Optical waveguide and beam-assisted alignment method

Abstract

The present application discloses an optical waveguide and a method for auxiliary alignment of light beams. An optical waveguide includes a substrate, a cladding, and a core layer. The cladding covers the core layer and is arranged on the substrate; these three parts form an open groove. The groove includes two surfaces arranged opposite to each other. The portion of one surface on the core layer is a first inclined surface, and the portion of the other surface on the core layer is a second inclined surface. The first and second inclined surfaces are reflective surfaces. The core layer includes a first core layer and a second core layer arranged on both sides of the groove, each including a first and a second inclined surface. The first inclined surface is used to change the transmission path of the signal light or continuous light in the optical waveguide so as to output along the second direction or transmit along the first core layer. The second inclined surface is used to change the transmission path of the auxiliary alignment light in the optical waveguide so as to output along the third direction or transmit along the second core layer. The second direction and the third direction are toward the same side of the substrate. With the help of the transmission optical path of the auxiliary alignment light, the optical waveguide can achieve fast and low-cost coupling alignment.

Description

Technical Field

[0001] The present invention relates to the field of optical devices, and in particular to an optical waveguide, an optical transmission system and a light beam auxiliary alignment method. Background Art

[0002] Optical waveguides are key components in optical communication systems, used to transmit an input optical beam to another component. Optical waveguides, such as vertical reflective waveguides, can simultaneously redirect and transmit a beam. Achieving beam alignment between the waveguide and its associated component—ensuring that a beam transmitted through the waveguide fully or in large part reaches its associated component—is a key research topic in the research and commercialization of optical waveguides.

[0003] Figure 1 Figure 1 is a schematic diagram of a system including an existing vertical reflection waveguide. Figure 1 As shown, the system includes a vertical reflection waveguide 100 and an optical receiving device 200. The vertical reflection waveguide 100 includes a substrate 101 and a core layer 103 and a cladding layer 102 arranged on the substrate 101. The core layer 103 is used to transmit a light beam (for example, Figure 1 The core layer 103 and the cladding layer 102 form a Figure 1 As shown in the groove, one side of the groove is used to reflect incident light so that the incident light is transmitted to the light receiving device 200 .

[0004] In use Figure 1 Before the illustrated system begins beam transmission, to ensure proper alignment between the vertical reflection waveguide 100 and the optical receiver 200, and thus to ensure a high power input to the optical receiver 200, the relative positions of the two must be adjusted. An auxiliary instrument (such as a power meter or power meter) is then used to detect the power input to the optical receiver 200. Only when the power value is high or reaches a preset threshold can the vertical reflection waveguide 100 and the optical receiver 200 be confirmed to be aligned and coupled. Because this method requires active components for alignment, it is referred to as active alignment. This method is time-consuming and costly. Summary of the Invention

[0005] Example embodiments of the present application provide new optical waveguide and alignment coupling schemes to reduce the cost and time of coupling alignment.

[0006] In a first aspect, the present application discloses an optical waveguide. The optical waveguide includes a substrate, a cladding layer, and a core layer.

[0007] The core layer is disposed within the cladding layer, which is disposed on the substrate. The substrate, cladding layer, and core layer form a groove opening toward a first direction, or the cladding layer and core layer form a groove opening toward the first direction, where the first direction is a direction away from the substrate toward the core layer or away from the cladding toward the substrate. The groove includes a first surface and a second surface arranged opposite each other. The first surface is a first inclined surface in the portion of the core layer, which is used to change the transmission direction of the signal light or continuous light. The second surface is a second inclined surface in the portion of the core layer, which is used to change the transmission direction of the auxiliary alignment light. The first inclined surface and the second inclined surface are reflective surfaces. The core layer includes a first core layer and a second core layer disposed on either side of the groove. The first core layer includes the first inclined surface, which is used to change the transmission path of the signal light or continuous light in the optical waveguide, so that the signal light or continuous light input into the optical waveguide along the first core layer is output along the second direction, or the signal light or continuous light input in the opposite direction of the second direction is transmitted along the first core layer. The second core layer includes the second inclined surface, which is used to change the transmission path of the auxiliary alignment light in the optical waveguide so that the auxiliary alignment light input into the optical waveguide along the second core layer is output along a third direction or the auxiliary alignment light input in the opposite direction of the third direction is transmitted along the second core layer, and the second direction and the third direction are toward the same side of the substrate.

[0008] In a possible implementation, the cladding includes a first cladding and a second cladding, the first cladding and the second cladding are adjacent to each other, and the core layer is disposed between the first cladding and the second cladding.

[0009] In a possible implementation, the first core layer and the second core layer are on the same plane. In this way, the manufacture of the optical waveguide is simple.

[0010] In a possible implementation, the third direction is parallel to the second direction. This design simplifies the design of the coupling alignment mark of the device that cooperates with the optical waveguide.

[0011] In a possible implementation, the third direction or the second direction is perpendicular to the substrate.

[0012] In a possible implementation, the first surface and the second surface are mirror-symmetrical.

[0013] In one possible implementation, the optical waveguide further includes a dustproof component, which is adjacent to the groove and is used to protect the groove from dust. For example, the dustproof component is a dust cover, which is provided on the substrate to seal the groove. In another example, the dustproof component is a filling material, which fills the groove and covers at least the first inclined surface and the second inclined surface, and the light refractive index of the filling material is lower than the light refractive index of the core layer. In another example, the dustproof component is a coating protective layer, which covers at least the first inclined surface and the second inclined surface. It should be understood that the dustproof component can improve the coupling efficiency of the optical waveguide. The above-mentioned dustproof solutions can be used in combination.

