OLED TV sets have become among the biggest and most awaited TV attractions in electronics shows. This is no surprise; OLED technology promises exceptionally thin display panels, lightweight TVs, least power consumption, and a superior picture to that of any other display technology available today.
It was only during CES 2012 when we saw the first 55-inch OLED HDTVs; and as we all know, 2012 did not bring the OLED TV to the consumer market – instead, we had to wait till 2013 for the ‘big’ event. By the way, do not expect OLED TV technology to become the mainstream technology anytime soon; OLED televisions are still among the most expensive TVs you can buy!
It may not be the time to jump on to the OLED bandwagon, at least not at the present price levels. Yet it is definitely the time to get to know more about what is available, the pros and cons of OLED displays, and what is behind this technology. It is here that this OLED technology guide comes in.
Finally, the much awaited OLED TV is a consumer reality!
Some Historical Background
LG Electronics 55EC9300 55-Inch
Many may think that OLED or organic light emitting diode, is the latest in display technology, yet it was in the late 80’s when scientists first started experimenting with OLED’s.
However, since then, what we have seen were just prototype TVs and the use of OLED screens in small personal entertainment devices and few digital cameras. Development was rather slow due to the rather very expensive OLED production process that relied on vacuum depositing.
The first prototype OLED TV appeared in May 2005; it was an ultra-slim 720p Samsung HDTV that was just an inch thick; definitely super thin at a time when most flat-panel TVs were at least 3.5-inches deep. This TV was expected to sell for tens of thousands of dollars, but eventually it never made it to the consumer market.
In 2007, there came Sony with its XEL-1 OLED TV, an 11-inch OLED TV that had a list price of around $2500; surely super expensive for a small 11-inch TV that was more of a prototype than a commercial model!
However, it was not before CES 2012 that we saw the first really big screen OLED TVs, when both LG and Samsung presented their first 55-inch OLED TV exhibits; these came with a 1080p screen resolution. Both TV makers promised their TVs will make it to the consumer market during 2012, but 2012 was not to be the year of the OLED TV!
Instead, it is 2013 the year for the OLED TV, with both LG and Samsung taking pre-orders for their much awaited OLED TVs; these are the Samsung KN55S9C and the LG 55EM9800. Both OLED TVs come with an average size 55-inch screen, and both TVs have a slightly curved screen surface. Despite what Samsung and LG are saying about the picture benefits of curved TV screens, the curved screen is mainly there to help these TV makers differentiate their OLED TVs from traditional plasma and LED LCD TVs than because of some added picture benefit; rather, the only real major picture benefit is derived out of the use of OLED picture technology.
Worth taking note that though both TVs make use of the same OLED picture technology, there are a few important differences between the two models:
As we will explain further on in this article, Samsung and LG make use of different OLED picture technologies – each of which has its pros and cons with respect to the other.
While the LG OLED TV is impossibly thin at just 4mm, Samsung’s version looks more in line with a typical inch-thin LED TV.
As expected, both are very expensive but the LG OLED TV is exorbitantly expensive – with a pre-order price tag of $14,999! That’s $6,000 more than the Samsung OLED TV! In fact, at $9,000, the Samsung KN55S9C is cheaper than what many analysts expected. We believe the lower price of the Samsung OLED TV would eventually push LG towards correcting the price tag of its OLED TV.
What is OLED Display Technology?
It is not the scope of this article to go into the details of how OLED display technology works; there is a lot of information in this respect on the Internet. Prior to continuing with this discussion, it is important to have a basic understanding of what is this ‘Organic Light Emitting Diode’ display technology. This is important as there are many misconceptions surrounding ‘organic’ LED; many often correlate the use of the word ‘organic’ in OLED technology with the use of the same word in the food and organic farming industry. There is no such relation at all!
In most simplistic terms, OLEDs are solid-state devices like standard LEDs except that OLEDs are made from multiple layers of ultra-thin films (typically less than 200 times the thickness of the human hair) of carbon-based molecules, hence the term organic. These create light when electricity is applied between the anode and cathode. The color of the light generated in the process depends on the organic materials used.
OLED displays are more efficient, theoretically, they are simpler to make, much thinner than standard LED-based displays, and support a great picture quality. Rather, OLEDs support the best picture today’s flat-panel display technologies can deliver, one characterized by highly saturated colors, true blacks, a bright image, fast pixel response, and a super wide viewing angle.
The video clip shown here by the Edison Tech Center explains in a most interesting and simplified manner, the main technical differences between LED and OLED technologies.
