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An on-screen display (OSD) is an image superimposed on a screen picture, commonly used by modern television sets, VCRs, and DVD players to display information such as volume, channel, and time.
In the past, most adjustments on TV sets were performed with analog controls such as potentiometers and switches. This was used more recently also in monochrome portable TVs. After remote controls were invented, digital adjustments became common. They needed an external display, which was LED, LCD, or VFD based. Including this display increased manufacturing costs.
When electronics became more advanced, it became clear that adding some extra devices for an OSD was cheaper than adding a second display device. TV screens had become much bigger and could display much more information than a small second display. OSDs display graphical information superimposed over the picture, which is done by synchronizing the reading from OSD video memory with the TV signal.
Some of the first OSD-equipped televisions were introduced by RCA in the late 1970s, simply displaying the channel number and the time of day at the bottom of the screen. An OSD chip was added to the General instruments (GI) varactor tuning chip set designed in conjunction with RCA and Telefunken. The original OSD was merely to placate users who were faced with a snowy screen during auto tuning. Something the original architecture had not seen as an issue until it was first demonstrated. Once a display had been injected, at least in 1981, a real time clock (RTC) was added to display time and date on video terminals [1] (with greater performance in 1996). [2]
In the 1980s, OSD-capable TVs started to be more common, such as Zenith's "System 3" series. Akai have been credited with the introduction of OSD in VCRs in the 1980s, including the introduction of on screen programming. [3] [4] By the mid-1990s, VCRs with these displays became widely available. This made it possible to reduce the size (and cost) of the VFD or LCD in the VCR. Eventually, as VCRs declined in popularity and prices fell, many manufacturers dropped the internal display completely, relying completely on the on-screen display. All DVD players also use on-screen displays. Many PAL television sets use the internal Teletext decoder's graphics rendering system to further reduce costs.
More recently (as of about 2005), the decline in CRT-based TV sets and rise in LCD/plasma televisions has seen the use and availability of dedicated OSD devices decline, as it is more cost effective to integrate OSD functions inside the main graphics processor. Modern LCD television monitors usually incorporate only two or three integrated circuits. Examples of integrated circuits to perform dedicated OSD are MAX7456 and STV5730. Both operate with NTSC or PAL, mixing with an existing signal or self-generating. Both have slightly different capabilities. This can be done by PIC video superimposer too.[ citation needed ]
Akai produced consumer video cassette recorders (VCR) during the 1980s. The Akai VS-2 was the first VCR with an on-screen display, originally named the Interactive Monitor System. By displaying the information directly on the television screen, this innovation eliminated the need for the user to be physically near the VCR to program recording, read the tape counter, or perform other common features. Within a few years, all competing manufacturers had adopted on-screen display technology in their own products.
Some computer software also uses OSDs, especially support programs for so-called "enhanced keyboards", which often had additional medias like skipping through music tracks and volume adjustment. Their use outside this field is still uncommon. On-screen displays are also used in camcorders, and can display various information both on the viewfinder and on the TV set the camcorder is connected to.
The complexity of graphics offered by such displays has greatly increased over the years, from simple monochrome images to intricate graphical user interfaces.
Several problems exist with regard to on-screen displays. One of them is diagnostics if a television's display system is damaged. Without any external screens, it is almost impossible (without opening the TV) to determine the source of the error. TV accessories that depend heavily on OSDs, such as VCRs or DVD players, are also difficult to configure without the use of a TV. On older VCRs, it was possible to program recording timers without turning on the TV; a modern VCR requires the user to turn on the TV to do so. Usability is generally also decreased with OSDs, as it is necessary to control a multitude of parameters with a few buttons, where earlier, real analog controls with mechanical feedback were available.
The drawbacks of using OSDs do not outweigh their main advantage of being more cost-efficient and allowing to design less separate physical tuning controls, which has led to their widespread use.
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, the beams of which are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms (oscilloscope), pictures, radar targets, or other phenomena. A CRT on a television set is commonly called a picture tube. CRTs have also been used as memory devices, in which case the screen is not intended to be visible to an observer.
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) and some Plasma displays. 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.
