開發雷射直寫技術設備及其應用

Development of laser direct writing technology equipment and its application

呂紹弘(Shao Hung Lu)

指導教授 ： 李有璋

中原大學/工學院/機械工程研究所/碩士(2021年)

https://doi.org/10.6840/cycu202100776

摘要

本論文以自行設計開發的光固化3D列印機台為主要製程設備，在三軸列印的架設以5相步進馬達搭配滾珠螺桿連接X、Y軸形成移動平台，並加上線性馬達連接升降載台完成Z軸架設。在程式控制上，以GRBL作為三軸控制軟體，搭配Arduino MEGA2560單晶片微處理器輸出訊號給各軸馬達驅動器以及雷射光源模組來控制三軸移動和固化樹酯所需的雷射功率大小，並由人機介面即時監控機台目前狀況。接著依據實際打印結果調整列印參數和硬體設定，逐步改善列印品質，包含選用的馬達、馬達驅動器、模型切片軟體，使其成為最小列印線寬2 m的3D列印機台。
接著使用該機台列印菲涅耳波帶片模板，列印出內圈半徑161 m，外圈半徑1007 m的20環同心圓，經過PDMS複製模板結果，再以樹酯為材料翻模至蓋玻片上，完成波帶片製作。在製程方法克服列印載台與樹酯槽底並非完全平行，導致列印結構厚度不均的問題；最後探討波帶片的光學聚焦效果，藉由改變列印底板形式，從間隔10 m的柵狀底板改為間隔5 m的圓形底板，其聚焦能量因此提升了53%，接著比較不同層高之間的波帶片對理論聚焦距離的影響。從實驗結果得知，製作出越薄的波帶片越能接近理論值，但需考量製作的材料是否會因厚度降低變得透光，而失去原先預期的光學效果，最後依據實驗結果表示，層高4 m的波帶片能夠獲得最佳效果。

關鍵字

雷射直寫技術

並列摘要

In this study, an UV-cured micro-sized 3D printer to fabricate the Fresnel zone plate (FZP) was developed. The printer can be mainly divided into three parts, UV laser focusing module, electrical control module, and X-Y-Z translation module. In the electrical control module, Arduino MEGA2560 was used to control the laser power, two stepper motors (X-Y translation), and one linear motor (Z-translation), the software LaserGRBL was used as for the human machine interface monitoring the current status and also changing the printing parameters on the 3D printer. The smallest line width that this 3D printer can do is approximately 2 m.
Next, the 3D printer was used to fabricate the imprinting epoxy mold of the Fresnel zone plate, which the structure was 20 concentric circles with inner radius 161 m and outer radius 1007 m. A flexible PDMS (Polydimethylsiloxane) mold was used to duplicate the epoxy mold for a thermal embossing process to fabricate the Fresnel zone plate. During the printing process, I noticed the build plate and the bottom of the resin tank are not parallel, this may cause the inconsistent printing thickness. In order to solve the problem, a bottom plate before the FZP mold was printed first, the bottom plate pattern with the concentric circles with 5 m gaps increased 53% of focusing energy than the grating pattern with 10 m gaps. The thickness of the zone plate also influence the focusing performance, in my study the thickness of 4 m is best match to the theorical value.

並列關鍵字

laser direct writing technology

參考文獻

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