本論文利用兩種方式設計光學元件，使高準直光源經由此光學元件轉變為點陣圖之特殊結構，期望應用於3D掃描辨識系統，以達到結構光技術之高精度及快速掃描之特點。本研究中使用632nm的準直光源作設計，計畫在距離50公分處打出60*60cm的結構點陣圖，結構設計為100*100的矩形點陣，點與點之間的距離為0.6mm。 設計方式分為兩種，第一種設計方式是採用迭代傅立葉演算法計算出原始光場與最終結果中間的相位繞射光學元件，進行約300次的迭代逼近收斂，接著將此繞射光學元件進行八階量化，設計結果為繞射效率達77%，信躁比(SNR)為27.8dB，繞射圖形與目標圖形相符，在繞射區域內有100*100個點數。 第二種方式是採用微透鏡陣列設計，準直光源經過此微透鏡陣列時，會被對應之微透鏡聚焦，在焦平面處形成數個微小光斑，這些光斑再進行干涉與繞射，並在遠場產生期望之矩形點陣。微透鏡之週期影響結構光之密度，焦平面光斑大小影響屏幕成像面大小。設計結果為目標區域能量占總共93%，其餘能量損失於周圍較不清楚的點陣。 本研究建立了兩種方法設計光學元件用來產生結構點陣光，可因應不同需求做選擇設計。繞射光學元件的設計自由度高，除了本研究中的矩形點陣，也可以設計特殊織結構光。微透鏡陣列設計快速，不須經由複雜的傅立葉運算，可快速得知設計需求，並且相對容易製造。 ;In this thesis, we used two methods to design optical components. Converting a high-collimation light source into a special structured light of a dot array through the optical element. To achieve the high precision of structured light technology and the characteristics of fast scanning. In this study, using 632 nm collimated light source for design. Planning to produce a 60*60cm structure dot pattern at a distance of 50 cm. The structure was designed as a 100*100 rectangular dot matrix with a distance of 0.6 mm between each point. Design method is divided into two, the first design approach is to use an Iterative Fourier transform algorithm to calculate the phase diffraction optical element between the original light field and the final result. An iterative approximation convergence of about 300 is performed. Then quantizing the diffractive optical element. The design result is a diffraction efficiency of 77% and a signal-to-noise ratio of 27.8dB. The diffraction pattern matches the target pattern and has 100*100 points in the diffraction area. The second way is to use a microlens array. When the collimated light source passes through the lens array, it will be focused by the corresponding lens. These spots produced at the focal plane conduct Interference and diffraction, and produce the dot array in the far field. The period of the microlens affects the density of the structured light, and the focal plane spot size affects the screen image size. The design result is that the target area energy accounts for 93% of the total, and the rest of the energy is lost to the surrounding unclear lattice. This study established two methods to design optical components to generate structural light, which can be selected according to different needs. The design freedom of the diffractive optical element is high, and in addition to the rectangular lattice in this study, special woven structure light can also be designed. The microlens array is designed to be fast, without the need for complex Fourier operations, to quickly understand design requirements and is relatively easy to manufacture.