[0014] In one possible implementation, the optical waveguide further includes a photodetector, wherein the first inclined surface is a partially reflective and partially refracting surface. The photodetector is configured to receive light refracted by the first inclined surface and monitor the optical power of the signal light or continuous light. It should be understood that the photodetector can also be placed external to the optical waveguide and used in conjunction with the optical waveguide.

[0015] In a second aspect, an embodiment of the present application discloses an optical transmission system. The system includes an optical waveguide as disclosed in the first aspect or any specific implementation thereof and another optical waveguide. The other optical waveguide includes another substrate, another cladding, another core layer and an alignment mark. The other core layer is arranged in the other cladding, the other cladding is arranged on the other substrate, and the other optical waveguide includes a third surface, and the portion of the third surface on the other core layer is a third inclined surface. When the alignment mark of the other optical waveguide is on the transmission path of the auxiliary alignment light reflected by the second cross section of the optical waveguide, the third inclined surface is used to change the transmission direction of the signal light or continuous light output from the second direction so that the signal light or continuous light is output along the other core layer, or the third inclined surface is used to change the transmission direction of the signal light or continuous light transmitted along the other core layer so that the signal light or the continuous light is input into the optical waveguide in the opposite direction of the second direction and is transmitted along the first core layer after being reflected by the first inclined surface.

[0016] In a possible implementation, the alignment mark is located in the other cladding layer; or the alignment mark is located in the core layer.

[0017] In a possible implementation, the optical waveguide and the another optical waveguide are coupled in a close-fitting manner.

[0018] In a third aspect, an embodiment of the present application discloses a method for assisted alignment of a light beam. The method comprises several steps. First, the transmission path of the auxiliary alignment light formed by the first core layer and the first inclined surface of the optical waveguide is used to adjust the relative position of the light beam processing device and the optical waveguide. The optical waveguide comprises a substrate, a cladding and a core layer, and the substrate, the cladding and the core layer form an open groove, or the cladding and the core layer form an open groove. The groove comprises a first surface and a second surface set relative to each other, the first surface is a second inclined surface in the portion of the core layer, and the second inclined surface is used to change the transmission direction of the signal light or continuous light, the second surface is a first inclined surface in the portion of the core layer, the first inclined surface is used to change the transmission direction of the auxiliary alignment light, the first inclined surface and the second inclined surface are reflective surfaces, the core layer comprises a first core layer and a second core layer arranged on both sides of the groove, the first core layer comprises the first inclined surface, and the second core layer comprises the second inclined surface. The light beam processing device comprises an alignment mark. Secondly, when it is determined that the alignment mark is on the transmission path of the auxiliary alignment light, it is determined that the signal light or continuous light is transmitted by the optical waveguide to the beam processing device for processing by the optical beam processing device, or that the signal light or continuous light is transmitted by the beam processing device to the optical waveguide for beam deflection transmission by the optical waveguide.

[0019] In one possible implementation, the light beam processing device is an optical transmission waveguide. After transmission through the light beam processing device and the optical waveguide, the transmission direction of the signal light or the continuous light remains unchanged. In another possible implementation, the light beam processing device is an optical transmission waveguide. After transmission through the light beam processing device and the optical waveguide, the transmission direction of the signal light or the continuous light changes by 180 degrees.

[0020] In a possible implementation, the light beam processing device is a light receiving device or a light transmitting device.

[0021] By means of an auxiliary alignment light transmission path of independent signal light or continuous light, the optical waveguide disclosed in the present application can achieve fast and low-cost alignment coupling. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of a system including an existing vertical reflection waveguide;

[0023] Figure 2 A schematic structural diagram of a first optical waveguide provided in an embodiment of the present application;

[0024] Figure 3 A schematic structural diagram of a second optical waveguide provided in an embodiment of the present application;

[0025] Figure 4A schematic structural diagram of a third optical waveguide provided in an embodiment of the present application;

[0026] Figure 5 A schematic structural diagram of a fourth optical waveguide provided in an embodiment of the present application;

[0027] Figure 6 A schematic structural diagram of a first optical transmission system provided in an embodiment of the present application;

[0028] Figure 7 A schematic diagram of the structure of a second optical transmission system provided in an embodiment of the present application;

[0029] Figure 8 A schematic diagram of the alignment mark position calculation provided in an embodiment of the present application;

[0030] Figure 9 A schematic structural diagram of a third optical transmission system provided in an embodiment of the present application;

[0031] Figure 10 A schematic structural diagram of a fifth optical waveguide provided in an embodiment of the present application;

[0032] Figure 11 A schematic flow chart of the beam-assisted alignment method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to solve the problems existing in the prior art, the present application provides a new optical waveguide, system and beam-assisted alignment method.

[0034] Before describing the optical waveguide, system and beam-assisted alignment method in detail, the present application first provides some general descriptions. Unless otherwise specified, the following general descriptions apply to all embodiments of the present application.

[0035] The device form and business scenarios described in the embodiments of this application are intended to more clearly illustrate the technical solutions of the embodiments of the present invention and do not constitute a limitation on the technical solutions provided in the embodiments of this application. Persons skilled in the art will appreciate that, with the evolution of device form factors and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0036] The technical solution proposed in this application can be applied to optical communication systems. For example, data center networks, optical transmission networks, optical access networks, or data communication networks. Specifically, the technical solution proposed in this application can be used in any of the aforementioned networks, corresponding to the portion requiring light beam deflection and transmission. For example, it can be used in scenarios where two devices are connected. Another example is scenarios where two components within a device are connected. This application does not limit the length of the optical waveguide. For example, in the scenario of internal device interconnection mentioned above, the optical waveguide length can be 20 mm to 30 cm.

[0037] It should be noted that the terms "first", "second", etc. in this application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments described here can be implemented in an order not described in this application. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. Unless otherwise specified, the same or similar technical descriptions provided in the method embodiments can also be applied to the device embodiments. And vice versa.

