So just to be clear my working life was associated with Power Systems Operations. Co-ordinating/directing the operations (for Ontario) of the North American Bulk Power Grid the biggest machine on the planet and very complex. Part of that involved understanding a variety of communication systems and a lot of other stuff for protection and control and the operation of the bulk power grid.

PLC = Planar Lightwave Circuit

PLC for me in my working life was associated "Power Line Carrier" communications and one of the earliest forms of end to end communications for high voltage lines. The signal was applied directly to the blue phase of the powerline at operating voltages up to 230,000 volts. It required some heavy duty equipment. Big wavetraps tuned to the resonant frequency of the communication signal. It was prone to failure during high ambient conditions due to coupling capacitor canister failure but one of the really bad things is when a blue phase ground fault occurred communication for that faulted line was lost and backup protections which are time delayed were required to clear the faults locally and that slow operation to clear the fault would rock system stability. And if you lived in California it would start fires.

PLC later became an acronym for "Programmable Logic Controller". Which became a big part of our redundant protection schemes to detect and initiate fault clearance of bulk power equipment elements.      

I was pretty obsessive throughout my working life with finding technical and procedural problems and finding solutions to those problems. This resulted in my move up through the chain of authority and being selected as the go to guy to find solutions. Appears I  still have that drive which often wakes me up in the wee hours of the morning to post.   

I wanted to share this because there are some that no doubt think I am acting as a plant and just parroting what I am told. Nothing could be further from the truth. I ask question based on a lot of reading and a lot of trying to find answers for myself. And when my understanding becomes acknowledged and recognized as having merit I share that understanding. I can’t help myself as it is the way I am wired.

Anyway I felt it was important to share this.

All of the documentation that I have read from this company on what they are now building agrees with all the independent research/reading I have done. It is very much a learning process for me. It is really not a well-known subject for very many people.

I have more to share which validates everything I have come to learn about this platform and why it is a breakthrough. But to start take a look at the following link.

https://www.sciencedirect.com/topics/engineering/optical-coupler

coupling loss depends on modal shape mismatch between the fiber and waveguide.

That can also be applied to connections between the optical die and the waveguide edge couplings.

And then check out Suresh’s 2018 presentation for CIOE.

And when you look at references to silica waveguides (in the link above) which are glass and make  great waveguides I guess one of the biggest limitations is you can’t build and optical interposer out of it the way Suresh has with the dielectric. Melting point is about 1000’C.   You need low stress low temperature deposition around 300’C onto the silicon wafer which is the temperature POET uses to deposit the dielectric layers onto the silicon wafer to  produce the waveguides. So no pathway to the use silica in a CMOS flow (which is also  highlighted in Suresh’s presentation).

 Slide 16 of 30 that Suresh presented last Sept at CIOE. Note that the shape of the light (mode) that becomes matched from the spot side converters (in this case for the fiber) both into and out of the arrayed waveguide. I expect that Suresh’s presentation gained a lot of  industry attention that led us to where we are now.

https://poet-technologies.com/docs/presentations/POET%20CIOE%20Presentation_Sept_2018_FINAL.pdf    

Too bad the  market failed to recognize it but it  think  it will!