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87-511: The company's initial product amounted to a screensaver that displayed news and other information, delivered live over the Internet. The PointCast Network used push technology , which was a new concept at the time, and received enormous press coverage when it launched in beta form on February 13, 1996. The product did not perform as well as expected, often believed to be because its traffic burdened corporate networks with excessive bandwidth use, and

174-542: A University of Illinois ECE PhD (in plasma display research) and staff scientist working at CERL (home of the PLATO System ), co-founded Plasmaco with Stephen Globus and IBM plant manager James Kehoe, and bought the plant from IBM for US$ 50,000. Weber stayed in Urbana as CTO until 1990, then moved to upstate New York to work at Plasmaco. In 1992, Fujitsu introduced the world's first 21-inch (53 cm) full-color display. It

261-495: A password before permitting the user to resume work. This is a basic security measure against another person accessing the machine while the user is absent. Some screensavers activate a useful background task, such as a virus scan or a volunteer computing application (such as the SETI@home project). This allows applications to use resources only when the computer would be otherwise idle. The Ken Burns panning and zooming effect

348-479: A seven-segment display for use in adding machines . They became popular for their bright orange luminous look and found nearly ubiquitous use throughout the late 1970s and into the 1990s in cash registers , calculators , pinball machines , aircraft avionics such as radios , navigational instruments , and stormscopes ; test equipment such as frequency counters and multimeters ; and generally anything that previously used nixie tube or numitron displays with

435-405: A shadow mask CRT or color LCD. Plasma panels use pulse-width modulation (PWM) to control brightness: by varying the pulses of current flowing through the different cells thousands of times per second, the control system can increase or decrease the intensity of each subpixel color to create billions of different combinations of red, green and blue. In this way, the control system can produce most of

522-474: A virus or malware to install itself. Modern versions of Windows can read tags left by applications such as Internet Explorer and verify the publisher of the file , presenting a confirmation to the user. On August 5, 2006, the BBC reported that "free screensavers" and "screensavers" respectively were the first and third most likely search terms to return links to malware, the second being BearShare . By launching

609-501: A Hungarian engineer, described a proposed flat-panel plasma display system in a 1936 paper. The first practical plasma video display was co-invented in 1964 at the University of Illinois at Urbana–Champaign by Donald Bitzer , H. Gene Slottow , and graduate student Robert Willson for the PLATO computer system . The goal was to create a display that had inherent memory to reduce the cost of

696-416: A LED backlight. Older CCFL backlights for LCD panels used quite a bit more power, and older plasma TVs used quite a bit more power than recent models. Plasma displays do not work as well at high altitudes above 6,500 feet (2,000 meters) due to pressure differential between the gases inside the screen and the air pressure at altitude. It may cause a buzzing noise. Manufacturers rate their screens to indicate

783-480: A San Diego company founded and backed by Idealab , and the PointCast network was shut down the next year. Launchpad's eWallet product was combined with the existing PointCast technology to create EntryPoint, which had a free desktop toolbar and offered customized news, stocks and sports feeds. EntryPoint merged with Internet Financial Network in 2000 forming Infogate, continuing the same free service until switching to

870-478: A basic layer of security by requiring a password to re-access the device. Some screensaver programs also use otherwise-idle computer resources to do useful work, such as processing for volunteer computing projects. As well as computers, modern television operating systems, media players, and other digital entertainment systems may include optional screensavers. Before the advent of LCD screens, most computer screens were based on cathode-ray tubes (CRTs). When

957-402: A cell, creating a voltage difference between front and back. Some of the atoms in the gas of a cell then lose electrons and become ionized , which creates an electrically conducting plasma of atoms, free electrons, and ions. The collisions of the flowing electrons in the plasma with the inert gas atoms leads to light emission; such light-emitting plasmas are known as glow discharges . In

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1044-535: A consortium of telephone companies and Microsoft put together a project designed to promote use of DSL in preference to cable modems. The project was dubbed "Newnet" and the plan was to use PointCast's software as a portal for the service. The consortium planned to buy PointCast for $ 100 million as part of the deal. The deal was signed in December 1998 with the intent of launching the service in April 1999. Due to delays in