[0038] Unless otherwise specified, the detailed description of certain technical features in one embodiment can also be used to explain the corresponding technical features mentioned in other embodiments. For example, examples of materials for optical waveguides in one embodiment can be applied to optical waveguides mentioned in other embodiments. Another example is the description of the position of alignment marks. In addition, to more clearly illustrate the relationship between components in different embodiments, this application uses the same or similar figure numbers to represent components with the same or similar functions in different embodiments.

[0039] Active alignment requires instruments such as power meters to determine the alignment of the optical waveguide and its associated components, which can be time-consuming and costly. To address this, the present application provides a new optical waveguide and beam alignment method. This new optical waveguide includes an auxiliary alignment optical path, enabling fast, efficient, and cost-effective beam alignment.

[0040] Figure 2 This is a schematic diagram of the structure of the first optical waveguide provided in the embodiment of the present application. Figure 2 As shown, the optical waveguide 300 includes a base layer, a core layer and a cladding layer (301, 302 and 303), and a groove 304 formed by the base layer, the core layer and the cladding layer. The core layer includes one or more optical paths, all of which are used for light beams. Specifically, the light beam includes signal light or continuous light, or auxiliary alignment light. Signal light refers to a light beam loaded with data. Continuous light is called Continuous Wave (CW) in English, which refers to a light beam without data loaded. The cladding layer covers the core layer, which can also be called a cladding layer or a cladding layer. Its refractive index is different from that of the core layer. The refractive index difference formed by the two can play the role of light being confined to the core layer for transmission. The base layer is a layer arranged on one side of the cladding layer, which can also be called a substrate, and is used to provide mechanical strength and physical support.

[0041] It should be noted that Figure 2 The optical waveguide does not distinguish the relative position relationship between the base layer, the core layer and the cladding. That is, the opening direction of the groove 304 can be away from the base layer toward the core layer or away from the cladding toward the base layer. For example, Figure 2The opening of the groove shown is opened on the base layer, and the bottom of the groove is the cladding. Figure 2 The opening of the groove shown is open on the cladding, and the bottom of the groove is the cladding or core layer. In other words, the three layers of the substrate, cladding and core layer form an open groove; or, the cladding and core layer form an open groove. This application does not limit this. For more examples, please refer to Figure 3-9 Example of .

[0042] like Figure 2 As shown, the groove 304 includes two oppositely arranged surfaces (one surface is 304a, and the surface opposite to the surface 304a is adjacent to the groove 304). Figure 2 The portion of the surface 304a in the core layer is called the first inclined surface ( Figure 2 The surface opposite to the surface 304a in the core layer is called the second inclined surface ( Figure 2 (not shown in the figure), wherein the first inclined surface 304a-a is used to change the transmission direction of the signal light or the continuous light. The second inclined surface is used to change the transmission direction of the auxiliary alignment light. The first inclined surface 304a-a and the second inclined surface are both reflective surfaces. Specifically, if the groove is filled with air, it is necessary to design the refractive index difference between the first core layer and the air so that the first inclined surface 304a-a and the second inclined surface can achieve light reflection. It should be understood that if the groove is filled with other materials, the refractive index of the other materials should be less than the refractive index of the core layer so that the refractive index difference between the two can achieve light reflection on the two inclined surfaces.

[0043] It should be noted that the auxiliary alignment light can be natural light, or the auxiliary alignment light can be white light. For a description of the auxiliary alignment light and the transmission optical path of the auxiliary alignment light, please refer to the following embodiments.

[0044] The core layer is divided into two parts by the groove. Specifically, the core layer includes a first core layer and a second core layer. The first core layer is used to transmit signal light or continuous light. The first core layer includes a first inclined surface 304a-a. The first inclined surface 304a-a is used to change the transmission path of the signal light or continuous light in the optical waveguide 300, so that the signal light or continuous light input into the optical waveguide 300 along the first core layer is output along the second direction or the signal light or continuous light input in the opposite direction of the second direction is transmitted along the first core layer. The second core layer is used to transmit auxiliary alignment light and includes a second inclined surface. The second inclined surface is used to change the transmission path of the auxiliary alignment light in the optical waveguide 300, so that the auxiliary alignment light input into the optical waveguide 300 along the second core layer is output along the third direction or the auxiliary alignment light input in the opposite direction of the third direction is transmitted along the second core layer. The second direction and the third direction are toward the same side of the substrate.

[0045] In order to more clearly describe the relationship between the second direction and the third direction, and the three layers of the optical waveguide, more device embodiments are provided below.

[0046] Figure 3 This is a schematic diagram of the structure of the second optical waveguide provided in the embodiment of the present application. It should be understood that Figure 3 Provided along Figure 2 The device cross-sectional view in the direction of AA' is shown. Specifically, Figure 3 The optical waveguide 300 shown includes base and cladding layers (301 and 303), core layers (302a and 302b), and grooves 304. It should be understood that Figure 3 In the illustrated example, the relative positions of the base layer and the cladding layer are not distinguished; specifically, the base layer may be located at the top and the cladding layer may be located below the base layer; or the base layer may be located at the bottom and the cladding layer may be located above the base layer. When the base layer is located at the bottom, the bottom surface of the groove 304 may be either the cladding layer or the base layer.

