# US 2019/0170949 A1 · Bend induced light scattering fiber and cable assemblies and method of making > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170949 A1 - Document ID: US20190170949A1 - Status: Published application - Kind: A1 - Application number: 16/144,094 - Filed: 2018-09-27 - Published: 2019-06-06 - Earliest claimed: 2017-12-05 - Assignees: Corning Research & Development Corporation - Applicants: Corning Research & Development Corporation - Inventors: Adam Kent Collier - Web page: https://patentgrep.com/patent/US20190170949A1 ## CPC - G02B 6/02: Optical fibres with cladding {with or without a coating} - G02B 6/3879: {Linking of individual connector plugs to an overconnector, e.g. using clamps, clips, common housings comprising several individual connector plugs} - G02B 6/38875: {Protection from bending or twisting} - G02B 6/3893: {Push-pull type, e.g. snap-in, push-on} - G02B 6/562: {locatable, e.g. using magnetic means} - G02B 6/3878: {comprising a plurality of ferrules, branching and break-out means} - G02B 6/3888: {Protection from over-extension or over-compression} - G02B 6/3895: {identification of connection, e.g. right plug to the right socket or full engagement of the mating parts (keying element on the plug or adapter G02B6/3831; keying element on the ferrule G02B6/3851; keying element for electrical connection H01R13/64)} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract Embodiments of the disclosure are directed to a bend induced light scattering (BIS) optical fiber and method of making. The BIS optical fiber includes a core of pure silica devoid of nanovoids and a cladding surrounding the core. The core has a first index of refraction and the cladding has a second index of refraction that is lower than the first index of refraction of the core. The first index of refraction of the core and the second index of refraction of the cladding are configured to maintain light within the core when the BIS optical fiber is unbent in a light retaining position and to emit light from the core to the cladding at a bend in the BIS optical fiber when the radius of curvature of the bend is less than a critical radius of curvature and the BIS optical fiber is in a light emitting position. ## Claims ### Claim 1 An optical communication cable assembly including a bend-induced light scattering (BIS) optical fiber, comprising: a cable comprising at least one data transmission fiber, a bend-induced light scattering (BIS) optical fiber, and a jacket; a first connector at a first end of the jacket; and a second connector at a second end of the jacket, wherein the BIS optical fiber comprising an entry bend positioned in the first connector and an emission bend positioned in the second connector; the BIS optical fiber further comprising: a core comprising pure silica and being devoid of nanovoids, the core having a first index of refraction; and a cladding surrounding the core, the cladding having a second index of refraction that is lower than the first index of refraction of the core; wherein the first index of refraction of the core and the second index of refraction of the cladding are configured to maintain light within the core when the BIS optical fiber is unbent in a light retaining position and to emit light from the core to the cladding at a bend in the BIS optical fiber when a radius of curvature of the bend is less than a critical radius of curvature and the BIS optical fiber is in a light emitting position; and wherein the BIS optical fiber is selectively movable from the light emitting position in which the radius of curvature is less than the critical radius of curvature and the light retaining position in which the radius of curvature is greater than the critical radius of curvature without damaging the core or the cladding of the BIS optical fiber. ### Claim 2 (depends on 1) The optical communication cable assembly of claim 1, wherein the emission bend is less than the critical radius of curvature. ### Claim 3 (depends on 2) The optical communication cable assembly of claim 2, wherein the emission bend is equal to or greater than about 90 degrees. ### Claim 4 (depends on 2) The optical communication cable assembly of claim 2, wherein the emission bend is equal to or greater than about 180 degrees. ### Claim 5 (depends on 2) The optical communication cable assembly of claim 2, wherein the entry bend is greater than the critical radius of curvature. ### Claim 6 (depends on 1) The optical communication cable assembly of claim 1, wherein the first connector comprises an entry channel to maintain the entry bend of the BIS optical fiber above the critical radius of curvature. ### Claim 7 (depends on 6) The optical communication cable assembly of claim 6, wherein the second connector comprises an emission channel to maintain the emission bend of the BIS optical fiber below the critical radius of curvature. ### Claim 8 (depends on 7) The optical communication cable assembly of claim 7, wherein the emission channel provides about a 270 degree