QD-What is the display?-Byline Network

QD-display, which Samsung Display is promoting as its future flagship business, is another type of OLED panel. OLED is actually a general technical term, but Samsung Electronics and Samsung Display are somehow reluctant to use this term because LG Electronics has become a representative of large OLED panel production. However, the time will come when Samsung will also have to produce large-sized OLEDs, and QD-display is offering an alternative.

Since the QD-display can be interpreted as a’display using quantum dot technology’, there is a problem that it is used in several panels. QLED TVs that use quantum dot film and LED light sources for LCD TVs have already used the QLED name, making the use of the name of QD-display obscure. In principle, QD-display should mean all of QD-LCD, QD-OLED, and QD-LED, and QD-LED with the highest technical completion should bear the name of QLED.

QD-LCD is currently Samsung Electronics’ flagship TV, QLED TV. The LED light source is placed under the LCD panel, and good color is realized through the quantum dot film layer.

QD-LED is a bit more future technology. Quantum dot material is put in the light emitting layer itself to emit light. Since the light source and color filter are combined, the color filter is not used. Even with the same quantum dot material, if the particle size is different, various wavelengths of light are generated, resulting in multiple colors. However, it is still difficult to deal with quantum dot materials at this level, so the method that Samsung Display will propose in the future will be QD-OLED, which is an intermediate form between QD-LCD and QD-LED.

Source = Samsung Display

QD-OLED emits blue light among RGB colors, and green and red are implemented with color filters. Blue LED among RGB is used as the light source, and green and red can also be emitted by controlling blue LED through quantum dot material. Compared with LG Electronics’ WOLED, the number of color filters is reduced by one. Overseas, this method is sometimes referred to as a QD-OLED hybrid.

Among the three colors, blue is used as a light source because of the energy difference. Among the visible light areas, blue is the most energetic, so it is advantageous for increasing luminance or converting to other light and color. Quantum dot materials need to receive higher energy than their own particles to reveal their natural color, so they use blue light with the highest energy.

Source = Samsung Display

The advantage is that it has a wide color gamut satisfaction, and is relatively free from burn-in problems caused by burning organic materials by blue light. The reason is that the quantum dot material is composed of inorganic materials, not organic materials.

As it is an LED product, not an LCD, it is free from light leakage (halo, blooming) that occurs in LCD. The light can be turned off in the black part. Like WOLED, HDR performance can be improved by turning off the light when expressing the black part.

However, it is being evaluated as having disadvantages, in fact, there is a problem of how much green and red can be distinguished by consumers, and due to its simple structure, in theory, it should be produced cheaper than WOLED. There are no problems.

The reason Samsung Display is focusing on QD-OLED is that the growth engine of large panels, especially LCDs, is falling. LCD growth is slowing down due to the inflow of cheap products from Chinese manufacturers. However, Samsung Electronics, the largest customer of Samsung Display, still introduced Neo QLED, an LCD-mini LED product, as its flagship product in 2021, so QD-OLED TVs will not appear under the name of Samsung Electronics for the time being. It is only possible in 2022 at the earliest. Panel orders from other manufacturers such as Sony are still under consideration, and Sony is also introducing mini LED (LCD) TVs as its flagship TV in 2021. This is because the TV maker’s point of view is the mini LED + quantum dot film LCD TV, which guarantees a certain degree of high color reproduction, is attractive in price, and allows moderately delicate light adjustment.

QD-OLED is a product that can replace mini LED or OLED in monitors and TVs as it has a special strength in high color reproduction. However, this can only be known after being judged by consumers and experts after launch. With the emergence of QD-OLED products, the OLED confrontation between LG Electronics and Samsung Electronics occurs once again, increasing consumers’ choices, and it is ideal to be able to purchase good products at low prices.

Written. Byline Network
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