Photonic crystal fiber, optical communication device

Abstract

The application provides a photonic crystal fiber and an optical communication device. The photonic crystal fiber comprises a core and a cladding, the cladding is arranged around the core; the core is a high refractive index region formed by two first holes and a plurality of second holes; in the core, the two first holes are oppositely arranged, the plurality of second holes comprises a plurality of first sub-holes and a plurality of second sub-holes, the plurality of first sub-holes are arranged on one side of the first hole, the plurality of second sub-holes are arranged on the other side of the first hole, the distance between the centers of the two opposite first holes is a first distance H1, 4.5 μm≤H1≤6.5 μm; the cladding has a low refractive index region formed by the arrangement of the plurality of second holes. The application forms a defect on the photonic crystal fiber by arranging the high refractive region formed by the first holes and the second holes with different hole diameters and limiting the distance between the centers of the two first holes, thereby forming an asymmetric structure, obtaining a photonic crystal fiber with high birefringence, and further improving the optical transmission performance of the photonic crystal fiber.

Description

Technical Field

[0001] This application belongs to the field of optical fiber technology, specifically relating to photonic crystal optical fibers and optical communication equipment. Background Technology

[0002] Photonic crystal fibers have wide applications in optical communication, such as fiber optic communication, fiber optic sensing, optical sensing, and wavelength converters. However, the birefringence of photonic crystal fibers in related technologies is approximately 10. -4 The level of optical fiber limits its optical transmission performance. Utility Model Content

[0003] In view of this, the first aspect of this application provides a photonic crystal fiber, the photonic crystal fiber including a core and a cladding, the cladding being disposed around the core, the photonic crystal fiber having a first hole and a second hole, the aperture of the first hole being larger than the aperture of the second hole; The fiber core is a high refractive index region formed by two first holes and a plurality of second holes; in the fiber core, the two first holes are arranged opposite each other, and the plurality of second holes include a plurality of first sub-holes and a plurality of second sub-holes. The plurality of first sub-holes are located on one side of the first holes, and the plurality of second sub-holes are located on the other side of the first holes. The distance between the centers of two opposite first holes is a first distance H1, which satisfies the following condition: 4.5μm≤H1≤6.5μm; the cladding has a low refractive index region formed by the arrangement of a plurality of second holes.

[0004] The distance between the centers of the first sub-hole and the second sub-hole is the second distance H2, which satisfies the following condition: 4μm≤H2≤6μm.

[0005] Wherein, the first spacing H1 is equal to the second spacing H2.

[0006] The ratio of the diameter d1 of the first hole to the diameter d2 of the second hole satisfies the following condition: d1 / d2 = 1.5~1.85.

[0007] The photonic crystal fiber satisfies at least one of the following conditions: The aperture d1 of the first hole satisfies the following condition: 3μm≤d1≤4μm; The aperture d2 of the second hole satisfies the following condition: 1.5μm≤d2≤2.5μm.

[0008] In the cladding layer, the plurality of second holes are arranged in an array, forming multiple rows. The second holes in the Mth row are directly corresponding to the second holes in the M+2th row, and the second holes in the Mth row are alternately arranged with the second holes in the M+1th row, where M is a positive integer.

[0009] In the cladding layer, the plurality of second holes form multiple columns, with the second hole in the Nth column corresponding to the second hole in the (N+2)th column, and the second hole in the Nth column being staggered with the second hole in the (N+1)th column, where N is a positive integer.

[0010] In the cladding, the distance between adjacent centers of the second hole is a third distance H3, which satisfies the following condition: 1.96μm<H3≤4μm.

[0011] For light rays with wavelengths of 1.3 μm to 3.2 μm, the birefringence B of the photonic crystal fiber satisfies the following condition: 5 × 10⁻⁶. -3 ≤B≤18.5×10 -3 .

