WO2018149412A1

WO2018149412A1 - Optical path modification method, and method of manufacturing optical grating for modifying optical path

Info

Publication number: WO2018149412A1
Application number: PCT/CN2018/076799
Authority: WO
Inventors: 高宇琦
Original assignee: 中兴通讯股份有限公司
Priority date: 2017-02-20
Filing date: 2018-02-14
Publication date: 2018-08-23
Also published as: CN108459366A

Abstract

An optical path modification method comprises: diffracting, using a curved optical grating (302) at an optical waveguide, a wave of light to be diffracted, so as to output the diffracted wave of light having a preset angle with respect to the wave of light to be diffracted. Also disclosed is a method of manufacturing an optical grating for modifying an optical path.

Description

Method of changing optical path, and method for manufacturing grating for changing optical path

Technical field

The present disclosure relates to the field of communications, for example, to a method of changing an optical path, and a method of fabricating a grating for changing an optical path.

Background technique

With the explosive growth of communication system requirements for transmission rates, copper interconnects have faced bottlenecks in development, and optical interconnects are solutions for achieving high-speed interconnects of the Tbit/s scale. The technical realization of optical interconnection is usually to integrate an optical waveguide into a PCB to form a photovoltaic panel, that is, an optical backplane. In optical backplane communication, the connection between the daughter board and the optical backplane requires a 90 degree turn of the optical path. In the related art, a 45 degree prism reflection is generally used to achieve a 90 degree turn of the optical path. Fig. 1 is a schematic diagram showing the vertical coupling of an optical path in the related art. As shown in FIG. 1, the incident light 201 of the optical waveguide 101 is reflected by the 45-degree prism 301, and the optical path of the outgoing light 202 is changed by 90 degrees and coupled into the optical waveguide 101. However, since the optical waveguides are of the order of micrometers, the fabrication of prisms having a micrometer of 45 degrees is low, and the installation of prisms of 45 degrees is highly demanding, which is not conducive to mass production.

Summary of the invention

The present disclosure provides a method of changing an optical path, and a method of fabricating a grating for changing an optical path, to at least solve the problem of achieving difficulty in optical path turning due to difficulty in fabricating a prism of a micron order of 45 degrees in the related art.

A method for changing an optical path, comprising: a diffracted light wave whose diffraction wave passes through a curved grating on the optical waveguide and whose angle between the diffraction output and the optical wave to be diffracted is a predetermined angle.

In an embodiment, the curvilinear grating is concave on a side facing the incident direction of the light wave to be diffracted.

In an embodiment, the method further comprises: determining the curvilinear grating according to a curvilinear grating model, wherein the curvilinear grating model is obtained from a simulation model established according to a preset parameter, and the curvilinear grating The light wave coupling efficiency when the model simulates the diffracted light wave is not less than 80%.

In an embodiment, the preset parameter includes at least one of: a refractive index parameter of the optical waveguide, a refractive index parameter of a substrate of the optical waveguide, a wavelength of the optical wave to be diffracted, and the pre- Set the angle.

In an embodiment, the determining the curved grating according to the curved grating model comprises: engraving the curved grating on the optical waveguide by using a holographic image method according to the curved grating model.

In one embodiment, the manner of engraving the curvilinear grating on the optical waveguide by using a holographic image method includes one of: drawing a linear grating on the optical waveguide using the holographic image method, Pressing the upper and lower sides of the linear grating and the side facing the incident direction of the light wave to be diffracted, and engraving a curved grating facing the incident direction of the light wave to be diffracted; setting above the optical waveguide A convex type light-shielding sheet is formed on the optical waveguide provided with the convex light-shielding sheet by the holographic image method, and a curved grating which is concave toward the incident direction of the light wave to be diffracted is drawn.

In an embodiment, the curvilinear grating is a curved chirped grating.

A method for fabricating a grating for changing an optical path, comprising:

Establishing a simulation model according to the preset parameter, and obtaining a curved grating model by using the simulation model, wherein the curved grating model simulates the diffracted light wave with an optical wave coupling efficiency of not less than 80%;

Forming the curved grating on the optical waveguide according to the curved grating model, the curved grating is such that the angle between the diffraction output of the curved wave to be diffracted and the optical wave to be diffracted is a preset angle Diffraction light wave.

