Multicore Fiber (MCF) Test Coupling
When the goal is accurate optical testing of multicore fiber, the cleanest path is the shortest one: couple a well‑characterized source or buffer fiber directly into the specific core you’re measuring. Our test and measurement systems are built around that principle and can be equipped with automated MCF alignment modules—so the numbers you record reflect the fiber under test, not the fixture in front of it.
What you get with PK's MCF coupling:
- Traceable results with a well‑understood uncertainty budget
- Deterministic launch conditions (spot, NA, position) per core
- Highest possible dynamic range for per-core measurements and crosstalk
- Repeatability across cores, fiber geometries and systems
Why direct alignment excels
Measure the fiber—not the fixture.
Direct MCF coupling keeps the test chain simple: instrument → MCF core. Fewer unknowns and less drift mean less variation and less calibration overhead.
Launch control you can set—and prove.
Our precision stages and vision systems place the spot where you intend, at the size and NA you specify.
Cleaner sources and higher dynamic range.
Minimizing interfaces reduces parasitic reflections, improves signal-to-noise ratios and removes the risk of adding unwanted birefringence.
True crosstalk characterization.
Excite one core at a time and any power seen elsewhere comes from the MCF, not the fixture—exactly what you want for inter‑core coupling work.
Throughput without compromise.
Teach‑and‑repeat automation with MCF wizards lets you scan every core quickly while keeping the accuracy benefits of direct coupling.
A fair note on fan‑in/fan‑out (FIFO)
FIFOs are excellent for system I/O and demos. But for fiber testing, they typically add:
- An extra transfer function (loss, polarization effects, internal path differences) to characterize and remove
- Additional interfaces that can raise uncertainty and increase losses and measurement artifacts
- Fixed geometry that can mis‑launch when core spacing, rotational alignment and MFD don’t match
If your product includes a FIFO, keep it in the path as part of the device under test. Otherwise, remove it and test the fiber directly.
The Photon Kinetics approach
- Precision mechanics for unambiguous core mapping and stability
- Machine‑vision alignment to register the core locations and step from core‑to‑core reliably
- Closed‑loop peaking for fast, repeatable coupling
Bottom line: If your priority is confident, comparable results across cores, samples, and time, direct alignment is the most robust method—and it’s exactly what our tools are designed to deliver.
Products ready to directly couple into multicore fiber: