Patent ID: 7111993

Claim:
An optical monitor module comprising: a substrate having formed in one surface thereof a positioning structure for positioning a plurality of optical fibers in parallel and for determining positions of said optical fibers in a direction perpendicular to said one surface; first and second optical fibers mounted in parallel on said substrate by said positioning structure, said first optical fiber having an axis and a lens portion with a graded-index fiber formed integrally in one end of the first optical fiber for emitting light at an angle inclined to said axis of the first optical fiber, and said second optical fiber having an axis and a lens portion with a graded-index fiber formed integrally in one end of the second optical fiber for receiving light at an angle inclined to said axis of the second optical fiber; and a beam splitter or optical filter mounted on said substrate at a position between an extension of said axis of said first optical fiber and an extension of said axis of said second optical fiber, for receiving light emitted along a first optical path from said lens portion of said first optical fiber and for reflecting a portion of said light along a second optical path to said lens portion of said second optical fiber; wherein said first optical path and said second optical path are through space.