In an embodiment, the curvilinear grating is engraved on the optical waveguide according to the curvilinear grating model, comprising at least one of: engraving on the optical waveguide using a holographic image method according to the curvilinear grating model a linear grating which is pressed on the upper and lower sides of the linear grating and on the side facing the incident direction of the light wave to be diffracted, and a curved grating which is concave toward the incident direction of the light wave to be diffracted is engraved; A convex type light shielding sheet is disposed above the optical waveguide, and according to the curved grating model, a holographic image method is used to engrave an optical waveguide provided with the convex light shielding sheet on a side facing the incident direction of the light wave to be diffracted Curved grating.

An optical waveguide device comprising a curved grating engraved on the optical waveguide device, wherein the curved grating causes an angle between a diffraction output of the optical fiber to be diffracted passing through the curved grating and the optical wave to be diffracted to be Set the angle of the diffracted light wave.

In an embodiment, the curvilinear grating is determined according to a curvilinear grating model obtained from a simulation model established according to a preset parameter, and the curved grating model simulating the diffracted light wave The light wave coupling efficiency is not less than 80%.

An optical backplane comprising the above optical waveguide device, the optical waveguide device being disposed on the optical backplane.

Through the present disclosure, a pre-made curved grating is applied to the transmission process of the light wave, and the diffracted light wave to be diffracted through the diffraction grating of the curved grating and the diffracted light wave at a predetermined angle. The use of a curved grating diffracted light wave, in the case of ensuring a high coupling ratio of light waves after diffraction, changes the direction of the optical path, replacing the micron-sized prism, thereby solving the difficulty in fabricating a micron-sized 45-degree prism in the related art. Achieving the problem of difficult road transition.

DRAWINGS

The drawings described herein are provided to provide an understanding of the present disclosure and constitute a part of this disclosure.

1 is a schematic diagram of a vertical coupling of an optical path in the related art;

2a is a flow chart of a method for changing an optical path according to an embodiment;

2b is a flow chart of a method for changing an optical path according to another embodiment

3 is a flow chart of a method for fabricating a grating for changing an optical path according to an embodiment;

4 is a structural diagram of a linear grating for changing an optical path according to an embodiment;

Figure 5a is a structural diagram of a curved grating for optical path change according to an embodiment;

Figure 5b is a schematic diagram of a curve of a constituent curved grating of an embodiment;

6a is a schematic exploded view of an optical path of a curved grating facing a side of an incident direction of a light wave according to an embodiment;

FIG. 6b is a schematic diagram of a concave curved surface concentrated light on one side of the incident direction of the light wave according to an embodiment; FIG.

Figure 7 is a schematic view showing a curved grating changing optical path of an embodiment;

Figure 8 is a front elevational view of a curved grating changing optical path of an embodiment;

9 is a schematic diagram of a first method for fabricating a curved grating according to an embodiment;

10 is a schematic diagram of a second embodiment of a curved grating produced by an embodiment;

Figure 11 is a flow chart of changing an optical path by a curved grating according to an embodiment;

Figure 12 is a schematic view of an embodiment of an optical waveguide array vertically coupled to an optical fiber array;

13 is a schematic diagram 2 of an optical waveguide array vertically coupled to an optical fiber array according to an embodiment;

Figure 14 is a schematic view of an embodiment of an optical waveguide array vertically coupled to an optical waveguide array;

15 is a schematic diagram 2 of an optical waveguide array vertically coupled to an optical waveguide array according to an embodiment;

Figure 16 is a schematic view of an embodiment of an optical waveguide array vertically coupled to a detector array;

17 is a schematic diagram 2 of an optical waveguide array vertically coupled to a detector array according to an embodiment;

Figure 18 is a schematic view of a laser array of an embodiment vertically coupled to an optical waveguide array;

19 is a schematic diagram 2 of a laser array vertically coupled to an optical waveguide array according to an embodiment;

Figure 20 is a schematic view 1 of an optical backplane system according to an embodiment;

21 is a second schematic view of an optical backplane system according to an embodiment.

detailed description

The present disclosure will be hereinafter described with reference to the drawings in conjunction with the embodiments.

The terms "first", "second" and the like in the specification and claims of the present embodiment and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or order.

In accordance with an embodiment of the present disclosure, a method of changing an optical path is provided.

