GLSUN's free space isolator, in-line optical isolator, and high power optical isolator are passive components that allow the transmission of laser beams emitted from a laser diode to travel in only one direction. GLSUN optical isolators are typically used to prevent unwanted feedback into an optical oscillator.

GLSUN fiber optic circulator is a non-reciprocal device that redirect light from port-to-port sequentially in only one direction. Optical circulator is a three-port or four-port optical device designed such that light entering any port exits from the next. These optical circulators and PM circulators can be widely used in Dispersion Compensation Modules (DCMs), Optical Add-Drop Multiplexers (OADMs), optical amplifiers, CATV Optical Fiber Link and Wavelength Add/Drop applications.

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