Planar Lightwave Circuit (PLC) utilizes semiconductor processes such as photolithography, etching, and deposition to create optical paths on substrates, enabling the propagation of optical signals. A typical optical waveguide structure consists of three parts: a high-refractive-index core, a. The devices are based on planar optical waveguides, in which light is confined to substrate-surface channels and routed onto the chip. These channels are typically less than 10 microns across and are patterned using microlithography techniques. This paper reviews the recent progress and future prospects of PLC technologies including arrayed-waveguide grating multiplexers, optical add/drop multiplexers, programmable. The EM4 high reliability, high grade and superior performance planar lightwave circuits (PLC) based planar waveguide optical signal splitters are the component of choice to combine or split optical power in optical fiber networks and systems. EM4 manufactures PLC components. phasis on the transmission theory.
