Mode spot converter and chip package assembly

Abstract

The utility model provides a kind of mode spot converter and chip packaging assembly, including glass substrate, main mode spot conversion waveguide and alignment coupling waveguide, main mode spot conversion waveguide extends along first direction, the first end of main mode spot conversion waveguide is used to connect service optical fiber channel in fiber array, the second end of main mode spot conversion waveguide is used to connect photonic integrated chip.Alignment coupling waveguide is U-shaped, the first end and the second end of alignment coupling waveguide are located in the side end surface of glass substrate, and respectively located in the two sides of main mode spot conversion waveguide along second direction, for connecting alignment optical fiber channel in fiber array.Second direction is perpendicular to first direction and is located in the plane where main mode spot conversion waveguide is located.At least part waveguide section of alignment coupling waveguide is in different plane with the plane where main mode spot conversion waveguide is located.Solved the problem that fiber array channel number is difficult to reduce in prior art, and the risk of waveguide same layer intersection and then improving optical crosstalk is caused.

Description

Technical Field

[0001] This utility model relates to the field of silicon photonic integrated chips, and in particular to a speckle converter and chip packaging component. Background Technology

[0002] With the expanding applications of silicon photonic integrated chips in optical communication, data center interconnects, optical switching, optical computing, and sensing systems, efficient coupling between fiber arrays and photonic integrated chips has become a critical issue in packaging. The mode field size of the optical fiber typically differs from that of the edge coupler of the photonic integrated chip, and direct coupling can easily lead to significant mode field mismatch loss. To mitigate this mismatch problem, existing technologies typically incorporate a mode-conversion waveguide chip between the fiber array and the photonic integrated chip. This allows the optical signal to gradually convert from the fiber-side mode field to a mode field suitable for reception by the photonic integrated chip's edge coupler during propagation, or vice versa, converting the mode field from the chip side to the fiber side.

[0003] Existing mode-changing optical waveguide chips can be fabricated using SiO2, SiO2 / SiN composite materials, or other materials suitable for waveguide formation, and can be fabricated using planar micro / nano fabrication processes such as photolithography, thin film deposition, and etching. For example, a set of independent U-shaped coupled waveguide pairs can be arranged on both sides of the main mode-changing waveguide array of the mode-changing optical waveguide chip. However, in such a wiring structure, because each U-shaped coupled waveguide pair is independent, each pair requires one input port and one output port, necessitating at least four additional alignment fiber ports on both sides. This increases the number of fiber array channels, as well as the cost, device width, and packaging complexity. Furthermore, this structure cannot support direct connection of the alignment ports on both sides using the same continuous alignment waveguide. If a direct connection is attempted between the alignment ports located on both sides of the main mode-changing waveguide array, the connecting waveguide needs to cross within the same layer as the main mode-changing waveguide. This same-layer crossing introduces additional crossover loss and may lead to optical crosstalk.

[0004] It is evident that existing technologies have drawbacks such as difficulty in reducing the number of fiber array channels and the risk of waveguide crosstalk on the same layer, which increases the risk of optical crosstalk. Utility Model Content

[0005] This invention provides a mode converter and chip packaging component, which solves the problem in the prior art that it is difficult to reduce the number of fiber array channels and that waveguide crosstalk on the same layer is likely to occur, thereby increasing the risk of optical crosstalk.

[0006] This invention provides a mode converter, including a glass substrate, a main mode conversion waveguide, and an alignment coupling waveguide, both of which are disposed within the glass substrate. The main mode conversion waveguide extends along a first direction, with its first end used to connect to the service fiber channel in an optical fiber array, and its second end used to connect to a photonic integrated chip.

[0007] At least a portion of the alignment-coupled waveguide is U-shaped. The first and second ends of the alignment-coupled waveguide are located on the side face of the glass substrate and are situated on opposite sides of the main mode conversion waveguide along a second direction, respectively, for connecting the alignment fiber channel in the fiber array. The second direction is perpendicular to the first direction and lies in the plane of the main mode conversion waveguide. The first end of the alignment-coupled waveguide is directly connected to the second end of the alignment-coupled waveguide.

[0008] At least a portion of the waveguide segment of the aligned coupled waveguide is in a different plane from the plane of the main mode conversion waveguide.

