Optical waveguide connection structure

Abstract

To provide an optical waveguide connection structure capable of achieving highly efficient optical coupling with a simple configuration, an optical waveguide connection device, and an optical waveguide connection method.SOLUTION: The optical waveguide connection structure includes: an optical fiber unit that has an optical fiber and an optical fiber holding member for holding the optical fiber; an optical input part provided at the end of an optical waveguide; and an optical circuit board that has a ring guide provided to surround the optical input part. The optical fiber unit is connected to the optical input part via glue located in the inner area of the guide.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an optical waveguide connection structure, an optical waveguide connection device, and an optical waveguide connection method. [Background technology]

[0002] In recent years, the use of light has been considered in fields such as high-speed and large-capacity communication, sensing, etc. In particular, a technology called "silicon photonics" has attracted attention, in which fine optical circuits with optical control functions are formed on a silicon substrate using the Complementary Metal Oxide Semiconductor (CMOS) process, similar to semiconductor electronic circuits.

[0003] The microcircuits on optical circuit boards formed using silicon photonics technology contain optical input / output sections, optical modulators, etc. These are connected by fine thin-line waveguides on the submicron order. In addition, in order to connect external transmission bodies such as optical fibers to the thin-line waveguides with high precision (fiber-to-chip connection), various optical interfaces are being actively developed.

[0004] Patent Document 1 discloses a technique relating to fiber-to-chip connection that can suppress the influence of misalignment caused by cure shrinkage, thermal expansion, and the like, and achieve highly efficient optical coupling.

[0005] In the optical module disclosed in Patent Document 1, an optical fiber is fixed at a certain angle to an optical wiring board so as to obtain optical coupling between an optical input section (diffraction grating) on ​​the optical wiring board and the tip of the optical fiber.

[0006] In the technology disclosed in Patent Document 1, specially shaped members (first ferrule, second ferrule, etc.) are used on the optical fiber side to suppress misalignment of the optical fiber with respect to the diffraction grating. In addition, in the technology disclosed in Patent Document 1, a stopper called a bank is provided on the optical wiring board to uniformly form a fillet of the adhesive. This makes it possible to suppress misalignment of the optical fiber due to the hardening shrinkage of the adhesive. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2019-78813 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, the technology disclosed in Patent Document 1 requires components such as a first ferrule, a second ferrule, and a stopper to suppress misalignment between the optical fiber to be optically coupled and the optical input section, which results in a complex structure of the optical wiring board, which requires time-consuming work when assembling the optical wiring board, and which may further reduce the reliability of the optical wiring board.

[0009] Non-limiting examples of the present disclosure contribute to providing an optical waveguide connection structure, an optical waveguide connection device, and an optical waveguide connection method that achieve highly efficient optical coupling with a simple configuration. [Means for solving the problem]

[0010] An optical waveguide connection structure according to one embodiment of the present disclosure comprises an optical fiber unit having an optical fiber and an optical fiber holding member that holds the optical fiber, an optical input portion provided at an end of the optical waveguide, and an optical circuit board having an annular guide provided to surround the optical input portion, and the optical fiber unit is connected to the optical input portion via an adhesive present in an inner region of the guide.

[0011] An optical waveguide connection device according to one embodiment of the present disclosure includes a sample stage for placing an optical circuit board, an adhesive supplying unit that supplies uncured adhesive to an inner area of ​​a ring-shaped guide that is arranged to surround an optical input unit provided on the optical circuit board, a light receiving unit that receives light emitted from the optical circuit board, an optical fiber alignment mechanism that aligns an optical fiber with respect to the optical input unit so that the light intensity received by the light receiving unit is maximized while the uncured adhesive is supplied to the inner area of ​​the guide, an adhesive curing unit that cures the uncured adhesive while the optical fiber is aligned with the optical input unit, and an adhesive curing unit adjustment mechanism that adjusts the angle and position of the adhesive curing unit when the uncured adhesive hardens.

