本文建立了一種光學測量系統，以測量使用選擇性激光熔化製成的Inconel 718樣品的表面粗糙度和輪廓。使用一張含有紅色、綠色和藍色的條紋的影像同時測量物體的表面粗糙度，形狀和高度差。為了準確識別圖像中的工件和金屬粉末或基材，本研究使用邊緣檢測方法來檢測出工件的形狀和位置。條紋投影和三步相移用來測量工件的形狀和高度差，並使用梅西展開法計算高度差，且建立了3D影像。由金屬的不平坦表面引起的光反射在圖像的不同位置處導致不同的強度，而影像的灰階強度被使用於計算平均強度，並且與粗糙度比較並觀察其趨勢。最終，該系統有望監測到每個固化層的表面粗糙度條件；金屬粉末的表面粗糙度條件；及固化層的輪廓和固化層與金屬粉末之間的高度差同時出現。最後使用橢圓形工件來證明此光學計量系統的可行性。最終結果為: 物體檢測可以檢測物體的邊緣，而能在影像上只顯示待測物。高度測量值與高度實際值的誤差可以在10%以內。使用計算的灰階強度在粗糙度0~10 (μm)的範圍內有相同趨勢。

In this thesis, an optical metrology system is established to measure the surface roughness and profile of Inconel 718 samples made by selective laser melting. The color image with red, green and blue fringes of the object were used to simultaneously measure the surface roughness, shape and height difference of an object. In order to accurately identify the 3D workpiece in the image, this research uses edge detection method to detect the shape and position of the object. The shape and height difference of the object are measured by using fringe projection and three-step phase shifting, and the Macy expansion method is used to calculate the height difference. The light reflection caused by the uneven surface of the metal causes the different light intensity at different positions of the image and then the light intensity is used to calculate the average intensity and autocorrelation. The intensity and autocorrelation are compared with roughness and similar trends are observed. Finally, this system is expected to simultaneously monitor the surface roughness of each solidified layer, the surface roughness of the metal powder, the outline of the solidified layer, and the height difference between the solidified layer and the metal powder. In the end, the oval sample was used for measurement to prove the feasibility of this optical metrology system. As a result, object detection can detect the edge of the object and only the object to be measured can be displayed on the image. The error of using the system to measure height can be within 10%. The average intensity measured by the system has the same trend when the roughness is less than 10 μm.

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