軟性印刷電路板(FPCBs)主要功能是將各種電子零組件，提供置放及連結的功能，是由聚亞醯胺(PI)或聚酯(PET)軟性材料為基材所組成的電路板，軟性印刷電路板發展趨勢為可撓性、輕量化、減少擺放空間，由於這些特性，使得軟性電路板產量增加，如此一來微影曝光製程成為軟性印刷電路板產量的主要因素之一，而近期發展數位微鏡裝置(DMD)的微影曝光系統擁有快速印刷圖案的能力，且更具自動化的潛能，然而目前研究自動光學檢測在印刷電路板上微影曝光後線路的檢測探討居多，本論文主要基礎建立在無微影光罩曝光系統，由於軟性基材在機台環境溫度的不同會造成彎曲曲率不規則變化，利用數位微鏡裝置投影出方格線，來使相機擷取影像，透過模板匹配法、遮罩化運算、邊緣點檢測和扭曲校正法來找出軟性印刷電路板上變形量的演算法，將原始欲定義曝光之電路圖重新校準並符合軟性印刷電路板之基材的形變量，利用影像視覺對位法對於軟性基材做校準計算，計算結果並回授到PC-BASED控制P.I.D.控制線性馬達伺服模組進行平面之靜態檢測。光機電自動化系統對於不同的校正符號探討，研究系統整合如何更快速且精確之檢測在一片250×250 mm2，本研究利用兩種定位符號以及三種不同尺寸大小之可視範圍進行測試，總共六種樣品進行靜態檢測，最後，在方格線檢測區域大小為50×40 mm2所耗費平均檢測時間最快為每一列8.38秒，小於一般的檢測時間每一列19.2秒，此時相機模組之最小解析度為17.51 μm。

Flexible printed circuit boards (FPCBs) are made of flexible materials such as polyimide and polyester. They can be bent, folded, rolled stretched and “moved freely” within a 3-D space. Owing to these characteristics, FPCBs are often used as the substrate to carry electrical components the conduction lines and it turns out enabling the lithography process is critical to the FPCB production. Recently, many groups investigate the lithography process using a DMD-based technique due to its capability to print the lithography patterns at the high speed. However, these studies only focused on rigid substrates and performed automated optical inspection (AOI) the patterns after completing the lithography process. The effect of flexible surface on the exposure field has rarely been investigated. Bent surfaces may reduce the accuracy and the performance of lithography process to print the desired pattern. In this research, a flexible bending surface detection (FBSD) algorithm is proposed for the maskless lithography system with DMD devices. Our idea is to use projected grid linear lines on flexible substrates for the exposure field distortion correction using the DMD devices. The calibration procedure starts with the template matching, region of interest, line measurement and calibrated method to acquire the distorted image information. In order to verify the designed correction scheme, a flexible PCB film with the area 250×250 mm2 is placed on a scanning stage with a single axis linear controllable motor through the PID controller for the test of the spending time in the detection and correction. With the use of the projected grid field sizes 50×40 mm2, the proposed FBSD algorithm showed that the minimum resolution is 17.5 μm. In addition, the algorithm spends only 8.38 seconds per array to completely recognize the target, in which it is much shorter than the typical recognition time 19.2 seconds per array.

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