The first commercial available OLED TV was launched by Sony in 2007 and was received with mixed reviews. While its success is ingrained in our cultural memory now, when it was launched it was a  technologically inferior product. Before everything there was 3 generations: 1 Emission-type,  2. Phosphorescence 3. Thermally activated delayed fluorescence oled type. The first oled was designed  to offer the best possible TV picture quality. While oled was superior in most specs, it was still limited  in some ways. 

Screen brightness power and burn in were often mentioned. Reviewers of the time viewed these  features as a negative, but these compromises in design weren’t enough to stop oled developed and picture differences in contrast secured oled to succeed. This was a tv for the niche premium users. Even with these limitations, engineers  and programmers came up with ingenious methods to improve screen durability that have not only stood the test of time, but launched some of the most valuable OLED TVs in the history of the entertainment industry. In next decades LG, Sony and Samsung  have become the best OLED TVs manufacturers. 

The OLED’s complex design borrows much of its success from its older brother the Plasma TV screens. A straightforward and familiar screen design in terms of  infinity contrast. LG knew that picture quality and performance were the most important factors for a TV to be exclusive. The OLED TV have a better colors and contrast of its LCD or LED competitors. The biggest difference could be in the contrast ratio which is infinite at times when the best LCD tv could go further than 5000:1 , The first OLED devices on the market started from 1997 from pioneer, but oled technology was actually invented decades before in the late 80s by Chemists Ching Wan Tang and Steven Van Slyke at Eastman Kodak. 

Pioneer, Sony, Samsung and LG created first generation OLED TVs on the market in from 2007 to 2012 and the LG later focused on better user experience and lifespan of OLED TVs from the get-go, an ethos that has defined it to the best OLED tv company to this very day. But how did oled manage to make the tvs so much better? To begin, one of the primary technological limitations of LCD TVs were poor contrast. While many may recognize the difference between old cathode tvs the difference was mostly noticeable at night in dark scenes. These things were everywhere in the 90s. They were very affordable, so almost everyone could buy one. Large bulky box with small screen. But their price as much as possible was going to give these TVs an edge over any competitors. While LED tv could compete in terms of refresh and contrast in the colors it was quite close to the best.

This of course created better opportunities for new technology, LCD made the TVs more compact, and saved space for the consumer. Especially as the LCD TVs were much thinner and vastly minimised screen flickering. The OLED, with its extra organic light allowed deeper black levels vs LCD TVs at times, but it was still very expensive and available only in small screen sizes till the end of 2010s. 

I tried to explain to my father, who remembers getting the first color TV in his neighborhood, why we needed a smaller TV chassis instead of the bulky cathode ray tube (CRT) TVs. An LCD TV is a good investment if there isn’t enough space for a CRT TV.

One of the keys to OLED’s success was  recognizing this limitation of led lcde technology and working around it. While the first oled featured a 1 billion  coloured screen. The LG next generation featured a 1,2 billion color that was capable of  displaying much better response time that was impossible to see on any lcd tv because oled had a backlight that could control the brightness of every pixel. While the lcd may have gotten better  reviews with its screen retention lifespan, the oled got the customers with  a beauty and style against durability. The LG oled’s engineers were determined to use the best materials in the oled screens, and despite this screen being at start very expensive it gradually become more affordable and became  a success story today.

A typical OLED is composed of a layer of organic materials situated between two electrodes. The organic molecules are electrically conductive as a result of delocalization of pi electrons caused by conjugation over part or all of the molecule. Early prototypes of the oled used a two-layer structure with separate hole transporting and electron transporting layers such that recombination and light emission occurred in the middle of the organic layer. However, there was a problem. Originally, the most basic polymer OLEDs consisted of a single organic layer and limited power. However multilayer OLEDs can be fabricated with two or more layers in order to improve device efficiency.

 In other words, the bottom-emission organic light-emitting diode (BE-OLED) is the architecture that was used in the early-stage AMOLED displays. It had a transparent anode fabricated on a glass substrate, and a shiny reflective cathode. 

Using deuterium instead of hydrogen, in other words deuterated compounds, in red, green, blue and white OLED light emitting material layers and other layers nearby in OLED displays can improve their brightness by up to 30%. This is achieved by improving the current handling capacity, and lifespan of these materials. However, a breakthrough occurred in  the late 2000s. In “white + color filter method“, also known as WOLED, red, green, and blue emissions are obtained from the same white-light LEDs using different color filters. With this method, the OLED materials produce white light, which is then filtered to obtain the desired RGB colors.  This method eliminated the need to deposit three different organic emissive materials, so only one kind of OLED material is used to produce white light.

