Optical waveguide chip, optical splitter and passive optical network architecture

Abstract

The utility model provides an optical waveguide chip, an optical splitter and a passive optical network architecture, and belongs to the technical field of optical communication. The optical waveguide chip comprises a chip body, an optical waveguide structure, m first optical fibers and n second optical fibers, m is greater than or equal to 1, and n is greater than or equal to 2; the optical waveguide structure is located in the chip body and is provided with m first waveguides close to the first end of the chip body and n second waveguides close to the second end of the chip body, and the first end and the second end of the chip body are the two ends in the light transmission direction; one end of the first optical fiber extends into the chip body and is in butt joint with the first waveguide, the other end of the first optical fiber extends out of the first end of the chip body, one end of the second optical fiber extends into the chip body and is in butt joint with the second waveguide, and the other end of the second optical fiber extends out of the second end of the chip body. According to the invention, the processing procedure of the optical splitter can be simplified, the production efficiency of the optical splitter is improved, and the cost of the optical splitter is reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of optical communication technology, and in particular to an optical waveguide chip, an optical splitter, and a passive optical network architecture. Background Art

[0002] Passive optical network (PON) is a technology that establishes a physical connection between the optical line terminal (OLT) located in the central computer room and the optical network unit (ONU) located on the user side to achieve fiber to the X (FTTX) technology support.

[0003] PON uses a point-to-multipoint (P2MP) communication method, enabling one PON port to support 32, 64, or even 128 users communicating simultaneously. This P2MP communication method is achieved through optical splitters in the optical distribution network (ODN).

[0004] The more common optical splitters are planar lightwave circuit (PLC) optical splitters and fused biconical taper (FBT) optical splitters. PLC optical splitters are widely used due to their uniform light splitting, multiple splitting paths, low cost, and high stability.

[0005] With the rapid development of fiber-optic communication networks, FTTX has evolved from fiber to the home (FTTH) to fiber to the room (FTTR). The market demand for PLC optical splitters in ODN has surged. How to further reduce the cost of PLC optical splitters has become an urgent problem that technicians in this field need to solve. Utility Model Content

[0006] The present disclosure provides an optical waveguide chip, an optical splitter, and a passive optical network architecture, which can simplify the processing steps of the optical splitter, improve the production efficiency of the optical splitter, and thus reduce the cost of the optical splitter.

[0007] In a first aspect, the present disclosure provides an optical waveguide chip, the optical waveguide chip comprising a chip body, an optical waveguide structure, m first optical fibers and n second optical fibers, wherein m is greater than or equal to 1, and n is greater than or equal to 2;

[0008] The optical waveguide structure is located in the chip body and has m first waveguides near a first end of the chip body and n second waveguides near a second end of the chip body, wherein the first end and the second end of the chip body are two ends along a light transmission direction;

[0009] One end of the first optical fiber extends into the chip body and docks with the first waveguide, and the other end of the first optical fiber extends from the first end of the chip body. One end of the second optical fiber extends into the chip body and docks with the second waveguide, and the other end of the second optical fiber extends from the second end of the chip body.

[0010] In the solution disclosed herein, the optical waveguide chip integrates not only an optical waveguide structure but also at least one first optical fiber and multiple second optical fibers. The at least one first optical fiber can serve as an input optical fiber, and the multiple second optical fibers can serve as output optical fibers. Therefore, when this optical waveguide chip is used in an optical splitter, only one section of the optical waveguide chip is required, eliminating the need for an input and output optical fiber arrays. This results in a single-segment optical splitter. Compared to a three-segment optical splitter, this single-segment optical splitter reduces the number of polished surfaces and simplifies the manufacturing process, thereby improving the production efficiency and reducing production costs.

[0011] Furthermore, in processing the optical waveguide chip, the first optical fiber and the second optical fiber can be integrated on the wafer, and then the wafer can be cut into multiple optical waveguide chips. This processing method is conducive to the mass production of optical waveguide chips, further improving the production efficiency of the optical splitter and further reducing the production cost.

[0012] Moreover, the m first optical fibers are docked with the m first waveguides one by one, and the n second optical fibers are docked with the n second waveguides one by one. Compared with simultaneous docking, docking one by one is more conducive to controlling the optical coupling accuracy between the first optical fiber and the first waveguide, as well as the optical coupling accuracy between the second optical fiber and the second waveguide.

[0013] In a possible implementation, the chip body includes a chip substrate, the optical waveguide structure is located on a surface of the chip substrate, and the surface of the chip substrate has m first optical fiber grooves and n second optical fiber grooves;

[0014] The first optical fiber groove extends from the first end of the chip substrate to the optical coupling end of the first waveguide, and the second optical fiber groove extends from the second end of the chip substrate to the optical coupling end of the second waveguide, and the first end and the second end of the chip substrate are two ends along the light transmission direction;

[0015] The first optical fiber is fixed in the first optical fiber groove and docked with the first waveguide, and the second optical fiber is fixed in the second optical fiber groove and docked with the second waveguide;

[0016] The chip body further includes a cover plate, which covers the optical waveguide structure, the m first optical fiber grooves and the n second optical fiber grooves and is fixed to the chip substrate.

