Anti-resonance hollow-core optical fiber

Abstract

The invention relates to an anti-resonant hollow-core fiber (1000) comprising a fiber longitudinal axis (2300) and a fiber core radius RFast (2310), a fiber cladding (2000) having a cladding inner bore (2200), a plurality of anti-resonant cells (3000), each anti-resonant cell comprising an ARU outer cell (3100) and an ARU inner cell (3400), wherein the arcuately designed ARU outer unit (3100) and the arcuately designed ARU inner unit (3400) are connected to each other along two seam lines (3700, 3700 ') such that the ARU inner unit (3400) projects at least partially into a first interior (3170) of the ARU outer unit (3100), and wherein the anti-resonant units (3000) are arranged at a target location on the cladding inner side (2150) at a distance from each other and are not in contact with each other, in the at least one anti-resonance unit (3000), the ARU arc unit (3900) is arranged in the first inner portion (3170), the ARU arc unit (3900) is circularly designed and has a radius FBR (3920), and the ARU arc unit (3900) is connected to the ARU inner unit (3400) along a contact seam (3730). According to the invention, the following (I) ratio of two times of the radius FBR (3920) suitable for the ARU arcuate unit to the fiber core radius RFast (2310) is provided: (I);

Description

Background Technology

[0001] This invention relates to an anti-resonant hollow optical fiber.

[0002] Existing technology

[0003] Hollow-core optical fiber has a core, which comprises a evacuated cavity filled with gas or liquid. In hollow-core fiber, the interaction between light and glass is weaker than in solid-core fiber. The refractive index of the core is lower than that of the surrounding cladding, making total internal reflection impossible. Depending on the physical mechanism of light transmission, hollow-core optical fiber is classified into "photonic bandgap fiber" and "anti-resonant reflection fiber".

[0004] In a variant of hollow fiber known as “anti-resonant hollow fiber” (ARHCF), the hollow core region is surrounded by an inner cladding region in which so-called anti-resonant units (also called “anti-resonant elements” or “ARUs”) are arranged. The walls of the anti-resonant units, which are uniformly distributed around the hollow core, can act as Fabry-Perot cavities operating in anti-resonance mode, reflecting incident light and thus realizing waveguides in the fiber core.

[0005] This technology ensures hollow-core optical fibers with low optical attenuation, a very wide transmission spectrum (also in the UV or IR wavelength range), and low latency during data transmission.

[0006] WO 2022157179 A1 discloses an anti-resonant hollow-core optical fiber, wherein the hollow core is surrounded by an inner cladding having anti-resonant units. These anti-resonant units have an ARU outer element and an ARU inner element inserted into the ARU outer element. Furthermore, arcuate elements can be arranged within the non-resonant elements. However, it has been found that, due to the design of the arcuate elements, the transmission characteristics of the fundamental mode and higher-order modes are unsuitable for applications, especially in the telecommunications field. In this regard, reference is made to application WO2022157179A1, the contents of which are incorporated herein by reference.

[0007] Technical issues

[0008] For industrial applications, low-attenuation antiresonant hollow fiber is required. Furthermore, it needs to be easily and mass-producible. This is the only way to keep the cost of antiresonant hollow fiber within reasonable limits. It is worth noting that antiresonant hollow fiber that yields good results on a laboratory scale may not be suitable for large-scale use.

[0009] The purpose of this invention is to provide an anti-resonant hollow fiber that overcomes the above-mentioned shortcomings.

[0010] The object of this invention is to provide an anti-resonant hollow fiber that can be produced precisely and repeatedly, and also exhibits low attenuation.

[0011] Specifically, one object of the present invention is to provide an anti-resonant hollow fiber with particularly low waveguide loss.

[0012] Specifically, one object of the present invention is to provide an anti-resonant hollow fiber that effectively attenuates higher-order modes.

[0013] Preferred embodiments of the present invention

[0014] The features of the independent claim contribute to at least partial fulfillment of at least one of the foregoing objectives. The dependent claims provide preferred embodiment variations that facilitate at least partial fulfillment of at least one of the objectives.

[0015] The following variations of the implementation scheme contribute at least in part to achieving at least one of the aforementioned objectives:

[0016] I1.I A first embodiment variation of an anti-resonant hollow-core optical fiber, the anti-resonant hollow-core optical fiber comprising a longitudinal axis of the fiber and a core radius R_Faser, a fiber cladding with an inner hole, and multiple anti-resonant units.

[0017] Each anti-resonant unit includes an ARU outer unit and an ARU inner unit.

[0018] • The arc-shaped outer ARU unit and the arc-shaped inner ARU unit are connected to each other along two seam lines, such that the inner ARU unit at least partially protrudes into the first internal space of the outer ARU unit.

[0019] The anti-resonant units are spaced apart from each other at the target location on the inner side of the cladding and are arranged so that they do not contact each other.

[0020] The ARU outer element has a first circle radius FA_R and a first central angle FA_MW.

[0021] • The ARU internal element has a second circular radius FI_R and a second central angle FI_MW, wherein the deviation between the first circular radius FA_R and the second circular radius FI_R is less than 10% of the first circular radius FA_R.

[0022] in

[0023] • The first central angle FA_MW is less than 345° and greater than 275°, and

[0024] • The second central angle FI_MW is less than 195° and greater than 40°.

[0025] In at least one anti-resonant unit,

[0026] • The ARU arc-shaped unit is arranged in the first internal space.

[0027] • The ARU arc-shaped element is circular.

[0028] • It has a radius FB_R, and

[0029] • The ARU arc-shaped unit is connected to the ARU inner unit along the contact joint.

[0030] This variant of the implementation scheme is characterized by the following fact: for the ratio of twice the radius FB_R of the ARU arc unit to the fiber core radius R_Faser, the following applies.

[0031]

[0032] I2.I Another embodiment of the anti-resonant hollow-core optical fiber with the characteristics of the first embodiment variant is characterized in that, for the ratio of twice the radius FB_R of the ARU arc unit to the fiber core radius R_Faser, the following applies:

[0033] • 2*FB_R / R_Faser is greater than or equal to 0.8, especially greater than or equal to 0.9, especially greater than or equal to 1.0; and

[0034] • 2*FB_R / R_Faser is less than or equal to 1.6, especially less than or equal to 1.5, especially less than or equal to 1.45.

[0035] I3.I Another embodiment of the antiresonant hollow-core optical fiber having the features of the first or second embodiment variant is characterized in that the antiresonant unit has an optical fiber spatial height FH_Z1, and the following applies to the ratio of the optical fiber spatial height FH_Z1 to the optical fiber core radius R_Faser:

[0036]

[0037] Another embodiment variation of the antiresonant hollow-core optical fiber with the features of the third embodiment is characterized in that, for the ratio of the fiber spatial height FH_Z1 to the fiber core radius R_Faser, the following applies:

[0038] • FH_Z1 / R_Faser is greater than or equal to 0.8, especially greater than or equal to 0.85, especially greater than or equal to 0.9, especially greater than or equal to 0.95, especially greater than or equal to 1.0, and

[0039] • FH_Z1 / R_Faser is less than or equal to 1.4, especially less than or equal to 1.35, especially less than or equal to 1.3, especially less than or equal to 1.2.

[0040] I5.I Another embodiment of the anti-resonant hollow-core optical fiber having any of the features of the aforementioned variant is characterized in that, for the ratio of the fiber spatial height FH_Z1 to twice the radius FB_R of the ARU arcuate unit, the following applies:

[0041] Especially ≤1.3.

[0042] Another embodiment of the anti-resonant hollow-core optical fiber with features of the fifth embodiment variant is characterized in that, for the ratio of the fiber spatial height FH_Z1 to twice the radius FB_R of the ARU arcuate unit, the following applies:

[0043] • FH_Z1 / (2*FB_R) is less than or equal to 1.2, especially less than or equal to 1.05, especially less than or equal to 1.0, especially less than or equal to 0.9, especially less than or equal to 0.85, especially less than or equal to 0.8; and

[0044] ·FH_Z1 / (2*FB_R) is greater than or equal to 0.1, especially greater than or equal to 0.125, especially greater than or equal to 0.15, especially greater than or equal to 0.2, especially greater than or equal to 0.4, especially greater than or equal to 0.5.

[0045] I7.I Another embodiment of the anti-resonant hollow fiber having any of the aforementioned embodiments is characterized in that each anti-resonant unit has an ARU arcuate unit arranged in a first internal space of each ARU outer unit.

[0046] Another embodiment of the anti-resonant hollow-core optical fiber having any of the features of the aforementioned embodiment variant is characterized in that the deviation between the first circular radius FA_R and the second circular radius FI_R is less than 5% of the first circular radius FA_R, particularly less than 3%, particularly less than 2%, particularly less than 1%.

[0047] Another embodiment of the anti-resonant hollow fiber having any of the features of the aforementioned embodiment variant is characterized in that the anti-resonant hollow fiber has three, four, five, six, seven or eight anti-resonant units, and in particular, the anti-resonant hollow fiber has an odd number of anti-resonant units.

[0048] Another embodiment of the anti-resonant hollow fiber having any of the features of the aforementioned embodiment variant is characterized in that the anti-resonant units are asymmetrically arranged on the inner surface of the cladding.

[0049] Another embodiment of the anti-resonant hollow-core optical fiber having any of the features of the aforementioned variant of the embodiment is characterized in that at least one anti-resonant unit has at least one of the following features:

[0050] • The outer unit and / or inner unit and / or curved unit of the ARU include an amorphous solid body, particularly glass, especially quartz glass.

[0051] • The outer unit and / or inner unit and / or curved unit of the ARU are composed of an amorphous solid body, particularly glass, especially quartz glass.

[0052] The outer ARU unit and / or the inner ARU unit and / or the curved ARU unit are made of the same material, particularly comprising or composed of glass having a refractive index of at least 1.4, particularly 1.4 to 3, particularly 1.4 to 2.8, and

[0053] The wall thicknesses of the ARU outer element, ARU inner element, and ARU arc element are basically the same.

[0054] Another embodiment of the antiresonant hollow fiber having any of the features of the aforementioned variant is characterized in that, with all other design parameters remaining the same, the waveguide loss of the antiresonant hollow fiber is at least 50 times less than that of the antiresonant hollow fiber without arc units.

