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, and the photonic crystal fiber has first holes and second holes. In the core, three first holes comprise a first sub-hole and second sub-holes arranged on opposite sides of the first sub-hole, a first filler is arranged in the first sub-hole, a second filler is arranged in the second sub-hole, the refractive index of the first filler is smaller than the refractive index of the second filler, a plurality of second holes comprise a plurality of third sub-holes and a plurality of fourth sub-holes, the plurality of third sub-holes are arranged on one side of the first hole, and the plurality of fourth sub-holes are arranged on the other side of the first hole. The application forms a high-refraction area surrounded by the first holes and the second holes with different hole diameters, and the fillers are arranged in the first sub-hole and the second sub-hole, so that the asymmetric structure is formed on the photonic crystal fiber by the defect, the photonic crystal fiber with high birefringence is obtained, and the optical transmission performance of the photonic crystal fiber is improved.

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 smaller than the aperture of the second hole; The fiber core has a high refractive index region formed by three first holes and a plurality of second holes; in the fiber core, the three first holes include a first sub-hole and a second sub-hole disposed on opposite sides of the first sub-hole, the first sub-hole being filled with a first filler and the second sub-hole being filled with a second filler, the refractive index of the first filler being less than that of the second filler, the plurality of second holes include a plurality of third sub-holes and a plurality of fourth sub-holes, the plurality of third sub-holes being disposed on one side of the first hole and the plurality of fourth sub-holes being disposed on the other side of the first hole; the cladding has a low refractive index region formed by the arrangement of a plurality of first holes.

[0004] The refractive index of the first filler is 1-1.05, and the refractive index of the second filler is 1.4-1.5.

[0005] The first filler is an air filler, and the second filler is a refractive index adhesive filler.

[0006] In the fiber core, the three first holes are arranged in a preset direction, the plurality of third sub-holes are arranged in the same preset direction, and the plurality of fourth sub-holes are arranged in the same preset direction.

[0007] In the fiber core, there are four of each of the plurality of third sub-holes and the plurality of fourth sub-holes. The plurality of third sub-holes and the plurality of fourth sub-holes are arranged in direct correspondence. The three first holes are arranged alternately with the plurality of third sub-holes and the three first holes are arranged alternately with the plurality of fourth sub-holes.

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

[0009] In the cladding layer, the plurality of first holes form multiple columns, the first hole in the Nth column is directly corresponding to the first hole in the N+2th column, and the first hole in the Nth column is alternately arranged with the first hole in the N+1th column, where N is a positive integer.

[0010] The photonic crystal fiber satisfies at least one of the following conditions: The aperture d1 of the first hole satisfies the following condition: 0.5μm≤d1≤1.5μm; The aperture d2 of the second hole satisfies the following condition: 1μm≤d2≤2μm; In the cladding, the distance between adjacent centers of the first hole is a first distance H1, which satisfies the following condition: 1μm < H1 ≤ 2μm.

[0011] For light rays with wavelengths of 1.20 μm–2.35 μm, the birefringence B of the photonic crystal fiber satisfies the following condition: 5 × 10⁻⁶. -3 ≤B≤17.5×10 -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 surrounded by a first aperture and a second aperture with different aperture sizes, and filling the first and second sub-apertures with a filler material, wherein the refractive index of the first filler material is less than that of the second filler material, thereby forming a defect on the photonic crystal fiber to generate an asymmetric structure, thus obtaining a photonic crystal fiber with high birefringence, thereby 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, first sub-hole 111, second sub-hole 112, second hole 12, third sub-hole 121, fourth sub-hole 122, refractive index adhesive filler 13, fiber 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. The aperture of the first hole 11 is smaller than the aperture of the second hole 12.

[0023] The fiber core 10 has a high refractive index region formed by three first holes 11 and a plurality of second holes 12. In the fiber core 10, the three first holes 11 include a first sub-hole 111 and a second sub-hole 112 disposed on opposite sides of the first sub-hole 111. The first sub-hole 111 is filled with a first filler, and the second sub-hole 112 is filled with a second filler. The refractive index of the first filler is less than that of the second filler. The plurality of second holes 12 include a plurality of third sub-holes 121 and a plurality of fourth sub-holes 122. The plurality of third sub-holes 121 are disposed on one side of the first hole 11, and the plurality of fourth sub-holes 122 are disposed on the other side of the first hole 11. The cladding 20 has a low refractive index region formed by the arrangement of the plurality of first holes 11.

[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 scarce, with the energy of the low-energy region approaching zero.

[0025] Specifically, the diameter of the first hole 11 is smaller than the diameter of the second hole 12. In one embodiment, the diameter d1 of the first hole 11 satisfies the following condition: 0.5μm ≤ d1 ≤ 1.5μm, where d1 can be 0.5μm, 0.6μm, 0.7μm, 0.8μm, 0.9μm, 1μm, 1.1μm, 1.2μm, 1.3μm, 1.4μm, or 1.5μm, etc. The diameter d2 of the second hole 12 satisfies the following condition: 1μm ≤ d2 ≤ 2μm, where d2 can be 1μm, 1.1μm, 1.2μm, 1.3μm, 1.4μm, 1.5μm, 1.6μm, 1.7μm, 1.8μm, 1.9μm, or 2μm, etc.

[0026] In the fiber core 10, a first hole 11 is located at the center of the photonic crystal fiber 1. There are three first holes 11: one first sub-hole 111 and two second sub-holes 112. The first sub-hole 111 is located between the two second sub-holes 112, and the first sub-hole 111 is located at the center of the photonic crystal fiber 1. For example, the first sub-hole 111 is located at the center, and the second sub-holes 112 are located on the left and right sides of the first sub-hole 111. The filling materials in the first sub-hole 111 and the second sub-holes 112 are different. The first filling material fills at least part of the first sub-hole 111, and the second filling material fills at least part of the second sub-holes 112.

[0027] The first filler can be a gas, liquid, or solid, and this embodiment is not limited in this regard; the second filler can also be a gas, liquid, or solid, and this embodiment is not limited in this regard. Specifically, the refractive index of the first filler is less than that of the second filler. In one embodiment, the refractive index of the first filler is 1-1.05, and specific examples of the refractive index of the first filler are 1, 1.01, 1.02, 1.03, 1.04, or 1.05, etc. The refractive index of the second filler is 1.4-1.5, and specific examples of the refractive index of the second filler are 1.4, 1.41, 1.42, 1.43, 1.44, 1.45, 1.46, 1.47, 1.48, 1.49, or 1.5, etc. In another embodiment, the first filler is an air filler, and the material of the air filler is air; the first sub-hole 111 can also be understood as a hollow structure. The second filler is a refractive index adhesive filler 13. The material of the refractive index adhesive filler 13 is refractive index adhesive. For example, the refractive index adhesive filler 13 is poured into the second sub-hole 112 to fill the second sub-hole 112. The refractive index adhesive filler 13 has adhesive properties and can better bond and fix itself in the second sub-hole 112.

[0028] In the fiber core 10, the second hole 12 includes a third sub-hole 121 and a fourth sub-hole 122. The third sub-hole 121 and the fourth sub-hole 122 are located in different positions, respectively on opposite sides of the first hole 11. For example, the first hole 11 is located in the center, and the third sub-hole 121 and the fourth sub-hole 122 are located on the upper and lower sides of the first hole 11, respectively. The number of third sub-holes 121 and fourth sub-holes 122 is equal, ranging from 2 to 6. One third sub-hole 121 corresponds to the gap between two first holes 11, and one fourth sub-hole 122 corresponds to the gap between two first holes 11.

[0029] In the fiber core 10, the diameters of the first sub-hole 111 and the second sub-hole 112 are equal. The distance between the centers of adjacent first sub-holes 111 and second sub-holes 112 is a second distance H2, which satisfies the following condition: 1μm < H2 ≤ 2μm. H2 can be 1μm, 1.1μm, 1.2μm, 1.3μm, 1.4μm, 1.5μm, 1.6μm, 1.7μm, 1.8μm, 1.9μm, or 2μm, etc. The diameters of the third sub-hole 121 and the fourth sub-hole 122 are equal. The distance between the centers of the opposite third sub-hole 121 and the fourth sub-hole 122 is the third distance H3, which satisfies the following condition: 1μm < H3 ≤ 2μm. H3 can be 1μm, 1.1μm, 1.2μm, 1.3μm, 1.4μm, 1.5μm, 1.6μm, 1.7μm, 1.8μm, 1.9μm, or 2μm, etc. The second distance H2 between the centers of the adjacent first sub-hole 111 and the second sub-hole 112 is equal to the third distance H3 between the centers of the opposite third sub-hole 121 and the fourth sub-hole 122.

