"our friends at IBM" was said in an ASM years ago and IBM has certainly been a long-term NDA of LWLG's, IBM already is big on the use of passive polymer components, and IBM is also part of Polariton, they even share the same building
Xena, I don't have the credentials to answer that, wish I did. Here's another IBM link FWIW.
Table 1. Stringent requirements for MM PWGs used as optical interconnects. This illustrates why silicones are excellent base materials to realize optical PCBs. Within a close collaboration with our polymer materials provider Dow Corning Corporation, we were able to identify suitable silicone-based optical polymers and tailor them to fulfill all requirements.