Masuda S, Iwama T
Fujitsu Laboratories, Ltd., 1015 Kamikodanaka Nakahara-ku, Kawasaki 211, Japan.
Appl Opt. 1982 Oct 1;21(19):3484-8. doi: 10.1364/AO.21.003484.
A low-loss compact single-mode fiber optical directional coupler (SMF-ODC) is developed for use in SMF reflectometers or gyroscopes. The SMF-ODC is made of two sapphire ball lenses, a half-mirror, and two ferrules. Two fibers (endfaces are concave) are aligned parallel to each other in the ferrule. The optical and mechanical axes are tilted. Cross-talk light from fibers or lenses is avoided. The SMF-ODC excess loss is 1.5-2.5 dB at the 1.2-1.5-microm wavelength range. The directivity is 53 (51) dB at the 1.3 (1.53)-microm wavelength. The light polarization dependency is < or =0.1 dB. The return loss is > or =43 dB.
一种低损耗紧凑型单模光纤光定向耦合器（SMF - ODC）被开发用于单模光纤反射计或陀螺仪。该SMF - ODC由两个蓝宝石球透镜、一个半反射镜和两个插芯组成。两根光纤（端面为凹面）在插芯中彼此平行排列。光轴和机械轴倾斜。避免了来自光纤或透镜的串扰光。在1.2 - 1.5微米波长范围内，SMF - ODC的额外损耗为1.5 - 2.5分贝。在1.3（1.53）微米波长处，方向性为53（51）分贝。光偏振依赖性小于或等于0.1分贝。回波损耗大于或等于43分贝。