[0012] The second aspect of this application provides an optical communication device, which includes an optical emitting chip, an optical receiving chip, and a photonic crystal fiber as provided in the first aspect of this application. The photonic crystal fiber is used to receive emitted light emitted by the optical emitting chip and is also used to emit incident light so that the incident light is directed to the optical receiving chip.

[0013] The photonic crystal fiber and optical communication equipment provided in this application form a high-refractive-index photonic crystal fiber by setting a high-refractive-index region enclosed by a first aperture and a second aperture of different apertures and limiting the distance between the centers of the two first apertures, thereby creating a defect on the photonic crystal fiber to generate an asymmetric structure, thus obtaining a photonic crystal fiber with high birefringence and improving the optical transmission performance of the photonic crystal fiber. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0015] Figure 1 This is a schematic diagram of the structure of a photonic crystal fiber provided in one embodiment of this application.

[0016] Figure 2 This is a schematic diagram of the fiber core provided in one embodiment of this application.

[0017] Figure 3 This is a schematic diagram of the cladding structure provided in one embodiment of this application.

[0018] Figure 4 An energy simulation diagram of a photonic crystal fiber provided in one embodiment of this application.

[0019] Figure 5 A graph showing the birefringence B of a photonic crystal fiber provided in one embodiment of this application.

[0020] Labeling explanation: Photonic crystal fiber 1, first hole 11, second hole 12, first sub-hole 121, second sub-hole 122, core 10, cladding 20. Detailed Implementation

[0021] The following are preferred embodiments of this application. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

[0022] In view of this, in order to solve the above problems, please refer to the following: Figures 1-4 This embodiment provides a photonic crystal fiber 1, which includes a core 10 and a cladding 20. The cladding 20 is disposed around the core 10. The photonic crystal fiber 1 has a first hole 11 and a second hole 12, wherein the aperture of the first hole 11 is larger than the aperture of the second hole 12.

[0023] The fiber core 10 is a high refractive index region formed by two first holes 11 and a plurality of second holes 12. In the fiber core 10, the two first holes 11 are arranged opposite each other, and the plurality of second holes 12 include a plurality of first sub-holes 121 and a plurality of second sub-holes 122. The plurality of first sub-holes 121 are located on one side of the first holes 11, and the plurality of second sub-holes 122 are located on the other side of the first holes 11. The distance between the centers of two opposite first holes 11 is a first distance H1, which satisfies the following condition: 4.5μm≤H1≤6.5μm. The cladding 20 has a low refractive index region formed by the arrangement of a plurality of second holes 12.

[0024] The photonic crystal fiber 1 has a first aperture 11 and a second aperture 12. The shapes of the first aperture 11 and the second aperture 12 can be circular, near-circular, elliptical, or near-elliptical, etc., and this embodiment is not limited to these shapes. The fiber core 10 is located at the center of the photonic crystal fiber 1, and the cladding 20 surrounds the fiber core 10, extending circumferentially along the photonic crystal fiber 1. The energy distribution of the light is as follows... Figure 4 As shown, the fiber core 10 is a high-energy region where light is concentrated, and the cladding 20 is a low-energy region where light is sparse, with the energy of the low-energy region approaching zero. Optionally, the first hole 11 and the second hole 12 are filled with a substance, which can be a gas, liquid, or solid. For example, air is filled into the first hole 11 and the second hole 12.

[0025] Specifically, the diameter of the first hole 11 is larger than the diameter of the second hole 12. In one embodiment, the ratio of the diameter d1 of the first hole 11 to the diameter d2 of the second hole 12 satisfies the following condition: d1 / d2 = 1.5~1.85, where d1 / d2 can be 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, or 1.85, etc. More specifically, the diameter d1 of the first hole 11 satisfies the following condition: 3μm ≤ d1 ≤ 4μm, where d1 can be 3μm, 3.1μm, 3.2μm, 3.3μm, 3.4μm, 3.5μm, 3.6μm, 3.7μm, 3.8μm, 3.9μm, or 4μm, etc. The aperture d2 of the second hole 12 satisfies the following condition: 1.5μm≤d2≤2.5μm. Specific examples of d2 include 1.5μm, 1.6μm, 1.7μm, 1.8μm, 1.9μm, 2μm, 2.1μm, 2.2μm, 2.3μm, 2.4μm, and 2.5μm, etc.

