CN114114530B - Transition waveguide structure, optical waveguide structure and optical coupling structure - Google Patents
Transition waveguide structure, optical waveguide structure and optical coupling structure Download PDFInfo
- Publication number
- CN114114530B CN114114530B CN202111181872.9A CN202111181872A CN114114530B CN 114114530 B CN114114530 B CN 114114530B CN 202111181872 A CN202111181872 A CN 202111181872A CN 114114530 B CN114114530 B CN 114114530B
- Authority
- CN
- China
- Prior art keywords
- face
- waveguide structure
- mode
- optical
- spot
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
- G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
- G02B6/12002—Three-dimensional structures
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
- G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
- G02B6/122—Basic optical elements, e.g. light-guiding paths
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
- G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
- G02B2006/12083—Constructional arrangements
- G02B2006/12085—Integrated
Abstract
The embodiment of the application provides a transition waveguide structure, optical waveguide structure and optical coupling structure, the transition waveguide structure includes: a first end face and a second end face which are parallel to each other, and a first bottom face which is perpendicular to the first end face and the second end face; the area of the first end face is smaller than that of the second end face; the first end face is used for receiving/outputting optical signals, and the corresponding second end face is used for outputting/receiving optical signals; the first through holes are distributed in an array, and the axial direction of each first through hole is perpendicular to the first bottom surface; the aperture of the first through hole increases in a direction from the first end face to the second end face. According to the transition waveguide structure, the first through holes distributed in the array are arranged, and the first through holes are increased in diameter along the direction from the first end face to the second end face, so that gradual change of the effective refractive index of the transition waveguide structure is realized, and loss in the optical signal transmission process is reduced.
Description
Technical Field
The embodiment of the application relates to the technical field of optical communication, in particular to a transition waveguide structure, an optical waveguide structure and an optical coupling structure.
Background
When the silicon material is applied to the field of photoelectric devices, the silicon material has obvious advantages in the manufacturing process and the manufacturing cost. However, because of the large difference in refractive index between silica-based optical waveguides and silica fibers, reflection and mode field mismatch are unavoidable.
In recent years, in order to improve coupling efficiency, in designing an optoelectronic device, more specifically, in designing a silicon optical chip, a transition structure between a waveguide and an optical fiber constitutes a hot spot for research.
Disclosure of Invention
In view of this, embodiments of the present application provide a transition waveguide structure, an optical waveguide structure, and an optical coupling structure to solve at least one technical problem existing in the prior art.
In order to achieve the above purpose, the technical scheme of the application is realized as follows:
in a first aspect, embodiments of the present application provide a transition waveguide structure, including: a first end face and a second end face which are parallel to each other, and a first bottom face which is perpendicular to the first end face and the second end face; the area of the first end face is smaller than that of the second end face; the first end face is used for receiving/outputting optical signals, and the corresponding second end face is used for outputting/receiving optical signals;
The first through holes are distributed in an array, and the axial direction of each first through hole is perpendicular to the first bottom surface;
the aperture of the first through hole increases in a direction from the first end face to the second end face.
According to one embodiment of the present application, the aperture of each of the first through holes decreases in a direction pointing toward the first bottom surface.
According to one embodiment of the present application, the first through hole is mirror symmetrical along a central axis of the transition waveguide structure, and an aperture of the first through hole increases in a direction away from the central axis.
According to one embodiment of the present application, each of the first through holes is formed by stacking a plurality of repeating units in the axial direction.
According to one embodiment of the present application, the shape of the repeating unit includes a cylinder, a truncated cone, a cuboid, a truncated pyramid, or a regular polyhedron.
According to one embodiment of the present application, the distances between the axes of any adjacent two of the first through holes are equal.
In a second aspect, embodiments of the present application provide an optical waveguide structure, including: a small-mode-spot waveguide structure, a large-mode-spot waveguide structure, and a transition waveguide structure as described in the above technical solutions; the transition waveguide structure is arranged between the small-mode-spot waveguide structure and the large-mode-spot waveguide structure.
According to one embodiment of the present application, the large-mode-spot waveguide structure includes: a third end face and a fourth end face parallel to each other; the third end face and the fourth end face are equal in size;
the large-mode-spot waveguide structure is provided with second through holes distributed in an array, and the axial direction of each second through hole is parallel to the third end face;
the second end face and the third end face are equal in size.
According to one embodiment of the present application, the small-mode-spot waveguide structure includes: a fifth end face and a sixth end face parallel to each other; the fifth end face and the sixth end face are equal in size;
the sixth end face is equal in size to the first end face.
In a third aspect, embodiments of the present application provide an optical coupling structure, including: a substrate, a silicon waveguide, an optical fiber, and an optical waveguide structure as described in the above technical scheme;
the optical waveguide structure is arranged above the substrate;
the silicon waveguide is arranged on one side of the small-mode-spot waveguide structure, and the optical fiber is arranged on one side of the large-mode-spot waveguide structure.
According to one embodiment of the present application, the refractive index of the small-mode-spot waveguide structure is the same as the refractive index of the silicon waveguide; the refractive index of the large-mode-spot waveguide structure is the same as that of the optical fiber.
The embodiment of the application provides a transition waveguide structure, an optical waveguide structure and an optical coupling structure, wherein the transition waveguide structure comprises: a first end face and a second end face which are parallel to each other, and a first bottom face which is perpendicular to the first end face and the second end face; the area of the first end face is smaller than that of the second end face; the first end face is used for receiving/outputting optical signals, and the corresponding second end face is used for outputting/receiving optical signals; the first through holes are distributed in an array, and the axial direction of each first through hole is perpendicular to the first bottom surface; the aperture of the first through hole increases in a direction from the first end face to the second end face. According to the transition waveguide structure, the first through holes distributed in the array are arranged, and the first through holes are formed along the direction from the first end face to the second end face, the aperture of the first through holes is increased, so that gradual change of the effective refractive index of the transition waveguide structure is realized, end face reflection loss and mode field conversion loss of the transition waveguide structure in the optical signal transmission process are reduced, and optical coupling efficiency is improved.