2a is a flow chart of a method for changing an optical path according to an embodiment. As shown in FIG. 2a, the flow includes the following steps.

In step 200, the diffracted light wave passing through the curved grating on the optical waveguide and the diffracted optical wave are at a predetermined angle.

2b is a flow chart of a method for changing an optical path according to another embodiment. As shown in FIG. 2b, the flow includes the following steps.

In step 202, a curved grating is engraved on the optical waveguide according to a preset curved grating model.

In step 204, the diffracted light wave passing through the curved grating on the optical waveguide and the diffracted light wave are at a predetermined angle.

Through the above steps, the pre-made curved grating is applied to the transmission process of the light wave, and the diffracted light wave to be diffracted by the diffraction grating of the curved grating and the diffracted light wave at a predetermined angle. The use of a curved grating to diffract light waves ensures that the optical path of the diffracted light is high, and the optical path is changed to replace the micron-sized prism, thereby solving the difficulty in fabricating a micron-sized 45-degree prism in the related art. The problem of achieving difficult turning of the light path.

In an embodiment, the method for changing an optical path provided by the embodiment further includes: determining the curved grating according to a curved grating model, wherein the curved grating model is obtained from a simulation model established according to preset parameters. And the light-wave coupling efficiency when the curved grating model simulates the diffracted light wave is not less than 80%.

In an embodiment, the curvilinear grating determines the curvilinear grating according to a curvilinear grating model, comprising: engraving the curvilinear pattern on the optical waveguide by using a holographic image method according to the curvilinear grating model Grating.

In one embodiment, the manner of engraving the curvilinear grating on the optical waveguide by using a holographic image method includes one of: drawing a linear grating on the optical waveguide using a holographic image method, in the linear grating Pressing the upper and lower sides and the side facing the incident direction of the light wave to be diffracted, and engraving a curved grating concave toward the incident direction of the light wave to be diffracted; and providing a convex light shielding film above the optical waveguide A curved grating which is concave on the side of the incident direction of the light wave to be diffracted is formed on the optical waveguide provided with the convex type light shielding sheet by using a holographic image method.

In an embodiment, the curvilinear grating is a curved chirped grating.

According to another embodiment of the present disclosure, a method of fabricating a grating for changing an optical path is provided.

FIG. 3 is a flow chart of a method for fabricating a grating for changing an optical path according to an embodiment. As shown in FIG. 3, the flow includes the following steps.

In step 302, a simulation model is established according to the preset parameters, and the curved grating model is obtained by the simulation model, wherein the curved grating model simulates the diffracted light wave with an optical wave coupling efficiency of not less than 80%.

In step 304, the curvilinear grating is engraved on the optical waveguide according to the curvilinear grating model.

Wherein, the curved grating causes the diffracted light wave to be diffracted by the diffracted output of the curvilinear grating and the diffracted optical wave to be a predetermined angle.

In an embodiment, the preset parameter comprises at least one of: a refractive index parameter of the optical waveguide, a refractive index parameter of a substrate of the optical waveguide, a wavelength of a light wave to be diffracted, and a preset angle.

In an embodiment, the curvilinear grating is engraved on the optical waveguide according to the curvilinear grating model, comprising at least one of: engraving on the optical waveguide using a holographic image method according to the curvilinear grating model a linear grating which is pressed on the upper and lower sides of the linear grating and on the side facing the incident direction of the light wave to be diffracted, and a curved grating which is concave toward the incident direction of the light wave to be diffracted is engraved; A convex type light shielding sheet is disposed above the optical waveguide, and according to the curved grating model, a curved type concave on a side opposite to an incident direction of the light wave to be diffracted is formed on the optical waveguide provided with the light shielding sheet by using a holographic image method Grating.

The embodiment further provides an optical waveguide device including a curved grating carved on the optical waveguide device, the curved grating passing the diffraction wave of the light to be diffracted through the curved grating and the optical wave to be diffracted The diffracted light wave whose angle is a preset angle. The optical waveguide device can be referred to all of the drawings having the optical waveguide device, for example, referring to the optical waveguide array 101 in FIG.

The above will be described below in conjunction with the present embodiment. In this embodiment, a curved 啁啾 grating is used, and the angle of change of the light wave is 90 degrees as an example.