[0009] Optionally, the alignment-coupled waveguide includes a first coupling waveguide segment, a first transition waveguide segment, a U-shaped waveguide segment, a second transition waveguide segment, and a second coupling waveguide segment connected together in sequence. The end of the first coupling waveguide segment closest to the glass substrate side face serves as the first end of the alignment-coupled waveguide, and the end of the second coupling waveguide segment closest to the glass substrate side face serves as the second end of the alignment-coupled waveguide.

[0010] The first coupled waveguide segment and the first transition waveguide segment are located on one side of the main mode conversion waveguide along the second direction, and the second coupled waveguide segment and the second transition waveguide segment are located on the other side of the main mode conversion waveguide along the second direction.

[0011] The first and second coupled waveguide segments extend in the same direction as the main mode conversion waveguide, and the plane containing the first and second coupled waveguide segments and the main mode conversion waveguide is located in the same plane. The first transition waveguide segment, the U-shaped waveguide segment, and the second transition waveguide segment are located in different planes from the plane containing the main mode conversion waveguide.

[0012] Optionally, the U-shaped waveguide segment is located on one side or the other side of the main mode conversion waveguide along a third direction, wherein the third direction is perpendicular to the first direction and the second direction, respectively.

[0013] Optionally, the U-shaped waveguide segment includes a first circular arc waveguide segment and a second circular arc waveguide segment connected together.

[0014] The first end of the first circular arc waveguide segment is connected to the end of the first transition waveguide segment away from the first coupled waveguide segment, the second end of the first circular arc waveguide segment is connected to the first end of the second circular arc waveguide segment, and the second end of the second circular arc waveguide segment is connected to the end of the second transition waveguide segment away from the second coupled waveguide segment.

[0015] The central angles corresponding to the first and second circular arc waveguide segments are the same, and the bending radii of the first and second circular arc waveguide segments are the same.

[0016] Optionally, the central angles corresponding to the first and second circular arc waveguide segments are both 90°, and the bending radii of the first and second circular arc waveguide segments are bending radii R, where 300μm≤bending radiusR≤400μm.

[0017] Optionally, the U-shaped waveguide segment also includes a straight waveguide segment, and the second end of the first circular arc waveguide segment is connected to the first end of the second circular arc waveguide segment through the straight waveguide segment.

[0018] Optionally, along the second direction, the spacing between the first and second ends of the aligned coupling waveguide is a transverse center spacing D, which is an integer multiple of the fiber array channel pitch.

[0019] Optionally, the first and second ends of the aligned coupling waveguide are symmetrically arranged on both sides of the main mode conversion waveguide along the second direction.

[0020] Optionally, there are multiple main mode conversion waveguides, and the multiple main mode conversion waveguides are arranged in an array along the second direction.

[0021] The mode converter provided by this invention constructs a three-dimensional wiring structure by forming alignment-coupled waveguides on different planes within a glass substrate. The two ends of this alignment-coupled waveguide serve as ports connecting alignment fiber channels in an optical fiber array. Compared to the traditional method of having at least four alignment fiber ports, this significantly reduces the number of fiber ports, thereby lowering the number of channels, cost, and packaging complexity of the optical fiber array. Furthermore, since at least a portion of the waveguide segment of the alignment-coupled waveguide is on a different plane from the main mode-conversion waveguide, they are vertically offset in three-dimensional space, thus avoiding losses and crosstalk caused by their intersection in the same plane. Moreover, this structure is compatible with existing optical fiber arrays and silicon photonics chip edge-coupled packaging processes.

[0022] This invention also provides a chip packaging component, which employs the mode converter involved in the above embodiments and possible implementations, and further includes an optical fiber array and a photonic integrated chip.