Drawings
FIG. 1 is a schematic three-dimensional structure of a transition waveguide structure;
FIG. 2 is a top view of a transition waveguide structure;
FIG. 3 is a cross-sectional view of the transition waveguide structure taken along AA' in FIG. 2;
FIGS. 4 and 5 are schematic structural views of a first repeating unit of a transition waveguide structure;
FIG. 6 is a partial top view of a transition waveguide structure;
FIG. 7 is a schematic three-dimensional structure of an optical waveguide structure;
FIG. 8 is a top view of an optical waveguide structure;
FIG. 9 is a cross-sectional view of the optical waveguide structure taken along BB' in FIG. 8;
FIG. 10 is a simplified top view of an optical waveguide structure;
FIG. 11 is a partial top view of a large mode spot waveguide structure;
FIG. 12 is a simplified top view of an optical coupling structure;
the drawings include: a 10-transition waveguide structure; 11-a first end face; 12-a second end face; 13-a first bottom surface; 20-large mode spot waveguide structure; 21-a third end face; 22-a fourth end face; 23-a second bottom surface; 30-a small-mode-spot waveguide structure; 31-a fifth end face; 32-a sixth end face; 33-a third bottom surface; 40-a first through hole; 41. 41' -a first repeat unit; 42-a first base unit; 50-a second through hole; 51-a second repeating unit; 52-a second base unit; 60-optical fiber; a 70-silicon waveguide; 80-a substrate; CDFE is the symmetry plane of the transition waveguide structure; GH is the central axis of the transition waveguide structure.
Detailed Description
The following description of the embodiments of the present application will be made clearly and fully with reference to the embodiments of the present application and the accompanying drawings, and it is apparent that the described embodiments are only some, but not all, embodiments of the present application. All other embodiments, based on the embodiments herein, which would be apparent to one of ordinary skill in the art without undue burden are within the scope of the present application.
In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application may be practiced without one or more of these details. In other instances, well-known features have not been described in detail so as not to obscure the application; that is, not all features of an actual implementation are described in detail herein, and well-known functions and constructions are not described in detail.
In the drawings, the size of layers, regions, elements and their relative sizes may be exaggerated for clarity. Like numbers refer to like elements throughout.
It will be understood that when an element or layer is referred to as being "on" … …, "" adjacent to "… …," "connected to" or "coupled to" another element or layer, it can be directly on, adjacent to, connected to or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on" … …, "" directly adjacent to "… …," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present application. When a second element, component, region, layer or section is discussed, it does not necessarily mean that the first element, component, region, layer or section is present in the present application.
Spatially relative terms, such as "under … …," "under … …," "below," "under … …," "above … …," "above," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements or features described as "under" or "beneath" other elements would then be oriented "on" the other elements or features. Thus, the exemplary terms "under … …" and "under … …" may include both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.
For a thorough understanding of the present application, detailed steps and detailed structures will be presented in the following description in order to explain the technical aspects of the present application. Preferred embodiments of the present application are described in detail below, however, the present application may have other implementations in addition to these detailed descriptions.
The embodiment of the application provides a transition waveguide structure. Referring to fig. 1, fig. 1 is a schematic three-dimensional structure of a transition waveguide structure. As shown in fig. 1, the transition waveguide structure 10 includes a first end face 11 and a second end face 12 that are parallel to each other, and a first bottom face 13 that is perpendicular to the first end face 11 and the second end face 12; the transition waveguide structure 10 further comprises first through holes 40 distributed in an array, the axial direction of each first through hole 40 being perpendicular to the first bottom surface 13.
In some embodiments of the present application, the first end face has an area that is smaller than an area of the second end face. The first end face may be rectangular, and the second end face may also be rectangular.
In some embodiments of the present application, the first end face is configured to receive/output an optical signal, and the corresponding second end face is configured to output/receive an optical signal. Specifically, the first end face may be used to receive an optical signal, the second end face may be used to output an optical signal, the optical signal may be input into the transition waveguide structure by the first end face, and the optical signal is output from the transition waveguide structure by the second end face; alternatively, the second end face may be used to receive an optical signal, the first end face may be used to output an optical signal, and the optical signal may be input to the transition waveguide structure by the second end face, at which point the optical signal is output from the transition waveguide structure by the first end face. That is, the propagation direction of the optical signal in the transition waveguide structure may be either in the direction from the first end face to the second end face or in the direction from the second end face to the first end face.
Referring to fig. 2, fig. 2 is a top view of a transition waveguide structure. As shown in fig. 2, the first through holes 40 are present in an array distribution within the transition waveguide structure 10. The direction parallel to the first end face and the second end face is referred to as a row direction, i.e., an X direction, the direction perpendicular to the first end face and the second end face is referred to as a column direction, or the direction parallel to the propagation direction of the optical signal is referred to as a column direction, i.e., a Z direction. Specifically, the shape of the transition waveguide structure may be a quadrangular frustum of a pyramid, and the transition waveguide structure may be an isosceles trapezoid in a top view, a direction parallel to the upper and lower bottoms of the isosceles trapezoids may be referred to as a row direction, a direction parallel to the height of the isosceles trapezoids may be referred to as a column direction, and a plurality of rows and columns of first through holes may be distributed in the transition waveguide structure.
In some embodiments of the present application, the aperture of the first through hole increases in a direction from the first end face to the second end face. Specifically, the effective refractive index of the transition waveguide structure gradually decreases in the direction from the first end face to the second end face. In one embodiment of the present application, the effective refractive index of the transition waveguide structure decreases non-linearly in the direction from the first end face to the second end face.
According to the transition waveguide structure, through the arrangement of the first through holes distributed in the array, the axial direction of each first through hole is perpendicular to the first bottom surface, the aperture of each first through hole is along the direction of the first end surface to the second end surface, namely, the Z direction, the aperture of each first through hole is increased, so that gradual change of the effective refractive index of the transition waveguide structure is realized, the end surface reflection loss and the mode field conversion loss of the transition waveguide structure in the optical signal transmission process are reduced, and the optical coupling efficiency is improved.
