【摘要】 本文提出了由模折射率确定波导表面折射率的新方法,简化了White提出的公式,且可适用于任意折射率分布的平面光波导,具有普遍意义。分析结果表明,理论计算与实验测量相符合。更多还原

【Abstract】 The K9 glass substrate made in China were dipped in the silver melts at 270~300? temperature, the Ag+-Na+ ion exchange was made under the constant temperature condition, and the planar optical waveguides of graded index profile have been fabricated. Mode indices of these waveguide samples have been measured with a symmetric prism coupler at 6328 A laser wavelength.In this paper, white and Heidrich’s oaloulational formulae determing the waveguide index profile by mode indices have been reduced, and simple new methods determing the waveguide surface index by mode indices have been presented. On this basis, it is determined by mode index measurement values that the refractive index profile of K9 glass waveguides formed by ion exchange iswhere ns = 1 . 5930 and nb = 1.5146 are refractive indices of waveguide surface and subs trate respectively, ? =0.66 is the second -order term coefficient, d is the effective diffus ion depth, and x is the distance from waveguide surface.For the second-order polynominal profile of optical waveguide index the mode equation and cut-off equation have been derived, from which the mode dispersion and cut-off properties have been analysed, and fabrication technical conditions of single-mode and multi-mode waveguides have been given.Analytical results show that theoretical calculations are identical with experimental measuements. This paper provided necessary basic informations for fabrications of single-mode and multi-mode waveguide devices required by optical fiber communication systems with K9 glass waveguides formed by ion exchange.更多还原