OLED display: what is it? Organic light-emitting diodes (OLED) and displays based on them

Modern people spend half of their time in front of screens, which is why it is so important for them to know what advantages and disadvantages certain display technologies have. Users are constantly looking at the screens of their monitors, TVs, phones, cameras and other devices. Therefore, not only the indicator, but also the technology according to which it is manufactured has acquired great importance. The most common technology is LCD (LCD). If a TV screen is described as “LED”, then we are most likely talking about this technology. The light source in this technology is LEDs.

Differences in the design of LED LCD and OLED screens

In an illustrated article published by TrustedReviews, “OLED vs LED LCD – Which display tech is the best?” Andrew Williams reviewed the features of each of the most popular screen technologies for modern devices. Many people have heard about the excellent qualities of OLED. It's time to talk about the advantages of LCD technology.

OLED technology is characterized by significant differences from LED LCD. It is used, for example, in Samsung Galaxy smartphones and TVs such as the LG 55EC930V. Some people believe that this technology is the future. Does it actually outperform good LED LCD displays?

OLED and LED LCD. Main Difference

The main difference is that in LED LCD the pixels are backlit, while in OLED they emit their own light. You may have heard OLED pixels referred to as “emissive.” This means that the brightness of an OLED display can be controlled on a pixel-by-pixel basis. This level of control is not available in LED LCD.

Low-cost TVs and phones with LCD screens use LED backlighting that sits on the side of the display rather than directly underneath it. The light from these LEDs passes through a matrix with red, green and blue pixels, which form a picture that is understandable to human eyes.

In this type of screen, control over the brightness level is limited. In a dark room, such an LCD screen shows that some parts of the image are not completely black because light is also passing through them.

Contrast means how different black and white colors are from each other, how much brighter white is than black. In good LCD screens this ratio is 1000:1. This means that white is a thousand times brighter than black.

OLED Contrast

In OLED displays, pure black emits no light at all. Therefore, the image, for example, when watching a movie, will look unpredictable. Part of the image will stand out sharply in its brightness.

There are also Direct LED displays, where the LEDs are located directly below the panel, allowing finer control over how bright certain areas of the screen will be. This technology is used in some premium TVs.

On Direct LED TVs, the ability to control the image at the pixel level is also not available. Instead, you can dim the image brightness in certain areas of the screen. This can be a very useful feature when you're watching a 21:9 movie on a TV that has a more conventional 16:9 aspect ratio.

Can LCD compete with OLED?

Professional TV calibrator Vincent Teoh said, "LED LCD will never match OLED in terms of black level," while adding, "it is superior in maximum brightness."

For viewing content in dark rooms, the best solution is an OLED display. Such displays are good in phones. The main manufacturer of such smartphones is Samsung. Nokia Lumia phones used OLED screens at one time. Sony, Apple and LG predominantly use LCD displays in their phones.

LCD continues to dominate televisions. Tio notes that LCD will “remain its position as the dominant TV technology in the future until OLED reaches a similar price for the same size and specifications, which will not happen for at least another 5 years - if OLED is even around after this time.” for a long time".

Disadvantage of OLED technology

If OLED technology is so good, then why aren't all TVs based on it? The fact is that the production of such televisions is incredibly complex and they are expensive. Mostly OLED TVs from Samsung and LG are known. Samsung's OLED (KE55S9C), which has an incredibly high price, has a known defect - blue LEDs work less well than green and red ones. Yes, they will work for years, but for that kind of money, users would like something close to perfection.

LG managed to avoid this defect by using white LEDs and color filters above their surface, which brings the technology closer to LCD.

Advantages of LCD technology

Relatively low cost is the main advantage of LCD displays. You can find high quality LCD screens in not very expensive devices. Examples of this are the IPS panel in the Moto E. Thanks to LCD technology, relatively inexpensive TVs are possible, the price of which is more than 10 times lower than their OLED counterparts. It is possible that over time smartphone screens will also have this resolution.

