Analysis of sonic waves generated during laser engraving of printed circuits

作者：Gorkic Ales^*; Kovacic Drago; Diaci Janez

来源：International Journal of Advanced Manufacturing Technology, 2009, 42(1-2): 138-144.

DOI：10.1007/s00170-008-1581-7

• Laser engraving
• Direct laser structuring (DLS)
• Printed circuit board (PCB)
• Acoustic detection
• Process monitoring

We present an experiment where sonic waves generated during the laser engraving of printed circuit boards (PCB) were acquired and analyzed. The sonic waves were detected simultaneously using a microphone and a laser beam deflection probe. An efficient windowed peak-to-peak signal processing algorithm was developed to examine the relation between the detected signals and the engraving quality. The results of signal analysis were compared to the engraving surface topography, measured by means of optical microscopy with extended depth-of-field digital photography. The results show that it is possible to distinguish between shallow, good, and burnt engravings by examination of the acquired sonic signals. This observation opens the possibility of automated monitoring or even control of the process of laser engraving PCBs using sonic wave detection.

• 出版日期2009-5