[0047] like Figure 3 As shown, the core layer includes a first core layer 302a and a second core layer 302b. The groove 304 includes two oppositely arranged surfaces, namely surface 304a and surface 304b. The portion of surface 304a on the first core layer 302a is called a first inclined surface 304a-a, and the portion of surface 304b on the second core layer is called a second inclined surface 304b-b. Specifically, the first inclined surface 304a-a is used to reflect the incident light incident from the left end face of the first core layer 302a, so that the incident light is directed to the left side of the first core layer 302a. Figure 3 Alternatively, based on the principle of optical path reversibility, the first inclined surface 304a-a can also reflect light that is transmitted in the opposite direction of the outgoing light, so that it is transmitted along the first core layer 302a and output from the left end face of the first core layer 302a. Similarly, the first inclined surface 304b-b is used to reflect light incident from the right end face of the second core layer 302b, so that it is transmitted along Figure 3 The auxiliary alignment light emission direction shown ( Figure 3 Alternatively, based on the principle of optical path reversibility, the second inclined surface 304b-b can also be used to reflect light transmitted in the opposite direction of the auxiliary alignment light, so that it is transmitted along the second core layer 302b and output from the right end surface of the second core layer 302b. Figure 3 The exit light direction and the auxiliary alignment light exit direction shown are both in the same direction, that is, perpendicular to the optical waveguide 300 and downward. It should be understood that in a specific application, Figure 3 The second and third directions shown do not have to be oriented perpendicular to the optical waveguide. This application only requires that the two directions are oriented toward the same side of the core layer. For example Figure 3 For more examples, see Figure 5-7 The examples in the accompanying drawings are not described in detail here.

[0048] It should be noted that during the manufacturing process, the cladding may be made in two steps. Specifically, the first cladding is coated on the base layer, and then one or more optical paths (constituting the core layer) are placed, and then another cladding is coated to completely cover the core layer. Therefore, the cladding in the present application may include a first cladding and a second cladding, and the first cladding and the second cladding are adjacent. The core layer is arranged between the first cladding and the second cladding. The first cladding and the second cladding may also be referred to as the upper cladding and the lower cladding, respectively. It should be understood that the cladding may also be integrally formed, and then a core layer is processed in the middle of the cladding through a special process to form a structure in which the same cladding fully wraps the core layer. For example: through a laser direct writing process. A single optical path can be used to transmit light of one or more wavelengths. It should be understood that in Figure 3 In the example shown in FIG, the two parts of the core layer are located at the same level. During the manufacturing process, the two parts can be manufactured in one step, which is relatively simple.

[0049] It should be understood that in this embodiment, the surface 304a and the surface 304b are mirror-symmetrical, so that the direction of the emitted light and the direction of the auxiliary alignment light are parallel, thereby achieving the calibration function relatively simply.

[0050] It should be understood that in this embodiment, the first inclined surface 304a-a and the second inclined surface 304b-b are both fully reflective surfaces. In practical applications, these two inclined surfaces can also be partially reflective and partially refracting surfaces. Figure 5 The description is not repeated here.

[0051] When the optical waveguide 300 is coupled and aligned with another device (such as another optical waveguide, an optical transmitting device or an optical receiving device), the optical waveguide 300 uses the second inclined surface 304b-b to transmit auxiliary alignment light, thereby performing auxiliary alignment to achieve fast and low-cost coupling alignment.

[0052] It should be understood that the coupling of two devices mentioned in this application refers to the transmission of signal light or continuous light from one device to another device directly or indirectly. One of the two devices refers to the optical waveguide of this application, and the other device refers to another device coupled to the optical waveguide. Specifically, the other device can be another optical waveguide, an optical transmitting device, or an optical receiving device. For detailed description, see Figure 6-7 and 9, which will not be elaborated here.

[0053] Optionally, Figure 3 The two directions described may be parallel to each other, so that the position of the alignment mark of the device coupled to the optical waveguide can be determined more easily.

[0054] Figure 4 This is a schematic diagram of the structure of the third optical waveguide provided in the embodiment of the present application. It should be understood that similar Figure 3 , Figure 4 A cross-sectional view of the optical waveguide is also provided. Figure 4 and Figure 1 A stereogram example, a person skilled in the art can know without creative work Figure 4 The corresponding device stereogram. Figure 4 As shown, the optical waveguide 400 includes a base layer 403, a cladding layer 401 and a core layer (302a and 402b), and a groove 404 formed by these three layers. Specifically, the functions of the base layer 403, the cladding layer 401 and the core layer can be seen in Figure 2-3 The description of the corresponding objects shown in the figure will not be repeated here. Figure 2-3 Compared with the device shown in FIG. 1 , the optical waveguide 400 provided in this embodiment has the following main differences.

[0055] First, the directions of incidence or emission of the two light beams (i.e., (1) signal light or continuous light and (2) auxiliary alignment light) are located above the core layer. For example, the directions of incidence of the two light beams from the base layer can also be described as being toward the same side of the base layer 403. Figure 4 As shown, signal light or continuous light enters the optical waveguide 400 from the upper side of the optical waveguide 400 through the base layer 403, reflects off the first cross section 404a-a, transmits through the core layer 302a, and is output from the left end face of the core layer 302a. Similarly, auxiliary alignment light enters the optical waveguide 400 from the upper layer through the base layer 403, reflects off the second cross section 404b-b, and is output from the core layer 402b. Based on the principle of reversible optical paths, the reverse direction described above is also possible.

[0056] In practical applications, signal light or continuous light may come from Figure 4 The auxiliary alignment light is incident along the vertical direction. It should be understood that in this application scenario, the relationship between the two beams can be described as being above the core layer. Or, if Figure 4 The opposite direction of the incident light direction is shown as the first direction, and the vertical downward direction of the auxiliary alignment light is shown as the second direction. The above application scenario can also be described as the opposite direction of the first direction and the second direction facing the same side of the base layer.

[0057] Secondly, the core layers 302a and 402b are not located at the same level. That is, the core layer 302a for transmitting signal light or continuous light and the core layer 402b for transmitting auxiliary alignment light are made separately to obtain Figure 4 Two core layers at different levels are shown.

