In the development process of the flat panel industry, the new technology of the splicing wall is constantly being updated, which has set off a new pattern of the large screen splicing industry. DLP mainstream splicing technology has experienced many years of market test. Although it has many advantages such as high resolution, large size and small seams, the market share is rapidly declining in the face of PDP splicing and the impact of new liquid crystal splicing technology. The LCD splicing wall is recognized by more and more users for its high-quality display effect, low energy consumption, long service life and low maintenance cost. It is widely used in security, surveillance, medical, radio and television, advertising media and Other fields. application. DLP stitching (DLP rear projection splicing system) DLP is the abbreviation of “Digital Light Processionâ€, which means digital light processing, which means that this technology first digitally processes the image signal and then projects the light. The technology of visual digital information display is completed by DMD (Digital Micromirror Device). To be specific, DLP projection technology uses digital micromirror wafers (DMDs) as the primary key processing component to implement digital optical processing. The principle is to pass the cold light source emitted by the UHP bulb through the condensing lens, homogenize the light through the Rod, and the processed light passes through a Color Wheel to divide the light into RGB three colors (or RGBW and other colors). ), the color is projected by the lens on the DMD chip, and finally the reflection is imaged on the projection screen through the projection lens. DLP large-screen splicing system is based on DLP projector and equipped with image processor, high brightness, high resolution, vivid color video wall, can display various computers (workstation), network signals and various video signals, screen Can roam freely, open windows, zoom in and out and overlay. DLP splicing wall is made up of multiple rear projection display units. Its main feature is the large size of the screen. The current mainstream size on the market is 50 inches, 60 inches, 67 inches, with the user's demand for large screen size. The improvement, 80-inch, 84-inch, 100-inch, 120-inch is also gradually used. The resolution of the DLP splicing wall is superimposed by the resolution of each display unit, and an ultra-high resolution can be obtained. Such as: the single is 1024 * 768 3 * 2 splicing wall, the resolution of the entire wall after splicing is as high as 1024 * 3, 768 * 2. In addition to the large size, another major feature of the DLP splicing wall is that the seam is small. Although there are screen seams between the display units, the physical seam between the unit cabinets has been controlled within 0.5mm. . However, there are still some fatal shortcomings in the DLP rear projection splicing system. Since the DLP display uses multiple display unit splicing, the color and brightness are uneven when a certain number of splicing is achieved, and the power consumption is large, and the internal illuminating bulb is continuously working. After 6000-8000 hours, there will be a decrease in brightness. In order to maintain a good display effect, the lamp needs to be replaced later in the project application, so the maintenance cost is very large. In addition, due to the large thickness of the DLP splicing unit, there is still enough space left on the back, which is also a problem for some environments with relatively small spaces. PDP stitching (plasma stitching) PDP (Plasma Display Panel, plasma display panel in Taiwan) is a display technology that uses gas discharge, and its working principle is very similar to that of fluorescent lamps. It uses a plasma tube as a light-emitting element. Each plasma tube on the screen corresponds to one pixel. The screen uses glass as a substrate. The substrates are separated by a certain distance, and the surrounding is sealed by airtightness to form a discharge space. The discharge space is filled with a mixed inert gas such as helium or neon as a working medium. A metal oxide conductive film is coated on the inner side surfaces of the two glass substrates as an excitation electrode. When a voltage is applied to the electrodes, a plasma discharge phenomenon occurs in the mixed gas in the discharge space. The gas plasma discharge generates ultraviolet light, the ultraviolet light excites the fluorescent screen, and the fluorescent screen emits visible light to reveal an image. When a fluorescent screen coated with phosphors of three primary colors (also called three primary colors) is used, the ultraviolet light excites the fluorescent screen, and the light emitted by the fluorescent screen is red, green and blue. When each primary color unit realizes 256-level gray scale and then performs color mixing, color display is realized. Plasma display technology can be divided into two types: DC-type PDP with electrodes in direct contact with gas and AC-type PDP with electrodes covering the dielectric layer. At present, there are mainly three types of color PDPs researched and developed: single-substrate (also known as surface discharge) AC PDP, dual-substrate (also known as counter-discharge) AC PDP and pulse storage DC PDP. From the technical principle, since the plasma tube that emits light in the PDP screen is evenly distributed in the plane, the center and the edge of the displayed image are completely identical, and no distortion occurs, realizing a pure plane in the true sense. Because there is no electron beam motion in the display process, there is no need to resort to electromagnetic fields, so the external electromagnetic field will not interfere with it, and it has better environmental adaptability. It is believed that this is also the long-term use of military equipment by the US military. important reason. Since the PDP illumination does not require a background light source, there is no viewing angle and brightness uniformity of the LCD display, and higher brightness and contrast are achieved. The design of the same plasma tube for the three primary colors also avoids focus and convergence problems, enabling very clear images. Compared with LCD display technology, the larger the screen of the PDP, the higher the depth of field and fidelity of the image. In addition to the advantages of brightness, contrast and viewing angle, PDP technology also avoids the response time problem in LCD technology, which is a crucial factor in dynamic video display. Therefore, from the current