[0030] In one embodiment, in the fiber core 10, the three first holes 11 are arranged in a preset direction, the plurality of third sub-holes 121 are arranged in the same direction as the preset direction, and the plurality of fourth sub-holes 122 are arranged in the same direction as the preset direction.

[0031] For example, the three first holes 11 are arranged in a horizontal direction, the multiple third sub-holes 121 are also arranged in a horizontal direction, and the multiple fourth sub-holes 122 are also arranged in a horizontal direction. The third sub-holes 121 and the fourth sub-holes 122 are located on the upper and lower sides of the first hole 11, respectively.

[0032] For example, the three first holes 11 are arranged in a vertical direction, the multiple third sub-holes 121 are also arranged in a vertical direction, and the multiple fourth sub-holes 122 are also arranged in a vertical direction. The third sub-holes 121 and the fourth sub-holes 122 are located on the left and right sides of the first hole 11, respectively.

[0033] In one embodiment, in the fiber core 10, there are four of each of the plurality of third sub-holes 121 and the plurality of fourth sub-holes 122. The plurality of third sub-holes 121 and the plurality of fourth sub-holes 122 are arranged in direct correspondence, and the three first holes 11 are staggered with the plurality of third sub-holes 121 and the three first holes 11 are staggered with the plurality of fourth sub-holes 122.

[0034] For example, the three first holes 11 are arranged in a horizontal direction, the four third sub-holes 121 are located above the first holes 11, each third sub-hole 121 is set with a gap between the first holes 11, and the four fourth sub-holes 122 are located below the first holes 11, each fourth sub-hole 122 is set with a gap between the first holes 11, and one third sub-hole 121 and one fourth sub-hole 122 are set directly opposite each other.

[0035] For example, the three first holes 11 are arranged vertically, the four third sub-holes 121 are located to the left of the first holes 11, and each third sub-hole 121 is set with a gap between the first holes 11. The four fourth sub-holes 122 are located to the right of the first holes 11, and each fourth sub-hole 122 is set with a gap between the first holes 11. Furthermore, one third sub-hole 121 and one fourth sub-hole 122 are set in direct correspondence.

[0036] In one embodiment, in the cladding 20, the plurality of first holes 11 are arranged in an array, forming multiple rows, with the first hole 11 in the Mth row corresponding to the first hole 11 in the M+2th row, and the first hole 11 in the Mth row being staggered with the first hole 11 in the M+1th row, where M is a positive integer.

[0037] Specifically, the gap between the first hole 11 in row M and the first hole 11 in row M+1 is set, the gap between the first hole 11 in row M+1 and the first hole 11 in row M+2 is set, and the first hole 11 in row M corresponds exactly to the first hole 11 in row M+2. In other words, the first holes 11 in adjacent rows are staggered.

[0038] In one embodiment, in the cladding 20, the plurality of first holes 11 form multiple columns, the first hole 11 of the Nth column is directly corresponding to the first hole 11 of the N+2th column, and the first hole 11 of the Nth column is alternately arranged with the first hole 11 of the N+1th column, where N is a positive integer.

[0039] Specifically, the gap between the first hole 11 in the Nth column and the first hole 11 in the (N+1)th column is set, the gap between the first hole 11 in the (N+1)th column and the first hole 11 in the (N+2)th column is set, and the first hole 11 in the Nth column corresponds exactly to the first hole 11 in the (N+2)th column. In other words, the first holes 11 in adjacent columns are staggered.

[0040] In the cladding 20, the plurality of first holes 11 are arranged to form a hexagon, and the number of rows I and the number of columns J satisfy the following conditions: 17≤I≤23, 17≤J≤23, where I and J are positive integers.

[0041] The outer periphery of multiple first holes 11 is surrounded to form a hexagon. The number of rows I can be 17, 18, 19, 20, 21, 22, or 23, for example; the number of columns J can be 17, 18, 19, 20, 21, 22, or 23, for example. Optionally, the number of rows I is equal to the number of columns J.

[0042] In one embodiment, in the cladding 20, the distance between the centers of adjacent first holes 11 is a first distance H1, which satisfies the following condition: 1μm < H1 ≤ 2μm. H1 can be specifically 1μm, or 1.1μm, or 1.2μm, or 1.3μm, or 1.4μm, or 1.5μm, or 1.6μm, or 1.7μm, or 1.8μm, or 1.9μm, or 2μm, etc.

