Optical waveguide connection method and optical waveguide connection device

Abstract

A method for connecting an optical waveguide includes adjusting a position of a photoelectric substrate (1), supplying an adhesive (3) to a vicinity of a light input section on the photoelectric substrate, aligning an optical fiber block (2) holding an optical fiber (2a) with respect to the photoelectric substrate such that an intensity of light emitted from the photoelectric substrate is maximum, and connecting the optical fiber block (2) to the photoelectric substrate in a state where the optical fiber block (2) is aligned with the photoelectric substrate. When the optical fiber block holding the optical fiber is aligned with the photoelectric substrate, the curing of the adhesive is started, the degree of curing of the adhesive and the curing time of the adhesive are measured during the curing of the adhesive, and the alignment of the optical fiber block holding the optical fiber with respect to the photoelectric substrate is repeated in a state where the degree of curing is equal to or less than a certain threshold value so that the intensity of the light emitted from the photoelectric substrate becomes maximum.

Description

Technical Field

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

[0002] In recent years, the use of light has been studied in the fields of high-speed communication, large-capacity communication, and sensing. In particular, the technology called "silicon photonics" that forms an optical circuit on a silicon substrate through the CMOS (Complementary Metal Oxide Semiconductor) process, like semiconductor electronic circuits, has attracted much attention. The optical circuit formed by silicon photonics is a circuit of fine size with a light control function. The optical circuit is formed with optical input and output parts and optical modulators. They are connected to each other by sub-micron-level fine optical waveguides. In order to connect the optical waveguide to external transmission bodies such as optical fibers with high precision, various optical interfaces are actively developed.

[0003] Typically, as a method for connecting an optical fiber to an optical waveguide on an optical circuit substrate (i.e., fiber-to-chip connection), the following method is adopted: an end face of a light input portion formed on the optical circuit substrate and a connection end face of an optical fiber array or optical fiber block in which one or more optical fibers are bundled are bonded and fixed as a whole via an adhesive.

[0004] It is known that when the optical fiber block is fixed to the optical circuit board using this method, when the adhesive is cured, the relative position of the optical circuit board and the optical fiber block shifts due to the curing and shrinkage of the adhesive, resulting in connection loss.

[0005] Patent document 1 discloses the following technology: by providing a groove along the end (around) of the lower surface of a ferrule that holds the optical fiber, adhesive overflowing from the lower surface of the ferrule is absorbed by the groove through a capillary phenomenon, thereby preventing adhesive from adhering to the side of the ferrule and suppressing positional deviation of the ferrule in the parallel direction caused by curing shrinkage.

[0006] Prior Art Literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2019-144434 Summary of the invention

[0009] A method for connecting an optical waveguide according to one embodiment of the present disclosure includes: adjusting the position of an optical circuit substrate, supplying an adhesive near an optical input portion on the optical circuit substrate, aligning an optical fiber block holding an optical fiber relative to the optical circuit substrate so that the intensity of light emitted from the optical circuit substrate becomes maximum, starting curing of the adhesive while the optical fiber block is aligned relative to the optical circuit substrate, measuring the degree of curing of the adhesive, measuring the curing time of the adhesive during the curing of the adhesive, and aligning the optical fiber block holding the optical fiber relative to the optical circuit substrate with reference to the degree of curing of the adhesive and the curing time of the adhesive so that the intensity of light emitted from the optical circuit substrate becomes maximum.

[0010] An optical waveguide connection device according to one embodiment of the present disclosure includes: a sample stage on which an optical circuit substrate is disposed; an adhesive supplying unit that supplies adhesive near a light input unit disposed on the optical circuit substrate; a light receiving unit that receives light emitted from the optical circuit substrate; an optical fiber centering mechanism that aligns an optical fiber block holding an optical fiber relative to the optical circuit substrate in a state where the adhesive is supplied so that the intensity of light received by the light receiving unit becomes maximum; an adhesive curing unit that cures the adhesive in a state where the optical fiber block is aligned relative to the optical circuit substrate; an adhesive curing time detecting mechanism that detects the curing time of the adhesive when curing the adhesive; a curing degree measuring unit that measures the curing degree of the adhesive; and a control unit that controls the optical fiber centering mechanism, wherein the optical fiber centering mechanism aligns the optical fiber block holding the optical fiber relative to the optical circuit substrate with reference to the curing degree of the adhesive and the curing time of the adhesive under the control of the control unit so that the intensity of light emitted from the optical circuit substrate becomes maximum. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a diagram showing a configuration example of the optical waveguide connecting device according to the first embodiment of the present disclosure.