[0023] The mode converter is connected to the alignment fiber channel of the fiber array through the first and second ends of the alignment coupling waveguide, and to the service fiber channel of the fiber array through one end of the main mode conversion waveguide. The other end of the main mode conversion waveguide is connected to the edge coupling port of the photonic integrated chip. This packaged component has a simple packaging structure, low cost, and is not prone to optical crosstalk. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural diagram of the pattern converter according to an embodiment of the present invention. Figure 1 ; Figure 2 This is a three-dimensional structural diagram of the pattern converter according to an embodiment of the present invention. Figure 2 ; Figure 3a This is a schematic diagram of the U-shaped waveguide segment in the mode converter of this utility model embodiment. Figure 1 ; Figure 3b This is a schematic diagram of the U-shaped waveguide segment in the mode converter of this utility model embodiment. Figure 2 ; Figure 4 This is a side view of the pattern converter according to an embodiment of the present invention; Figure 5 This is a side view of the chip packaging assembly according to an embodiment of the present invention; Figure 6 This is a top view of the chip packaging assembly according to an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures: 1. Mode converter; 10. Glass substrate; 101. Side end face; 11. Main mode converter waveguide; 12. Alignment coupling waveguide; 121. First end; 122. Second end; 123. First coupling waveguide segment; 124. First transition waveguide segment; 125. U-shaped waveguide segment; 1251. First circular arc waveguide segment; 1252. Second circular arc waveguide segment; 1253. Straight waveguide segment; 126. Second transition waveguide segment; 127. Second coupling waveguide segment; 2. Chip packaging assembly; 21. Fiber array; 211. First aligned fiber channel; 212. Service fiber channel; 213. Second aligned fiber channel; 22. Photonic integrated chip; 221. Edge coupling port; X, the first direction; Y, the second direction. Detailed Implementation

[0026] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0027] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use. They are only for the convenience of describing the utility model 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 the utility model.

[0029] The terms “first”, “second”, etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0030] In the description of this embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or an optical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.

[0031] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0032] This utility model provides a pattern converter 1, please refer to Figures 1-6 The system includes a glass substrate 10, a main mode conversion waveguide 11, and an alignment coupling waveguide 12, both of which are disposed within the glass substrate 10. The main mode conversion waveguide 11 extends along a first direction X (e.g., ...). Figure 1 As shown), the first end of the main mode conversion waveguide 11 is used to connect to the service fiber channel 212 in the fiber array 21 (as shown). Figure 6 As shown), the second end of the main mode conversion waveguide 11 is used to connect to the photonic integrated chip 22 (as shown). Figure 6 (As shown in the image). Here, the connection can be understood as an optical connection or optical coupling.

[0033] like Figure 1 and Figure 2As shown, the alignment coupling waveguide 12 is U-shaped. The first end 121 and the second end 122 of the alignment coupling waveguide 12 are located on the side face 101 of the glass substrate and are respectively located on both sides of the main mode conversion waveguide 11 along the second direction Y, for connecting the alignment fiber channel in the fiber array. The second direction Y is perpendicular to the first direction X and located in the plane of the main mode conversion waveguide 11. The first end of the alignment coupling waveguide is directly connected to the second end of the alignment coupling waveguide, or it can be understood that light can pass through the first end of the alignment coupling waveguide and directly reach its second end. In one embodiment, the alignment coupling waveguide itself is a continuous integral structure. The first direction X can be understood as the length direction of the main mode conversion waveguide 11, and the second direction Y can be understood as the width direction of the main mode conversion waveguide 11. At least a portion of the waveguide segment of the alignment coupling waveguide 12 is located in a different plane from the plane of the main mode conversion waveguide 11. The plane on which the main mode conversion waveguide 11 is located can be understood as the plane formed by the intersection of the central axis of the main mode conversion waveguide 11 and the width extension line of the main mode conversion waveguide 11, or it can be understood as the longitudinal section of the main mode conversion waveguide 11 along its width direction, which is parallel to the horizontal plane, or it can be understood as the plane on which the overall structure of the main mode conversion waveguide 11 is located.

[0034] As will be understood by those skilled in the art, a glass mode converter is a specific implementation of a mode-changing optical waveguide chip. It uses glass as the waveguide substrate and forms the main mode-changing waveguide within the glass substrate. The glass mode converter has the same basic function as existing planar mode-changing optical waveguide chips, both used for mode field matching between fiber arrays and photonic integrated chips.