[0017] In the solution shown in the present disclosure, a first optical fiber groove and a second optical fiber groove are opened on the surface of the chip substrate, which is easy to implement. Fixing the first optical fiber in the first optical fiber groove and fixing the second optical fiber in the second optical fiber groove is also easier to operate, for example, facilitating gluing and welding fixation.

[0018] In a possible implementation, the first optical fiber groove has a guide structure at the first end of the chip substrate, and the second optical fiber groove has a guide structure at the second end of the chip substrate.

[0019] In the solution disclosed herein, the groove width of the guide structure of the first optical fiber groove is relatively large, which facilitates the insertion of the first optical fiber into the first optical fiber groove. The groove width of the guide structure of the second optical fiber groove is also relatively large, which also facilitates the insertion of the second optical fiber into the second optical fiber groove, further improving the production efficiency of the optical waveguide chip.

[0020] In a possible implementation, the cross-section of the first optical fiber groove is arc-shaped, U-shaped, V-shaped, or trapezoidal, and the cross-section of the second optical fiber groove is arc-shaped, U-shaped, V-shaped, or trapezoidal.

[0021] In a possible implementation, the chip body has m first optical fiber holes and n second optical fiber holes;

[0022] The first optical fiber hole extends from the end face of the first end of the chip body to the optical coupling end of the first waveguide, and the second optical fiber hole extends from the end face of the second end of the chip body to the optical coupling end of the second waveguide;

[0023] The first optical fiber is fixed in the first optical fiber hole and docked with the first waveguide, and the second optical fiber is fixed in the second optical fiber hole and docked with the second waveguide.

[0024] In a possible implementation, the first optical fiber hole has a guide structure at the first end of the chip body, and the second optical fiber hole has a guide structure at the second end of the chip body.

[0025] In the solution disclosed herein, the aperture of the guide structure of the first optical fiber hole is larger, which facilitates the first optical fiber to extend into the first optical fiber hole, and the aperture of the guide structure of the second optical fiber hole is also larger, which facilitates the second optical fiber to extend into the second optical fiber hole, thereby helping to speed up the production efficiency of the optical waveguide chip.

[0026] In a possible implementation, the cross-sectional shape of the first optical fiber hole is circular, and the axial centerline of the first optical fiber hole is collinear with the axial centerline of the first waveguide;

[0027] The cross-sectional shape of the second optical fiber hole is circular, and the axial center line of the second optical fiber hole is collinear with the axial center line of the second waveguide.

[0028] In the solution disclosed herein, the axial centerline of the first fiber hole is collinear with the axial centerline of the first waveguide, which facilitates controlling the alignment accuracy of the first fiber inserted into the first fiber hole and the first waveguide, thereby enhancing the optical coupling effect. Similarly, the axial centerline of the second fiber hole is collinear with the axial centerline of the second waveguide, which also facilitates controlling the alignment accuracy of the second fiber inserted into the second fiber hole and the second waveguide, thereby enhancing the optical coupling effect.

[0029] In one possible implementation, the chip body has a first groove perpendicular to the light transmission direction at the optical coupling ends of the m first waveguides, and has a second groove perpendicular to the light transmission direction at the optical coupling ends of the n second waveguides, the first groove is used to expose the optical coupling end of the first waveguide, and the second groove is used to expose the optical coupling end of the second waveguide.

[0030] In the solution shown in the present disclosure, a first groove and a second groove are provided on the surface of the chip substrate of the chip body, which is conducive to extending the grinding tool into the first groove to grind the optical coupling end of the first waveguide, and extending the grinding tool into the second groove to grind the optical coupling end of the second waveguide, so as to improve the flatness of the optical coupling end of the first waveguide and the flatness of the optical coupling end of the second waveguide.

[0031] In a second aspect, an optical splitter is provided, comprising a housing and the optical waveguide chip according to the first aspect, wherein the housing has at least one first optical interface and at least one second optical interface;

[0032] The optical waveguide chip is located in the housing, and the m first optical fibers extend from the ends of the chip body and extend into the at least one first optical interface, and the n second optical fibers extend from the ends of the chip body and extend into the at least one second optical interface.