[0043] The first distance H1 between the centers of adjacent first holes 11 is equal to the second distance H2 between the centers of adjacent first sub-holes 111 and second sub-holes 112. The first distance H1 between the centers of adjacent first holes 11 is equal to the third distance H3 between the centers of opposite third sub-holes 121 and fourth sub-holes 122.

[0044] Please refer to Figure 5 In one embodiment, for light rays with wavelengths of 1.20 μm to 2.35 μm, the birefringence B of the photonic crystal fiber 1 satisfies the following condition: 5 × 10⁻⁶. -3 ≤B≤17.5×10 -3 .

[0045] For example, the birefringence B of photonic crystal fiber 1 can be 5 × 10⁻⁶. -3 or 6×10 -3 or 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 17.5×10 -3 wait.

[0046] In summary, the photonic crystal fiber 1 provided in this application forms a high refractive index region by setting a first aperture 11 and a second aperture 12 with different aperture sizes, and fillers are set in the first sub-aperture 111 and the second sub-aperture 112, with the refractive index of the first filler being less than that of the second filler. This creates a defect on the photonic crystal fiber 1, resulting in an asymmetric structure and a high birefringence photonic crystal fiber 1, thereby improving the optical transmission performance of the photonic crystal fiber 1.

[0047] 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.

[0048] The optical communication equipment 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 aperture sizes. Fillers are placed in the first and second sub-apertures, and the refractive index of the first filler is less than that of the second filler. This creates a defect on the photonic crystal fiber, resulting in an asymmetric structure and a high birefringence photonic crystal fiber. This improves the optical transmission performance of the photonic crystal fiber and enhances the working performance of the optical communication equipment.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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 hole and a second hole, the diameter of the first hole being smaller than the diameter of the second hole; The fiber core has a high refractive index region formed by three first holes and a plurality of second holes; in the fiber core, the three first holes include a first sub-hole and a second sub-hole disposed on opposite sides of the first sub-hole, the first sub-hole being filled with a first filler and the second sub-hole being filled with a second filler, the refractive index of the first filler being less than that of the second filler, the plurality of second holes include a plurality of third sub-holes and a plurality of fourth sub-holes, the plurality of third sub-holes being disposed on one side of the first hole and the plurality of fourth sub-holes being disposed on the other side of the first hole; the cladding has a low refractive index region formed by the arrangement of a plurality of first holes.

2. The photonic crystal fiber as described in claim 1, characterized in that, The refractive index of the first filler is 1-1.05, and the refractive index of the second filler is 1.4-1.

5.

3. The photonic crystal fiber as described in claim 2, characterized in that, The first filler is an air filler, and the second filler is a refractive index adhesive filler.

4. The photonic crystal fiber as described in claim 1, characterized in that, In the fiber core, the three first holes are arranged in a preset direction, the plurality of third sub-holes are arranged in the same preset direction, and the plurality of fourth sub-holes are arranged in the same preset direction.

5. The photonic crystal fiber as described in claim 4, characterized in that, In the fiber core, there are four of each of the plurality of third sub-holes and the plurality of fourth sub-holes. The plurality of third sub-holes and the plurality of fourth sub-holes are arranged in direct correspondence, and the three first holes are arranged alternately with the plurality of third sub-holes and the three first holes are arranged alternately with the plurality of fourth sub-holes.

6. The photonic crystal fiber as described in claim 1, characterized in that, In the cladding, the plurality of first holes are arranged in an array, forming multiple rows. The first hole in the Mth row corresponds to the first hole in the (M+2)th row, and the first hole in the Mth row is staggered with the first hole in the (M+1)th 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 first holes form multiple columns, with the first hole in the Nth column corresponding to the first hole in the (N+2)th column, and the first hole in the Nth column being staggered with the first 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, The photonic crystal fiber satisfies at least one of the following conditions: The aperture d1 of the first hole satisfies the following condition: 0.5μm≤d1≤1.5μm; The aperture d2 of the second hole satisfies the following condition: 1μm≤d2≤2μm; In the cladding, the distance between adjacent centers of the first hole is a first distance H1, which satisfies the following condition: 1μm < H1 ≤ 2μm.

9. The photonic crystal fiber as described in claim 1, characterized in that, For light rays with wavelengths of 1.20 μm–2.35 μm, the birefringence B of the photonic crystal fiber satisfies the following condition: 5 × 10⁻⁶. -3 ≤B≤17.5×10 -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.

Images