I'm very fortunate to have access to a laser engraver. The pocketing you see was the first phase of the engraving process. In the first phase, the laser rasters back and forth over the work and engraves any of your artwork onto the piece. In that mode, it's a lot like an inkjet printer and it can get up to 1200 dpi, so you can get pretty fancy if you want. In my case, I just went with a solid fill inside the gear which resulted in the pocket you see. Once it's done the engraving operation, it switches to vector mode and starts cutting.
I've also been playing with another engraving mode they call 3D mode. This mode works with grayscale fills to achieve a form of relief carving. It's tricky, but I think I have it dialed in. I have another gear project in mind that will utilize that mode. I'll post some pictures when I have something to show.