Method of fabrication of fiber optic coupler

Claim 1

The method of fabricating an optical fiber coupler comprising: machining a solid form to develop a curved side having a preselected radius of curvature of between 5 and 8 cm; applying a coating of liquid epoxy resin on the curved side of the form; embedding a portion of an optical fiber in the liquid epoxy resin and allowing the resin to harden, thereby affixing the fiber to the form along the curved side thereof. repeating the first, second and third steps with a second solid form and a second optical fiber; mounting the two sections thus formed in a lapping and polishing fixture; lapping the epoxy and portions of the fibers embedded therein to develop essentially planar surfaces along the epoxy resin and fibers extending to a predetermined depth into the core of each fiber such that each fiber protrudes slightly above the planar surface of the adjacent epoxy; polishing the lapped surfaces; joining the two lapped and polished sections together at their planar surfaces along a common plane with optically transmitting epoxy; preliminarily aligning the fibers by initially moving the two sections parallel to each other along their planar surfaces to detect the protruding fibers contacting each other; finally aligning the two sections and the preliminarily aligned fibers thereof by focusing laser light into one of the fiber ends and monitoring the intensity of the light coupled into the other fiber while gradually adjusting the relative positions of the fibers; and curing the epoxy joining the two planar surfaces together while maintaining the established alignment thereof.

Claim 2

The method of fabricating an optical fiber coupler comprising: machining a solid form to develop a curved side having a preselected radius of curvature of between 5 and 8 cm; applying a coating of liquid epoxy resin on the curved side of the form; embedding a portion of an optical fiber in the liquid epoxy resin and allowing the resin to harden, thereby affixing the fiber to the form along the curved side thereof. repeating the first, second and third steps with a second solid form and a second optical fiber; mounting the two sections thus formed in a lapping and polishing fixture; lapping the epoxy and portions of the fibers embedded therein to develop essentially planar surfaces along the epoxy resin and fibers extending to a predetermined depth into the core of each fiber such that each fiber protrudes slightly above the planar surface of the adjacent epoxy; polishing the lapped surfaces; joining the two lapped and polished sections together at their planar surfaces along a common plane with optically transmitting epoxy; preliminarily aligning the fibers by initially moving the two sections parallel to each other along their planar surfaces to detect the protruding fibers contacting each other; finally aligning the two sections and the preliminarily aligned fibers thereof by focusing laser light into one of the fiber ends and monitoring the intensity of the light coupled into the other fiber while gradually adjusting the relative positions of the fibers; and curing the epoxy joining the two planar surfaces together while maintaining the established alignment thereof.