在使用無光罩曝光機進行印刷電路板的曝光時，需要輸入bmp圖檔來控制DMD鏡面的旋轉狀態，圖檔的每個pixel值會控制一個對應的DMD鏡面，因此需要一個系統能夠即時將輸入的Gerber檔轉換為bmp圖檔來控制DMD。但無光罩曝光機的記憶體有限，無法將完整的Gerber檔轉換為bmp圖檔後直接控制DMD鏡面，需要將整張bmp圖檔切割成小張的bmp圖檔，此步驟原本需要以人工切圖的方式進行，較費時且無法自動化完成，因此本文以Gerber檔解碼及向量圖形裁切法為基礎，開發一系統可將Gerber檔轉換為一向量形式的中間檔，再將中間檔透過slide window(ROI)切割成適當大小的bmp圖檔來輸出，達到即時控制所有DMD鏡面的效果，減少人力耗費的時間以及記憶體使用量，進而實現自動化的功能。

When using a maskless lithography system for the exposure of printed circuit boards, users have to enter a bitmap image file to control the rotation state of the DMD. Each pixel value of the image file controls a corresponding DMD. Therefore, a system is needed to convert the input Gerber file to a bitmap image file to control the DMD in real time. However, the memory of the maskless lithography system is limited, and it is not possible to directly control the DMD after converting a complete Gerber file to a bitmap image file. The entire bitmap image file needs to be cut into small bitmap image files. This step originally required manual cutting which is time-consuming and cannot be completed automatically. Therefore, based on the Gerber file decoding and vector graphics clipping method, this paper develops a system that can convert the Gerber file into a vector form intermediate file, and then cut the intermediate file into a bmp image file of appropriate size through the slide window (ROI) to output. In this way, we can achieve the effect of controlling DMD in real time, reduce the time and labor consumption of manpower, and then realize automation.

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