The indoor LED display from the early three-in-one to the later three-in-one, from the original large spacing to the current small-pitch products, each product upgrade, and LED chip cutting and packaging progress is inseparable. In other words, the upstream chip and package manufacturers have driven the development of LED displays to high density, high definition, and high reliability.
However, after the LED enters the 2mm--3mm interval from the 3mm pitch, the active and passive starts to reverse. Powerful LED display manufacturers have opened up new application modes and application areas for high-density small-pitch displays. Among them, the 2.5mm pitch display is the most typical representative. The LED display began to be applied to a large-area professional display scene, starting and ruling the DLP rear projection technology in the professional display field, and the LCD splicing technology divided the display market. Its speed of sweeping the professional market is amazing. From the sporadic projects of 12 years to the current blooming, the concept of products has been rapidly popularized, and the recognition and confidence of customers have also been greatly improved. This is actually the technical maturity of small-pitch LEDs. The most direct manifestation of the improvement and excellent display application effect progress.
The concept of small-pitch display has been born since 2.5mm. Small-pitch products are mainly concentrated in the range of 1.9--2.0mm, 1.5-1.6mm interval, 1.2mm up and down, and several pixel pitches. The decline in raw material costs and the reduction of defective pixels have enabled the market to have sufficient confidence and budget for the application of higher-definition displays. In the short period of three years from 13 to 15 years, LED small-pitch display applications have basically penetrated into 1.2. Mm pitch and 1.5mm pitch interval.
In addition to the continuous improvement of pixel density and continuous improvement of product stability, the overall design of LED products is also becoming more perfect. In the early stage of small-pitch applications, product design still follows the traditional LED product design ideas, such as non-standard size design, cumbersome assembly, resulting in inconvenient maintenance work. Then, with the market's increasing demand for small-pitch products and the pursuit of customers' product experience, small-pitch products began to look at structural design, display size, and signal source matching to further explore product enhancements. , gradually formed the product system and design style of their respective manufacturers.
Analysis of application areas of small pitch display
As a new generation of indoor professional display panels, small-pitch LEDs have the most direct impact on traditional DLP. In other words, small-pitch LEDs are a technical alternative to DLP in product applications. But this substitution is not a simple one to one. There is still a large application difference between the small-pitch LED display and the DLP, so it is especially important for the technical selection of the screen for different projects. The following is a brief analysis of the professional application scenarios of LED display, which is convenient for eliminating customer misunderstandings in certain product applications.
Radio and TV studio scene application:
The video background application of radio and television broadcasting is the most typical of the anchor background video wall. The technical requirements of the color temperature, brightness, grayscale, viewing angle, contrast and refresh rate of the display panel are quite strict in the studio. Before the emergence of LED HD display, more implementations were back-projection stitching or LCD stitching. Traditional LED displays are difficult to meet the needs of such places in terms of technical parameters and performance, and the emergence of small-pitch products directly subverts the studio's understanding of LEDs. The small-pitch screen can easily meet the application of such scenes in various technical indicators, and the LED display has no small seams and small unit size, which can easily meet the inner curved dance design, and is superior in contrast and color. For other panels, radio and television applications will be an important area for HD LEDs.
For the hot-spotted moiré problem, in the early days of LED application in the field of broadcasting and television, manufacturers and industries tried to circumvent this optical problem by some technical means, but whether it is a soft film structure or a hard curtain structure, it will improve Moore. The grain effect causes the sharpness of the image quality to decrease. For the treatment of the moiré problem, we gradually agree that the moiré effect is minimized by adjusting the camera position and the joint of the camera focal length.
The shooting effect of the curved studio (no moiré treatment)
Combat command and large video conferences:
In large conference venues, multi-person conferences are conducted and judged, and shared video presentations are indispensable hardware facilities. Such scenes have a higher illumination design, or a more transparent lighting design to meet the reading and writing needs of the people present. In this high illumination scene, the display panel is also required to have higher requirements. At the same time, the display panel cannot generate glare, reflection or the like due to the indoor illumination source. At present, most of the small-pitch LED display panels adopt a matte black light, and the display surface is composed of rough pixels, so that the high brightness is satisfied, and the influence of the indoor illumination source is effectively overcome. At the same time, the seamless splicing advantages of LED small pitch have been maximized in this application field. The user experience of the LED display is one level higher than that of the rear projection and the liquid crystal (currently within 2 mm of the narrow side of the liquid crystal).