In some embodiments of the present application, the aperture of each of the first through holes decreases in a direction pointing toward the first bottom surface.
Referring to fig. 3, fig. 3 is a cross-sectional view of the transition waveguide structure taken along AA' in fig. 2. Fig. 3 shows a cross-sectional structure of the first through hole 40 in the Z direction, the axial direction of the first through hole 40 being perpendicular to the first bottom surface 13, in other words, the axial direction of the first through hole 40 being parallel to the first end surface 11 and the second end surface 12; the aperture of each first through hole 40 decreases in a direction directed toward the first bottom surface 13. Specifically, each of the first through holes is tapered in a sectional view, that is, the smaller the distance of the first through hole from the first bottom surface along the axial direction of the first through hole, the smaller the aperture of the first through hole.
According to the transition waveguide structure, the first through holes distributed in the array mode are arranged, and the aperture of each first through hole is reduced along the direction pointing to the first bottom face. The optical paths of the optical signals of different paths are approximately equal in the optical signals entering the transition waveguide structure, so that the divergence angle is reduced, and the near collimation function is realized.
In some embodiments of the present application, the first through hole is mirror symmetrical along a central axis of the transition waveguide structure, and an aperture of the first through hole increases in a direction away from the central axis.
Referring to fig. 1, the first end face 11 may be rectangular, and an intersection point of diagonal lines of the first end face 11 is denoted as G; the second end face 12 may also be rectangular, and the intersection of the diagonal lines of the second end face 12 is denoted as H. The GH connecting line is the central axis of the transition waveguide structure. The first through holes are in mirror symmetry along the central axis of the transition waveguide structure, and the farther the first through holes are from the central axis, the larger the aperture of the first through holes are.
Still referring to fig. 1, the symmetry plane CDFE of the transition waveguide structure is a plane passing through the above-mentioned central axis GH and perpendicular to the first end face 11 and the second end face 12, and the symmetry plane CDFE of the transition waveguide structure is perpendicular to the first bottom face 13. Wherein C and E are respectively midpoints of two side lengths of the first end face, which are parallel to each other, and D and F are respectively midpoints of two side lengths of the second end face, which are parallel to each other. In other words, the symmetry plane of the transition waveguide structure is parallel to the propagation direction of the optical signal, i.e. the symmetry plane of the transition waveguide structure is parallel to the Z-direction. The transition waveguide structure is in mirror symmetry with respect to the symmetry plane, and the first through hole provided in the transition waveguide structure is also in mirror symmetry with respect to the symmetry plane.
Still referring to fig. 2, fig. 2 shows a top view of the transition waveguide structure. Specifically, the transition waveguide structure may have a rectangular parallelepiped shape, and may have an isosceles trapezoid shape in plan view, and in this case, C, G, E coincides with one point in plan view, and D, H, F coincides with one point in plan view. The CD connection line shown in fig. 2 is the symmetry axis of the trapezoid, that is, the orthographic projection of the transition waveguide structure on the first bottom surface is mirror symmetrical with respect to the symmetry axis. And, for the first through holes of the same row, that is, the first through holes distributed in the X direction, the farther the first through holes are from the symmetry axis, the larger the aperture of the first through holes. In other words, the first through holes distributed along the X direction have their diameters decreased and then increased. Specifically, the refractive index of the transition waveguide structure in the X direction is increased and then reduced, wherein the refractive index of the transition waveguide structure at the position of the symmetry axis is slightly larger than the refractive index of the transition waveguide structure at the positions of two sides of the transition waveguide structure.
If the number of first through holes distributed in the X direction is an odd number, the aperture of one first through hole located on the symmetry axis is the smallest; if the number of first through holes distributed in the X direction is even, the aperture of the two first through holes closest to the symmetry axis is smallest. Fig. 2 shows a case where the number of first through holes distributed in the X direction is even. According to the transition waveguide structure, the first through holes distributed in the array mode are arranged, and the aperture of each first through hole is reduced along the direction pointing to the first bottom face; the first through holes are in mirror symmetry along the central axis of the transition waveguide structure, and the aperture of the first through holes increases along the direction away from the central axis. The optical paths of the optical signals of different paths are approximately equal in the optical signals entering the transition waveguide structure, so that the divergence angle is reduced, and the near collimation function is realized. And the refractive index of the transition waveguide structure at the two side positions in the X direction is slightly smaller than that of the central axis position in the X direction, so that the reflection loss can be effectively reduced.
Still referring to fig. 1, the shape of the transition waveguide structure may be a quadrangular frustum, and four side edges of the quadrangular frustum are lengthened and then intersect at a point, and a coordinate system is established by taking the intersection point as an origin O. Alternatively, the rectangular parallelepiped can be regarded as a portion between the bottom surface of the rectangular pyramid and a cross section parallel to the bottom surface, and in this case, the vertex of the rectangular pyramid is the origin O of the coordinate system. The directions parallel to the two side lengths perpendicular to the first end face are set as the X direction and the Y direction of the coordinate system, respectively, the directions perpendicular to the first end face and the second end face are set as the Z direction of the coordinate system, or the directions parallel to the propagation direction of the optical signal are set as the Z direction of the coordinate system.
The X-direction and Z-direction shown in fig. 1 are the same as the X-direction and Z-direction shown in fig. 2. The origin O of the coordinate system shown in fig. 1 is also the intersection point of the extension lines of the divergence angle when the transition waveguide structure provided in the embodiment of the present application is not adopted. The following formula 1 is a distribution function of refractive index within the transition waveguide structure:
wherein n represents the refractive index of a point in the coordinate system located at (x, y, z) in the transition waveguide structure, n SiO2 Represents the refractive index of silicon dioxide, n Si The refractive index of silicon is represented by x, y and Z, the coordinate position of a certain point in the transition waveguide structure is represented by x, y and Z, the length of the transition waveguide structure in the Z direction is represented by L, the minimum distance from the origin O of the coordinate system to the first end face is represented by L, namely, the distance from the origin O of the coordinate system to the first end face in the Z direction is represented by L, and a, b, c, A, m and n' are adjustable parameters.