The image on an LCD screen often looks sharper than on an OLED screen at the same resolution. And the problem is not only the different operating times of LEDs of different colors. The level of light output from them also differs. While LCD screens are characterized by uniform colors (red, green and blue subpixels), OLED displays display them more… “dynamically.”

Sony demonstrates contrast difference between LED LCD and OLED

For example, instead of using three constant subpixels, the Galaxy Note 4 has small dots of red, blue and green that effectively form two pixels. They differ in shape - red and blue are diamond-shaped, and green are small ovals.

This is called PenTile layout and makes the screen image appear somewhat uneven. However, in the newest phones this effect is gradually disappearing. However, OLED remains a more complex and less mature technology than LCD.

Are the advantages of OLED technology significant enough for the incredibly high price that characterizes screens based on it?

Electronic devices with displays have become an integral part of our daily lives, requiring more and more attention. The eyes of millions of people are drawn to the screens of monitors and televisions, tablet PCs and smartphones, photo and video cameras every day. Some work, some play, but everyone wants to see a high-quality image on the display.

Over the past years, LCD technology with LED backlight has held the leadership in the production of matrices. However, OLED technology, based on the ability of organic light-emitting diodes to emit light, continues to “tread on its heels”. What are OLED displays and what prevents them from competing on equal terms with LCD screens?

Operating principle and manufacturing technology

Organic light-emitting diode, or OLED for short, is a semiconductor device made from organic compounds that emit visible light when electrical current is passed through. In a single copy, an organic LED is of no practical interest. Therefore, they are combined into matrices to create information display devices.

OLED technology is a process of creating a thin-film structure on which several layers of polymers with different conductivities are applied. The figure shows a vertical section of the OLED structure in a two-layer interpretation. Here, two polymer layers are located between the electrodes (anode and cathode), to which a voltage of the appropriate polarity is applied. In this case, the upper (emissive) layer is filled with electrons emitted by the cathode, which rush to the boundary with the lower (conducting) layer. At the same time, the conductive layer receives a positive charge from the anode, directing holes to the boundary with the upper layer. The boundary of two polymers resembles the p-n junction of a conventional semiconductor, where the recombination process occurs. But in this case, charged particles recombine in the emission layer, which is achieved due to the higher speed of holes in organic structures. As in conventional LEDs, the loss of energy by an electron is accompanied by the emission of photons in the visible wave spectrum. For this reason, the top layer is called emissive.

An organic LED emits light only when the polarity of the supply voltage is observed. If a reverse voltage is applied to the electrodes, then electrons and holes will not recombine. The material for the anode is usually a film of transparent indium oxide, and the material for the cathode is aluminum or calcium.

Main directions

Independent research on the creation of OLED matrices among scientists from different countries contributed to the emergence of LED displays that differ in type and purpose. Each technology has its own practical advantages and, therefore, development prospects.

TOLED (Transparent OLED) – positioned as a transparent organic light-emitting device. Technologically, it is possible to set any direction of radiation, including two-way. TOLEDs are distinguished by a high-contrast image and transparency of the film when turned off, which significantly expands the scope of their application.
FOLED (Flexible OLED) – is implemented by fixing an organic film between flexible electrodes. The electrodes can be either the thinnest aluminum foil or a transparent film borrowed from TOLED. Thus, it is possible to create flexible transparent screens with a wide range of capabilities, placing them on the windshield of cars and airplanes. There are already TVs with curved OLED displays on sale.
SOLED (Stacked OLED) is a structure of vertically stacked organic light-emitting diodes. Each subpixel (blue, red, green) is located on top of each other, which allows you to increase the screen resolution several times. An undeniable feature of SOLED is its color fill factor of 100%. This means that when the screen color is set to red, all pixels will glow only red. Enabling a similar mode on displays with a horizontal structure will turn off the blue and green pixels. As a result, so-called gaps will appear, which will become noticeable on large screens.

It is obvious that the subsequent development of OLED technologies consists of the combined implementation of these techniques and the production of flexible transparent high-contrast displays.

A separate line is worth highlighting OLED panels with white light. Their practical implementation is simpler, since it eliminates the need to create separate pixels and control matrices. Using a phosphor you can set any shade, and by changing the current you can adjust the brightness. Large panels can be used as economical ceiling and wall lamps.

Main differences between OLED displays

The main difference between OLED and LCD displays is the absence of a backlight unit. Organic LEDs emit light on their own and do not require an additional light source to form an image. In turn, the image quality of an LCD screen directly depends on the type of backlight and, despite the replacement of fluorescent lamps with more compact LEDs, it is impossible to do without it. Even the thinnest LED backlight consists of SMD LEDs, light guides, reflectors and their attachment points, which naturally affects the thickness, weight, image quality and reliability of the product.

In addition, OLED matrices are credited with lower power consumption, again due to the lack of backlighting. However, this difference is not so significant. To illuminate each organic LED, current must be passed through it. As a result, a 55″ OLED TV consumes about 100 W, which is comparable to the consumption of a similar LCD TV.

An important characteristic of any display is the viewing angle. In OLED screens, this parameter has been brought to perfection, which means that you can look at it from any side, top and bottom, without deteriorating image quality. In LCD panels, a similar result was achieved on IPS matrices. However, it was not possible to completely get rid of distortions.

The contrast of OLED displays is several times higher than that of liquid crystal counterparts, which is explained by two factors. Firstly, there is no additional lighting. Secondly, a switched-off organic LED does not emit anything, which means it is perceived by the eye as an absolutely black dot. The contrast ratio of currently produced televisions is 10,000:1. According to the developers, this is far from the limit.

The OLED display is 1000 times faster than LCD. This is evidenced by a response time of approximately 10 μs. Comparing this value with the capabilities of the human eye, we can safely say that there is no inertia when watching the most dynamic videos.

The brightness of each Organic LED depends on the magnitude of the forward current. By controlling the pixel current, it is possible to achieve the required brightness without loss of quality, which was impossible to implement in LCD technology. Working with an OLED monitor is equally pleasant both at night and in sunny weather. In theory, the brightness of an OLED matrix can exceed 100 thousand cd/m2. But in this mode, the service life of LEDs is sharply reduced. Therefore, in practice, the brightness is still limited to 1000 cd/m2.

Advantages and disadvantages of OLED technology

Based on the previous section, there are several positive aspects that make OLED displays superior to all previous technologies:

Less weight and size, which is achieved due to the small thickness of the matrix;
- low energy consumption, which will further decrease in the future;
ideal viewing angle;
- lack of backlight;
- contrast, brightness and response time are several orders of magnitude better than LCD;
- the ability to create flexible and transparent screens that will operate stably over a wide temperature range.

Like any technological process, the production of OLED matrices has disadvantages that significantly hinder their mass production. Moreover, the main limiting factor does not depend so much on the imperfection of technology, but is determined by purchasing power.

The second disadvantage is the short continuous operation time of organic LEDs of some colors. But this problem has already been successfully solved, as evidenced by the serial production of laptops and TVs with OLED matrix by world-famous companies.

The disadvantages include the screen burn-in effect, which occurs due to prolonged display of a static image. The effect is reminiscent of the appearance of a false picture on CRT and plasma monitors. To prevent LEDs from burning out, new matrix models feature a dynamic shift of color pixels that is invisible to the eye.

OLED technology will be improved and refined for several more years, which today can also be called its negative side.

Prospects and scope

There is no doubt that OLED technology will dominate the electronics market. But so far this innovative way of displaying information has to overcome great difficulties associated with the need for large commercial investments. For this reason, some companies have significantly reduced costs or even stopped funding research to create their own OLED matrices. For example, Sony relied on the production of LCD TVs with 4K resolution, considering this approach to be economically justified.

Among those who are not going to give up and continue to improve the quality of OLED displays, the favorites are South Korean LG and Samsung. In the near future, these companies expect to reduce the cost of OLED matrices and become their main suppliers for other manufacturers of electronic equipment.