[0058] Third, the shape of the groove is different. Correspondingly, the directions of the signal light or continuous light and the auxiliary alignment light input or output of the optical waveguide 400 are different. Taking the example that the incident light and the auxiliary alignment light are both input from the side of the core layer, then in this embodiment, the input directions of the two light beams are both toward the upper side of the base layer. Differently, Figure 3 In the example shown, the output directions of both light beams are toward the underside of the substrate.

[0059] exist Figure 4 In the example shown, by providing a transmission path for auxiliary alignment light, the optical waveguide 400 can be determined to have completed coupling alignment with the device when the auxiliary alignment light path is used to see the alignment mark of the device coupled to the optical waveguide 400. This coupling alignment method is fast and low-cost.

[0060] Figure 5 This is a schematic diagram of the structure of the fourth optical waveguide provided in the embodiment of the present application. It should be understood that similar Figure 3 , Figure 5 Also provided is a cross-sectional view of an optical waveguide. Figure 5 and Figure 1 A stereogram example, a person skilled in the art can know without creative work Figure 5 The corresponding device stereogram. Figure 5 As shown, the optical waveguide 500 includes a base layer and a cladding layer (301 and 303) and a core layer (302a and 302b), and a groove 504 formed by these three layers. Specifically, the functions of the base layer, cladding layer and core layer can be seen in Figure 2-3 The description of the corresponding objects shown in the figure will not be repeated here. Figure 2-3 Compared with the device shown in FIG. 1 , the optical waveguide 500 provided in this embodiment has the following main differences.

[0061] First, the inclination of the two opposing surfaces of the groove ensures that the directions of the outgoing light and the auxiliary alignment light are not perpendicular to the substrate or cladding. This design can meet the needs of different application scenarios. For example, if the device receiving the outgoing light is limited in length, the alignment mark needs to be designed close to the light receiving point. In another example, the device receiving the outgoing light only supports tilted reception.

[0062] Secondly, the cross section 504a-a is designed to be partially reflective and partially refracting. Figure 5As shown, cross section 504a-a not only reflects most of the incident light in the direction of the outgoing light shown in the figure, but also refracts a small portion of the incident light in the direction of the refracted light shown in the figure. The refracted light can be used in conjunction with an optical monitoring device (such as a conventional PD or APD, etc.). Because the percentage of the refracted light intensity to the entire incident light can be pre-set, using an optical monitoring device to monitor the power of the refracted light can provide input for many device control and judgment information, such as: incident light power, coupled optical power intensity, etc., which are used to monitor the power of the signal light or light beam. This can determine the coupling efficiency. It should be understood that this optical monitoring device can be set in the groove 504; alternatively, this optical monitoring device can be placed separately and used in conjunction with the optical waveguide 500 to form a system.

[0063] exist Figure 5 In the example shown, the optical waveguide 500 utilizes the transmission path of the auxiliary alignment light to achieve fast and low-cost coupling alignment. Optionally, the optical waveguide 500 can also monitor the signal light or continuous light by refracting part of the signal light or continuous light.

[0064] Figure 6 This is a schematic diagram of the structure of the first optical transmission system provided in the embodiment of the present application. Figure 6 As shown, the optical transmission system includes an optical waveguide 300 and an optical waveguide 600. The optical waveguide 300 is Figure 2 It should be understood that the optical waveguide 300 can also be replaced by Figure 4 or 5, or other variations described in this application. This application does not limit this. The optical waveguide 600 includes a core layer, a cladding layer, and a base layer ( Figure 6 The three layers of the optical waveguide 600 form an inclined surface on one end face for deflecting the light beam (hereinafter referred to as the third section). The alignment mark 601 is used to achieve coupling alignment. Figure 6 As shown, when alignment mark 601 of optical waveguide 600 can be identified through the auxiliary alignment transmission optical path, it can be determined that the signal light output by optical waveguide 300 can be transmitted in the core layer of optical waveguide 600 after reflection from the third cross section, and vice versa. In other words, optical waveguide 300 and optical waveguide 600 can form an optical transmission system to complete the transmission of signal light. It should be understood that the signal light in this embodiment can also be replaced by continuous light.

[0065] like Figure 6As shown, the auxiliary alignment light transmission path can be used to see whether the auxiliary alignment mark can be observed with the help of natural light to determine whether the two devices are aligned. Alternatively, light emitted by a white light source can be used. For example, a white light source can be placed below the auxiliary alignment mark of the optical waveguide 600, and then the auxiliary alignment light can be observed through the auxiliary alignment light transmission path. Alternatively, the auxiliary alignment light can be observed at the observation port (at the Figure 6 A light beam (located on the right end face of optical waveguide 300) is actively transmitted to assist in alignment. This light beam is reflected off optical waveguide 600 to determine whether the auxiliary alignment mark is observed. This method of actively transmitting a light beam offers higher accuracy. The method can be selected based on specific needs and is not limited in this application.

[0066] It should be noted that Figure 6-9 Test diagrams of an optical waveguide are provided. To clearly describe the corresponding embodiments, the positions of the core layer and / or the groove in the optical waveguide are provided with dotted lines in these drawings.

[0067] It should be noted that, in this embodiment, there is a certain distance between the two waveguides. In practical applications, the two waveguides can be directly bonded to improve coupling efficiency and prevent the optical path from being contaminated.

[0068] It should be understood that in this embodiment, the alignment mark 601 is set on the surface layer (base layer or cladding layer) of the optical waveguide 600. In actual application, it can also be set on the core layer, see Figure 7 The embodiments shown are not described in detail here.