In the embodiment, according to the characteristic that the curved chirped grating has the function of changing the optical path and concentrating the light, a method and a device for vertically coupling the optical waveguide to the optical waveguide and the optical waveguide to the optical fiber are coupled by using the curved chirped grating. In order to improve the efficiency of vertical coupling and reduce the difficulty and manufacturing process of vertical coupling of optical waveguides. That is, the application of the curved chirped grating has the characteristics of changing the optical path and concentrating the light to realize the 90 degree steering of the optical path, realizing the vertical coupling of the optical waveguide to the optical waveguide and the vertical coupling of the optical waveguide to the optical fiber.

In the related art, for a light wave having a wavelength of λ, the diffraction direction of the grating should satisfy the following equation.

d(sinα±sinβ)=mλ(m is a positive integer) Formula (1)

In the above equation: d represents the distance between two adjacent engraved lines, called the grating constant; α is the incident angle; that is, the angle between the incident beam and the grating normal; the β diffraction angle, that is, the angle between the diffracted beam and the grating normal, m The diffraction order of the wavelength.

In the analysis formula (1), in the case where the α incident angle and the wavelength λ are fixed, the grating constant d determines the direction of the diffraction angle β, and thus it can be seen that the grating has a characteristic of changing the optical path. 4 is a structural diagram of an embodiment of a linear grating for changing an optical path. Fig. 5a is a structural diagram of a curved grating for optical path change according to an embodiment, and Fig. 5b is a schematic diagram of a curved grating constituting an embodiment. As shown in Fig. 5a, the grating is a curved grating which is concave on one side of the incident direction of the light wave. Since the grating designed in this embodiment has a concave arc on the side of the incident direction of the light wave, the optical path is also changed while the light path is changed, thereby improving the efficiency of the optical coupling, and FIGS. 6a and 6b are FIG. 6a is a schematic diagram of optical path decomposition of a curved grating that is concave on the side of the incident direction of the light wave, and FIG. 6a is a schematic diagram of the change of the direction of the optical path of the grating according to an embodiment. As shown in FIG. 6a, at a local position, Curve-type grating When a linear grating is analyzed, the effect of the curved grating on the optical path can be analyzed; FIG. 6b is a schematic diagram of a convex curved surface of the concave surface facing the incident direction of the light wave according to an embodiment, as shown in FIG. 6b. A curve of the curved grating can be analyzed to analyze the convergence of the curved grating on the optical path.

The method of the curved grating of this embodiment includes the following steps.

1) Calculate the range of the grating constant according to the material of the optical waveguide, the wavelength of the light wave, and the angle at which the light wave needs to be changed. Among them, the light wave refers to the light wave to be diffracted.

2) According to the material of the optical waveguide, the wavelength of the light wave, and the range of the grating constant, a simulation model is established. On the basis of the simulation model, a concave curved grating facing the incident direction of the light wave is simulated, and the curvature and interval of the grating are repeatedly adjusted. , a grating model with coupling efficiency ≥ 80% is obtained.

3) According to the curved grating model, a curved grating is carved on the optical waveguide by a holographic image method. The holographic grating is fabricated by two beams of light having a specific wavefront shape, forming interference fringes between bright and dark phases on the recording plane, recording interference fringes with a holographic recording medium, and processing to obtain a holographic grating.

There are two methods for fabricating a curved grating in this embodiment.

(1) One method is to first scribe a linear grating on a light waveguide by a holographic image method, and then pressurize both sides of the optical waveguide on which the linear grating is engraved, and FIG. 9 is a first embodiment of a curved pattern. A schematic diagram of the grating, as shown in Fig. 9, engraves a curved grating which is concave on one side facing the incident direction of the light wave.

(2) Another method is to place a convex light-shielding sheet on the optical waveguide as shown in FIG. 10, that is, FIG. 10 is a schematic view of a second embodiment of the curved grating, and then used thereon. In the holographic image method, since a change in the optical path difference is caused by placing a convex light-shielding sheet on the optical waveguide, a curved grating which is concave on the side in the incident direction of the light wave is generated.