1131-462: A fee-based co-branded model, partnering with news outlets such as USA Today and CNN . Infogate was sold to AOL Time Warner in March 2003. Infogate senior executives Cliff Boro, Vidar Vignisson, and Tom Broadhead formed CVT Ventures, LLC, a venture-development group dedicated to accelerating technology startups. Screensaver A screensaver (or screen saver ) is a computer program that blanks

1218-599: A full-off display. Manufacturers can further artificially improve the reported contrast ratio by increasing the contrast and brightness settings to achieve the highest test values. However, a contrast ratio generated by this method is misleading, as content would be essentially unwatchable at such settings. Each cell on a plasma display must be precharged before it is lit, otherwise the cell would not respond quickly enough. Precharging normally increases power consumption, so energy recovery mechanisms may be in place to avoid an increase in power consumption. This precharging means

1305-443: A high digit-count. These displays were eventually replaced by LEDs because of their low current-draw and module-flexibility, but are still found in some applications where their high brightness is desired, such as pinball machines and avionics. In 1983, IBM introduced a 19-inch (48 cm) orange-on-black monochrome display (Model 3290 Information Panel) which was able to show up to four simultaneous IBM 3270 terminal sessions. By

1392-410: A long enough period has passed (with the display either off or on). Plasma manufacturers have tried various ways of reducing burn-in such as using gray pillarboxes, pixel orbiters and image washing routines. Recent models have a pixel orbiter that moves the entire picture slower than is noticeable to the human eye, which reduces the effect of burn-in but does not prevent it. None to date have eliminated

1479-463: A monochrome plasma panel, the gas is mostly neon, and the color is the characteristic orange of a neon-filled lamp (or sign ). Once a glow discharge has been initiated in a cell, it can be maintained by applying a low-level voltage between all the horizontal and vertical electrodes–even after the ionizing voltage is removed. To erase a cell all voltage is removed from a pair of electrodes. This type of panel has inherent memory. A small amount of nitrogen

1566-547: A phosphor molecule, it momentarily raises the energy level of an outer orbit electron in the phosphor molecule, moving the electron from a stable to an unstable state; the electron then sheds the excess energy as a photon at a lower energy level than UV light; the lower energy photons are mostly in the infrared range but about 40% are in the visible light range. Thus the input energy is converted to mostly infrared but also as visible light. The screen heats up to between 30 and 41 °C (86 and 106 °F) during operation. Depending on

1653-457: A slight edge in picture quality and a price advantage for sets at the critical 42" size and larger. By late 2006, several vendors were offering 42" LCDs, albeit at a premium price, encroaching upon plasma's only stronghold. More decisively, LCDs offered higher resolutions and true 1080p support, while plasmas were stuck at 720p , which made up for the price difference. In late 2006, analysts noted that LCDs had overtaken plasmas, particularly in

1740-413: Is about 6 cm (2.4 in) thick, generally allowing the device's total thickness (including electronics) to be less than 10 cm (3.9 in). Power consumption varies greatly with picture content, with bright scenes drawing significantly more power than darker ones – this is also true for CRTs as well as modern LCDs where LED backlight brightness is adjusted dynamically. The plasma that illuminates

1827-422: Is added to the neon to increase hysteresis . Plasma panels may be built without nitrogen gas, using xenon, neon, argon, and helium instead with mercury being used in some early displays. In color panels, the back of each cell is coated with a phosphor . The ultraviolet photons emitted by the plasma excite these phosphors, which give off visible light with colors determined by the phosphor materials. This aspect

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1914-406: Is comparable to fluorescent lamps and to the neon signs that use colored phosphors. Every pixel is made up of three separate subpixel cells, each with different colored phosphors. One subpixel has a red light phosphor, one subpixel has a green light phosphor and one subpixel has a blue light phosphor. These colors blend together to create the overall color of the pixel, the same as a triad of

2001-405: Is idle lasting a few minutes (different times depending on the model), stored in the system ROM of the computer. Monitors running screensavers consume the same amount of power as when running normally, which can be anywhere from a few watts for small LCD monitors to several hundred for large plasma displays. Most modern computers can be set to switch the monitor into a lower power mode, blanking

