Photonic Sourcing

Sabeus Precision Advantage Gain Flattening Filters (GFFs) are ultra-precise long-period grating (LPG) filters based on Sabeus’ wavelength selectivity technology. Designed for EDFA and Raman amplifiers, Sabeus’ GFFs are the ideal solution for control of non-uniform gain across optical channels of differing wavelengths.

Sabeus' long-period fiber grating (LPFG) based GFFs can be custom designed to provide spectrally selective loss by coupling light from a guided mode into forward propagating cladding modes where it is lost due to absorption and scattering. The coupling from the guided mode to the cladding modes is wavelength dependent providing spectrally selective loss. The LPFG is an intrinsic optical fiber structure with optical properties periodically varying along the fiber, such that the conditions for the interaction of several copropagating modes are satisfied. In contrast to fiber Bragg gratings (FBGs), LPFGs couple copropagating modes with close propagation constants; therefore, the period of such a grating can considerably exceed the wavelength of radiation propagating in the fiber.

Sabeus’ highly customizable GFFs are manufactured to meet even the most challenging spectral profile.

• Customizable Spectral Response
• Low Error Function From Target Filter Spectrum
• Low Insertion Loss
• Low Chromatic Dispersion
• No Isolator Required (reduces overall system cost)
• Bit Rate Independent
• Rapid Turnaround on Prototypes and Production (to ISO9000/Telecordia standards)
• All fiber-based optical athermally packaged component

• Suppression of C- and L- band wavelengths in Erbium-Doped Fiber Amplifiers (EDFAs)
• Filters to remove unwanted wavelengths from fiber core
• Suppression of wavelengths for Yb-doped and Er lasers
• Cladding mode pump laser light propagation
• Clean up filters
• Correct gain spectrum distortion for EDFA and Raman amplifiers
• Correct for wavelength dependent loss in single mode fibers