[LUO, Wenyong, YU, Huang, WU, Shujian, LI, Wei, YU, Zhiqiang, DU, Cheng, KE, Yili, ZHANG, Tao, ZHU, Qiao, ZENG, Fanqiu] No.6 High-Tech 4 Road East Lake High-Tech Zone, Wuhan, Hubei 430000, CN An ultra-low attenuation large effective area single-mode optical fiber, comprising a core layer (1), a first cladding layer (2), a second cladding layer (3), a third cladding layer (4), and a fourth cladding layer (5) arranged in sequence from inside to outside; the first cladding layer (2) is fluorine-doped quartz; the second cladding layer (3), the third cladding layer (4), and the fourth cladding layer (5) are quartz; the third cladding layer (4) is provided with at least one annular microporous layer successively arranged from inside to outside, the annular microporous layer comprising a plurality of evenly distributed micropores (40), the circle centers of the micropores (40) in each annular microporous layer being cocircular, and the circle being concentric with the core layer (1); the core layer (1) is alkali metal-doped quartz, the core layer (1) comprising an inner core layer (10) and a transition core layer (11) arranged in sequence from inside to outside; the relative refractive index difference aa between the transition core layer (11) and the fourth cladding layer (5) satisfies bb, wherein a is the transition coefficient of the transition core layer (11), and x is the distance from any point in the transition core layer (11) to the edge of the inner core layer (10). The present single-mode optical fiber has ultra-low attenuation and a large effective area, and can implement large-mode field optical fiber transmission and reduce the non-linear effect of large capacity transmission. ＜maths id="matha01" num=""＞＜math display="block"＞＜mtable＞＜mtr＞＜mtd＞＜mrow＞＜mi＞Δ＜/mi＞＜msub＞＜mi mathvariant="normal"＞n＜/mi＞＜mn＞11＜/mn＞＜/msub＞＜/mrow＞＜/mtd＞＜mtd＞＜mi＞aa＜/mi＞＜/mtd＞＜/mtr＞＜/mtable＞＜/math＞＜img id="ia01" file="imga0001.tif" wi="25" he="5" img-content="math" img-format="tif" /＞＜/maths＞ ＜maths id="matha02" num=""＞＜math display="block"＞＜mtable＞＜mtr＞＜mtd＞＜mrow＞＜mi＞Δ＜/mi＞＜msub＞＜mi mathvariant="normal"＞n＜/mi＞＜mi＞11＜/mi＞＜/msub＞＜mo＞=＜/mo＞＜mo＞−＜/mo＞＜mfrac＞＜msup＞＜mi＞ax＜/mi＞＜mi mathvariant="normal"＞2＜/mi＞＜/msup＞＜mn＞100＜/mn＞＜/mfrac＞＜msup＞＜mi＞lga＜/mi＞＜mi mathvariant="normal"＞x＜/mi＞＜/msup＞＜/mrow＞＜/mtd＞＜mtd＞＜mi＞bb＜/mi＞＜/mtd＞＜/mtr＞＜/mtable＞＜/math＞＜img id="ia02" file="imga0002.tif" wi="47" he="11" img-content="math" img-format="tif" /＞＜/maths＞＜img id="iaf01" file="imgaf001.tif" wi="165" he="64" img-content="drawing" img-format="tif" /＞

