Characteristics and identification methods of full-color LED display

Full color LED display screen is a kind of LED display screen, which has the following characteristics:

(1) Rich colors: it is composed of three primary colors (red, green and blue) display unit boards, and 16777216 colors are composed of 256 gray levels of red, green and blue, so that the electronic screen can display dynamic images with rich colors, high saturation, high resolution and high display frequency;

(2) Good effect: using nonlinear correction technology, the image is clearer and the sense of hierarchy is stronger;

(3) Strong reliability: distributed scanning technology and modular design technology are adopted, with higher reliability and stability;

(4) Super detection function: real-time detection of whether the pixels in the screen are invalid and remote transmission of the working state of the pixels;

(5) The new mask design makes the light emitted by the LED almost 0 reflect to ensure the display effect of the screen;

(6) High flatness: the flatness coefficient of the box is less than 0.5mm, and the power factor is more than 88%;

(7) Diversified input signals: support RF, s-vidieo, rgbtv, Yut, YC, composition and other stage signals;

(8) High waterproof performance: waterproof rubber ring is used on the back of the module, and high-quality imported glue is used for glue filling on the front;

(9) Durability: high temperature spraying technology is adopted to greatly improve the anti rust function; The light-emitting module is guaranteed for ten years, the mask is non reflective, UV resistant, and does not fade for five years;

2、 Selection of supporting products and materials for full-color LED display

1. LED lights and chips.

LED lamp is not only LED light-emitting tube, but also the key device of LED electronic display screen. Therefore, LED products with reliable quality and mature packaging should be adopted. The selected LED products must have the requirements of good stability, small dispersion, HBM greater than 4000V, small attenuation amplitude, strong pressure resistance, brightness, wavelength, high angle consistency, good light distribution effect, and resistance to temperature difference, humidity and ultraviolet rays.

2. Box.

The whole is made of steel plate or aluminum, and the door opening structure is adopted. The top of the box adopts pins and the bottom adopts guide sleeves to ensure accurate positioning between the boxes. The overall protection of the box shall meet the IP65 standard. In addition, the heat dissipation shall be fully considered in the structure.

3. Switching power supply.

The power supply of the display screen adopts the well-known brand switching regulated power supply module that has passed the certification. All switching power supplies have been strictly tested, screened and aged. Ensure full compliance with international safety and quality certification requirements to meet the requirements of long-term stable and reliable operation of the display screen. Under rated operating conditions. Ensure that the service life is greater than 10 years.

4. Connector.

Connector is an important connecting device in the system. High quality connector products shall be adopted to ensure the thickness of pure gold coating of the connector and maintain the best electrical connection performance. Ensure the good electrical connection performance of the system in high temperature and high humidity environment, which can make the system operate stably and reliably for a long time.

5. Circuit board.

The circuit board adopts flame-retardant epoxy plate, with reasonable design layout and standardized wiring, which meets the requirements of electromagnetic compatibility and circuit stability. The processing manufacturer shall select the products produced by well-known manufacturers.

6. Drive chip IC device.

The driving circuit adopts the constant current driving chip of international famous brand. In a large temperature range, maintaining high-precision constant current output and high reliability can significantly improve the uniformity and reliability of the display screen. The main materials of the display system shall pass CE, FCC, UL, CCC, ISO9000 and other certifications. I believe that if we do the above and adhere to reliable supporting facilities and materials and professional R & D and design technology, we will be able to reduce the failure rate of the display screen and greatly improve the reliability and stability of the LED display screen.

3、 Identification of full color LED display

The quality of full-color LED display can be judged from the following aspects:

1. Flatness.

The surface flatness of LED display screen shall be within ± 1mm to ensure that the displayed image is not distorted. Local bulges or recesses will lead to dead corners in the visual angle of the display screen. The flatness is mainly determined by the production process.

2. Brightness and visual angle.

The brightness of the indoor full-color screen should be more than 800cd / m2, and the brightness of the outdoor full-color screen should be more than 1500cd / m2 to ensure the normal operation of the display screen, otherwise the displayed image will not be seen clearly because the brightness is too low. The brightness is mainly determined by the quality of LED beads. The size of the visual angle directly determines the audience of the LED display screen, so the larger the better. The size of the visual angle is mainly determined by the packaging mode of the die.

3. White balance effect.

White balance effect is one of the most important indicators of LED display. In terms of chromatics, pure white will be displayed only when the ratio of red, green and blue primary colors is 1:4.6:0.16. If there is a deviation in the actual ratio, there will be a deviation in the white balance. Generally, we should pay attention to whether white is blue or yellow green. The quality of white balance is mainly determined by the control system of LED display screen, and the lamp beads also have an impact on the restoration of color.

4. Color reduction.

Color reducibility refers to the color reducibility of LED display screen, that is, the color displayed by LED display screen should be highly consistent with the color of playback source, so as to ensure the authenticity of image.

5. Product design.

There are many kinds of full-color LED displays, including indoor and outdoor energy-saving, bright, high refresh and portable products. All walks of life have different requirements for LED displays. Therefore, when buyers distinguish the quality of LED displays and select LED displays, they should gather their own needs and whether the manufacturer's LED display products can meet their own needs to the greatest extent.

6. Material control.

The selection of materials plays a decisive role in the quality of LED display. Select high-quality raw materials to control the quality of LED display at the source. Therefore, for buyers, it is the focus of investigation.

1) The high-grade LED lamp represents Riya Kerui (chip packaging) mid-range wafer Guanglei Shilan (chip). LED lamp involves the LED upper and middle industrial chain, especially the domestic packaging industry. Similarly, the LED quality made by wafer Shilan chip is uneven due to different packaging manufacturers. The representative of LED lamp packaging tube of medium and high products is Yiguang (Taiwan) Guoxing Lehman.

2) LED Driver IC: as the leading manufacturer of global LED driver, Jiji technology has ranked the first in the world in the field of LED display driver for many years, and has achieved a market share of more than 60% in China and more than 50% in the world. Ji5024 is the most choice of medium and high-end LED display products.

3) Power supply base (reinforced): the power supply base is the main device to connect the power line with the PCB board. Although it is not the main aspect to determine the quality of LED display screen, its firmness, durability and conductivity also affect the service life and protection grade of display screen.

4) Needle arrangement (with simple ox horn): the needle arrangement is the main component connecting the control system and the PCB control circuit through the wire arrangement. The needle arrangement with ox horn is preferred, which can not only prevent the rework caused by the reverse insertion of the wire arrangement during screen installation, but also effectively prevent the exposed needle from damaging the screen installation and maintenance personnel.

5) Resistance, capacitance and other components: as the saying goes, there is no big or small matter. Because the LED display screen is often switched on and off, the quality of capacitance also affects the protection of the display screen body when switching on and off. Resistance is the main component to control the current of the display screen, and large brand products are preferred.

6) LED module mask and bottom shell: mainly made of plastic. Imported high-quality materials, anti deformation, strong environmental resistance.