[0033] In a third aspect, a passive optical network architecture is provided, which includes a trunk optical fiber, a branch optical fiber and the optical splitter described in the second aspect, wherein the trunk optical fiber is connected to the first optical interface of the optical splitter to dock with the first optical fiber, and the branch optical fiber is connected to the second optical interface of the optical splitter to dock with the second optical fiber. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic structural diagram of an optical waveguide chip provided by an exemplary embodiment of the present disclosure;

[0035] Figure 2 is a schematic structural diagram of a chip body provided by an exemplary embodiment of the present disclosure;

[0036] Figure 3 This is a schematic diagram of an exemplary embodiment of the present disclosure before a cover plate is covered on a chip body;

[0037] Figure 4 is a schematic structural diagram of an optical waveguide chip provided by an exemplary embodiment of the present disclosure;

[0038] Figure 5 is a schematic structural diagram of a chip body provided by an exemplary embodiment of the present disclosure;

[0039] Figure 6 is a schematic structural diagram of a chip body provided by an exemplary embodiment of the present disclosure;

[0040] Figure 7 is a schematic structural diagram of a chip body provided by an exemplary embodiment of the present disclosure;

[0041] Figure 8 is a schematic diagram of a first optical fiber and a second optical fiber provided by an exemplary embodiment of the present disclosure before being inserted into a chip body;

[0042] Figure 9 is a schematic structural diagram of a chip body provided by an exemplary embodiment of the present disclosure;

[0043] Figure 10 is a schematic structural diagram of a chip body provided by an exemplary embodiment of the present disclosure;

[0044] Figure 11 FIG. 4 is a structural diagram of a PON architecture provided by an exemplary embodiment of the present disclosure.

[0045] Description of Reference Numerals

[0046] 1. Chip body; 11. Chip substrate; 12. Cover plate; 13. First optical fiber hole; 14. Second optical fiber hole; 111. First optical fiber groove; 112. Second optical fiber groove; 113. First groove; 114. Second groove; 2. Optical waveguide structure; 21. First waveguide; 22. Second waveguide; 3. First optical fiber; 4. Second optical fiber.

[0047] 100, housing; 101, first optical interface; 102, second optical interface; 200, optical waveguide chip; 300, trunk optical fiber; 400, branch optical fiber. DETAILED DESCRIPTION

[0048] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0049] The embodiments of the present disclosure relate to an optical waveguide chip, specifically a planar optical waveguide chip, wherein a planar lightwave circuit (PLC), that is, an optical waveguide, is located in a plane.

[0050] Current PLC optical splitters typically consist of an input fiber array (FA), an optical waveguide chip, and an output fiber array. The input fiber array is coupled to the first end of the optical waveguide chip, while the output fiber array is coupled to the second end of the optical waveguide chip, making the PLC optical splitter a three-stage PLC optical splitter. This three-stage PLC optical splitter requires numerous assembly steps and is cumbersome to operate. For example, during the coupling process, the input fiber array, the output fiber array, and the optical waveguide chip require polishing of four optical coupling surfaces: the optical coupling surface of the input fiber array, the optical coupling surface of the optical waveguide at the first end of the optical waveguide chip, the optical coupling surface of the optical waveguide at the second end of the optical waveguide chip, and the optical coupling surface of the output fiber array. Furthermore, during the coupling process, aligning the multiple output fibers of the output fiber array with the multiple optical waveguides at the second end of the optical waveguide chip is challenging.

[0051] Therefore, the current three-stage PLC optical splitter is difficult to meet the market demand for PLC optical splitters due to the complicated assembly process. Also, due to the complicated process, the production cost is difficult to further reduce.

[0052] To this end, this embodiment provides an optical waveguide chip, such as Figure 1 As shown, it is a schematic diagram of the structure of the optical waveguide chip. Figure 1As shown, the optical waveguide chip includes a chip body 1 and an optical waveguide structure 2. The optical waveguide structure 2 is a structure including multiple optical waveguides. The optical waveguide is a medium that guides light waves (also called optical signals) to propagate therein, also known as a dielectric optical waveguide. The optical waveguide in this embodiment is integrated into the chip, so it belongs to an integrated optical waveguide, so continue to refer to Figure 1 As shown, the optical waveguide structure 2 is located in the chip body 1. For example, the optical waveguide structure 2 can be arranged in the chip body 1 using plasma enhanced chemical vapor deposition (PECVD), ion exchange, or femtosecond laser direct writing waveguide technology, such as being arranged on the surface of the chip substrate 11 of the chip body 1.

[0053] It should be pointed out that Figure 1 The lighter grey lines represent the interior of the chip body 1 and are invisible lines, while the darker black lines represent visible lines.

[0054] In one example, since the optical waveguide chip realizes light splitting or light combining through the optical waveguide structure 2, reference Figure 1 As shown, the optical waveguide structure 2 includes m first waveguides 21 and n second waveguides 22, wherein the m first waveguides 21 are located near the first end of the chip body 1, and the n second waveguides 22 are located near the second end of the chip body 1. Figure 1 As shown, m first waveguides 21 and n second waveguides 22 are distributed left and right along the light transmission direction, the m first waveguides 21 are arranged on the left side of the chip body 1 , and the n second waveguides 22 are located on the right side of the chip body 1 .

