Optical fiber assemblies resistant to radiations

Thanks to its know-how and expertise in complex and extreme environments, SEDI-ATI Fibres Optiques offer solutions based on optical fibers that are withstanding rays and radiations up to 1 GGy.

optical fiber assemblies in ray and radiation environments

Resistance to rays and radiations

Optical fibers allow transmission equipment to be moved from radiating or ionising environments, reducing the risk to operators. There are special optical fibers that are resistant to radiation and others that are resistant to solarisation. An optical fiber is intrinsically insensitive to electro-magnetic interference (EMI) and, properly protected against radiation, it can easily be used in nuclear power stations or medical facilities such as MRIs and scanners.

The problem

When exposed to radiation, the optical fiber can be degraded resulting in increased optical attenuation (decrease in optical signal intensity along the fiber), reduced optical power at the fiber output, or effects on bandwidth (change in the optical characteristics of the fiber resulting in changes in the spectral properties of optical signals). Radiation also affect on the optical fiber assembly, notably degrading components (connectors, insulators, modulators…) or damaging the coating. At low wavelengths (below 250 nm), UV radiation degrades signal transmission in standard silica fibers, leading to solarisation (increased light absorption in the UV range, which can invalidate measurements).


We select the most suitable fibers for your applications. To date, our optical fiber assemblies are resistant to radiation of up to 1 GGy and solarisation (UV radiation) of up to 200 nm. Their metallic coating makes them immune to radiation. Sealings and other materials are choosen according to your final application and constraints. We can design different types of radiation-resistant fiber assemblies, and almost all our ranges are suitable for this purpose (hermetic feedthroughs, couplers, multiplexersbundles, medical probes, special fiber optic cables and patchcords, etc).

In addition, SEDI-ATI has teamed up with leading optical fiber manufacturers to co-develop special< preforms to produce unique metal-coated single-mode and multimode optical fibers for use in the nuclear environment! The 3F2E project is 100% French and will enable us to offer radiation-resistant (rad-hard) SM and MM optical fibers while promoting Made In France.

Case studies

Inspect: online and remote dosimetry for inspecting nuclear equipment

SEDI-ATI took part in the INSPECT project by supplying a bundle of 16-channel optical fibers for instrumentation to measure the level of radioactivity in nuclear equipments.

Scintillating fiber dosimeter for radiology

SEDI-ATI designs scintillating fiber optic probes for dosimeter applications applied to radiology.

Optical measurement of the water level in nuclear reactor pools

SEDI-ATI offers nuclearized fiber-optic sensors that perform optical time-of-flight measurement of the water level of nuclear reactor pools.

Fiber-optic probes at the heart of the Jules Horowitz Reactor

SEDI-ATI has designed custom-made fiber-optic probes to be placed at multiple locations inside the Jules Horowitz Reactor.

Don’t hesitate to contact us with your requirements