Plasma display

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A 103" plasma display panel by Panasonic, on display in August 2009.

A plasma display panel (PDP) is a type of flat panel display common to large TV displays 30 inches (76 cm) or larger. They are called "plasma" displays because the technology utilizes small cells containing electricallycharged ionized gases, or what are in essence chambers more commonly known as fluorescent lamps.

 

 

General characteristics[edit]

Plasma displays are bright (1,000 lux or higher for the 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 at least in the early history of the competing technologies (in the early history of plasma panels the blacks were blacker on plasmas and greyer on LCDs).[1] LED-backlit LCD televisions have been developed to reduce this distinction. The display panel itself 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 the screen can reach a temperature of at least 1200 °C (2200 °F). Typical power consumption is 400 watts for a 127 cm (50 in) screen. 200 to 310 watts for a 127 cm (50 in) display when set to cinema mode.[citation needed] Most screens are set to "shop" mode by default, which draws at least twice the power (around 500–700 watts) of a "home" setting of less extreme brightness.[2] Panasonic has greatly reduced power consumption ("1/3 of 2007 models").[3] Panasonic states that PDPs will consume only half the power of their previous series of plasma sets to achieve the same overall brightness for a given display size. The lifetime of the latest generation of plasma displays is estimated at 100,000 hours 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.[4]

This causes glare from reflected objects in the viewing area. Companies such as Panasonic coat their newer plasma screens with an anti-glare filter material.[citation needed] Currently, plasma 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 is rapidly disappearing. 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.

Competing display technologies include cathode ray tube (CRT), organic light-emitting diode (OLED), AMLCD, Digital Light Processing DLP, SED-tv,LED display, field emission display (FED), and quantum dot display (QLED).

Plasma display advantages and disadvantages[edit]

Further information: Comparison CRT, LCD, Plasma

Advantages[edit]

  • Picture quality
    • Capable of producing deeper blacks allowing for superior contrast ratio[5][6][7]
    • Wider viewing angles than those of LCD; images do not suffer from degradation at high angles like LCDs[5][6]
    • 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.[5][6][8][9]

Disadvantages[edit]

  • Earlier generation displays were more susceptible to screen burn-in and image retention, 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.[10]
  • Due to the bistable nature of the colour and intensity generating method, some people will notice that plasma displays have a shimmering or flickering effect with a number of hues, intensities and dither patterns.
  • Earlier generation displays (circa 2006 and prior) had phosphors that lost luminosity over time, resulting in gradual decline of absolute image brightness (newer models may be less susceptible to this, having advertised lifespans exceeding 100 000 hours, far longer than older CRTtechnology)[4][7]
  • Screen-door effects (black lines between rows of pixels) become noticeable on screen sizes larger than 127 cm (50 in); the effect is more visible at shorter viewing distances.[11]
  • Uses more electrical power, on average, than an LCD TV.[12]
  • Does not work as well at high altitudes above 2 km[13] 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 the altitude parameters.[13]
  • 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.[14]
  • Plasma displays are generally heavier than LCD, and may require more careful handling such as being kept upright.

Native plasma television resolutions[edit]

Further information: Native resolution

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 853×480 (EDTV), 1,366×768 or 1,920×1,080 (HDTV). As a result picture quality varies depending on the performance of the video scaling processor and the upscaling and downscaling algorithms used by each display manufacturer.[15][16]

Enhanced-definition plasma television[edit]

Main article: Enhanced-definition television

Early plasma televisions were enhanced-definition (ED) with a native resolution of 840×480 (discontinued) or 853×480, and down-scaled their incomingHigh-definition video signals to match their native display resolution.[17]

ED Resolutions[edit]

Following ED resolutions were common prior to the introduction of HD displays, but have long been phased out in favor of HD displays.

  • 840×480p
  • 853×480p

High-definition plasma television[edit]

Early high-definition (HD) plasma displays had a resolution of 1024x1024 and were alternate lighting of surfaces (ALiS) panels made byFujitsu/Hitachi.[18][19] These were interlaced displays, with non-square pixels.[20]

Modern HDTV plasma televisions usually have a resolution of 1,024×768 found on many 42 inch plasma screens, 1,280×768, 1,366×768 found on 50 in, 60 in, and 65 in plasma screens, or 1,920×1,080 found in plasma screen sizes from 42 inch to 103 inch. These displays are usually progressive displays, with square pixels, and will up-scale their incoming standard-definition signals to match their native display resolution.[21]

HD Resolutions[edit
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