Research And Design Of Microstructure Characteristics And LED Backlight Modules

Liquid crystal display(LCD)technology has covered almost all applications fields today.Among them,LED backlight technology is one of the key technologies of LCD technology.In recent years,due to the ultra-thin challenges brought by new display technologies such as OLED and Laser,lighter and thinner has become an urgent problem in LCD technology.LED edge-lit backlight module has potential to realize further ultra-thin design by optical design because of its multilayer films and optical characteristics.The traditional LED edge-lit backlight often have one scattering film and two brightness enhancing films(BEFs).Although those films help to improve the illuminance,it has a certain thickness and a degree of loss of light energy.This two features are incompatible with the development trend of environmentfriendly society and ultra-thin module.In this paper,according to the principle of light emission from the LED edge-lit backlight,we acquire a new LED edge-lit backlight by designing the optimal micro-prism distribution on the bottom surface of light guide plate(LGP).The goal of this design is to achieve a high luminance uniformity and high light energy utilization of the backlight module without scattering film.This paper proposes a new one-dimensional micro-prism arrangement density method.We choose the classical Low Discrepancy Sequence(LDS)as generator,which is combined with the uniform distribution theory.After the v-cut technology is added,a new LED edge-lit backlight with micro-prisms LGP design method is complete.This design method can achieve high luminance and high light energy utilization.The main research work is as follows: 1.This article describes the development of LCD technology and the challenges faced currently.By setting LED edge-lit backlight design as the solution to the challenges problems,a large number of researches have been conducted on the scattering dot pattern and microstructures.2.According to the analysis of the light emitting principle by the dot pattern and microstructures,we use the non-imaging optics concept to discuss the feasibility of the LED edge-lit backlight optical result about uniform and small emitting angle.After the reasonable analysis,microstructure type LGP design is set to be the focus of this paper.3.After analyzing the principle of total reflection of the rays inner LGP,the core theoretical model of scattering dot patterns is detailed.We also summarize the general microstructure design ideas to provide a theoretical basis for the new method proposed follow.4.The interaction between the micro-prisms and the rays is analyzed.And we find that the arrangement position of the micro-prisms has a major influence on the emitting light distribution of LGP.We also find that when designing an arbitrary size backlight,the original density formula of one-dimension micro-prism has difficult to set multiple specific initial values simultaneously.5.We propose a new method based on probability analysis and have a comparison between pseudorandom sequence and the quasi-random sequence.The uniform distribution theory was combined with our new density and Hamilton generator.The V-cut distance is added as well.After the combination,a new one-dimensional micro-prisms distribution generation method is formed.6.We design three typical type of small and medium size LED edge-lit backlight modules for verification,such 2.7inch,7inch and 14 inch.We also design 2.7inch classical backlight module for comparison.Simulations have showed that the modules design by our new method obtained some good optical results.The maximum luminance uniformity and maximum optical efficiency are 92.2% and 80.0%,respectively.Compared to the classical backlight module with scattering dot pattern,the light energy utilization ratio of module A is 1.89 times,and the brightness uniformity is 0.98 times.Backlight module with microstructures has advantage in high light utilization refer to backlight module with scattering dot pattern.Our design method has proved to be feasible and suitable for the low-cost and ultra-thin development trend of small and medium sized LED backlight design.