OLED: The Most Important Advancement in the TV Display Industry
There is no doubt that OLED display technology represents the most important advancement in the TV display industry since the first plasma and LCD flat-panel TVs appeared on the market over a decade ago. Why?
This is the only display technology that can create light – colored light – to form an image directly by passing current through appropriate materials. LCD needs a backlight behind color filters in conjunction with the blocking properties of a liquid crystal to create the image; plasma uses UV to ignite the red, green, and blue phosphors in the display panel sub-pixels to form the image. This has a few important implications in flat-panel display technology:
The fact that each sub-pixel generates its own light — combined with the super thin OLED pixel structure — yields a display panel capable of an almost 180-degrees viewing angle with practically zero degradation in image quality as one moves towards extreme viewing angles.
In addition, combining this ability of OLEDs to produce light with the super-fast response of OLEDs, leads to a display where each individual pixel can be completely and independently shut off in an instant to produce absolute black. The result is that OLED is the only flat-panel display technology capable of true ‘infinite’ contrast ratio. This is something that even the best plasma TVs from Panasonic cannot produce due to the afterglow of the phosphors at the instant the pixel is switched off.
Yet there is more in favor of OLED display technology. The OLED display structure supports super thin display panels that are much lighter, consumes some 50% less energy than even the most efficient LED-backlit LCD TVs despite the brighter OLED image, and can accommodate a better pixel fill, thus supporting higher resolution displays for the same screen size. This in particular makes OLED the ideal display technology for the latest 4K Ultra HD TVs
Add the more accurate color and the wider color gamut supported by OLEDs, and there you have the perfect display technology. Well… almost!
Nothing is perfect!
Unfortunately, we live in a world where nothing is perfect! OLED televisions are going to have an astronomically high price tag – one equivalent to three to five times that of a 65-inch flagship plasma TV from Panasonic! According to industry analysts, we should not expect any major drop in OLED TV pricing prior to 2015.
Definitely, this is too expensive for a 55-inch HDTV, especially when you compare this with what today’s best HDTVs using traditional flat-panel display technologies have to offer for much less.
At this price level, it will take years for the OLED TV to start making it to the average household, even though sales of OLED televisions are expected to reach 1.7 million units by end 2014.
Long-term reliability: In the past, the main problem with OLED display stability has been the reduced lifetime of the blue-light organic material. The reason being that the organic material used to produce blue light is less efficient, thus requiring a higher drive current for the blue to match the intensity of the red and green sub-pixels. This higher drive current however leads to a higher operating temperature and hence a faster aging rate.
The industry is saying that this issue has now been resolved as present organic materials used to produce blue light supports a rated lifetime of 33,000hrs; this is considered good enough for TV applications.
Yet… There is definitely no better test than time to determine long-term reliability of the latest OLED display technology. In the meantime, we have to trust the manufacturing industry!
2013 OLED TVs
As expected, OLED TVs were among the biggest attractions in CES 2013, even though what we have seen during CES 2013 were mainly prototypes rather than ready-for-production products.
During this year show, both Samsung and LG were among the most predominant TV makers in the OLED TV arena; in particular, their curved 55-inch OLED TV prototypes did attract a good level of attention. However, in our opinion, the most interesting OLED television options did not come from LG or Samsung but from Sony and Panasonic; no curved TVs but their 56-inch OLED TV exhibits made use of a new production methodology that is cheaper to implement. The downside… these TVs are not expected to make it to store shelve, at least not before mid-2014.
In this respect, the only TV makers to deliver a big screen OLED TV for the consumer market are Samsung and LG, with the models already referred to above, so… do not expect more OLED televisions to reach the market this year!
LG Electronics 55EA9800
The 55EM9800 OLED HDTV is basically the 2013 equivalent to LG’s 55EM9700 we have seen during CES2012, but with a slightly curved screen. Apart from being the most expensive, it is also the thinnest TV presently available; at just 4.5mm thick at the panel thinnest point, it is significantly thinner than the Samsung OLED TV proposal.
This ultra slim panel design has been made possible thanks to the use of carbon fiber-reinforced plastics into the rear of the television, thus providing the necessary support while keeping weight down to just 38 pounds, that is half the weight a typical 55-inch LED TV. Complimenting the slim design is an equally incredible 1mm-thick bezel.
The slim design calls for the use of an external media hub – same as Samsung breakout box concept that connects to the TV panel via a single cable to provide both AV connectivity to the outside world and power; this is necessary to house all relevant electronics and AV connections.
