|LED display screen basics information and knowledge|
1. The growth period of LED display before 1990. On the one hand, due to the limitation of LED material devices, the application field of LED display screens has not been widely developed. On the other hand, display screen control technology is basically a communication control method, which objectively affects the display effect. The LED display in this period is widely used in foreign countries. There are few domestic products. The products are mainly red and green. The control method is communication control. The gray level is single point and 4 level gray, and the cost of the product is relatively high.
2. From 1990 to 1995, this stage was a period of rapid development of LED displays. In the 1990s, the global information industry grew at a high speed, and information technology continued to break through in various fields. LED displays have also seen new results in LED materials and control technologies. The development of blue LED chips has been successful, and full-color LED displays have entered the market. In the field of electronic computers and microelectronics, video control technology has appeared in the field of display control technology. The gray level of display screens is 16 gray levels and 64 levels. Grayscale graying, the dynamic display effect of the display is greatly improved. At this stage, the LED display speed is developing very fast in China. From the initial few enterprises, the annual output value is tens of millions of yuan to dozens of enterprises, the annual output value is several hundred million yuan. The product application fields involve financial securities, sports and airports. , railways, stations, road traffic, commercial advertising, postal and telecommunications and many other fields, especially the development of the securities stock industry in 1993 has led to a substantial increase in the LED display market. The mainstream product situation in the field of LED display panel display has basically taken shape, and the LED display industry has become an emerging high-tech industry.
3. Since 1995, the development of LED display has entered a period of overall steadily improving the adjustment of the industrial structure. Since 1995, the internal competition of the LED display industry has intensified, and many small and medium-sized enterprises have been formed. The prices of products have fallen sharply, the application fields are broader, and a series of new problems have appeared in the quality and standardization of the products. The development has been paid attention to and has been properly regulated and guided. At present, the work in this area is gradually deepening.
LED screen status
2006 sales of more than 100 million enterprises? Shanghai Sansi Technology Development Co., Ltd.? Nanjing Luopu Co., Ltd.? Nanjing Handerson Electronics Co., Ltd.? Beijing Liad Electronic Technology Co., Ltd.? Beijing Century Chengtong Electronics Co., Ltd.? Huizhou Desai Optoelectronics Technology Co., Ltd.? BOE Intelligent Display Technology Co., Ltd.? Shenzhen Ruituo Display Technology Co., Ltd.? Shenzhen Lanpu Technology Co., Ltd.? Shenzhen Pune Optoelectronics Technology Co., Ltd.? Shenzhen Lianchuang Jianhe Photoelectric Co., Ltd.
In 2006, the backbone enterprises in the industry continued to develop and improve. Huizhou Desai: the production capacity has increased and become the main processing base for the export of LED display products in China; Beijing Century Chengtong: infrastructure construction, forming the professional processing capacity of LED display, and jumping to the forefront of the industry; Shenzhen Ruituo, Shenzhen Lanpu, Shenzhen Dolly Group and other enterprises: integrated development in LED devices and display products, and become a large-scale LED display application product supplier in the industry; Shanghai Xinmao completed the transformation and structural adjustment, laying the foundation for future development; Xi'an Qingsong, Nanjing Luo Pu, Tongzhou Electronics, Nanjing Handerson and other enterprises: on the basis of LED display business, expand the business of other display products or systems, forming a basis for sustainable development.
The origin of 16-bit constant current IC: The two-color screen is mainly based on display text, and the single-chip scanning is convenient. Due to the increase in the number of LEDs, in order to save resources, the 74HC595 shift scan is cited. In order to be more suitable for LED applications, the constant current setting function is integrated on this basis, and 16-bit devices are packaged in accordance with the requirements and cost requirements, and are widely used in current full-color screens.
Generally, how the LED large screen low frequency flickers, because the LED itself does not have the characteristics of afterglow effect, so the refresh rate of the LED screen using the traditional constant current source pulse width adjustment gray scale must be greater than 120 Hz to achieve flicker-free image display. . Therefore, it is necessary to perform up-converting of the image signal of the eight-frame frequency with lower gray-scale data, and the result is that the refresh data has great redundancy, which increases the hardware overhead of the LED driver board.
At present, many control systems of Nanjing Depuda Technology Industrial Co., Ltd. and Shenzhen Lingxingyu Technology Development Co., Ltd. are used in the market. Detailed information can be viewed or consulted on the above company website.