[LUO, Wenyong 罗文勇, YU, Huang 喻煌, WU, Shujian 伍淑坚, LI, Wei 李伟, YU, Zhiqiang 余志强, DU, Cheng 杜城, KE, Yili 柯一礼, ZHANG, Tao 张涛, ZHU, Qiao 朱侨, ZENG, Fanqiu 曾凡球] No.6 High-tech 4 Road, East Lake High-tech Zone 中国湖北省武汉市东湖高新技术开发区高新四路6号, Hubei 430000Wuhan, Hubei 430000;No.42 Optics Valley Chuangye Street 中国湖北省武汉市光谷创业街42号, Hubei 430074Wuhan, Hubei 430074;Building 1 & 2, Guandong Science And Technology Park, East Lake Development Zone 中国湖北省武汉市东湖开发区关东科技园1、2号楼, Hubei 430000Wuhan, Hubei 430000 An ultra-low attenuation large effective area single-mode optical fibre, comprising a core layer (1), a first cladding layer (2), a second cladding layer (3), a third cladding layer (4), and a fourth cladding layer (5) arranged in sequence from inside to outside; the first cladding layer (2) is fluorine-doped quartz; the second cladding layer (3), the third cladding layer (4), and the fourth cladding layer (5) are quartz; the third cladding layer (4) is provided with at least one annular microporous layer sequentially arranged from inside to outside, the annular microporous layer comprising a plurality of evenly distributed micropores (40), the circle centres of the micropores (40) in each annular microporous layer being cocircular, and the circle being concentric with the core layer (1); the core layer (1) is alkali metal-doped quartz, the core layer (1) comprising an inner core layer (10) and a transition core layer (11) arranged in sequence from inside to outside; the relative refractive index difference aa between the transition core layer (11) and the fourth cladding layer (5) satisfies bb, wherein a is the transition coefficient of the transition core layer (11), and x is the distance from any point in the transition core layer (11) to the edge of the inner core layer (10). The present single-mode optical fibre has ultra-low attenuation and a large effective area, and can implement large-mode field optical fibre transmission and reduce the non-linear effect of large capacity transmission. An ultra-low attenuation large effective area single-mode optical fibre, comprising a core layer (1), a first cladding layer (2), a second cladding layer (3), a third cladding layer (4), and a fourth cladding layer (5) arranged in sequence from inside to outside; the first cladding layer (2) is fluorine-doped quartz; the second cladding layer (3), the third cladding layer (4), and the fourth cladding layer (5) are quartz; the third cladding layer (4) is provided with at least one annular microporous layer sequentially arranged from inside to outside, the annular microporous layer comprising a plurality of evenly distributed micropores (40), the circle centres of the micropores (40) in each annular microporous layer being cocircular, and the circle being concentric with the core layer (1); the core layer (1) is alkali metal-doped quartz, the core layer (1) comprising an inner core layer (10) and a transition core layer (11) arranged in sequence from inside to outside; the relative refractive index difference aa between the transition core layer (11) and the fourth cladding layer (5) satisfies bb, wherein a is the transition coefficient of the transition core layer (11), and x is the distance from any point in the transition core layer (11) to the edge of the inner core layer (10). The present single-mode optical fibre has ultra-low attenuation and a large effective area, and can implement large-mode field optical fibre transmission and reduce the non-linear effect of large capacity transmission.

[LUO, Wenyong 罗文勇, YU, Huang 喻煌, QI, Wei 戚卫, YU, Zhiqiang 余志强, WU, Shujian 伍淑坚, KE, Yili 柯一礼, DU, Cheng 杜城, ZHU, Qiao 朱侨, ZENG, Fanqiu 曾凡球] No. 6 High-Tech 4 Road, East Lake High-Tech Zone 中国湖北省武汉市东湖高新技术开发区高新四路6号, Hubei 430000Wuhan, Hubei 430000;No. 42 Optics Valley Chuangye Street 中国湖北省武汉市光谷创业街42号, Hubei 430074Wuhan, Hubei 430074;Building 1 & 2, Guandong Science And Technology Park, East Lake Development Zone 中国湖北省武汉市东湖开发区关东科技园1、2号楼, Hubei 430000Wuhan, Hubei 430000 Disclosed are an optical fiber preform and method used for fabricating an ultra-low attenuation optical fiber, and an optical fiber. The optical fiber preform comprises a core rod and a sleeve sleeved on the outside of the core rod; the core rod comprises a potassium-doped core layer and a potassium-fluorine co-doped core layer successively arranged from the inside to the outside; the sleeve comprises an inner sleeve and an outer sleeve successively arranged from the inside to the outside; the inner sleeve comprises a deep fluorine-doped layer and a shallow fluorine-doped layer successively arranged from the inside to the outside; and a gap between the core rod and the inner sleeve forms a first space. The present invention is capable of solving attenuation caused by high interface stress against an ultra-low attenuation optical fiber, and fabricating the ultra-low attenuation optical fiber.

[LUO, Wenyong, MAO, Qian, XIANG, Haipeng, GENG, Hao, QIAN, Feng, CHEN, Baoping, HUANG, Zhiling, HUANG, Fei, HU, Guyue, QI, Qingqing] No. 6 High-Tech 4 Road East Lake High-Tech Zone Wuhan, Hubei 430000, CN A multiband attenuation flattened fiber, comprising a central gradient core layer (1), a flattened core layer (2), a transition core layer (3), a flattened suppression cladding layer (4), and a quartz cladding layer (5) which are sequentially arranged from inside to outside in a radial direction. The refractive index of the central gradient core layer (1) is less than the refractive index of the flattened core layer (2), the refractive index of the flattened core layer (2) is greater than the refractive index of the transition core layer (3), and the refractive index of the transition core layer (3) is greater than the refractive index of the flattened suppression cladding layer (4); from inside to outside in the radial direction, a relative refractive index difference of the central gradient core layer (1) is increased in a first polynomial line shape, and a relative refractive index difference of the transition core layer (3) is decreased in a second polynomial line shape; the central gradient core layer (1), the flattened core layer (2) and the flattened suppression cladding layer (4) are doped with germanium, or the central gradient core layer (1) and the flattened suppression cladding layer (4) are doped with fluorine, thereby solving the problem of large multiband attenuation flatness in the related art.＜img id="iaf01" file="imgaf001.tif" wi="132" he="101" img-content="drawing" img-format="tif" /＞