Yet there is more than just a most appealing and incredibly slim design. This OLED TV comes with what the industry is calling ‘infinite’ contrast ratio, one that is more than 100,000,000:1; so no more mega ratings as we were used to with LED TVs, instead, the terminology has now shifted to infinite contrast!
LG is making use of a new pixel architecture called W-OLED, or White-OLED that generates white light only for each sub-pixel element; colored filters are then used to generate the color information.
Instead, ‘direct-patterned’ RGB OLED uses the conventional red, green, and blue sub-pixel structure where each OLED sub-pixel emits its own colored light; this is very much the same in concept as the pixel structure in a plasma display.
Both the White-OLED and RGB OLED have their pros and cons as we will further explain in this article. Direct-patterned RGB OLED is what Samsung is using on its OLED TVs.
The main advantage of RGB OLED is that no color filters are used since each sub-pixel generates its own colored light. We do not have any information on how much light is blocked by the color filters used in W-OLED pixel, but in LCD displays, the use of color filters can block as much as 70% of the light from the backlight source. Hence, removing the color filters as in the case of RGB OLED, should yield a more efficient TV display.
The main problem with this conventional direct-patterned RGB OLED emitter approach is that the different organic materials for the red, green, and blue sub-pixels age at different rates over time. This differential aging with time leads to color shifts as one sub-pixel color within the RGB OLED fads more quickly than the others.
LG adopted a smart twist to the conventional RGB OLED pixel structure by sandwiching the red, green, and blue organic materials, effectively stacking the blue, green, and red OLED film deposits on top of each other for each sub-pixel element.
The resultant organic sandwich produces white light instead of colored light once activated, hence the name While OLED, or W-OLED.
This means that each sub-pixel in a W-OLED display produces only white light. Color is added by adding red, green, and blue color filters on top of the white light emitting sub-pixel organic sandwich. LG uses the term ‘Color Refiner’ instead of color filters, but these are in effect red, green, and blue color filters placed on top of the white-light emitting sub-pixels.
Unlike the differential aging of the direct-patterned red, green, and blue sub-pixel structure in an RGB OLED, the resultant white light OLED formulation exhibits a more stable performance with no color shifts over an expected lifetime in excess of 100,000hrs! This means that unlike RGB OLED, with W-OLED there is a complete elimination of color shift since each sub-pixel ages at exactly the same rate as the rest of the sub-pixels within the pixel structure.
LG did not stop there however; there is also a fourth sub-pixel element in LG’s White OLED pixel structure, a white sub-pixel. This fourth sub-element within the pixel structure does not include any color filters on top. The diagram here by LG depicts the RGBW sub-pixel structure as used by LG in its White OLED display technology. This extra white sub-pixel is said to help produce a brighter image while allowing for a wider color gamut and more accurate colors.
Compared to conventional direct patterned individual RGB sub-pixel emitters, White OLED pixel architecture offers additional advantages apart from the improved long-term color stability referred to above. In particular, White-OLED technology is easier to produce, highly scalable over large substrates, requires lower manufacturing times, and has a high production yield. This means that LG’s White OLED display technology should be less expensive to produce.
Like LG, Samsung had originally revealed its OLED TV during CES 2012. At that time, it lacked a model number and final specs. With CES 2013, things were a bit different and more complete.
The new Samsung OLED TV (originally labelled as KN55F9500 during CES2013) is the 55-inch KN55S9C. Like the LG version, this is a 1080p OLED HDTV. Samsung is referring to the OLED display technology used on its S9C as ‘real OLED‘ to emphasis the use of the direct-emission OLED architecture. Once released, it will be the first OLED TV that uses this OLED technology at this screen size. As expressed above, this makes use of red, green, and blue light emitting sub-pixels without the use of any color filters (unlike LG’s proposal).
Samsung says its Real OLED technology offers better picture quality and improved energy efficiency over the White OLED design employed by LG. It is still too early to know to what extent this is the case; yet we expect the Samsung version to be more efficient as the color filters on top of the white emissive layer in W-OLED displays will inevitably block some of the light. This possibly explains the use of a white sub-pixel in the LG solution to ensure a bright enough TV image. However, direct-emission RGB OLED technology is more difficult to produce and to upscale over larger displays because the smaller OLED sub-pixels require precise patterning.
