Method for manufacturing a glass core preform for optical fibres

    公开(公告)号:US10934205B2

    公开(公告)日:2021-03-02

    申请号:US15765830

    申请日:2015-10-09

    Abstract: A method of manufacturing a glass core preform for optical fibres including providing a porous soot core preform having a central longitudinal hole extending axially therethrough and an a/b ratio of from 0.20 to 0.40; simultaneously dehydrating and doping with fluorine the soot core preform at a temperature of from 1000° C. to 1350° C. by exposing it to an atmosphere containing a chlorine-containing gas and a fluorine-containing gas, the content of the fluorine-containing gas in the atmosphere being of from 0.01% to 0.50% by volume, and simultaneously consolidating the soot core preform and closing the central longitudinal hole by exposing the soot core preform to an atmosphere substantially devoid of fluorine and of chlorine at a consolidation temperature of from 1500° C. to 1650° C., while reducing the pressure down the central hole, thereby forming a glass core preform.

    METHOD OF MANUFACTURING PREFORMS FOR OPTICAL FIBRES HAVING LOW WATER PEAK
    2.
    发明申请
    METHOD OF MANUFACTURING PREFORMS FOR OPTICAL FIBRES HAVING LOW WATER PEAK 有权
    制造具有低水峰值的光纤的预制件的方法

    公开(公告)号:US20150336840A1

    公开(公告)日:2015-11-26

    申请号:US14758018

    申请日:2012-12-28

    Abstract: A method of manufacturing an optical fibre preform comprising: providing a glass core rod comprising a central core region of radius a and an inner clad region of external radius b to define a first core-to-clad ratio a/b; forming an intermediate glass preform comprising an intermediate clad region surrounding the inner clad region of the glass rod and having an external radius c to define a second core-to-clad ratio a/c, and overcladding the intermediate glass preform by forming an overclad region surrounding the intermediate clad region to form an optical fibre preform, wherein the first core-to-clad ratio a/b is equal to or less than 0.40 and the second core-to-clad ratio a/c is of from 0.20 to 0.25.

    Abstract translation: 一种制造光纤预制件的方法,包括:提供包括半径为a的中心芯区域和外部半径b的内部包层区域的玻璃芯棒,以限定第一芯包层比a / b; 形成中间玻璃预制件,其包括围绕所述玻璃棒的内包层区的中间包层区,并具有外半径c以限定第二芯包层比a / c,并且通过形成外包层区域来包覆所述中间玻璃预制件 围绕中间包层区以形成光纤预制件,其中第一芯包层比a / b等于或小于0.40,第二芯包层比a / c为0.20至0.25。

    Method for detecting defects in a rod-shaped transparent object

    公开(公告)号:US09939390B2

    公开(公告)日:2018-04-10

    申请号:US14899840

    申请日:2013-06-25

    Abstract: A method for inspecting defects inside a rod-shaped transparent object by using a scanning beam of parallel light rays directed onto a rod-shaped transparent object orthogonally to the longitudinal axis of the object so that an inspection plane comprises an object's cross-section. The scanning beam is detected at an opposite side of the rod-shaped object that is interposed to intercept the parallel rays of the scanning beam. The electric output signal from the detector is processed to produce a first light intensity profile in a first scan direction, the light intensity profile comprising a shadow region delimited by first and second shadow edges, which is indicative of the outside diameter of the object across the inspection plane. The method comprises analyzing the first light intensity profile to determine the presence or absence of a peak of positive intensity within the shadow region and, if an intensity peak is determined to be present, to determine the presence or absence of a region of depressed intensity within the intensity peak. If, as a result of analyzing, an intensity peak within the shadow region is determined to be absent or a region of depressed intensity is determined to be present within the intensity peak, the presence of at least one structural defect within the object's cross-section is identified. In the preferred embodiments, the rod-shaped transparent object is a glass core rod for the production of a transmission optical fiber.