[0055] Here, m is an integer greater than or equal to 1, and n is an integer greater than or equal to 2. In the figure, m=1 and n=4 are used as examples. Of course, m can also be two or more. Generally, m is smaller than n, so that m optical signals can be divided into n optical signals.

[0056] In one example, since the optical waveguide structure 2 needs to be connected to the optical fiber (also called optical coupling), then, refer to Figure 1 As shown, the optical waveguide chip also includes a first optical fiber 3 and a second optical fiber 4, wherein the first optical fiber 3 is used to connect with the first waveguide 21, and the second optical fiber 4 is used to connect with the second waveguide 22. Therefore, the number of first optical fibers 3 is equal to the number of first waveguides 21, both being m, and the m first optical fibers 3 are connected one-to-one with the m first waveguides 21. The number of second optical fibers 4 is equal to the number of second waveguides 22, both being n, and the n second optical fibers 4 are connected one-to-one with the n second waveguides 22.

[0057] For example, reference Figure 1As shown, one end of the first optical fiber 3 extends into the chip body 1 and connects to the first waveguide 21, and the other end of the first optical fiber 3 extends out of the first end of the chip body 1 for external connection, such as connecting to the trunk optical fiber (refer to Figure 11 As shown), one end of the second optical fiber 4 extends into the chip body 1 and docks with the second waveguide 22, and the other end of the second optical fiber 4 extends from the second end of the chip body 1 for external connection, such as docking with the branch optical fiber (reference Figure 11 shown).

[0058] This optical waveguide chip, which integrates one end of the first optical fiber 3 and one end of the second optical fiber 4 into the chip body 1, eliminates the fiber array (FA) where the first optical fiber 3 and the second optical fiber 4 are located, retaining one section of the optical waveguide chip and making the PLC optical splitter a single-segment PLC optical splitter. This single-segment PLC optical splitter eliminates the coupling between the optical fiber array and the optical waveguide chip, reduces the number of polished surfaces, simplifies the assembly process of the PLC optical splitter, and helps improve production efficiency and reduce production costs.

[0059] Furthermore, in the processing of optical waveguide chips, the optical fiber and the waveguide can be docked at the wafer level, that is, the first optical fiber 3 is docked with the first waveguide 21, and the second optical fiber 4 is docked with the second waveguide 22 on the wafer. After the docking is completed, the chips are sliced and cut into multiple optical waveguide chips, which is conducive to the mass production of optical waveguide chips, further improving production efficiency and reducing production costs.

[0060] Moreover, the m first optical fibers 3 are docked with the m first waveguides 21 one by one, and the n second optical fibers 4 are docked with the n second waveguides 22 one by one. Compared with simultaneous docking, docking one by one is beneficial to controlling the optical coupling accuracy between the first optical fiber and the first waveguide 21, as well as the optical coupling accuracy between the second optical fiber 4 and the second waveguide 22.

[0061] like Figure 3 And refer to Figure 4 As shown, the chip body 1 includes a chip substrate 11 and a cover plate 12, the optical waveguide structure 2 is located on the surface of the chip substrate 11, and the cover plate 12 is covered on the surface of the chip substrate 11 and covers the optical waveguide structure 2, wherein the chip substrate 11 and the cover plate 12 have the same shape and equal area.

[0062] In order to achieve that a portion of the first optical fiber 3 and the second optical fiber 4 extends into the chip body 1, a corresponding method may be to refer to Figure 2As shown, the surface of the chip substrate 11 has a first fiber groove 111 and a second fiber groove 112. The first fiber groove 111 is used to insert the first optical fiber 3, and the second fiber groove 112 is used to insert the second optical fiber 4. Therefore, the number of first fiber grooves 111 is equal to the number of first optical fibers 3, both being m, and the number of second fiber grooves 112 is equal to the number of second optical fibers 4, both being n.

[0063] Continue to refer Figure 2 As shown, the first optical fiber groove 111 and the second optical fiber groove 112 are both strip-shaped, and the strip direction is consistent with the light transmission direction. Moreover, the first optical fiber groove 111 extends from the first end of the chip substrate 11 to the optical coupling end of the first waveguide 21, and the second optical fiber groove 112 extends from the second end of the chip substrate 11 to the optical coupling end of the second waveguide 22.

[0064] The first optical fiber slots 111 and the first waveguides 21 are opposite to each other in the light transmission direction, and the second optical fiber slots 112 and the second waveguides 22 are opposite to each other in the light transmission direction.

[0065] In this way, a portion of each first optical fiber 3 can be located in a first optical fiber groove 111 to dock with the first waveguide 21 corresponding to the first optical fiber groove 111, and a portion of each second optical fiber 4 can be located in a second optical fiber groove 112 to dock with the second waveguide 22 corresponding to the second optical fiber groove 112.

