The optocoupler consists of a light source and a receiver. The light source and receiver are assembled in the same closed housing and isolated from each other by a transparent insulator. The pins of the light source are the input end and the pins of the receiver are the output end. The common light source is a light emitting diode and the receiver is a photodiode, phototransistor, etc.
The role of fiber coupler is to achieve the splicing/combination of optical signals, or to extend the components of fiber optic link. It can be used in the field of optical passive devices, in telecommunications networks, cable TV networks, subscriber loop systems, and local networks.
It can be used to:
A. Transform optical signals into electrical signals;
B. Coupling multi-mode signals into single-mode signals;
C. Connect the cross-section of two fiber optic connectors through fiber optic holes;
D. Connect two sets of optical signals to each other.
Technical specifications of fiber optic coupler:
Insertion loss, additional loss, spectral ratio and isolation. In addition, there are uniformity, return loss, directivity, and PDL.