透明材質表面形貌高速量測系統的研製

Development of a High Speed Surface Profile Measurement System for Transparent Materials

蘇冠霖(Guan-Lin Su)

指導教授 ： 章明

中原大學/工學院/機械工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000136

摘要

本研究之目的是要建立一套非接觸式大範圍透明材質表面形貌的快速量測系統。系統由高速攝影機、外部觸發裝置、 LED光源及高精度Z軸位移裝置所組成。量測以Mirau型干涉顯微鏡為基礎結合自動對焦技術，利用聚焦形貌法的原理及低同調光只有在兩光程相近時才會形成干涉的特性，增強透明材質或平滑表面在聚焦時影像的高頻訊號，除此之外，還使用了質心法來計算聚焦峰值的位置，提升量測解析度。使用點量測的方式，配合X、Y軸位移平台，可實現待測物局部微形貌與大範圍表面形貌的量測。以20倍Mirau 干涉物鏡進行量測時，水平解析度為0.335μm，縱向解析度為8nm。本系統單點垂直掃描定位時間取決於取樣間距與掃描深度，一般約為0.1~2.5秒，量測範圍則取決於使用之平台尺寸，垂直掃描範圍可達20mm。

關鍵字

干涉顯微鏡 ； 透明材質 ； 表面形貌量測 ； 自動對焦 ； 質心法

並列摘要

The main purpose of this thesis is to develop a rapid profile measurement system for transparent materials. This system consists of a high speed camera, a trigger system, a LED light source, and a high precision translational stage moved in vertical direction (Z-axis). The measuring is based on a Mirau type microscopic interferometer and an auto-focusing technique. Using the idea of shape from focus and the characteristic of interference forming only when the optical path of the two beams of low coherent light is close, it boosts the high-frequency signal at focusing position of transparent materials. In addition, the centroid method is also used in the peak grab of interference pattern to improve the focus measurement resolution. Experiments were carried out with both micro profile evaluation for a small area and full-field macro profile measurement via a X-Y stage. Conducting the measurement with a 20x objective of the Mirau interferometer the lateral resolution is 0.335 μm and the vertical resolution is 8 nm. Dependent on the sampling spacing and scanning depth, the positioning time for a single measurement is usually 0.1~2.5 seconds. The scope for horizontal measurement is defined within the X-Y stage and the vertical scanning range can reach to 20 mm for the adopted Z stage.

並列關鍵字

Microscopic Interferometer ； Transparent Materials ； Profile Measurement ； Auto Focusing ； Centroid Method

參考文獻

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