# US 2013/0156389 A1 · Composite optical fiber and method of the manufacturing of the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0156389 A1 - Document ID: US20130156389A1 - Status: Published application - Kind: A1 - Application number: 13/701,976 - Filed: 2011-06-06 - Published: 2013-06-20 - Earliest claimed: 2010-06-08 - Assignees: Japan Atomic Energy Agency; Kuraray Co., Ltd. - Inventors: Osamu Shinji; Katashi Saito; Kiyoshi Oka - Web page: https://patentgrep.com/patent/US20130156389A1 ## CPC - G02B 6/4486: {Protective covering} - A61B 1/00167: {Details of optical fibre bundles, e.g. shape or fibre distribution} - A61B 1/0017: {Details of single optical fibres, e.g. material or cladding} - A61B 1/07: using light-conductive means, e.g. optical fibres - G02B 6/02333: {Core having higher refractive index than cladding, e.g. solid core, effective index guiding} - G02B 6/02347: {Longitudinal structures arranged to form a regular periodic lattice, e.g. triangular, square, honeycomb unit cell repeated throughout cladding} - G02B 6/06: the relative position of the fibres being the same at both ends, e.g. for transporting images - G02B 23/2469: {using optical fibres} - G02B 23/26: using light guides {(for illumination G02B23/2469)} - A61B 1/0011: {Manufacturing of endoscope parts} - G02B 6/02033: {Core or cladding made from organic material, e.g. polymeric material (G02B1/04 takes precedence)} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract Disclosed is a composite optical fiber which has high flexibility and is hard to break. The composite optical fiber comprises a larger-diameter optical fiber and smaller-diameter optical fibers each having a smaller diameter than that of the larger-diameter optical fiber, wherein the larger-diameter fiber and the smaller-diameter optical fibers are so arranged that the larger-diameter fiber is surrounded by the smaller-diameter optical fibers, and the smaller-diameter optical fibers that surround the larger-diameter optical fiber are made from a plastic material. ## Claims ### Claim 1 A method of manufacturing a composite optical fiber, the method comprising: installing a plurality of elemental plastic optical fibers, each comprising a core portion and a cladding portion, between a plastic outer pipe and a plastic inner pipe, installing a core rod, comprising a transparent portion as an optical fiber's constituent element, inside of the plastic inner pipe, reducing an air pressure between the plastic outer pipe and the plastic inner pipe, and heating and drawing the plastic outer pipe, the elemental plastic optical fibers, the plastic inner pipe, and the core rod, with a gap portion among the plastic outer pipe, the element plastic optical fibers, the plastic inner pipe, and the core rod under a reduced-pressure condition. ### Claim 2 A method of manufacturing a composite optical fiber, the method comprising: installing a core rod, comprising a transparent portion as an optical fiber's constituent element, and elemental plastic optical fibers, each of the elemental plastic optical fibers comprising a core portion and a cladding portion, inside of a plastic pipe, thereby surrounding the core rod with a plurality of the elemental plastic optical fibers, reducing an air pressure within the plastic pipe, and heating and drawing the plastic pipe, the elemental plastic optical fibers, and the core rod with a gap portion among the plastic pipe, the elemental plastic optical fibers, and the core rod under a reduced-pressure condition. ### Claim 3 A method of manufacturing a composite optical fiber, the method comprising: installing a plurality of elemental plastic optical fibers, each comprising a core portion and a cladding portion, inside of a plastic outer pipe, installing a plastic inner pipe to be generally centered within the plastic outer pipe, reducing an air pressure between the plastic outer pipe and the plastic inner pipe, heating and drawing the plastic outer pipe, the elemental plastic optical fibers, and the plastic inner pipe with a gap portion among the plastic outer pipe, the elemental plastic optical fibers, and the plastic inner pipe under a reduced-pressure condition, and installing an optical fiber in the plastic inner pipe after the heating and drawing. ### Claim 4 A composite optical fiber comprising: a large-diameter optical fiber and small-diameter optical fibers, wherein diameters of the small-diameter optical fibers are smaller than a diameter of the large-diameter optical fiber, the large-diameter optical fiber is surrounded by the small-diameter