多投影式光場三維顯示系統成像品質之優化

Abstract

光場顯示作為一種新興的三維顯示技術,相較於其它裸眼式立體顯示技術而言，此技術由於可以提供細膩的水平視差及連續的運動視差，所以近年來已經變成研究的熱點之一。然而，對多投影式的空間多工水平光場平面顯示器來說，在實際的應用系統中，由於觀看視角、投影機陣列和散射螢幕角度的影響，會造成在成像過程中由於斜向投影而導致影像的失真變形及顯示器亮度不均等問題, 進而影響到觀看的品質。 本論文針對以上問題首先分析了造成影像失真的原因；然後提出了一種成像品質優化演算法，該演算法通過變換調整影像源的成像位置對所成影像進行修正，達到優化成像品質的目的；之後用C++實現了該優化演算法，並將其應用於實際系統中。實驗結果表明，修正後的影像較修正前的影像有了明顯的改善。此外，我們也提出了一個形變度量的演算法，用於量化及比較影像形變修正前及修正後的結果。最後，針對了顯示系統亮度不均的問題，提出了一種亮度均勻化演算法，並編寫了相應的實現程序，以提升成像的顯示品質。

As an emerging 3D display system, when compared to other auto-stereoscopic displays, light field display can not only provide the continuous motion parallax, but also the delicate horizontal parallax, so it has become one of the research hotspots. However, there are problems that affect the image quality such as the distortion of the image caused by the oblique projection and uneven brightness due to the viewing angle of the receiver, and the arrangement of projectors for the multi-projector-type horizontal light field displays. In this paper, we first analyze the causes of image distortion, and then propose a method, which corrects the image by adjusting the imaging positions of the image sources, to achieve the purpose of optimizing the image quality. C++ is used to implement the proposed algorithm, and the optimized image sources are applied to the actual system for projection. The experimental results show that the corrected image has a significant improvement compared with the uncorrected one. In addition, we have proposed a deformation metric algorithm for quantifying and comparing the projection results for the corrected and uncorrected images. Finally, a brightness equalization algorithm with the corresponding realization program is proposed, to enhance the brightness uniformity of the system.