[0026] In the fiber core 10, the first hole 11 is located at the center of the photonic crystal fiber 1, and two first holes 11 are located between the second holes 12. The second holes 12 are staggered with the first holes 11, that is, the second holes 12 are located between the gaps between the two first holes 11.

[0027] In the fiber core 10, the plurality of second holes 12 include a plurality of first sub-holes 121 and a plurality of second sub-holes 122. The positions of the first sub-holes 121 and second sub-holes 122 are different, and the first sub-holes 121 and second sub-holes 122 are located on opposite sides of the first hole 11. For example, the first hole 11 is located in the center, and the first sub-holes 121 and second sub-holes 122 are located on the upper and lower sides of the first hole 11, respectively. The number of first sub-holes 121 and second sub-holes 122 is equal, and the number of each is 2 to 6. The first sub-holes 121 are positioned between two first holes 11, and the second sub-holes 122 are positioned between two first holes 11. The diameters of the first sub-holes 121 and second sub-holes 122 are equal. The first sub-holes 121 and second sub-holes 122 are positioned directly opposite each other.

[0028] For example, the fiber core 10 is a high refractive index region formed by two first holes 11 and four second holes 12; in the fiber core 10, the two first holes 11 are arranged opposite each other, the two second holes 12 are located on one side of the first holes 11, and the other two second holes 12 are located on the other side of the first holes 11. The two first holes 11 and the four second holes 12 form a hexagon.

[0029] In the fiber core 10, the arrangement direction of the two first holes 11 is a preset direction, the arrangement direction of the first sub-holes 121 is the same as the preset direction, and the arrangement direction of the second sub-holes 122 is the same as the preset direction.

[0030] For example, the two first holes 11 are arranged in a horizontal direction, the first sub-hole 121 is located above the first hole 11 and is arranged in a horizontal direction, and the second sub-hole 122 is located below the first hole 11 and is arranged in a horizontal direction.

[0031] For example, the two first holes 11 are arranged in a vertical direction, the first sub-hole 121 is located to the left of the first hole 11 and is arranged in a vertical direction, and the second sub-hole 122 is located to the right of the first hole 11 and is arranged in a horizontal direction.

[0032] The distance between the centers of two opposite first holes 11 is the first distance H1, which satisfies the following condition: 4.5μm≤H1≤6.5μm. H1 can be exemplified as 4.5μm, 4.7μm, 4.8μm, 5μm, 5.2μm, 5.3μm, 5.5μm, 5.7μm, 5.8μm, 6μm, 6.2μm, or 6.5μm, etc. The distance between the centers of the first sub-hole 121 and the second sub-hole 122 is a second distance H2, which satisfies the following condition: 4μm ≤ H2 ≤ 6μm. Specifically, H2 can be 4μm, 4.2μm, 4.4μm, 4.6μm, 4.8μm, 5μm, 5.2μm, 5.4μm, 5.6μm, 5.8μm, or 6μm, etc. In one embodiment, the first distance H1 is equal to the second distance H2.

[0033] In one embodiment, in the cladding 20, the plurality of second holes 12 are arranged in an array, forming multiple rows, with the second holes 12 in the Mth row corresponding to the second holes 12 in the M+2th row, and the second holes 12 in the Mth row being alternately arranged with the second holes 12 in the M+1th row, where M is a positive integer.

[0034] Specifically, the gap between the second holes 12 in the Mth row and the second holes 12 in the (M+1)th row is set, the gap between the second holes 12 in the (M+1)th row and the second holes 12 in the (M+2)th row is set, and the second holes 12 in the Mth row correspond exactly to the second holes 12 in the (M+2)th row. In other words, the second holes 12 in adjacent rows are staggered.

