OLED display screen (Organic Light Emitting Diode) is a display technology based on the self emission of organic materials. Its core feature is that each pixel can independently emit light without the backlight module required by traditional LCD (liquid crystal display), thus it has the advantages of ultra-thin, high contrast, flexible and bendable, and is widely used in fields such as mobile phones, televisions, wearable devices, etc.
1、 The basic structure and principle of OLED
Structural composition
Organic material layer: including hole transport layer (HTL), emissive layer (EML), and electron transport layer (ETL).
Electrode:
Anode (usually indium tin oxide, ITO): Injects holes (positive charges).
Cathode (metal material such as aluminum): Injects electrons (negative charge).
Substrate: Glass or flexible material (such as polyimide) that supports the entire structure.
Luminous principle
After being powered on, electrons and holes combine in the luminescent layer, releasing energy and exciting the organic material to emit light.
Different organic materials can emit the three primary colors of red (R), green (G), and blue (B), which can be combined to achieve full-color display.
2、 The core advantages of OLED
High contrast and pure black display
Pixel independent control, when turned off, can achieve pure black (with almost infinite contrast) and brighter colors.
Ultra thin and flexible design
No backlight layer required, thickness can be less than 1mm; flexible substrate supports curved screens and foldable screens (such as Samsung Galaxy Fold).
Fast response speed
Microsecond response time, far exceeding LCD (millisecond level), suitable for dynamic graphics (such as games, high-speed videos).
Wide viewing angle and low power consumption
The viewing angle can reach over 170 ° without color shift; When displayed in black, the pixels are turned off, significantly reducing power consumption.
Process simplification
The manufacturing steps are fewer than LCD, and it supports mass production of printing technology (such as inkjet printing OLED).
3、 Limitations of OLED
Life expectancy issue
Organic materials are prone to aging, especially blue pixels with a short lifespan (about 15000 hours), which may cause screen burn-in (residual image).
High cost
Large sized OLEDs (such as televisions) have low yield and are significantly more expensive than LCDs.
Brightness limit
Long term high brightness operation will accelerate aging, and the peak brightness is usually lower than the Mini LED backlight solution.
4、 The main types of OLED
By driving mode
PMOLED (Passive Matrix OLED): Simple structure, low cost, but only suitable for small screens (such as smartwatches).
AMOLED (Active Matrix OLED): Each pixel is independently controlled by TFT (Thin Film Transistor), supporting high resolution and large size (mainstream phones, TVs).
According to the screen shape
Rigid OLED: glass substrate, traditional form.
Flexible OLED: bendable and foldable, used for folding mobile phones (such as Huawei Mate X).
Transparent OLED: Partially pixel transparent, suitable for window display or AR devices.
5、 Application scenarios
Consumer Electronics
Smartphones (such as Super Retina XDR on iPhone 14 Pro), smartwatches (Apple Watch).
TV and monitor
LG's WRGB OLED TV and Samsung QDOLED (quantum dot enhanced).
Cars and Wearables
In car central control screen, VR headset (such as Meta Quest Pro).
Emerging fields
Transparent advertising screen, rollable TV (such as LG Signature OLED R).
6、 OLED vs other display technologies
|Features | OLED | LCD | Micro LED|
|Backlight Requirement | No Backlight Required | Backlight Required | No Backlight Required|
|Contrast | Near infinity | Approximately 1000:1 | Near infinity|
|Thickness | Ultra thin (<1mm) | Thicker (including backlight) | Medium|
|Lifetime | Short (especially blue pixels) | Long | Extremely long (inorganic materials)|
|Cost | High (Large Size) | Low | Extremely High (Not mass-produced)|
7、 Future Development Trends
Material Innovation
Develop blue phosphorescent materials with longer lifespan to enhance the overall screen lifespan.
Printing OLED
Inkjet printing technology reduces production costs and promotes the popularization of large-sized OLEDs.
Folding and Curling Screen
Optimize hinge design and flexible substrate to enhance durability (such as OPPO Find N2).
Transparency and miniaturization
Transparent OLED is used for AR glasses, while Micro OLED (silicon-based OLED) is suitable for VR ultra-high resolution requirements.
If you need to further understand the manufacturing process or specific product models of OLED (such as Samsung E6 screen, BOE flexible OLED), you can provide more detailed directions!
