Gamma radiation effects on plastic optical fibers

We report on our study of the effect of gamma-ray irradiation on Plastic Optical Fibers with a 1 mm diameter for short reach communication. For the study, we used gamma-radiation facilities with Co-60 sources for slow long-term irradiation with a low dose speed of around 70 Gy/hrs and a maximum dose up to 62.90 kGy and a higher speed irradiation dose of around 1 kGy/hrs with a maximum dose up to 51.30 kGy. The optical losses measurement showed that the losses increased linearly during the irradiation and began to decrease immediately after the end of being irradiated. Higher doses of irradiation cause a higher value of the optical loss, and at the dose of 62.9 kGy, the loss was unmeasurably high. A low dose of gamma radiation (1.24 kGy) increased optical losses only slightly and the gamma-ray irradiation at 17.6 kGy for the 20 m long fiber had optical losses of -15.5 dB at 650 nm. The results of the relaxation measurements also showed that optical losses measured at wavelength 535 nm are significantly higher than those at 650 nm. Spectral characteristics measurement done during the irradiation showed that the intensity of the transmitted light decreased and the absorption edge shifted towards the higher wavelengths. Spectral characteristics measured after irradiation during the relaxation period showed that the intensity increased and also that the absorption edge was shifted towards the lower wavelengths, but the same values as before the irradiation were not achieved.

Automated summary

We conducted a study on the impact of gamma-ray irradiation on Plastic Optical Fibers (POFs) used for short reach communication. The results showed that irradiation caused an increase in optical losses, which started to decrease immediately after the irradiation. Higher doses of irradiation resulted in higher optical losses, with some doses reaching unmeasurable levels. Low doses of gamma radiation had minimal impact on optical losses. Spectral characteristics measurements showed that the intensity of transmitted light decreased during irradiation, and after the irradiation, the intensity increased while the absorption edge shifted towards lower wavelengths, but not reaching the pre-irradiation values.