[0035] In one embodiment, in the cladding 20, the plurality of second holes 12 form multiple columns, the second holes 12 in the Nth column are directly corresponding to the second holes 12 in the (N+2)th column, and the second holes 12 in the Nth column are alternately arranged with the second holes 12 in the (N+1)th column, where N is a positive integer.

[0036] Specifically, the gap between the second holes 12 in the Nth column corresponds to the gap between the second holes 12 in the (N+1)th column, and the gap between the second holes 12 in the (N+1)th column corresponds to the gap between the second holes 12 in the (N+2)th column. In other words, the second holes 12 in adjacent columns are staggered.

[0037] In the cladding 20, the plurality of second holes 12 are arranged to form a hexagon, and the number of rows I and the number of columns J satisfy the following conditions: 15≤I≤20, 13≤J≤17, where I and J are positive integers.

[0038] The outer periphery of multiple second holes 12 is surrounded to form a hexagon. The number of rows I can be 15, 16, 17, 18, 19, or 20; the number of columns J can be 13, 14, 15, 16, or 17. Optionally, the number of rows I is equal to the number of columns J.

[0039] In one embodiment, in the cladding 20, the distance between the centers of adjacent second holes 12 is a third distance H3, which satisfies the following condition: 1.96μm < H3 ≤ 4μm. H3 can be specifically exemplified as 1.99μm, 2μm, 2.2μm, 2.4μm, 2.6μm, 2.8μm, 3μm, 3.2μm, 3.4μm, 3.6μm, 3.8μm, or 4μm, etc.

[0040] In one embodiment, the first distance H1 between the centers of two opposing first holes 11 is equal to the third distance H3 between the centers of adjacent second holes 12. The second distance H2 between the centers of opposing first sub-holes 121 and second sub-holes 122 is equal to the third distance H3 between the centers of adjacent second holes 12.

[0041] Please refer to Figure 5 In one embodiment, for light with wavelengths of 1.3 μm to 3.2 μm, the birefringence B of the photonic crystal fiber 1 satisfies the following condition: 5 × 10⁻⁶. -3 ≤B≤18.5×10 -3 .

[0042] For example, the birefringence B of photonic crystal fiber 1 can be 5 × 10⁻⁶. -3 or 6×10 -3or 7×10 -3 or 8×10 -3 or 9×10 -3 or 10×10 -3 or 11×10 -3 or 12×10 -3 or 13×10 -3 or 14×10 -3 or 15×10 -3 or 16×10 -3 or 17×10 -3 or 18×10 -3 or 18.5×10 -3 wait.

[0043] In summary, the photonic crystal fiber 1 provided in this application forms a high refractive index photonic crystal fiber 1 by setting a high refractive index region surrounded by a first aperture 11 and a second aperture 12 with different aperture sizes, and limiting the distance between the centers of the two first apertures 11, thereby forming a defect on the photonic crystal fiber 1 to generate an asymmetric structure, thereby obtaining a photonic crystal fiber 1 with high birefringence, and thus improving the optical transmission performance of the photonic crystal fiber 1.

[0044] This application also provides an optical communication device, which includes an optical emitting chip, an optical receiving chip, and a photonic crystal fiber as provided above. The photonic crystal fiber is used to receive emitted light emitted by the optical emitting chip and is also used to emit incident light so that the incident light hits the optical receiving chip.

[0045] The optical communication device provided in this application utilizes the photonic crystal fiber provided above. The photonic crystal fiber is configured with a high refractive index region formed by a first aperture and a second aperture with different apertures, and the distance between the centers of the two first apertures is limited. This results in the formation of a defect on the photonic crystal fiber to create an asymmetric structure, thereby obtaining a photonic crystal fiber with high birefringence and improving the optical transmission performance of the photonic crystal fiber.