[0012] An optical waveguide connection method according to one embodiment of the present disclosure includes an uncured adhesive supplying step of supplying uncured adhesive to an inner area of ​​a ring-shaped guide that is arranged to surround an optical input section provided on an optical circuit board; an alignment step of aligning an optical fiber with respect to the optical input section while the uncured adhesive is supplied to the inner area of ​​the guide so that the intensity of light detected by a light receiving section that receives light emitted from the optical circuit board is maximized; an adhesive curing step of curing the uncured adhesive while the optical fiber is aligned with the optical input section; and an adhesive curing section adjustment step of adjusting the angle and position of the adhesive curing section that cures the uncured adhesive in the adhesive curing step. Effect of the Invention

[0013] According to an embodiment of the present disclosure, it is possible to construct an optical waveguide connection structure, an optical waveguide connection device, and an optical waveguide connection method that realize highly efficient optical coupling with a simple configuration.

[0014] Further advantages and benefits of an embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some of the embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features. [Brief description of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view taken along the XZ plane of an optical waveguide connection structure 100 according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a plan view of the optical waveguide connection structure 100 shown in FIG. 1 , excluding the optical fiber unit 3, as viewed from above. [Diagram 3] FIG. 1 is a diagram showing a configuration example of an optical waveguide connection device D1 according to an embodiment of the present disclosure. [Figure 4] A flowchart for explaining an optical waveguide connection method using the connection device D1. [Diagram 5] 1 is a schematic top view illustrating an optical waveguide connection method according to an embodiment of the present disclosure; [Figure 6A] FIG. 1 is a diagram for explaining an adhesive curing portion adjustment step; [Figure 6B] FIG. 1 is a diagram for explaining an adhesive curing portion adjustment step; [Figure 6C] FIG. 1 is a diagram for explaining an adhesive curing portion adjustment step; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] A preferred embodiment of the present disclosure will be described in detail below with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functions are denoted by the same reference numerals to avoid repetitive description. In the following drawings, the shapes, thicknesses, lengths, etc. of the components shown in each drawing may differ from the shapes, thicknesses, lengths, etc. of the actual components due to the creation of the drawings. Furthermore, the materials of each component are not limited to those described in this embodiment.

[0017] In FIG. 1 and subsequent figures, the X-axis direction, the Y-axis direction, and the Z-axis direction respectively represent directions parallel to the X-axis, the Y-axis, and the Z-axis. The X-axis direction and the Y-axis direction are mutually orthogonal. The X-axis direction and the Z-axis direction are mutually orthogonal. The Y-axis direction and the Z-axis direction are mutually orthogonal. The XY plane represents a virtual plane parallel to the X-axis direction and the Y-axis direction. The XZ plane represents a virtual plane parallel to the X-axis direction and the Z-axis direction. The YZ plane represents a virtual plane parallel to the Y-axis direction and the Z-axis direction. In addition, the direction indicated by the arrow in the X-axis direction is the positive X-axis direction, and the opposite direction to the said direction is the negative X-axis direction. In the Y-axis direction, the direction indicated by the arrow is the positive Y-axis direction, and the opposite direction to the said direction is the negative Y-axis direction. In the Z-axis direction, the direction indicated by the arrow is the positive Z-axis direction, and the opposite direction to the said direction is the negative Z-axis direction. The Z-axis direction is, for example, equal to the vertical direction, the stacking direction, or the up-down direction, and the X-axis direction and the Y-axis direction are, for example, equal to the horizontal direction or the left-right direction.

[0018] [Embodiment Mode] First, an optical waveguide connection structure 100 according to an embodiment of the present disclosure will be described with reference to Figures 1 and 2. Figure 1 is a cross-sectional view along the XZ plane of the optical waveguide connection structure 100 according to an embodiment of the present disclosure, and Figure 2 is a plan view from above of the optical waveguide connection structure 100 shown in Figure 1, excluding the optical fiber unit 3.

[0019] <Optical waveguide connection structure 100> As shown in FIG. 1, the optical waveguide connection structure 100 includes an optical circuit board 1, an optical fiber unit 3, and an adhesive 5.