7 is a schematic diagram of a curved grating changing optical path of an embodiment, and FIG. 8 is a front view of a curved grating changing optical path of an embodiment. As shown in FIG. 7 and FIG. 8, the apparatus for changing an optical path provided by the embodiment is mainly The substrate layer 100 includes a ridge type optical waveguide 101 recorded on the substrate layer, and a curved erbium grating 302 recorded on the optical ridge type optical waveguide, wherein the recording is concave on the side of the optical ridge type optical waveguide facing the incident direction of the light wave. The curved chirped grating 302 is the core device of the device for achieving a 90 degree turn of the optical path and coupling of the optical path.

11 is a flow chart of changing an optical path by a curved grating according to an embodiment. As shown in FIG. 11, the flow includes the following steps.

In step 1102, a ridge-type optical waveguide display is fabricated on the substrate.

In step 1104, the wavelength of the light wave is transmitted according to the refractive index of the substrate and the waveguide material, and a high-efficiency curved 啁啾 grating is calculated, and a simulation model is established based on the calculated result.

In step 1106, a curved grating is designed according to the simulation model, and the curvature and spacing of the grating are repeatedly adjusted to obtain a grating model with a coupling efficiency of ≥80%.

In step 1108, a curved chirped grating is engraved on the ridge-type optical waveguide using a holographic image forming technique in accordance with the established grating model.

In step 1110, the engraved curved 啁啾 grating is applied to the vertical coupling of the optical waveguide to the optical waveguide, and the vertical coupling of the optical waveguide to the optical fiber to achieve vertical coupling of the optical waveguide to the optical waveguide, and optical waveguide to optical fiber Vertical coupling.

The technical solution adopted in this embodiment includes the following steps.

1) Calculate the simulation model and simulate the model of the curved 啁啾 grating according to the simulation model.

2) According to the experimental curved 啁啾 grating model concave on the side of the incident direction of the light wave, the curved 啁啾 grating is carved on the ridge type optical waveguide display by using holographic image technology.

3) The vertical coupling of the optical waveguide to the optical waveguide and the vertical coupling of the optical waveguide to the optical fiber are realized by using the curved curved chirped grating.

By adopting the method and device described in the embodiment, compared with the related art, the vertical coupling of the optical waveguide to the optical waveguide and the difficulty of the vertical coupling of the optical waveguide to the optical fiber and the manufacturing process are reduced.

Embodiment 1 FIG. 12 is a first schematic diagram of an optical waveguide array of an embodiment vertically coupled to an optical fiber array. As shown in FIG. 12, the optical waveguide array 101 is horizontally placed, and the curved chirped grating 302 is engraved on the optical waveguide. A vertically fixed ribbon fiber 102. FIG. 13 is a second schematic diagram of an optical waveguide array vertically coupled to an optical fiber array according to an embodiment. As shown in FIG. 13, when the light 201 propagating through the optical waveguide 101 passes through the curved chirped grating 302, the curved chirped grating 302 is paired. The diffraction effect of the light changes the propagation path of the light, causing the optical path to turn 90 degrees. At the same time, due to the convergence effect of the curved chirped grating 302 on the light, the outgoing light 202 can be efficiently coupled into the vertically fixed optical fiber 102 to realize the light. Vertical coupling of the waveguide to the fiber.

Embodiment 2: FIG. 14 is a first schematic diagram of an optical waveguide array of an embodiment vertically coupled to an optical waveguide array. As shown in FIG. 14, a horizontally-shaped optical waveguide array 101 is disposed, and a curved 啁啾 grating 302 engraved on the optical waveguide is illustrated. , a vertically fixed optical waveguide array 101. 15 is a schematic diagram 2 of an optical waveguide array of an embodiment vertically coupled to an optical waveguide array. As shown in FIG. 15, when the light 201 propagating through the optical waveguide 101 passes through the curved chirped grating 302, the curved chirped grating 302 is used. The diffractive effect on the light changes the propagation path of the light, causing the optical path to turn 90 degrees. At the same time, due to the convergence effect of the curved chirped grating 302 on the light, the outgoing light 202 can be efficiently coupled into the vertical optical waveguide array 101. Vertical coupling of the optical waveguide to the waveguide.