[0066] All first optical fibers 3 are arranged in the first optical fiber groove 111, and all second optical fibers 4 are arranged in the second optical fiber groove 112. After the first optical fibers 3 are connected to the first waveguide 21 and the second optical fibers 4 are connected to the second waveguide 22, the cover plate 12 is covered and fixed on the surface of the chip substrate 11.

[0067] In one example, the cross-sectional shape of the first optical fiber groove 111 can be U-shaped, V-shaped, arc-shaped, or trapezoidal, and similarly, the cross-sectional shape of the second optical fiber groove 112 can also be U-shaped, V-shaped, arc-shaped, or trapezoidal, etc. For example, Figure 2 As shown, the cross-section of the first optical fiber groove 111 and the second optical fiber groove 112 is arc-shaped. Figure 5 As shown, the cross-section of the first optical fiber groove 111 and the second optical fiber groove 112 is trapezoidal. Figure 6 As shown, the cross-section of the first optical fiber groove 111 and the second optical fiber groove 112 is triangular.

[0068] In one example, in order to smoothly insert the first optical fiber 3 into the first optical fiber groove 111 and smoothly insert the second optical fiber 4 into the second optical fiber groove 112, the first optical fiber groove 111 and the second optical fiber groove 112 are provided with guide structures, for example, Figure 7As shown, the first optical fiber groove 111 has a guide structure at the first end of the chip substrate 11 , and the second optical fiber groove 112 has a guide structure at the second end of the chip substrate 11 .

[0069] The guide structure is formed by a stepped groove. For example, the first optical fiber groove 111 is a stepped groove, and the groove width of the first optical fiber groove 111 at the first end of the chip substrate 11 is larger. The second optical fiber groove 112 is a stepped groove, and the groove width of the second optical fiber groove 112 at the second end of the chip substrate 11 is larger.

[0070] In this way, under the action of the guiding structure, the first optical fiber 3 can smoothly extend into the first optical fiber groove 111 , and the second optical fiber 4 can smoothly extend into the second optical fiber groove 112 .

[0071] It should be pointed out that before inserting the first optical fiber 3 into the first optical fiber groove 111, it is necessary to first strip off the coating layer of the first optical fiber 3 to expose the core of the first optical fiber 3, and then pre-process the core of the first optical fiber 3 to make the optical coupling end of the core of the first optical fiber 3 smooth and flat, and then insert the core of the first optical fiber 3 into the first optical fiber groove 111 and dock with the first waveguide 21.

[0072] Similarly, before inserting the second optical fiber 4 into the second optical fiber groove 112, it is necessary to first strip off the coating layer of the second optical fiber 4 to expose the core of the second optical fiber 4, and then pre-process the core of the second optical fiber 4 to make the optical coupling end of the core of the second optical fiber 4 smooth and flat, and then insert the core of the second optical fiber 4 into the second optical fiber groove 112 and dock with the second waveguide 22.

[0073] In one example, the optical fiber and the waveguide can be fixed by optical adhesive or welding to achieve the effect of refractive index matching and bonding the optical fiber, thereby improving return loss performance and reliability.

[0074] For example, taking the docking of the first optical fiber 3 and the first waveguide 21 as an example, optical adhesive can be applied to the optical coupling end points of the first optical fiber 3 and the optical coupling end points of the first waveguide 21 to ensure stable docking of the first optical fiber 3 and the first waveguide 21. Glue can also be applied to the walls of the first optical fiber groove 111 to secure the first optical fiber 3 in the first optical fiber groove 111. Alternatively, glue can be applied to both the optical coupling end points of the first optical fiber 3 and the optical coupling end points of the first waveguide 21, as well as the walls of the first optical fiber groove 111. The docking method for the second optical fiber 4 and the second waveguide 22 can be referred to the above description and will not be repeated here.

[0075] In another example, the first optical fiber groove 111 can be replaced by the first optical fiber hole 13, and the second optical fiber groove 112 can be replaced by the second optical fiber hole 14. Figure 8As shown, the chip body 1 has m first optical fiber holes 13 and n second optical fiber holes 14, wherein the first optical fiber hole 13 extends from the end face of the first end of the chip body 1 to the optical coupling end of the first waveguide 21, and the second optical fiber hole 14 extends from the end face of the second end of the chip body 1 to the optical coupling end of the second waveguide 22.

[0076] The aperture of the first optical fiber hole 13 matches the diameter of the core of the first optical fiber 3 , and the aperture of the second optical fiber hole 14 matches the diameter of the core of the second optical fiber 4 . For example, the apertures of the first optical fiber hole 13 and the second optical fiber hole 14 are both about 125 μm.

