The LED display has been developed for 20 years by 2017, and the indoor LED display has also taken a step into the high-end conference room LED display. For the conference room LED display, the intuitive experience and the results achieved are Unmatched by other traditional projectors. What are the model sizes of the indoor meeting room LED display? What is the price of conference LED display? This is a question that is more concerned by friends who are interested in needs.

Like other display devices, LED electronic displays have been accompanied by technological progress and upgrades since their birth. Compared with the large size, ultra-thin, and high resolution of other display devices, LED displays have a granular image when viewed at close range. , Long-term viewing comfort and other technical aspects have also been greatly improved; and with the rapid breakthrough of small-pitch, high-density, low-brightness displays, and other technologies, LED displays have been introduced indoors, and DLP splicing, LCD splicing, PDP splicing , Engineering projectors, etc. have become the mainstream indoor large-scale display methods, and are more and more widely used in indoor multifunctional auditoriums, conference centers and dispatching command centers. The latest quotations and model sizes of LED displays in conference rooms are as follows

According to actual needs and status symbols, conference room LED displays are basically the small-pitch LED display models currently selected. The models and sizes of different LED display manufacturers in the industry are different. The following is Winbond Optoelectronics Model and size of led display in conference room.
LED display model and pixel density of conference room:
       

P1.667 Pixel pitch: 1.667mm Pixel density: 359856㎡

        P1.923 Pixel pitch: 1.923mm Pixel density: 270422㎡

        P1.875 Pixel pitch: 1.875mm Pixel density: 284444㎡

        P1.56 Pixel pitch: 1.56mm Pixel density: 409600㎡

        P1.47 Pixel pitch: 1.47mm Pixel density: 472593㎡

        P1.25 pixel pitch: 1.25mm pixel density: 640000㎡

Conference room LED display module size:

        P1.667 module size: 150mm x 150mm

        P1.923 module size: 150mm x 150mm

        P1.875 module size: 240mm x 140mm

        P1.56 module size: 200mm x 100mm

        P1.47 module size: 150mm x 150mm

        P1.25 module size: 150mm x 150mm

The price of LED display in conference room is affected by the following factors:

　　 1. Quotation for the screen body: that is, the quotation of the conference room display screen is ××yuan/square meter, and the selected materials are different, and the price is also different. (Including the cost of LED die, IC driver chip, power supply and LED box.)

　　 2. Control system cost: That is to control the number of computers and receiving cards and sending cards, the number needs to be determined according to the size of the LED screen in the conference room, and then the cost is calculated.

　　 3. Auxiliary equipment costs: distribution cabinets, computers, audio amplifiers, air conditioners, control cards, lightning arresters, LED video processors, etc. It can be selected according to requirements, and customers can purchase by themselves.

　　 4. Display playback software: including computer system software, as well as LED video playback software, etc., generally free.

　　 5. Steel frame structure cost: including manual installation costs. Generally, the steel frame column structure is more expensive than the wall installation structure. You can also ask the LED display manufacturer to provide the steel frame structure design drawings, and the customer can find the local manufacturer to make it.

　　6. Transportation cost: The cost incurred by logistics transportation is paid by the customer.

　　7. Installation cost: When the goods arrive at the scene, the technical engineer of the LED display manufacturer will come to assist in the installation and debugging. There is no charge for installation, but the general board and lodging expenses and round-trip travel expenses of the technical engineer are required.

        The conference room LED display quotation and model size are probably the above information. Winbond has had a number of successful cases of conference room LED display. The specific price requires both parties to comprehensively determine the actual size of the project, installation environment, and display requirements. Given a reasonable solution, I believe Winbond Ying Optoelectronics can give you a satisfactory tour of the meeting room led display.

This article combines the more comprehensive design, installation, testing and maintenance of the LED display in the conference room. This is also the relevant information that users need to know.

Basic situation of the project

1.1 Construction requirements of the project

The display system of the multifunctional auditorium is divided into three parts: the main display (hereinafter referred to as the "main screen"), the auxiliary display (hereinafter referred to as the "auxiliary screen") and the monogram screen. The main screen construction requirement is to build a large-format, high-definition large screen, display multiple computer digital signals, local video cameras, remote monitoring or remote conference video signals, etc., to achieve the display of pictures, explanation materials, video conferences, etc. At the same time, the background of the stage performance should be taken into consideration; the auxiliary screen construction needs to display a standard-definition signal to realize the display of the auxiliary content of the meeting, and can also be used as a report and subtitles during the performance; the monogram screen needs to display text in multiple colors.

