顯微鏡低成本自動對焦平台模組設計

Module design of a low cost auto-focusing platform for microscopes

黃智成(Huang-Chih Cheng)

指導教授 ： 章明

中原大學/工學院/機械工程研究所/碩士(2012年)

https://doi.org/10.6840/cycu201200021

摘要

市面上一般顯微鏡設備對焦部分通常都需要使用手動調整，使得顯微鏡在使用上增添許多不方便，也讓顯微鏡的應用受到限制；為解決顯微鏡自動對焦的問題，本研究開發出一套可與市售一般顯微鏡整合的自動對焦追蹤平台系統，可以減少人為操作所產生的誤差，及縮短對焦調整與尋找待測物的時間。
平台系統主架構利用馬達與滾珠螺桿作為移動機構，設計出可用於顯微鏡上的三軸定位平台，設計時運用 Solidworks的COSMOS對結構進行靜態分析，分析受外力時機構元件的變形量，並找出容許變形量 1µm以下的元件尺寸。組裝完成後透過雷射干涉儀進行系統校準與誤差補償，補償後平台的反覆定位精度可達 ±2µm，XY軸移動真直度可達 5µm。
本系統的自動對焦追蹤模組是以改變物距的方式，也就是控制Z軸馬達驅動螺桿移動平台改變高度位置，再與清晰度演算法配合以達到自動對焦的目標。將平台模組與自動對焦模組整合後，本研究所開發完成的定位平台系統，已可提供研究人員更快速且有效率的找到最佳的對焦位置，應付龐大的樣本檢測與觀察的需要。

關鍵字

自動對焦

並列摘要

The focusing part of microscopes on the market has to be adjusted manually, this causes inconveniences while using. Moreover, it limits diversifying applications of microscope. In order to figure this problem out, an auto-focusing stage that combines with ordinary microscopes was developed. This research reduces human error and increases the efficiency of finding object.
Moving mechanism of XYZ positioning stage was consisted of motor and ball screw. In this research applies static analysis, which analyzes the deformation of mechanical parts that caused by external forces, and defines the allowable tolerance within 1um by COSMOS. In addition, corrects the error by Laser Interferometer, after that, Repeated Positioning Accuracy is able to reach 2um and Straightness of XY axis get to 5um
The technique of Auto-focusing trace is that triggering moving mechanism by means of operating Z axis motor, besides using Sharpness Algorithm. To sum up, the XYZ positioning system that comprises stage and auto-focusing module successfully meets researchers’ needs, which is easier and faster to focus on the object.

並列關鍵字

Auto-focusing

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