光纖束設計應用於雷射位準儀中之光整束元件

Abstract

本論文目的為模擬、設計、製造、量測一個光纖束/毛細管束元件。該元件能將打入元件的一個點雷射光源轉換成360展開之雷射參考線。該雷射參考線能應用於土木工程之準直標線的光學需求。首先，四個旋轉式及兩個固定式之雷射墨線儀專利在第一章中回顧討論。接著為設計光纖束而簡化的四個變數在一系列光學模擬中最佳化。這四個變數為:1.單根光纖中的核心數2.各個核心的直徑大小3.核心之間的間距4.核心/包覆層之材料折射率。模擬結果顯示出，光纖束元件的雷射散射表現大部分取決於單根光纖中的核心數以及核心/包覆層材料折射率。各個核心的直徑大小不影響其表現。核心間的距離在相等於核心直徑時最佳化。當最佳化之參數於模擬中取得後，有三種毛細管束被製造並且量測比較結果。分別是UV膠填充15mm管徑、UV膠填充8mm管徑，未填充中空之8mm毛細管束。三者中前二者因管束內毛細管排列不平行造成投射出之雷射線變寬並且模糊，只有第三個中空8mm毛細管束維持原有之雷射線寬並有良好均勻度表現，並且有簡單便宜之製造方法而能符合預期目標。

This assay aims to simulate, design, fabricate and measure a simpler, cheaper laser beam shaping bundle which can project an omni-directional laser line by input a laser spot onto the fiber/capillary bundle. In this assay, four rotational and two static omni-directional laser beam shaping patents were reviewed in introduction. A series of ray tracing simulations were then modeled and executed to estimate the influences of four bundle design parameters: 1.Cylinder count in one bundle 2. Diameter of each cylinder 3. Cylinder cores spacing 4. Core/space refraction index. The simulation results indicate that cylinder count dominates the dispersion pattern when more cores lead to brighter back side and darker front side. The diameter has no influence. The core spacing will be optimal when equals to core diameter. After optimal parameters being choose by simulations, three types of capillary bundles were made out and measured by an omni-directional light measurement system. The laser line make by three type of bundle are snapshot and compared then discussed the reasoning. Finally the best performance 8mm hollow bundle has highly uniformity and simple low cost fabrication process which fits the original goal.