Isamu Ohishi

A fiber lens with a long working distance for integrated coupling between laser diodes and single-mode fibers

A new scheme is proposed for lensed fibers with a long working distance, as used in the coupling between laser diodes and single-mode fibers. The scheme consists of the combination of a hemispherically-ended coreless-fiber tip and an expanded-core fiber. The working distance is measured as 169 /spl mu/m with a relatively low coupling-loss of 4.2 dB at a wavelength of 1.49 /spl mu/m. Tolerances for a 1-dB loss increment for axial-, lateral-, and angular-misalignment are 35, 2.6 /spl mu/m, and 0.8 degrees, respectively. The new configuration is suitable for alignment-free coupling between arrayed laser diodes and an array of single-mode fibers. >

A lensed-fiber coupling scheme utilizing a graded-index fiber and a hemispherically ended coreless fiber tip

A new configuration of lensed fibers as the coupling between laser diodes and single-mode fibers is proposed. The lensed fiber consists of a hemispherically ended coreless-fiber and a quarter-pitch length of a graded-index fiber. Fabrication is quite simple and rapid. Basic characteristics of the new configuration, including long working distances and wide tolerances, are experimentally verified. The new configuration is suitable for integration-oriented coupling between arrayed laser diodes and an array of single-mode fibers.

Integration-oriented lensed fibers having long working distances and wide tolerances

Summary form only given. In conclusion, a new lensed fiber structure for integrated coupling has been proposed. The basic operation is experimentally verified. The fabrication process is quite simple and suitable for mass-production.