits digital signals without conversion or modification.
LCD-monitor interfaces also can be grouped by differences in the devices connected. Major categories here are inputs from PCs and inputs from audio-video (AV) devices. PC input generally involves one of the following five interface types: D-Sub for analog connections; DVI-D for digital connections; DVI-I, which is compatible with both analog and digital connections; and HDMI and DisplayPort, representing the new generation of interfaces for digital connections. Other more recent adapters input and output PC RGB signals and LCD monitors using USB as a video input interface.
The main AV input interfaces are composite video, S-Video, component video, D1 – 5, and HDMI. All of these other than the new HDMI standard use analog connections. As with PC input, a digital HDMI connection generally provides better image quality for AV input than the various analog connection interfaces.
It"s worth noting that while HDMI was designed for use with AV input and output, the standard also supports PC input and output. LCD monitors incorporating HDMI ports include some that support PC input officially and others that—whether or not they can display PC input—do not support PC input officially.
When used as a monitor interface, a D-Sub port is also known as a VGA port, an analog connection standard that"s been around for some time. The connector is a DE-15 connector with 15 pins in three rows, often referred to as a "mini-D-Sub 15-pin" or "D-Sub 15-pin" connector. (Some connectors omit unused pins.) D-Sub is currently the most widely used monitor interface, compatible with very large numbers of PCs and LCD monitors.
Keep in mind that there are two types of mainstream DVI-D digital connections: single link and dual link. For a single-link DVI-D connection, the maximum resolution that can be displayed is 1920 × 1200 pixels (WUXGA). Higher resolutions (such as 2560 × 1600 pixels) require a dual-link DVI-D connection providing double the bandwidth of a single-link DVI-D (7.4 Gb/second or higher). To use a dual-link DVI-D connection, the DVI-D input on the LCD monitor side, the DVI-D output on the PC side, and the DVI-D cable must all be compatible with the dual-link DVI-D standard.
DVI-I, the other DVI standard, can be used with both digital and analog connections, depending on the monitor cable used. Since a DVI-I analog signal is compatible with the D-Sub standard, an analog connection can be formed by using a monitor cable with a D-Sub connector on one end and a DVI-I connector on the other. Depending on the cable and the connectors on the PC side and on the LCD-monitor side, it may also be possible to use an adapter for connecting a DVI-I connector with a D-Sub connector.
Monitor cables with DVI-I connectors on both ends were available at one time. These are rare today, since this configuration made it difficult to determine whether the connection was digital or analog and generated frequent connection issues. Having DVI-I connectors on both the PC side and the LCD monitor side can lead to confusion. In such cases, the ideal configuration is a digital connection made with a DVI-D cable.
As the latest digital interfaces, the High-Definition Multimedia Interface (HDMI), DisplayPort, and Mini DisplayPort have attracted considerable attention. All standards offer the capacity to transfer both audio and video signals digitally using a single cable; all offer easy cable attachment and removal.
The HDMI, DisplayPort, and Mini DisplayPort standards also are compatible with the High-Bandwidth Digital Content Protection System (HDCP). A technology intended to protect copyright on digital content, HDCP allows authorization of both output and input devices before video is displayed.
Another feature is that HDMI, DisplayPort, and Mini DisplayPort video signals can be converted back and forth with the DVI-D standard, a PC digital interface. Using the appropriate conversion adapter or cable, we can output video from a DVI-D, HDMI, DisplayPort, and Mini DisplayPort connector and input to any of these options. Currently, however, this implementation appears to be imperfect: In certain cases, input and output devices are not completely compatible (i.e., video does not display).
While HDMI, DisplayPort, and Mini DisplayPort each can transmit both audio and video using a single cable, DVI-D can transmit only video and requires separate input/output ports and cables for audio. For this reason, when converting between the DVI-D and HDMI, DisplayPort or Mini DisplayPort standards, only video can be transmitted over a single cable. (Some products can transmit audio from the DVI side via a conversion adapter.)
Now a standard interface for devices (primarily televisions and recorders), HDMI was established in December 2002 by Sony, Toshiba, Thomson Multimedia, Panasonic (formerly Matsushita), Hitachi, and Philips, led by Silicon Image. HDMI video signals are based on the DVI-D standard, a digital RGB interface used in PCs, to which audio transmission and digital rights management (DRM) functions were added. HDMI was intended mainly for use as a digital video and audio interface for home electronics and AV equipment.
An HDMI (type-A) female connector (photo at left) and male connector (center photo). The compact HDMI cable is easily connected and disconnected, just like a USB cable (photo at right). HDMI cables come in two types: Standard (category 1), denoting those that have passed 74.25 MHz in transmission-speed tests, and High Speed (category 2), denoting those certified for 340 MHz. A High Speed cable is recommended when using high-definition signals such as 1440p.
Since HDMI versions are backward compatible, we can still input and output video and audio if the output side is compatible with version 1.3 or above and the input side with version 1.2a or below. However, if the output device uses functions implemented in version 1.3 or higher, these functions will be canceled on input devices that comply with version 1.2a or earlier.
Formally approved in May 2006, the DisplayPort standard is a new standard released in May 2005 by the Video Electronics Standards Association (VESA) of the United States, an industry organization that establishes standards for PC-related interfaces. As a video interface promoted by VESA, a constituency composed mainly of PC and monitor makers, it is designed to succeed the DVI and D-Sub standards as a PC interface. However, there"s no reason it can"t also be used in AV equipment.
With a maximum transmission speed of 10.8 Gbps, compatibility with resolutions of up to 2560 × 2048 pixels or higher, color depth of 48 bits (16 bits per RGB color), and a maximum refresh rate of 120 Hz (120 fps), its basic video interface specs are close to those of HDMI. However, unlike HDMI, which transmits data for RGB video signals and clock signals separately, it sends all video and audio to the destination device through a serial connection, split into micro-packets called transfer units.