[0069] Figure 7 This is a schematic diagram of the structure of the second optical transmission system provided in the embodiment of the present application. Figure 7 As shown, the optical transmission system includes an optical waveguide 300 and an optical waveguide 700. The optical waveguide 300 is Figure 2 It should be understood that the optical waveguide 300 can also be replaced by Figure 4 or 5, or other variations described in this application. This application does not limit this. The optical waveguide 700 includes a core layer, a cladding layer, and a base layer ( Figure 7 The three layers of the optical waveguide 700 form a groove, wherein one side of the groove is used to deflect the inclined surface of the light beam (hereinafter referred to as the fourth section). The alignment mark 701 is set in the core layer to achieve coupling alignment. Figure 7As shown, when alignment mark 701 of optical waveguide 700 can be identified through the auxiliary alignment transmission optical path of optical waveguide 300, it can be determined that the signal light output by optical waveguide 300 can be transmitted in the core layer of optical waveguide 700 after being reflected by the fourth cross section; and vice versa. In other words, optical waveguide 300 and optical waveguide 700 can form an optical transmission system to complete the transmission of signal light.

[0070] It should be understood that the signal light in this embodiment can also be replaced by continuous light. The position of the alignment mark 701 can also be set at other positions, such as Figure 6 The embodiment shown.

[0071] In actual design, the position selection of the alignment mark is related to multiple parameters of the two coupled devices. Figure 6 and Figure 7 In the groove of the optical waveguide 300, the inclination angle of the two cross sections for reflecting the light beam, the distance between the cross section of the groove in the core layer and the bottom of the groove, etc. In addition, the coupling distance between the two devices may also need to be taken into account in the position setting of the alignment mark. Figure 8 To illustrate the design of the alignment mark position.

[0072] Figure 8 This is a schematic diagram of the alignment mark position calculation provided in the embodiment of the present application. Specifically, Figure 8 Some parameters related to the position design of the alignment marks of the optical waveguide 300 and the optical waveguide 700 are given. It should be understood that Figure 8 Not all component examples are given. Specifically, H2 and H1 represent the heights of the first and second core layers from the bottom, respectively; W1 represents the distance between the two reflective surfaces; angles a and b represent the angles between the emission directions of the two light beams ((1) auxiliary alignment light and (2) signal light or continuous light) and the vertical direction, respectively; D represents the distance between the reflective surface of the optical waveguide 700 and the alignment mark; and H3 represents the spacing between the two waveguides.

[0073] Using the above parameters, it can be found that D = W1 + (H2 + H3) * tan (b) - (H1 + H3) * tan (a).

[0074] With the help of this formula, after obtaining the corresponding parameters, the position of the alignment mark can be known to design and produce the corresponding optical waveguide 700. Alternatively, after the optical waveguide 700 has been designed (i.e., D is known), the parameters of the optical waveguide 300 can be made to meet the above formula during design and production to achieve Figure 8 The optical transmission system shown.

[0075] It should be understood that if the alignment mark is not located inside the optical waveguide or the structures of the two waveguides are different, Figure 8While the examples shown are slightly different, the above formulas still apply. Some parameters may require modification. For example, if the signal light or continuous light propagates parallel to the auxiliary alignment light, then D = W1. Alternatively, if the alignment mark is designed on the surface of the waveguide, then D measures the distance between the signal light or continuous light and the alignment mark at the point where it enters or exits the waveguide. Alternatively, the angle between the two beams can be calculated using their angle relative to the horizontal.

[0076] Figure 9 This is a schematic diagram of the structure of the third optical transmission system provided in the embodiment of the present application. Figure 9 As shown, the optical transmission system includes an optical waveguide 300 and an optical receiving or transmitting device 800. The optical waveguide 300 is Figure 2 It should be understood that the optical waveguide 300 can also be replaced by Figure 4 or 5, or the optical waveguide or other deformation described in this application. This application does not limit this. The optical receiving or transmitting device 800 includes an optical transmitting component or an optical receiving component and an alignment mark 801. Figure 9 As shown, when the alignment mark 801 of the optical receiving or transmitting device 800 can be identified through the auxiliary alignment transmission optical path of the optical waveguide 300, it can be determined that the signal light output by the optical waveguide 300 can be received by the optical receiving or transmitting device 800, or that the signal light transmitted by the optical receiving or transmitting device 800 can be transmitted through the optical waveguide 300 and output by the core layer. It should be understood that the aforementioned alignment mark can be identified with the assistance of an image recognition device or directly observed through the transmission optical path of the auxiliary alignment light.

[0077] It should be understood that the alignment marks of the optical receiving or transmitting device 800 can be in accordance with Figure 9 The alignment mark position described in the embodiment of the present invention may be designed, or some external marks already existing on the optical receiving or transmitting device 800 may be used to achieve alignment. Figure 9 The relevant design principle is to design the parameters of the light deflection waveguide that matches the light transmitting device or the light receiving device by numbering the surface of the light transmitting device or the light receiving device. This application does not limit this.

[0078] Figure 10 This is a schematic diagram of the structure of the fifth optical waveguide provided in the embodiment of the present application. Figure 10 As shown, the optical waveguide 900 includes Figure 2 In addition to the components of the optical waveguide 300 (attached Figure 9 No reference numerals are provided for corresponding components. Figure 2-3 ), and also includes a dustproof component. The dustproof component is used to prevent the inclined surface of the reflected or refracted light beam from being contaminated by dust or water, etc., effectively ensuring the coupling efficiency. In a specific design, the dustproof component can be a cover plate, such as Figure 10As shown in 901, the cover plate covers the opening of the groove. In another specific design, the dustproof component can be a coating protective layer, such as Figure 10 As shown in part 902, the coating protective layer at least covers the oblique portion of the reflected or refracted light beam. The coating protective layer can be called a protective layer or a coating layer, etc., which is not limited in this application. In addition, the coating can also accurately control the reflectivity / refractive index to improve the reflection efficiency or refraction efficiency. In another design, the dustproof component is a filling material that at least fills and covers the oblique portion of the reflected or refracted light beam. It should be noted that the light refractive index of the filling material is less than the light refractive index of the core layer to achieve light reflection.