optical fibers, the small-diameter optical fibers are plastic optical fibers each of the small-diameter optical fibers comprises a core portion and a cladding portion, and the small-diameter optical fibers have their cladding portions welded to one another. ### Claim 5 (depends on 1) A composite optical fiber, comprising: a large-diameter optical fiber and small-diameter optical fibers, wherein diameters of the small-diameter optical fibers are smaller than a diameter of the large-diameter optical fiber, the large-diameter optical fiber is surrounded by the small-diameter optical fibers, the small-diameter optical fibers are plastic optical fibers, each of the small diameter optical fibers comprises a core portion and a cladding portion, the small diameter optical fibers have their cladding portions welded to one another, and the composite optical fiber is obtained by a process comprising the method of claim 1. ### Claim 6 (depends on 4) The composite optical fiber of claim 4, wherein the large-diameter optical fiber has a diameter of from 30 μm to 300 μm, each of the small-diameter optical fibers comprises a core portion having a diameter of from 1 μm to 10 μm, and the composite optical fiber has an outer diameter of from 0.3 mm to 1.5 mm. ### Claim 7 (depends on 4) The composite optical fiber of claim 4, wherein a number of the small-diameter optical fibers is from 2,000 to 50,000. ### Claim 8 (depends on 4) The composite optical fiber of claim 4, wherein the large-diameter optical fiber comprises plastic. ### Claim 9 (depends on 4) The composite optical fiber of claim 4, wherein the large-diameter optical fiber comprises inorganic glass. ### Claim 10 (depends on 9) The composite optical fiber of claim 9, wherein the large-diameter optical fiber comprises an organic protective layer on its outer periphery. ### Claim 11 A hollow optical fiber assembly, comprising: small-diameter optical fibers installed between a plastic outer pipe and a plastic inner pipe, wherein the small-diameter optical fibers are plastic optical fibers, each of the small diameter optical fibers comprises a core portion and a cladding portion, and the cladding portions are welded to one another. ### Claim 12 (depends on 4) The composite optical fiber of claim 4, wherein the large-diameter optical fiber has a diameter of from 40 μm to 250 μm. ### Claim 13 (depends on 4) The composite optical fiber of claim 4, wherein the large-diameter optical fiber has a diameter of from 50 μm to 200 μm. ### Claim 14 (depends on 4) The composite optical fiber of claim 4, wherein the core portion of the small-diameter optical fibers has a diameter of 2 μm or more. ### Claim 15 (depends on 4) The composite optical fiber of claim 4, wherein the core portion of the small-diameter optical fibers has a diameter of 5 μm or less. ### Claim 16 (depends on 4) The composite optical fiber of claim 4, wherein the composite optical fiber has an outer diameter from 0.4 mm to 1.0 μm. ### Claim 17 (depends on 4) The composite optical fiber of claim 4, wherein a number of the small-diameter optical fibers is from 3,000 to 30,000. ### Claim 18 (depends on 4) The composite optical fiber of claim 4, wherein a number of the small-diameter optical fibers is from 5,000 to 20,000. ### Claim 19 (depends on 2) A composite optical fiber, comprising: a large-diameter optical fiber and small-diameter optical fibers, wherein diameters of the small-diameter optical fibers are smaller than a diameter of the large-diameter optical fiber, the large-diameter optical fiber is surrounded by the small-diameter optical fibers, the small-diameter optical fibers are plastic optical fibers, each of the small diameter optical fibers comprises a core portion and a cladding portion, the small diameter optical fibers have their cladding portions welded to one another, and the composite optical fiber is obtained by a process comprising the method of claim 2. ### Claim 20 (depends on 3) A composite optical fiber, comprising: a large-diameter optical fiber and small-diameter optical fibers, wherein diameters of the small-diameter optical fibers are smaller than a diameter of the large-diameter optical fiber, the large-diameter optical fiber is surrounded by the small-diameter optical fibers, the small-diameter optical fibers are plastic optical fibers, each of the small diameter optical fibers comprises a core portion and a cladding portion, the small diameter optical fibers have their cladding portions welded to one another, and the composite optical fiber is obtained by a process comprising the method of claim 3.