Laser Sealing of Membrane Vent Holes With Controlled Surface Asperity

The laser pulse is divided into multiple distinct pulses with different characteristics. The first laser pulse has a first set of characteristics (e.g., higher power, longer duration) to melt and seal the vent hole, while the second laser pulse has a second set of characteristics (e.g., lower power, shorter duration) to smooth the surface asperity. This segmentation of the sealing process into distinct phases resolves the contradiction by addressing both seal formation and surface quality with specialized pulses.

The method employs periodic laser pulsing with specific timing and characteristic variations. The sequential application of the first laser pulse followed by the second laser pulse creates a periodic action pattern that first forms the seal and then refines the surface. This periodic approach with controlled intervals allows the material to respond differently to each pulse, achieving both sealing and surface smoothness.

The complex sealing process is segmented into distinct laser pulse phases, each targeting specific physical phenomena. The first pulse addresses melting and initial sealing while the second pulse addresses surface smoothing. This segmentation simplifies the control of complicated physics by breaking down the continuous complex process into manageable discrete steps with controlled parameters.

The method employs systematic parameter changes between laser pulses, including power, duration, and timing characteristics. By carefully controlling these parameters, the complex Marangoni flow and phase changes are managed in a predictable manner. The first pulse parameters are optimized for sealing while the second pulse parameters are optimized for surface quality, resolving the complexity through parameter optimization.