[0035] The mode converter 1 provided by this invention constructs a three-dimensional wiring structure by forming the alignment coupling waveguide 12 on different planes within the glass substrate 10. The two ends of the alignment coupling waveguide 12 serve as ports for connecting alignment fiber channels in the fiber array. Compared to the traditional at least four alignment fiber ports, this significantly reduces the number of fiber ports, lowering the number of channels, cost, and packaging complexity of the fiber array. Furthermore, since at least a portion of the waveguide segment of the alignment coupling waveguide 12 is on a different plane from the main mode conversion waveguide 11, they are vertically offset in three-dimensional space, thus avoiding losses and crosstalk caused by their intersection in the same plane. Moreover, this structure is compatible with existing fiber arrays and silicon photonics chip edge-coupled packaging processes.

[0036] This invention, through the aforementioned structure—specifically, the staggered arrangement in the height direction—avoids physical intersections between the U-shaped waveguide segment 125 and the main mode conversion waveguide 11 on the same layer, and reduces the optical coupling between them. This ensures that the crosstalk between the alignment coupling waveguide 12 and the main mode conversion waveguide array meets design requirements, preferably less than -50 dB. Furthermore, this invention can construct a return-type monitoring optical path for active coupling alignment in a passive glass mode converter without increasing (or even decreasing) the alignment coupling waveguide loop. It achieves the connection of two alignment ports on the same fiber array side face through a continuous three-dimensional U-shaped waveguide, reducing additional fiber channels. Moreover, by utilizing the vertical space of the glass substrate, the alignment coupling waveguide 12 does not physically intersect with the main mode conversion waveguide 11 when crossing it, effectively reducing crossover loss and optical crosstalk.

[0037] The main mode conversion waveguide 11 extends from the side end face 101 of the glass substrate 10 to its opposite end face, and is used to convert between the mode field of the fiber array and the mode field of the edge coupler of the photonic integrated chip. The main mode conversion waveguide has a gradient structure, such as a gradient cross-section, a gradient refractive index distribution, a gradient multi-scan trajectory, or a gradient multi-core coupling structure. The specific structure can adopt existing technology, and this invention does not limit it. In addition, this invention does not limit the material of the glass substrate 10, such as fused silica, borosilicate glass, or other transparent glass. The side end face 101 and the opposite end face of the glass substrate 10 can be vertically polished, angled polished, or treated with anti-reflective coatings to meet different reflection and coupling requirements.

[0038] This invention does not limit the formation process of the aligned coupling waveguide 12. In one embodiment, it is formed using femtosecond laser direct writing. As those skilled in the art will understand, femtosecond laser direct writing is a processing method that uses an ultrashort pulse laser with a pulse width on the order of femtoseconds to scan point by point and line by line within or on the surface of a material according to a predetermined trajectory, thereby directly forming a waveguide, microchannel, microstructure, or refractive index modified region. In other alternative embodiments, an equivalent processing method capable of forming a continuous three-dimensional low-loss waveguide within a transparent substrate may also be used.

[0039] In one implementation, such as Figure 1As shown, there can be one or more main mode conversion waveguides 11, arranged in an array along the second direction Y. In a specific embodiment, the thickness of the glass substrate 10 can be 0.9–1.2 mm, the width can be 1.5–2 mm, and the length can be 2–4 mm. Those skilled in the art will understand that the above dimensions are merely examples and not fixed limitations on all embodiments. The width of the glass substrate 10 can be adjusted according to the number of main mode conversion waveguide channels, the fiber array channel pitch, the positions of the two alignment ports, and whether a lateral connecting section is provided in the U-shaped turning section.

[0040] In one implementation, please refer to Figure 1 The alignment-coupled waveguide 12 includes a first coupling waveguide segment 123, a first transition waveguide segment 124, a U-shaped waveguide segment 125, a second transition waveguide segment 126, and a second coupling waveguide segment 127 connected together in sequence. The end of the first coupling waveguide segment 123 closest to the glass substrate side face serves as the first end 121 of the alignment-coupled waveguide 12, and the end of the second coupling waveguide segment 127 closest to the glass substrate side face serves as the second end 122 of the alignment-coupled waveguide 12.

[0041] The first coupling waveguide segment 123 and the first transition waveguide segment 124 are located on one side of the main mode conversion waveguide 11 along the second direction Y, and the second coupling waveguide segment 127 and the second transition waveguide segment 126 are located on the other side of the main mode conversion waveguide 11 along the second direction Y.

