According to the principle, optical splitter can be divided into two types: melting tapered and planar waveguide.
Melt-tapered products are made by welding two or more fibers sideways;the planar waveguide type is a micro-optical element type product that adopts a photolithography technique to form an optical waveguide on a dielectric or a semiconductor substrate to realize a branch distribution function.
The spectroscopic principles of these two types are similar. They can achieve different branching quantities by changing the evanescent field mutual coupling (coupling degree, coupling length) between fibers and changing the fiber fiber radius. On the contrary, they can combine multiple optical signals into one signal, which is called a synthesizer. Because of its simple manufacturing method, low price, easy connection with external optical fiber, and its advantages such as mechanical vibration and temperature change, fused-cone-shaped optical fiber coupler becomes a mainstream manufacturing technology in the market now.