In one embodiment of the present application, a may be 0.001, b may be 0.0001, c may be 2, and a may be 0.01. Here, the values of a and b are selected to be slightly larger than 0, so that scattering caused by roughness of the boundary can be reduced.
In one embodiment of the present application, L may be 50 μm.
From the analysis of equation 1, it is known that, in the case where the parameters a, b, c, A, m, n', L and L are unchanged, the coordinate position in the Z direction is constant for each first through hole, the larger the coordinate position values in the X direction and the Y direction are, the smaller the refractive index of the point is, and thus the larger the corresponding aperture is. Thus, the first through hole appears as a tapered hole topography in the cross-sectional view shown in fig. 3.
Specifically, in the transition waveguide structure, the refractive index of the transition waveguide structure gradually decreases in the direction from the first end face to the second end face, i.e., in the Z direction shown in fig. 1; along the direction of the section line, the refractive index of the transition waveguide structure increases and then decreases. Wherein the cross-sectional direction refers to any direction parallel to the first bottom surface and perpendicular to the Z direction shown in fig. 1, that is, the X direction shown in fig. 1. It will be appreciated that the aperture of the first via decreases and then increases in the X direction, and therefore the refractive index of the transition waveguide structure increases and then decreases in the X direction.
Specifically, the magnitude relation between the effective refractive index and the aperture of a certain point in the transition waveguide structure can be obtained by a numerical simulation mode. Still referring to fig. 2, the transition waveguide structure is divided into several cubes of equal size, as indicated by the dashed lines in fig. 2, which are referred to as first basic units 42 in connection with fig. 4, one first repeating unit 41 being present in each first basic unit 42. In other words, in the transition waveguide structure, several first basic units are stacked in the column direction (i.e., Z direction) and the row direction (i.e., X direction), respectively, to form the transition waveguide structure. And, a plurality of the first repeating units are stacked in a direction perpendicular to the first bottom surface (i.e., Y direction) to form the first through hole.
Here, the magnitude relation between the effective refractive index and the aperture at a certain point in the transition waveguide structure can be obtained by means of numerical simulation, and the refractive index value corresponding to the side length of the aperture increasing from 0 to the first basic unit is calculated and obtained in a step length smaller than 0.1 nm. Considering that the calculation amount is large, a parameterized modeling method can be used, firstly, a rectangular waveguide is established by using a first basic unit array, the relation between the effective refractive index and the aperture size is calculated by a numerical simulation mode, and the relation is stored in an array mode, for example, each aperture value corresponds to one refractive index value; then, the spatial distribution of the effective refractive index is calculated through a formula and stored in an array mode, for example, each coordinate position corresponds to one refractive index value; finally, discretizing the transition waveguide structure, namely dividing the transition waveguide structure into a plurality of first basic units with the same size, and selecting the aperture size in each first basic unit through the effective refractive index corresponding to the coordinate position of each first basic unit.
According to the transition waveguide structure, the first through holes distributed in the array mode are arranged, and the aperture of each first through hole is reduced along the direction pointing to the first bottom face; the first through holes are in mirror symmetry along the central axis of the transition waveguide structure, and the aperture of the first through holes increases along the direction away from the central axis. The effective refractive index distribution in the transition waveguide structure satisfies the principle of identical optical path difference, so as to ensure that the equiphase surface of the optical signal output after passing through the transition waveguide structure is still a plane. Here, the design of the transition waveguide structure enables refractive index matching to reduce reflection loss, thereby improving optical coupling efficiency.
In some embodiments of the present application, each of the first through holes is stacked with a plurality of first repeating units in an axial direction. Specifically, each of the first through holes is formed by stacking a plurality of first repeating units in the Y direction shown in fig. 1.
Referring to fig. 4 and 5, fig. 4 and 5 are schematic structural views of a first repeating unit of the transition waveguide structure. As shown in fig. 4 and 5, the first basic unit 42 is perforated to obtain a first repeating unit 41. The first repeating unit 41 shown in fig. 4 has a truncated cone shape, and the first repeating unit 41' shown in fig. 5 has a quadrangular prism shape. A number of first basic cells are stacked in a column direction (i.e., Z direction) and a row direction (i.e., X direction), respectively, to form a transition waveguide structure. And, a plurality of the first repeating units are stacked in a direction perpendicular to the first bottom surface (i.e., Y direction) to form the first through hole.
In some embodiments of the present application, the side length of the first basic unit needs to satisfy the condition of sub-wavelength. For example, in one specific embodiment, the first basic unit has a side length <23nm.
In some embodiments of the present application, the shape of the first repeating unit may include a cylinder, a truncated cone, a cuboid, a truncated pyramid, or a regular polyhedron.
In some embodiments of the present application, the distances between the axes of any adjacent two of the first through holes are equal.
Referring to fig. 6, fig. 6 is a partial top view of a transition waveguide structure. Fig. 6 shows four rows and four columns of sixteen first basic units in total, one first repeating unit 41 being provided in each first basic unit 42, the first repeating unit being part of a first through hole. The dashed lines shown in fig. 6 are diagonal lines of each first basic unit 42, and the intersection points of the dashed lines are the geometric centers of each first basic unit in the plan view, and the intersection points of the dashed lines are the geometric centers of each first repeating unit in the plan view. In other words, the geometric center of each first basic unit and each first repeating unit coincides in plan view. It will be appreciated that the dimensions of each first basic unit are the same, and that the distance between the geometric centers of orthographic projections of any two adjacent first through holes on said first bottom surface is equal, i.e. the distance is the side length of the first basic unit. From the above analysis, it is known that the number of the first through holes per unit volume is constant, that is, the distribution density of the first through holes is uniform, in the transition waveguide structure. Each first through hole is composed of a plurality of first repeating units in the first basic units which are arranged along the Y direction, the geometric center of each first repeating unit in the top view is coincident with each first through hole, the axis of each first through hole is composed of the axis of each first repeating unit, and the orthographic projection of the axis of each first repeating unit on the first bottom surface is coincident with the geometric center.