[0020] [Optical circuit board 1] The optical circuit board 1 includes an optical waveguide 101 , an optical input portion 102 , and a guide 2 .

[0021] [Optical waveguide 101] The optical waveguide 101 is a sheet-like or plate-like member for transmitting light from an optical input section 102 to an optical output section (not shown).

[0022] [Optical input section 102] The optical input section 102 is a grating coupler (diffraction grating type optical coupler) or the like.

[0023] [Guide 2] The guide 2 defines a mounting area for the optical fiber unit 3, and also functions as a stopper that prevents uncured adhesive supplied to the inner area of ​​the guide 2 from flowing out to the outside of the guide 2.

[0024] The shape of the guide 2 is, for example, an equilateral triangle in a plan view. The guide 2 is disposed on the surface of the optical circuit-board 1 in the positive Z-axis direction so as to surround the periphery of the optical input section 102. The optical input section 102 is disposed at a position overlapping with the center of gravity CG of the guide 2.

[0025] The dimensions of the guide 2 are set appropriately according to the dimensions of the optical fiber unit 3. Specifically, for example, when the optical fiber unit 3 is a cylinder with a diameter D of 0.5 [mm] to 5 [mm] and a height H of 0.5 [mm] to 10 [mm] as shown in Fig. 1, the dimensions of the guide 2 are set as follows. (Guide 2 dimensions) Length l of each side 2a of the guide 2: 0.5√3[mm]~5√3[mm] Width w of each side 2a of the guide 2: 50 [μm] to 1000 [μm] Height h of each side 2a of the guide 2: 50 [μm] to 100 [μm]

[0026] The guide 2 is manufactured by die-casting a metal, an acrylic resin, an epoxy resin, an acrylic epoxy resin, a silicon resin, or the like.

[0027] The manufacturing method of the guide 2 is not limited to this, and the guide 2 may be constructed, for example, by combining multiple plate-shaped members to surround the optical input section 102 and arranging them in a regular polygon shape on the surface of the optical circuit board 1 in the positive Z-axis direction.

[0028] The optical waveguide 101, the optical input portion 102 and the guide 2 are formed by, for example, patterning using photolithography, using a silicon layer on a silicon oxide film.

[0029] [Optical fiber unit 3] The optical fiber unit 3 is a unit for inputting light into the optical circuit board 1. The optical fiber unit 3 is fixed to the optical circuit board 1 via an adhesive 5.

[0030] In the optical fiber unit 3, the end face from which light is emitted is polished by a technique such as CMP (chemical mechanical polishing) at an angle that provides a desired coupling with the light input unit 102. The end face from which light is emitted is a face facing the face of the optical circuit board 1 in the positive Z-axis direction.

[0031] The optical fiber unit 3 includes an optical fiber 301 having a core 302 and a cladding 303 , and an optical fiber holding member 304 which is a component for holding the optical fiber 301 .

[0032] [Optical Fiber 301] Examples of the optical fiber 301 include a single mode fiber, a multimode fiber, a quartz fiber, and a plastic fiber.

[0033] For example, an adhesive is provided between the outer peripheral surface of the clad 303 and the optical fiber holding member 304. The clad 303 is held by the optical fiber holding member 304 via this adhesive.

[0034] [Optical fiber holding member 304] For example, a cylindrical capillary is used as the optical fiber holding member 304. However, the optical fiber holding member 304 is not limited to this, and may be, for example, a combination of a substrate having a groove with a V-shaped cross section and a lid that closes the groove with the cladding 303 placed in the groove.

[0035] [Adhesive 5] The adhesive 5 shown in Fig. 1 is an adhesive after the uncured adhesive has cured. The adhesive 5 is a photocurable resin. In the following, the adhesive 5 may be referred to as a "cured adhesive" to distinguish it from the uncured adhesive. Note that the adhesive 5 is omitted in Fig. 2 to make it easier to understand the positional relationship between the light input section 102 and the center of gravity CG of the guide 2.