Already now we can observe the active promotion of “smart” gadgets with small screens. OLED watches, smartphones, netbooks find their buyers, for whom an overpayment of 20-30% is nothing compared to a super high-quality image. The retail price of a 55˝ OLED TV is currently 2-2.5 times higher than an LCD TV with the same parameters.

Time will tell how quickly OLED can take over. One thing is certain - the OLED display market will progress every year.

War of Thrones: OLED vs. LED/LCD

To understand the disadvantages and advantages of these two technologies, let's briefly compare OLED and LCD/LED displays.
The brightness of both types of matrices is better than that of plasma, which results in less loss of picture quality when viewed on a sunny day. Individual parts of the image on OLED can be brighter than on LCD displays, while the latter outperforms its competitor in terms of brightness of the entire screen backlight (which is actually not that important when viewing).

OLED screens are distinguished from any other by amazingly deep blacks, since one of the features of this type of matrix is the ability to completely turn off individual pixels to obtain perfect blacks.

Due to the fact that OLEDs are superior to their rivals in the brightness of individual areas of the screen and the depth of black, they also provide a more contrasting picture (at the moment, displays of this technology have no equal in this indicator). This is important because high contrast makes the image more realistic.

As for blurring of moving objects, this problem is familiar to both LCD/LED and OLED displays. Screen refresh rate is important in reducing blur. OLED screens and all 4K TVs today have an actual refresh rate of 120Hz (marketing gimmicks aside). This figure is 60 Hz in cheaper LCD/LED displays, and some 1080 pixel LCD screens have refresh rates of up to 240 Hz.

The picture quality of liquid crystal matrices deteriorates significantly depending on the angle at which the viewer looks at the screen. If we talk about OLED matrices, they have a larger viewing angle than their competitors, although they cannot compare in this with plasma TVs.

The screen uniformity of OLED is much higher than LCD/LED, although it is inferior to plasma, but at present it is too early to draw conclusions - the technology does not stand still at all.

If we talk about energy consumption, then in the case of OLED this figure directly depends on the brightness of the screen: the brighter it is, the more energy is needed. Therefore, watching a dark film will be cheaper than a colorful cartoon. In contrast, LED power consumption depends on the screen backlight settings - the weaker the backlight, the less energy the TV consumes. By setting this indicator to the minimum settings, you will save more on energy consumption with LED displays. However, both of these technologies do not consume so much energy to call this an important point when choosing a TV.

OLED prices are still steep, as happens with all new technologies, but developers promise to reduce them in the coming years. So most of us will have to wait to see OLED displays.

As for the service life, this indicator is quite blurry in the case of OLED. According to LG engineers, TVs with new generation displays will be no less durable than LCD/LED screens. In fact, all this is not confirmed by specific figures, and in any case, the lifespan of the TV does not depend on the technology used, but on the specific instance - it’s like a lottery, if you’re lucky, the TV will serve you for a long time.

Screen burn-in is a problem primarily found in plasma displays. As for OLED, it remains unclear how strongly this feature will manifest itself on these screens. Theoretically, dot burnout can occur since the pixels themselves emit light and can be damaged due to prolonged increased brightness of the radiation. Liquid crystal displays are unfamiliar with this, although the problem of dead pixels remains relevant. In any case, do not leave the TV on with a static image for long hours - it will last you longer, and in the case of plasma and OLED, it will protect you from burning out the screen and seeing the imprint of one or another fragment.

Arms Race: Samsung vs LG

Currently, only two companies are actively selling TVs based on the OLED matrix: Samsung and LG. Only in September of this year did Panasonic join them: the company presented its first and currently only model of a TV with an OLED matrix - again, manufactured by LG.

The OLED displays of these two South Korean giants have fundamental differences in architecture, which affects not only the image quality, but also the cost of production, and therefore the price of TVs.

Samsung makes matrices using subpixels of three colors from the standard RGB model: Red, Green and Blue (Red, Green, Blue), which form each pixel. This technology was used by the corporation to create Super OLED TV and the first small displays. Its problem is that it does not scale well, which leads to high production costs.