[0077] In this way, one end of each first optical fiber 3 can be extended into a first optical fiber hole 13 and docked with a first waveguide 21 corresponding to the first optical fiber hole 13, and one end of each second optical fiber 4 can be extended into a second optical fiber hole 14 and docked with a second waveguide 22 corresponding to the second optical fiber hole 14.

[0078] The chip body 1 may be a chip body including a chip substrate 11 and a cover plate 12 . Then, a portion of the first optical fiber hole 13 is opened on the chip substrate 11 , and another portion is opened on the cover plate 12 .

[0079] In one example, in order to enable the first optical fiber 3 extending into the first optical fiber hole 13 to dock with the first waveguide 21, the axial center line (also called the geometric center line) of the first optical fiber hole 13 with a circular cross-section and the axial center line (also called the geometric center line) of the first waveguide 21 are on a straight line.

[0080] Likewise, the axial centerline (also referred to as the geometric centerline) of the second optical fiber hole 14 having a circular cross-sectional shape and the axial centerline (also referred to as the geometric centerline) of the second waveguide 22 are aligned.

[0081] The axial centerline of the first optical fiber hole 13 is collinear with the axial centerline of the first waveguide 21, and the axial centerline of the second optical fiber hole 14 is collinear with the axial centerline of the second waveguide 22, which is beneficial to improving the alignment accuracy of the first optical fiber 3 and the first waveguide 21, and the alignment accuracy of the second optical fiber 4 and the second waveguide 22.

[0082] In order to allow the first optical fiber 3 to smoothly extend into the first optical fiber hole 13 and the second optical fiber 4 to smoothly extend into the second optical fiber hole 14, the first optical fiber hole 13 and the second optical fiber hole 14 are provided with guide structures. Figure 9 As shown, the first optical fiber hole 13 has a guide structure at the first end of the chip body 1 , and the second optical fiber hole 14 has a guide structure at the second end of the chip body 1 .

[0083] Among them, the guiding structure is formed by a stepped hole. For example, the first optical fiber hole 13 is a stepped hole, and the aperture of the first optical fiber hole 13 at the first end of the chip body 1 is larger. The second optical fiber hole 14 is a stepped hole, and the aperture of the second optical fiber hole 14 at the second end of the chip body 1 is larger.

[0084] In this way, under the action of the guiding structure, the first optical fiber 3 can smoothly extend into the first optical fiber hole 13 , and the second optical fiber 4 can smoothly extend into the second optical fiber hole 14 .

[0085] It should be pointed out that before inserting the first optical fiber 3 into the first optical fiber hole 13, it is necessary to first strip off the coating layer of the first optical fiber 3 to expose the core of the first optical fiber 3, and then pre-process the core of the first optical fiber 3 to make the optical coupling end of the core of the first optical fiber 3 smooth and flat, and then insert the core of the first optical fiber 3 into the first optical fiber hole 13 and dock with the first waveguide 21.

[0086] Similarly, before inserting the second optical fiber 4 into the second optical fiber hole 14, it is necessary to first strip off the coating of the second optical fiber 4 to expose the core of the second optical fiber 4, and then pre-process the core of the second optical fiber 4 to make the optical coupling end of the core of the second optical fiber 4 smooth and flat, and then insert the core of the second optical fiber 4 into the second optical fiber hole 14 and dock with the second waveguide 22.

[0087] In one example, the optical fiber and the waveguide can be fixed by optical adhesive or welding to achieve the effect of refractive index matching and bonding the optical fiber, thereby improving return loss performance and reliability.

[0088] For example, using the docking of the first optical fiber 3 and the first waveguide 21 as an example, optical adhesive can be applied to the optical coupling end of the first optical fiber 3 and the optical coupling end of the first waveguide 21 to ensure stable docking of the first optical fiber 3 and the first waveguide 21. Glue can also be applied to the wall of the second optical fiber hole 14 to secure the first optical fiber 3 in the second optical fiber hole 14. Alternatively, glue can be applied to both the optical coupling end of the first optical fiber 3 and the optical coupling end of the first waveguide 21, as well as the wall of the second optical fiber hole 14. The docking method for the second optical fiber 4 and the second waveguide 22 can be referred to as described above and will not be repeated here.

[0089] In one example, in order to facilitate the grinding of the optical coupling end of the first waveguide 21 and the optical coupling end of the second waveguide 22, correspondingly, as shown in FIG. Figure 10 As shown, the chip body 1 has a first groove 113 perpendicular to the light transmission direction at the optical coupling end of the m first waveguides 21, and the chip body 1 also has a second groove 114 perpendicular to the light transmission direction at the optical coupling end of the n second waveguides 22, wherein the first groove 113 is used to expose the optical coupling end of the first waveguide 21, and the second groove 114 is used to expose the optical coupling end of the second waveguide 22.