[0055] I13.I Another embodiment of the anti-resonant hollow-core optical fiber having any of the features of the aforementioned variant of the embodiment is characterized in that the anti-resonant hollow-core optical fiber has at least one of the following features:

[0056] For transmission wavelengths between 1.0 μm and 2.5 μm, the basic attenuation is less than 1.0 dB / km, particularly less than 0.5 dB / km, particularly less than 0.25 dB / km, and particularly less than 0.15 dB / km.

[0057] • For transmission wavelengths up to 0.8 μm, the basic attenuation is less than 1 dB / km.

[0058] Another embodiment of the antiresonant hollow fiber having any of the features of the aforementioned variant is characterized in that the difference between the fundamental attenuation of the straight antiresonant hollow fiber and the antiresonant hollow fiber wound to a diameter of 10 mm is less than two orders of magnitude, particularly less than one order of magnitude, particularly less than half an order of magnitude.

[0059] I15.I Another embodiment of the anti-resonant hollow-core optical fiber having any of the features of the aforementioned embodiment variant is characterized in that, for the first circular radius FA_R and / or the second circular radius FI_R, the following applies:

[0060] • The radius of the first circle and / or the radius of the second circle are less than 30 μm, particularly less than 20 μm, particularly less than 17.5 μm, particularly less than or equal to 16.5 μm, particularly less than or equal to 15.75 μm, and / or

[0061] • The radius of the first circle and / or the radius of the second circle is greater than 5 μm, especially greater than 10 μm, especially greater than or equal to 11.5 μm, especially greater than or equal to 12.25 μm.

[0062] I16.I Another embodiment of the antiresonant hollow-core optical fiber having any of the features of the aforementioned variant of the embodiment is characterized in that at least one ARU arcuate unit has at least one of the following features:

[0063] The radius FB_R of the ARU arc element is less than 15 μm, especially less than 12.5 μm, especially less than 11 μm, and especially less than 9.5 μm.

[0064] • The radius FB_R of the ARU arc element is greater than 0.75 μm, especially greater than 1 μm, and especially greater than 2.5 μm.

[0065] I17.I Another embodiment of the antiresonant hollow-core optical fiber having any of the features of the aforementioned variant of the embodiment is characterized in that at least one ARU arcuate unit has at least one of the following features:

[0066] The radius of the first circle, FA_R, is less than 25 μm, especially less than 15 μm.

[0067] • The radius of the first circle FA_R is greater than 5μm, especially greater than 7μm.

[0068] • The radius of the first circle, FA_R, is less than or equal to 16.5 μm, and in particular less than or equal to 15.75 μm.

[0069] • The radius of the first circle, FA_R, is greater than or equal to 11.5 μm, and in particular greater than or equal to 12.25 μm.

[0070] • The first central angle FA_MW is less than 345°, especially less than 340°; especially less than 320°, especially less than 310°.

[0071] • The first central angle FA_MW is greater than 220°, especially greater than 250°, especially greater than 270°, especially greater than 280°.

[0072] I18.I Another embodiment of the antiresonant hollow-core optical fiber having any of the features of the aforementioned variant of the embodiment is characterized in that at least one ARU inner unit has at least one of the following features:

[0073] The radius of the second circle, FI_R, is less than 25 μm, especially less than 15 μm.

[0074] • The radius FI_R of the second circle is greater than 5 μm, especially greater than 7 μm.

[0075] • The radius FI_R of the second circle is less than or equal to 16.5 μm, and in particular less than or equal to 15.75 μm.

[0076] • The radius FI_R of the second circle is greater than or equal to 11.5 μm, and in particular greater than or equal to 12.25 μm.

[0077] • The second central angle FI_MW is less than 130°, especially less than 120°, and especially less than 100°; and

[0078] • The second central angle FI_MW is greater than 40°, especially greater than 50°.

[0079] I19.I Another embodiment of the antiresonant hollow-core optical fiber having any of the features of the aforementioned variant of the embodiment is characterized in that at least one antiresonant unit has at least one of the following features:

[0080] The wall thickness of the ARU outer unit and / or ARU inner unit and / or ARU arc-shaped unit is between 0.1 μm and 2.5 μm, particularly between 0.15 μm and 1.5 μm, particularly between 0.25 μm and 0.75 μm, particularly between 0.35 μm and 0.65 μm, and particularly 0.5 μm.

[0081] • For a signal wavelength of 1,550 nm within the first transmission window, the wall thickness of the ARU outer cell and / or ARU inner cell and / or ARU arc cell is between 0.35 μm and 0.65 μm, particularly between 0.4 μm and 0.6 μm, and especially 0.5 μm.

[0082] • For a signal wavelength of 1,550 nm in the second transmission window, the wall thickness of the ARU outer cell and / or ARU inner cell and / or ARU arc cell is between 0.75 μm and 1.25 μm, particularly between 0.9 μm and 1.1 μm, and especially 1 μm. Detailed Implementation

[0083] Some of the characteristics described are associated with the term "substantially". The term "substantially" should be understood in such a way that, under actual conditions and manufacturing techniques, the precise mathematical interpretation of terms such as "overlapping", "perpendicular", "diameter", or "parallel" may never be given precisely, but only within certain manufacturing tolerances. For example, "substantially parallel axes" form an angle of -5 to 5 degrees relative to each other, and "substantially equal volumes" includes a variation of at most 5% by volume. For example, "devices composed substantially of quartz glass" includes a quartz glass content of ≥95% by weight to ≤100% by weight. Furthermore, "substantially perpendicular" includes an angle of 85 to 95 degrees. Further explanation of the term "substantially" is provided below for some characteristics.

[0084] The above objective is achieved, at least in part, by an anti-resonant hollow-core fiber comprising a fiber longitudinal axis and a fiber core radius R_Faser, a fiber cladding with cladding holes, and multiple anti-resonant units.

[0085] Each anti-resonant unit includes an ARU outer unit and an ARU inner unit.

[0086] • The arc-shaped outer ARU unit and the arc-shaped inner ARU unit are connected to each other along two seam lines, such that the inner ARU unit at least partially protrudes into the first internal space of the outer ARU unit.

[0087] The anti-resonant units are spaced apart from each other at the target location on the inner side of the cladding and are arranged so that they do not contact each other.

[0088] The ARU outer element has a first circle radius FA_R and a first central angle FA_MW.

[0089] The ARU internal element has a second circle radius FI_R and a second central angle FI_MW.

[0090] The deviation between the radius of the first circle FA_R and the radius of the second circle FI_R is less than 10% of the radius of the first circle FA_R.

[0091] • The first central angle FA_MW is less than 345° and greater than 275°, and

[0092] • The second central angle FI_MW is less than 195° and greater than 40°.

[0093] In at least one anti-resonant unit,

[0094] • The ARU arc-shaped unit is arranged in the first internal space.

[0095] • The ARU arc-shaped element is circular.

[0096] • It has a radius FB_R, and

[0097] • The ARU arc-shaped unit is connected to the ARU inner unit along the contact joint.

[0098] According to the present invention, the following applies to the ratio of twice the radius FB_R of the ARU arc unit to the fiber core radius R_Faser:

[0099]

[0100] Twice the radius FB_R of the ARU arc cell corresponds to the diameter of the ARU arc cell. This type of antiresonant hollow fiber exhibits improved fundamental mode over shorter travel distances because the higher-order modes in the core are coupled particularly effectively with the high-loss modes in the ARU arc cell.

[0101] "Fundamental mode" should be understood as meaning that the fundamental mode has more than 95% of the power transmitted in the fiber core, especially more than 97.7%. In this respect, the rapid realization of the fundamental mode is equivalent to the attenuation of higher-order modes operating in the fiber core to a certain extent over short travel distances, especially less than 20m, especially less than 10m, and especially less than 5m, so that more than 95% of the power transmitted in the fiber core can be obtained in the fundamental mode, especially more than 97.7%.

[0102] Generally speaking, antiresonant hollow-core fiber (hereinafter referred to as ARHCF) has a silica sheath and an air-filled cladding cavity (also known as an air core), which forms a special light propagation mechanism. ARHCF follows the optical transmission mechanism of antiresonant reflective waveguide (ARROW), rather than the total internal reflection principle of single-mode fiber (SMF).

[0103] The ARROW light propagation mechanism utilizes coherent reflection at the air-silica interface, typically combined with an arrangement of anti-resonant units around a central hollow core, to effectively confine and guide forward-propagating light within the core. To represent light propagation in an ARROW CF in a simulation, a hollow capillary with a regular silica cladding is chosen as a representative to describe the anti-resonance theory. A hollow capillary with a regular annular cladding can be considered a Fabry-Perot resonator in the radial direction. This Fabry-Perot resonator allows optical frequencies that do not resonate with the core wall to be transmitted within the fiber core. These optical frequencies are reflected back into the fiber core, where they propagate with low loss. On the other hand, optical resonant frequencies cannot be confined within the fiber core and escape radially into the cladding region.

[0104] The loss of ARHCF mainly consists of scattering loss and waveguide loss:

[0105] Scattering loss is mainly divided into material scattering loss and surface scattering loss in all components.

[0106] Surface scattering loss is caused by factors such as the surface roughness of the cladding inner holes and the outer unit of the ARU. These surface roughnesses are significantly affected by thermodynamic processes during optical fiber production.

[0107] Material loss occurs in every region of the ARHCF. This includes not only the hollow core but also the glass region. Furthermore, the coating surrounding the silica cladding also has an impact.

[0108] ○ Scattering loss is largely independent of the design chosen for ARHCF.

[0109] Waveguide loss is caused by factors such as the arrangement of anti-resonant elements around the central hollow core.

[0110] The transmission range of ARHCF is spectrally defined by the anti-resonant region of the irregular cladding. The combination of anti-resonance and suppression of coupling between the core mode and the sheath mode is crucial to the optical transmission principle of ARHCF.

[0111] For example, the coupling between different modules significantly affects the use of ARHCF in data centers. Consider the following modules for the following description and / or simulation:

[0112] ·The base model in the core

[0113] Also known as the core base mold;

[0114] ·High-order mode in the core

[0115] Also known as a high-order core mold (HOM),

[0116] • In the simulation, only the second-order mode (i.e., the first-order mode above the fundamental mode) was considered;

[0117] ·Modules in ARU external units

[0118] Also known as the anti-resonant unit mode or ARU mode,

[0119] • In the simulation, only the fundamental mode in the external element of the ARU was considered;

[0120] ·Module in ARU arc unit

[0121] Also known as the arc-shaped unit module or DNE module

[0122] • In the simulation, only the fundamental mode in the ARU arc element was considered.