[0042] The extension directions of the first coupling waveguide segment 123 and the second coupling waveguide segment 127 are consistent with the extension direction of the main mode conversion waveguide 11. Specifically, the first coupling waveguide segment 123 and the second coupling waveguide segment 127 are located in the same plane as the main mode conversion waveguide 11. Alternatively, this can be understood as the two ends of the aligned coupling waveguide 12 and the ports of the main mode conversion waveguide at their corresponding end faces being at the same height and on the same plane.

[0043] The first transition waveguide segment 124, the U-shaped waveguide segment 125, and the second transition waveguide segment 126 are located on different planes from the plane containing the main mode conversion waveguide 11. In one embodiment, the U-shaped waveguide segment is located on one side or the other side of the main mode conversion waveguide along a third direction, wherein the third direction is perpendicular to the first direction and the second direction, or can be understood as the normal direction of the plane containing the main mode conversion waveguide.

[0044] like Figure 1As shown, the first transition waveguide section 124, the U-shaped waveguide section 125, and the second transition waveguide section 126 are all located on the lower side of the main mode conversion waveguide 11. In other alternative embodiments, the first transition waveguide section 124, the U-shaped waveguide section 125, and the second transition waveguide section 126 are all located on the upper side of the main mode conversion waveguide 11. The term "upper side" or "lower side" can be understood as maintaining a certain vertical center-to-center distance from the main mode conversion waveguide 11. This vertical center-to-center distance is determined based on the waveguide mode field size, waveguide refractive index difference, operating wavelength, short-distance parallel length, and target crosstalk, and is typically on the order of tens of micrometers or larger, without a fixed numerical limit.

[0045] In one exemplary embodiment, the first end 121 and the second end 122 of the alignment coupling waveguide 12 are symmetrically arranged on both sides of the main mode conversion waveguide 11 along the second direction Y. In other alternative embodiments, the first end 121 and the second end 122 of the alignment coupling waveguide 12 can also be asymmetrically arranged. Asymmetrical arrangement can be understood as the first end 121 and the second end 122 of the alignment coupling waveguide 12 being unequal in lateral distance from the center of the main mode conversion waveguide 11. The port positions of the main mode conversion waveguide 11 on the fiber array side face correspond to the service fiber channels in the fiber array. If there are multiple main mode conversion waveguides 11, the center-to-center spacing between adjacent ports is preferably equal to the channel pitch p of the fiber array. The cladding diameter of a single-mode fiber is typically about 125 μm; therefore, 127 μm is a widely used fiber array pitch.

[0046] In one embodiment, along the second direction Y, the distance between the first end 121 and the second end 122 of the aligned coupling waveguide 12 is a lateral center-to-center distance D, which is an integer multiple of the fiber array channel pitch, i.e., D = Np, where N is a positive integer. For example, when p is 127 μm, the lateral center-to-center distance between the two aligned ports can be an integer multiple of 127 μm. In a further embodiment, the mode field size of the aligned coupling waveguide 12 near the port is preferably matched with the mode field of the single-mode fiber. Alternatively, a local mode conversion section can be provided before entering the U-shaped waveguide section 125 to convert the port-side mode field into a mode field suitable for low-loss bending transmission.

[0047] In a further implementation, such as Figure 1 and Figure 2As shown, the first transition waveguide segment 124 and the second transition waveguide segment 126 are gently sloping S-shaped structures. Alternatively, the first transition waveguide segment 124 can be understood as gradually rising or falling from the port height plane to the plane containing the U-shaped waveguide segment 125, such that the first transition waveguide segment 124 and the second transition waveguide segment 126 extend in the first direction X while undergoing vertical displacement, forming a smooth connection with the U-shaped waveguide segment 125. In other alternative embodiments, the first transition waveguide segment 124 and the second transition waveguide segment 126 can also be smooth L-shaped structures or oblique structures.

[0048] For further implementation methods, please refer to Figure 3a and Figure 3b and combined Figure 1 and Figure 2 Understandably, the U-shaped waveguide segment 125 includes a first circular arc waveguide segment 1251 and a second circular arc waveguide segment 1252 connected together.