[0036] <Optical waveguide connection device D1> Next, a configuration example of the optical waveguide connection device D1 according to an embodiment of the present disclosure will be described with reference to Fig. 3. Fig. 3 is a diagram showing a configuration example of the optical waveguide connection device D1 according to an embodiment of the present disclosure. In the following, for the sake of simplicity, the optical waveguide connection device D1 may be simply referred to as the "connection device D1".

[0037] [Connection device D1] The connection device D1 is a device that actively aligns and connects the optical input section 102 on the optical circuit board 1 and the optical fiber 301.

[0038] Active alignment means that the light intensity received by the light receiving unit 6 is measured by a measuring device (not shown), and the optical axes of the optical fiber 301 and the light input unit 102 are aligned so that the measured light intensity is maximized.

[0039] In this embodiment, active alignment may be referred to as "active alignment".

[0040] The connection device D1 includes a sample stage 11, a sample adjustment mechanism 12, an optical fiber unit 3, an optical fiber alignment mechanism 31, a light receiving unit 6, a light receiving unit alignment mechanism 61, an adhesive supply unit 41, an adhesive curing unit 51, an adhesive curing unit adjustment mechanism 52, and a control unit C1.

[0041] [Sample Stage 11] The sample stage 11 is a platform on which the optical circuit-board 1 is placed. There is no restriction on the type of sample stage 11 as long as it is possible to place the optical circuit-board 1 on the sample stage 11. For example, the sample stage 11 may be provided with suction holes for suctioning the optical circuit-board 1, and the optical circuit-board 1 may be brought into close contact with the sample stage 11 by applying negative pressure to the suction holes.

[0042] [Sample preparation mechanism 12] The sample adjustment mechanism 12 is a mechanism for adjusting the position of the optical circuit board 1 on the sample stage 11. Specifically, the position of the optical circuit board 1 is adjusted so that the light emitted from the optical fiber unit 3 is approximately coupled with the optical circuit board 1. The sample adjustment mechanism 12 is, for example, a unit combining a linear stage. For example, a camera may be used to adjust the position of the optical circuit board 1.

[0043] [Optical fiber alignment mechanism 31] The optical fiber aligning mechanism 31 is a movable stage for adjusting the optical fiber unit 3. The optical fiber aligning mechanism 31 is realized by combining, for example, a linear motion stage using a linear ball guide, a gonio stage, etc. The optical fiber aligning mechanism 31 is configured so as to be operable in six mutually different axial directions.

[0044] The six axial directions include, for example, the X-axis direction, the Y-axis direction, and the Z-axis direction, as well as the rotation directions around each of these axes.

[0045] The movable direction of the optical fiber aligning mechanism 31 may be any one of six axes. However, when the movable direction of the optical fiber aligning mechanism 31 is six axes, fine operation can be realized in each step of the optical waveguide connection method described later, improving the accuracy of alignment and realizing high-quality and highly efficient optical coupling.

[0046] [Light receiving section 6] The light receiving section 6 is a unit that receives the light emitted from the optical circuit board 1, and is, for example, an optical fiber.

[0047] [Light receiving unit alignment mechanism 61] The light receiving unit alignment mechanism 61 is a movable stage for adjusting the position of the light receiving unit 6. The light receiving unit alignment mechanism 61 is realized by combining, for example, a linear motion stage using a linear ball guide, a gonio stage, etc. The light receiving unit alignment mechanism 61 is configured so as to be operable in six mutually different axial directions.

[0048] The six axial directions include, for example, the X-axis direction, the Y-axis direction, and the Z-axis direction, as well as the rotation directions around each of these axes.

[0049] The movable direction of the light-receiving unit alignment mechanism 61 may be any one of six axes. However, when the light-receiving unit alignment mechanism 61 is movable in six axes, fine movements can be realized in each step of the optical waveguide connection method described below, improving the alignment accuracy and enabling high-quality and highly efficient optical coupling to be realized.

[0050] [Adhesive supply unit 41] The adhesive supplying section 41 is a unit that supplies uncured adhesive 4 to the inner region of the guide 2 on the optical circuit-board 1. The inner region of the guide 2 is a region surrounded by each side portion 2a of the guide 2.

