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Fiber Optic Coupler

Fused Fiber Optic Components

G&H manufactures a comprehensive line of fused fiber couplers for visible and NIR wavelengths using single-mode and polarization maintaining fiber; we also offer multimode pump combiners. Our fused fiber components possess low insertion loss and high extinction ratio, and are manufactured to exacting standards for quality and reliability. 

Widely used for branching optical signals and interfacing in telecommunications, sensor, and biomedical systems, our fiber couplers have been selected for deployment in environments requiring rigorous quality and reliability standards such as undersea and space, as well as in OCT systems.

Fused fiber couplers split and combine light signals directly within a fiber medium by coupling between the two fiber cores. When the fiber fusing and tapering process is well executed, it results in low optical loss and high reliability. By varying the parameters of the fusion and tapering process, the proportion of light split between fibers and the wavelength at which the split occurs can be very precisely controlled. Our fused coupler production process has been honed over decades leading to a quality and reliability suitable for carrying telephone and internet signals under the world’s oceans.  

G&H offers a wide range of fiber components that includes wavelength splitters and combiners, as well attenuators, taps, and Wavelength Division Multiplexers (WDMs). The ability to manufacture fiber optic components over a wide range of wavelengths (400-2200 nm) allows us to address many applications in the biomedical, aerospace and telecommunication sectors. We also offer devices to meet the needs of optical coherence tomography (OCT) based systems, and components for operation over a broad band at center wavelengths of up to 2 µm. 

SM components

G&H single-mode couplers are used to achieve accurate monitoring and splitting of optical signals from 1% to 50%. Based on our fused fiber technology, the SM coupler line demonstrates very low loss and high power handling.

PM components


We offer polarization-maintaining (PM) couplers in coupling ratios from 1% to 50%, manufactured using industry standard polarization maintaining fiber. The center operating wavelength may be chosen from within a wide variety of operating passbands, including visible (400 nm–700 nm), 780 nm, 820 nm, 980 nm, 1064 nm, 1310 nm, 14xx nm, 15xx nm, 16xx nm, 19xx nm and 21xx nm. PM couplers are available in slow axis, fast axis and axis-independent variants. With extensive expertise in the applications of fiber components, our technical staff can advise on which option is most appropriate for a given application. G&H’s PM couplers operate over a -55°C to +85°C temperature window, making them suitable for applications in harsh environments.

High power multi-mode pump combiners

Our range of multimode combiners for pumping high power fiber lasers is based on precise fusion of multimode fibers techniques. For pumping of complex fiber amplifier designs, we have developed a signal feedthrough fiber at the center of the multimode fiber bundle, which is both single mode and polarization maintaining. We manufacture Nx1 multimode combiners as well as N+1x1 combiners with a signal feedthrough fiber. Standard components are 3x1, 7x1, 2+1x1 and 6+1x1. All variants are available with custom pump, signal and output fibers.  

Applications of fused fiber optic components

Avionic and space communications, biomedical instrumentation, fiber laser systems, industrial micromachining, interferometry, LIDAR, medical diagnostics, optical coherence tomography (OCT), sensing, telecommunications.

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