The U.S. Patent and Trademark Office in Alexandria, Va., recently hosted a fascinating display of technology. 3D Systems (NYSE:DDD), Stratasys (NASDAQ:SSYS), and other top companies involved in additive manufacturing, or 3-D printing, displayed their wares in the same room.

Fool analyst Rex Moore was at the conference and chatted with Stratasys engineer Jim Comb. In this installment of our multipart series, Jim talks about the current state of the industry, and why the technology has entered the mainstream.

Rex Moore has no position in any stocks mentioned. The Motley Fool recommends and owns shares of 3D Systems and Stratasys and has options on 3D Systems. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.