近年來由於三維列印(3D printing)的普及化，讓原本只有專業人士才能使用的技術，逐漸融入大眾生活中。三維列印可用來協助製作實體物件，例如客製化公仔、設計概念模型、複雜結構元件等。然而，現階段彩色三維列印仍未普及，針對某些需要精準顏色輸出的應用情境仍無法滿足。為了達到彩色三維列印的目標，近年來有不少學者與廠商投入相關技術的研發。目前市面上的全彩三維列印切層色彩主要是透過切層表面輪廓的色彩往內部延伸而獲得，故咸少考慮三維方向性對顏色之影響。
本論文研究針對多噴頭塑形(Multi-Jet Modeling)的成型方式進行切層演算法設計。根據成型方式與材料的特性，將彩色三維模型進行體素(Voxel)切層。並將模型表面之三維方向性的色彩資料都納入考量，最後每個體素位置被賦予色彩資訊，以提供彩色切層資料給三維列印進行模型輸出。本研究分成三種的彩色切層演算法，其一為透過體素與頂點之間的關係進行顏色混和，其中又可分為平均混色與加權混色兩種模式。其二為將第一種的平均混色方法將取樣樣本中雜訊移除，去除色差大的取樣，以便重新取得較為一致的混色結果。其三為指定距離體素最近網格為基準，進行去除色差大頂點進行演算。挑選不同性質三維模型，包含色彩多樣性與紋理複雜程度，並進行上述之演算法測試。實驗結果發現，方法三以最近點之色彩為主考量之演算法可產生較佳之混色效果。

In recent years, three-dimension printing (3D printing) becomes more and more popular, it makes gradual integration for not only professional users but common users into public life. 3D printing is currently utilized for producing real objects, including customized dolls, design concept models, complex structure objects et. al.. However, color 3D printing is not widely used, particularly for those need high quality color 3D printing. In order to achieve the goal of 3D printing, many scholars and companies have put efforts on developing related works. Currently, most products in color 3D printing only use the contour-color on each sliced-layer for color processing which does not consider the changing color appearance due to 3D geometry.
This research develops 3D model slicing methods which is favor to Multi-Jet Modeling (MJM) type 3D printing. These methods, which consider the shape-forming and material property, will slice color 3D models into color voxels. Based on directional behaviors of 3D color, we assign a color which blended from neighboring vertexes’ colors to each voxel as an output data format of MJM 3D printers. The research provides three methods for slicing color 3D models. The first is to blend the color which utilizes the relationship between the voxel and its neighboring vertexes. In this method, two types, that are blending by averaging colors and blending by weighting colors, are proposed. The second method is similar to the first one with additional statistical filter, which will remove the noise from sampling colors and make color consistent. The third method is utilizing the distance priority of neighboring vertexes. In the case, the nearest vertex’s color will be firstly considered as the final color of the voxel. We carry out the previous methods and apply them into different type 3D models, including different color varieties and different pattern repeatability. The result shows the recommended method is the third method which considers the distance priority.

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