From Pontis website:

In complex testing environments it is often needed that electrical signals have to be transmitted into the chamber or out of the chamber to the test equipment.

For that purpose we offer a variety of different interfaces that convert electrical signals into optical signals and back. Such the signal can be transmitted via fibre optics and is immune against electrical fields.

A sophisticated shielding and filtering concept ensures that the interfaces are highly immune against radiation and do not deliver out any significant emission.

In most cases both units are shielded.