2088-526: Is normally necessary because plasma displays have to be baked during manufacture to dry the rare-earth phosphors after they are applied to the display. However, high strain point glass may be less scratch resistant. Until the early 2000s, plasma displays were the most popular choice for HDTV flat-panel display as they had many benefits over LCDs. Beyond plasma's deeper blacks, increased contrast, faster response time, greater color spectrum, and wider viewing angle; they were also much bigger than LCDs, and it

2175-548: Is not always noticeable. High-end computer monitors have technologies to try to compensate for the uniformity problem. Contrast ratio is the difference between the brightest and darkest parts of an image, measured in discrete steps, at any given moment. Generally, the higher the contrast ratio, the more realistic the image is (though the "realism" of an image depends on many factors including color accuracy, luminance linearity, and spatial linearity). Contrast ratios for plasma displays are often advertised as high as 5,000,000:1. On

2262-493: Is now something of a misnomer – the best way to save the screen and also save electricity consumed by screen would simply be to have the computer turn off the monitor. Screensavers displaying complex 3D graphics might even add to overall power draw. After Dark was an early screensaver for the Macintosh platform, and later PC/Windows, which prominently featured whimsical designs such as "flying toasters". Perhaps in response to

2349-404: Is sometimes confused with screen burn-in damage. In this mode, when a group of pixels are run at high brightness (when displaying white, for example) for an extended period, a charge build-up in the pixel structure occurs and a ghost image can be seen. However, unlike burn-in, this charge build-up is transient and self-corrects after the image condition that caused the effect has been removed and

2436-434: Is sometimes used to bring the image to life. Decades before the first computers using this technology were invented, Robert A. Heinlein gave an example of how they might be used in his novel Stranger in a Strange Land (1961): Opposite his chair was a stereovision tank disguised as an aquarium; he switched it on, guppies and tetras gave way to the face of the well-known Winchell Augustus Greaves. The first screensaver

2523-539: Is used for promotion , especially to build buzz for "event-based" products such as feature films . The screensaver is also a creative outlet for computer programmers. The Unix -based screensaver XScreenSaver collects the display effects of other Unix screensavers, which are termed "display hacks" in the Jargon File tradition of US computer science academics. It also collects forms of computer graphics effects called demo effects , such as were originally produced by

2610-406: The .saver file extension. Internally, the screensaver must define a class that is subclass of ScreenSaverView . The new class must be assigned as NSPrincipalClass in the xcode project, so that when the screensaver is launched by the system, this class gets instantiated. As one of the first screensavers appeared in 8-bit Atari computers, forcing systemic color changes when the computer

2697-550: The C or C++ programming languages, along with Graphics Device Interface (GDI), such as OpenGL ("Open Graphics Library", which works on many, if not most, platforms capable of 3D rendering ), or alternatives such as Microsoft DirectX (which is limited to Microsoft platforms, mainly Microsoft Windows and the Microsoft Xbox ), to craft their final products. Several OS X screensavers are created and designed using Quartz Composer . The screensaver interfaces indirectly with

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2784-409: The demoscene . On older versions of Microsoft Windows the native screensaver format had the potential to install a virus when run (as a screen saver was just an ordinary application with a different extension). When any file with the file suffix ".scr" was opened, for example from an email attachment , Windows would execute the .scr (screensaver) file automatically: this had the potential to allow

2871-500: The video scaling processor and the upscaling and downscaling algorithms used by each display manufacturer. Early plasma televisions were enhanced-definition (ED) with a native resolution of 840×480 (discontinued) or 852×480 and down-scaled their incoming high-definition video signals to match their native display resolutions. The following ED resolutions were common prior to the introduction of HD displays, but have long been phased out in favor of HD displays, as well as because

2958-536: The " WM_SYSCOMMAND " message with the " SC_SCREENSAVE " argument. If the program calls in response the standard system function ( DefWindowProc ), the screensaver defined in the control panel screen runs. A Windows screensaver is a regular Portable Executable (PE) with the .scr file extension. This enables malware authors to add ".scr" to the name of any win32 executable file, and thereby increase likelihood that users of Microsoft Windows will run it unintentionally. In addition, this program should support

3045-518: The "bubbles" screensaver executable through the bubbles.scr /p65552 command-line parameter, it runs as desktop wallpaper , the bubbles are smaller, and there are more bubbles on screen. The user must use the Task Manager to stop the screensaver. Plasma display A plasma display panel is a type of flat-panel display that uses small cells containing plasma : ionized gas that responds to electric fields . Plasma televisions were

