PCB雷射鑽孔電流計掃描器與X-Y床台路徑

以雷射加工PCB盲導孔優於機械式鑽孔方式，不但容易設加工深度，其形成的錐度也適合後續的電鍍作業。雷射PCB鑽盲孔作業需大量定位及加工步驟(跳躍及發射)的雷射掃描系統，通常要以電流計掃描器進行快速掃描另輔以X-Y床台進行大範圍的定位。雷射PCB鑽盲孔點數至少在數萬點以上，電流計掃描器與X-Y床台兩者之間的配合對提升加工速度甚至加工品質很重要。本計畫建議讓電流計掃描器依最短路徑原則掃描，X-Y床台則以往復方式掃描，X-Y床台移動步階大小可以變動。本研究依此原則編寫鑽孔路徑最佳化程式，以便提升鑽孔作業速度並保持加工品質。 PCB板常含有IC接點孔相當密集，這些點應避免使用床台的移動定位以避免產生誤差。本文便是利用參數margin來定義電流計掃描器的預留量。本文顯示兩種測試結果，一是常見的PCB佈局，另一是有相同點數密度但鑽孔點為隨機分布。測試結果顯示本文所示方法較適用於PCB佈置。

關鍵字

盲導孔；電流計掃描器；鑽孔路徑最佳化

並列摘要

Laser drilling for PCB blind via processing is better than mechanical drilling in terms of depth control and the proper cross section for electroplating. PCB drilling needs to process a large number of jump and positioning and are often conducted with galvanometer scanners system which is suitable fast positioning and an X-Y table which is responsible for a large area scanning. Coordination of galvanometer scanner and X-Y table is important for improving processing speed and quality. The optimization strategy used in the current work is shortest path for galvanometer scanners and back-and-forth scanning route for the X-Y tables. PCB often contain high-density hole for ICs. For better quality operations, it should be avoid movement of X-Y table while processing those areas. A parameter, margin, is used to define the allowance of galvanometer scanning area. Two test results are shown. First is the normal PCB layout and the second if random distribution with the same point/area ratio. The strategy used in work is more suitable for the former case. Key words: blind via, galvanometer scanners, optimization.