The Large-screen Projection Mosaic Of Color Uniformity Correction

Large screen projection display plays an important role in many areas. Among these technologies, the multi-projector display system is the most competitive and practical one, because of its better display effect lower cost and longer using life. So it occupies the most part of the large projection display market. Because the good color uniformity of the multi-projector display system is highly required by many practical applications, it becomes a crucial factor to evaluate the system's performance. This thesis focuses on the color uniformity of the multi-projector display system.First, the thesis introduces the most popular projection technology—TFT-LCD and DLP projection technology. It also introduces the multi-projector display technology and a representative multi-projector display system. In addition, it discusses the advantages and disadvantages of color uniform of TFT-LCD and DLP projection technology and gets the conclusion that DLP is the best technology for multi-projector display system.Second, the thesis discusses the chromatic theory in projection display system. Then it analyses the color uniform and brightness uniform of the DLP projector and propose the reason of the DLP multi-projector display system's color non-uniform. The reason is that at the same input gray level of the red green and blue color the different DLP projector in multi-projector display system has the different output brightness. Based on the analysis, propose a theory to tune AD (analog to digital) module and LUT (Look Up Table) module in DLP projector to make the output brightness equal in high gray level and make the chromatic equal in low gray level to correct the color uniform of the DLP multi-projector display system.Third, Based on the analysis above, a practical color uniform correction system is developed. Using the color uniform correction system to correct the 2x2 DLP multi-projector display system and analyses the result of color uniform correction. The result shows that the color uniform correction system has good performs and the system satisfies the requirements in practical projection.Finally, the conclusion and future research direction are given.