[0051] [Uncured adhesive 4] The uncured adhesive 4 is adhesive before being cured by the adhesive curing unit 51. The method for supplying the uncured adhesive 4 to the inner region of the guide 2 is not limited, and may be, for example, a dispenser. The amount of uncured adhesive 4 supplied to the inner region of the guide 2 is, for example, 1 [nL] to 1000 [μL].

[0052] [Adhesive curing section 51] The adhesive curing unit 51 is a light source, such as an ultraviolet light source, for fixing the optical fiber unit 3 on the optical circuit board 1 in the inner region of the guide 2 by curing the uncured adhesive 4 supplied to the inner region of the guide 2 arranged on the optical circuit board 1. In the optical waveguide connection structure 100 of the present disclosure, three adhesive curing units 51 are used.

[0053] The adhesive curing portions 51 are provided on the connecting device D1 at equal intervals (120° intervals) on a concentric circle of an imaginary axis that passes through the center of gravity CG and is parallel to the Z axis.

[0054] The distance from the position where each adhesive curing portion 51 is disposed to the center of gravity CG of the guide 2 is equal.

[0055] Each adhesive curing portion 51 is disposed above each vertex portion 2 b of the guide 2 disposed on the optical circuit board 1 .

[0056] The distance from each adhesive curing portion 51 to the upper surface 11a of the sample stage 11 is set to, for example, 1 mm to 50 mm.

[0057] [Adhesive hardening adjustment mechanism 52] The adhesive curing portion adjustment mechanism 52 is a movable mechanism for adjusting the position of the adhesive curing portion 51 .

[0058] Although the adhesive curing unit adjustment mechanism 52 may be a unit combining linear motion stages, it is preferable that the adhesive curing unit 51 is a unit that imparts rotational motion to the adhesive curing unit 51 in order to uniformly cure the uncured adhesive 4 supplied to the inner region of the guide 2. Such a unit may be a goniostage, a rotation stage, or the like.

[0059] The adhesive curing section adjustment mechanism 52 adjusts the position of the adhesive curing section 51 so that, when the uncured adhesive 4 is cured by the adhesive curing section 51, the uncured adhesive 4 gradually hardens in the inner region of the guide 2 from near the inner surface of each side portion 2a toward the center of gravity CG of the guide 2.

[0060] In adjusting the position of the adhesive curing portion 51 by the adhesive curing portion adjustment mechanism 52, first, the uncured adhesive 4 present near the inner surface of each side portion 2a constituting the guide 2 is cured.

[0061] Thereafter, the adhesive curing unit 51 is continuously rotated so that the ultraviolet ray irradiation destination of the adhesive curing unit 51 is directed from the inner surface of each side portion 2a of the guide 2 toward the center of gravity CG. The rotational drive speed at this time is set in the range of 0.1° / min to 10° / min.

[0062] By continuously rotating the plurality of adhesive curing units 51 around the guide 2, unevenness in ultraviolet irradiation, that is, unevenness in curing, can be minimized.

[0063] [Control unit C1] The control unit C1 is a microcomputer or the like that controls the operations of the members that make up the connection device D1.

[0064] For example, the control unit C1 controls (active alignment) the optical fiber alignment mechanism 31 so that the light intensity detected by the light receiving unit 6 becomes maximum.

[0065] Furthermore, the control unit C1 controls the supply amount of the adhesive supply unit 41, the irradiation intensity of the adhesive curing unit 51, and the irradiation time.

[0066] Furthermore, the control unit C1 controls the adhesive curing unit adjustment mechanism 52 so that the adhesive curing unit 51 is at a specific irradiation position and irradiation angle.

[0067] <Optical waveguide connection method> Next, with reference to FIG. 4 and FIG. 5, an optical waveguide connection method using the optical waveguide connection structure 100 and the connection device D1 will be described in detail.