A set-top box (STB), also colloquially known as a cable box and historically television decoder, is an information appliance device that generally contains a TV-tuner input and displays output to a television set and an external source of signal, turning the source signal into content in a form that can then be displayed on the television screen or other display device. They are used in cable television, satellite television, and over-the-air television systems as well as other uses.
SCART is a French-originated standard and associated 21-pin connector for connecting audio-visual (AV) equipment. The name SCART comes from Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs, "Radio and Television Receiver Manufacturers' Association", the French organisation that created the connector in the mid-1970s. The related European standard EN 50049 has been then refined and published in 1978 by CENELEC, calling it péritelevision, but it is commonly called by the abbreviation péritel in French.
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.
Home cinema, also called home theaters or theater rooms, are home entertainment audio-visual systems that seek to reproduce a movie theater experience and mood using consumer electronics-grade video and audio equipment that is set up in a room or backyard of a private home. Some studies show films are rated better and generate more intense emotions when watched in a movie theater, however, convenience is a major appeal for home cinemas. In the 1980s, home cinemas typically consisted of a movie pre-recorded on a LaserDisc or VHS tape; a LaserDisc or VHS player; and a heavy, bulky large-screen cathode ray tube TV set, although sometimes CRT projectors were used instead. In the 2000s, technological innovations in sound systems, video player equipment and TV screens and video projectors have changed the equipment used in home cinema set-ups and enabled home users to experience a higher-resolution screen image, improved sound quality and components that offer users more options. The development of Internet-based subscription services means that 2016-era home theatre users do not have to commute to a video rental store as was common in the 1980s and 1990s
A flat-panel display (FPD) is an electronic display device used to enable people to see content in a range of entertainment, consumer electronics, personal computer, and mobile devices, and many types of medical, transportation and industrial equipment. They are far lighter and thinner than traditional cathode ray tube (CRT) television sets and are usually less than 10 centimetres (3.9 in) thick. Flat-panel displays can be divided into two display device categories: volatile and static. Volatile displays require that pixels be periodically electronically refreshed to retain their state. A volatile display only shows an image when it has battery or AC mains power. Static flat-panel displays rely on materials whose color states are bistable, and as such, flat-panel displays retain the text or images on the screen even when the power is off. As of 2016, flat-panel displays have almost completely replaced old CRT displays. In many 2010-era applications, specifically small portable devices such as laptops, mobile phones, smartphones, digital cameras, camcorders, point-and-shoot cameras, and pocket video cameras, any display disadvantages of flat-panels are made up for by portability advantages.
A digital video recorder (DVR) is an electronic device that records video in a digital format to a disk drive, USB flash drive, SD memory card, SSD or other local or networked mass storage device. The term includes set-top boxes with direct to disk recording, portable media players and TV gateways with recording capability, and digital camcorders. Personal computers are often connected to video capture devices and used as DVRs; in such cases the application software used to record video is an integral part of the DVR. Many DVRs are classified as consumer electronic devices; such devices may alternatively be referred to as personal video recorders (PVRs), particularly in Canada. Similar small devices with built-in displays and SSD support may be used for professional film or video production, as these recorders often do not have the limitations that built-in recorders in cameras have, offering wider codec support, the removal of recording time limitations and higher bitrates.
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 and projection displays using fixed picture-element (pixel) arrays.
A television set or television receiver, more commonly called the television, TV, TV set, tube, telly, or tele, is a device that combines a tuner, display, and loudspeakers, for the purpose of viewing and hearing television broadcasting through satellites or cables, or using it as a computer monitor. Introduced in the late 1920s in mechanical form, television sets became a popular consumer product after World War II in electronic form, using cathode ray tube (CRT) technology. The addition of color to broadcast television after 1953 further increased the popularity of television sets in the 1960s, and an outdoor antenna became a common feature of suburban homes. The ubiquitous television set became the display device for the first recorded media in the 1970s, such as Betamax, VHS and later DVD. It has been used as a display device since the first generation of home computers and dedicated video game consoles in the 1980s. By the early 2010s, flat-panel television incorporating liquid-crystal display (LCD) technology, especially LED-backlit LCD technology, largely replaced CRT and other display technologies. Modern flat panel TVs are typically capable of high-definition display and can also play content from a USB device.
