Uniform Side-Glowing Polymer Optical Fiber Fabricated by Laser-Marking
【Abstract】A new method for the fabrication of a uniform side-glowing polymer optical fiber (POF) is investigated. The varied-line-space (VLS) grating scattering points are fabricated on the side of POF by laser-marking. The model of VLS grating scattering points by laser-marking is established, which is composed of shallow surface pits and scattering regions where scattering particles are distributed. The relative scattering power of scattering points and the calculating formula of VLS are derived theoretically. The change law of scattering light power of scattering points versus pit depth and particle density is analyzed. The distribution rule of VLS grating pitch versus pit depth and relative emissivity of side-glowing POF is also discussed. The results show that the tiny variation (μm level) of pit depth of scattering points has a great influence on scattering light power and VLS grating pitch. When scattering particle density is N < 105 mm−3, the variance of scattering light power with the scattering point density is small. In contrast, if the scattering particle density is N > 105 mm−3, the variance becomes obvious. The distribution curves of VLS grating pitch under different pit depths and relative emissivities are calculated theoretically, which are verified by experiments. In experiments, a side-glowing POF with a luminance uniformity of larger than 90% is obtained just by the adjustment of laser-marking power.
【Keywords】 fiber optics; polymer optical fiber; side-glowing; laser-marking technique; varied-line-space grating; scattering points;
(Translated by LIU T)
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