[0079] It should be understood that the above-mentioned various design methods can also be combined to provide protection. Figure 10 As shown, a cover plate 901 and a coating layer 902 can be provided at the same time. The coating layer can be matched with Figure 5 The embodiment including the PD is used to achieve refraction of the monitoring wavelength in the signal light or continuous light wavelength, and reflection of the other parts of the signal light or continuous light wavelength, thereby achieving efficient monitoring. This application does not limit this.

[0080] Figure 10 The optical waveguide 900 shown can not only achieve rapid coupling alignment, but also improve the reliability of the optical waveguide 900 and ensure performance.

[0081] It should be understood that the optical waveguide material in the above device embodiment can be a polymer waveguide such as quartz, silicon, or silicon nitride. Alternatively, the optical waveguide material can also be glass, silicon dioxide, silicon nitride, silicon oxynitride, and / or lithium niobate, etc. This application does not limit this.

[0082] Figure 11 The flowchart of the beam-assisted alignment method provided in the embodiment of the present application is shown in FIG. Specifically, the beam-assisted alignment method includes the following two steps.

[0083] In section 1501, the relative positions of the light beam processing device and the light beam waveguide are adjusted using the transmission path of the auxiliary alignment light formed by the first core layer and the first inclined surface of the light beam waveguide. The light beam waveguide comprises a substrate, a cladding layer, and a core layer. The substrate, the cladding layer, and the core layer form an open groove. The groove comprises a first surface and a second surface arranged opposite each other. The first surface, in the portion of the core layer, serves as the second inclined surface. The second inclined surface is used to transmit signal light or continuous light. The second surface, in the portion of the core layer, serves as the first inclined surface. The first inclined surface is used to transmit the auxiliary alignment light. The first and second inclined surfaces are reflective surfaces. The core layer comprises a first core layer and a second core layer disposed on either side of the groove. The first core layer comprises the first inclined surface, and the second core layer comprises the second inclined surface. The light beam processing device comprises an alignment mark.

[0084] Specifically, the optical waveguide can be Figure 2-3 、 Figure 4-5 or Figure 9 Any of the devices shown. This embodiment does not limit this.

[0085] In section 1502, when it is determined that the alignment mark is on the transmission path of the auxiliary alignment light, it is determined that the signal light or continuous light is transmitted by the optical waveguide to the beam processing device for processing by the optical waveguide, or that the signal light or continuous light is transmitted by the beam processing device to the optical waveguide for beam deflection transmission by the optical waveguide.

[0086] Specifically, it can be determined that the alignment mark is observed through the transmission path of the auxiliary alignment light, thereby determining that the coupling alignment of the two devices has been completed (ie, effective transmission of the light beam between the two devices can be completed).

[0087] In a specific implementation, the light beam processing device is an optical transmission waveguide. After being transmitted through the light beam processing device and the optical waveguide, the transmission direction of the signal light or the continuous light does not change. For example, Figure 6 The transmission path of the signal light is shown.

[0088] In another specific implementation, the beam processing device is an optical transmission waveguide. After being transmitted through the beam processing device and the optical waveguide, the transmission direction of the signal light or the continuous light changes by 180 degrees. For example, Figure 7 The transmission path of the signal light is shown.

[0089] In yet another specific implementation, the light beam processing device is a light receiving device or a light transmitting device.

[0090] Finally, it should be noted that the above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included within the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. An optical transmission system, characterized in that The system includes an optical waveguide comprising a substrate, a cladding layer, and a core layer, wherein: The core layer is arranged in the cladding layer, and the cladding layer is arranged on the substrate; The substrate, the cladding layer, and the core layer form a groove opening toward a first direction, or the cladding layer and the core layer form a groove opening toward the first direction, wherein the first direction is a direction away from the substrate toward the core layer or a direction away from the cladding toward the substrate; The groove includes a first surface and a second surface opposite to each other, wherein the first surface is a first inclined surface at the core layer, and the first inclined surface is used to change the transmission direction of the signal light or the continuous light, and the second surface is a second inclined surface at the core layer, and the second inclined surface is used to change the transmission direction of the auxiliary alignment light, and the first inclined surface and the second inclined surface are reflective surfaces; The core layer includes a first core layer and a second core layer arranged on both sides of the groove, wherein: The first core layer includes the first inclined surface, and the first inclined surface is used to change the transmission path of the signal light or the continuous light in the optical waveguide, so that the signal light or the continuous light input into the optical waveguide along the first core layer is output along the second direction or the signal light or the continuous light input in the opposite direction of the second direction is transmitted along the first core layer; The second core layer includes a second inclined surface, and the second inclined surface is used to change a transmission path of the auxiliary alignment light in the optical waveguide, so that the auxiliary alignment light input into the optical waveguide along the second core layer is output along a third direction or the auxiliary alignment light input in a direction opposite to the third direction is transmitted along the second core layer, and the second direction and the third direction are toward the same side of the substrate; The optical transmission system further includes another optical waveguide, wherein the another optical waveguide includes another substrate, another cladding layer, another core layer, and an alignment mark, wherein: The other core layer is arranged in the other cladding layer, the other cladding layer is arranged on the other substrate, the other optical waveguide includes a third surface, and a portion of the third surface on the other core layer is a third inclined surface; When the alignment mark of the other optical waveguide is on the transmission path of the auxiliary alignment light reflected by the second cross-section of the optical waveguide, the third inclined surface is used to change the transmission direction of the signal light or the continuous light output from the second direction so that the signal light or the continuous light is output along the other core layer, or the third inclined surface is used to change the transmission direction of the signal light or the continuous light transmitted along the other core layer so that the signal light or the continuous light is input into the optical waveguide in the opposite direction of the second direction and is transmitted along the first core layer after being reflected by the first inclined surface; The arrangement position of the alignment mark satisfies: D=W1+(H2+H3)*tan(b)-(H1+H3)*tan(a); H2 is the height of the first core layer from the bottom, H1 is the height of the second core layer from the bottom; W1 is the distance between the first inclined surface and the second inclined surface; Angle a is the angle between the emitting direction of the auxiliary alignment light and the vertical direction; Angle b is the angle between the emitting direction of the signal light or continuous light and the vertical direction; D is the distance between the third inclined surface of the other optical waveguide and the alignment mark; H3 is the distance from the bottom surface of the optical waveguide to the core layer of the other optical waveguide.

