An optocoupler is a device used to convert optical signals to electrical signals or electrical signals to optical signals in an optical communication system. It works on the principle of optical coupling.
The optocoupler consists of two optical fibers, usually an input fiber and an output fiber. In an optocoupler, there is optical coupling between the two fibers, resulting in a portion of the optical signal being transmitted from the input fiber to the output fiber. Inside the optocoupler, the optical signal is converted from the core of the input fiber to an electrical signal at the core of the output fiber, which is then converted back to an optical signal from the core of the output fiber.
The principle of operation of an optocoupler is based on the physical properties of glass or other media, such as their refractive index and optical conductivity. When an optical signal passes from an input fiber into an optocoupler, the light within the fiber is coupled, which results in a portion of the light being transferred to the output fiber. Thus, the optocoupler enables the conversion of optical signals to electrical signals, which in turn enables the transmission of high-speed data.