he optical roadmap has already moved beyond 1.6T.
At ECOC 2026, Coherent is demonstrating a 3.2T transceiver and a 6.4T Near-Packaged Optics engine for next-generation AI networks.
It is also showing technology aimed at 400G-per-lane optical connectivity.
That sounds like an optics story.
But there is an important PCB lesson behind it.
As bandwidth increases, the industry is moving the optical engine closer to the ASIC because long electrical channels become increasingly difficult to manage.
So the electrical PCB path gets shorter.
But shorter does not mean irrelevant.
The remaining channel still depends on:
• Insertion loss
• Dk/Df stability
• Copper roughness
• Controlled impedance
• Via transitions
• Package and module launches
• Power integrity
It also creates an interesting sourcing question:
Do you really need the highest-grade laminate everywhere on the board?
Maybe.
Maybe not.
The right answer depends on the actual channel length, data rate, stack-up and manufacturing process.
At ShinePCB, we prefer to start with those requirements and then match the CCL and PCB process to the application.

Originally published on ShinePCB’s LinkedIn company page: 2026-09-21.