1. What is LED?
LED (Light-Emitting Diode) is a highly significant electronic component. It is made of special semiconductor materials such as gallium nitride and emits light when an electric current is applied to the chip. Different materials will emit different colors of light.
LED advantages:
Energy-efficient: Compared with traditional incandescent and fluorescent lights, LED can more effectively convert electrical energy into light, saving electricity.
Long lifespan: The service life of LED can reach 50,000 hours or even longer, without the problems of filament burnout or electrode wear.
Fast response: The response time of LED is extremely short, capable of reacting in milliseconds, which is crucial for displaying dynamic images and signal indication.
Small size and flexibility: LED is very compact and can be easily integrated into various devices and even made into different shapes.
Therefore, LED is widely used in various fields such as home lighting, commercial advertising, stage displays, traffic signs, automotive lighting, electronic products, etc., changing every aspect of our lives and being an important driving force for the development of modern technology.
2. Types Of LED Displays
2.1 LED Display Color Types
Single-Color LED displays: This kind of display shows only one color, such as red, green, or blue. Although it has a lower cost and a simple structure, due to its single display effect, it is rarely used currently and is mainly for understanding. It can still be seen occasionally in some simple information display occasions, such as traffic lights or production status display screens in factory workshops.
Dual-color LED display: It is composed of red and green LEDs. By controlling the brightness and color combination, it can display a variety of colors, for example, yellow (a mixture of red and green). This kind of display is often used in information display scenes with slightly higher color requirements, such as bus stop information display screens, which can distinguish bus lines, stop information, and advertisement content through different colors.
Full-color LED display: It can display various colors formed by the combination of red, green, and blue primary colors and has rich colors and strong expressiveness. It is widely used in places with high requirements for visual effects, such as large outdoor advertisements, stage performance backgrounds, live broadcast screens of sports events, and high-end commercial displays.
2.2 LED Display Pixel Pitch Types
Common pixel pitches: It includes P2.5, P3, P4, etc. The number after P represents the pitch between adjacent pixel points (in millimeters). For example, the pixel pitch of a P2.5 display is 2.5 millimeters. This kind of display is suitable for indoor medium and close viewing, such as in corporate meeting rooms (using P2.5 – P3 displays to show meeting materials) and indoor advertisement spaces in shopping malls (P3 – P4 for playing commodity advertisements).
Fine pitch: Generally, it refers to a display with a pixel pitch between P1.5 – P2. Because the pixel pitch is smaller, the picture clarity is higher. It is mainly used in places with extremely high requirements for picture clarity, such as monitoring and command centers (where staff need to closely observe a large number of monitoring picture details) and TV studio backgrounds (for building large background screens to achieve realistic virtual scenes and special effects display).
Micro pitch: The pixel pitch is P1 or less, representing an ultra-high-definition display technology. It can present extremely fine and realistic images and is used in high-end commercial displays (such as luxury store windows for detailed product display) and scientific research data visualization (displaying complex scientific research data in high-resolution graphics).
2.3 LED Display Usage Types
Indoor LED display: The brightness is relatively low because the indoor ambient light is weak. The pixel pitch is generally small to ensure a clear picture effect when viewed at a relatively close distance. It is mainly used in meeting rooms, exhibition halls, the interior of shopping malls, stage backgrounds (for indoor performances), and other places.
Outdoor LED screen: It requires a higher brightness to resist strong sunlight and complex ambient light. The pixel pitch can vary according to the actual viewing distance and requirements. It is commonly seen in outdoor advertisement spaces, the outer fields of sports stadiums, and transportation hubs (such as outdoor information display screens at airports and railway stations).
2.4 Display Content Types
Text Display
It is mainly used to clearly show text information, with high text clarity and good contrast. Usually, a single-color or dual-color display can meet the requirements, and the refresh rate requirement is relatively low. It is suitable for public transportation guidance, internal information transmission in enterprises, and other scenarios.
Image display
It focuses on presenting images with high resolution and accurate color. It can display both static and dynamic images well. It needs to balance brightness and contrast and has strong color performance. It is often used in commercial displays and art exhibitions.
Video display
The key is to be able to play videos smoothly, with a high refresh rate, high color reproduction, and the ability to optimize the dynamic range and contrast. The pixel pitch is well matched with the viewing distance. It is applied in advertising media, stage performances, and event backgrounds.
Digital display
It displays numbers in a clear and prominent way, with flexible number formats, large font sizes, and high brightness. The requirements for color and refresh rate are limited, and usually, a single-color or dual-color display is sufficient. It is used for timing and scoring in sports events, information release in financial institutions, and other scenarios.
3. Types of LED Technology
Direct-lit LED: In this technology, LED beads are evenly distributed behind the liquid crystal panel, and the light is evenly distributed to the entire screen through a light guide plate. This way can provide better brightness uniformity, show more vivid colors and higher contrast, and is widely used in mid-to-high-end liquid crystal monitors and televisions. However, due to the need for more beads, the module is thicker, which may affect the thinness of the screen, and the power consumption is relatively high.
Edge-lit LED: This technology installs LED beads on the edge of the screen and uses a special light guide structure to transmit light to the entire display surface. Its advantage is that it can achieve a thinner design, meet the market demand for a thin and light appearance, and has lower power consumption. However, because the light source is located at the edge of the screen, it may lead to an incomplete uniform distribution of screen brightness. Especially in terms of contrast and color performance, it is slightly inferior to direct-lit LED. In some cases, light leakage may occur in black pictures.
Full-array LED: Full-array LED is an upgraded version of direct-lit LED. By dividing the beads into zones and independently controlling the brightness, it achieves more precise local dimming. This technology provides higher contrast and color performance. Especially when presenting HDR content, it can better restore the details of highlights and shadows and enhance the visual experience. Due to its complex circuit design and the need for more beads to achieve local dimming, the cost is higher, and it has higher requirements for driving chips and control systems.
OLED: OLED is a self-luminous display technology, and each pixel can emit light independently without a backlight. Its advantages include high contrast, deep black, vivid colors, a wide color gamut, and a fast response time, which is suitable for displaying dynamic pictures. OLED screens can also be made extremely thin and have flexibility, which is suitable for foldable devices. However, the production cost of OLED technology is high, and its brightness performance in strong light environments is not as good as other technologies.
QLED: QLED is based on LED backlight technology and combines quantum dot materials, which can provide a wider color gamut and more accurate color performance. QLED inherits the advantages of LED backlight, such as high brightness, long life, and low energy consumption. At the same time, the production cost is more economical than OLED, with a high cost-performance ratio. Nevertheless, QLED still depends on a backlight, and its contrast and black performance are slightly worse than OLED.
Mini LED: Mini LED is an emerging technology. By shrinking LED beads to the micron level and using a direct-lit backlight layout, it significantly improves contrast and brightness uniformity and presents a better picture effect. Mini LED not only inherits the advantages of traditional LED but also can provide higher resolution and image details. Compared with OLED, it has a longer lifespan and is less prone to burn-in, and the cost is relatively lower.
Micro LED: Micro LED further shrinks LED chips to the micron or even nanometer level and directly transfers them to the display panel to emit light as independent pixels, possessing the advantages of self-luminous technology, providing high contrast, accurate colors, excellent brightness, and a fast response time. Micro LED technology can be made very thin, has low power consumption, and a long service life. Although its production cost is high and the technical difficulty is large, it has broad market potential.
Post time: Dec-05-2024