    Method of manufacturing preforms for optical fibres having low water peak
    4.
    发明授权
    Method of manufacturing preforms for optical fibres having low water peak 有权
    具有低水峰的光纤预成型件的制造方法

    公开(公告)号:US09416045B2

    公开(公告)日:2016-08-16

    申请号:US14758018

    申请日:2012-12-28

    Abstract: A method of manufacturing an optical fibre preform comprising: providing a glass core rod comprising a central core region of radius a and an inner clad region of external radius b to define a first core-to-clad ratio a/b; forming an intermediate glass preform comprising an intermediate clad region surrounding the inner clad region of the glass rod and having an external radius c to define a second core-to-clad ratio a/c, and overcladding the intermediate glass preform by forming an overclad region surrounding the intermediate clad region to form an optical fibre preform, wherein the first core-to-clad ratio a/b is equal to or less than 0.40 and the second core-to-clad ratio a/c is of from 0.20 to 0.25.

    Abstract translation: 一种制造光纤预制件的方法,包括:提供包括半径为a的中心芯区域和外部半径b的内部包层区域的玻璃芯棒,以限定第一芯包层比a / b; 形成中间玻璃预制件,其包括围绕所述玻璃棒的内包层区的中间包层区,并具有外半径c以限定第二芯包层比a / c,并且通过形成外包层区域来包覆所述中间玻璃预制件 围绕中间包层区以形成光纤预制件,其中第一芯包层比a / b等于或小于0.40,第二芯包层比a / c为0.20至0.25。

    Method for manufacturing a preform for optical fibers

    公开(公告)号:US11780762B2

    公开(公告)日:2023-10-10

    申请号:US16081244

    申请日:2016-03-03

    Abstract: The present invention relates to a method for manufacturing a preform for optical fibers, which method comprises the sequential steps of: i) deposition of non-vitrified silica layers on the inner surface of a hollow substrate tube; ii) deposition of vitrified silica layers inside the hollow substrate tube on the inner surface of the non-vitrified silica layers deposited in step i); iii) removal of the hollow substrate tube from the vitrified silica layers deposited in step ii) and the non-vitrified silica layers deposited in step i) to obtain a deposited tube; iv) optional collapsing said deposited tube obtained in step iii) to obtain a deposited rod comprising from the periphery to the center at least one inner optical cladding and an optical core; v) preparation of an intermediate layer by the steps of: * deposition of non-vitrified silica layers on the outside surface of the deposited tube obtained in step iii) or deposited rod obtained in step iv) with a flame hydrolysis process in an outer reaction zone using glass-forming precursors, and subsequently; * drying and consolidating said non-vitrified silica layers into a vitrified fluorine-doped silica intermediate cladding layer; and * in case preceding step iv) was omitted collapsing; to provide a solid rod comprising from the periphery to the center the intermediate layer, at least one inner optical cladding and an optical core; wherein a fluorine-comprising gas is used during the deposition and/or drying and/or consolidating and wherein the intermediate layer has a ratio between the outer diameter of the intermediate cladding layer (C) to the outer diameter of the optical core (A) that is at least 3.5; vi) deposition of natural silica on the outside surface of the intermediate cladding layer of the solid rod obtained in step v) by melting natural silica particles in an outer deposition zone to produce an outer cladding whereby a preform is obtained.

    METHOD FOR MANUFACTURING A GLASS CORE PREFORM FOR OPTICAL FIBRES

    公开(公告)号:US20180282199A1

    公开(公告)日:2018-10-04

    申请号:US15765830

    申请日:2015-10-09

    Abstract: A method of manufacturing a glass core preform for optical fibres including providing a porous soot core preform having a central longitudinal hole extending axially therethrough and an a/b ratio of from 0.20 to 0.40; simultaneously dehydrating and doping with fluorine the soot core preform at a temperature of from 1000° C. to 1350° C. by exposing it to an atmosphere containing a chlorine-containing gas and a fluorine-containing gas, the content of the fluorine-containing gas in the atmosphere being of from 0.01% to 0.50% by volume, and simultaneously consolidating the soot core preform and closing the central longitudinal hole by exposing the soot core preform to an atmosphere substantially devoid of fluorine and of chlorine at a consolidation temperature of from 1500° C. to 1650° C., while reducing the pressure down the central hole, thereby forming a glass core preform.

    METHOD FOR DETECTING DEFECTS IN A ROD-SHAPED TRANSPARENT OBJECT
    8.
    发明申请
    METHOD FOR DETECTING DEFECTS IN A ROD-SHAPED TRANSPARENT OBJECT 有权
    检测锯齿形透明物体缺陷的方法

    公开(公告)号:US20160139062A1

    公开(公告)日:2016-05-19

    申请号:US14899840

    申请日:2013-06-25

    Abstract: A method for inspecting defects inside a rod-shaped transparent object by using a scanning beam of parallel light rays directed onto a rod-shaped transparent object orthogonally to the longitudinal axis of the object so that an inspection plane comprises an object's cross-section. The scanning beam is detected at an opposite side of the rod-shaped object that is interposed to intercept the parallel rays of the scanning beam. The electric output signal from the detector is processed to produce a first light intensity profile in a first scan direction, the light intensity profile comprising a shadow region delimited by first and second shadow edges, which is indicative of the outside diameter of the object across the inspection plane. The method comprises analysing the first light intensity profile to determine the presence or absence of a peak of positive intensity within the shadow region and, if an intensity peak is determined to be present, to determine the presence or absence of a region of depressed intensity within the intensity peak. If, as a result of analysing, an intensity peak within the shadow region is determined to be absent or a region of depressed intensity is determined to be present within the intensity peak, the presence of at least one structural defect within the object's cross-section is identified. In the preferred embodiments, the rod-shaped transparent object is a glass core rod for the production of a transmission optical fibre.

    Abstract translation: 一种用于通过使用与物体的纵向轴线正交的杆状透明物体上的平行光线的扫描光束来检查棒状透明物体内的缺陷的方法,使得检查平面包括物体的横截面。 扫描光束在被插入以截取扫描光束的平行光线的棒状物体的相反侧被检测。 来自检测器的电输出信号被处理以在第一扫描方向上产生第一光强度分布,光强度分布包括由第一和第二阴影边界限定的阴影区域,该阴影区域指示物体的外直径 检查机。 该方法包括分析第一光强分布以确定阴影区域内正强度峰值的存在或不存在,以及如果确定强度峰值存在,则确定强度峰值存在或不存在 强度峰值。 如果作为分析的结果,确定阴影区域内的强度峰值被确定为不存在,或者确定强度峰值区域存在于强度峰值内,则在物体的横截面内存在至少一个结构缺陷 被识别。 在优选实施例中,棒状透明物体是用于制造透射光纤的玻璃芯棒。

    A METHOD FOR MANUFACTURING A PREFORM FOR OPTICAL FIBERS

    公开(公告)号:US20190084865A1

    公开(公告)日:2019-03-21

    申请号:US16081244

    申请日:2016-03-03

    Abstract: The present invention relates to a method for manufacturing a preform for optical fibers, which method comprises the sequential steps of: i) deposition of non-vitrified silica layers on the inner surface of a hollow substrate tube; ii) deposition of vitrified silica layers inside the hollow substrate tube on the inner surface of the non-vitrified silica layers deposited in step i); iii) removal of the hollow substrate tube from the vitrified silica layers deposited in step ii) and the non-vitrified silica layers deposited in step i) to obtain a deposited tube; iv) optional collapsing said deposited tube obtained in step iii) to obtain a deposited rod comprising from the periphery to the center at least one inner optical cladding and an optical core; v) preparation of an intermediate layer by the steps of: *deposition of non-vitrified silica layers on the outside surface of the deposited tube obtained in step iii) or deposited rod obtained in step iv) with a flame hydrolysis process in an outer reaction zone using glass-forming precursors, and subsequently; *drying and consolidating said non-vitrified silica layers into a vitrified fluorine-doped silica intermediate cladding layer; and *in case preceding step iv) was omitted collapsing; to C provide a solid rod comprising from the periphery to the center the intermediate layer, at least one inner optical cladding and an optical core; wherein a fluorine-comprising gas is used during the deposition and/or drying and/or consolidating and wherein the intermediate layer has a ratio between the outer diameter of the intermediate cladding layer (C) to the outer diameter of the optical core (A) that is at least 3.5; vi) deposition of natural silica on the outside surface of the intermediate cladding layer of the solid rod obtained in step v) by melting natural silica particles in an outer deposition zone to produce an outer cladding whereby a preform is obtained.

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