[0123] Surprisingly, it was found that the geometry of the ARU arc cell significantly affects the conduction behavior of the ARHCF. Using the dimensions of the ARU arc cell, phase matching can be achieved between the higher-order modes in the core and those in the ARU arc cell. This effect is desirable and allows the higher-order modes in the core to couple with the more lossy arc cell modes. In addition to the inherent waveguide losses, the resulting loss mechanism also attenuates the higher-order modes in the core, enabling the ARHCF to operate effectively with the core fundamental mode.

[0124] Both the outer and inner ARU units are arc-shaped. The deviations of the outer and / or inner ARU unit walls from the ideal arc shape are specifically based on manufacturing-related variations. In particular, the deviations of the first circular radius FA_R and / or the second circular radius FI_R from the average first circular radius FA_R and / or the average second circular radius FI_R may not exceed 10%, particularly not more than 5%, and especially not more than 2.5%, particularly at the azimuth angles on the arc (thus producing an elliptical path) and at different points along the ARHCF axis.

[0125] The ARU arc element is circular. The deviation of the radius FB_R of the ARU arc element from the ideal circular shape is specifically based on manufacturing-related variations. In particular, the deviation of the radius FB_R of the ARU arc element from the average radius FB_R of the ARU arc element can not exceed 10%, especially not exceed 5%, especially not exceed 2.5%, particularly at azimuth angles on the circle (thus producing an elliptical path) and at different points along the ARHCF axis.

[0126] Another embodiment variation is characterized in that the fiber core radius R_Faser is less than 30 μm, particularly less than 25 μm, and especially less than 20 μm. Another embodiment variation is characterized in that the fiber core radius is greater than 5 μm, particularly greater than 10 μm, and especially greater than 15 μm. Specifically, the antiresonant hollow fiber can have a fiber core radius R_Faser of 17.25 μm. The listed fiber core radii R_Faser represent advantageous embodiment variations, provided that:

[0127] The waveguide loss of the fundamental mode in the core decreases with increasing first circle radius FA_R, but...

[0128] The bending sensitivity of ARHCF increases significantly with the increase of the first circle radius FA_R.

[0129] Therefore, the listed fiber core radius R_Faser enables ARHCF to exhibit both low waveguide loss in the fundamental mode and good bending sensitivity.

[0130] Another variant of the implementation scheme is characterized by the following fact: for the ratio of twice the radius FB_R of the ARU arc unit to the fiber core radius R_Faser, the following applies:

[0131] • 2*FB_R / R_Faser is greater than or equal to 0.8, especially greater than or equal to 0.9, especially greater than or equal to 1.0; and

[0132] • 2*FB_R / R_Faser is less than or equal to 1.6, especially less than or equal to 1.5, especially less than or equal to 1.45.

[0133] This type of anti-resonant hollow fiber has a particularly short travel distance until the fundamental mode is reached.

[0134] Another variant of the implementation is characterized in that the anti-resonant unit has an optical fiber spatial height FH_Z1, and the following applies to the ratio of the optical fiber spatial height FH_Z1 to the optical fiber core radius R_Faser:

[0135]

[0136] Surprisingly, it was found that the geometry of the ARU curved unit significantly affects the conduction behavior of the ARHCF compared to the geometry of the ARU outer unit. In an ARHCF with at least one anti-resonant unit having specified parameters, the higher-order modes in the core are coupled particularly effectively with the ARU mode and / or the DNE mode. Consequently, the higher-order modes in the core are attenuated, and the hollow fiber is in the fundamental mode over a shorter travel distance.

[0137] Another variant of the implementation scheme is characterized by the following fact: for the ratio of fiber spatial height FH_Z1 to fiber core radius R_Faser, the following applies:

[0138] • FH_Z1 / R_Faser is greater than or equal to 0.8, especially greater than or equal to 0.85, especially greater than or equal to 0.9, especially greater than or equal to 0.95, especially greater than or equal to 1.0, and

[0139] • FH_Z1 / R_Faser is less than or equal to 1.4, especially less than or equal to 1.35, especially less than or equal to 1.3, especially less than or equal to 1.2.

[0140] The specified range allows for further optimization of the coupling between higher-order modes in the core and ARU and / or DNE modes. This further shortens the travel distance of the hollow fiber into the fundamental mode.

[0141] Surprisingly, it was found that the geometry of the ARU arc unit affects not only the fundamental mode but also the attenuation of the ARHCF. Another implementation variation is characterized by the fact that for a ratio of fiber spatial height FH_Z1 to twice the radius FB_R of the ARU arc unit, the following applies:

[0142] Especially ≤1.3.

[0143] The radius FB_R of the ARU arc element corresponds to twice the diameter of the ARU arc element. This variant of the implementation is characterized by particularly low attenuation of the fundamental mode.

[0144] Another variant of the implementation is characterized by the fact that, for a ratio of fiber spatial height FH_Z1 to twice the radius FB_R of the ARU arcuate unit, the following applies:

[0145] • FH_Z1 / (2*FB_R) is less than or equal to 1.2, especially less than or equal to 1.05, especially less than or equal to 1.0, especially less than or equal to 0.9, especially less than or equal to 0.85, especially less than or equal to 0.8; and

[0146] ·FH_Z1 / (2*FB_R) is greater than or equal to 0.1, especially greater than or equal to 0.125, especially greater than or equal to 0.15, especially greater than or equal to 0.2, especially greater than or equal to 0.4, especially greater than or equal to 0.5.

[0147] The specified interval allows for further optimization of the fundamental mode attenuation.

[0148] Another variant of the implementation is characterized in that each anti-resonant unit has an ARU arc-shaped unit arranged in the first internal space of each ARU outer unit. Using an ARU arc-shaped unit in each anti-resonant unit of the hollow fiber improves the coupling between higher-order modes and DNE modes in the core.

[0149] Another variant of this embodiment is characterized in that the deviation between the first circular radius FA_R and the second circular radius FI_R is less than 5% of the first circular radius FA_R, particularly less than 3%, particularly less than 2%, and particularly less than 1%. Reducing the deviation between the first circular radius FA_R of the ARU outer unit and the second circular radius FI_R of the ARU inner unit is complex due to manufacturing reasons. Tubes meeting these requirements, especially those made of quartz glass, can only be produced through efficient and precise thermal processes. This variant of the embodiment further reduces scattering losses in the ARHCF.

[0150] Another variant of the implementation is characterized by having three, four, five, six, seven, or eight anti-resonant elements in the anti-resonant hollow fiber, particularly an odd number of anti-resonant elements. This implementation allows for further optimization of the fundamental mode attenuation.

[0151] Another variant of the implementation is characterized by an asymmetric arrangement of anti-resonant units on the inner surface area of ​​the cladding. Consequently, higher-order modes in the core are attenuated, and the hollow-core fiber remains in fundamental mode over a shorter travel distance.

[0152] Another variant of the embodiment is characterized in that at least one of the anti-resonant units has at least one of the following characteristics:

[0153] • The outer unit and / or inner unit and / or curved unit of the ARU include an amorphous solid body, particularly glass, especially quartz glass.

[0154] • The outer unit and / or inner unit and / or curved unit of the ARU are composed of an amorphous solid body, particularly glass, especially quartz glass.

[0155] The outer ARU unit and / or the inner ARU unit and / or the curved ARU unit are made of the same material, particularly comprising or composed of glass having a refractive index of at least 1.4, particularly 1.4 to 3, particularly 1.4 to 2.8, and

[0156] The wall thicknesses of the ARU outer element, ARU inner element, and ARU arc element are basically the same.

[0157] These variants of the anti-resonant unit are optimized for low-loss signal transmission at wavelengths between 1.0 μm and 2.5 μm.

[0158] Another variant of the implementation scheme is characterized in that the waveguide loss of the antiresonant hollow fiber is at least 50 times less than that of the antiresonant hollow fiber without the arc unit, while all other design parameters remain the same. The ARU arc unit described in the variant of the implementation scheme makes the following possible:

[0159] • The coupling between the fundamental mode in the core and the ARU and / or DNE modes is minimal, but at the same time...

[0160] • The higher-order modes in the core are effectively coupled with the more lossy ARU and DNE modes.

[0161] This results in an ARHCF that, on the one hand, enters the fundamental mode over a short travel distance, and on the other hand, has only the low attenuation of the fundamental mode.

[0162] Another embodiment is characterized in that the anti-resonant hollow fiber has at least one of the following characteristics:

[0163] For transmission wavelengths between 1.0 μm and 2.5 μm, the basic attenuation is less than 1.0 dB / km, particularly less than 0.5 dB / km, particularly less than 0.25 dB / km, and particularly less than 0.15 dB / km.

[0164] • For transmission wavelengths up to 0.8 μm, the basic attenuation is less than 1 dB / km.

[0165] Due to the low attenuation of the fundamental mode, this implementation variant of ARHCF is particularly suitable for data centers.

[0166] Another variant of the implementation is characterized in that the fundamental attenuation difference between the straight antiresonant hollow fiber and the antiresonant hollow fiber wound to a diameter of 10 mm is less than two orders of magnitude, particularly less than one order of magnitude, and particularly less than half an order of magnitude.

[0167] Another variant of the implementation scheme is characterized by the following, for the radius FA_R of the first circle:

[0168] • This radius is less than 30 μm, especially less than 20 μm, especially less than 17.5 μm, especially less than or equal to 16.5 μm, especially less than or equal to 15.75 μm, and / or

[0169] • This radius is greater than 5 μm, especially greater than 10 μm, especially greater than or equal to 11.5 μm, especially greater than or equal to 12.25 μm.

[0170] This results in an ARHCF that has only low attenuation of the fundamental mode.

[0171] Another embodiment variation is characterized in that at least one ARU external unit has at least one of the following features:

[0172] The radius of the first circle, FA_R, is less than 25 μm, especially less than 15 μm.

[0173] • The radius of the first circle FA_R is greater than 5μm, especially greater than 7μm.

[0174] • The radius of the first circle, FA_R, is less than or equal to 16.5 mm, and in particular less than or equal to 15.75 mm.

[0175] • The radius of the first circle, FA_R, is greater than or equal to 11.5 μm, and in particular greater than or equal to 12.25 μm.