technical level, the advantages of PDP display technology in the field of dynamic video display are more obvious, and it is more suitable for use as a television or home theater display terminal, especially the display of a large screen is more suitable for an upcoming HDTV. The PDP display has no scan line scan, and the pixels are completely imaged by the pixels, so the image is clear and stable without flicker, and does not cause eye strain. The PDP also has no X-ray radiation. Due to these two characteristics, the PDP is a true green display product. At present, most of the plasma panels used for splicing are provided by South Korea's Orion, and the 42-inch M-PDP plasma panel produced by Orion is produced by Olympian's exclusive DZF (Dead-ZoneFree) process, which successfully removes 3-4cm wide around the ordinary plasma panel. The edge of the glass, the so-called "display dead zone", is clearly displayed at every pixel on the edge of the screen. After splicing, the gap between the display units is less than 3mm, achieving the best plasma splicing effect, and the curtain wall picture is perfect. The plasma display body is ultra-thin, small in size, suitable for wall mounting, so it is suitable for installation in any area. Even if your space is very small, it is quite possible to install a plasma display. In terms of installation space, it is more than DLP. Save a lot. However, plasma screen products have large pixel gaps, low reliability compared to other products, high power consumption, and inherently insufficient lifetime. After 5000-10000 hours, the screen brightness will be reduced by half, and it is difficult to reach an altitude of 2500 meters or more. Normal work, its most fatal weakness is that it is easy to burn when displaying computer images or still images for a long time. The so-called burning phenomenon means that the plasma inside the screen changes when the plasma TV is in the image at rest for a long time, which is not working properly. It is shown that there is an image afterimage at a specific position on the screen, and it cannot be removed regardless of any source. LCD splicing (LCD splicing) The LCD liquid crystal display is the abbreviation of Liquid Crystal Display. The LCD is constructed by placing liquid crystals in two parallel glass. There are many vertical and horizontal small wires between the two glass, and the rod crystal molecules are controlled by energization or not. Change direction and refract light to produce a picture. The LCD consists of two glass plates, approximately 1 mm thick, separated by a uniform spacing of 5 μm containing liquid crystal material. Since the liquid crystal material itself does not emit light, a light pipe as a light source is provided on both sides of the display screen, and a backlight plate (or a light homogenizing plate) and a reflective film are formed on the back of the liquid crystal display, and the backlight plate is composed of a fluorescent substance. Light can be emitted, the main function of which is to provide a uniform background light source. The light emitted by the backlight enters the liquid crystal layer containing thousands of liquid crystal droplets after passing through the first polarizing filter layer. The droplets in the liquid crystal layer are all contained in a small cell structure, and one or more cells constitute one pixel on the screen. Between the glass plate and the liquid crystal material is a transparent electrode, the electrode is divided into rows and columns, at the intersection of the rows and columns, by changing the voltage to change the optical rotation state of the liquid crystal, the liquid crystal material acts like a small light valve. Around the liquid crystal material are a control circuit portion and a drive circuit portion. When the electrodes in the LCD generate an electric field, the liquid crystal molecules are distorted, and the light passing through them is regularly refracted, and then filtered through the second layer of the filter layer to be displayed on the screen. LCD splicing (liquid crystal splicing) is a new splicing technology that has emerged in recent years after DLP splicing and PDP splicing. LCD LCD splicing walls have low power consumption, light weight and long life (usually 50,000 hours of normal operation) , no radiation, uniform brightness of the screen, etc., but its biggest drawback is that it can not be seamlessly spliced, it is a bit regrettable for industry users who require very fine display screens. Since the LCD screen will have a frame when it leaves the factory, the frame (seam) will appear when the LCD is spliced ​​together. For example, the border of a single 21-inch LCD screen is generally 6-10mm, and the seams of the two LCD screens are 12- 20mm. In order to reduce the gap of liquid crystal splicing, there are several methods in the industry, one is narrow seam splicing, the other is micro splicing splicing, micro splicing is the shell of the LCD screen that the manufacturer will buy back, and the glass and glass Intersexual splicing, but this approach is more risky. If the LCD screen is not properly removed, it will damage the quality of the entire LCD screen. At present, there are very few manufacturers in China that use this method. In addition, after 2005, Samsung introduced a dedicated LCD screen for splicing - DID LCD screen. The DID LCD screen is designed for splicing, and its frame is made very small at the factory. At present, the most common liquid crystal size of LCD liquid crystal splicing wall is 19 inch, 20 inch, 40 inch, 46 inch. It can be spliced ​​according to customer's needs, up to 10X10 splicing, backlight illumination, and long life of 50,000 hours. Secondly, the dot pitch of the liquid crystal is small, and the physical resolution can easily reach the high definition standard. In addition, the liquid crystal panel consumes less power and has a lower heat generation. The liquid crystal screen of 40 inches or more has a power of about 150 W, which is only about 1/4 of the plasma. And the operation is stable and the maintenance cost is low. At present, the products suitable for LCD splicing include Samsung DID LCD screen, NEC ultra-narrow LCD screen, and Vewell ultra-narrow LCD screen. Although they are all LCD splicing products, Samsung's ultra-narrow LCD screen has a high cost performance. Ideal for large screen splicing projects in the surveillance field. Kenwood Portable Radio,Kenwood Vhf Handheld Radio,Kenwood Dual Band Portable Radio,Kenwood Vhf Portable Radio Guangzhou Etmy Technology Co., Ltd. , https://www.digitaltalkie.com