And here displays from LG differ from competitor products by a completely different architecture, which is based on not three, but four colors. This technology is called WRGB or WOLED-CF: in addition to the usual three colors, a white subpixel is added - in this case, color filters are located on top (RBG and W). WRGB technology for OLED displays was developed by Kodak engineers, and then the rights to it were purchased by LG Display. This technology, according to experts from LG, is much easier to scale, and therefore the production of such screens is cheaper. This solution is used in all LG TVs, both with a curved screen (for example, the more affordable LG 55EC930V model with FullHD resolution) and flat screen (LG 55EF950V with Ultra HD 4K resolution).

OLED displays can be quite flexible, so engineers use this matrix property to create curved screens. As a rule, the bending radius of the matrix is quite large (several meters), so this is more of a fashionable new feature in TV design than a solution that provides significant viewing benefits.

In 2012, LG sued Samsung for violating LG Display's patent rights to OLED panel technology, but both South Korean companies later agreed to a settlement, deciding that cooperation in the development of new technologies was the best solution.
This summer, LG Display held a press conference to celebrate the company's 20th anniversary, where it was announced that LG Display's focus would henceforth be exclusively on OLED displays. Over three years, it is planned to invest about $8.5 billion in expanding the production of screens based on this technology.

You can read more about the technology itself on Geektimes.

Prospects for the development of OLED

Whatever one may say, at the moment there is only one factor against the widespread use of OLED - the high price compared to models created using competing technologies. However, according to engineers, it should become less “biting” in the coming years, since LG and Samsung are working hard to reduce the cost of technology and production. One cannot argue with the fact that today LCD-based TVs still occupy leading positions in the market - they provide fairly good picture quality, are cheap to produce and, as a result, can boast very reasonable prices. But OLED technology has already made itself known and found adherents, since these displays provide the best possible image quality at the moment (which is mainly due to the amazing contrast), and in this they have no equal.

This summer Samsung Display Co., Ltd. introduced the world's first transparent OLED display with a mirror effect. The company is positioning this development as a solution for stores that will help customers try out makeup, try on an outfit or jewelry without leaving the screen, which can serve as a kind of interactive showcase that attracts customers. In this prototype, Samsung engineers combined an OLED display with Intel Real Sense technology to enable human interaction.

OLED displays have a great future not only due to their amazing picture quality, but also due to parameters such as thinness and flexibility. OLED displays were initially used for small phone screens and smart wearable devices, then expanded to TV screens. This technology is also of great interest for the fashion world - it is based on the creation of interactive photonic textiles, which in the future can take the modern fashion industry to a new level

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We've been waiting for OLED screens in laptops for many years. And at this year's CES, several companies have already announced future laptop models. Now it has become clear who will produce these panels.

Samsung has unveiled what it calls the very first 15.6" 4K panel. The screen will provide “superior HDR color and high outdoor visibility,” said Yoon Jae-nam, marketing director of Samsung Display.

Each pixel has its own color source, allowing you to create truly black areas. Thanks to this, the screen received DisplayHDR True Black certification. It is bright enough to comply with DisplayHDR 600, and the color gamut is 100% of the DCI-P3 palette - 34 million colors. At the same time, it is lighter, thinner and consumes less energy than LCD.

However, OLED does have disadvantages. The main one is burn-in, which affects the limited service life of the display and picture quality. Samsung will begin production of OLED panels for laptops in mid-February. It was previously reported that they will find a place in the Dell XPS 15, Alienware m15 and G 15, as well as the HP Specter x360 OLED 2-in-1.

Japan is already developing an 8K display for tablets

January 3

If you love ultra-high-resolution displays, then Semiconductor Energy Laboratory has great news. The company is developing 8K OLED displays that will find a place in the laptops and tablets of the future.

Work is underway on screens with a diagonal of 8.3" and 13.3". Both have a resolution of 7680x4320. This means that the smaller display, which would be ideal for tablets, will have an astonishing 1062 ppi density. The larger screen, designed for laptops, will have a 663 ppi screen, which is almost three times larger than the MacBook Air Retina.

