Chiang Kin Seng
Department of Electronic Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong.
Appl Opt. 2009 Sep 1;48(25):F61-7. doi: 10.1364/AO.48.000F61.
A long-period fiber grating (LPFG) formed in a single-mode fiber is considered as an effective device to tap light from the core of fiber. This light-tapping property of the LPFG allows a new class of wavelength-selective optical couplers to be realized by using the configuration of parallel LPFGs. Over the years a number of four-port and six-port LPFG couplers with peak coupling efficiencies greater than 80% have been demonstrated. To further increase the functionality of LPFG couplers and facilitate device packaging and integration, long-period grating couplers formed in planar waveguides have also been proposed, and the preliminary results are promising. A review of these coupling devices is presented.
单模光纤中形成的长周期光纤光栅（LPFG）被视为从光纤纤芯中提取光的有效器件。LPFG的这种光提取特性使得通过使用平行LPFG的配置能够实现一类新型的波长选择性光耦合器。多年来，已经展示了许多峰值耦合效率大于80%的四端口和六端口LPFG耦合器。为了进一步增加LPFG耦合器的功能并便于器件封装和集成，还提出了在平面波导中形成的长周期光栅耦合器，初步结果很有前景。本文对这些耦合器件进行了综述。
