The attached doc is a White Paper Draft from 2018. It provides a very good description of the evolution and rationale for the development of the Optical Interposer Platform. The execution towards the end goal of providing a highly integrated platform combining optics with photonics in an efficient and cost effective hybrid packaging technology has become a reality.
https://docs.google.com/document/d/1XMdBK4FuT2lURZrj1nFqWPfXl-ynw5GOOpMOiF5xFZM/edit?usp=sharing