The days of tube televisions already feels like a distant memory. In the 21st century, glorious high-definition units have replaced them. These marvels of technology possess a fraction of the weight and thickness, yet their visuals are exponentially more stunning. The best of them use organic light-emitting diode (OLED) technology. Here’s what you need to know about how OLED works.

OLED Defined

OLED tech

Image via Flickr by LGEPR


The OLED is a solid-state device, so it has no moving parts. Its explicit purpose is to generate light electronically through semiconductors, and it requires virtually no space to do so. The average OLED is infinitesimally small, roughly 100 nanometers thick, which is orders of magnitude thinner than a human hair. In order for an OLED to build the proper amount of light, it must rest between a pair of electrodes which power it.

Technical details aside, the applications of such a tiny product are obvious. The miniscule size of an OLED allows television manufacturers to add clusters of these devices, which are almost insignificantly small and light, but offer dazzling detail and colors, to a television screen. They’re the reason why even large-screen HDTVs are so thin and lightweight, yet have extraordinary picture quality.

How OLED Works

There are six parts to an OLED: the anode, cathode, substrate, organic layers, conductive layer, and the emissive layer.

The magic word for the operation of an OLED is electrophosphorescence. This is a form of phosphorescence that transpires thanks to an electric charge. There are several steps to the process. The initial stage begins when the attached power supply provides voltage, which activates the solid-state device.

Next, the new electric current relays to the attached anode and cathode via the organic layers and conductive layer. This relay system activates electrons. The activated electrons discover electron holes and release energy to fill that void. This step is effectively the release of light. Since the OLED is emitting light, the system needs an identifier to determine the color of this new illumination. That’s why the emissive layer is crucial. A manufacturer can lace the layer with various organic films. The one that light passes through becomes the display color.

The final step is also important. The manufacturer controls the brightness of the color by providing more voltage when a higher intensity of color is needed. So, the voltage dictates the brightness.


The benefits of OLED over earlier HDTV standards such as LED are obvious. It’s lighter, brighter, and crisper. Manufacturers such as LG and Samsung use OLED in their best units because they offer the best performance. They don’t require backlighting like LCD TVs, and they require less power due to their solid-state nature. That means OLEDs are more environmentally friendly, and they’ll also save you money on your annual electric bill.

OLED is the best TV technology in place today. It provides the best bang for the buck as well as the best picture. Now that you know how it works under the hood, you can understand why.

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