Since DisplayPort is a serial interface like PCI Express that generates a clock from the data instead of using external clock signals, data transmission speeds and functionality are easily improved. In addition, since DisplayPort employs a configuration wherein the LCD monitor is operated directly, it makes it possible to reduce the numbers of components. Another benefit is its ability to transmit signals over distances of up to 15 meters.
In the DisplayPort standard, the output side is defined as the source device and the input side as the sync device. Under this configuration, the source and sync devices communicate with each other, making it possible to automatically adjust transmission to the optimal resolution, color depth, and refresh rate. Audio and video data can be transmitted through a combination of single, double, or quadruple channels called lanes, and two data rates (1.62 Gbps and 2.7 Gbps). The minimum configuration is a single lane at 1.62 Gbps; the maximum is four lanes at 2.7 Gbps each for a total of 10.8 Gbps.
DisplayPort requires no licensing fees other than that for HDCP, making it more attractive and easier for manufacturers to adopt. Progress in mass production will likely lead to price advantages for ordinary users as well. Still, HDMI is clearly the current mainstream digital interface for products like AV equipment and videogame consoles. DisplayPort, even if standardized under the leadership of PC makers, is unlikely to take its place. With growing support for DisplayPort among vendors of graphics chips for use in PC environments and growing numbers of compatible products, including the MacBook, use of DisplayPort is projected to expand.
Let"s discuss video input interfaces, starting with the D-Terminal and component video standards. The video signals themselves are identical for both of these. The video signal is composed of the following three signal types: the Y brightness/synchronization signal; the Pb (Cb) signal for the difference between blue and Y; and the Pr (Cr) signal carrying the difference between red and Y. Altogether, these are referred to as a component video signal. A characteristic of this technology is its ability to input and output high-quality analog video signals by omitting the process of video-signal separation and combination.
A component video port has separate connectors for each of the three video-signal types: A green connector for the Y signal, a blue connector for the Pb (Cb) signal, and a red connector for the Pr (Cr) signal. In most cases, the compatible video formats are 480i, 480p, 720p, and 1080i, with connectors labeled Y, Cb, and Cr compatible with 480i video and connectors labeled Y, Pb, and Pr with higher-quality video formats.
While component video ports offer higher quality and greater benefits than most other types of analog video input, they also entail inconveniences, including more troublesome connections (since they use three connectors) and greater space requirements on devices equipped with such ports. Additionally, they are incapable of transmitting control signals. In Japan, the D-Terminal standard, formulated by the Japan Electronics and Information Technology Industries Association (JEITA, known at the time as the Electronic Industry Association of Japan, or EIAJ), which features its own improvements on these points, has entered widespread use.
A D-Terminal connector combines the three types of component video signals into a single cable and is easier to connect. It also embeds a control signal to identify scanning lines, scanning method, and aspect ratio. (In passing, it"s called a D-Terminal only because its connector is shaped like the letter "D"; the "D" does not mean "digital." Signals flowing through the D-Terminal and the connecting cable are analog.) The table below gives the types of D-Terminals (D1 – 5) and corresponding video formats. While many products feature D5 terminals, which are compatible with 1080p video, this is not specified in the official JEITA standard.
Comparisons of picture quality between component video and D-Terminal standards show that component video, with its three separate connectors, offers higher picture quality, due to structural characteristics of the cable and connector. Many believe this difference becomes even more marked with longer cables.
Let"s consider S-Video and composite video ports. Video consists of a brightness signal and a color signal, combined to create a composite video signal. A composite video port transmits the composite video signal as is; an S-Video port transmits the composite signal separated into a brightness signal and a color signal. Since less processing is needed to combine and separate the brightness and color signals, an S-Video port provides higher picture quality than a composite video port.
On an RCA connector with three single pins in a row, the yellow pin is the composite female connector (photo at left). Most composite cables assume the form of a single cable that splits into three connectors, with the yellow connector used for video and the red and white for stereo audio (center photo). An S-Video female connector (photo at right), which has four pins.
Additionally, there are two types of S-Video ports: S1, which can identify video with aspect ratios of 4:3 and 16:9; and S2, which can identify "letterbox" video with black bands above and below, to display 16:9 aspect-ratio video on 4:3 aspect-ratio monitors. A display device receiving video with a 16:9 aspect ratio or letterbox video performs the appropriate scaling to display the correct aspect ratio.
S-Video and composite ports are capable of handling video up to standard-definition NTSC (480i). They are likely to be phased out gradually in the future, except for applications requiring the connection of older video equipment such as VHS video decks or DV cameras.
Analog video interfaces, including D-Terminal and component video, can be summarized as follows, in descending order of general perception of picture quality: component video, D-Terminal, S-Video, and composite video.
Most such products are adapters, which connect to the PC using USB and feature DVI-D or DVI-I connectors on the output side. These are then connected to LCD monitors. After the user installs a device driver, the PC recognizes the adapter as a monitor adapter. Users can create a multi-monitor environment in Windows by activating the secondary monitor connected to the adapter in Display Properties. In terms of display performance, these adapters are not well suited to uses that require high-speed response; they are associated with slight delays in reflecting mouse or keyboard operations.
A small number of LCD monitors on the market use USB as a video input interface, making it possible to output and display a PC screen through a USB connection between the PC and the LCD display. These, too, are ideal for laptops and netbooks, since they allow users to use laptops connected to large-screen LCD monitors at their office desks or at home, then use the laptops for mobile use when out and about simply by unplugging a single USB cable.