[0049] The first end of the first arc waveguide segment 1251 is connected to the end of the first transition waveguide segment 124 away from the first coupling waveguide segment 123, the second end of the first arc waveguide segment 1251 is connected to the first end of the second arc waveguide segment 1252, and the second end of the second arc waveguide segment 1252 is connected to the end of the second transition waveguide segment 126 away from the second coupling waveguide segment 127.

[0050] The central angles corresponding to the first circular arc waveguide segment 1251 and the second circular arc waveguide segment 1252 are the same, and the bending radii of the first circular arc waveguide segment 1251 and the second circular arc waveguide segment 1252 are the same. This bending radius can also be understood as the planar radius of curvature of the U-shaped waveguide segment 125. In a specific embodiment, the central angles corresponding to the first and second circular arc waveguide segments are both 90°. Figure 3a As shown, both central angles A1 and A2 are 90°. In other embodiments, other angles may also be used. The bending radius of the first circular arc waveguide segment 1251 and the second circular arc waveguide segment 1252 is the bending radius R, where 300μm ≤ bending radius R ≤ 400μm.

[0051] In a further embodiment, when the number of channels in the main mode conversion waveguide 11 is large, the main waveguide array is wide, or the distance between the two alignment ports is large, such as Figure 3b As shown, the U-shaped waveguide segment 125 also includes a straight waveguide segment 1253, and the second end of the first circular arc waveguide segment 1251 is connected to the first end of the second circular arc waveguide segment 1252 through the straight waveguide segment 1253. The length of the straight waveguide segment 1253 is determined according to the width of the main waveguide array, the number of main waveguide channels, the fiber array pitch, and the positions of the two alignment ports.

[0052] In a further implementation, such as Figure 4As shown, the vertical distance between the plane containing the central axis of the main mode conversion waveguide 11 and the bottom surface of the glass substrate 10 is 750±20 μm. The plane containing the U-shaped waveguide section 125 and the plane containing the central axis of the main mode conversion waveguide 11 have a vertical center-to-center distance. This vertical center-to-center distance is determined according to the waveguide mode field size, refractive index difference, operating wavelength, short-distance parallel length and target crosstalk, and is usually on the order of tens of micrometers or larger. This utility model does not impose a fixed limit on its specific value.

[0053] Please see Figure 5 and Figure 6 This invention also provides a chip packaging component 2, which employs the mode converter 1 described in the above embodiments and possible implementations, and further includes an optical fiber array 21 and a photonic integrated chip 22. The mode converter 1 is connected to the first aligned optical fiber channel 211 and the second aligned optical fiber channel 213 of the optical fiber array 21 via the first end 121 and the second end 122 of the alignment coupling waveguide 12. The mode converter 1 is connected to the service optical fiber channel 212 of the optical fiber array 21 via one end of the main mode conversion waveguide 11. The other end of the mode converter 1 is connected to the edge coupling port 221 of the photonic integrated chip 22.

[0054] Please combine Figure 1 , Figure 5 and Figure 6 In the encapsulation process, the first alignment fiber channel 211 in the fiber array 21 corresponds to one end of the alignment coupling waveguide 12, and the second alignment fiber channel 213 corresponds to the other end of the alignment coupling waveguide 12. The monitoring light enters one end of the alignment coupling waveguide 12 from the first alignment fiber channel 211, passes sequentially through the first coupling waveguide segment 123, the first transition waveguide segment 124, the U-shaped waveguide segment 125, the second transition waveguide segment 126, and the second coupling waveguide segment 127, and finally couples from the other end of the alignment coupling waveguide 12 to the second alignment fiber channel 213. In other alternative encapsulation processes, the monitoring light can enter the other end of the alignment coupling waveguide 12 from the second alignment fiber channel 213 and finally exit from one end of the alignment coupling waveguide 12.

[0055] The packaging equipment adjusts the lateral, vertical, axial spacing, and angle of the fiber array relative to the glass modulator to maximize the output power or meet a preset threshold, and then cures the adhesive material. This packaging assembly has a simple structure, low cost, and is less prone to optical crosstalk. Those skilled in the art will understand that the glass modulator and the photonic integrated chip can be packaged using existing active or passive alignment techniques; this invention does not specifically limit this aspect.

[0056] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A pattern converter, characterized in that, include: The system comprises a glass substrate, a main mode conversion waveguide, and an alignment coupling waveguide, wherein the main mode conversion waveguide and the alignment coupling waveguide are both disposed within the glass substrate; the main mode conversion waveguide extends along a first direction, and a first end of the main mode conversion waveguide is used to connect to the service fiber channel in the fiber array, and a second end of the main mode conversion waveguide is used to connect to the photonic integrated chip. At least a portion of the alignment-coupled waveguide segment is U-shaped. The first and second ends of the alignment-coupled waveguide are located on the side end face of the glass substrate and are respectively located on both sides of the main mode conversion waveguide along the second direction, for connecting the alignment fiber channel in the fiber array. The second direction is perpendicular to the first direction and is located in the plane of the main mode conversion waveguide. The first end of the alignment-coupled waveguide is directly connected to the second end of the alignment-coupled waveguide. At least a portion of the waveguide segment of the aligned coupling waveguide is located in a different plane from the plane of the main mode conversion waveguide.

2. The pattern converter according to claim 1, characterized in that, The aligned coupling waveguide includes a first coupling waveguide segment, a first transition waveguide segment, a U-shaped waveguide segment, a second transition waveguide segment, and a second coupling waveguide segment connected together in sequence; wherein, the end of the first coupling waveguide segment closest to the glass substrate side face serves as the first end of the aligned coupling waveguide, and the end of the second coupling waveguide segment closest to the glass substrate side face serves as the second end of the aligned coupling waveguide. The first coupling waveguide segment and the first transition waveguide segment are located on one side of the main mode conversion waveguide along the second direction, and the second coupling waveguide segment and the second transition waveguide segment are located on the other side of the main mode conversion waveguide along the second direction. The first coupled waveguide segment and the second coupled waveguide segment extend in the same direction as the main mode conversion waveguide. The first coupled waveguide segment and the second coupled waveguide segment are located in the same plane as the main mode conversion waveguide. The first transition waveguide segment, the U-shaped waveguide segment, and the second transition waveguide segment are located in different planes from the plane of the main mode conversion waveguide.

3. The pattern converter according to claim 2, characterized in that, The U-shaped waveguide segment is located on one side or the other side of the main mode conversion waveguide along a third direction, wherein the third direction is perpendicular to the first direction and the second direction, respectively.

4. The pattern converter according to claim 2, characterized in that, The U-shaped waveguide segment includes a first circular arc waveguide segment and a second circular arc waveguide segment connected together. The first end of the first arc waveguide segment is connected to the end of the first transition waveguide segment away from the first coupling waveguide segment, the second end of the first arc waveguide segment is connected to the first end of the second arc waveguide segment, and the second end of the second arc waveguide segment is connected to the end of the second transition waveguide segment away from the second coupling waveguide segment. The first and second circular arc waveguide segments have the same central angle and the same bending radius.

5. The pattern converter according to claim 4, characterized in that, The central angles corresponding to the first and second circular arc waveguide segments are both 90°, and the bending radii of the first and second circular arc waveguide segments are bending radii R, where 300μm≤bending radii R≤400μm.

6. The pattern converter according to claim 4, characterized in that, The U-shaped waveguide segment also includes a straight waveguide segment, and the second end of the first arc waveguide segment is connected to the first end of the second arc waveguide segment through the straight waveguide segment.

7. The pattern converter according to claim 1, characterized in that, Along the second direction, the distance between the first end and the second end of the aligned coupling waveguide is a transverse center spacing D, which is an integer multiple of the fiber array channel pitch.

8. The pattern converter according to claim 1, characterized in that, The first and second ends of the aligned coupling waveguide are symmetrically arranged on both sides of the main mode conversion waveguide along the second direction.

9. The pattern converter according to claim 1, characterized in that, There are multiple main mode conversion waveguides, and the multiple main mode conversion waveguides are arranged in an array along the second direction.

10. A chip packaging assembly, characterized in that, The mode converter according to any one of claims 1 to 9 further includes an optical fiber array and a photonic integrated chip; The mode converter is connected to the alignment fiber channel of the fiber array through the first and second ends of the alignment coupling waveguide. The mode converter is connected to the service fiber channel of the fiber array through one end of the main mode conversion waveguide. The mode converter is connected to the edge coupling port of the photonic integrated chip through the other end of the main mode conversion waveguide.

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