[b]Are there any differences between the two technologies?[/b]
When it comes to flat screen TVs the two technologies LCD and Plasma seem very alike with almost lifelike images and the ability to be hung on the wall. Although LCD tvs and Plasma tvs displays may look very similar in the shops, there are various differences between the two technologies.
How does an LCD (Liquid Crystal Display) television work ?
LCD is an abbreviation for Liquid Crystal Display. A LCD tv screen is made up of two clear panels between which is a matrix of colour liquid filled pixels. These pixels respond to a small voltage which makes them change state by twisting or untwisting which allows light to pass through them or to be blocked depending on the state of the pixel. This process of twisting takes very little power. The pixels are either red, green or blue and they are structured in a matrix of millions of pixels to make a picture. The coloured pixels of the panel are illuminated from Behind with a back light to show their colour, and areas of light and dark, depending on how the pixels are twisted. Lcd screens are available in small sizes for watches up to 108 inches for large televisions. Manufacturers such as LG, Samsung, Hitachi, Panasonic, JVC, Pioneer, Sharp, Toshiba, Philips and Sony have a range of lcd televisions available.
How plasma tvs works
A Plasma tv screen comprises of millions of minute 'light bulbs' which are tiny glass cells filled with inert gases such as xenon and neon. These cells are illuminated by a current being applied to electrodes in the gas filled cell and its atoms become 'excited' to a plasma and emit photons of ultraviolet light. These photons in turn strike a phosphor coating which emits visible light. The colour of the visible light emitted by each cell depends on the three different coloured phosphors - green, blue and red, and can together make billions of colours when combined. As with the LCD tv screen, the millions of cells intermix to form the image on the screen. Currently the only manufacturers of Plasma tvs in the UK are Samsung, Philips, LG, Panasonic, and Pioneer. Plasma tvs are available in sizes from 32 inches to 150 inches.
A comparison of the Picture quality and Performance
Brightness
The picture on LCD tv screens can be brighter than Plasma tvs. Depending on where the television is located and what is being viewed will determine how this difference in screen brightness is perceived. However both Plasma tv and LCD tv screens are capable of producing brightness levels that in normal viewing conditions are in excess of what is needed.
Contrast Ratio and Black Levels
This is a measure of the difference of the luminosity of the brightest white on the screen and the darkest black. So a contrast ratio of 3000:1 means that the brightest white is 3000x brighter than the darkest black. Details can be more easily differentiated the higher the contrast ratio is as long as the the black levels aren't 'grey'. Previous models of LCD tvs had lower contrast ratio than plasma tvs because the pixels weren't able to block the back light for dark areas and the light would leak through making the image lighter. Improvements in technology have reduced this leakage so that the contrast ratio is much closer to those of plama tvs. But ultimately plasmas are able to produce blacker blacks because the pixel cells are able to be switched off instead of blocking the light as lcd tvs do. The blacker the black on a tv the better the picture quality it is able to produce. The colour saturation or colour palette is affected if the blacks aren't black enough . When the black level on a plasma is compared with the black level on an comparable priced LCD tv, the plasma tv black often makes the LCD tv black look grey.
Levels of Colour Saturation
This is a gauge of the accuracyof the colours on the screen based on the presence of grey shades - the higher grey shades results in lower colour saturation. Plasma TVs have high colour saturation due to the way they emit light. The ability of Plasma tv pixels to be turned off when they are not in use prevents the emission of stray light that diffuses colour. This is why tints and hues on Plasma TVs are noticeably more vivid and vibrant
Colour Gamut
The colour gamut is a measure of the number of colours that a screen can display. For the most expensive models of LCD tvs and Plasmas tvs the manufacturers are now claiming to have colour gamuts very close to the full spectrum. Again on a like for like basis the Plasma tvs still out perform the LCD tvs on all but the most expensive models. This is because on cheaper LCD tv models the colour gamut isn't as good as the top LCD tv models from the same manufacturer. Whereas for Plasma tvs the difference isn't as great.
TV Screen Resolution
This can be defined as the amount of information shown on a screen. The more information that is on a screen the higher the quality of the image. The higher resolution usually means that the screen can display a higher quality image with more detail and sharpness. The resolution is measure in pixels. LCD HDTVs and Plasma HDTVs (High Definition Televisions) have a resolution of 1920 pixels x 1080 pixels or 1080P. Where '1080' is the vertical resolution and 'P' is progressive scan meaning that the image isn't interlaced. Usually LCD HDTVs are cheaper than the same sized Plasma's. HD plasma are available in sizes of 42 inches upwards whereas LCD HDTVs are available from 32 inches upwards. Therefore at sizes 32 inches to 37 inches LCD tvs have the advantage of offering 1080P HD compared to the 720P (1280 pixels x720 pixels) HD Ready Plasma tvs. At sizes less than 32 inches there aren't any plasma tv models.