The stage of the auditorium is 20m wide, 17m deep, and 18m high. The platform entrance is 15m wide and 7.8m high; lighting, curtains and other stage machinery are installed above the stage; the ear walls on both sides of the platform are 3m from the ground, 8m wide and 6m high. The design of the main screen has a display area of at least 72m2 (12m×6m). The front of the screen is the venue for conferences and performances on the podium, and behind the screen is the space for actors to pass and maintain. The first row of audiences are at least 17m away from the screen; the auxiliary screen is on the ear wall, displaying The area is at least 12m2 (4m×3m).

1.2 Determination of display technology

Regarding the DLP splicing display wall, LCD splicing display wall and LED electronic screen, no matter what method is used, it must meet the display requirements of auditorium video conferences and live performances. Based on the scene situation, the three display methods are analyzed and compared.

1) DLP splicing display wall

The advantages of the DLP splicing system are high contrast, fine colors, high resolution, and the seam is less than 0.25mm; the disadvantage is that the display effect is greatly affected by the stage lighting, and the brightness and color will be difficult to be uniform due to the attenuation of the projection equipment. The lamp life Short, high maintenance cost.

2) LCD splicing display wall

The LCD splicing unit size is generally 1397mm, 1524mm, the unit brightness is less than 1000cd/m2, the minimum seam is 2.4mm, and the life is 60,000 hours. The advantages are light and thin body, low noise, low heat dissipation, easy maintenance, suitable for close viewing; disadvantages Because of the small unit size, there are many and obvious seams after splicing large screens.

3) LED display in meeting room

The indoor conference room LED display has a brightness greater than 1200cd/m2 and can be spliced into a seamless display wall in any area. The color consistency is good, the life span is 100,000 hours, and the application environment is low; the disadvantage is that the particles are obvious when viewed at close range. The area is not large enough, and the image needs to be compressed, which affects the clarity of the screen display.

Compared with the three display technologies, for the DLP method, in order to clearly view the screen display content at a distance of 17m, it is required to use high-brightness, high-contrast laser light source DLP projection for multi-screen splicing. The project cost is high, and performance applications are possible. Will produce dust and props touch, so DLP splicing display wall is not an ideal choice;

For the LCD mode, the display of the video conference image will show the bad display effect of human face segmentation. At the same time, the screen brightness is not high enough for the auditorium environment at a distance of 17m;

For the LED display method, since the minimum viewing distance is 17m and the display area is about 72 m2, the shortcomings of LED splicing walls are completely negligible, and as the cost of electronic products decreases, the overall cost is not high, and the system has a long life and low Application environment, easy to maintain, suitable for conference TV and stage performances.

Key technologies affecting the quality of display screens

When designing the conference room LED display screen, three important factors should be considered: the need for display content, the space conditions of the venue, the size of the display unit module or the pixel size, and at the same time ensure that the production process and technical indicators are suitable for indoor practical applications. Demand, combined with the cost of the entire project, make a reasonable design.

2.1 Selection of display dot pitch

The visual granularity mainly comes from the human eye’s ability to distinguish. When viewing two points at a certain distance, when the two points are close to a certain extent, the human eye will not be able to distinguish. With the improvement of LED display manufacturing technology in the past two years, the resolution of small-pitch LED screens has continued to increase, and the indoor display design has been upgraded from the initial selection of the smallest dot pitch specification scheme to the selection of the appropriate dot pitch specification scheme. Generally, the minimum viewing distance, the best viewing distance, system cost and screen display resolution are comprehensively compared to determine the display screen specifications used by the system.

Table 1 compares the typical display specifications. The specifications of P5, P4, P3, P2.5, P2, P1.6 are commonly used indoor specifications, "P4" means that the pixel pitch is 4mm, and the minimum viewing distance is distinguished by the human eye. The distance between the pixel and the particle is not known, but this distance will damage the eyesight when viewed for a long time. The best viewing distance is the comfortable distance for viewing the screen, which is also the clearest distance.

