What is Core Pitch?

Core Pitch refers to the center-to-center distance between adjacent fiber cores within a Fiber Array (FA). In Silicon Photonics and CPO architectures, it is a fundamental parameter that defines interconnect density. Since chip-level waveguides are packed extremely tight, the Core Pitch of the FA must achieve sub-micron matching with the waveguide spacing to ensure efficient optical signal coupling. 

Standard Specifications & Trends 

1. Standard Pitch: 

• 250μm: Commonly used in general-purpose transceiver modules. 

• 127μm: The industry standard for CPO and Silicon Photonics, optimized for compact form factors and higher channel counts. 

2.Narrow Pitch: 

To maximize Beachfront Density in next-gen CPO modules, Core Pitch is evolving toward 80μm. This often requires Reduced Cladding Fibers or advanced etching techniques. 

The Importance of Precision 

In High-Performance Computing (HPC), Core Pitch accuracy is a direct determinant of Insertion Loss (IL). Utilizing high-precision V-Groove substrates, the pitch error must be controlled within +/-0.5μm. Any significant accumulated error across high-count channels will prevent simultaneous alignment, leading to signal degradation and compromising the overall stability of the optical interconnect.