What is The Principle And Use of Fiber Optic Couplers?

As we all know, optical network systems also need to couple, branch, and distribute optical signals, so this requires fiber optic FBT couplers to achieve this. So, what is an fiber optic FBT coupler, and what are the principles and uses of an fiber optic FBT coupler?

Definition of Fiber Optic Couplers

The fiber optic FBT coupler is a device that can couple and redistribute the optical signal in transmission in the coupling zone of the special structure. Fiber optic FBT couplers can be divided into standard couplers, direct-connect couplers, star/tree couplers, and wavelength multiplexers (WDM, if the wavelength is high-density separation, that is, the wavelength spacing is narrow, it belongs to DWDM).

Working Principle of Fiber Optic Couplers

The simplest form of fiber optic FBT coupler consists of two closely spaced parallel single-mode fibers. The basic operation of this structure involves the partial or complete transmission of power between two waveguides. The power exchange is due to the optical coupling between the evanescent tail of one waveguide mode to another waveguide mode, where the light is emitted, the natural mode of the second waveguide. This optical interaction can also be seen as the jump between the symmetry of the composite structure and the antisymmetric super mode. Evenly spaced parallel interaction areas play a key role in the coupling process. The interaction area has a longitudinal invariant structure, and the light coupling in this area can be understood through coupling mode analysis.

Function of Fiber Optic Couplers

1). Network monitoring

2). EDFA components

3). Optical test system

4). Fiber optic sensor