Title :
Highly efficient coupling between LD array and optical fiber array using Si microlens array
Author :
Nakagawa, Gohji ; Miura, Kazunori ; Makiuchi, Masao ; Yano, Mitsuhiro
Author_Institution :
Optical Device Lab., Fujitsu Labs. Ltd., Atsugi, Japan
Abstract :
By using a Si microlens array, highly efficient coupling is realized between laser diode (LD) and optical-fiber arrays. The Si microlens is fabricated by transferring the lens shape of photoresist onto the Si surface using an etching process. For an optimal coupling scheme, a high-NA microlens with a diameter of 240 mu m and focal length of 190 mu m is designed and fabricated. The optical coupling efficiency for a four-channel system is -4.8+or-0.3 dB between an LD array with lasing wavelength of 1.55 mu m and a single-mode fiber array, which is the best data reported so far. Optical crosstalk exceeds -70 dB at the 250- mu m distant neighbor channel.<>
Keywords :
crosstalk; integrated optics; lenses; optical couplers; optical fibres; optical interconnections; optical waveguides; 1.55 mum; 240 mum; LD array; Si; Si microlens array; Si surface; etching process; focal length; four-channel system; high-NA microlens; highly efficient coupling; lasing wavelength; lens shape; optical coupling efficiency; optical crosstalk; optical fiber array; optimal coupling scheme; photoresist; single-mode fiber array; Diode lasers; Lenses; Microoptics; Optical arrays; Optical coupling; Optical crosstalk; Optical fibers; Resists; Semiconductor laser arrays; Shape;
Journal_Title :
Photonics Technology Letters, IEEE
