Mosaic Display Color Uniformity

In our daily life, large screen displays play a very important role in many areas, such as commercial conferences, advertisements and industrial control. The DLP (Digital Light Processing) display wall is a very practical way to realize big screen display;it's made up of several DLP engines;DLP engines have many advantages such as high luminance, high definition, long longevity, and so on. Color uniformity is an important index to evaluate the display quality of DLP display wall. Because of DLP display wall's own characters, the color uniformity between the different DLP engines must be very high. So, the main content of this thesis is mainly about the adjustment of the DLP display wall's color uniformity.First of all, this thesis introduces several modern display techniques, such as CRT(Cathode Ray Tube) displays, PDP(Plasma Display Panel) displays, LCD(Liquid Crystal Display) displays, and so on;especially introduces the DLP projection technology, compares DLP projection technology with LCD/CRT and other projection technologies, discusses and compares different color combination technologies;at the same time, this thesis also introduces the main situation of the DLP display wall's development.The second part of this thesis discusses the measurement of DLP display wall's color uniformity. To measure the DLP display wall's color uniformity, CIE 1964 Uniform Color Space is adopted. This thesis analyses the color uniformity of the DLP display wall, and proposes two methods to adjust the tricolor coordinate and the luminance uniformity of white.Based on the discussion above, the third part of this thesis first proposes a method to adjust the tricolor coordinate to improve the color uniformity of the screen, and then builds a system to adjust the luminance uniformity of white. The system uses a two-dimensional CCD to measure the luminance of the screen, and then adjust the luminance and proportion of red/green/blue to improve the color uniformity of the screen. The result of experiments validates that this system can measure and adjust the color uniformity of DLP display wallaccurately;the system can be applied in the production of DLP display wall.