[0046] Unless otherwise stated or in case of conflict, the terms or phrases used in this application shall have the following meanings: In this application, terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0047] In this application, "one or more" refers to any one, any two, or any two or more of the listed items. "Several" refers to any two or more.

[0048] In this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0049] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part. They can refer to a mechanical connection or an electrical connection. They can refer to a direct connection or an indirect connection through an intermediate medium, or the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0050] In this application, the terms "embodiment" and "implementation" mean that a specific feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of this application. The appearance of these phrases in various locations throughout the specification does not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Those skilled in the art will understand, explicitly and implicitly, that the embodiments described in this application can be combined with other embodiments. Furthermore, it should be understood that the features, structures, or characteristics described in the various embodiments of this application can be arbitrarily combined to form another embodiment that does not depart from the spirit and scope of the technical solution of this application, provided there is no contradiction between them.

[0051] The above description represents some embodiments of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

Claims

1. A photonic crystal fiber, characterized in that, The photonic crystal fiber includes a core and a cladding, the cladding being disposed around the core, and the photonic crystal fiber having a first aperture and a second aperture, the aperture of the first aperture being larger than the aperture of the second aperture; The fiber core is a high refractive index region formed by two first holes and a plurality of second holes; in the fiber core, the two first holes are arranged opposite each other, and the plurality of second holes include a plurality of first sub-holes and a plurality of second sub-holes. The plurality of first sub-holes are located on one side of the first holes, and the plurality of second sub-holes are located on the other side of the first holes. The distance between the centers of two opposite first holes is a first distance H1, which satisfies the following condition: 4.5μm≤H1≤6.5μm; the cladding has a low refractive index region formed by the arrangement of a plurality of second holes.

2. The photonic crystal fiber as described in claim 1, characterized in that, The relative distance between the center of the first sub-hole and the center of the second sub-hole is the second distance H2, which satisfies the following condition: 4μm≤H2≤6μm.

3. The photonic crystal fiber as described in claim 2, characterized in that, The first spacing H1 is equal to the second spacing H2.

4. The photonic crystal fiber as described in claim 1, characterized in that, The ratio of the diameter d1 of the first hole to the diameter d2 of the second hole satisfies the following condition: d1 / d2 = 1.5~1.

85.

5. The photonic crystal fiber as described in claim 4, characterized in that, The photonic crystal fiber satisfies at least one of the following conditions: The aperture d1 of the first hole satisfies the following condition: 3μm≤d1≤4μm; The aperture d2 of the second hole satisfies the following condition: 1.5μm≤d2≤2.5μm.

6. The photonic crystal fiber as described in claim 1, characterized in that, In the cladding, the plurality of second holes are arranged in an array, forming multiple rows. The second holes in the Mth row are directly corresponding to the second holes in the M+2th row, and the second holes in the Mth row are alternately arranged with the second holes in the M+1th row, where M is a positive integer.

7. The photonic crystal fiber as described in claim 6, characterized in that, In the cladding, the plurality of second holes form multiple columns, with the second hole in the Nth column corresponding to the second hole in the (N+2)th column, and the second hole in the Nth column being staggered with the second hole in the (N+1)th column, where N is a positive integer.

8. The photonic crystal fiber as described in claim 1, characterized in that, In the cladding, the distance between adjacent centers of the second hole is a third distance H3, which satisfies the following condition: 1.96μm < H3 ≤ 4μm.

9. The photonic crystal fiber as described in claim 1, characterized in that, For light rays with wavelengths of 1.3 μm–3.2 μm, the birefringence B of the photonic crystal fiber satisfies the following condition: 5 × 10⁻⁶. -3 ≤B≤18.5×10 -3 .

10. An optical communication device, characterized in that, The optical communication device includes an optical emitting chip, an optical receiving chip, and a photonic crystal fiber as described in any one of claims 1-9. The photonic crystal fiber is used to receive emitted light emitted by the optical emitting chip, and the photonic crystal fiber is also used to emit incident light so that the incident light is directed to the optical receiving chip.

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