A Note On Subsea Optical Amplifiers

An optical amplifier being lowered in the sea during a cable deployment. They are designed to work at depths as great as 10,000 meters where pressure equals a thousand and one earth atmospheres. Their design lifespan is 25 years and they rarely fail. Almost all subsea cable damage involves the fibre cable itself as opposed to the amplifiers. Besides immense pressure, the amplifiers must resist sea salt corrosion. To do so their hulls are generally comprised of titanium or high strength beryllium copper alloys. Titanium offers an exceptionally high strength to weight ratio as well as unmatched corrosion resistance at ocean depth pressure. Beryrillium copper dissipates heat extremely well. This is essential as the amplifiers contain many lasers and they generate significant heat.

Photo of a Subsea Optical Amplifier Being Lowered Into the Sea


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