LONG-PULSE LASER-ASSISTED SURFACE MODIFICATION OF AN IMAGING FIBER FOR FABRICATION OF INTEGRATED FIBER MICROLENSES

摘要

This paper discusses the results obtained with a long pulse laser (such as a CO_2 laser) assisted shaping of microspherical lenses at the end face of a specialty image fiber. The 600-μm-diameter image fiber consists of 15 000 pixels (individual fibers) with a spatial resolution of 267/mm. When laser-assisted heating is induced at the surface of the fiber tip, it tends to become spherical in shape due to surface tension. The curvature formed at the surface will act as the microspherical lens. The effects of the laser repetition rate and irradiation time on the surface finish and curvature of the shaped lens are illustrated in this paper.