Introduction to OLED Technology & Its Pros/Cons

OLED is a flat panel display technology that has been developed for TV, computer monitors, smartphones, and tablets. OLED stands for Organic Light Emitting Diode, producing light by passing an electric current through a thin layer of organic material. This results in a high contrast ratio, wide viewing angles, and low power consumption compared to other display technologies like LCD. It is also lighter due to not needing a backlight, which is crucial in handheld devices.

What is an OLED?

OLEDs are thin, light, and can be built to be flexible. They are made of organic layers. The materials used in OLEDs allow them to be transparent or opaque, depending on how the device is built. Unlike other displays, OLED displays do not require backlighting because they produce their own light when an electric current is applied.

This material emits color instead of relying on backlight technology in LCD displays. So not only does this process result in better contrast ratios than traditional screens like LCDs, but it also results in a more energy-efficient screen. Interestingly, the power consumption is proportional to the number of pixels that are lit up. Therefore, the user interface designer can impact the battery life tremendously. In LCDs, the backlight is the primary source of power consumption and has to be on across the whole screen for anything to be visible.

PMOLED & AMOLED

PMOLED and AMOLED are two types of OLED displays. PMOLED stands for “passive matrix organic light emitting diode,” meaning it's a passive matrix display with an organic material layer. This is the type of display used by older digital watches (such as Fitbit Charge 4 and Fitbit Alta). AMOLED stands for “active-matrix organic light-emitting diode,” meaning an active electronics layer is underneath the OLED layer. This layer acts as a memory, controlling which pixels are turned on and how brightly they are lit.

PMOLED displays use an external semiconductor chip to control which pixels are lit. This limits the size of the display to around 320 by 160 pixels.

AMOLED displays also have better color reproduction than their PMOLED counterparts because they can be tuned to achieve different levels of color at each pixel rather than offering a few levels like the older technology allows. Many PMOLEDs are built as monochrome displays.

Advantages & Disadvantages of OLED

Advantages:

• OLEDs use less power than LCDs since they generate light directly.
• OLEDs are very thin and lightweight, making them ideal for portable devices. OLEDs use fewer layers than LCDs, making them thinner and lighter without sacrificing performance or battery life.
• OLEDs have better viewing angles and contrast ratios than LCDs do; they're closer in performance to CRT monitors when it comes to color accuracy at various angles in front of you.
• OLED technology has a very wide operating temperature which can go -40~80°C. Typically for LCDs such as TFT, we have -20 ~70°C; in some exceptional cases, we have -30°C~80°C.

Disadvantages:

• The lifespan of an OLED panel used to be significantly shorter than that of a traditional TFT LCD panel, but recent advances are narrowing the gap. This is due to the individual organic materials used in each pixel being less stable over time and in the presence of humidity than their inorganic counterparts.
• High temperatures decrease OLED lifetime. You might need a custom solution if your OLED application needs to work constantly in a high temperature, like 50, 60, or 80°C.
• AMOLEDs are more expensive than LCDs.

Applications of OLED

OLEDs are suitable for almost all applications, small ones like portable devices such as watches, phones, and laptops, and bigger ones like TVs, computer monitors, and digital billboards.

However, OLED has a limited lifetime. This means that if you want the display to last for many years, you may need to find another display technology.

Conclusion

OLED is an exemplary display technology, but there are some drawbacks. OLED displays have many advantages over traditional LCDs, like higher contrast ratios and better viewing angles. However, they also have disadvantages, such as shorter lifetime and vulnerability to humidity. In addition, AMOLEDs are more expensive than LCDs, so they may not be suitable for everyone's budget.

If you have a project that uses any display or touch technology, US Micro Products can provide a solution designed for your application. Send us an email at sales@usmicroproducts.com.