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| The Panasonic 42" VT30, recently awarded What HiFi's TV of the Year prize . |
The Plasma screens, whilst hugely expensive, were designed as TV's/Video displays from the outset & did produce good pictures. They were also viewable from anywhere in the room which suited peoples normal viewing habits. Slightly later, LCD's arrived on the shelves and were no where near in comparison. They could not be viewed from the sides, below or above and could not keep up with even the slowest football game without smearing the image. This said people did slowly start to buy the LCD's, possibly convinced by the slim design or their desirability, but this did allow the manufacturers to develop the product and improve on the obvious flaws in the design. Over the years LCD's have improved massively and removed most of the flaws from their original design, and now for most peoples needs, are an excellent option to replace the old CRT (tube) TV.
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| An early Panasonic 32" LCD from Panasonic the 32LXD1 |
Since LCD's have become the mass market screen of choice Plasma has almost become the forgotten technology to the general public. This is probably due to the fact that Plasma TV's are only available in larger screen sizes (42" & above) and as such are greatly outsold by LCD. These are able to be used in anything from your mobile phone to a 60"+ screen. The improvement in Plasma TV's during the last 10 years may not have been as large or as obvious as that of LCD's, but they did have a big head start and in my view are still ahead in terms of pure picture performance.
The differences between Plasma & LCD/LED screens for me mainly fall into three areas. This obviously does not cover the many differences in the design and construction, but more the final results on the screen.
- Black Levels
- Brightness/Vividness
- Motion Smearing/Pixel response time
Area 1:
Black levels on TV's seems like an odd thing to consider when you're going out to buy one, but they do play a critical role in picture quality. Having a darker level of black on the screen means that colours can also be richer and more accurate. It also means that those dark and moody horror films are all the more engrossing as the monsters appear from the inky black backgrounds. Plasma TV's have always excelled in this area and despite big strides by their counterpart will more than likely always have the edge. If you looking for a set with a more natural picture and are going to be watching TV in a normally lit room a Plasma is going to be a good solution.
Area 2:
Picture brightness is an area where LCD's really can excel, even more so with the latest generation LED versions. LCD's are illuminated in a few different ways, either from behind with a number of CCFL's or a matrix of LED's, although this is still uncommon and relatively expensive. LED's generally are placed at the edge with their light diffused across the back of the screen. This is the most common type of LED TV and has the advantage of also being very thin. Because they are illuminated they can be driven harder to produce a brighter picture. This obviously has a big advantage when placing the TV in a either a very brightly lit room or one that has lots of windows and natural light. LCD's also tend to suffer from less reflections on screen. This is mainly down to the fact that Plasma TV's have a glass panel at the front of the display and LCD's don't. Because of this additional brightness the colours tend to be very vivid (although potentially very unnatural in my opinion) and will suit some peoples tastes more than a Plasma TV. They also tend to be more suited for use as large screen PC monitors or in some ways for use with games consoles.
Area 3:
Motion Smearing and Pixel Response time has historically been very different between the two screen types. LCD's firstly became popular in the computer market where the desire to have laptops and also space saving desktop displays became apparent. For these roles the poor pixel response time and motion smearing were not of particular concern. At the time PC's did not really require the super quick response times that people expected from their TV screens, except perhaps for the hardcore gamers who would have stuck with their larger but generally better suited CRT monitors. This however did not stop the development within the industry to improve these issues with LCD screens. As the response times came down the idea of using them as TV screens became more attractive. LCD's now offer images that, in general perform extremely well under most circumstances and have a level of smearing that most people can happily accept when watching TV.
They do, however, have a long way to go to catch up with Plasma TV's. A modern LCD has a response just under 2 milliseconds, compared with the old CRT's of under 1ms and Plasma TV's at .001ms. The quicker response time not only makes Plasma TV's better at handling quick motion but also more suited to high quality 3D images. Plasma's can also be better for gaming where details during fast moving scenes need to be sharp and clear.
Additional but less critical differences between the two technologies include Power Consumption, Screen Burn and Viewing Angles.
Power Consumption is a thorny subject at the moment and will probably only get worse over time as we all become more environmentally concious and concerned about our spending. LCD's, and in particular those using LED lighting, are the most energy efficient amongst these three technologies. Plasma's do use more power but not as much as you may think when reading the labels on the back of the sets. Some current Panasonic sets highlight this for me. The 42" LED's rated power is 102watts but during average use will use about 70watts. This compares with the 42" Plasma (which is higher up in the range and also 3D) that has a rated power of 325watts but drops down to 130watts during average use. If you prefer the picture on a Plasma TV, the minimal extra running cost should be outweighed by your enjoyment of set.
Screen Burn can be an issue on both types of screen, but has generally been more common on Plasma displays. On most new sets, when used for everyday TV viewing, screen burn is almost a thing of the past. There is still the chance of screen burn if the sets are used in a manner contrary to their design. These sets are designed to display moving images and although they will display photos or static graphics, it is not their main purpose. If you do leave a static image on screen for long periods you can permanently damage the picture. A static image could also include the speedo' or health bar from your favourite game or the DOG that certain TV stations are determined to plaster over your favourite show. An example of a bad DOG below shows the Disney channel logo in the bottom left of the screen. This logo is very bright and is a solid colour. This will quite quickly start to burn into a Plasma screen if left unchecked. DOG's such as the BBC three logo below will not burn in because they are low intensity and also semi translucent.