This Samsung OLED TV is available for pre-order at $9,000 – significantly cheaper than the LG equivalent. Still this is much more expensive than even the most expensive 65-inch flagship plasma TVs from Panasonic. Yet… for those money no-problem videophiles, the OLED TV picture quality is definitely superior to that of even the best plasma TVs. It is true that at 55-inch, many videophiles may consider these TVs a bit too small by today’s standards, but a first ‘hands-on review’ of the Samsung OLED TV by Cnet shows that the OLED TV picture is definitely better than plasma – with visibly better blacks.
More OLED TVs… but not for 2013!
Sony and Panasonic 56-inch 4K OLED Televisions: A new way of making OLED displays
While both Samsung and LG seems ready to take the lead in OLED TV production, the most interesting OLED TV exhibits during CES2013 did not come from LG or Samsung but from Sony and Panasonic, with the latter two companies unveiling 56-inch 4K OLED TV prototypes that they say should be ready for production by mid-2014.
What makes the Sony and Panasonic exhibits particular interesting is that these combine the new OLED display technology with the latest 4K Ultra HD resolution, using a new OLED production process that is both cheaper and scalable.
The two companies are collaborating on OLED technology development, thus explaining various similarities between the two prototypes, like the use of a similar top-emission structure with a transparent cathode and a TFT substrate, and the use of a 56-inch size for their OLED displays. However, similarities stop there… when it comes to the actual OLED production process, these two TV makers went their own way.
Sony is using a hybrid printing/evaporation process done by a Taiwan based company where the red and green light-emitting sub-pixels are laid down using a modified inkjet printing method, while the blue sub-pixel light emitting material is deposited using evaporation process.
Instead, Panasonic is using in-house RGB all-print technology to make its OLED displays. The Panasonic OLED production process deposits soluble organic materials using ink-jet printing technology. The picture here shows the Panasonic OLED TV exhibit during CES 2013; it was advertised by Panasonic as the largest 4K OLED TV presently available in the industry.
Using an OLED production process based on an all-printing method means production costs should be more acceptable than with evaporation-based technology.
Unlike Sony, Panasonic is using a color filter layer over the red, green, and blue light-emitting sub-pixels; the scope is to fine tune the emission color and achieve high color purity. This appears to be a sort of hybrid between While-OLED and RGB OLED technology. According to Panasonic, these OLED display panels are capable of great image quality with superb color reproduction, high contrast, and exceptionally fast pixel response time; and as expected, they are also ultra-thin and extremely light.
Ink-Jet printing is a promising manufacturing technology in the production of OLED panels as it is quick, precise (i.e. highly repeatable), supports high pixel densities, and extremely efficient with very little material waste during production.
It is definitely encouraging to see major brands like Samsung, LG, Panasonic and Sony making such good progress in OLED technology. In particular, the outcome from Sony and Panasonic represents a major development in the production of OLED TVs since it is the technology that theoretically has the potential to deliver OLED displays at a more reachable price.
Yet as stated earlier on, do not expect much choice for 2013 other than the two OLED TVs from Samsung and LG.
Even more so, do not expect this technology to become a mainstream TV display technology in home entertainment any time soon. It will definitely take years for this to happen; the astronomically high prices for OLED TVs are not expected to start falling prior to 2015. Even then, OLED TVs will probably remain the most expensive display technology to buy despite that OLED technology has the potential to deliver even cheaper TVs than plasma and LED LCD TVs! Why?
TV makers have all the cards in their hands to keep asking the higher price. OLED is simply the TV display technology that supports the best TV picture, the thinnest TV panel, and the most efficient TV. Surely, having a TV with the best picture, the thinnest panel and the most eco-friendly is the ultimate demanding high-end consumers would be looking for.
The irony is…
The best flagship plasma HDTVs from Panasonic cost just a fraction of the cost of an OLED TV, yet these are still capable of a superb picture irrespective of display technology, one that will surely more than suffice for even the most demanding videophiles.
Rather, we dare say that the difference in picture quality between the best plasma TVs and OLED TVs is such that you would need a trained eye under controlled light environment to really appreciate the difference. It is practically impossible to perceive such differences under most living room environments!
You see, OLED TVs may come with ‘infinite contrast ratio’ while present day flat-panel TVs support mega contrast ratios, yet as further explained in our TV contrast ratio guide, there is a limit to what your eye can see.
Do not take us wrong; there is no doubt that OLEDs support a superior picture yet… is this worth the exceptionally high price TV makers are asking for their OLED TVs at this moment in time?