The Application Of LCOS Projection Display Based On The LED Lighting Design

LED as the projector light source is up to the minute to the whole world, and LCOS is a promising technology for using in micro display by bring high resolution, high brightness and low cost to customer. This project will propose the high brightness and colorful LED source applied in LCOS micro display system for the purpose of resolving the problems caused by traditional source. In this paper will complete an new driving circuit of the LED and associated controlling and protection circuit.First,the structure, optical principle and main stream of high-power LED are introduced. The micro display technology and LCOS optical engine are studied. The components that make up the system and the merits brought by the new structure are analyzed. Highlight the advantages of using LED in LCOS micro display are explained.Then,the theory of the light, vision and chroma is also presented , which is very important in the process of projection display.At last,a detailed analysis is carried out with the performance of the high brightness LED, and will be achieved the dedicated circuit design at the point of LED's performance. The principle of several driving method are analyzed and the specific parameters of the circuit are calculated in detail. The principle of PWM signals adjusting LED bright is analyzed, and a new type of heat pipe radiator is explained, the thermal problem of high brightness LED is solved. All of the designs are working in order to ensure the stability of LED.And optical calculation with the pre-set value on the RPTV is accomplished in this paper, and complete the prototype machine. The specific parameters are measured and the performance are analyzed of the prototype machine.In this thesis, the tests on the LED module and the whole set outputting have been carried out, which demonstrate that, the output current of LED driving is linearly varying from 10A to 30A; the voltage of RGB three-colored LED is 2.9V, 5.4V and 5.1V, respectively; the current ripple on the driving is less than 10%. The data above indicates that the LED could be kept in normal statement as the design. In addition, luminous flux of the three-colored LED is more than 4200lm. After all, the measurements of the whole set are: the maximum illumination is 83.7cd/m2, the minimum illumination is 65.3cd/m2; the homogeneity is about 78%; the outputting is about 50ANTI lm; color gamut is more than 90%.The illumination module of LED has been analyzed on both the calculation and the experiment. There is the difference between the calculation and the actual. However, such difference is meaningful to the high-luminance LED for LCOS-HDTV, and is fundamental to the further development.