[0068] FIG. 4 is a flowchart for explaining an optical waveguide connection method using a connection device D1, and FIG. 5 is a schematic top view showing the optical waveguide connection method according to an embodiment of the present disclosure.

[0069] In the connection device D1, first, a sample position adjustment step (ST10) is performed.

[0070] In the sample position adjustment step, the optical circuit-board 1 is placed on the sample stage 11, and the position of the optical circuit-board 1 is adjusted by the sample adjustment mechanism 12.

[0071] Next, in the connecting device D1, an adhesive supplying step (ST20) is performed.

[0072] In the adhesive supplying step, the uncured adhesive 4 is supplied by an adhesive supplying unit 41 to an inner region of a guide 2 arranged on the optical circuit board 1 so as to take in the optical input unit 102 .

[0073] At this time, each side portion 2a constituting the guide 2 functions as a stopper that prevents the uncured adhesive 4 supplied to the inner region of the guide 2 from flowing out to the outside of the guide 2. Since the stopper can determine the shape of the periphery of the liquid uncured adhesive 4, the uncured adhesive 4 supplied to the inner region of the guide 2 is uniformly formed from the center of gravity CG of the guide 2 to each side portion 2a of the guide 2, and is also uniformly formed from the center of gravity CG of the guide 2 to each vertex portion 2b of the guide 2. As a result, a uniform fillet is formed from the center of gravity CG of the guide 2 to each side portion 2a or each vertex portion 2b.

[0074] Next, in the connection device D1, an optical fiber unit alignment step (ST30) is performed.

[0075] Specifically, the optical fiber aligning mechanism 31 aligns the optical fiber unit 3 with respect to the light input section 102. That is, the optical fiber aligning mechanism 31 sets the optical fiber unit 3 to an alignment condition state in which the light intensity acquired by the light receiving section 6 is maximized.

[0076] If the light intensity acquired by the light receiving unit 6 has not reached the maximum (ST31, NO), the process from ST30 onwards is repeatedly executed.

[0077] When the light intensity acquired by the light receiving unit 6 reaches a maximum (ST31, YES), the optical fiber unit alignment process is completed.

[0078] The accuracy of the alignment is, for example, on the order of nanometers. However, the accuracy of the alignment is not limited to the order of nanometers and may be on the order of micrometers.

[0079] Next, in the connecting device D1, an adhesive curing step (ST40) is performed.

[0080] In the adhesive curing step, the adhesive curing unit 51, which is installed so as to irradiate ultraviolet rays toward each vertex 2b of the guide 2, cures the uncured adhesive 4. As a result, the optical fiber unit 3 is connected to the optical circuit board 1.

[0081] Furthermore, in the connecting device D1, an adhesive curing portion adjusting step (ST50) is performed during the adhesive curing step. The adhesive curing portion adjusting step will be described in detail with reference to Figures 6A to 6C.

[0082] 6A to 6C are diagrams for explaining the adhesive curing portion adjusting step.

[0083] FIG. 6A shows a cross section along the XZ plane of the optical waveguide connection structure 100 when the adhesive curing process is started.

[0084] When the adhesive curing step is started, the inclination angle 51a of the adhesive curing portion 51 with respect to the normal line perpendicular to the optical circuit-board 1 is set in the range of 0° to 20°.

[0085] When the adhesive hardening process is started, the adhesive hardening section 51 causes the unhardened adhesive 4 supplied to the inner area of ​​the guide 2, that is present near the inner surfaces of each side portion 2a that constitutes the guide 2, to begin to harden, and changes into adhesive 5 after hardening.

[0086] In the process of forming the cured adhesive 5, the adhesive curing unit 51 is continuously rotated so that the ultraviolet ray irradiation destination of the adhesive curing unit 51 is directed from the inner surface of each side portion 2a of the guide 2 toward the center of gravity CG. This changes the ultraviolet ray irradiation direction of the adhesive curing unit 51. The rotation drive speed at this time is set in the range of 0.1° / min to 10° / min.

[0087] FIG. 6B shows a state in which the adhesive curing unit 51 that has been rotationally driven is tilted by 20[°].