[0176] • The first central angle FA_MW is less than 345°, especially less than 340°; especially less than 320°, especially less than 310°.

[0177] • The first central angle FA_MW is greater than 220°, especially greater than 250°, especially greater than 270°, especially greater than 280°.

[0178] This results in an ARHCF that, on the one hand, becomes the fundamental mode over short travel distances, and on the other hand, has only the low attenuation of the fundamental mode.

[0179] Another embodiment variation is characterized in that at least one internal unit of the ARU has at least one of the following features:

[0180] The radius of the second circle, FI_R, is less than 25 μm, especially less than 15 μm.

[0181] • The radius FI_R of the second circle is greater than 5 μm, especially greater than 7 μm.

[0182] • The radius FI_R of the second circle is less than or equal to 16.5 μm, and in particular less than or equal to 15.75 μm.

[0183] • The radius FI_R of the second circle is greater than or equal to 11.5 μm, and in particular greater than or equal to 12.25 μm.

[0184] • The second central angle FI_MW is less than 130°, especially less than 120°, and especially less than 100°; and

[0185] • The second central angle FI_MW is greater than 40°, especially greater than 50°.

[0186] This results in an ARHCF that, on the one hand, becomes the fundamental mode over short travel distances, and on the other hand, has only the low attenuation of the fundamental mode.

[0187] Another embodiment variation is characterized in that at least one ARU arcuate unit has at least one of the following features:

[0188] ·

[0189] The radius FB_R of the ARU arc element is less than 15 μm, especially less than 12.5 μm, especially less than 11 μm, and especially less than 9.5 μm.

[0190] • The radius FB_R of the ARU arc element is greater than 0.75 μm, especially greater than 1 μm, and especially greater than 2.5 μm.

[0191] This results in an ARHCF that becomes the fundamental mode over short travel distances.

[0192] Another variant of the embodiment is characterized in that at least one of the anti-resonant units has at least one of the following characteristics:

[0193] The wall thickness of the ARU outer unit and / or ARU inner unit and / or ARU arc-shaped unit is between 0.1 μm and 2.5 μm, particularly between 0.15 μm and 1.5 μm, particularly between 0.25 μm and 0.75 μm, particularly between 0.35 μm and 0.65 μm, and particularly 0.5 μm.

[0194] • For a signal wavelength of 1,550 nm within the first transmission window, the wall thickness of the ARU outer cell and / or ARU inner cell and / or ARU arc cell is between 0.35 μm and 0.65 μm, particularly between 0.4 μm and 0.6 μm, and especially 0.5 μm.

[0195] • For a signal wavelength of 1,550 nm in the second transmission window, the wall thickness of the ARU outer cell and / or ARU inner cell and / or ARU arc cell is between 0.75 μm and 1.25 μm, particularly between 0.9 μm and 1.1 μm, and especially 1 μm.

[0196] For ARHCFs that specifically include ARU arc units with a specified wall thickness, and particularly for transmission wavelengths between 1.0 μm and 2.5 μm, the higher-order modes in the core are coupled particularly effectively with the more lossy DNE modes. Therefore, the higher-order modes in the core are attenuated, and the hollow-core fiber is in the fundamental mode over a shorter travel distance.

[0197] The features and characteristics disclosed in the specification may be necessary for various embodiments of the claimed invention (individually and in any combination of each other).

[0198] The invention is further illustrated by the following examples with the aid of the accompanying drawings. The invention is not limited to the drawings.

[0199] Attached Figure

[0200] It is shown that:

[0201] Figure 1 An arc-shaped ARU external unit is shown.

[0202] Figure 2 The arc-shaped internal cell of the ARU is shown.

[0203] Figure 3 The circular ARU arc-shaped cell is shown.

[0204] Figure 4 This shows a portion of the anti-resonant unit and magnified details of the seam line.

[0205] Figure 5 Enlarged details of the anti-resonant unit and contact seam are shown.

[0206] Figure 6 The image shows a cross-section through a portion of an anti-resonant hollow fiber.

[0207] Figure 7 The cross-section through an anti-resonant hollow fiber is shown.

[0208] Figure 8 A graph showing the ratio of the effective mode exponent Δneff (DNE) to twice the radius FB_R of the ARU arc cell and the fiber core radius R_Faser is presented.

[0209] Figure 9 A graph showing the ratio of the effective mode exponent Δneff (ARU) to the fiber spatial height FH_Z1 and the fiber core radius R_Faser is presented.

[0210] Figure 10 A graph showing the waveguide loss difference between the fundamental and higher-order modes in the core is presented as a ratio of the fiber spatial height FH_Z1 to the fiber core radius R_Faser.

[0211] Figure 11 A graph showing the waveguide loss of the fundamental mode as a function of the ratio of the fiber spatial height FH_Z1 to twice the radius FB_R of the ARU arc cell is presented.

[0212] Figure 12 Another graph shows the ratio of the effective mode exponent Δneff (DNE) to twice the radius FB_R of the ARU arc cell and the fiber core radius R_Faser.

[0213] Figure 1 A cross-section through the ARU outer unit 3100 is shown. The ARU outer unit 3100 is a tubular structure with an arc-shaped cross-section. The ARU outer unit 3100 extends along the longitudinal axis 3110 of the first body. Figure 1 Therefore, the ARU external unit 3100 extends into the drawing plane.

[0214] The ARU outer unit 3100 has an ARU outer unit wall 3150. In particular, the ARU outer unit wall 3150 may contain or be composed of a material that is transparent to the working light of the optical fiber (e.g., glass, especially doped or undoped quartz glass (SiO2)).

[0215] In one implementation variation, the ARU outer unit wall 3150 has a wall thickness between 0.25 μm and 0.75 μm, particularly between 0.35 μm and 0.65 μm, and particularly 0.5 μm.

[0216] As Figure 1 As illustrated in the cross-section, the ARU outer unit 3100 has an arcuate cross-section. In the context of this invention, the term "arc" refers to a portion of a circular line. Two points on a circle divide the circular line into two arcs. In the context of this invention, an element is described as "arc-shaped" when its outer shape follows the trajectory of one of the two arcs. To illustrate this, the first circle 2980... Figure 1 The first circle 2980 is drawn in the middle. It is divided into two arcs by two intersecting lines QQ and RR. The cross section of the ARU outer element 3100 follows one of the two arcs.

[0217] Furthermore, draw the intersecting line PP, which extends through the two points where the intersecting lines QQ and RR intersect circle 2980. The first chord of the ARU outer element 3100 is the distance located on the intersecting line PP and defined by the intersecting lines QQ and RR. The first chord length 3290 is the length of the first chord.

[0218] The ARU outer unit 3100 has a first circular radius FA_R 3200. This first circular radius FA_R 3200 describes the distance between the ARU outer unit wall 3150 and the first body longitudinal axis 3110.

[0219] The ARU outer element 3100 has a first segment height 3280. This first segment height 3280 describes the length of a straight line perpendicular to the first chord and extending to the apex of the ARU outer element wall 3150.

[0220] The ARU outer element 3100 has a first central angle FA_MW 3250. This first central angle FA_MW 3250 describes the angle at which its vertex is located at the center of the first circle 2980 and its side intersects the boundary point of the arc (here, the point where the first circle 2980 intersects the intersecting lines QQ and RR). A complete circle has a degree value of 360°. Since the ARU outer element 3100 is arc-shaped, the first central angle FA_MW 325 is less than 360°.

[0221] The ARU outer unit 3100 has a first internal space 3170 defined by the ARU outer unit wall 3150 and a first chord.

[0222] In one implementation variation, the ARU external unit 3100 may have at least one of the following features:

[0223] The radius of the first circle, FA_R 3200, is less than 25 μm, especially less than 15 μm.

[0224] • The radius of the first circle, FA_R 3200, is greater than 5 μm, especially greater than 7 μm.

[0225] • The radius of the first circle, FA_R 3200, is less than or equal to 16.5 μm, and in particular less than or equal to 15.75 μm.

[0226] • The radius of the first circle, FA_R 3200, is greater than or equal to 11.5 μm, and in particular greater than or equal to 12.25 μm.

[0227] • The first central angle 3250FA_MW is less than 345°, especially less than 340°; especially less than 320°, especially less than 310°.

[0228] • The first central angle 3250FA_MW is greater than 220°, especially greater than 250°, especially greater than 270°, especially greater than 280°.

[0229] Figure 2 A cross-section through the ARU inner unit 3400 is shown. The ARU inner unit 3400 is a tubular structure with an arc-shaped cross-section. The ARU inner unit 3400 extends along the longitudinal axis 3410 of the second body. Figure 2 Therefore, the ARU inner cell 3400 extends into the drawing plane.

[0230] The ARU inner cell 3400 has an ARU inner cell wall 3450. Specifically, the ARU inner cell wall 3450 may comprise or be composed of a material that is transparent to the working light of the optical fiber (e.g., glass, particularly doped or undoped silica glass (SiO2)). In one embodiment variation, the ARU inner cell wall 3450 has a wall thickness between 0.25 μm and 0.75 μm, particularly between 0.35 μm and 0.65 μm, and especially 0.5 μm.

[0231] The ARU inner cell 3400 has an arc-shaped cross-section. To illustrate this, the second circle 2990 is... Figure 2 The second circle 2990 is drawn in the middle. It is divided into two arcs by two intersecting lines HH and II. The cross-section of the inner element 3400 of the ARU follows one of the two arcs.

[0232] Furthermore, draw the intersection line GG, which extends through the two intersection lines HH and II and intersects the second circle 2990 at the two points. The second chord of the ARU inner unit 3400 is the extension located on the intersection line GG and defined by the intersection lines HH and II. The second chord length 3590 is the length of the second chord.

[0233] The ARU inner cell 3400 has a second segment height 3580. This second segment height 3580 describes the length of a straight line perpendicular to the second chord and extending to the apex of the ARU inner cell wall 3450.

[0234] Furthermore, the ARU inner cell 3400 has a second circular radius FI_R 3500. This second circular radius FI_R 3500 describes the distance between the ARU inner cell wall 3450 and the second body longitudinal axis 3410.

[0235] The ARU inner element 3400 has a second central angle FI_MW 3550. This second central angle FI_MW 3550 describes the angle at which its vertex is located at the center of the second circle 2990 and its side intersects the boundary point of the arc (here, the point where the second circle 2990 intersects with the intersecting lines HH and II). A complete circle has a degree value of 360°. Since the ARU inner element 3400 is arc-shaped, the second central angle FI_MW 3550 is less than 360°.