bend. ### Claim 9 (depends on 1) The optical communication cable assembly of claim 1, wherein at least a portion of the first connector is translucent and at least a portion of the second connector is translucent. ### Claim 10 A method of manufacturing an optical communication cable assembly having a bend-induced light scattering (BIS) optical fiber, comprising: forming a cable comprising a jacket, at least one data transmission fiber, and a bend-induced light scattering (BIS) optical fiber, wherein the BIS optical fiber comprises a core comprising pure silica and being devoid of nanovoids and a cladding around the core, the core having a first index of refraction and the cladding having a second index of refraction that is lower than the first index of refraction of the core, the first index of refraction of the core and the second index of refraction of the cladding configured to maintain light within the core when the BIS optical fiber is unbent in a light retaining position and to emit light from the core to the cladding at a bend in the BIS optical fiber when a radius of curvature of the bend is less than a critical radius of curvature and the BIS optical fiber is in a light emitting position; securing a first connector at a first end of the cable; securing a second connector at a second end of the cable; and creating an entry bend in the BIS optical fiber and positioning the entry bend in the first connector; and creating an emission bend and positing the emission bend in the second connector, wherein the emission bend is less than the critical radius of curvature. ### Claim 11 (depends on 10) The method of claim 10, wherein the emission bend is equal to or greater than about 90 degrees. ### Claim 12 (depends on 10) The method of claim 10, wherein the emission bend is equal to or greater than about 180 degrees. ### Claim 13 (depends on 10) The method of claim 10, wherein the entry bend is greater than the critical radius of curvature. ### Claim 14 (depends on 10) The method of claim 10, wherein the first connector comprises an entry channel to maintain the entry bend greater than the critical radius of curvature. ### Claim 15 (depends on 10) The method of claim 10, wherein the second connector comprises an emission channel to maintain the emission bend less than the critical radius of curvature. ### Claim 16 (depends on 15) The method of claim 15, wherein the emission channel provides about a 270 degree bend. ### Claim 17 A bend-induced light scattering (BIS) optical fiber, comprising: a core comprising pure silica and being devoid of nanovoids, the core having a first index of refraction; and a cladding surrounding the core, the cladding having a second index of refraction that is lower than the first index of refraction; wherein the first index of refraction of the core and the second index of refraction of the cladding are configured to maintain light within the core when the BIS optical fiber is unbent in a light retaining position and to emit light from the core to the cladding at a bend in the BIS optical fiber when a radius of curvature of the bend is less than a critical radius of curvature and the BIS optical fiber is in a light emitting position; and wherein the BIS optical fiber is selectively movable from the light emitting position in which the radius of curvature is less than the critical radius of curvature and the light retaining position in which the radius of curvature is greater than the critical radius of curvature without damaging the core or the cladding of the BIS optical fiber. ### Claim 18 (depends on 17) The BIS optical fiber of claim 17, wherein the core comprises a diameter between about 80 μm and about 250 μm and the cladding comprises a diameter between about 100 μm and about 350 μm. ### Claim 19 (depends on 18) The BIS optical fiber of claim 18, wherein the light emitted from the core to the cladding is between about 0.2 dB and about 2 dB over 1 mm to 75 mm of fiber length at the bend when the radius of curvature is between about 2 mm to about 3.5 mm. ### Claim 20 (depends on 19) The BIS optical fiber of claim 19, wherein the core comprises a high purity fused silica core with about a 125 μm diameter and a first index of refraction between 1.46 and 1.47 measured at 532 nm; wherein the cladding comprises has a diameter between about 155 μm and about 160 μm and a second index of refraction of about 1.38 measured at 589 nm; wherein the critical radius of curvature is between about 1.9 mm and 3 mm. ### Claim 21 (depends on 17) The BIS optical fiber of claim 17, wherein the cladding comprises a first fluorinated acrylate cladding layer with diameter between about 100 μm and about 170 μm and a second acrylate cladding layer with a diameter between about 140 μm and about 250 μm. ### Claim 22 (depends on 17) The BIS optical fiber of claim 17, wherein the cladding comprises a light scattering mechanism. ### Claim 23 (depends on 22) The BIS optical fiber of claim 22, wherein the light scattering mechanism comprises light scattering ink.