[0088] When the adhesive curing portion 51 is further rotated, the inclination of the adhesive curing portion 51 increases, as shown in Fig. 6C. As a result, the uncured adhesive 4 supplied to the inner region of the guide 2 changes entirely into cured adhesive 5.

[0089] In this way, by the adhesive curing section adjustment mechanism 52 adjusting the angle and position of the adhesive curing section 51, the uncured adhesive 4 supplied to the inner area of ​​the guide 2 can be gradually hardened from the inner surface of each side portion 2a of the guide 2 toward the center of gravity CG.

[0090] As a result, the peripheral portion of the optical fiber unit 3 is gradually hardened, and then the optical fiber unit 3 is irradiated with ultraviolet light from the adhesive curing portion 51, the uncured adhesive 4 on the surface of the optical fiber unit 3 is cured, and the optical fiber unit 3 is connected to the optical circuit board 1.

[0091] As a result, unlike the technology disclosed in Patent Document 1, it is possible to minimize the effect of misalignment of the optical fiber unit 3 due to the curing shrinkage of the uncured adhesive 4 without using parts such as a first ferrule, a second ferrule, and a stopper.

[0092] Furthermore, the above process makes it possible to realize stable, high-quality, and highly efficient optical coupling with a low-cost and simple configuration.

[0093] According to one embodiment of the present disclosure, it is possible to construct an optical waveguide connection structure, an optical waveguide connection device, and an optical waveguide connection method that can suppress the effect of positional misalignment between an optical fiber and an optical input portion with a simple configuration and achieve highly efficient optical coupling.

[0094] In this disclosure, an optical waveguide connection structure, an optical waveguide connection device, and an optical waveguide connection method have been described using an equilateral triangular guide 2; however, the shape of the guide 2 is not limited to an equilateral triangle, and may be a regular polygon such as a regular square or a regular pentagon.

[0095] When the shape of the guide 2 is a regular square, it is preferable that the adhesive curing parts 51 are arranged above each of the four vertices 2b, and when the shape of the guide 2 is a regular pentagon, it is preferable that the adhesive curing parts 51 are arranged above each of the five vertices 2b. This is because unevenness in ultraviolet irradiation can be minimized by arranging the adhesive curing parts 51 above each of the multiple vertices 2b and continuously rotating the adhesive curing parts 51.

[0096] Even if a ring-shaped guide 2 not including a vertex portion 2b is used instead of a regular polygonal guide 2, the adhesive can be hardened by providing adhesive hardening portions 51 at equal intervals on a concentric circle of a virtual axis passing through the center of gravity CG and parallel to the Z axis.

[0097] However, when a ring-shaped guide 2 that does not include the apex portion 2b is used, the amount of adhesive present in the second region away from the adhesive hardening portion 51 becomes relatively greater than the amount of adhesive present in the first region near the adhesive hardening portion 51.

[0098] As a result, it may take a long time for the adhesive present in the second region to harden even if the adhesive hardening unit 51 is continuously rotated. Therefore, it is preferable that the shape of the guide 2 is set to a regular polygon.

[0099] Although the present disclosure has been fully described in connection with the preferred embodiment with reference to the accompanying drawings, various changes and modifications will be apparent to those skilled in the art. Such changes and modifications should be understood to be included within the scope of the present disclosure as defined by the appended claims, unless they deviate from the scope of the present disclosure. In addition, changes in the combination and order of elements in the embodiments may be made without departing from the scope and spirit of the present disclosure.

[0100] It should be noted that, for example, the following aspects are also understood to fall within the technical scope of the present disclosure.

[0101] (1) An optical waveguide connection structure includes an optical fiber unit having an optical fiber and an optical fiber holding member that holds the optical fiber, an optical input portion provided at an end of the optical waveguide, and an optical circuit board having a regular polygonal guide provided to surround the optical input portion, and the optical fiber unit is connected to the optical input portion via an adhesive present in the inner region of the guide.

[0102] (2) The light input portion is disposed at a position overlapping with the center of gravity of the guide.