[0236] The ARU inner unit 3400 has a second internal space 3470 defined by the ARU inner unit wall 3450 and the second chord.

[0237] Figure 1 and Figure 2 Cross-sections, namely the axial plan view of the ARU outer unit 3100 and the ARU inner unit 3400, are shown. In the two-dimensional view of each of the shown main body longitudinal axes 3110 and 3410, the ARU outer unit 3100 and the ARU inner unit 3400 have arc-shaped cross-sections, which correspond to tubular structural elements in the three-dimensional view.

[0238] The arcs of the ARU outer unit 3100 and / or the ARU inner unit 3400 are substantially circular, wherein, in particular, the first circular radius FA_R 3200 and / or the second circular radius FI_R 3500 fluctuate by no more than 10% on the circumference of the ARU outer unit 3100 and / or the ARU inner unit 3400, preferably no more than 5%, more preferably no more than 3%.

[0239] In one implementation variation, the ARU internal unit 3400 may have at least one of the following characteristics:

[0240] The radius of the second circle, FI_R 3500, is less than 25 μm, especially less than 15 μm.

[0241] • The radius of the second circle, FI_R 3500, is greater than 5 μm, especially greater than 7 μm.

[0242] • The radius of the second circle, FI_R 3500, is less than or equal to 16.5 μm, and particularly less than or equal to 15.75 μm.

[0243] • The radius of the second circle, FI_R 3500, is greater than or equal to 11.5 μm, and particularly greater than or equal to 12.25 μm.

[0244] • The second central angle FI_MW 3550 is less than 130°, especially less than 120°, especially less than 100°; and

[0245] • The second central angle FI_MW 3550 is greater than 40°, especially greater than 50°.

[0246] Figure 3 An ARU arcuate unit 3900, which is a tubular structure, is shown. The ARU arcuate unit 3900 extends along the longitudinal axis 3910 of the third body. Figure 3 In this case, the ARU arc element 3900 extends into the drawing plane.

[0247] The ARU arc-shaped unit 3900 has an arc-shaped wall 3950. In particular, the arc-shaped wall 3950 may contain or be composed of a material that is transparent to the working light of the optical fiber (e.g., glass, especially doped or undoped quartz glass (SiO2)).

[0248] In one implementation variation, the curved wall 3950 has a wall thickness between 0.25 μm and 0.75 μm, particularly between 0.35 μm and 0.65 μm, and particularly 0.5 μm.

[0249] The ARU arcuate unit 3900 has a radius FB_R 3920. This radius FB_R 3920 describes the distance between the arcuate wall 3950 and the longitudinal axis 3910 of the first body. The ARU arcuate unit 3900 has a third internal space 3970 defined by the arcuate wall 3950.

[0250] In one implementation variation, the ARU arc-shaped unit 3900 may have at least one of the following features:

[0251] The radius of the ARU arc element FB_R 3920 is less than 15 μm, especially less than 12.5 μm, especially less than 11 μm, and especially less than 9.5 μm.

[0252] The radius of the ARU arc element FB_R 3920 is greater than 0.75 μm, and especially greater than 1 μm.

[0253] Especially those larger than 2.5μm.

[0254] Figure 4 It shows including, for example Figure 1 and Figure 2 The diagram shows portions of the hollow optical fibers of the ARU outer unit 3100 and ARU inner unit 3400. The ARU outer unit 3100 has a first internal space 3170 defined at least partially by the ARU outer unit wall 3150. The arcuate ARU inner unit 3400 protrudes at least partially into the first internal space 3170. This means that, in cross-section, the ARU inner unit 3400 extends substantially above the first chord of the ARU outer unit 3100.

[0255] The arc-shaped ARU outer unit 3100 and the arc-shaped ARU inner unit 3400 are connected to each other along two connecting seams 3700, 3700' arranged substantially parallel to the longitudinal axis 3110 of the first main body. In particular, this connection can be achieved through a thermal process.

[0256] To illustrate this, the area surrounding the connecting seam 3700 is... Figure 4 The image is enlarged in size. This connection is formed between the following two:

[0257] • The first endpoint of the ARU outer unit wall 3150 of the ARU outer unit 3100, and

[0258] • The second endpoint of the ARU inner cell wall 3450 of the ARU inner cell 3400.

[0259] because Figure 4 The cross-section is shown, so that the two connecting seams 3700, 3700' in the three-dimensional hollow fiber 1000 extend into the drawing plane.

[0260] Due to manufacturing-related changes, it is possible that, particularly in some areas, the first end point of the ARU outer unit wall 3150 may not precisely coincide with the second end point of the ARU inner unit wall to form connection seams 3700, 3700'. Specifically, due to manufacturing-related changes, two deviations in this positioning of the ARU inner unit 3400 may occur:

[0261] 1. The first endpoint (particularly its region) of the outer unit wall 3150 of the ARU can be arranged on the inner unit wall 3450 of the inner unit 3400 of the ARU, and the inner unit 3400 can therefore partially protrude from the first internal space 3170. In this case, the inner unit 3400 can only be partially integrally bonded to the inner surface 2150 of the cladding 2000. The latter can depend on the proportion of the second central angle FI_MW protruding from the first internal space 3170. In particular, in cross-section, no more than 5%, particularly no more than 2.5%, particularly no more than 1%, of the second central angle FI_MW 3550 of the inner unit 3400 can protrude from the first internal space 3170. The smaller the proportion of the second central angle FI_MW 3550 protruding from the first internal space 3170, the better the fundamental model of the ARHCF.

[0262] 2. The second endpoint (particularly its region) of the inner unit wall 3450 of the ARU can be arranged on the outer unit wall 3150 of the outer unit 3100 of the ARU, thus completely mounting the inner unit 3400 within the first internal space 3170. In this case, the outer unit 3100 of the ARU can only be partially integrally bonded to the inner surface 2150 of the cladding 2000. The latter depends on the proportion of the second central angle FI_MW 3550, which is theoretically required to establish contact between the first and second endpoints. In particular, in the cross-section, no more than 5%, particularly no more than 2.5%, particularly no more than 1%, of the second central angle FI_MW 3550 may be required to theoretically establish contact between the first and second endpoints. The smaller the required proportion of the second central angle FI_MW 3550, the better the fundamental model of the ARHCF.

[0263] Figure 5 An anti-resonant unit 3000 is shown, which includes, for example... Figure 2 The arc-shaped ARU outer unit 3100 and arc-shaped ARU inner unit 3400 shown are composed of, as... Figure 3 The ARU arc element 3900 is shown as a supplement. The ARU arc element 3900 is used as an anti-resonant element to reduce the attenuation of the fundamental mode and / or waveguide loss, and if designed properly, it can also increase the attenuation of higher modes in the core.

[0264] The arc-shaped ARU inner unit 3400 and the ARU arc-shaped unit 3900 are connected to each other along a contact line 3730 arranged substantially parallel to the longitudinal axis 3110 of the first body. Specifically, this connection can be achieved through a thermal process. In one embodiment variation, the contact line 3730 is arranged on the ARU inner unit 3400 such that the distance between the contact line 3730 and the first chord is maximized.

[0265] The ARU outer unit 3100 has a first internal space 3170 defined at least partially by the ARU outer unit wall 3150. The ARU arcuate unit 3900 is arranged in the first internal space 3170.

[0266] like Figure 5 As illustrated, the anti-resonant unit 3000 has an optical fiber space height FH_Z1 3800. This optical fiber space height FH_Z1 3800 describes the shortest length of a straight line extending between the vertices of the ARU outer unit 3100 and the ARU arcuate unit 3900. In one embodiment variation, the optical fiber space height FH_Z1 3800 may be perpendicular to the first chord and extend to the vertices of the ARU outer unit wall 3150. The optical fiber space height FH_Z1 3800 describes the free space between the ARU outer unit 3100 and the ARU arcuate unit 3900.

[0267] The three main longitudinal axes of the ARU outer unit 3100, ARU inner unit 3400, and ARU arcuate unit 3900 can be substantially located on a straight line 3750. The lateral deviation of each of the main longitudinal axes from the straight line 3750 is specifically limited by manufacturing-related tolerances; in particular, this deviation is less than 5% of the first circle radius FA_R, especially less than 2.5% of the first circle radius FA_R, and especially less than 1% of the first circle radius FA_R.

[0268] To illustrate this, the area surrounding the connecting seam 3730 is... Figure 5 The image is enlarged in size. This connection is formed between the following two:

[0269] • Points on the ARU inner cell wall 3450 of the ARU inner cell 3400, and

[0270] • Point on the arc wall 3950 of the ARU arc unit 3900.

[0271] because Figure 5 The cross-section is shown, so the contact seam 3730 in the three-dimensional anti-resonant unit 3000 extends into the drawing plane.

[0272] Figure 6A cross-section through a portion of the anti-resonant hollow fiber 1000 is shown. The portion of the anti-resonant hollow fiber 1000 between the two crossing lines AA and BB is shown. The anti-resonant hollow fiber 2400 has a cladding 2000. The cladding 2000 can be constructed from a combination of an elongated sheath and an elongated cladding material. Since the cladding material and sheath material are the same in the illustrated embodiment variant, the transition between the two materials is not obvious. The cladding 2000 has an inner cladding radius 2250 generated by the distance between the longitudinal axis 2300 of the anti-resonant hollow fiber 1000 and the inner surface 2150. Anti-resonant elements 3000 are arranged on the inner surface 2150 and integrally bonded to the inner surface 2150 of the cladding 2000.

[0273] Both the outer ARU unit 3100 and the inner ARU unit 3400 are arc-shaped. The deviations of the outer ARU unit wall 3150 and / or the inner ARU unit wall 3450 from the ideal arc shape are specifically based on manufacturing-related variations. In particular, the deviations of the first circle radius FA_R 3200 and / or the second circle radius FI_R 3500 in the ARHCF from the average first circle radius FA_R 3200 and / or the average second circle radius FI_R 3500 may not exceed 10%, particularly not more than 5%, and especially not more than 2.5%, particularly at the azimuth angle on the arc (thus producing an elliptical path) and at different points along the axial direction of the ARHCF.