Overscan is a behaviour in certain television sets, in which part of the input picture is shown outside of the visible bounds of the screen. It exists because cathode-ray tube (CRT) television sets from the 1930s through to the early 2000s were highly variable in how the video image was positioned within the borders of the screen. It then became common practice to have video signals with black edges around the picture, which the television was meant to discard in this way.
Neuros Technology was a Chicago, Illinois–based company that produced a number of audio and video devices under the brand name Neuros. Founded by Joe Born in 2001 as a division of Digital Innovations, it previously operated under the name Neuros Audio. Like Digital Innovations, Neuros distinguished itself by its use of open-innovation and crowdsourcing techniques to bring products to market, as well as by its prominent use of open-source software and open-source hardware. In its development model, end users were involved throughout the product development process from reviewing initial concepts to beta testing initial product releases.
A combo television unit, or a TV/VCR combo, sometimes known as a televideo, is a television with a VCR, DVD player, or sometimes both, built into a single unit. These converged devices have the advantages of saving space and increasing portability. Such units entered the market during the mid-to-late 1980s when VCRs had become ubiquitous household devices. By this time, the VHS format had become standard; thus the vast majority of TV/VCR combos are VHS-based.
Screen burn-in, image burn-in, or ghost image is a discoloration of areas on an electronic display such as a cathode ray tube (CRT) display or an old computer monitor or television set caused by cumulative non-uniform use of the pixels.
A video reference monitor also called a broadcast reference monitor or just reference monitor, is a specialized display device similar to a television set, used to monitor the output of a video-generating device, such as playout from a video server, IRD, video camera, VCR, or DVD player. It may or may not have professional audio monitoring capability. Unlike a television set, a video monitor has no tuner and, as such, is unable independently to tune into an over-the-air broadcast like a television receiver. One common use of video monitors is in television stations, television studios, production trucks and in outside broadcast vehicles, where broadcast engineers use them for confidence checking of analog signal and digital signals throughout the system. They can also be used for color grading if calibrated, during post-production.
A universal remote is a remote control that can be programmed to operate various brands of one or more types of consumer electronics devices. Low-end universal remotes can only control a set number of devices determined by their manufacturer, while mid- and high-end universal remotes allow the user to program in new control codes to the remote. Many remotes sold with various electronics include universal remote capabilities for other types of devices, which allows the remote to control other devices beyond the device it came with. For example, a VCR remote may be programmed to operate various brands of televisions.
Laser color television, or laser color video display utilizes two or more individually modulated optical (laser) rays of different colors to produce a combined spot that is scanned and projected across the image plane by a polygon-mirror system or less effectively by optoelectronic means to produce a color-television display. The systems work either by scanning the entire picture a dot at a time and modulating the laser directly at high frequency, much like the electron beams in a cathode ray tube, or by optically spreading and then modulating the laser and scanning a line at a time, the line itself being modulated in much the same way as with digital light processing (DLP).
A LED-backlit LCD is a liquid-crystal display that uses LEDs for backlighting instead of traditional cold cathode fluorescent (CCFL) backlighting. LED-backlit displays use the same TFT LCD technologies as CCFL-backlit LCDs, but offer a variety of advantages over them.
A videocassette recorder (VCR) or video recorder is an electromechanical device that records analog audio and analog video from broadcast television or other source on a removable, magnetic tape videocassette, and can play back the recording. Use of a VCR to record a television program to play back at a more convenient time is commonly referred to as timeshifting. VCRs can also play back prerecorded tapes. In the 1980s and 1990s, prerecorded videotapes were widely available for purchase and rental, and blank tapes were sold to make recordings.
A text display is an electronic alphanumeric display device that is mainly or only capable of showing text, or extremely limited graphic characters. This includes electromechanical split-flap displays, vane displays, and flip-disc displays; all-electronic liquid-crystal displays, incandescent eggcrate displays, LED displays, and vacuum fluorescent displays; and even electric nixie tubes.