From the comparison of Table 1, it can be seen that the minimum viewing distance and the best viewing distance of the three specifications of P2.5, P2 and P1.6 are very close to the viewing requirements of large flat-screen TVs. The resolution of the whole screen is as high as 4800×2400. The screen can display a clearer picture, but a high-definition signal on a 12m wide screen needs to be magnified by 3 to 4 times, and two high-definition pictures need to be magnified by 2 times; at the same time, high-resolution display requires high-performance image processing equipment , The overall cost of the system will be high.

The P5 and P4 specifications cannot display two high-definition pictures at the same time on a 12m wide screen, and cannot meet the display requirements of high-definition conference TV pictures. The two specifications of P3.1 and P3 can meet the requirement of displaying two high-definition pictures at the same time. According to the size of the display screen, P3.1, which is more cost-effective, is finally selected as the display point distance of the main screen and auxiliary screen of the project, and P4 is selected as the display point distance of the monogram screen; the LED wick is selected from domestic first-line brands, such as Silan and Jing Yuan, Ganzhao, San'an, etc.

2.2 Pixel packaging technology

One factor that determines the quality of LEDs is the main materials, such as chips, brackets, glue (epoxy resin), gold wires, etc. The other factor is the packaging process. Pixel packaging technology is related to the color saturation, viewing angle and other display effects of the entire display screen, production cost, quality stability, etc., and it is one of the most critical indicators for selecting an LED display.

The mainstream LED indoor packaging technology mainly includes surface mount and in-line modes

Surface mounting refers to pasting the packaged light-emitting tube on the circuit board, and then processing the integrated circuit welding process into the screen. It has good heat dissipation, uniform color, and the entire display screen can be maintained from the front, which greatly reduces the maintenance cost and difficulty. At the same time, the metal compound is filled in the packaging process, which has good color mixing effect and soft light, which is more suitable for indoor applications.

The direct plug-in module is to encapsulate the light-emitting tube into a rectangular shape, and then put the red, green and blue tubes together to form a pixel module, which is directly installed on the PCB board for welding. The process is relatively simple, the cost is low, and the defective pixel rate is high. , Mainly used in outdoor displays.

The pixel structure of the indoor screen has two methods: three-in-one surface mount and three-in-one surface mount (separate surface mount).

Three-in-one surface mount means that the red, green and blue light-emitting points are packaged and combined in the same light-emitting tube. It is a point when viewed close up, and when enlarged, it is a line of separation of the three light-emitting points, which requires high materials and processes in the production process. Mainly used in the production of small-pitch, high-density high-end LED displays.

Three-in-one surface mount (separate surface mount) means that the red, green, and blue light-emitting points are separately packaged, and arranged into 1 pixel after packaging, and then packaged with a mask for protection against dust, scratches, and protection Luminous wafers. The three-in-one is to separate the surface mount, the three-point power supply is separated, the power consumption is small, and the single lamp can be repaired, and the cost is low.

Generally speaking, in order to improve the display effect of the LED display in the conference room, use surface mount three-in-one, black light technology, and gold wire packaging

2.3 Design of LED control circuit

The LED control part is the core part that determines the display effect, and the control circuit has a built-in high-performance single-chip micro-control chip. The controller sends control signals and data to the LED driver chip through an internal control program. After the LED driver chip receives the signal, it generates corresponding actions, thereby achieving individual control of each red, green, and blue LED light-emitting chip.

2.3.1 Drive system

The function of the LED driving part is to receive color data and drive the LED display to display according to the brightness value indicated by the data. There are usually three modes of constant current, voltage stabilization, and constant voltage-constant current.

The output current of the constant current drive circuit is constant, and the output DC voltage changes with the change of the load resistance. The whole circuit is not afraid of the load short-circuit, but it is strictly forbidden to open the load completely. The voltage stabilizing circuit outputs a fixed voltage, and the output current changes with the increase or decrease of the load. The whole circuit is not afraid of the load being open, but it is strictly forbidden to short the load completely. Constant voltage first and then constant current is the most ideal driving circuit. It not only needs to detect the LED current, but also control the LED voltage, which helps to improve the life of the LED and reduce the power consumption. It is generally used in high-end LED products.