The transition waveguide structure provided by the embodiment of the application realizes the control of the effective refractive index through the periodic structure of the sub-wavelength, namely, the first repeating units which are arranged periodically. Specifically, the transition waveguide structure provided by the embodiment of the application realizes the change of the effective refractive index in different directions through the first through hole, for example, the conical hole.
The embodiment of the application also provides an optical waveguide structure. Referring to fig. 7, fig. 7 is a schematic three-dimensional structure of an optical waveguide structure. As shown in fig. 7, the optical waveguide structure includes a small-mode-spot waveguide structure 30, a large-mode-spot waveguide structure 20, and a transition waveguide structure 10; the transition waveguide structure 10 is disposed between the small-mode-spot waveguide structure 30 and the large-mode-spot waveguide structure 20. In the optical waveguide structure shown in fig. 7, the propagation of an optical signal may sequentially pass through the small-mode-spot waveguide structure 30, the transition waveguide structure 10, and the large-mode-spot waveguide structure 20, and at this time, the transition waveguide structure 10 is configured to receive the optical signal output from the small-mode-spot waveguide structure 30 and transmit the optical signal to the large-mode-spot waveguide structure 20. Of course, in the optical waveguide structure shown in fig. 7, the propagation of the optical signal may sequentially pass through the large-mode-spot waveguide structure 20, the transition waveguide structure 10, and the small-mode-spot waveguide structure 30, and at this time, the transition waveguide structure 10 is configured to receive the optical signal output from the large-mode-spot waveguide structure 20 and transmit the optical signal to the small-mode-spot waveguide structure 30. That is, the propagation direction of the optical signal in the optical waveguide structure may be bidirectional, and the optical signal may be incident from the small-mode-spot waveguide structure, after passing through the transition waveguide structure, and finally emitted from the large-mode-spot waveguide structure, or may be incident from the large-mode-spot waveguide structure, after passing through the transition waveguide structure, and finally emitted from the small-mode-spot waveguide structure.
With continued reference to fig. 7, the large-mode-spot waveguide structure 20 includes a third end face 21 and a fourth end face 22 that are parallel to each other, and a second bottom face 23 that is perpendicular to the third end face 21 and the fourth end face 22; the third end face 21 and the fourth end face 22 are equal in size; the large-mode-spot waveguide structure 20 further includes second through holes 50 distributed in an array, and an axial direction of each second through hole 50 is perpendicular to the second bottom surface 23.
Here, the large-mode-spot waveguide structure is connected to the transition waveguide structure, and at this time, the second end face and the third end face are equal in size. Specifically, the second end face may be rectangular, the third end face may be rectangular, the lengths and widths of the second end face and the third end face are the same, and the areas of the second end face and the third end face are equal.
Still referring to fig. 7, the small-mode-spot waveguide structure 30 includes a fifth end face 31 and a sixth end face 32 that are parallel to each other, and a third bottom face 33 that is perpendicular to the fifth end face 31 and the sixth end face 32; the fifth end face 31 is equal in size to the sixth end face 32.
Here, the small-mode spot waveguide structure is connected to the transition waveguide structure, and at this time, the sixth end face is equal in size to the first end face. Specifically, the sixth end face may be rectangular, the first end face may be rectangular, the lengths and widths of the sixth end face and the first end face are the same, and the areas of the sixth end face and the first end face are equal. It is understood that the third bottom surface, the first bottom surface and the second bottom surface are located on the same plane.
Referring to fig. 8, fig. 8 is a top view of an optical waveguide structure. As shown in fig. 8, the second through holes 50 are present in an array distribution within the large-mode-spot waveguide structure 20. The direction parallel to the third end face and the fourth end face is referred to as a row direction, i.e., an X direction, the direction perpendicular to the third end face and the fourth end face is referred to as a column direction, or the direction parallel to the propagation direction of the optical signal is referred to as a column direction, i.e., a Z direction. And a plurality of rows and columns of second through holes are distributed in the large-mode-spot waveguide structure.
In some embodiments of the present application, the dimensions of the second through-holes distributed within the large-mode-spot waveguide structure are the same. Specifically, the apertures of the second through holes are the same, and the depths of the second through holes in the axial direction thereof are the same.
Referring to fig. 9, fig. 9 is a cross-sectional view of the optical waveguide structure taken along BB' in fig. 8. Fig. 9 shows a cross-sectional structure of the first through hole 40 and the second through hole 50 in the Z direction, the axial direction of the second through hole 50 being perpendicular to the second bottom surface 23, in other words, the axial direction of the second through hole 50 being parallel to the third end surface 21 and the fourth end surface 22; the aperture of each second through hole 50 remains unchanged in the direction toward the second bottom surface 23. Specifically, each of the second through holes may be a cylindrical through hole, which appears rectangular in the cross-sectional view shown in fig. 9.
Referring to fig. 10, fig. 10 is a simplified top view of an optical waveguide structure. As shown in fig. 10, the orthographic projections of the small-mode-spot waveguide structure 30, the transition waveguide structure 10, and the large-mode-spot waveguide structure 20 have a third shape, a first shape, and a second shape, respectively, wherein the third shape and the second shape may be rectangular or square, and the intersections of diagonal lines of the third shape, the first shape, and the second shape are located on the same straight line. In other words, the third shape, the first shape, and the second shape are all axisymmetric patterns, and the symmetry axes of the third shape, the first shape, and the second shape are located on the same straight line. The straight line where the intersection point of the diagonal lines is located is the symmetry axis.
In some embodiments of the present application, the distances between the axes of any adjacent two of the second through holes are equal.
Referring to fig. 11, fig. 11 is a partial top view of a large mode spot waveguide structure. Fig. 11 shows three rows and three columns of a total of nine second basic units, one second repeating unit 51 being provided in each second basic unit 52, where the second repeating unit is part of a second through hole. Here, the second basic units 52 may be cubes, and the dotted line shown in fig. 11 is a diagonal line of each second basic unit 52, and the intersection point of the dotted line diagonal lines is the geometric center of each second basic unit in the top view, and at the same time, the intersection point of the dotted line diagonal lines is the geometric center of each second repeating unit in the top view. In other words, the geometric center of each second basic unit and each second repeating unit coincides in plan view. It will be appreciated that the dimensions of each second basic unit are the same, and that the distance between the geometric centers of orthographic projections of any two adjacent second through holes on said second bottom surface is equal, i.e. the distance is the side length of the second basic unit. From the above analysis, it is known that the number of the second through holes per unit volume is constant in the large-mode-spot waveguide structure, that is, the distribution density of the second through holes is uniform. Each second through hole is composed of a plurality of second repeating units in the second basic units arranged along the Y direction, the geometric center of each second repeating unit in the top view is coincident with each second through hole, the axis of each second through hole is composed of the axis of each second repeating unit, and the orthographic projection of the axis of each second repeating unit on the second bottom surface is coincident with the geometric center.
In the above technical solution, the shape of the second repeating unit may be a cylinder.
In the above technical solution, the first basic unit may have the same size as the second basic unit, or the first basic unit may be different from the second basic unit in size.
In some embodiments of the present application, the distribution density of the first via holes may be the same as the distribution density of the second via holes. Specifically, the number of first through holes per unit volume of the transition waveguide structure is the same as the number of second through holes per unit volume of the large-mode-spot waveguide structure.
In other embodiments of the present application, the distribution density of the first via holes may be different from the distribution density of the second via holes. Specifically, the number of first through holes per unit volume of the transition waveguide structure is different from the number of second through holes per unit volume of the large-mode-spot waveguide structure.
In the optical waveguide structure provided by the embodiment of the application, the first through holes in the small-mode-spot waveguide structure, the transition waveguide structure and the transition waveguide structure which are distributed in an array, and the second through holes in the large-mode-spot waveguide structure and the large-mode-spot waveguide structure which are distributed in an array can be directly integrated on the silicon optical chip through silicon deposition and silicon etching processes, so that the integration level of the silicon optical chip can be effectively improved. Here, no matter the first through holes in the transition waveguide structure are in periodic arrangement, or the second through holes in the large-mode-spot waveguide structure are in periodic arrangement, because the axial directions of the first through holes and the second through holes are perpendicular to the plane where the first bottom surface or the second bottom surface is located, the first through holes and the second through holes can be realized through a silicon etching process, namely in a hole opening mode, so that the optical waveguide structure provided by the embodiment of the invention can be directly integrated on a silicon optical chip, and the manufacturing flow of the optical waveguide structure is simplified.
The embodiment of the application also provides an optical coupling structure. Referring to fig. 12, fig. 12 is a simplified top view of an optical coupling structure. As shown in fig. 12, the optical coupling structure includes a substrate 80, a silicon waveguide 70, an optical fiber 60, and the optical waveguide structure in the above technical solution, where the optical waveguide structure is disposed above the substrate 80, the silicon waveguide 70 is disposed on one side of the small-mode-spot waveguide structure 30, and the optical fiber 60 is disposed on one side of the large-mode-spot waveguide structure 20. The optical waveguide structure comprises a small-mode-spot waveguide structure 30, a transition waveguide structure 10 and a large-mode-spot waveguide structure 20 which are sequentially connected.
In the optical coupling structure, the optical signal may be output from the silicon waveguide into the optical waveguide structure, and the optical signal may be output from the optical waveguide structure into the optical fiber, where the silicon waveguide is located at an end of the optical waveguide structure that receives the optical signal, and the optical fiber is located at an end of the optical waveguide structure that outputs the optical signal. The optical signal is transmitted in the optical waveguide structure sequentially through the small-mode-spot waveguide structure, the transition waveguide structure and the large-mode-spot waveguide structure, and the arrow direction shown in fig. 12 is the propagation direction of the optical signal. In the optical coupling structure, the optical signal may be output from the optical fiber into the optical waveguide structure, and the optical signal may be output from the optical waveguide structure to the silicon waveguide, wherein the optical fiber is positioned at an end of the optical waveguide structure that receives the optical signal, and the silicon waveguide is positioned at an end of the optical waveguide structure that outputs the optical signal. The optical signal is transmitted in the optical waveguide structure sequentially through the large-mode-spot waveguide structure, the transition waveguide structure and the small-mode-spot waveguide structure.
In some embodiments of the present application, the first end face has an area that is smaller than an area of the second end face. Specifically, the size of the first end face is the same as the size of the sixth end face; the second end face has the same size as the third end face. As described above, the size of the fifth end face is the same as the size of the sixth end face, and the size of the third end face is the same as the size of the fourth end face. In other words, the area of the fifth end face is smaller than the area of the fourth end face. Specifically, the area of the fifth end face of the small-mode-spot waveguide structure is smaller than the area of the fourth end face of the large-mode-spot waveguide structure. Here, the size of the fifth end face matches the size of the silicon waveguide, and the size of the fourth end face matches the size of the optical fiber, and therefore, the area of the fifth end face is smaller than the area of the fourth end face.
In some embodiments of the present application, the refractive index of the small-mode-spot waveguide structure is the same as the refractive index of the silicon waveguide; the refractive index of the large-mode-spot waveguide structure is the same as that of the optical fiber. Specifically, the refractive index of the large-mode-spot waveguide structure is the same as that of the core in the optical fiber. For example, the transition waveguide structure may achieve a maximum range of effective refractive index of 1 to 3.42 through the periodically arranged first through holes. The large-mode-spot waveguide structure can realize any value of 1-3.42 of effective refractive index through the second through holes which are arranged periodically. Wherein the refractive index of air is 1, and the refractive index of silicon is 3.42.