Refresh Rate and Response Time
These two attributes in combination influence how fast a moving picture a screen can reproduces without the image blurring. Response time is a measure of how rapidly a screen can vary when an input is received. Historically LCD tv panels had slow response times which was the limiting factor causing motion blur because each pixel has to go from an on state, to an off state, and back to on in order to refresh an image. Improvements in pixel response times on LCD tv screens means that the actual response time isn't the main cause of motion blur, its generally caused by the refresh rate, or the frame rate.
Lower model of LCD televisions and Plasma televisions operate at a frame rate of 50hz or 50 frames per second. In fact until recently, before 100hz models were launched, all models operated at 50 Hz. Now on more expensive models of LCD tv and Plasma tv motion blur is reduced with the addition of 100hz which create an extra frame that is placed between the normal frames. Because a normal signal is 50 Hz an additional middle frames is created by signal processing software that interpolates what the extra middle frame should look like. This results in picture motion that is more fluid and looses little if any definition. However the best Plasma tvs still show fast moving images better than the best LCD tvs but the difference is narrowing because the LCD tvs response time has reduced and 100hz and 200hz models have been established.
Viewing Angle
This is the maximum side angle that a viewer can see the image on the screen clearly. Plasma tvs usually have a viewing angle of between 160 degrees to 180 degrees whereas LCD tvs have a viewing angle of around 100 degrees after which the picture dulls.
The screen surface of lcd tvs and plasma tvs
A plasma tvs screen is a shinny reflective surface which can suffer from glare depending on the room conditions, whereas LCD tv screens have matt finish that reduces glare.
Burn-in
This can result if a static image is shown on the screen for an extended time, and even after the image is changed or removed, the 'ghost image' of the previously displayed static image is still visible on the screen for the remainder of the screens life. burn-in doesn't take place on LCD tvs. Though the chance of burn-in on plasma tv is usually exaggerated and improbable.
Image retention
A lot of people confuse burn-in with image retention which is very similar. With image retention the 'ghost image' disappears quickly either when a new, bright image is displayed or after a few seconds. image retention is infrequently noticed but normal on plasma tvs because of the technology utilized, but it can be minimised by having a 'break-in' period when the plasma tv is first purchased. The break-in period usually lasts 100 hours, during this time you should not view any programs that do not fill in the whole screen, and you should notview any programsthat have static images such as bright station logos or news scrolls at the base of screens, and you should decrease the contrast and brightness to a mid level. Nowadays there are also features built in to the plasma tvs to reduce the possibility of either burn-in or image retention.
Power consumption
LCD tvs have a backlight that is continuously on and uses virtually constant power. LCD tvs usually have an adjustable back light which uses extra power when it is on a high setting and not as much of on a low setting. The power required to modulate the pixels is infinitesimal.
However Plasma tvs charge a gas to a plasma to produce light. The more light that is requisite the more often this is done. So it's usual for plasma tvs to want more energy on an image with high levels of brightness, and less energy on low brightness scenes. As a result the power consumption varies.
The energy requirements that are quoted for Plasma tvs are for full brightness settings. The effect of this is that lcd tvs seem to use less power than plasma tvs. But the power consumption of a plasma tv varies depending on the amount of dark and bright areas on the displayed image. Studies have found that when the viewed programs are mainly dark or on movies the amount of power consumed for plasma tvs will be lower than an lcd tv. However when the viewed programs are sports and cartoons the power consumption for plasma tvs is greater than on lcd tvs. When varied programs are viewed the power consumption is similar for LCD tvs and Plasma tvs. Future plasma tvs are going to consume less than half the amount power consumed at present.
Life expectancy
It is common myth that is quoted that plasma tv screens don't last very long. However manufacturers such as Panasonic are quoting a life expectancy of 100000 hours which is 11.5 years of continuous use. Therefore any concerns are unsubstantiated
[b]Conclusion - which should you buy?[/b]
Plasma televisions and LCD televisions both have advantages and disadvantages. LCD tvs have higher brightness, no concerns about screen burn, and they are thinner and lighter. But Plasma tvs have a better real world picture with a higher contrast, blacker blacks, and more natural colours than LCD tvs. Obviously not all Plasma tvs are better than all LCD tvs. A top specification LCD tv will out perform a cheap plasma tv. If you weigh up the advantages and disadvantages a good plasma tv is the best option but you do get what you pay for.
