Fiber Coupling Efficiency Simulator
Simulate laser diode-to-fiber coupling in real time. Adjust Fast & Slow Axis Divergence, Lens Focal Length, and Fiber NA & Core Diameter to calculate mode overlap, NA mismatch loss, and total coupling efficiency.
Interactive optics labFiber Coupling Efficiency
Start here
1Choose a complete example.
2Match the spot to the fiber core.
3Check which loss limits coupling.
Conceptual view · dimensions not to scale
Estimated coupling—
Insertion loss—
FA spot diameter—
SA spot diameter—
Total coupling efficiency
—
Start with an example system
Educational starting points—not component specifications1 · Laser source
Fast Axis and Slow Axis describe the source’s two different divergence directions.
405 nm2000 nm
5°60°
2°30°
Ideal 1.0Poor 5.0
2 · Coupling lens
The lens must collect the source cone and focus it onto the fiber face.
1 mm20 mm
0.100.90
3 · Receiving fiber
Core size controls spatial capture; fiber NA controls angular acceptance.
2 µm600 µm
0.050.65
Lens collection—
Spatial overlap—
NA acceptance—
What this means: Adjust a parameter to see the limiting loss.
Ideal centered alignment · estimated lens transmission 92%·
η ≈ lens collection × overlap × NA acceptance × 0.92API Access & Educational Use
This Fiber Coupling Efficiency Simulator is available for integration into university photonics courses,
laser engineering training platforms, and industrial simulation tools via API. Contact our team at
contact@ephotonics.com for custom fiber presets,
multi-lens system simulations, and white-label deployments for academic or industrial use.Interactive optics labFiber Coupling Efficiency
Start here
1Choose a complete example.
2Match the spot to the fiber core.
3Check which loss limits coupling.
Conceptual view · dimensions not to scale
Estimated coupling—
Insertion loss—
FA spot diameter—
SA spot diameter—
Total coupling efficiency
—
Start with an example system
Educational starting points—not component specifications1 · Laser diode source
FA and SA are the diode’s two different divergence directions.
405 nm2000 nm
5°60°
2°30°
Ideal 1.0Poor 5.0
2 · Coupling lens
The lens must collect the diode cone and focus it onto the fiber face.
1 mm20 mm
0.100.90
3 · Receiving fiber
Core size controls spatial capture; fiber NA controls angular acceptance.
2 µm600 µm
0.050.65
Lens collection—
Spatial overlap—
NA acceptance—
What this means: Adjust a parameter to see the limiting loss.
Ideal centered alignment · estimated lens transmission 92%·
η ≈ lens collection × overlap × NA acceptance × 0.92