Specifically, the small-mode-spot waveguide structure is connected with the silicon waveguide, the effective refractive index of the small-mode-spot waveguide structure is matched with that of the silicon waveguide, the transition waveguide structure is arranged between the small-mode-spot waveguide structure and the large-mode-spot waveguide structure so as to realize gradual change of the refractive index, and the large-mode-spot waveguide structure is connected with the optical fiber, and the effective refractive index of the large-mode-spot waveguide structure is matched with that of the optical fiber. The large-mode-spot waveguide structure realizes that the effective refractive index is matched with the optical fiber through the second through hole, so that the optical coupling structure realizes mode field matching, reduces the conversion loss of the mode field, simultaneously realizes refractive index matching, effectively reduces the reflection loss of the end face, and further improves the optical coupling efficiency.
In the optical coupling structure, the optical signal can be injected into the small-mode-spot waveguide structure by the silicon waveguide, and then the optical signal realizes the gradual change of the mode spot size in the transition waveguide structure with gradual change of the refractive index, and in the transition waveguide structure, the mode of the light is unchanged in the transition waveguide structure by matching the width of the designed waveguide, the effective refractive index distribution and the half wavelength of the light; finally, the optical signal enters the large-mode-spot waveguide structure to realize optical coupling with the optical fiber. The optical signal is emitted into the large-mode-spot waveguide structure by the optical fiber, passes through the transition waveguide structure, is emitted out of the small-mode-spot waveguide structure and enters the silicon waveguide, and the mode of the light in the transition waveguide structure is unchanged by designing the width of the transition waveguide structure, the effective refractive index distribution and the half wavelength of the light to be matched.
In comparison with the spot-size converter (spot size converter, SSC) of the related art, it is difficult to achieve refractive index matching due to the far difference in refractive index between silicon and the surrounding air or silicon dioxide. It will be appreciated that if the optical coupling structure fails to achieve index matching and mode field matching, the optical coupling efficiency of the silicon waveguide and the fiber is greatly compromised.
According to the optical coupling structure, the refractive index is controlled, and under the condition of receiving an optical signal, the refractive index matching can be achieved, so that the end face reflection loss and the mode field conversion loss are effectively reduced. The optical coupling structure provided by the embodiment of the application can have the focusing function, so that the loss is further reduced. The optical coupling structure provided in this embodiment of the present application starts from the intersection point of the extension lines of the divergence angle of the optical coupling structure provided in this embodiment of the present application (i.e., the origin O of the coordinate system shown in fig. 1) to the second end surface of the transition waveguide structure, and the optical paths of all paths are approximately equal, i.e., the error between the optical paths is smaller than the expected value. Here, near collimation means that the size of the divergence angle is far lower than an expected value within a certain distance, that is, the optical coupling structure provided by the embodiment of the application can have a focusing function, effectively reduce the divergence angle, realize near collimation, increase tolerance and reduce optical coupling difficulty.
The embodiment of the application provides a transition waveguide structure, an optical waveguide structure and an optical coupling structure, wherein the transition waveguide structure comprises: a first end face and a second end face which are parallel to each other, and a first bottom face which is perpendicular to the first end face and the second end face; the area of the first end face is smaller than that of the second end face; the first end face is used for receiving/outputting optical signals, and the corresponding second end face is used for outputting/receiving optical signals; the first through holes are distributed in an array, and the axial direction of each first through hole is perpendicular to the first bottom surface; the aperture of the first through hole increases in a direction from the first end face to the second end face. According to the transition waveguide structure, the first through holes distributed in the array are arranged, and the first through holes are formed along the direction from the first end face to the second end face, the aperture of the first through holes is increased, so that gradual change of the effective refractive index of the transition waveguide structure is realized, end face reflection loss and mode field conversion loss of the transition waveguide structure in the optical signal transmission process are reduced, and the optical coupling efficiency is improved.
It should be appreciated that reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. It should be understood that, in various embodiments of the present application, the sequence numbers of the foregoing processes do not mean the order of execution, and the order of execution of the processes should be determined by the functions and internal logic thereof, and should not constitute any limitation on the implementation process of the embodiments of the present application. The foregoing embodiment numbers of the present application are merely for describing, and do not represent advantages or disadvantages of the embodiments.
The foregoing description is only of the preferred embodiments of the present application, and is not intended to limit the scope of the claims, and all equivalent structural changes made by the specification and drawings of the present application or direct/indirect application in other related technical fields are included in the scope of the claims of the present application.
Claims (10)
1. A transition waveguide structure, comprising: a first end face and a second end face which are parallel to each other, and a first bottom face which is perpendicular to the first end face and the second end face; the area of the first end face is smaller than that of the second end face; the first end face is used for receiving/outputting optical signals, and the corresponding second end face is used for outputting/receiving optical signals;
the first through holes are distributed in an array, and the axial direction of each first through hole is perpendicular to the first bottom surface; the aperture of each first through hole is reduced along the direction pointing to the first bottom surface;
the aperture of the first through hole increases in a direction from the first end face to the second end face.
2. The transition waveguide structure of claim 1, wherein the first through-holes are mirror symmetric along a central axis of the transition waveguide structure and the aperture of the first through-holes increases in a direction away from the central axis.
3. The transition waveguide structure of claim 1, wherein each of the first through holes is stacked in an axial direction from a plurality of repeating units.
4. A transition waveguide structure according to claim 3, wherein the shape of the repeating unit comprises a cylinder, a truncated cone, a cuboid, a truncated pyramid, or a regular polyhedron.
5. The transition waveguide structure of claim 1, wherein the distance between the axes of any adjacent two of the first through holes is equal.
6. An optical waveguide structure, comprising: a small-mode patch waveguide structure, a large-mode patch waveguide structure, and a transition waveguide structure according to any one of claims 1 to 5; the transition waveguide structure is arranged between the small-mode-spot waveguide structure and the large-mode-spot waveguide structure.
