Abstract: In one embodiment, a surface has a laser-beam machined area including an array of micro-sized conical pillars that are arranged in orthogonal rows and columns across the surface and that extend upward, the conical pillars defining deep troughs between them that are configured to absorb electrons, electromagnetic radiation, or both, the conical pillars tapering from relatively wide bases to pointed tips, the conical pillars comprising outer surfaces that are covered with a plurality of nanoparticles.

Abstract: In one embodiment, a surface has a laser-beam machined area including an array of micro-sized conical pillars that are arranged in orthogonal rows and columns across the surface and that extend upward, the conical pillars defining deep troughs between them that are configured to absorb electrons, electromagnetic radiation, or both, the conical pillars tapering from relatively wide bases to pointed tips, the conical pillars comprising outer surfaces that are covered with a plurality of nanoparticles.

Abstract: A pulsed eddy current (PEC) instrument acquires PEC pulse responses from different locations on a structure being inspected. The difference between the acquired PEC pulse responses and a reference PEC response is determined to obtain time-domain difference signals having a time value and a magnitude value. The time and magnitude values are stored in memory with location information. An image display is provided that is determined from the stored magnitude values, although magnitude values for difference signals whose time values do not meet a defined time condition are filtered from the display. The time condition filters from the display known conditions such as the presence of fasteners, the presence of air-gaps between layers of the structure, and excessive PEC probe lift-off from the structure and filters the display so that only information from a particular layer or depth of the inspected structure is displayed.