Passive optical components are devices that perform their function without requiring external power or active control. They are the fundamental pipes of a PIC, responsible for manipulating the flow of light through processes such as guiding, splitting, combining, filtering, and. Optical passive components are the quiet workhorses in fiber systems. They don't add gain or require power, but they decide how efficiently, cleanly, and safely light moves through your network or laser chain. They operate solely through inherent optical and physical properties such as geometry. A photonic integrated circuit is a microchip that contains two or more photonic components to form a functioning circuit, manipulating light on a semiconductor substrate. These components help guide, filter, or attenuate light signals, ensuring the efficient transmission of. Pump combiner is built based on fused biconical taper (FBT) technique, widely used in fiber laser,can be designed to meet a wide range of power handling configurations, number of input fibers and adaptation to different fiber types. A series of small-sized TGG isolators and circulators A.