Its primary function is to route data carried by light without converting the signal into an electrical form for processing, defining it as a true “all-optical” switch. They're a core component in fiber-optic networks, where data travels as pulses of light through glass fibers. This technology allows for high bit rate transmission to be switched between various optical lines. Light occurring on an optical transistor's input changes the intensity of light emitted from the transistor's output while output power is supplied by an. Optical switching represents a fundamental technological evolution, shifting data routing from the domain of electrons to the realm of photons, or light.