Simulation Analysis And Application Of SMD LED Cup Type

The semiconductor lighting based on light emitting diode(LED)has basically replaced the traditional lighting source as a new generation of lighting source,and has received extensive attention and research.LED packaging technology is the key link to realize the LED from the chip to the final lighting application products.It involves many fields,such as optics,heat,electricity,science,materials.technology and equipment,As an optoelectronic device,optical performance is the most direct indicator of LED packaging technology,and it is related to whether LED is energy efficient and whether it has high quality lighting effect.Therefore,the use of simulation design to optimize the packaging structure and improve the optical performance of LED is becoming the research hotspot at present.The optimization design of the package structure is related to the packaging manufacturing process.It is very important to realize the high optical performance of LED by solving the key problems in the existing packaging technology and using the optimized package structure and developing the new process methods.In this paper,several key issues in optical simulation design and manufacturing process of LED packaging are studied and the following results are obtained:The packaging structure of LED is analyzed and the packaging structure which has an influence on the optical parameters in the package structure is described in detail.The optical parameters of the materials in each layer of the LED chip are analyzed and summarized,and a reasonable simplification is made to meet the requirements of the simulation on the basis of satisfying the theoretical model;the Mie scattering can be achieved.The theory is applied to the theoretical calculation of the light scattering and absorption characteristics of YAG phosphors.The simulation analysis of the common YAG phosphors on the world has been carried out to achieve the simulation require-ments.The refractive index of the commonly used packaging materials,such as epoxy resin/AB adhesive,is analyzed,and the diffuse reflection characteristics of the surface scatterer(plastic wall)are studied and analyzed.The ABg model is used to verify the simulation.On this basis,a simplified LED packaging structure simulation method is proposed.Based on the simplified LED packaging structure simulation method,the software design of automatic optimization cup type is carried out.Through this software,the automatic generation of LED packaging model,the automatic addition of various optical parameters,automatic simulation and simulation results,such as light flux,light intensity distribution,color temperature,color and so on,can be obtained,and the cup type can be continuously changed.Parameters get the best cup size of the demand,saving designers a lot of time.The simulation method of LED packaging structure and the software of LED automatic optimization cup type are given.The highest luminous flux cup type parameters of 3835SMD LED with the same color temperature are obtained under the condition of the corresponding chip and phosphor.The LED cup parameters are simulated and verified with the actual products,which verifies the accuracy of the simulation.The simulation results and experimental results show that the luminous flux can be increased by about 5%through the change of cup type.This simulation scheme can reduce designers'repetitive work,standardize the use process,reduce misoperation and save designers'time.In the application of SMD,the shooting lamp is one of the most extensive applications.The common TIR lens is summarized and analyzed.The lens design of the point light source and the extended light source is carried out by the differential equation method and the SMS(synchronous free surface)method.It also points out the points for attention in the design of TIR lenses.A general design method is put forward.