Patent ID: 9389375
Filing Date: 2016-07-12
CPC Classification: G02B

Claim Text:
1. An optical coupling element configured to be able to optically couple a plurality of light emitting elements and end surfaces of a plurality of optical fibers in such a state as to be disposed between the plurality of light emitting elements and the plurality of optical fibers, the optical coupling element comprising: a plurality of incidence surfaces having a curvature disposed to correspond to each of the plurality of light emitting elements, on a first surface closer to the plurality of light emitting elements, of a optical coupling element main body and allowing each light emitted from the plurality of light emitting elements to enter the plurality of incidence surfaces; a reflection surface having a curvature disposed to have an inclination relative to the first surface, on a second surface opposite to the first surface, of the optical coupling element main body and reflecting each light from the plurality of light emitting elements having entered the plurality of incidence surfaces toward the plurality of optical fibers; and a plurality of emission surfaces having a curvature disposed to correspond to each of the end surfaces of the plurality of optical fibers, on a third surface, closer to the plurality of optical fibers, of the optical coupling element main body and emitting each light from the plurality of light emitting elements having been reflected by the reflection surface toward the end surfaces of the plurality of optical fibers, wherein: in a case where, when the plurality of incidence surfaces are aligned and disposed to form only a single row in an alignment direction of the single row, the alignment direction is defined as “X direction,” a traveling direction of the light emitted from the plurality of light emitting elements is defined as “Z direction,” and a direction orthogonal to the X and Z directions is defined as “Y direction,” and on a supposition that the plurality of light emitting elements are moved from a position at which each optical coupling efficiency between the plurality of light emitting elements and the end surfaces of the plurality of optical fibers demonstrates a preset maximum efficiency to a position at which a predetermined decrease in optical coupling efficiency based on the maximum efficiency is demonstrated, a distance in the X direction between the position before the movement and the position after the movement is defined as “X direction tolerance,” and a distance in the Y direction between the position before the movement and the position after the movement is defined as “Y direction tolerance,” curvatures of the incidence surface, the reflection surface, and the emission surface are adjusted such that the X direction tolerance is greater than the Y direction tolerance.