[0103] (3) An optical waveguide connection device includes a sample stage on which an optical circuit board is placed, an adhesive supplying unit that supplies uncured adhesive to an inner area of ​​a regular polygonal guide that is arranged to surround an optical input unit provided on the optical circuit board, a light receiving unit that receives light emitted from the optical circuit board, an optical fiber alignment mechanism that aligns an optical fiber with respect to the optical input unit while the uncured adhesive is supplied to the inner area of ​​the guide so that the light intensity received by the light receiving unit is maximized, an adhesive curing unit that cures the uncured adhesive while the optical fiber is aligned with the optical input unit, and an adhesive curing unit adjustment mechanism that adjusts the angle and position of the adhesive curing unit when the uncured adhesive hardens.

[0104] (4) The adhesive curing section is positioned to cure the uncured adhesive from the apex of the guide toward the center of gravity of the guide.

[0105] (5) The adhesive curing portion adjustment mechanism adjusts the angle and position of the adhesive curing portion starting from the vertex of the guide so that the uncured adhesive hardens from the edge of the guide toward the center of gravity of the guide.

[0106] (6) An optical waveguide connection method includes an uncured adhesive supplying step of supplying uncured adhesive to an inner area of ​​a regular polygonal guide that is arranged to surround an optical input section provided on an optical circuit board; an alignment step of aligning an optical fiber with respect to the optical input section while the uncured adhesive is supplied to the inner area of ​​the guide so that an intensity of light detected by a light receiving section that receives light emitted from the optical circuit board is maximized; an adhesive curing step of curing the uncured adhesive while the optical fiber is aligned with the optical input section; and an adhesive curing portion adjusting step of adjusting an angle and position of an adhesive curing portion that cures the uncured adhesive in the adhesive curing step.

[0107] (7) In the optical waveguide connection method, in an adhesive curing portion adjusting step, the adhesive curing portion is adjusted starting from the vertex of the guide so that the uncured adhesive hardens from the side of the guide toward the center of gravity of the guide. [Industrial Applicability]

[0108] An embodiment of the present disclosure is suitable for an optical waveguide connection device. In addition, the optical waveguide connection structure, optical waveguide connection device, and optical waveguide connection method according to the present disclosure can permanently connect an optical fiber and an optical waveguide on an optical circuit board with high precision, and therefore can be applied in fields such as high-speed optical communications as represented by silicon photonics and high-precision sensing using laser light. [Explanation of symbols]

[0109] 1 Optical circuit board 2 Guide 2a Edge 2b Apex 3 Optical fiber unit 4 Uncured adhesive 5. Glue 6 Light receiving section 11 Sample Stage 11a Top side 12 Sample adjustment mechanism 31 Optical fiber alignment mechanism 41 Adhesive supply section 51 Adhesive hardening section 51a Tilt angle 52 Adhesive hardening adjustment mechanism 61 Light receiving unit alignment mechanism 100 Optical waveguide connection structure 101 Optical waveguide 102 Optical input section 301 Optical Fiber 302 Cores 303 Clad 304 Optical fiber holding member C1 Control section CG center of gravity D1 Optical Waveguide Connection Device

Claims

1. an optical fiber unit having an optical fiber and an optical fiber holding member for holding the optical fiber; Adhesive and an optical circuit board having an optical input section provided at an end of an optical waveguide, and a regular polygonal guide provided so as to surround the optical input section, partitioning an area, and preventing the adhesive from flowing out; Equipped with the optical fiber unit is in contact with the inside of the guide, and the adhesive is supplied into a gap between the guide and the optical fiber unit. Optical waveguide connection structure.

2. An optical waveguide connection structure as described in Claim 1, wherein the optical input portion is positioned at a position overlapping with the center of gravity of the guide.

3. The guide is an equilateral triangle; The diameter of the optical fiber unit is between 0.5 mm and 5 mm; The side of the guide is 0.5√3 mm to 5√3 mm.

3. The optical waveguide connection structure according to claim 1 or 2.

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