[LUO, Wenyong 罗文勇, MAO, Qian 毛谦, XIANG, Haipeng 项海鹏, GENG, Hao 耿皓, QIAN, Feng 钱峰, CHEN, Baoping 陈保平, HUANG, Zhiling 黄志凌, HUANG, Fei 黄非, HU, Guyue 胡古月, QI, Qingqing 祁庆庆] No.6 High-tech 4 Road, East Lake High-tech Zone 中国湖北省武汉市东湖高新技术开发区高新四路6号, Hubei 430000Wuhan, Hubei 430000;Building 1 & 2, Guandong Science and Technology 中国湖北省武汉市东湖开发区关东科技园1、2号楼, Hubei 430000Park, East Lake Development ZoneWuhan, Hubei 430000;No.77, Zhongxinke Road, Gaolan Port Economic Zone 中国广东省珠海市高栏港经济区中信科路77号, Guangdong 519050Zhuhai, Guangdong 519050 A multiband attenuation flattened fiber, comprising a central gradient core layer (1), a flattened core layer (2), a transition core layer (3), a flattened suppression cladding layer (4), and a quartz cladding layer (5) which are sequentially arranged from inside to outside in a radial direction. The refractive index of the central gradient core layer (1) is less than the refractive index of the flattened core layer (2), the refractive index of the flattened core layer (2) is greater than the refractive index of the transition core layer (3), and the refractive index of the transition core layer (3) is greater than the refractive index of the flattened suppression cladding layer (4); from inside to outside in the radial direction, a relative refractive index difference of the central gradient core layer (1) is increased in a first polynomial line shape, and a relative refractive index difference of the transition core layer (3) is decreased in a second polynomial line shape; the central gradient core layer (1), the flattened core layer (2) and the flattened suppression cladding layer (4) are doped with germanium, or the central gradient core layer (1) and the flattened suppression cladding layer (4) are doped with fluorine, thereby solving the problem of large multiband attenuation flatness in the related art. A multiband attenuation flattened fiber, comprising a central gradient core layer (1), a flattened core layer (2), a transition core layer (3), a flattened suppression cladding layer (4), and a quartz cladding layer (5) which are sequentially arranged from inside to outside in a radial direction. The refractive index of the central gradient core layer (1) is less than the refractive index of the flattened core layer (2), the refractive index of the flattened core layer (2) is greater than the refractive index of the transition core layer (3), and the refractive index of the transition core layer (3) is greater than the refractive index of the flattened suppression cladding layer (4); from inside to outside in the radial direction, a relative refractive index difference of the central gradient core layer (1) is increased in a first polynomial line shape, and a relative refractive index difference of the transition core layer (3) is decreased in a second polynomial line shape; the central gradient core layer (1), the flattened core layer (2) and the flattened suppression cladding layer (4) are doped with germanium, or the central gradient core layer (1) and the flattened suppression cladding layer (4) are doped with fluorine, thereby solving the problem of large multiband attenuation flatness in the related art.

[CUI, Dongming 崔东明, KONG, Ming 孔明, WU, Shujian 伍淑坚] No.6 High-tech 4 Road, East Lake High-tech Zone 中国湖北省武汉市东湖高新技术开发区高新四路6号, Hubei 430000Wuhan, Hubei 430000;North Lake Industrial Park, Wuhan Chemical Industry Park 中国湖北省武汉市武汉化学工业区北湖产业园, Hubei 430085Wuhan, Hubei 430085 The present application relates to a sintering device and a sintering method for an optical fiber preform soot body. The sintering device comprises a sintering box, a furnace core tube, a heating assembly, a lead rod, a preform feeding mechanism, a first pipe group, and a second pipe group. The furnace core tube and the heating assembly are arranged in the sintering box, the heating assembly forming a heating zone. The lead rod extends into the furnace core tube and is used to connect a preform soot body. The preform feeding mechanism is connected to the lead rod to drive the lead rod to move so that the preform soot body is heated in the heating zone. The first pipe group runs through the walls of the sintering box and the furnace core tube and communicates with an inner cavity of the furnace core tube, and comprises a first intake pipe and a first exhaust pipe. The second pipe group runs through the wall of the sintering box and communicates with an internal cavity of the sintering box, and comprises a second intake pipe and a second exhaust pipe. The present application integrates dehydroxylation, vitrification sintering, and deuteration, and can effectively eliminate a residual gas inside an optical fiber preform, reduce the amount of He used, and eliminate structural defects from the source of optical fiber preform manufacturing, thereby reducing the hydrogen sensitivity of an optical fiber. The present application relates to a sintering device and a sintering method for an optical fiber preform soot body. The sintering device comprises a sintering box, a furnace core tube, a heating assembly, a lead rod, a preform feeding mechanism, a first pipe group, and a second pipe group. The furnace core tube and the heating assembly are arranged in the sintering box, the heating assembly forming a heating zone. The lead rod extends into the furnace core tube and is used to connect a preform soot body. The preform feeding mechanism is connected to the lead rod to drive the lead rod to move so that the preform soot body is heated in the heating zone. The first pipe group runs through the walls of the sintering box and the furnace core tube and communicates with an inner cavity of the furnace core tube, and comprises a first intake pipe and a first exhaust pipe. The second pipe group runs through the wall of the sintering box and communicate

