Passive fiber-optic components are vital ingredients in future space photonic sub-systems responsible for the generation, amplification and transmission of light for telecom and sensing applications. An integral part of HIPPO project is to design and develop key components including fused pump combiners and high power handing optical isolators.


Work on fused pump combiners focused on two specific devices.


2x1 pump combiner for reduced cladding photonic crystal fibers to investigate coupling to 60um cladding. The fiber was provided by FiberWare and G&H developed the pigtailed component. The single-mode performance was 94% transmission, measured outside the absorption range, i.e. @1310nm and the multimode performance was 92.5%, measured outside the absorption range, i.e. @1100nm.



7x1 pump combiners to be used for optical pumping of high-power fiber amplifiers were fabricated. The number of ports allows for the design and development of high-power amplifiers for LEO-GEO and GEO to ground applications.


SM coupling efficiency Path 1 Path 2 Path 3 Path 4 Path 5 Path 6
90.74% 95.69% 95.56% 95.26% 94.87% 96.00% 95.81%



Work on optical isolators focused on:

  • Optical design of a beam-expanded optical isolator for high-power handing
  • Design and development of the mechanical design for housing the high-power isolator

The measured isolation between 1540 – 1565 nm was >30 dB with a peak isolation of 41.5 dB. The insertion loss was between 0.52 dB and 0.57 dB.