Cladding power strippers are an important component in various high-power fiber optic systems. They work by removing excess light from the cladding layer of an optical fiber. In this blog, you will learn what exactly cladding power strippers do and where they are used.

What is a Cladding Power Stripper?

Optical fibers have a core, cladding, and protective outer coating. The core transmits the main light signal. The cladding layer surrounding the core helps confine and guide the light.

In some cases, excess stray light can build up in the cladding. This needs to be removed to avoid interference with the main signal in the core. A cladding power stripper absorbs and strips away this excess cladding light. Effective cladding stripping is essential for optimum performance of fiber optic systems.

Key Uses of Cladding Power Strippers

There are several common uses for cladding power strippers:

Removing Cladding Modes in Single-Mode Fibers

Single-mode fibers are designed to transmit only one mode of light in the core. However, some unwanted cladding modes can occur. A coating around the cladding with a slightly higher refractive index draws these away and dissipates the light. This helps maintain beam quality.

Protecting Signal Sources in Fiber Amplifiers

In high-power fiber amplifiers, residual pump light can reach the signal source end. A cladding stripper removes this to protect the source from excess light. This avoids potential damage to sensitive components.

Removing Excess Pump Light in Double-Clad Fibers

Double-clad fibers have an inner cladding that carries pump light to amplify the signal in the core. Any excess pump light needs to be stripped from the inner cladding. This improves amplifier efficiency.

Protecting Polymer Coatings in Double-Clad Fibers

Outer cladding light in double-clad fibers can damage the polymer coating. A cladding stripper that removes outer cladding light while leaving the inner cladding intact prevents this. This improves fiber reliability.

How Do Cladding Power Strippers Work?

There are a few common techniques used in cladding power strippers:

  • Absorptive coatings – A coating with index higher than the cladding absorbs cladding light.
  • Scatterers – Microscopic irregularities scatter cladding light out of the fiber.
  • Bends and coils – Tight bends in the fiber radiate out cladding light.
  • Narrowed cladding – Etching away cladding thickness forces light out.

High-Power Handling Cladding Power Stripper Designs

In high-power systems, cladding strippers must handle large optical powers. Key design aspects include:

  • Making the stripper long enough to dissipate heat over a large area
  • Optimizing heat sinking and cooling
  • Using materials that can withstand high thermal load
  • Isolating the stripper to avoid damaging nearby components
  • Proper thermal management is critical for reliable operation.

Cladding power strippers play an important role in many fiber optic systems. Understanding their working principles and applications helps optical engineers utilize them most effectively. With robust designs, they can safely remove excess cladding light even in high-power systems.