[0274] The ARU arc element 3900 is circular. The deviation of the radius FB_R3920 of the ARU arc element 3900 from the ideal circular shape is specifically based on manufacturing-related variations. In particular, the deviation of the radius FB_R3920 of the ARU arc element 3900 from the average radius FB_R3920 of the ARU arc element 3900 may not exceed 10%, particularly not more than 5%, and especially not more than 2.5%, particularly at azimuth angles on the circle (thus producing an elliptical path) and at different points along the ARHCF axis.

[0275] Figure 7 A cross-section through an anti-resonant hollow fiber 1000 is shown. The anti-resonant hollow fiber 1000 has a hollow core 2470. Electromagnetic waves can propagate through the hollow core 2470. The hollow fiber 1000 has a core radius 2310 generated by the shortest distance between the longitudinal axis 2300 of the anti-resonant hollow fiber 1000 and the ARU outer unit 3100. Figure 7 An arrangement of multiple anti-resonant elements 3000 (also referred to as ARUs) on the inner surface 2150 defining the hollow core 2470 is illustrated. In one embodiment, the anti-resonant hollow fiber 1000 may have three, four, five, six, seven, or eight anti-resonant elements 3000. Figure 7In this embodiment, the anti-resonant hollow fiber 1000 has six anti-resonant units 3000. In this variant, the anti-resonant units 3000 are asymmetrically arranged on the inner surface 2150 of the cladding 2000.

[0276] Figure 7 The anti-resonant hollow fiber 1000 shown is characterized in that the deviation between the first circular radius FA_R 3200 and the second circular radius FI_R 3500 is less than 10% of the first circular radius FA_R 3200.

[0277] exist Figure 7 In the antiresonant hollow fiber 1000 shown, the ARU outer unit 3100 and / or ARU inner unit 3400 and / or ARU curved unit 3900 may contain quartz glass or be composed of quartz glass. Furthermore, the wall thickness of the ARU outer unit 3100 and / or ARU inner unit 3400 and / or ARU curved unit 3900 can be designed based on the wavelength transmitted in the ARHCF. Therefore, for a signal wavelength of 1,550 nm, the wall thickness of the ARU outer unit 3100 and / or ARU inner unit 3400 and / or ARU curved unit 3900 of the antiresonant hollow fiber 1000 can be between 0.35 μm and 0.65 μm, particularly between 0.4 μm and 0.6 μm. If the anti-resonant hollow fiber 1000 is to operate at a signal wavelength of 1,550 nm in the second transmission window, the wall thickness of the ARU outer unit 3100 and / or ARU inner unit 3400 and / or ARU arc unit 3900 can be between 1.25 μm and 0.75 μm, particularly between 1.1 μm and 0.9 μm.

[0278] Specifically, the wall thicknesses of the ARU outer unit 3100, ARU inner unit 3400, and ARU arc-shaped unit 3900 can be substantially the same. Specifically, the wall thicknesses of the ARU outer unit 3100, ARU inner unit 3400, and ARU arc-shaped unit 3900 can differ from the wall thickness of the ARU outer unit 3100 by less than 10%, and particularly less than 5%.

[0279] Figure 7 The antiresonant hollow-core fiber 1000 shown can be further characterized in that the fiber core radius R_Faser2310 is less than 30 μm, particularly less than 25 μm, and especially less than 20 μm. Furthermore, the antiresonant hollow-core fiber 1000 can be characterized in that the fiber core radius R_Faser 2310 is greater than 5 μm, particularly greater than 10 μm, and especially greater than 15 μm. Specifically, the antiresonant hollow-core fiber 1000 can have a fiber core radius R_Faser 2310 of 17.25 μm.

[0280] In a variant of the anti-resonant hollow fiber 1000 implementation, the first circular radius FA_R 3200 can be less than or equal to 15.75 μm and greater than or equal to 12.25 μm.

[0281] Figure 7 Several parameters are illustrated to describe the arrangement of some geometries of the anti-resonant hollow fiber 1000:

[0282] The diameter of the ARU arc element 3980 is FB_D 3900, which is twice the radius of the ARU arc element 3920, FB_R 3900.

[0283] • The fiber space height FH_Z1 3800 of the anti-resonant unit 3000 describes the shortest distance between the vertices of the ARU outer unit 3100 and the ARU arc unit 3900, and

[0284] • The core radius 2310 of the anti-resonant hollow fiber 1000 describes the shortest distance between the longitudinal axis 2300 and the ARU outer unit 3100.

[0285] Figures 8 to 12 Simulation results for an antiresonant hollow fiber 1000 with ARU arcuate units are presented. Numerical calculations were performed using the finite element method COMSOL Mode Solver. A perfectly matched layer (PML) with a thickness of 10 μm was implemented at the outer interface of the fiber to study the radiation characteristics of the waveguide structure by absorbing radially emitted light energy.

[0286] The simulation begins with anti-resonant hollow fiber 1000, whose structure is similar to... Figure 7 The anti-resonant hollow-core fiber 1000 is shown. This anti-resonant hollow-core fiber 1000 includes an fiber cladding 2000 having a core radius R_Faser2310. Furthermore, the anti-resonant hollow-core fiber 1000 includes six anti-resonant elements 3000.

[0287] Each anti-resonant unit includes an ARU outer unit 3100 and an ARU inner unit 3400.

[0288] • The arc-shaped ARU outer unit 3100 and the arc-shaped ARU inner unit 3400 are connected to each other along two seam lines 3700, 3700', such that the ARU inner unit 3400 at least partially protrudes into the first internal space 3170 of the ARU outer unit 3100.

[0289] In each anti-resonant unit of anti-resonant unit 3000

[0290] • The ARU arc-shaped unit 3900 is arranged in the first internal space 3170, wherein

[0291] The ARU arc-shaped unit 3900 is circular, and

[0292] • The ARU arc-shaped unit 3900 is connected to the ARU inner unit 3400 along the contact seam 3730.

[0293] The anti-resonant element has a wall thickness of 500 nm, which specifically corresponds to a wide transmission range (first transmission band) around the 1,550 nm signal wavelength. Two designs are used to simulate the anti-resonant hollow fiber 1000. The difference between the two designs is that...

[0294] In Design 1, the radius FA_R of the first circle is 15.75 μm, and

[0295] • In Design 2, the radius of the first circle FA_R is 12.25 μm.

[0296] The second circle radius FI_R corresponds to the first circle radius FA_R. All other parameters are the same in both designs. These and other parameters for the simulated anti-resonant hollow fiber 1000 can be found in Table 1.

[0297]

[0298]

[0299] Table 1: Parameters of Simulated Anti-Resonant Hollow-Core Fiber 1000

[0300] The following models were considered during the simulation:

[0301] ·The base model in the core

[0302] Also known as the core base mold;

[0303] ·High-order mode in the core

[0304] Also known as a high-order core mold (HOM),

[0305] • In the simulation, only the second-order mode (i.e., the first-order mode above the fundamental mode) is considered because the third-order and higher-order modes typically have even higher waveguide losses and are therefore less relevant when considering the fundamental mode, which is mainly determined by the power and waveguide loss in the second-order mode.

[0306] ·Modules in ARU external units

[0307] Also known as the anti-resonant unit mode or ARU mode, it propagates within the first internal space 3170 of the ARU outer unit.

[0308] • In the simulation, only the fundamental mode in the external elements of the ARU is considered;

[0309] ·Module in ARU arc unit

[0310] Also known as the arc-shaped element mode or DNE mode, it propagates within the third internal space 3970 of the ARU arc-shaped element.

[0311] • In the simulation, only the fundamental mode in the ARU arc element is considered.

[0312] The following is a more detailed explanation. Figures 8 to 11 The parameters used.

[0313] Effective modulus index n eff via relation v 相 =c / n eff This indicates the phase velocity of each mode in the direction of propagation along the fiber axis, where c represents the speed of light in a vacuum.

[0314] Effective modulus exponential difference Δn eff (ARU) represents the difference between the effective mode index of the higher-order mode in the core and the effective mode index of the anti-resonant mode (ARU mode):

[0315] Δn eff (ARU) = n eff ,Core-HOM-n eff,ARU模 .

[0316] Δn eff (DNE) is equivalent to the difference between the effective modulus index of the higher-order modes in the core and the effective modulus index of the arc element mode (DNE mode):

[0317] Δn eff (DNE)=n eff ,Core-HOM-n eff,DNE模 .

[0318] If the difference Δn in the two described cases eff Approaching zero, each of these modes propagates at approximately the same phase propagation speed and can therefore be coherently (in phase) coupled, resulting in effective energy coupling. In this case, energy from higher-order core modes is coupled into high-loss ARU or DNE modes. Thus, energy transfer from higher-order core modes improves the fundamental mode.

[0319] In the simulation, the effective mode exponent n is extracted from the propagation constant β of the corresponding mode. eff Modulus "j" is a solution to the system of physical equations:

[0320] E j (x,y,z,t)=amplitude j (x,y)*exp(i*(β j *z-ω*t)).

[0321] Here,

[0322] ·E j (x,y,z,t) describes the electric field distribution in the three spatial dimensions x,y,z at time t.

[0323] ·amplitude j (x,y) describes the transverse electric field distribution.

[0324] Therefore, the propagation constant β describes the phase characteristics of wave propagation along the fiber axis z. Based on the wavelength λ of the light, the n-mode "j" eff Obtained directly from β:

[0325] β j =2*pi / λ*n eff,j .

[0326] As a solution to the simulation, the propagation constant β of the j-th mode j Typically, these are complex parameters. When the real part produces n_eff,j, the waveguide loss for a given core mode can be derived from the imaginary part. Therefore, the parameter β... j It includes all the features that are important here.

[0327] In particular, it overcomes the aforementioned drawbacks of known ARHCFs when achieving fast fundamental mode. This is intended to mean that higher-order modes attenuate in the core, and that after a short travel distance, the anti-resonant hollow fiber effectively behaves as the fundamental mode. The shorter the travel distance, the higher the fundamental mode. The physical background is that the energy of higher-order modes in the core is coupled into the more lossy ARU and / or DNE modes. This means that higher-order modes no longer make a destructive contribution to optical signal transmission in the core.

[0328] Simulations of the anti-resonant hollow fiber 1000 surprisingly demonstrate the influence of the geometry of the ARU arc cell 3900 on the fundamental mode. In particular, the ratio of twice the radius of the ARU arc cell FB_R 3920 to the fiber core radius R_Faser 2310 has proven to be crucial.