[LUO, Wenyong, ZHAO, Zisen, QI, Wei, KE, Yili, DU, Cheng, ZHANG, Tao, WANG, Bi] No.6 High-Tech 4 Road East Lake High-Tech Zone, Wuhan, Hubei 430000, CN

[LUO, Wenyong, CHEN, Baoping, KE, Yili, DU, Cheng, ZHANG, Tao, LI, Wei, SHAO, Shuai, ZHU, Qiao, ZENG, Fanqiu] CN,Wuhan, Hubei 430000,No.6 High-Tech 4 Road East Lake High-Tech Zone;CN,Wuhan, Hubei 430074,No. 42 Optics Valley Chuangye Street;

[LUO, Wenyong, ZHAO, Zisen, QI, Wei, KE, Yili, DU, Cheng, ZHANG, Tao, WANG, Bi] No.6 High-Tech 4 Road East Lake High-Tech Zone, Wuhan, Hubei 430000, CN Disclosed in the present invention is a polarization maintaining optical fiber, which relates to the field of optical fibers. The polarization maintaining optical fiber comprises, in order from the inside to the outside, a fiber core, a quartz cladding layer, an inner coating layer and an outer coating layer. The quartz cladding layer is located at the periphery of the fiber core, two stress zones are provided between the quartz cladding layer and the fiber core, and the two stress zones are symmetrically distributed along the center of the fiber core. The fiber core comprises, in order from the inside to the outside, a circular central core region and at least one annular region concentrically arranged with the central core region, and the refractive indexes of the central core region and the annular region are different. The inner coating layer and the outer coating layer are both of a double-layer structure, and the modulus of each of the inner coating layer and the outer coating layer is different, and the modulus from the inside to the outside increases sequentially. The polarization maintaining optical fiber provided by the present invention provides more stable and higher crosstalk output and optical fiber attenuation performances.＜img id="iaf01" file="imgaf001.tif" wi="45" he="54" img-content="drawing" img-format="tif" /＞

[LUO, Wenyong, CHEN, Baoping, KE, Yili, DU, Cheng, ZHANG, Tao, LI, Wei, SHAO, Shuai, ZHU, Qiao, ZENG, Fanqiu] No.6 High-Tech 4 Road East Lake High-Tech Zone, Wuhan, Hubei 430000, CN Disclosed is a PANDA polarization maintaining optical fiber, comprising a core layer (1) and quartz cladding (2), wherein two stress regions (3), which are centrosymmetric along the core layer (1), are provided in the quartz cladding (2), and transition annular regions (4), which are concentric with the stress regions (3), are provided outside the stress regions (3); the core layer (1) comprises a germanium-doped core layer (10) and a fluorine-doped core layer (11) successively arranged from the inside to the outside; the germanium-doped core layer (10) comprises a flat germanium-doped layer (100) and a gradient germanium-doped layer (101) successively arranged from the inside to the outside; the refractive index profile of the gradient germanium-doped layer (101) is of a parabolic shape, and the refractive index of the gradient germanium-doped layer (101) gradually decreases in a direction away from the flat germanium-doped layer (100); the fluorine-doped core layer (11) comprises a quartz core layer (110), a first gradient fluorine-doped layer (111), a flat fluorine-doped layer (112) and a second gradient fluorine-doped layer (113) successively arranged from the inside to the outside; the refractive index profiles of the first gradient fluorine-doped layer (111) and the second gradient fluorine-doped layer (113) are both in the shape of a curve, and are symmetric along the refractive index profile of the flat fluorine-doped layer (112); and the refractive index of the first gradient fluorine-doped layer (111) gradually decreases in a direction away from the quartz core layer (110). The cut-off wavelength of the polarization maintaining optical fiber is less than 830 nm. The PANDA polarization maintaining optical fiber is applicable to multiple bands and has a good attenuation and a good extinction ratio.＜img id="iaf01" file="imgaf001.tif" wi="153" he="67" img-content="drawing" img-format="tif" /＞