The ferrule has a rear end and a front end, an opening that is formed in the rear end and communicates with fiber holding holes holding the optical fibers formed from the rear end toward the front end, and first connection parts which are formed at the front end and to which the lens array is connected. The lens array has a rear face and a surface including an outgoing plane, lenses receiving the light from the optical fibers, and second connection parts connected to the first connection parts, the lenses and the second connection parts being formed on the rear face, and a flat face from which the light from the optical fibers is emitted, and third connection parts connected to an opposite connector, the flat face and the second connection parts being formed on the surface.

According to an aspect of the invention, an optical receptacle, comprising: a fiber stub including an optical fiber, a ferrule, and an elastic member, the optical fiber including cladding and a core for conducting light, the ferrule having a through-hole fixing the optical fiber, the elastic member being filled into the through-hole of the ferrule with the optical fiber; and a holder holding the fiber stub, the through-hole of the ferrule including a small diameter portion and a large diameter portion, the optical fiber being disposed in the small diameter portion, the large diameter portion being provided on a side opposite to a side to be optically connected to a plug ferrule, the optical fiber being disposed in the small diameter portion inside the through-hole of the ferrule over the entire region of the optical fiber, the elastic member having substantially the same refractive index as the core, being filled into the small diameter portion and the large diameter portion, and being polished to cause at least a portion of the elastic member to be a flat surface portion at an end surface of the fiber stub on the side opposite to the side to be optically connected to the plug ferrule. By disposing the optical fiber in the small diameter portion of the through-hole of the ferrule over the entire region of the optical fiber, the breaking and/or cracking of the optical fiber and the decrease of the coupling efficiency can be prevented. Further, by setting the end surface of the elastic member filled into the through-hole of the ferrule to be a flat surface, the decrease of the coupling efficiency due to reflections is prevented without performing processing of the optical fiber end surface; and economic production is made possible.

A unitary multi-fiber ferrule has micro-holes for optical fibers, an optical stop plane for the optical fibers, and a plurality of lenses disposed adjacent the front end, each of the plurality of lenses optically aligned with one of the micro-holes and exposed to air. Multiple rows of optical fibers and lenses may also be used in the unitary multi-fiber ferrule. The unitary multi-fiber ferrule requires less processing and equipment than other current optical ferrules.

A method of manufacturing an optical connector according to the invention includes: holding a first optical fiber by a pair of holding members at a position apart from an end face of a second end and through both sides thereof in a radial direction, the first optical fiber being provided with a solid refractive index-matching material layer, the refractive index-matching material layer being formed on the end face of the second end on an opposite side of an end face of a first end exposed to a front end of a ferrule; and inserting the first optical fiber into a fiber hole of the ferrule through the first end.

A low-reflection fiber-optic connector. The fiber-optic connector includes a ferrule that includes a fiber passage and an optical fiber traversing the fiber passage. The optical fiber includes a polished fiber end that is substantially flush with a ferrule end face. The ferrule end face, in an area surrounding the polished fiber end, is modified to reduce an optical reflectivity.

An optical fiber splicer includes a fiber fixing portion, a first optical fiber fixed to the fiber fixing portion, a clamp portion which is capable of holding and fixing an extending portion extended from the fiber fixing portion of the first optical fiber and a tip portion of a second optical fiber optically connected to the extending portion of the first optical fiber between a base member and a pressing member being openable and closable with respect to the base member, and a solid index matching material which is attached to a tip surface of the extending portion of the first optical fiber and is interposed between the first optical fiber and the second optical fiber.

A terminus for a fiber optic cable includes a ferrule. In one embodiment, an optical fiber of the cable passes through a central bore of the ferrule and is attached to a lens seated in a conical or cylindrical seat formed in an end surface of the ferrule by an epoxy. In a second embodiment, an optical fiber of the cable passes through the central bore of the ferrule. Next, a cap sleeve with a lens therein is slid over and attached to the ferrule such that the lens abuts or is attached to the optical fiber. In either embodiment, an inspection slot may optionally be formed in the ferrule and/or the cap sleeve to allow a technician to inspect the state of the attachment and/or abutment and/or spacing of the optical fiber and the lens.

According to an aspect of the invention, an optical receptacle, comprising: a fiber stub including an optical fiber, a ferrule, and an elastic member, the optical fiber including cladding and a core for conducting light, the ferrule having a through-hole fixing the optical fiber, the elastic member being filled into the through-hole of the ferrule with the optical fiber; and a holder holding the fiber stub, the through-hole of the ferrule including a small diameter portion and a large diameter portion, the optical fiber being disposed in the small diameter portion, the large diameter portion being provided on a side opposite to a side to be optically connected to a plug ferrule, the optical fiber being disposed in the small diameter portion inside the through-hole of the ferrule over the entire region of the optical fiber, the elastic member having substantially the same refractive index as the core, being filled into the small diameter portion and the large diameter portion, and being polished to cause at least a portion of the elastic member to be a flat surface portion at an end surface of the fiber stub on the side opposite to the side to be optically connected to the plug ferrule. By disposing the optical fiber in the small diameter portion of the through-hole of the ferrule over the entire region of the optical fiber, the breaking and/or cracking of the optical fiber and the decrease of the coupling efficiency can be prevented. Further, by setting the end surface of the elastic member filled into the through-hole of the ferrule to be a flat surface, the decrease of the coupling efficiency due to reflections is prevented without performing processing of the optical fiber end surface; and economic production is made possible.

An optical fiber connection structure is provided, in which a first optical fiber and a second optical fiber, which is optically connected to the first optical fiber via a solid refractive index-matching material which is provided on a tip surface of the first optical fiber, are held and fixed between a base member and a cover member, a tip of the second optical fiber is disposed so as to come into contact with the solid refractive index matching material or separated from the solid refractive index-matching material, and the entire solid refractive index matching material and the tip of the second optical fiber are disposed in a liquid refractive index matching agent which is provided between the base member and the cover member.

A unitary multi-fiber ferrule has micro-holes for optical fibers, an optical stop plane for the optical fibers, and a plurality of lenses disposed adjacent the front end, each of the plurality of lenses optically aligned with one of the micro-holes and exposed to air. Multiple rows of optical fibers and lenses may also be used in the unitary multi-fiber ferrule. The unitary multi-fiber ferrule requires less processing and equipment than other current optical ferrules.