When it comes to flat screen TVs the two technologies LCD and Plasma seem very alike with almost lifelike images and the ability to be hung on the wall. Although LCD tvs and Plasma tvs displays may look very similar in the shops, there are various differences between the two technologies.
How does an LCD (Liquid Crystal Display) television work ?
LCD is an abbreviation for Liquid Crystal Display. A LCD tv screen is made up of two clear panels between which is a matrix of colour liquid filled pixels. These pixels respond to a small voltage which makes them change state by twisting or untwisting which allows light to pass through them or to be blocked depending on the state of the pixel. This process of twisting takes very little power. The pixels are either red, green or blue and they are structured in a matrix of millions of pixels to make a picture. The coloured pixels of the panel are illuminated from Behind with a back light to show their colour, and areas of light and dark, depending on how the pixels are twisted. Lcd screens are available in small sizes for watches up to 108 inches for large televisions. Manufacturers such as LG, Samsung, Hitachi, Panasonic, JVC, Pioneer, Sharp, Toshiba, Philips and Sony have a range of lcd televisions available.
How plasma tvs works
A Plasma tv screen comprises of millions of minute 'light bulbs' which are tiny glass cells filled with inert gases such as xenon and neon. These cells are illuminated by a current being applied to electrodes in the gas filled cell and its atoms become 'excited' to a plasma and emit photons of ultraviolet light. These photons in turn strike a phosphor coating which emits visible light. The colour of the visible light emitted by each cell depends on the three different coloured phosphors - green, blue and red, and can together make billions of colours when combined. As with the LCD tv screen, the millions of cells intermix to form the image on the screen. Currently the only manufacturers of Plasma tvs in the UK are Samsung, Philips, LG, Panasonic, and Pioneer. Plasma tvs are available in sizes from 32 inches to 150 inches.
A comparison of the Picture quality and Performance
Brightness
The picture on LCD tv screens can be brighter than Plasma tvs. Depending on where the television is located and what is being viewed will determine how this difference in screen brightness is perceived. However both Plasma tv and LCD tv screens are capable of producing brightness levels that in normal viewing conditions are in excess of what is needed.
Contrast Ratio and Black Levels
This is a measure of the difference of the luminosity of the brightest white on the screen and the darkest black. So a contrast ratio of 3000:1 means that the brightest white is 3000x brighter than the darkest black. Details can be more easily differentiated the higher the contrast ratio is as long as the the black levels aren't 'grey'. Previous models of LCD tvs had lower contrast ratio than plasma tvs because the pixels weren't able to block the back light for dark areas and the light would leak through making the image lighter. Improvements in technology have reduced this leakage so that the contrast ratio is much closer to those of plama tvs. But ultimately plasmas are able to produce blacker blacks because the pixel cells are able to be switched off instead of blocking the light as lcd tvs do. The blacker the black on a tv the better the picture quality it is able to produce. The colour saturation or colour palette is affected if the blacks aren't black enough . When the black level on a plasma is compared with the black level on an comparable priced LCD tv, the plasma tv black often makes the LCD tv black look grey.
Levels of Colour Saturation
This is a gauge of the accuracyof the colours on the screen based on the presence of grey shades - the higher grey shades results in lower colour saturation. Plasma TVs have high colour saturation due to the way they emit light. The ability of Plasma tv pixels to be turned off when they are not in use prevents the emission of stray light that diffuses colour. This is why tints and hues on Plasma TVs are noticeably more vivid and vibrant
Colour Gamut
The colour gamut is a measure of the number of colours that a screen can display. For the most expensive models of LCD tvs and Plasmas tvs the manufacturers are now claiming to have colour gamuts very close to the full spectrum. Again on a like for like basis the Plasma tvs still out perform the LCD tvs on all but the most expensive models. This is because on cheaper LCD tv models the colour gamut isn't as good as the top LCD tv models from the same manufacturer. Whereas for Plasma tvs the difference isn't as great.
TV Screen Resolution
This can be defined as the amount of information shown on a screen. The more information that is on a screen the higher the quality of the image. The higher resolution usually means that the screen can display a higher quality image with more detail and sharpness. The resolution is measure in pixels. LCD HDTVs and Plasma HDTVs (High Definition Televisions) have a resolution of 1920 pixels x 1080 pixels or 1080P. Where '1080' is the vertical resolution and 'P' is progressive scan meaning that the image isn't interlaced. Usually LCD HDTVs are cheaper than the same sized Plasma's. HD plasma are available in sizes of 42 inches upwards whereas LCD HDTVs are available from 32 inches upwards. Therefore at sizes 32 inches to 37 inches LCD tvs have the advantage of offering 1080P HD compared to the 720P (1280 pixels x720 pixels) HD Ready Plasma tvs. At sizes less than 32 inches there aren't any plasma tv models.