7. The optical waveguide structure of claim 6 wherein the large mode spot waveguide structure comprises: a third end face and a fourth end face parallel to each other; the third end face and the fourth end face are equal in size;
the large-mode-spot waveguide structure is provided with second through holes distributed in an array, and the axial direction of each second through hole is parallel to the third end face;
The second end face and the third end face are equal in size.
8. The optical waveguide structure of claim 6 wherein the small-mode-spot waveguide structure comprises: a fifth end face and a sixth end face parallel to each other; the fifth end face and the sixth end face are equal in size;
the sixth end face is equal in size to the first end face.
9. An optical coupling structure, comprising: a substrate, a silicon waveguide, an optical fiber, and an optical waveguide structure as claimed in any one of claims 6 to 8;
the optical waveguide structure is arranged above the substrate;
the silicon waveguide is arranged on one side of the small-mode-spot waveguide structure, and the optical fiber is arranged on one side of the large-mode-spot waveguide structure.
10. The optical coupling structure of claim 9 wherein the refractive index of the small-mode-spot waveguide structure is the same as the refractive index of the silicon waveguide; the refractive index of the large-mode-spot waveguide structure is the same as that of the optical fiber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111181872.9A CN114114530B (en) | 2021-10-11 | 2021-10-11 | Transition waveguide structure, optical waveguide structure and optical coupling structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111181872.9A CN114114530B (en) | 2021-10-11 | 2021-10-11 | Transition waveguide structure, optical waveguide structure and optical coupling structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114114530A CN114114530A (en) | 2022-03-01 |
| CN114114530B true CN114114530B (en) | 2023-08-04 |
Family
ID=80441924
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111181872.9A Active CN114114530B (en) | 2021-10-11 | 2021-10-11 | Transition waveguide structure, optical waveguide structure and optical coupling structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114114530B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6856737B1 (en) * | 2003-08-27 | 2005-02-15 | Mesophotonics Limited | Nonlinear optical device |
| JP2005062664A (en) * | 2003-08-19 | 2005-03-10 | Japan Aviation Electronics Industry Ltd | Two-dimensional photonic crystall optical device and its manufacturing method |
| CN203241564U (en) * | 2013-05-30 | 2013-10-16 | 青岛海信宽带多媒体技术有限公司 | Optical fiber waveguide spot size converter and optical coupler |
| CN106154428A (en) * | 2015-03-30 | 2016-11-23 | 青岛海信宽带多媒体技术有限公司 | A kind of bonder |
| CN107329209A (en) * | 2017-08-18 | 2017-11-07 | 中国科学院半导体研究所 | M × N multicast photoswitches |
| CN214225478U (en) * | 2020-12-02 | 2021-09-17 | 苏州旭创科技有限公司 | Photon integrated chip and coupling structure thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10976496B2 (en) * | 2019-02-11 | 2021-04-13 | Poet Technologies, Inc. | Dual core waveguide |
-
2021
- 2021-10-11 CN CN202111181872.9A patent/CN114114530B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005062664A (en) * | 2003-08-19 | 2005-03-10 | Japan Aviation Electronics Industry Ltd | Two-dimensional photonic crystall optical device and its manufacturing method |
| US6856737B1 (en) * | 2003-08-27 | 2005-02-15 | Mesophotonics Limited | Nonlinear optical device |
| CN203241564U (en) * | 2013-05-30 | 2013-10-16 | 青岛海信宽带多媒体技术有限公司 | Optical fiber waveguide spot size converter and optical coupler |
| CN106154428A (en) * | 2015-03-30 | 2016-11-23 | 青岛海信宽带多媒体技术有限公司 | A kind of bonder |
| CN107329209A (en) * | 2017-08-18 | 2017-11-07 | 中国科学院半导体研究所 | M × N multicast photoswitches |
| CN214225478U (en) * | 2020-12-02 | 2021-09-17 | 苏州旭创科技有限公司 | Photon integrated chip and coupling structure thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114114530A (en) | 2022-03-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3581224B2 (en) | Planar optical waveguide device | |
| JP5747384B2 (en) | Multi-layer waveguide type optical input / output terminal | |
| US20040184156A1 (en) | Polarization splitting grating couplers | |
| US7269310B2 (en) | Optical connector, optical coupling method and optical element | |
| CN111090148A (en) | Multi-core optical fiber multiplexing and demultiplexing device and method based on super-surface lens | |
| WO2021103530A1 (en) | Two-dimensional scalable superconducting qubit structure and cavity mode control method therefor | |
| US10481328B1 (en) | Optical phased array with integrated secondary optics | |
| CN110989088A (en) | Multiplexing/demultiplexing device and method based on lens and super-surface lens | |
| US9784915B2 (en) | Cross-shaped infrared polarized light bridge based on photonic crystal waveguide | |
| CN116413856B (en) | End face coupler and preparation method thereof | |
| CN114114530B (en) | Transition waveguide structure, optical waveguide structure and optical coupling structure | |
| WO2003079053A2 (en) | High density integrated optical chip with low index difference and high index difference waveguide functions | |
| US20240012202A1 (en) | Metasurface-based optical signal manipulation devices for optical fiber communications | |
| US20030146187A1 (en) | Optical element and method for manufacturing same | |
| CN109709641B (en) | Multimode cross structure based on periodic dielectric waveguide and design method thereof | |
| CN218003774U (en) | Dual-mode multi-channel cross waveguide | |
| CN114217380B (en) | End face coupler and preparation method thereof | |
| US7031565B2 (en) | Photonic switch | |
| US11822122B2 (en) | Waveguide structures | |
| WO2022169700A1 (en) | Compact dual polarization couplers for multi-core optical fibers | |
| US20040047557A1 (en) | Microlens array, optical module using the microlens array, and method for determining position of optical module | |
| CN1217207C (en) | Optical-wave-division duplexer/deduplexer based on 2-D distribution array wave-guide optical grating | |
| DE112021003699T5 (en) | emitter array | |
| CN111025482A (en) | Mode efficient coupler and preparation method thereof | |
| CN116224475B (en) | Light converter and light conversion system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |