Radiation Effects On Fiber Optics

Samples representative of most of the optical fibers presently available in lengths of 10 m or more were tested for their responses to energetic radiation. Glass fibers doped with three different levels of cesium were also prepared and tested. Permanent and transient x-radiation effects tests were performed. Neutron effects tests were performed. All of the fibers tested showed decreases in transmission when exposed to radiation. All of the fibers emitted fluorescent light pulses when exposed to intense x-ray pulses.

Semi-transient and transient radiation-effects tests were performed on a Corning low-loss, radiation-resistant optical fiber. The semi-transient tests, which involved measurement of the fiber transmission during and after irradiation with X-rays, show this fiber to be much more resistant to permanent damage by radiation than other available glass fibers. The transient radiation-effects tests, in which the response of the fiber was measured during and for short times after pulses of X-rays and neutrons, show that the fiber may not be applicable to systems that cannot tolerate operational lapses of a few microseconds duration. This is because the fiber emits fluorescent radiation and shows temporary transmission losses during and shortly after pulses of radiation.