Both panels are made using semiconductor technology using C-axis indium gallium zinc oxide crystals, or CAAC-IGZO.

As for the characteristics, the 8.3” panel will be able to operate at a frame rate of 60 Hz, while the larger 13.3” panel can reach 120 Hz.

Since Semiconductor Energy Laboratory does not have its own production, it cannot yet predict the start of mass production of panels. Now it is looking for production partners for these purposes.

Finalwire has updated AIDA64 to version 5.98

September 20, 2018

FinalWire Ltd. has again updated its popular diagnostic and testing utility AIDA64.

In version 5.98, the utility received support for upcoming video accelerators from NVIDIA and AMD, and support for recent updates to the Windows operating system and some LCD displays was also introduced.

The full list of changes in AIDA64 version 5.98 is given below:

Added support for Windows 10 October 2018 Update.
Optimized VESA AES benchmark.
Added EVGA Z10 LCD support.
Improved support for ARM systems
Added support for Thermaltake Riing Plus sensor.
Improved support for motherboards based on AMD B450 and X chipsets
Added support for Corsair H80i Pro, H100i Pro, H115i Pro, H150i Pro sensors.
Added support for Matrix Orbital EVE LCD and OK OLED displays.
Added support for Vulkan1, WDDM 2.4.
Detailed information about GPU AMD Radeon RX 560X, Radeon RX 570X, Radeon RX 580X.
Detailed information about NVIDIA GeForce RTX series GPUs

As before, the utility is offered in 4 editions, You can buy them on the developer’s website.

Apple is developing MicroLED screens

March 24, 2018

The next round of rumors coming from the West says that difficulties await Asian manufacturers of OLED displays, since Apple has decided to produce screens on its own. We are talking about MicroLED type screens.

According to Bloomberg, the Cupertino company is developing its own MicroLED displays at a secret plant in California. The development is led by Lynn Jung, responsible for screen technologies for the iPhone and Apple Watch.

The move could have a big impact on Asian screen manufacturers. MicroLED technology is a new development that several companies are interested in. Screens made using this technology are thinner, brighter, less power-hungry and more reliable than OLED, which is common on many mobile devices.

But it's not all bad for Asian companies. While Apple is in the early stages of creating displays, MicroLED technology in general is quite complex. Apple wants to use new screens in wearable devices, so they are unlikely to appear in smartphones in the next 3-5 years.

Sharp will start producing OLED panels

February 1, 2018

In the first quarter of 2018, Sharp will begin producing OLED panels for smartphones, and the first solutions on the market with Sharp OLED screens will go on sale in June or July.

According to the company's executive director Dai Zen-Wu, Sharp is already ready for mass production of OLED panels, and deliveries to the company's customers will take place according to the previously planned schedule.

Thus, Sharp will become the first Japanese manufacturer to launch the production of OLED panels for smartphones. The company is now part of Foxconn and is trying to enter the supply chain for the Apple iPhone X, for which screens are currently supplied only by Samsung Display.

The Japan Times reports that at a cost of $515 million, Sharp could produce the screens at two factories. One of which will produce small and medium-sized displays for phones and laptops, and the second will focus on TVs, where LG dominates.

ASUS releases ProArt Pq22UC portable OLED monitor

January 12, 2018

Amid the growing popularity of laptop computers, Asus has released a new ProArt PQ22UC monitor with UltraHD resolution. In addition to 4K resolution, the display boasts an OLED panel with HDR support on a 21.6” diagonal screen.

Since the monitor is intended for professionals, it has 10-bit color and covers 99% of the DCI-P3 palette.

Portability is expressed in a collapsible design, a weight of about 1 kg, and the absence of the need for an outlet. Instead of a regular plug, it has a USB Type-C connector for power supply. A second USB Type-C or micro HDMI is used to transmit the video signal.

