Phil-v: Optical engine: Is that referring to the VCSEL or the IR detector for a possible NRE?

There's no clear definition of the term Optical Engine. It is used differently by different companies.

I suggest the POET Optical Engine is the integrated VCSEL transceiver, i.e. VCSEL + detector + electronics. However, this is now on my list of questions to the POET management. They should consistently use the same name for the same thing and clearly define what that thing is.