2. The optical transmission system according to claim 1, wherein The cladding layer includes a first cladding layer and a second cladding layer, the first cladding layer and the second cladding layer are adjacent to each other, and the core layer is disposed between the first cladding layer and the second cladding layer.

3. The optical transmission system according to claim 1 or 2, wherein: The first core layer and the second core layer are on the same plane.

4. The optical transmission system according to any one of claims 1 to 3, wherein: The third direction is parallel to the second direction.

5. The optical transmission system according to any one of claims 1 to 4, wherein: The third direction or the second direction is perpendicular to the substrate.

6. The optical transmission system according to any one of claims 1 to 5, wherein: The first surface and the second surface are mirror-symmetrical.

7. The optical transmission system according to any one of claims 1 to 6, wherein: The optical waveguide further includes a dustproof component, which is adjacent to the groove and is used to prevent dust from entering the groove.

8. The optical transmission system according to claim 7, wherein: The dustproof component is a dustproof cover, which is arranged on the substrate to seal the groove.

9. The optical transmission system according to claim 7, wherein: The dustproof component is a filling material, which fills the groove and covers at least the first inclined surface and the second inclined surface. The light refractive index of the filling material is lower than the light refractive index of the core layer.

10. The optical transmission system according to claim 7, wherein: The dustproof component is a coating protection layer, and the coating protection layer at least covers the first inclined surface and the second inclined surface.

11. The optical transmission system according to any one of claims 1 to 10, wherein: The material of the optical waveguide is polymer, glass or silicon.

12. The optical transmission system according to any one of claims 1 to 11, wherein: The length of the optical waveguide is between 20 mm and 30 cm.

13. The optical transmission system according to any one of claims 1 to 12, wherein: The alignment mark is located in the other cladding layer; or, the alignment mark is located in the core layer.

14. The optical transmission system according to any one of claims 1 to 13, wherein: The optical waveguide and the another optical waveguide are coupled in a close-fitting manner.

15. A beam-assisted alignment method, characterized in that: The method comprises: The relative position of the light beam processing device and the optical waveguide is adjusted by utilizing the transmission path of the auxiliary alignment light formed by the first core layer and the first inclined surface of the optical waveguide, wherein: The optical waveguide includes a substrate, a cladding layer, and a core layer, wherein the substrate, the cladding layer, and the core layer form an open groove, or the cladding layer and the core layer form an open groove; The groove includes a first surface and a second surface set opposite to each other, the first surface is a second inclined surface in the portion of the core layer, and the second inclined surface is used to change the transmission direction of the signal light or the continuous light, the second surface is a first inclined surface in the portion of the core layer, and the first inclined surface is used to change the transmission direction of the auxiliary alignment light, the first inclined surface and the second inclined surface are reflective surfaces, the core layer includes a first core layer and a second core layer arranged on both sides of the groove, the first core layer includes the first inclined surface, and the second core layer includes the second inclined surface; The beam processing device includes another optical waveguide, the other optical waveguide including another substrate, another cladding, another core layer, and an alignment mark; the other core layer is disposed in the other cladding, the other cladding is disposed on the other substrate, the other optical waveguide includes a third surface, and a portion of the third surface on the other core layer is a third inclined surface; When it is determined that the alignment mark is on the transmission path of the auxiliary alignment light, determining that the signal light or the continuous light is transmitted by the optical waveguide to the beam processing device for processing by the optical waveguide, or that the signal light or the continuous light is transmitted by the beam processing device to the optical waveguide for beam deflection transmission by the optical waveguide; The arrangement position of the alignment mark satisfies: D=W1+(H2+H3)*tan(b)-(H1+H3)*tan(a); H2 is the height of the first core layer from the bottom, H1 is the height of the second core layer from the bottom; W1 is the distance between the first inclined surface and the second inclined surface; Angle a is the angle between the emitting direction of the auxiliary alignment light and the vertical direction; Angle b is the angle between the emitting direction of the signal light or continuous light and the vertical direction; D is the distance between the third inclined surface of the other optical waveguide and the alignment mark; H3 is the distance from the bottom surface of the optical waveguide to the core layer of the other optical waveguide.

16. The method according to claim 15, wherein The light beam processing device is an optical transmission waveguide, wherein: after being transmitted through the light beam processing device and the optical waveguide, the transmission direction of the signal light or the continuous light remains unchanged.

17. The method according to claim 15, wherein The beam processing device is an optical transmission waveguide, wherein: after being transmitted through the beam processing device and the optical waveguide, the transmission direction of the signal light or the continuous light changes by 180 degrees.

18. The method according to any one of claims 15 to 17, wherein: The light beam processing device is a light receiving device or a light sending device.

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