LED Projection Illumination System Design Of High Luminous Efficiency And Wide Color Gamut

With the continuous improvement of LED luminous efficiency,high-power LEDs are gradually applied to the projection system.The illumination system based on the three-color LEDs and the light-rod has the advantages of small size and wide color gamut.However LED has the big problem of large emitting,which leads to low projection brightness.This thesis utilizes the Etendue matching principle and non-imaging optics theory to design the LED illumination system with high luminous efficiency and wide color gamut to match the subsequent projection system,which could improve the energy utilization rate of the whole system and enlarge the color gamut of the projection system.Based on the characteristics of LED light source and non-imaging optics theory,this thesis puts forward the overall design idea and design method of LED and light-rod based illumination light path.The luminous flux of red,green and blue LEDs is calculated theoretically.Based on the optical characteristics of chosen LEDs,the collimators designed by two different methods are applied.According to the characteristics of the follow-up display system and the reverse design method,two kinds of the collectors matching with the collimators are designed.Based on the principle of Etendue conservation,the conical light-rod is designed.Based the design parameters of each components,the simulation model of two kinds of LED and light-rod based illumination system is established in LightTools.The simulation results are verified and analyzed.One kind of the collimator and collector with the best simulated results is selected and processed.The actual illumination system is built and assembled with the follow-up optical system into a projector for the actual test.The experimental test results show that the design of the LED and light-rod based illumination system realizes the efficient collection and uniformity of the LED rays.The color gamut reaches 75% of NTSC standard.At the same time,the luminance of the projector that using the designed illumination system increases by 16.9% than the common LED projector in market.The energy utilization efficiency of the designed system is efficiently improved.The designed LED and light-rod based illumination system can satisfy the requirements of high luminous efficiency and wide color gamut.