摘要
报道了宽频带单模光纤定向耦合器的制作与理论，作者设法让两光纤在熔锥区的特性不同，形成非对称臂的两段式准双锥体波导，并分别用变分理论和传统的耦合波理论分析腰部区域和梯度区域的耦合行为。耦合器的耦合功率应是这两区域耦合功率的叠加．用这种方法研制的非对称臂耦合器，其光功率在两光纤间不能实现完全转换，若两光纤在熔锥区的特性差异恰当，可使某功率分束比（如３ｄＢ）的转换点处在该分束比随波长变化的极值点，在该点附近的一定范围内，功率随波长变化很不灵敏，从而得到波长响应平坦的宽带耦合器。
The manufacture and theory of a wide band single-mode fibre directionalcoupler are presented in this paper. Using the different fuse-tapered characteristicsof two fibres,we made a two-section quasi-cone-shaped waveguide of unsymmet-rical arms.By means of variational caleulus and the standard theory of eoupledwaves,the coupling behaviors of the waist zone and the trapezoidal zone are ana-lysed;the coupling power of the coupler equals the sum of the coupling powers ofthese two areas; and the light power of the unsymmetrical arm coupler formed inttis way can not be completely transformed between the two fibres. With proper differences of the characteristics in the fuse-tapered area of thetwo fibres,the transformation Point of certain power splitting ratio(e,g.,3dB)can be located at the point of extreme value of the ratio against the change ofwavelength. In the area near the point,sensitivity of the power change to wave-length is low. Thus a single-mode coupler of wide band is obtained.
出处
《应用科学学报》
CAS
CSCD
1995年第3期288-298,共11页
Journal of Applied Sciences
关键词
定向耦合器
熔锥型耦合器
光纤定向耦合器
fuse-tapered coupler,wide band fibre coupler, fibre directional coupler