Embodiment 3: FIG. 16 is a first schematic diagram of an optical waveguide array of an embodiment vertically coupled to a detector array. As shown in FIG. 16, a horizontally disposed optical waveguide array 101 is disposed, and a curved 啁啾 grating 302 engraved on the optical waveguide is illustrated. , a vertically fixed detector array. 17 is a schematic diagram 2 of an optical waveguide array vertically coupled to a detector array according to an embodiment. As shown in FIG. 17, when the incident light 201 propagating through the optical waveguide 101 passes through the curved chirped grating 302, the curved chirped grating is used. The diffracting effect of 302 on the light changes the propagation path of the light, causing the optical path to turn 90 degrees. At the same time, due to the convergence effect of the curved chirped grating 302 on the light, the outgoing light 202 can be efficiently coupled into the detector array to realize light. The waveguide is directly coupled to the detector array vertically.

Embodiment 4: FIG. 18 is a first schematic diagram of a laser array vertically coupled to an optical waveguide array according to an embodiment. As shown in FIG. 18, the optical waveguide array 101 is horizontally placed, and the curved chirped grating 302 is engraved on the optical waveguide. Vertically fixed VESEL laser array. 19 is a schematic diagram 2 of a VESEL laser array vertically coupled to an optical waveguide array, as shown in FIG. 19, when the light 201 emitted by the vertically fixed VESEL laser array passes through the curved chirped grating 302, due to the curved chirped grating The diffraction effect of 302 on the light changes the propagation path of the light, causing the optical path to turn 90 degrees, and because the curved chirped grating 302 has a converging effect on the light, the outgoing light 202 can be efficiently coupled to the horizontally placed optical waveguide array 101. The vertical coupling of the VESEL laser array directly to the optical waveguide array is achieved.

Embodiment 5: FIG. 20 is a schematic diagram of an optical backplane system according to an embodiment. As shown in FIG. 20, a sub-board 1, a sub-board 2, an optical backplane, and a VESEL laser array 104 disposed on the sub-board 1 are provided. The array 101, the detector array 103 placed on the sub-board 2, the optical waveguide array 101, the optical waveguide array 101 placed on the optical backplane, and the curved chirped grating 302 recorded at both ends of the optical waveguide array. FIG. 21 is a second schematic diagram of an optical backplane system according to an embodiment. As shown in FIG. 21, the light 201 emitted from the VESEL laser array fixed to the sub-board 1 is first coupled to the optical waveguide array 101 on the sub-board 1 through the sub-board. The optical waveguide array 101 on 1 is transmitted to the first curved 啁啾 grating 302 on the optical waveguide array 101 of the optical backplane, and the optical path occurs due to the diffraction effect of the curved 啁啾 grating 302 on the light. The 90 degree transition, and at the same time, due to the convergence effect of the curved chirped grating 302 on the light, the outgoing light 202 can be efficiently coupled into the optical waveguide array 101 on the optical backplane, and transmitted to the optical backplane through the optical waveguide array 101 of the optical backplane. The second curved 啁啾 grating 302 on the optical waveguide array 101 changes the light propagation path due to the diffraction effect of the curved 啁啾 grating 302 on the light, causing the optical path to be rotated by 90 degrees, and at the same time due to the curved 啁啾 grating 302 There is a convergence effect on the light, so that the outgoing light 202 can be efficiently coupled to the optical waveguide array 101 on the sub-board 2, and then transmitted to the photodetector array 401 via the optical waveguide array 101 on the sub-board 2 to complete the entire system. Light transmission.

The method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course also by hardware. The embodiment may be embodied in the form of a software product stored in a storage medium (such as a ROM/RAM, a magnetic disk, or an optical disk), and includes a plurality of instructions for causing a terminal device (which may be a mobile phone, The computer, server, or network device, etc.) performs the method described in this embodiment.

The various modules or steps of the present disclosure described above may be implemented by a general-purpose computing device, which may be centralized on a single computing device or distributed over a network of multiple computing devices. In one embodiment, they may Implemented by program code executable by the computing device, such that they can be stored in a storage device for execution by the computing device, and in some cases, the steps shown or described can be performed in a different order than the ones described herein. Alternatively, they may be fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof may be fabricated into a single integrated circuit module.

Industrial applicability

The method for changing the optical path provided by the present disclosure applies a pre-made curved grating to the transmission process of the light wave, and the diffracted light wave to be diffracted by the diffraction grating of the curved grating and the diffraction wave at a predetermined angle between the diffraction grating and the diffracted optical wave The use of a curved grating diffracted light wave, in the case of ensuring a high coupling ratio of light waves after diffraction, changes the direction of the optical path, replacing the micron-sized prism, thereby solving the difficulty in fabricating a micron-sized 45-degree prism in the related art. The problem of achieving difficult turning of the light path.