The main disadvantage of the monitor will be its price. Of course, professionalism and portability come at a cost, but costing over $3,000 for a 22-inch display is a bit much. It is unknown when the Asus ProArt PQ22UC will go on sale, but most likely it will happen in the 1st quarter of 2018.

LG Display has created an 88” OLED display

January 4, 2018

LG Display has introduced its new 88” OLED display with 8K resolution, which is a record resolution for OLED panels.

Previously, the largest OLED screen was 77” in size, but its resolution was 4K. So far, the company has remained silent about the final products where it will use the new panel, and has said nothing about the price.

LG's main competitor, the Korean Samsung Display, long ago switched its focus from OLED TVs to QLED, which made LG the largest manufacturer of OLED screens. The company is also trying to move into the production of OLED displays for smartphones, where Samsung completely dominates.

At the same time, LG associates its future with OLED, since the company decided to open its first plant outside of Korea - in Guangzhou, China, and this deal was approved by the South Korean government. So LG Display will soon break other records.

Samsung hopes to release a foldable Galaxy Note next year

September 23, 2017

Samsung's new flagship, Galaxy Note 8, released in August, is showing excellent sales. Now the company hopes to release the first foldable phone next year, reports the Associated Press.

The future tablet phone will have a folding screen, and the device will be released under the Galaxy Note brand. Dongjin Koh, president of Samsung's mobile business, told reporters during a news conference that the company is now facing a number of difficulties, and if they are not resolved, the release will have to be postponed.

It is clear that the company is profiting from the use of infinity screens, which are achieved using flexible OLED panels. This design is incredibly popular, and phones with it sell like hot cakes. However, Koch stated: “When we can confidently avoid certain problems, we will release the product... We dig deep to find different problems that we need to avoid. After all, we don’t want to just make a lot, sell a lot and calm down. We want to hear that Samsung has made a very good product... We have a plan to introduce foldable displays on our roadmap.".

Let us recall that Samsung first presented a prototype of a folding AMOLED display in 2012, calling it Youm. Last year, the company published a patent for a foldable phone similar to a clamshell.

Apple wants to produce OLED screens itself

July 27, 2017

Starting this year, Apple decided to abandon the use of LCD screens in its smartphones, replacing them with brighter and more contrasting OLED displays.

The iPhone 8 is already expected to have an OLED screen, which will be manufactured by Samsung. However, rumors have emerged in the technology world that Apple is worried about becoming once again dependent on Samsung, and therefore has decided to produce OLED panels on its own. In this case, the company will need many such screens.

South Korean resource ET News reported that Apple has already purchased several chemical deposition units that are used in the production of OLED screens.

Other sources, in particular Digitimes, claim that such a move by Apple will change the balance of power in the equipment market for the production of OLED panels. The fact is that Samsung and LG, the only significant manufacturers of OLED screens, use chemical deposition units from Canon Kokki, but Apple decided to use equipment produced by Sunic System.

LCD panel manufacturers speed up production of 18:9 screens

July 7, 2017

Manufacturers of LCD panels and related components report high demand for 18:9 aspect ratio screens, which are being ordered by smartphone manufacturers for the second half of 2017.

Following Samsung Electronics and Apple, Chinese smartphone makers including Huawei, Oppo, Vivo and Xiaomi Technology are also expected to launch models with 18:9 edge-to-edge screens in the second half of the year.

However, instead of OLED panels used by market leaders, Chinese manufacturers will prefer 18:9 TFT-LCD screens for all device models, which is caused by a shortage of OLED screens.

The main manufacturer of screens for Samsung and Apple smartphones is currently Samsung Display. However, all the screens they produce are fully purchased by two industry leaders. Due to this, Chinese manufacturers are forced to purchase 18:9 TFT-LCD panels from AU Optronics (AUO), Innolux, Chunghwa Picture Tubes (CPTs), HannStar Display, BOE Technology or even Samsung Display. And although TFT screen manufacturers must upgrade their production to produce 18:9 screens, the quality of the screens themselves and their characteristics are high enough to be installed in mid-range phones.

Liquid crystal display ( LCD-display, LCD; liquid crystal indicator, LCD; English liquid crystal display, LCD) - a display based on liquid crystals, as well as a device (monitor, TV) based on such a display.

LCD monitor screens (Liquid Crystal Display) are made of a substance (cyanophenyl) that is in a liquid state, but at the same time has some properties inherent in crystalline bodies. In fact, these are liquids that have anisotropy of properties (in particular optical ones) associated with order in the orientation of molecules.

Their main feature is the ability to change orientation in space under the influence of an electric field. And if a light source is placed behind the matrix, then, passing through the crystal, the flow will be colored in a certain color. By changing the electric field strength, you can change the position of the crystals, and therefore the visible amount of one of the primary colors. Crystals work like a valve or filter. Controlling the entire matrix makes it possible to display a specific image on the screen.

Liquid crystal materials were discovered back in 1888 by the Austrian scientist F. Renitzer, but it was only in 1930 that researchers from the British Marconi Corporation received a patent for their industrial use.

At the end of 1966, RCA Corporation demonstrated a prototype LCD monitor - a digital clock. Sharp Corporation played a significant role in the development of LCD technology. It is still among the technology leaders. The world's first calculator CS10A was produced in 1964 by this corporation. In October 1975, the first compact digital watch was produced using TN LCD technology. In the second half of the 70s, the transition began from eight-segment liquid crystal displays to the production of matrices with addressing of each point. So, in 1976, Sharp released a black-and-white TV with a 5.5-inch screen diagonal, based on an LCD matrix with a resolution of 160x120 pixels.

One of the highest quality types of LCD matrices is IPS. It is IPS technology that dominates in mobile devices, as it has good color reproduction and, which is especially important for smartphones, good viewing angles.

The operating life of the LCD TV (display) is about 60,000 hours.

LED screen ( LED screen, LED display) is a device for displaying and transmitting visual information (display, monitor, TV), in which each point - pixel - is one or more semiconductor light-emitting diodes (LED).

LED - this is what is now commonly abbreviated as a liquid crystal (LCD) panel with light-emitting diode (LED) backlight. Not so long ago, fluorescent lamps (CCFLs) were used to backlight the LCD matrix, but today they have been completely and irrevocably replaced by LEDs. The matrix works in the light. Essentially, each RGB pixel represents a “shutter” (actually a filter) for the light emitted by the LEDs. By the way, a very interesting option is when the TV uses “local” backlighting, that is, many LEDs are installed behind the matrix and can illuminate only a certain area. Then a high contrast ratio is achieved in one frame, but the first such models literally “came in spots.” However, today most LED TVs have edge lighting, when the diodes are located on the sides (at the end). This design allows us to make extremely flat, energy-efficient and lightweight video panels.

Most often, the service life of LED TVs is in the range from 50 to 100 thousand hours.

Organic light-emitting diode (abbr. OLED) is a semiconductor device made from organic compounds that effectively emit light when an electric current passes through them.

The basic display technology is based on placing a carbon-based organic film between two conductors that pass an electric current, causing the film to emit light.

The main difference between this technology and LED is that the light is emitted from each pixel individually, so a bright white or colorful color pixel can be next to a black pixel or a completely different color without them affecting each other.

This distinguishes them from traditional LCD panels, which are equipped with a special backlight, the light from which passes through a layer of pixels.

Unfortunately, OLED pixels differ not only in color, but also in a number of other characteristics - brightness level, service life, on/off speed, and others. To ensure relatively uniform characteristics of the screen as a whole, manufacturers have to resort to a variety of tricks: varying the shape and size of the LEDs, placing them in a special order, using software tricks, adjusting the brightness using PWM (that is, roughly speaking, pulsation), and etc.

Moreover, the technologies for implementing the matrices themselves differ slightly. So, LG uses a “sandwich”, while Samsung uses a classic RGB scheme. OLED can be bent, seemingly without any special consequences. Therefore, concave TVs were also built based on this technology.