2.3.2 Control system

The display effect of the LED depends on the size and time of the current and voltage passing through it, so the control system mainly controls the power output of the LED. At present, the LED power supply designed by PWM (pulse modulation) control method has a conversion efficiency of 80% to 90%, and the output voltage or current is very stable, which is a highly reliable power supply.

PWM can control the time ratio of LED on and off. By dividing the time ratio into several levels, the LED can display a corresponding number of gray levels (gray scales). The product of the gray levels of the three primary colors is the number of colors that can be reproduced in theory on the display screen, generally 256 levels, and the number of colors reaches 16.7M, which can display 24-bit true color information.

Generally, the frequency of PWM is greater than 100Hz, otherwise there will be flickering and scanning lines when viewing. Nowadays, large screens with 10-bit gray scale have a refresh rate of 800 to 1000 Hz. The highest refresh rate in the LED industry is 6800 Hz. Under the normal viewfinder and rotation of the camera, the LED screen display is stable and flicker-free, and the gray scale is excessively smooth at the highest refresh rate, and there is no cross-color.

2.3.3 Combination of drive system and control system

As the load of the circuit, the connection of the LED with the drive system and the control system is related to the stability of the entire display. Generally, there are three ways of series, parallel, and hybrid.

The series connection method is a low-reliability connection method. It is often used in low-end products. In the voltage stabilized drive circuit, when a certain LED is short-circuited, the voltage distributed to other LEDs will increase, which is likely to cause more damage.

The parallel connection method is suitable for products with low power supply voltage. In the constant current drive circuit, when a certain LED is disconnected, the current distributed to other LEDs will increase, which will easily damage all the LEDs on the circuit.

At present, in order to improve the reliability of the product, the hybrid connection method is generally used. The number of LEDs in series and parallel is evenly distributed, grouped in parallel, and then each group is connected in series. In this way, the voltage distributed on a string of LEDs is the same and passes through each LED. The current is basically the same, and the LED brightness is the same. At the same time, it is better to increase the negative feedback of the LED temperature in the constant current output to prevent the LED temperature from being too high.

The entire display screen is spliced by multiple module units. In order to ensure the reliability of power supply and data, the hybrid connection method must be adopted to realize the loop backup function. When a power supply fails abnormally, the other power supplies will automatically perform intelligence The current is equalized, so that the normal use of the system is not affected, and the trouble-free operation time of the system is more effectively improved, and the maintenance time of failure is reduced.

2.4 The special requirements of the conference camera on the screen

Although the high refresh rate can ensure that even under high-speed camera shooting, the large screen can still respond in a timely manner, and the picture transitions and transitions are smoother; but in the process of use, you will find that when the camera lens is aligned with the LED display, it will occasionally appear The inexplicable water wave-like stripes and strange colors, and with the change of the shooting angle and the adjustment of the camera lens focal length, the water ripple will also undergo some changes, which greatly affects the display effect of live broadcast and recording. This is brought about by the digitalization of TV cameras. Moiré phenomenon.

If the spatial frequency of the photosensitive element CCD (or CMOS) pixel is close to the spatial frequency of the (LED) stripes in the image, moiré will occur. Since the moiré phenomenon is caused by the inherent structure of the LED display, if one of the conditions for moiré generation—the grid structure of the LED display or the grid structure of the camera CCD (CMOS) disappears, theoretically Can completely eliminate moiré interference.

A domestic company superimposes a layer of optical treatment screen on the surface of the LED display screen. The screen is composed of a specific ratio of special light-absorbing material and surface bead lens coating. Through the use of optical screens, the LED screen changes from the original grid-like light Continuous surface light emission, by enlarging and displaying the discrete LED pixels, a continuous high-definition image is finally formed on the surface of the optical processing screen, which improves the contrast while retaining high definition and eliminating the moiré phenomenon.

If the user patiently read the above data information, I believe that they have a general impression of the quotation of the conference room led display, including the conference room led display model and size will be relatively familiar, not so unfamiliar, if there are any If you understand, you can contact Winbond Ying Optoelectronics, our company will give a more detailed meeting room LED display plan.