Claims

A method of changing the optical path, comprising:

The diffracted light wave of the curved grating to be diffracted through the optical waveguide and the diffracted optical wave at an angle of a predetermined angle.
The method according to claim 1, wherein said curvilinear grating is concave on a side facing an incident direction of said light wave to be diffracted.
The method of claim 2, further comprising: determining the curvilinear grating according to a curvilinear grating model, wherein the curvilinear grating model is obtained from a simulation model established according to a preset parameter, and the curvilinear grating The light wave coupling efficiency when the model simulates the diffracted light wave is not less than 80%.
The method of claim 3, wherein the preset parameters comprise at least one of the following:

a refractive index parameter of the optical waveguide, a refractive index parameter of a substrate of the optical waveguide, a wavelength of the optical wave to be diffracted, and the predetermined angle.
The method according to claim 3 or 4, wherein said determining said curved grating according to a curved grating model comprises:

According to the curvilinear grating model, the curvilinear grating is engraved on the optical waveguide by a holographic image method.
The method according to claim 5, wherein said means for engraving said curved grating on said optical waveguide by holographic image method comprises one of the following:

Using the holographic image method to inscribe a linear grating on the optical waveguide, pressurizing on the upper and lower sides of the linear grating and on the side of the incident direction facing the light wave to be diffracted, and engraving the light wave to be diffracted a curved grating concave on one side of the incident direction;

Providing a convex type light shielding sheet over the optical waveguide, and using the holographic image method, a curved grating concave on a side facing an incident direction of the light wave to be diffracted is formed on an optical waveguide provided with the convex light shielding sheet .
The method of any of claims 1-6, wherein the curvilinear grating is a curved chirped grating.
A method for fabricating a grating for changing an optical path, comprising:

Establishing a simulation model according to the preset parameter, and obtaining a curved grating model by using the simulation model, wherein the curved grating model simulates the diffracted light wave with an optical wave coupling efficiency of not less than 80%;

And forming a curved grating on the optical waveguide according to the curved grating model, wherein the curved grating causes diffraction of the diffraction wave to be diffracted through the curved grating and the diffraction angle of the optical wave to be diffracted to be a predetermined angle Light waves.
The method of claim 8, wherein the preset parameters comprise at least one of the following:

a refractive index parameter of the optical waveguide, a refractive index parameter of a substrate of the optical waveguide, a wavelength of the optical wave to be diffracted, and the predetermined angle.
The method of claim 8, wherein the patterning the grating on the optical waveguide according to the curvilinear grating model comprises at least one of the following:

According to the curvilinear grating model, a linear grating is engraved on the optical waveguide by using a holographic image method, and is pressed on the upper and lower sides of the linear grating and on the side of the incident direction facing the light wave to be diffracted, and the face is facing a curved grating concave on one side of the incident direction of the diffracted light wave;

A convex type light shielding sheet is disposed above the optical waveguide, and according to the curved grating model, a side of an incident direction facing the light wave to be diffracted is carved on the optical waveguide provided with the convex type light shielding sheet by using a holographic image method A concave curved grating.
An optical waveguide device comprising a curved grating engraved on the optical waveguide device, wherein the curved grating causes an angle between a diffraction output of the optical fiber to be diffracted passing through the curved grating and the optical wave to be diffracted to be Set the angle of the diffracted light wave.
The optical waveguide device according to claim 11, wherein said curved grating is concave on a side facing an incident direction of said light wave to be diffracted.
The optical waveguide device according to claim 12, wherein said curved grating is determined according to a curved grating model obtained from a simulation model established according to a preset parameter, and said curved grating model The light wave coupling efficiency when simulating the diffracted light wave is not less than 80%.
The optical waveguide device according to claim 13, wherein said preset parameter comprises at least one of the following:

a refractive index parameter of the optical waveguide, a refractive index parameter of a substrate of the optical waveguide, a wavelength of the optical wave to be diffracted, and the predetermined angle.
An optical backplane comprising the optical waveguide device of any of claims 11-14, the optical waveguide device being disposed on the optical backplane.