3132-519: The 1977 Atari VCS/2600 gaming console such as Combat and Breakout , included color cycling in order to prevent burn-in of game images into 1970s-era televisions. In addition, the first model of the TI-30 calculator from 1976 featured a screensaver, which consisted of a decimal point running across the display after 30 seconds of inactivity. This was chiefly used to save battery power, as the TI-30 LED display

3219-436: The 40-inch (100 cm) and above segment where plasma had previously gained market share. Another industry trend was the consolidation of plasma display manufacturers, with around 50 brands available but only five manufacturers. In the first quarter of 2008, a comparison of worldwide TV sales broke down to 22.1 million for direct-view CRT, 21.1 million for LCD, 2.8 million for plasma, and 0.1 million for rear projection. When

3306-551: The altitude parameters. For those who wish to listen to AM radio , or are amateur radio operators (hams) or shortwave listeners (SWL), the radio frequency interference (RFI) from these devices can be irritating or disabling. In their heyday, they were less expensive for the buyer per square inch than LCD, particularly when considering equivalent performance. Plasma displays have wider viewing angles than those of LCD; images do not suffer from degradation at less than straight ahead angles like LCDs. LCDs using IPS technology have

3393-545: The case of ATMs) visible even when the display changes while the machine is in use. Blanking the screen is not a valid option as the machine can be perceived as out of service. In these applications, burn-in can be prevented by shifting the position of the display contents every few seconds, or by having a number of different images that are changed regularly. Later CRTs were much less susceptible to burn-in than older models due to improvements in phosphor coatings, and because modern computer images are generally lower contrast than

3480-541: The cells cannot achieve a true black, whereas an LED backlit LCD panel can actually turn off parts of the backlight, in "spots" or "patches" (this technique, however, does not prevent the large accumulated passive light of adjacent lamps, and the reflection media, from returning values from within the panel). Some manufacturers have reduced the precharge and the associated background glow, to the point where black levels on modern plasmas are starting to become close to some high-end CRTs Sony and Mitsubishi produced ten years before

3567-423: The cells, along the rear glass plate, and can be opaque. The transparent display electrodes are mounted in front of the cell, along the front glass plate. As can be seen in the illustration, the electrodes are covered by an insulating protective layer. A magnesium oxide layer may be present to protect the dielectric layer and to emit secondary electrons. Control circuitry charges the electrodes that cross paths at

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3654-426: The comparable plasma displays. With an LCD, black pixels are generated by a light polarization method; many panels are unable to completely block the underlying backlight. More recent LCD panels using LED illumination can automatically reduce the backlighting on darker scenes, though this method cannot be used in high-contrast scenes, leaving some light showing from black parts of an image with bright parts, such as (at

3741-400: The cryptocurrency bitcoin . Modern graphics technologies such as 3D computer graphics have allowed a wide variety of screensavers to be made. Screensavers with realistic 3D environments can be programmed and run on modern computers. Screensavers are usually designed and coded using a variety of programming languages as well as graphics interfaces. Typically the authors of screensavers use

3828-455: The demise of PointCast. When PointCast first started, Yahoo offered little more than a hierarchical structure on the Internet (broken down by subject much like DMOZ ), but was soon to introduce the portal which was customizable and offered a much more convenient way to read the news. At its height in January 1997, News Corporation made an offer of $ 450 million to purchase the company. However,

3915-485: The display module), have a wide color gamut , and can be produced in fairly large sizes—up to 3.8 metres (150 in) diagonally. They had a very low luminance "dark-room" black level compared with the lighter grey of the unilluminated parts of an LCD screen. (As plasma panels are locally lit and do not require a back light, blacks are blacker on plasma and grayer on LCDs.) LED-backlit LCD televisions have been developed to reduce this distinction. The display panel itself

4002-508: The display screen or fills it with moving images or patterns when the computer has been idle for a designated time. The original purpose of screensavers was to prevent phosphor burn-in on CRT or plasma computer monitors (hence the name). Though most modern monitors are not susceptible to this issue (with the notable exception of OLED technology, which has individual pixels vulnerable to burnout), screensaver programs are still used for other purposes. Screensavers are often set up to offer

4089-630: The end of the decade, orange monochrome plasma displays were used in a number of high-end AC -powered portable computers , such as the Ericsson Portable PC (the first use of such a display in 1985), the Compaq Portable 386 (1987) and the IBM P75 (1990). Plasma displays had a better contrast ratio, viewability angle, and less motion blur than the LCDs that were available at the time, and were used until

4176-727: The extreme) a solid black screen with one fine intense bright line. This is called a "halo" effect which has been minimized on newer LED-backlit LCDs with local dimming. Edgelit models cannot compete with this as the light is reflected via a light guide to distribute the light behind the panel. Plasma displays are capable of producing deeper blacks than LCD allowing for a superior contrast ratio. Earlier generation displays (circa 2006 and prior) had phosphors that lost luminosity over time, resulting in gradual decline of absolute image brightness. Newer models have advertised lifespans exceeding 100,000 hours (11 years), far longer than older CRTs . Image burn-in occurs on CRTs and plasma panels when

4263-700: The first 42-inch (107 cm) plasma display panel; it had 852×480 resolution and was progressively scanned. Two years later, Philips introduced at CES and CeBIT the first large commercially available flat-panel TV, using the Fujitsu panels. Philips had plans to sell it for 70,000 french francs. It was released as the Philips 42PW9962. It was available at four Sears locations in the US for $ 14,999, including in-home installation. Pioneer and Fujitsu also began selling plasma televisions that year, and other manufacturers followed. By

4350-909: The first large (over 32 inches diagonal) flat-panel displays to be released to the public. Until about 2007, plasma displays were commonly used in large televisions. By 2013, they had lost nearly all market share due to competition from low-cost liquid crystal displays ( LCD )s. Manufacturing of plasma displays for the United States retail market ended in 2014, and manufacturing for the Chinese market ended in 2016. Plasma displays are obsolete, having been superseded in most if not all aspects by OLED displays. Competing display technologies include cathode-ray tube (CRT), organic light-emitting diode (OLED), CRT projectors , AMLCD , Digital Light Processing DLP, SED-tv , LED display , field emission display (FED), and quantum dot display (QLED). Kálmán Tihanyi ,

4437-596: The following command line parameters: With no parameter – shows the Settings dialog box or do nothing. Runs the screensaver. Previews the screensaver as child of window. <HWND> (presented as unsigned decimal number ) is an identifier ( handle ) of the window in which the preview should appear. Shows the Settings dialog box, modal to the foreground window. Changes password, modal to window <HWND> . Windows 95 screensavers must handle it. Under macOS, screensavers are regular macOS application bundles with

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4524-457: The gas in the cells forms a plasma . With flow of electricity ( electrons ), some of the electrons strike mercury particles as the electrons move through the plasma, momentarily increasing the energy level of the atom until the excess energy is shed. Mercury sheds the energy as ultraviolet (UV) photons. The UV photons then strike phosphor that is painted on the inside of the cell. When the UV photon strikes

4611-417: The images on the screen during periods of user inactivity. For CRTs used in public, such as ATMs and railway ticketing machines, the risk of burn-in is especially high because a stand-by display is shown whenever the machine is not in use. Older machines designed without burn-in problems taken into consideration often display evidence of screen damage, with images or text such as "Please insert your card" (in

4698-462: The introduction of active-matrix color LCD displays in 1992. Due to heavy competition from monochrome LCDs used in laptops and the high costs of plasma display technology, in 1987 IBM planned to shut down its factory in Kingston, New York, the largest plasma plant in the world, in favor of manufacturing mainframe computers , which would have left development to Japanese companies. Dr. Larry F. Weber ,

4785-523: The lightest whites are simultaneously measured, yielding the most accurate "real-world" ratings. In contrast, a full-on-full-off test measures the ratio using a pure black screen and a pure white screen, which gives higher values but does not represent a typical viewing scenario. Some displays, using many different technologies, have some "leakage" of light, through either optical or electronic means, from lit pixels to adjacent pixels so that dark pixels that are near bright ones appear less dark than they do during

4872-606: The new Z-29 computer terminal 's features, telling InfoWorld that it "blanks out the display after 15 minutes of nonactivity, preventing burned-in character displays." The first screensaver that allowed users to change the activating time was released on Apple 's Lisa , in 1983. The Atari 400 and 800's screens would also go through random screensaver-like color changes if they were left inactive for about 8 minutes. Normal users had no control over this, though programs did. These computers, released in 1979, are technically earlier "screen savers". Prior to these computers, games for

4959-527: The offer was withdrawn in March. While there were rumors that it was withdrawn due to issues with the price and revenue projections, James Murdoch said it was due to PointCast's inaction. Shortly after not accepting the purchase offer, the board of directors decided to replace Christopher Hassett as the CEO . Some reasons included turning down the recent purchase offer, software performance problems (using too much corporate bandwidth) and declining market share (lost to

5046-440: The operating system to cause the physical display screen to be overlaid with one or more graphic "scenes". The screensaver typically terminates after receiving a message from the operating system that a key has been pressed or the mouse has been moved. If the system detects inactivity lasting longer than the time specified in the control panel , check if the active program is a simple program (and not another screensaver) by sending

5133-970: The overall pixel count in ED displays is lower than the pixel count on SD PAL displays (852×480 vs 720×576, respectively). Early high-definition (HD) plasma displays had a resolution of 1024x1024 and were alternate lighting of surfaces (ALiS) panels made by Fujitsu and Hitachi . These were interlaced displays, with non-square pixels. Later HDTV plasma televisions usually have a resolution of 1,024×768 found on many 42 inch plasma screens, 1280×768 and 1,366×768 found on 50 in, 60 in, and 65 in plasma screens, or 1920×1080 found on plasma screen sizes from 42 inch to 103 inch. These displays are usually progressive displays, with non-square pixels, and will up-scale and de-interlace their incoming standard-definition signals to match their native display resolutions. 1024×768 resolution requires that 720p content be downscaled in one direction and upscaled in

5220-445: The phosphors used, different colors of visible light can be achieved. Each pixel in a plasma display is made up of three cells comprising the primary colors of visible light. Varying the voltage of the signals to the cells thus allows different perceived colors. The long electrodes are stripes of electrically conducting material that also lies between the glass plates in front of and behind the cells. The "address electrodes" sit behind

5307-488: The plasma displays' relatively large screen size and 1 inch thickness made them suitable for high-profile placement in lobbies and stock exchanges. Burroughs Corporation , a maker of adding machines and computers, developed the Panaplex display in the early 1970s. The Panaplex display, generically referred to as a gas-discharge or gas-plasma display, uses the same technology as later plasma video displays, but began life as

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5394-409: The power (around 500–700 watts) of a "home" setting of less extreme brightness. The lifetime of the latest generation of plasma displays is estimated at 100,000 hours (11 years) of actual display time, or 27 years at 10 hours per day. This is the estimated time over which maximum picture brightness degrades to half the original value. Plasma screens are made out of glass, which may result in glare on

5481-415: The problem and all plasma manufacturers continue to exclude burn-in from their warranties. Fixed-pixel displays such as plasma TVs scale the video image of each incoming signal to the native resolution of the display panel. The most common native resolutions for plasma display panels are 852×480 ( EDTV ), 1,366×768 and 1920×1080 ( HDTV ). As a result, picture quality varies depending on the performance of

5568-500: The project, Dorman resigned as CEO in March 1999. Two weeks later, PointCast was informed that their planned acquisition had been scrapped. In the reorganization that followed, 75 of the 220 employees were let go in an effort to reduce costs. A number of bids were made to buy the company, including two from former CEO Christopher Hassett, which were rejected. Instead, they sold out for about $ 7 million in May 1999 to Launchpad Technologies, Inc.,

5655-412: The sales figures for the 2007 Christmas season were finally tallied, analysts were surprised to find that not only had LCD outsold plasma, but CRTs as well, during the same period. This development drove competing large-screen systems from the market almost overnight. The February 2009 announcement that Pioneer Electronics was ending production of plasma screens was widely considered the tipping point in

5742-539: The same image is displayed on a CRT screen for long periods, the properties of the exposed areas of the phosphor coating on the inside of the screen gradually and permanently change, eventually leading to a darkened shadow or "ghost" image on the screen, called a screen burn-in . Cathode-ray tube televisions , oscilloscopes and other devices that use CRTs are all susceptible to phosphor burn-in , as are plasma displays to some extent. Screen-saver programs were designed to help avoid these effects by automatically changing

5829-473: The same picture is displayed for long periods. This causes the phosphors to overheat, losing some of their luminosity and producing a "shadow" image that is visible with the power off. Burn-in is especially a problem on plasma panels because they run hotter than CRTs. Early plasma televisions were plagued by burn-in, making it impossible to use video games or anything else that displayed static images. Plasma displays also exhibit another image retention issue which

5916-439: The screen altogether. A power-saving mode for monitors is usually part of the power management options supported in modern operating systems , though it must also be supported by the computer hardware and monitor itself. Using a screensaver with a flat panel or TFT LCD screen not powering down the screen can actually decrease the lifetime of the display, since the fluorescent backlight remains lit and ages faster than it would if

6003-409: The screen can reach a temperature of at least 1,200 °C (2,190 °F). Typical power consumption is 400 watts for a 127 cm (50 in) screen. Most screens are set to "vivid" mode by default in the factory (which maximizes the brightness and raises the contrast so the image on the screen looks good under the extremely bright lights that are common in big box stores), which draws at least twice

6090-851: The screen from nearby light sources. Plasma display panels cannot be economically manufactured in screen sizes smaller than 82 centimetres (32 in). Although a few companies have been able to make plasma enhanced-definition televisions (EDTV) this small, even fewer have made 32 inch plasma HDTVs . With the trend toward large-screen television technology , the 32 inch screen size was rapidly disappearing by mid-2009. Though considered bulky and thick compared with their LCD counterparts, some sets such as Panasonic 's Z1 and Samsung 's B860 series are as slim as 2.5 cm (1 in) thick making them comparable to LCDs in this respect. Plasma displays are generally heavier than LCD and may require more careful handling, such as being kept upright. Plasma displays use more electrical power, on average, than an LCD TV using

6177-464: The screen is turned off and on frequently. As fluorescent tubes age they grow progressively dimmer, and they can be expensive or difficult to replace. A typical LCD screen loses about 50% of its brightness during a normal product lifetime . In most cases, the tube is an integral part of the LCD and the entire assembly needs to be replaced. This is not true of LED backlit displays. Thus the term "screen saver"

6264-486: The shipments of plasma TVs reached 18.2 million units globally. Since that time, shipments of plasma TVs have declined substantially. This decline has been attributed to the competition from liquid crystal (LCD) televisions, whose prices have fallen more rapidly than those of the plasma TVs. In late 2013, Panasonic announced that they would stop producing plasma TVs from March 2014 onwards. In 2014, LG and Samsung discontinued plasma TV production as well, effectively killing

6351-755: The stark green- or white-on-black text and graphics of earlier machines. LCD computer monitors, including the display panels used in laptop computers, are not susceptible to burn-in because the image is not directly produced by phosphors (although they can suffer from a less extreme and usually non-permanent form of image persistence ). While modern screens are not susceptible to the issues discussed above, screensavers are still used. Primarily these are for decorative/entertainment purposes, or for password protection. They usually feature moving images or patterns and sometimes sound effects. As screensavers are generally expected to activate when users are away from their machines, many screensavers can be configured to ask users for

6438-448: The surface, this is a significant advantage of plasma over most other current display technologies, a notable exception being organic light-emitting diode . Although there are no industry-wide guidelines for reporting contrast ratio, most manufacturers follow either the ANSI standard or perform a full-on-full-off test. The ANSI standard uses a checkered test pattern whereby the darkest blacks and

6525-662: The technology's history as well. Screen sizes have increased since the introduction of plasma displays. The largest plasma video display in the world at the 2008 Consumer Electronics Show in Las Vegas , Nevada , was a 150-inch (380 cm) unit manufactured by Matsushita Electric Industrial (Panasonic) standing 6 ft (180 cm) tall by 11 ft (340 cm) wide. At the 2010 Consumer Electronics Show in Las Vegas, Panasonic introduced their 152" 2160p 3D plasma. In 2010, Panasonic shipped 19.1 million plasma TV panels. In 2010,

6612-402: The technology, probably because of lowering demand. A panel of a plasma display typically comprises millions of tiny compartments in between two panels of glass. These compartments, or "bulbs" or "cells", hold a mixture of noble gases and a minuscule amount of another gas (e.g., mercury vapor). Just as in the fluorescent lamps over an office desk, when a high voltage is applied across the cell,

6699-425: The terminals. The original neon orange monochrome Digivue display panels built by glass producer Owens-Illinois were very popular in the early 1970s because they were rugged and needed neither memory nor circuitry to refresh the images. A long period of sales decline occurred in the late 1970s because semiconductor memory made CRT displays cheaper than the $ 2500 USD 512 × 512 PLATO plasma displays. Nevertheless,

6786-440: The then-emerging Web portal sites.) After five months, David Dorman was chosen as the new CEO. In an effort to raise more capital, Dorman planned to take the company public. A filing was made in May 1998 with a valuation of $ 250 million. This plan was abandoned after two months in favor of looking for a company with whom to partner or be acquired. In August 1998, PointCast found such a partner. In order to compete with @Home ,

6873-463: The visible colors. Plasma displays use the same phosphors as CRTs, which accounts for the extremely accurate color reproduction when viewing television or computer video images (which use an RGB color system designed for CRT displays). To produce light, the cells need to be driven at a relatively high voltage (~300 volts) and the pressure of the gases inside the cell needs to be low (~500 torr). Plasma displays are bright (1,000  lux or higher for

6960-635: The widest angles, but they do not equal the range of plasma primarily due to "IPS glow", a generally whitish haze that appears due to the nature of the IPS pixel design. Plasma displays have less visible motion blur , thanks in large part to very high refresh rates and a faster response time , contributing to superior performance when displaying content with significant amounts of rapid motion such as auto racing, hockey, baseball, etc. Plasma displays have superior uniformity to LCD panel backlights, which nearly always produce uneven brightness levels, although this

7047-540: The workplace environment in which they are often viewed, many screensavers continue this legacy of whimsy by populating the idle monitor with animals or fish, video games , and visual expressions of mathematics equations (through the use of fractals , Fourier transforms or other means) as in the Electric Sheep screensaver. At least one screensaver, Johnny Castaway , told a humorous animated story over many months. The ability of screensavers to divert and entertain

7134-455: The year 2000 prices had dropped to $ 10,000. In the year 2000, the first 60-inch plasma display was developed by Plasmaco. Panasonic was also reported to have developed a process to make plasma displays using ordinary window glass instead of the much more expensive "high strain point" glass. High strain point glass is made similarly to conventional float glass, but it is more heat resistant, deforming at higher temperatures. High strain point glass

7221-503: Was allegedly written for the original IBM PC by John Socha , best known for creating Norton Commander ; he also coined the term screen saver . The screensaver, named scrnsave , was published in the December 1983 issue of the Softalk magazine. It simply blanked the screen after three minutes of inactivity (an interval which could be changed by recompiling the program). By 1983 a Zenith Data Systems executive included "screen-saver" among

7308-428: Was banned in many places. It demanded more bandwidth than the home dial-up Internet connections of the day could provide, and people objected to the large number of advertisements that were pushed over the service as well. PointCast offered corporations a proxy server that would dramatically reduce the bandwidth used, but even this didn't help save the company. The increasing popularity of "portal websites" also accelerated

7395-503: Was based on technology created at the University of Illinois at Urbana–Champaign and NHK Science & Technology Research Laboratories . In 1994, Weber demonstrated a color plasma display at an industry convention in San Jose. Panasonic Corporation began a joint development project with Plasmaco, which led in 1996 to the purchase of Plasmaco, its color AC technology, and its American factory for US$ 26 million. In 1995, Fujitsu introduced

7482-470: Was believed that LCDs were suited only to smaller sized televisions. Plasma had overtaken rear-projection systems in 2005. However, improvements in LCD fabrication narrowed the technological gap. The increased size, lower weight, falling prices, and often lower electrical power consumption of LCDs made them competitive with plasma television sets. In 2006, LCD prices started to fall rapidly and their screen sizes increased, although plasma televisions maintained

7569-448: Was more power intensive than later LCD models. These are examples of screensavers in ROM or the firmware of a computer. Android 4.2 introduced "daydreams", screensavers that activate while the device is docked or charging. In 2015 the screensaver "Event Listeners" of van den Dorpel became the first work of art that was purchased by a museum ( Museum of Applied Arts, Vienna ) using

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