Since the LED display screen is a comprehensive computer network information system with complex functions, it is a relatively complicated process to conduct a comprehensive acceptance. The completion acceptance of the system will not be carried out until after the project is installed and debugged for a period of time.
In order to ensure the quality of components, display products and construction, and at the same time simplify the local acceptance process, we recommend that the bidder conduct the following acceptance checks on the products during the entire project period:
1.1 Bar DJ special-shaped screen P2 LED display experience collection
This is the acceptance of the hardware technology design quality in the HOLA-LED production plant. The main items of acceptance include:
1) Acceptance of display system engineering
The acceptance work can be divided into three parts, namely the acceptance of the construction documents, the acceptance of the system communication characteristics, and the acceptance of the compliance with the construction standards during the construction.
The construction document mainly includes four parts:
Design drawings: overall structure diagram, independent system structure diagram, etc.
Construction drawings: wiring pipeline construction drawings, system topological structure drawings, elevation structure drawings, wiring room equipment drawings, etc.
Construction records and as-built drawings
testing report
Maintenance documents: operating instructions, maintenance instructions, other necessary installation and maintenance records, etc.
The main content of the construction status acceptance work is to check whether the construction of the display system meets the engineering specifications, especially the installation method of the display screen, various technical parameters, and protection conditions.
1.1.1 Acceptance of key material LED:
Acceptance of important LED performance such as brightness, wavelength, viewing angle, etc.
1.1.2 Grayscale acceptance
To display an image, the luminous brightness of each LED constituting the pixel must be adjustable, and the fineness of the adjustment is the gray level of the display screen. The higher the gray level, the more delicate the displayed image, the richer the color, and the more complicated the corresponding display control system. Generally, 256-level grayscale images have very soft color transitions, and our company uses a dedicated display control chip for LED screens, which improves the display effect and stability of LED screens to a higher level.
The dedicated display and control chip for LED screens is a super-large-scale ASIC, which not only contains all the logic required for LED display, but also replaces a large number of small-scale ICs in traditional designs. Each chip also has 128 pulse width modulation type grayscale controllers to realize the inverse gamma correction, so that the grayscale display conforms to the biological principle of 8192 grayscale control.
This kind of gray-scale control with visual correction is more suitable for the human eye’s intuitive perception of brightness. It gives people a subjective feeling that the gray levels are clear and the colors are lifelike, which cannot be achieved by any LED screen in the past.
1.1.3 Display effect acceptance
The core performance index of LED display is the brightness or gray level achieved for each primary color (red, green, blue). The current international display standard requires each primary color to achieve visual 256 gray levels. The built-in processing logic of the dedicated display and control chip for the LED screen can output 8192 levels of gray, and select the 256-level gray output that fits the CRT display to make the overall image effect clearer, more lifelike and fuller of appeal.
In addition to the gray level, the other two performance indicators of the display screen are its resolution and refresh rate. Due to the characteristics and requirements of the LED display itself, traditional solutions often have to lose one or two of the standards as the cost of improving another index.
Since the data output of each pin of the dedicated display control chip for LED screens reaches 1 trillion per second, which far exceeds the data output capacity of the traditional solution, this problem is fundamentally solved. The dedicated display and control chip system for LED screens can simultaneously support 1024*768 screen resolution and up to 180Hz screen refresh rate, far exceeding the performance indicators of traditional solutions, making the display screen stable, flicker-free, and non-smearing.
1.2 Application software function acceptance
The main purpose of these acceptance checks is to check whether the system functions are fully realized, whether the system operation performance is satisfactory, whether the interface meets the specifications and the requirements of the tenderer, and whether the overall system is stable and reliable.
1.3 Simulation system acceptance
This acceptance is the acceptance of the production process quality of the product in the production plant. The main content of the acceptance includes:
·The overall quality of the product
·Color uniformity
·Technology level
·Exterior
The objects of acceptance include display screen products, control components, power distribution cabinets, frames, etc. The acceptance procedure is carried out on a simulation system set up in the factory. For the detailed acceptance procedures and acceptance indicators of this part, we will provide the factory inspection conditions of the products for reference.
1.4 Frame installation quality acceptance
This acceptance is the acceptance of the process quality of frame installation and screen component installation at the construction site. The main content of acceptance includes:
·Overall appearance
·Flatness
·The rationality of the structure
·Operability of maintenance