Military command and command display system
Security monitoring application:
A chemical industry monitoring and display system (liquid crystal + LED screen display program)
In the early stage of small-pitch application, in the design of the security field, especially for small and medium-sized projects, everyone will feel helpless about the lack of resolution of the LED display, because the number of security signals is large, and the number of signals on the upper screen is also large. Under the limited display area, the resolution is insufficient, especially in the case of digital high-definition signal sources, this hardware is not equal. Through the accumulation of many project experiences and familiarity with the security business model, the LED+ LCD mix and match mode is gradually accepted by customers. This mode, under the condition of satisfying the customer's multi-signal screen, introduces the LED as the main screen display, avoids the technical defects such as the seam of the liquid crystal display screen, and can respond well to the security customer in the call judgment signal to enlarge the close-up Demand. Through the flexible configuration scheme, the integration of different dot pitches and display technologies such as liquid crystals, LED display screens have also been cut into the application of security field, and with the increase of dot density, there has been an opportunity to directly discard LCD in some projects. Adopt full screen LED display mode. Of course, with the advancement of LED technology, we will see more new display areas being developed.
Public security monitoring display system (full LED screen display solution)
The characteristics and evolution of the small-pitch display back-end system
With the development of the small-pitch LED display in the past five years, the clarity of the display panel has been greatly improved. As the density increases, the difficulty of further reducing the pixel pitch gradually increases.
Network-based LED display system diagram
At the same time, the background support system of the LED display has undergone profound changes. The signal driving system of the display, also known as the sending card, receiving card. The sending card evolved from the initial PCI slot to the external configuration of the independent power module. It is also available in a small 1 pitch rack using a standard 1U rackmount. These are only changes in the shape and access mode. In terms of the system's load capacity, the transmission card is gradually being adapted to the video resolution of the standard video format, most typically a single access supporting 1080P signals; The introduction of HDMI interface input, etc., is matched with the front-end matrix of the small-pitch signal access platform, the interface and the resolution.
In terms of receiving cards, the capacity of a single card is increased with the increase of the pixel density of the display unit, and the space inside the unit is narrow, and a memory-type receiving card with a strong carrying capacity and a small volume is gradually derived. And in the double backup of the signal, the small-pitch LED display adopts the traditional signal loop form. In the case of stable and reliable system, this form can achieve a certain degree of double backup, but in the near future More manufacturers will replace the signal loop with a dual system card, which will improve the stability of the system.
It can be foreseen that the receiving card supplier of the system is seeking a breakthrough in the business, and also has the form of integrated circuit chip to explore and discuss. It is believed that it will not be too long, and there will be a subversive form in the display driving system.
At the signal access platform level of the video splicing wall, equipment vendors at all levels are gradually being excluded from accepting small-pitch LEDs. From the point of view of the hardware device splicing controller standard on the current splicing wall, the product is output with the fixed resolution of the original interface. In order to adapt to the signal access characteristics of the small-pitch LED products, the interface resolution can be freely defined. Since the original small-pitch manufacturers of LEDs searched for splicers with custom output resolutions, the splicers of the whole industry have already supported or are trying to support LED splicing. This cannot be said to be a compromise and advancement of technology to the market. .
It is not difficult to find that LED small-pitch products are gradually infiltrating into the professional display field from the traditional commercial display carrier, from the product itself to the back-end system, and are constantly adjusted and perfected.
LED comprehensive research and display platform under "Wisdom"
For the LED display system, in the current "wisdom" background, it is the last loop of data flow presentation. However, the technical implementation of data acquisition, transmission link, data storage, decoding and reproduction from the source has been developed to the open interface, unified protocol, and highly compatible direction. It cannot be said that the LED display system has encountered an unprecedented system opening opportunity. In the context of big data, system integration at different stages will be more rapid, LED display system will be more open, and the system's integrity, stability, linkage and handling will be further improved.
Guangzhou Ehang Electronic Co., Ltd. , https://www.ehangmobile.com