Side-emitting And Flat-panel LED Backlight Design And Optimization

Energy has become a global problem impacting human development, light emitting diode technology has been recognized as one of the most promising high-tech at the 21st century, LED industry have been rapidly expanding with its application field extending. As a major market of LED industry, the LED backlight modules demand for LCD is also growing. With the LED backlight developing to the direction of lighter and thinner, side-emitting LED backlight has become the mainstream of the market. The network distribution on the bottom of the LGP plays an important role to the surface brightness, uniformity and other optical properties of LCD. In this paper, the backlight module was designed and simulated starting from the design of the light guide plate according to the principle of the side-emitting LED backlight,The network distribution on the bottom of the LGP plays an important role to the surface brightness, uniformity and other optical properties of LCD. Original LGP network design theory and methods are not yet mature on the production of the network, or aimed at light guide using linear light source, or aimed at LED light package structure and LED bar structure design, achieving a linear source result. Complex zoning regulations will waste more time. In this paper, the transmission process of the light crossing the light guide plate was analyzed and a calculating method of the net dot distribution was deduced according to the illumination distribution of LED. Besides, the mode was modeling and simulated. The algorithm was preliminary verified and the result was analyzed.For the problem in the simulated result, the network distribution was optimized using four methods respectively, which are increasing network density, increasing the dot radius and adjusting the dot height and adjustment with zoning. The uniformity of the backlight module was all simulated at 85% approximately. The prim film was optimized according to its bright enhance principle and parameters'effect on the light. Then the light utilization rate of the backlight unit was increased to 77.2% at the premise of surface brightness uniformity is essentially the same as before. Then the algorithm was further verified.Finally, a light guide model was made and tested. The net dot was curved by the laser machine. Then the illumination uniformity was tested. By analyzing the test result, it was concluded that the uniformity of the backlight model is roughly consistent with the simulation result, while the light efficiency which is influenced by the LGP quality and LED light source etc. is lower than the simulation result.