Coupling structure between a semiconductor laser and an optical fiber and coupling method thereof

Abstract

In a coupling structure for directly coupling a semiconductor laser to an optical fiber without using a lens, a coupling structure is provided which is superior in producibility, low in coupling loss and stable in operation of the semiconductor laser, by removing an influence of a return light due to Fresnel reflection from an end face of the optical fiber. A re-combination of the semiconductor laser to an active layer of the optical fiber is prevented by scattering a reflection light at the end face of the optical fiber by positively increasing a surface roughness Rz of the end face of the optical fiber to a range from 0.04 .mu.m to 0.06 .mu.m. The end face is formed by cutting the optical fiber with a blade saw having abrasive of particle size in a range from #1000 gauge to #2000 gauge corresponding to a range from 8 .mu.m to 20 .mu.m. The end face may be polished with abrasive having size in a rage from #1000 to #2000 gauge.

Dependencies are inferred from the claim text.