OLED (Organic Light Emitting Diode) is a display technology used in televisions, mobile devices, and other electronics. OLEDs are made of organic materials that emit light when an electric current is passed through them. They are thinner, more efficient, and have better image quality than traditional LCDs (liquid crystal displays).
History of OLEDs
The first OLED was created by General Electric scientists in 1987. However, it was not until the mid-1990s that the technology began to be commercialized. The first commercial OLED product was a small display for digital watches, which was introduced by Seiko Epson in 1999. Sony released the world’s first OLED television in 2007. Samsung and LG followed suit with their own OLED TVs in 2010.
How Do OLEDs Work?
An OLED is made up of two layers of organic material sandwiched between two electrodes. When an electric current is applied to the electrodes, it causes the organic molecules to emit light. The color of the light depends on the type of material used in the device. Red, green, and blue are the most common colors used in displays because they can be combined to create any other color.
It’s also possible to make white OLEDs by using a single layer of material that emits all three primary colors simultaneously. WhiteOLEDS are often used as backlights for LCD screens because they provide even lighting and use less power than traditional backlights such as CCFLs (cold cathode fluorescent lamps).
An important property of OLEDs is that they can be very thin – as little as 2 or 3 nanometers thick (a human hair is about 80,000 nanometers wide). This makes them well-suited for use in flexible displays and portable devices such as smartphones and smartwatches where weight and space are at a premium.
How AreOLED Displays Made?
Making large area flat panel displays typically starts with a glass substrate onto which rows and columns of pixel-sized conducting electrodes are sputtered (deposited from a vapor). One electrode will be deposited on top of another with an insulating spacer layer between them; this structure forms what’s known as a bottom gate/top conductor configuration sandwich transistor architecture typical for TFT LCD production processes but adapted here for amorphous silicon TFT backplanes driving LTPS(low temperature polysilicon) or oxide semiconductor CMOS frontplane active matrixes connected to each pixel’ s respective row/column electrode pairings.. After deposition , these layers must then go through patterning steps using photolithography , etching , etc .to form discrete transistor elements comprising source/drain regions , gate dielectric spacers ,and so forth down to individual pixel areas whereupon emissive polymer materials can finally be deposited & processed into electroluminescent light -emitting diodes( LEDs )or phosphorescent dopants injected into host emitting polymer matrices .. Such processing generally falls under solution -processing techniques like spin -coating & inkjet printing given their relative compatibility with monomeric /oligomeric molecular species . More specifically ,conjugated polymer chains need only be dissolved within appropriate solvent systems prior to being deposited from solution across desired areas upon suitable substrates ;this stepwise process allows for much greater design flexibility over conventional solid state doping methods while also yielding films with excellent film uniformity over large areas . As we shall see next ,the choice( s )of conjugated polymer & solvent system ultimately dictates many key optoelectronic properties like color emission wavelength( s ),efficiency /luminance output capability ..etc