Issue link: https://iconnect007.uberflip.com/i/808383
44 The PCB Magazine • April 2017 by I-Connect007 Are embedded optics on PCBs set to make a breakthrough in the upcoming years? Ac- cording to Dr. Craig Davidson, VP of Corporate Technology at TTM, it might be closer than you'd expect. In a recent interview with the I-Connect007 team, Craig outlines TTM's cur- rent pursuit of high-volume manufacturing lines able to deliver embedded optical intercon- nect, what that would mean for the PCB indus- try, and why he thinks there will be manufac- turing production capability by 2020. Barry Matties: Craig, for context, tell us a little bit about the optical side of TTM and what you guys are doing there. Craig Davidson: Sure. We're engaged already with the optical groups of many large custom- ers. As you probably know, there are optical products today that do not include onboard optical interconnect or inboard optical inter- connect, but rather optical cables to the edge of the board. These include fiber connectors and transceivers embedded in connectors. TTM certainly supports networking companies with these kinds of products formally classified as optical. What we're really taking about here is the future as we bring optical signals on board, onto the printed circuit board directly embedded in the board for optical packages, line cards or backplanes. Matties: Yes. Davidson: The basic capability has been around for decades. I first got involved in it back in the year 2000 when there was a big push for on- board optical interconnect and just about every printed circuit board fabricator at the time was doing something around embedding fibers into boards. Many PCB fabricators have these kinds of processes. It's relatively simple to do but it's not a very happy solution. You still have problems with 90° bends, for example, and the z-axis in the board, and you certainly have continuing difficulties associated with connectorizing the fibers. Also, importantly, is registration—making sure the fibers actually end up where they need to be. That›s a very difficult task. So those types of problems haven›t really been solved for TTM Shines a Light on Optical Interconnect FEATURE CONVERSATION Figure 1: Low loss 1.4m-long waveguide. (Source: Optical Inter- connects—Phase I Final Report. Date: 2016-06-01 Rev 1. : HDP User Group International, Inc., Document HDP20161R).