[0329] exist Figure 8 In the figure, the effective mode exponent difference Δneff(DNE) is plotted as a ratio of twice the radius of the ARU arc cell FB_R 3920 to the fiber core radius R_Faser 2310.

[0330] • The results indicated by points are based on Design 1 for Δn eff (DNE) is used for drawing.

[0331] and

[0332] The results indicated by asterisks are based on Design 2 for Δn eff (DNE) is used for drawing.

[0333] Use curve fitting to fit the curves to these two sets of results.

[0334] Δn with a small value eff (DNE) is desired, indicating the efficient energy coupling between associated modes through adapted phase propagation speeds. The difference between Design 1 and Design 2 will not result in a change every time for Δn. eff The results of the (DNE) calculation show a strong variation. Conversely, the two curves fit each other very closely, or even overlap. A small Δn is achieved if the following ratio of twice the radius FB_R 3920 of the ARU arc cell to the fiber core radius R_Faser 2310 is used, especially for the first circle radius FA_R between 12.25 μm and 15.75 μm. eff (DNE):

[0335]

[0336] Furthermore, this implementation variation allows for greater flexibility in optimally adjusting the coupling between the ARU and / or DNE molds and higher-order core molds by specifying a reasonable geometric space.

[0337] If the ratio of twice the radius of the ARU arc unit FB_R 3920 to the fiber core radius R_Faser 2310 is applied, the following can be used to further positively influence the difference in phase propagation speed:

[0338] • 2*FB_R / R_Faser is greater than or equal to 0.8, especially greater than or equal to 0.9, especially greater than or equal to 1.0; and

[0339] • 2*FB_R / R_Faser is less than or equal to 1.6, especially less than or equal to 1.5, especially less than or equal to 1.45.

[0340] During the simulation of the anti-resonant hollow fiber 1000, it was surprisingly shown that the relationship between the geometry of the ARU arc unit 3900 and the geometry of the ARU outer unit affects the fundamental mode. In particular, the ratio of the fiber spatial height FH_Z1 3800 to the fiber core radius R_Faser 2310 is significant. Figure 9 and Figure 10 This demonstrates the positive characteristics of the ratio.

[0341] exist Figure 9 In the figure, the effective mode index Δneff (ARU) of the two designs is plotted relative to the ratio of the fiber spatial height FH_Z1 3800 to the fiber core radius R_Faser 2310, where

[0342] • The results indicated by points are based on Design 1 for Δn eff (ARU) is used for drawing.

[0343] and

[0344] The results indicated by asterisks are based on Design 2 for Δn eff (ARU) is used for drawing.

[0345] Use curve fitting to fit the curves to these two sets of results.

[0346] like Figure 9 As shown, in Design 1, the fundamental mode is achieved at a smaller ratio of fiber spatial height to fiber core radius compared to Design 2. In this regard, if the following applies to the ratio of fiber spatial height FH_Z1 3800 to fiber core radius R_Faser2310, then a fast fundamental mode is achieved in Design 1:

[0347]

[0348] like Figure 9 As shown, in Design 2, the fundamental mode is achieved at a larger ratio of fiber spatial height to fiber core radius compared to Design 1. In this regard, if the following applies to the ratio of fiber spatial height FH_Z1 3800 to fiber core radius R_Faser2310, then a fast fundamental mode is achieved in Design 2:

[0349]

[0350] In conjunction with this, in one implementation variation, the first circle radius FA_R between 12.25 μm and 15.75 μm specifically spans the space used for the ratio of fiber spatial height FH_Z1 3800 to fiber core radius R_Faser 2310:

[0351]

[0352] If the following applies to the ratio of fiber spatial height FH_Z1 to fiber core radius R_Faser, especially for the first circle radius FA_R between 12.25 μm and 15.75 μm, a further positive effect on the coupling of phase propagation speed can be achieved:

[0353] • FH_Z1 / R_Faser is greater than or equal to 0.8, especially greater than or equal to 0.85, especially greater than or equal to 0.9, especially greater than or equal to 0.95, especially greater than or equal to 1.0, and

[0354] • FH_Z1 / R_Faser is less than or equal to 1.4, especially less than or equal to 1.35, especially less than or equal to 1.3, especially less than or equal to 1.2.

[0355] exist Figure 10 In this paper, the waveguide loss difference (also known as loss discrimination, LM, or waveguide loss differential) between the fundamental and higher-order modes in the core of two hollow fiber designs is plotted as a ratio of the fiber spatial height FH_Z1 to the fiber core radius R_Faser. The waveguide loss difference is defined as follows:

[0356] LM(FM vs HOM) = 10 * log 10 (HOM attenuation / FM attenuation).

[0357] In this respect, the term attenuation specifically refers to the calculated waveguide loss for each mode, where

[0358] • The results, indicated by points, are plotted based on Design 1 to account for waveguide loss differences, and

[0359] The results, indicated by asterisks, are plotted based on the waveguide loss difference in Design 2.

[0360] Curve fitting is used to fit the curve to these two sets of results, and the curve has the shape of a resonance curve. The high loss discriminant value indicates a high difference in waveguide loss between the fundamental mode and higher-order modes, and is therefore desirable for the fundamental mode achieved over short travel distances.

[0361] like Figure 10 As illustrated, the hollow-core fiber with Design 1 achieves the maximum waveguide loss difference when the following applies to the ratio of fiber spatial height FH_Z1 to fiber core radius R_Faser:

[0362]

[0363] like Figure 10 As further illustrated, the hollow-core fiber with Design 2 achieves the maximum waveguide loss difference when the following applies to the ratio of fiber spatial height FH_Z1 to fiber core radius R_Faser:

[0364]

[0365] In conjunction with this, in a variant of the implementation, if the following applies to the ratio of fiber spatial height FH_Z1 to fiber core radius R_Faser, then hollow-core fibers with a first circular radius FA_R between 12.25 μm and 15.75 μm achieve the maximum waveguide loss difference:

[0366]

[0367] Simulations of anti-resonant hollow fiber also surprisingly show that the geometry of the anti-resonant unit (especially the ARU arc unit) affects the attenuation of the ARHCF, which in Figure 11 Example in.

[0368] exist Figure 11 In the diagram, for both designs, the confinement loss of the fundamental mode at 1,550 nm wavelength (also known as waveguide loss) is plotted as a ratio of twice the fiber spatial height FH_Z1 3800 to the radius FB_R 3920 of the ARU arc cell.

[0369] • The results, indicated by points, are plotted based on Design 1 for waveguide loss, and

[0370] The results, indicated by asterisks, are plotted based on Design 2 for waveguide loss.

[0371] Use curve fitting to fit the curves to these two sets of results.

[0372] like Figure 11 As shown, if in Design 1, the following ratio is applied: fiber spatial height FH_Z13800 to twice the radius FB_R 3920 of the ARU arc unit, then low attenuation is achieved, which overcomes at least some of the aforementioned disadvantages:

[0373]

[0374] If the following ratio applies to twice the fiber spatial height FH_Z1 3800 and the radius FB_R 3920 of the ARU arc cell, then a further positive impact on attenuation can be achieved in Design 1:

[0375]

[0376] like Figure 11 As shown, if in Design 2, the following ratio is applied: fiber spatial height FH_Z13800 to twice the radius FB_R 3920 of the ARU arc unit, then low attenuation is achieved, overcoming at least some of the aforementioned disadvantages:

[0377]

[0378] If the following ratio applies to twice the fiber spatial height FH_Z1 3800 and the radius FB_R 3920 of the ARU arc cell, then a further positive impact on attenuation can be achieved in Design 2:

[0379]

[0380] exist Figure 11In the illustrated implementation variation, if the following applies to a ratio of twice the fiber optic chamber height FH_Z1 3800 to the radius FB_R 3920 of the ARU arc unit, then the first circular radius FA_R between 12.25 μm and 15.75 μm spans the space used for the design of the ARHCF with low attenuation:

[0381]

[0382] The reason for the ARU arc-shaped unit described in this implementation variant is as follows:

[0383] • The fundamental mode in the core is almost not coupled with the DNE mode, but at the same time

[0384] • The higher-order modes in the core are effectively coupled with the arc-shaped unit modes with greater losses.

[0385] This results in an ARHCF that, on the one hand, enters the fundamental mode over a short distance, and on the other hand, has only the low attenuation of the fundamental mode.

[0386] Another variant of the implementation is characterized by the following application for a ratio of twice the fiber spatial height FH_Z1 3800 to the radius FB_R 3920 of the ARU arc cell:

[0387] • FH_Z1 / (2*FB_R) is less than or equal to 1.2, especially less than or equal to 1.05, especially less than or equal to 1.0, especially less than or equal to 0.9, especially less than or equal to 0.85, especially less than or equal to 0.8; and

[0388] ·FH_Z1 / (2*FB_R) is greater than or equal to 0.1, especially greater than or equal to 0.125, especially greater than or equal to 0.15, especially greater than or equal to 0.2, especially greater than or equal to 0.4, especially greater than or equal to 0.5.

[0389] The feature of this implementation variation is its positive impact on attenuation.

[0390] The antiresonant hollow fiber 1000 is characterized in that the deviation between the first circular radius FA_R 3200 and the second circular radius FI_R 3500 is less than 10% of the first circular radius FA_R 3200. To determine the impact of these differences in the two circular radii on the fundamental mode, simulations were performed on two additional designs of the antiresonant hollow fiber 1000. Table 2 shows the different parameters for simulating the antiresonant hollow fiber 1000.

[0391]

[0392]

[0393] Table 2: Parameters of Simulated Anti-Resonant Hollow-Core Fiber 1000

[0394] All other parameters correspond to those listed in Table 1 and / or those described in more detail above for the anti-resonant hollow fiber 1000 according to Design 1. Therefore, two simulations are performed where only the second circle radius FI_R is changed by + / - 10% relative to the first circle radius FA_R.

[0395] exist Figure 12 The results of the simulation are listed below. The effective mode exponent difference Δneff(DNE) is plotted as a ratio of twice the radius of the ARU arc cell FB_R 3920 to the fiber core radius R_Faser 2310.

[0396] The results indicated by the point are based on Design 1 for Δn eff (DNE) is used for drawing.

[0397] These results and Figure 8 The results are the same.