[0090] As described above, the chip body 1 includes a chip substrate 11 and a cover plate 12, and the optical waveguide structure 2 is located on the surface of the chip substrate 11. Figure 10 As shown, the first groove 113 and the second groove 114 are both provided on the surface of the chip substrate 11 .

[0091] Continue to refer Figure 10 As shown, a grinding tool (such as a precision grinding wheel) can be inserted into the first groove 113 to grind the optical coupling ends of the m first waveguides 21, and the grinding tool can be inserted into the second groove 114 to grind the optical coupling ends of the n second waveguides 22. This can improve the flatness of the optical coupling ends of the first waveguides 21 and the second waveguides 22, reduce the insertion loss and return loss of the first optical fiber 3 and the first waveguide 21, and reduce the insertion loss and return loss of the second optical fiber 4 and the second waveguide 22.

[0092] In the disclosed embodiment, the optical waveguide chip integrates not only the optical waveguide structure 2 but also at least one first optical fiber 3 and multiple second optical fibers 4. The at least one first optical fiber 3 can serve as an input optical fiber, and the multiple second optical fibers 4 can serve as output optical fibers. Therefore, when used in an optical splitter, only one section of the optical waveguide chip is required, eliminating the need for an input and output optical fiber arrays. This makes the optical splitter a single-section optical splitter. Compared to a three-section optical splitter, this single-section optical splitter can reduce the number of polished surfaces and simplify the manufacturing process of the optical splitter, thereby improving the production efficiency of the optical splitter and reducing production costs.

[0093] Furthermore, in the processing of optical waveguide chips, the first optical fiber 3 and the second optical fiber 4 can be integrated on the wafer, and then the wafer can be cut into multiple optical waveguide chips. This processing method is conducive to the mass production of optical waveguide chips, further improving the production efficiency of the optical splitter and further reducing the production cost.

[0094] Moreover, the m first optical fibers 3 are docked with the m first waveguides 21 one by one, and the n second optical fibers 4 are docked with the n second waveguides 22 one by one. Compared with simultaneous docking, docking one by one is beneficial to controlling the optical coupling accuracy between the first optical fiber and the first waveguide 21, as well as the optical coupling accuracy between the second optical fiber 4 and the second waveguide 22.

[0095] The embodiment of the present disclosure also provides an optical splitter, which may be a PLC optical splitter, such as Figure 11As shown, the optical waveguide chip 200 includes a housing 100 and the aforementioned optical waveguide chip 200, wherein the housing 100 has at least one first optical interface 101 and at least one second optical interface 102. The optical waveguide chip 200 is located in the housing 100, and the m first optical fibers 3 each extend from the end of the chip body 1 and extend into the at least one first optical interface 101, and the n second optical fibers 4 each extend from the end of the chip body 1 and extend into the at least one second optical interface 102.

[0096] The number of first optical interfaces 101 may be equal to the number of first optical fibers 3, and one first optical fiber 3 extends into one first optical interface 101. Alternatively, the number of first optical interfaces 101 may be less than the number of first optical fibers 3, and one or more first optical fibers 3 extend into one first optical interface 101. For example, two first optical fibers 3 each extend into one first optical interface 101, and the first optical interface 101 may have two sub-interfaces, with the two first optical fibers 3 extending into the two sub-interfaces, respectively.

[0097] Similarly, the number of second optical interfaces 102 can be equal to the number of second optical fibers 4, and then one second optical fiber 4 extends into one second optical interface 102. Alternatively, the number of second optical interfaces 102 is less than the number of second optical fibers 4, and then one or more second optical fibers 4 extend into one second optical interface 102. For example, two second optical fibers 4 each extend into one second optical interface 102, and the second optical interface 102 can have two sub-interfaces, and the two second optical fibers 4 extend into the two sub-interfaces respectively.

[0098] The present disclosure also provides a passive optical network (PON) architecture. Figure 11 As shown, the PON architecture includes a trunk optical fiber 300, a branch optical fiber 400 and the optical splitter described above, wherein the trunk optical fiber 300 is connected to the first optical interface 101 of the optical splitter to connect with the first optical fiber 3, and the branch optical fiber 400 is connected to the second optical interface 102 of the optical splitter to connect with the second optical fiber 4.

[0099] The terms used in the embodiments of the present disclosure are only used to explain the embodiments of the present disclosure and are not intended to limit the present disclosure. Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should have the ordinary meaning understood by people with ordinary skills in the field to which the present disclosure belongs. The words "first", "second" and similar terms used in this disclosure specification and claims do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "a" do not indicate a quantitative limitation, but rather indicate the presence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before "include" or "comprises" include the elements or objects listed after "include" or "comprises" and their equivalents, and do not exclude other elements or objects. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. "Multiple" refers to two or more, unless otherwise clearly defined.