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| This picture shows 6 TVs all displaying the same black image. The 3 Plasma TVs are clearly distinguishable as the pictures are far nearer to pure black than the 3 LED/LCD TVs |
Area 2:
Picture brightness is an area where LCD's really can excel, even more so with the latest generation LED versions. LCD's are illuminated in a few different ways, either from behind with a number of CCFL's or a matrix of LED's, although this is still uncommon and relatively expensive. LED's generally are placed at the edge with their light diffused across the back of the screen. This is the most common type of LED TV and has the advantage of also being very thin. Because they are illuminated they can be driven harder to produce a brighter picture. This obviously has a big advantage when placing the TV in a either a very brightly lit room or one that has lots of windows and natural light. LCD's also tend to suffer from less reflections on screen. This is mainly down to the fact that Plasma TV's have a glass panel at the front of the display and LCD's don't. Because of this additional brightness the colours tend to be very vivid (although potentially very unnatural in my opinion) and will suit some peoples tastes more than a Plasma TV. They also tend to be more suited for use as large screen PC monitors or in some ways for use with games consoles.
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| A naked CCFL back lighting array |
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| This picture shows 6 TVs all displaying the same white image. The 3 LED/LCD TVs are clearly distinguishable as the pictures are far brighter than the 3 Plasma TVs |
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| This picture shows 6 TVs all displaying the same white rectangle on black background image. In this shot you can see that the brightness on each of the LED/LCDs has fallen and is nearer to the levels found on the Plasma screens. The black areas are still however nowhere near those on the Plasma TVs |
Area 3:
Motion Smearing and Pixel Response time has historically been very different between the two screen types. LCD's firstly became popular in the computer market where the desire to have laptops and also space saving desktop displays became apparent. For these roles the poor pixel response time and motion smearing were not of particular concern. At the time PC's did not really require the super quick response times that people expected from their TV screens, except perhaps for the hardcore gamers who would have stuck with their larger but generally better suited CRT monitors. This however did not stop the development within the industry to improve these issues with LCD screens. As the response times came down the idea of using them as TV screens became more attractive. LCD's now offer images that, in general perform extremely well under most circumstances and have a level of smearing that most people can happily accept when watching TV.
They do, however, have a long way to go to catch up with Plasma TV's. A modern LCD has a response just under 2 milliseconds, compared with the old CRT's of under 1ms and Plasma TV's at .001ms. The quicker response time not only makes Plasma TV's better at handling quick motion but also more suited to high quality 3D images. Plasma's can also be better for gaming where details during fast moving scenes need to be sharp and clear.
Additional but less critical differences between the two technologies include Power Consumption, Screen Burn and Viewing Angles.
Power Consumption is a thorny subject at the moment and will probably only get worse over time as we all become more environmentally concious and concerned about our spending. LCD's, and in particular those using LED lighting, are the most energy efficient amongst these three technologies. Plasma's do use more power but not as much as you may think when reading the labels on the back of the sets. Some current Panasonic sets highlight this for me. The 42" LED's rated power is 102watts but during average use will use about 70watts. This compares with the 42" Plasma (which is higher up in the range and also 3D) that has a rated power of 325watts but drops down to 130watts during average use. If you prefer the picture on a Plasma TV, the minimal extra running cost should be outweighed by your enjoyment of set.
Screen Burn can be an issue on both types of screen, but has generally been more common on Plasma displays. On most new sets, when used for everyday TV viewing, screen burn is almost a thing of the past. There is still the chance of screen burn if the sets are used in a manner contrary to their design. These sets are designed to display moving images and although they will display photos or static graphics, it is not their main purpose. If you do leave a static image on screen for long periods you can permanently damage the picture. A static image could also include the speedo' or health bar from your favourite game or the DOG that certain TV stations are determined to plaster over your favourite show. An example of a bad DOG below shows the Disney channel logo in the bottom left of the screen. This logo is very bright and is a solid colour. This will quite quickly start to burn into a Plasma screen if left unchecked. DOG's such as the BBC three logo below will not burn in because they are low intensity and also semi translucent.
Lastly Viewing Angles. Generally the issue that LCD's had with very poor angles has, on the vast majority of decent sets, ceased to be a problem. The picture will still lose brightness as you go off centre but even at 70-80 degrees they are now perfectly viewable. Smaller LCD's and lower priced models will still suffer from this issue, in some cases severely.
At this point I would also like to point out that there are some rumours that have persisted over the years about Plasma's. These include "don't Plasma's have to be re-gassed?", "I've been told that I have to occasionally turn Plasma's upside down to re-distribute the gas" & "if a Plasma screen breaks will I need to mop up the plasma as it leaks out". These and other rumours have been muttered to us many times over the years and we really don't know the exact source of them. needless to say however they are all completely false and baseless. A Plasma or LCD TV needs no special attention at all other than the right cleaning materials.
The information above highlights why we find the original question difficult to answer. Our general conclusion is that there is now such a small difference in the overall performance of the sets that it doesn't really matter which one you choose....... Unless you happen to have a particular requirement that sits into one of the advantages listed above!
If you have no particular requirement our advice can be quite simple.
Simply choose the set on which you prefer the picture. At home you'll have nothing to compare to, and will 99% of the time, be delighted with the set.
If anyone tells you 100% categorically that one is better than the other they are probably doing so for another reason entirely!
G Kavangh,
Burden Electronics