[0398] The results indicated by the circles are based on Design 3 for Δn. eff (DNE) is used for drawing, and

[0399] The results indicated by the rectangle are based on Design 4 for Δn eff (DNE) is used for drawing.

[0400] Use curve fitting to fit the curve to the set of results for Design 1.

[0401] The calculated values ​​for Designs 3 and 4 lie directly on the curve fitted to the values ​​of Design 1. In this respect, the first circle radius FA_R 3200 and the second circle radius FI_R 3500 span the space for designs with low attenuation within a variation of less than or equal to 10% of the first circle radius FA_R 3200.

[0402] Figure Labels

[0403] 1000 anti-resonant hollow fiber

[0404] 2000 cladding or fiber optic cladding

[0405] 2150 inner side of the cladding

[0406] 2250 inner radius of cladding

[0407] 2300 Fiber longitudinal axis

[0408] 2310 Core radius R_Faser

[0409] 2470 hollow core

[0410] 2980 First Circle

[0411] 2990 Second Circle

[0412] 3000 Anti-resonant Units (ARU)

[0413] ARU external unit of 3100 anti-resonant hollow fiber

[0414] 3110 First main longitudinal axis

[0415] 3150 ARU outer unit wall

[0416] The first internal space of the 3170 ARU external unit

[0417] 3200 First circle radius FA_R

[0418] 3250 First central angle FA_MW

[0419] 3280 First Section Height

[0420] 3290 First chord length

[0421] ARU inner unit of 3400 anti-resonant hollow fiber

[0422] 3410 Second main longitudinal axis

[0423] 3450 ARU inner unit wall

[0424] The second internal space of the 3470 ARU inner unit

[0425] 3500 Second circle radius FI_R

[0426] 3550 Second central angle FI_MW

[0427] 3580 Second section height F_Innen

[0428] 3590 Second chord length

[0429] 3700, 3700' connection seam

[0430] 3730 Contact joint

[0431] 3800 fiber optic spatial height (FH_Z1)

[0432] 3900 ARU arc-shaped unit

[0433] 3910 First main longitudinal axis

[0434] The radius FB_R of the 3920 ARU arc element

[0435] 3950 Curved Wall

[0436] The third interior space of the 3970 ARU arc-shaped unit

[0437] The diameter FB_D of the 3980 ARU arc element

Claims

1. An anti-resonant hollow-core optical fiber (1000), comprising: The longitudinal axis of the optical fiber is (2300) and the core radius of the optical fiber is R_Faser (2310). The optical fiber cladding (2000) includes an inner cladding aperture (2200) and multiple anti-resonant elements (3000). Each anti-resonant unit includes an ARU outer unit (3100) and an ARU inner unit (3400). • The arc-shaped ARU outer unit (3100) and the arc-shaped ARU inner unit (3400) are connected to each other along two seam lines (3700, 3700'), such that the ARU inner unit (3400) at least partially protrudes into the first internal space (3170) of the ARU outer unit (3100). The anti-resonant units (3000) are spaced apart from each other and arranged so as not to contact each other at desired positions on the inner side (2150) of the cladding. in The ARU outer unit (3100) has a first circular radius FA_R (3200) and a first central angle FA_MW (3250). The ARU inner unit (3400) has a second circular radius FI_R (3500) and a second central angle FI_MW (3550). The deviation between the first circle radius FA_R (3200) and the second circle radius FI_R (3500) is less than 10% of the first circle radius FA_R (3200). • The first central angle FA_MW(3250) is less than 345° and greater than 275°, and The second central angle FI_MW (3550) is less than 195° and greater than 40°, wherein in at least one anti-resonant unit (3000) • The ARU arc-shaped unit (3900) is arranged in the first internal space (3170). The ARU arc-shaped unit (3900) is circular. It has a radius FB_R(3920), and The ARU arc-shaped unit (3900) is connected to the ARU inner unit (3400) along the contact seam (3730). Its features are, The following applies to the ratio of twice the radius FB_R (3920) of the ARU arc unit to the fiber core radius R_Faser (2310).

2. The anti-resonant hollow-core optical fiber (1000) according to claim 1, characterized in that, The following applies to the ratio of twice the radius FB_R (3920) of the ARU arc unit to the fiber core radius R_Faser (2310): • 2*FB_R / R_Faser is greater than or equal to 0.8, especially greater than or equal to 0.9, especially greater than or equal to 1.0; and • 2*FB_R / R_Faser is less than or equal to 1.6, especially less than or equal to 1.5, especially less than or equal to 1.

45.

3. The anti-resonant hollow optical fiber (1000) according to claim 1 or 2, characterized in that, The anti-resonant unit (3000) has an optical fiber spatial height FH_Z1 (3800), and the following applies to the ratio of the optical fiber spatial height FH_Z1 (3800) to the optical fiber core radius R_Faser (2310):

4. The anti-resonant hollow-core optical fiber (1000) according to claim 3, characterized in that, The following applies to the ratio of the fiber spatial height FH_Z1 (3800) to the fiber core radius R_Faser (2310): • FH_Z1 / R_Faser is greater than or equal to 0.8, especially greater than or equal to 0.85, especially greater than or equal to 0.9, especially greater than or equal to 0.95, especially greater than or equal to 1.0, and • FH_Z1 / R_Faser is less than or equal to 1.4, especially less than or equal to 1.35, especially less than or equal to 1.3, especially less than or equal to 1.

2.

5. The anti-resonant hollow-core optical fiber (1000) according to any one of the preceding claims, characterized in that, The following applies to the ratio of the optical fiber spatial height FH_Z1 (3800) to twice the radius FB_R (3920) of the ARU arc unit: Especially ≤1.

3.

6. The anti-resonant hollow-core optical fiber (1000) according to claim 5, characterized in that, The following applies to the ratio of the optical fiber spatial height FH_Z1 (3800) to twice the radius FB_R (3920) of the ARU arc unit: • FH_Z1 / (2*FB_R) is less than or equal to 1.2, especially less than or equal to 1.05, especially less than or equal to 1.0, especially less than or equal to 0.9, especially less than or equal to 0.85, especially less than or equal to 0.8; and ·FH_Z1 / (2*FB_R) is greater than or equal to 0.1, especially greater than or equal to 0.125, especially greater than or equal to 0.15, especially greater than or equal to 0.2, especially greater than or equal to 0.4, especially greater than or equal to 0.

5.

7. The anti-resonant hollow-core optical fiber (1000) according to any one of the preceding claims, characterized in that, The deviation between the first circle radius FA_R and the second circle radius FI_R is less than 5% of the first circle radius FA_R, especially less than 3%, especially less than 2%, especially less than 1%.

8. The anti-resonant hollow-core optical fiber (1000) according to any one of the preceding claims, characterized in that, The anti-resonant hollow fiber (1000) includes three, four, five, six, seven or eight anti-resonant units (3000).

9. The anti-resonant hollow-core optical fiber (1000) according to any one of the preceding claims, characterized in that, At least one of the anti-resonant units (3000) has at least one of the following characteristics: The ARU outer unit (3100) and / or the ARU inner unit (3400) and / or the ARU arcuate unit (3900) comprise an amorphous solid body, particularly glass, especially quartz glass. The ARU outer unit (3100) and / or the ARU inner unit (3400) and / or the ARU arcuate unit (3900) are composed of an amorphous solid body, particularly glass, especially quartz glass. The ARU outer unit (3100) and / or the ARU inner unit (3400) and / or the ARU arcuate unit (3900) are made of the same material, particularly comprising or composed of glass having a refractive index of at least 1.4, particularly 1.4 to 3, particularly 1.4 to 2.8, and The wall thicknesses of the ARU outer unit (3100), the ARU inner unit (3400), and the ARU arc-shaped unit (3900) are substantially the same.

10. The anti-resonant hollow-core optical fiber (1000) according to any one of the preceding claims, characterized in that, The anti-resonant hollow fiber (1000) has at least one of the following characteristics: For transmission wavelengths between 1.0 μm and 2.5 μm, the basic attenuation is less than 1.0 dB / km, particularly less than 0.5 dB / km, particularly less than 0.25 dB / km, and particularly less than 0.15 dB / km. • For transmission wavelengths up to 0.8 μm, the basic attenuation is less than 1 dB / km.

11. The anti-resonant hollow-core optical fiber (1000) according to any one of the preceding claims, characterized in that, For the first circle radius F_R (3200) and / or the second circle radius FI_R (3500), the following applies: The radius of the first circle and / or the radius of the second circle is less than 30 μm, particularly less than 20 μm, particularly less than 17.5 μm, particularly less than or equal to 16.5 μm, particularly less than or equal to 15.75 μm, and / or • The radius of the first circle and / or the radius of the second circle is greater than 5 μm, particularly greater than 10 μm, particularly greater than or equal to 11.5 μm, particularly greater than or equal to 12.25 μm.

12. The anti-resonant hollow-core optical fiber (1000) according to any one of the preceding claims, characterized in that, At least one ARU arc-shaped unit (3900) has at least one of the following characteristics: The radius FB_R(3920) of the ARU arc-shaped unit is less than 15 μm, particularly less than 12.5 μm, particularly less than 11 μm, and particularly less than 9.5 μm. The radius FB_R(3920) of the ARU arc-shaped unit is greater than 0.75 μm, particularly greater than 1 μm, and particularly greater than 2.5 μm.

13. The anti-resonant hollow-core optical fiber (1000) according to any one of the preceding claims, characterized in that, At least one of the anti-resonant units (3000) has at least one of the following characteristics: The wall thickness of the ARU outer unit and / or the ARU inner unit and / or the ARU arc-shaped unit is between 0.1 μm and 2.5 μm, particularly between 0.15 μm and 1.5 μm, particularly between 0.25 μm and 0.75 μm, particularly between 0.35 μm and 0.65 μm, and particularly 0.5 μm. For a signal wavelength of 1550 nm in the first transmission window, the wall thickness of the ARU outer unit and / or the ARU inner unit and / or the ARU arc-shaped unit is between 0.35 μm and 0.65 μm, particularly between 0.4 μm and 0.6 μm, and especially 0.5 μm. • For a signal wavelength of 1550 nm in the second transmission window, the wall thickness of the ARU outer unit and / or the ARU inner unit and / or the ARU arc unit is between 0.75 μm and 1.25 μm, particularly between 0.9 μm and 1.1 μm, and especially 1 μm.

Images