[0100] The above descriptions are merely optional embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. An optical waveguide chip, characterized in that: The optical waveguide chip comprises a chip body (1), an optical waveguide structure (2), m first optical fibers (3) and n second optical fibers (4), wherein m is greater than or equal to 1 and n is greater than or equal to 2; The optical waveguide structure (2) is located in the chip body (1) and has m first waveguides (21) close to the first end of the chip body (1), and n second waveguides (22) close to the second end of the chip body (1), wherein the first end and the second end of the chip body (1) are two ends along the light transmission direction; One end of the first optical fiber (3) extends into the chip body (1) and docks with the first waveguide (21), and the other end extends out of the first end of the chip body (1); one end of the second optical fiber (4) extends into the chip body (1) and docks with the second waveguide (22), and the other end extends out of the second end of the chip body (1).

2. The optical waveguide chip according to claim 1, wherein The chip body (1) comprises a chip substrate (11), the optical waveguide structure (2) is located on a surface of the chip substrate (11), and the surface of the chip substrate (11) has m first optical fiber grooves (111) and n second optical fiber grooves (112); The first optical fiber groove (111) extends from the first end of the chip substrate (11) to the optical coupling end of the first waveguide (21), and the second optical fiber groove (112) extends from the second end of the chip substrate (11) to the optical coupling end of the second waveguide (22), and the first end and the second end of the chip substrate (11) are two ends along the light transmission direction; The first optical fiber (3) is fixed in the first optical fiber groove (111) and docked with the first waveguide (21); the second optical fiber (4) is fixed in the second optical fiber groove (112) and docked with the second waveguide (22); The chip body (1) further comprises a cover plate (12), the cover plate (12) covering the optical waveguide structure (2), the m first optical fiber grooves (111) and the n second optical fiber grooves (112), and being fixed to the chip substrate (11).

3. The optical waveguide chip according to claim 2, wherein: The first optical fiber groove (111) has a guide structure at the first end of the chip substrate (11), and the second optical fiber groove (112) has a guide structure at the second end of the chip substrate (11).

4. The optical waveguide chip according to claim 2 or 3, characterized in that The cross-section of the first optical fiber groove (111) is in an arc shape, a U shape, a V shape or a trapezoidal shape, and the cross-section of the second optical fiber groove (112) is in an arc shape, a U shape, a V shape or a trapezoidal shape.

5. The optical waveguide chip according to claim 1, wherein The chip body (1) has m first optical fiber holes (13) and n second optical fiber holes (14); The first optical fiber hole (13) extends from the end face of the first end of the chip body (1) to the optical coupling end of the first waveguide (21), and the second optical fiber hole (14) extends from the end face of the second end of the chip body (1) to the optical coupling end of the second waveguide (22); The first optical fiber (3) is fixed in the first optical fiber hole (13) and docked with the first waveguide (21); the second optical fiber (4) is fixed in the second optical fiber hole (14) and docked with the second waveguide (22).

6. The optical waveguide chip according to claim 5, wherein: The first optical fiber hole (13) has a guide structure at the first end of the chip body (1), and the second optical fiber hole (14) has a guide structure at the second end of the chip body (1).

7. The optical waveguide chip according to claim 5 or 6, characterized in that: The cross-sectional shape of the first optical fiber hole (13) is circular, and the axial center line of the first optical fiber hole (13) is collinear with the axial center line of the first waveguide (21); The cross-sectional shape of the second optical fiber hole (14) is circular, and the axial center line of the second optical fiber hole (14) is collinear with the axial center line of the second waveguide (22).

8. The optical waveguide chip according to any one of claims 1 to 7, characterized in that: The chip body (1) has a first groove (113) perpendicular to the light transmission direction at the light coupling ends of the m first waveguides (21), and has a second groove (114) perpendicular to the light transmission direction at the light coupling ends of the n second waveguides (22), wherein the first groove (113) is used to expose the light coupling ends of the first waveguides (21), and the second groove (114) is used to expose the light coupling ends of the second waveguides (22).

9. An optical splitter, characterized in that: The optical splitter comprises a housing (100) and the optical waveguide chip (200) according to any one of claims 1 to 8, wherein the housing (100) has at least one first optical interface (101) and at least one second optical interface (102); The optical waveguide chip (200) is located in the housing (100), and the ends of the m first optical fibers (3) extending from the chip body (1) extend to the at least one first optical interface (101), and the ends of the n second optical fibers (4) extending from the chip body (1) extend to the at least one second optical interface (102).

10. A passive optical network architecture, characterized in that: The passive optical network architecture comprises a trunk optical fiber (300), a branch optical fiber (400) and the optical splitter according to claim 9, wherein the trunk optical fiber (300) is connected to a first optical interface (101) of the optical splitter to be docked with the first optical fiber (3), and the branch optical fiber (400) is connected to a second optical interface (102) of the optical splitter to be docked with the second optical fiber (4).

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