Refresh Rate and Response Time
These two attributes in combination influence how fast a moving picture a screen can reproduces without the image blurring. Response time is a measure of how rapidly a screen can vary when an input is received. Historically LCD tv panels had slow response times which was the limiting factor causing motion blur because each pixel has to go from an on state, to an off state, and back to on in order to refresh an image. Improvements in pixel response times on LCD tv screens means that the actual response time isn't the main cause of motion blur, its generally caused by the refresh rate, or the frame rate.
Lower model of LCD televisions and Plasma televisions operate at a frame rate of 50hz or 50 frames per second. In fact until recently, before 100hz models were launched, all models operated at 50 Hz. Now on more expensive models of LCD tv and Plasma tv motion blur is reduced with the addition of 100hz which create an extra frame that is placed between the normal frames. Because a normal signal is 50 Hz an additional middle frames is created by signal processing software that interpolates what the extra middle frame should look like. This results in picture motion that is more fluid and looses little if any definition. However the best Plasma tvs still show fast moving images better than the best LCD tvs but the difference is narrowing because the LCD tvs response time has reduced and 100hz and 200hz models have been established.
Viewing Angle
This is the maximum side angle that a viewer can see the image on the screen clearly. Plasma tvs usually have a viewing angle of between 160 degrees to 180 degrees whereas LCD tvs have a viewing angle of around 100 degrees after which the picture dulls.
The screen surface of lcd tvs and plasma tvs
A plasma tvs screen is a shinny reflective surface which can suffer from glare depending on the room conditions, whereas LCD tv screens have matt finish that reduces glare.
Burn-in
This can result if a static image is shown on the screen for an extended time, and even after the image is changed or removed, the 'ghost image' of the previously displayed static image is still visible on the screen for the remainder of the screens life. burn-in doesn't take place on LCD tvs. Though the chance of burn-in on plasma tv is usually exaggerated and improbable.
Image retention
A lot of people confuse burn-in with image retention which is very similar. With image retention the 'ghost image' disappears quickly either when a new, bright image is displayed or after a few seconds. image retention is infrequently noticed but normal on plasma tvs because of the technology utilized, but it can be minimised by having a 'break-in' period when the plasma tv is first purchased. The break-in period usually lasts 100 hours, during this time you should not view any programs that do not fill in the whole screen, and you should notview any programsthat have static images such as bright station logos or news scrolls at the base of screens, and you should decrease the contrast and brightness to a mid level. Nowadays there are also features built in to the plasma tvs to reduce the possibility of either burn-in or image retention.
Power consumption
LCD tvs have a backlight that is continuously on and uses virtually constant power. LCD tvs usually have an adjustable back light which uses extra power when it is on a high setting and not as much of on a low setting. The power required to modulate the pixels is infinitesimal.
However Plasma tvs charge a gas to a plasma to produce light. The more light that is requisite the more often this is done. So it's usual for plasma tvs to want more energy on an image with high levels of brightness, and less energy on low brightness scenes. As a result the power consumption varies.
The energy requirements that are quoted for Plasma tvs are for full brightness settings. The effect of this is that lcd tvs seem to use less power than plasma tvs. But the power consumption of a plasma tv varies depending on the amount of dark and bright areas on the displayed image. Studies have found that when the viewed programs are mainly dark or on movies the amount of power consumed for plasma tvs will be lower than an lcd tv. However when the viewed programs are sports and cartoons the power consumption for plasma tvs is greater than on lcd tvs. When varied programs are viewed the power consumption is similar for LCD tvs and Plasma tvs. Future plasma tvs are going to consume less than half the amount power consumed at present.
Life expectancy
It is common myth that is quoted that plasma tv screens don't last very long. However manufacturers such as Panasonic are quoting a life expectancy of 100000 hours which is 11.5 years of continuous use. Therefore any concerns are unsubstantiated
[b]Conclusion - which should you buy?[/b]
Plasma televisions and LCD televisions both have advantages and disadvantages. LCD tvs have higher brightness, no concerns about screen burn, and they are thinner and lighter. But Plasma tvs have a better real world picture with a higher contrast, blacker blacks, and more natural colours than LCD tvs. Obviously not all Plasma tvs are better than all LCD tvs. A top specification LCD tv will out perform a cheap plasma tv. If you weigh up the advantages and disadvantages a good plasma tv is the best option but you do get what you pay for.
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BeTo gete you buy any LCD tv or Plasma tv online, ensure you check Plasma tv or LCD tv Discounts. To get more inTo getmation go to LCD tv's and Plasma tv's at low prices
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