OLEDs also have a much faster response time than an LCD. Using response time compensation technologies, the fastest modern LCDs can reach response times as low as 1 ms for their fastest color transition, and are capable of refresh frequencies as high as 240 Hz. According to LG, OLED response times are up to 1,000 times faster than LCD, putting conservative estimates at under 10 μs (0.01 ms), which could theoretically accommodate refresh frequencies approaching 100 kHz (100,000 Hz).

We can’t perceive the pulsing with our eyes, but cameras can pick it up. The quest to make the oled as cheap as  possible of course created limitations elsewhere. OLEDs can be printed onto any suitable substrate by an inkjet printer or even by screen printing, theoretically making them cheaper to produce than LCD or plasma displays. However, fabrication of the OLED substrate as of 2018 is costlier than that for TFT LCDs. Roll-to-roll vapor-deposition methods for organic devices do allow mass production of thousands of devices per minute for minimal cost; however, this technique also induces problems: devices with multiple layers can be challenging to make because of registration — lining up the different printed layers to the required degree of accuracy.

The biggest technical problem for OLEDs is the limited lifetime of the organic materials. One 2008 technical report on an OLED TV panel found that after 1,000 hours, the blue luminance degraded by 12%, the red by 7% and the green by 8%. In particular, blue OLEDs at that time had a lifetime of around 14,000 hours to half original brightness (five years at eight hours per day) when used for flat-panel displays.  In 2016, LG Electronics reported an expected lifetime of 100,000 hours, up from 36,000 hours in 2013. A US Department of Energy paper shows that the expected lifespans of OLED lighting products goes down with increasing brightness, with an expected lifespan of 40,000 hours at 25% brightness, or 10,000 hours at 100% brightness.

The most commonly used patterning method for organic light-emitting displays is shadow masking during film deposition, also called the “RGB pixelation” method. Metal sheets with multiple apertures made of low thermal expansion material, such as nickel alloy, are placed between the heated evaporation source and substrate, so that the organic or inorganic material from the evaporation source is masked off, or blocked by the sheet from reaching the substrate in most locations, so the materials are deposited only on the desired locations on the substrate, and the rest is deposited and remains on the sheet. Almost all small OLED displays for smartphones have been manufactured using this method.

Unintentionally, this sparked a more efficient transfer printing worldwide.  Transfer-printing is an emerging technology to assemble large numbers of parallel OLED and AMOLED devices efficiently. It takes advantage of standard metal deposition, photolithography, and etching to create alignment marks commonly on glass or other device substrates. Thin polymer adhesive layers are applied to enhance resistance to particles and surface defects.

The bottom-emission organic light-emitting diode (BE-OLED) is the architecture that was used in the early-stage AMOLED displays. It had a transparent anode fabricated on a glass substrate, and a shiny reflective cathode. Light is emitted from the transparent anode direction. Using deuterium instead of hydrogen, in other words deuterated compounds, in red light , green light , blue light and white light OLED light emitting material layers and other layers nearby in OLED displays can improve their brightness by up to 30%. 

In “white + color filter method“, also known as WOLED, red, green, and blue emissions are obtained from the same white-light LEDs using different color filters. With this method, the OLED materials produce white light, which is then filtered to obtain the desired RGB colors OLEDs also have a much faster response time than an LCD. Using response time compensation technologies, the fastest modern LCDs can reach response times as low as 1 ms for their fastest color transition, and are capable of refresh frequencies as high as 240 Hz. According to LG, OLED response times are up to 1,000 times faster than LCD. 

The biggest technical problem for OLEDs is the limited lifetime of the organic materials. One 2008 technical report on an OLED TV panel found that after 1,000 hours, the blue luminance degraded by 12%, the red by 7% and the green by 8%. In particular, blue OLEDs at that time had a lifetime of around 14,000 hours to half original brightness (five years at eight hours per day) when used for flat-panel displays. 

For many, like me, lcd tv was their first experience of 42 inch tvs in 2007.  With a launch price of just 1300 euro it was significantly cheaper than either of oled tech at the time, and vastly longer life span at the time. This defined some advantages over. While its led focused on ever increasing picture brightness and longer lifespan,  OLED companies focused on picture quality while lifespan was second though at the beginning. Today we have much more efficient oled tvs with longer lifespan.

The OLED TVs that came after 2012  introduced a new generation to people who weren’t familiar with infinite contrast.  The oled  doubles as both brightness and contrast led to the significant advantage in comparison with any other lcd led tv. OLED TVS are masters of the best picture quality and the LG and SAMSUNG  was a generational defining piece of design. Devices like the LG G SERIES were  designed for a more affordable  time.

Decades later after first oled test sample we have one of most advanced  Quantum Dot OLED types by Samsung which can achieve the best possible colors and infinite contrast of oled. In this powerful new oled world, things will get even better with devolepod of new technology such a micro led. You might have noticed a decrease in price as a result, and this trend will soon make OLED TVs accessible to many more people than ever before.