Optimization of the optical coupling efficiency of fiber with Gaussian pulsed laser

Abstract

In the photoacoustic microscopy coupled with the optical fiber, the photoacoustic intensity of the irradiated tissue is one of most important factors of Furthermore, the coupling coefficient of the fiber also impacts the final irradiated laser energy. Furthermore, the coupling coefficient of the fiber also impacts the final irradiated laser energy. At the characteristic wavelength of 532nm, the effects of the optical positions of the With the operations of parameters scanning, the optimal values of the optical positions of the focusing lens and optical fiber on the coupling efficiency of the fiber were investigated. values of the optical positions of the focusing lens and optical fiber were obtained under the maximum coupling efficiency of the fiber. After that, the effect of the fiber's mode field diameter on the coupling efficiency of fiber under the optimal positions of the focusing lens and fiber was also investigated. The coupling efficiencies of fiber corresponding to seven different mode field diameters of fiber from 1 to 9μm were computed, the The study results show that with the increase of the mode field Under the optimal positions of the focusing lens and the fiber, as well as the mode field diameter, the optical efficiency of fiber first increase then decrease. Under the optimal positions of the focusing lens and the fiber, as well as the mode field diameter, the optical efficiency of fiber can be improved from 23.174% to 91.638%. Therefore, the reasonable positions of the optical path and the mode field diameter of the fiber are all important to ensure the satisfactory optical Therefore, the reasonable positions of the optical path and the mode field diameter of the fiber are all important to ensure the satisfactory optical coupling efficiency in the photoacoustic microscopy system coupled with the optical fiber.