[0012] Figure 2 This is a control system diagram of the optical waveguide connection device according to Embodiment 1 of the present disclosure.

[0013] Figure 3 This is a flowchart showing the optical waveguide connection method according to Embodiment 1 of the present disclosure.

[0014] Figure 4 This is a diagram for explaining changes in resistance value according to Embodiment 1 of the present disclosure.

[0015] Figure 5 It is a diagram showing a configuration example of an optical waveguide connecting device according to Embodiment 2 of the present disclosure.

[0016] Figure 6 It is a control system diagram of the optical waveguide connection device according to Embodiment 2 of the present disclosure.

[0017] Figure 7 This is a flowchart showing a method for connecting an optical waveguide according to Embodiment 2 of the present disclosure.

[0018] Figure 8 This is a diagram for explaining changes in the degree of curing according to the second embodiment of the present disclosure. DETAILED DESCRIPTION

[0019] In the prior art disclosed in Patent Document 1, the ferrule needs to be additionally finely processed, which may increase the manufacturing cost. In addition, when supplying the adhesive, it needs to stay on the coated area on the optical circuit substrate to some extent, and the viscosity of the adhesive and the amount of adhesive applied are limited.

[0020] The purpose of the non-limiting embodiments of the present disclosure is to provide an optical waveguide connection method and an optical waveguide connection device that can suppress the positional deviation of the optical input part of the optical fiber and the optical circuit substrate with a simple structure without relying on the shape of the adhesive, thereby achieving efficient optical coupling.

[0021] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the drawings.

[0022] In addition, in this specification and the drawings, the same symbols are given to the structural elements having substantially the same functions, so that repeated descriptions are omitted. In the following figures, the shapes, thicknesses, lengths, etc. of the structural members shown respectively are different from the shapes, thicknesses, lengths, etc. of the actual structural members in the production of the drawings. Furthermore, the materials of the structural members are not limited to the materials described in this embodiment.

[0023] exist Figure 1 Hereinafter, the X-axis direction, the Y-axis direction, and the Z-axis direction respectively represent the direction parallel to the X-axis, the direction parallel to the Y-axis, and the direction parallel to the Z-axis. The X-axis direction and the Y-axis direction are orthogonal to each other. The X-axis direction and the Z-axis direction are orthogonal to each other. The Y-axis direction and the Z-axis direction are orthogonal to each other. The XY plane represents an imaginary plane parallel to the X-axis direction and the Y-axis direction. The XZ plane represents an imaginary plane parallel to the X-axis direction and the Z-axis direction. The YZ plane represents an imaginary plane parallel to the Y-axis direction and the Z-axis direction. In addition, Figure 1 Hereinafter, the direction indicated by the arrow in the X-axis direction is referred to as the positive direction of the X-axis, and the direction opposite to the arrow is referred to as the negative direction of the X-axis. Figure 1 Hereinafter, the direction indicated by the arrow in the Y-axis direction is referred to as the positive direction of the Y-axis, and the direction opposite to the arrow is referred to as the negative direction of the Y-axis. Figure 1Hereinafter, the direction indicated by the arrow in the Z-axis direction is defined as the positive Z-axis direction, and the direction opposite to the arrow is defined as the negative Z-axis direction. The Z-axis direction is, for example, equal to the vertical direction or the up-and-down direction, such as the thickness direction of the rectangular optical circuit substrate 1, and the X-axis direction and the Y-axis direction are, for example, equal to the horizontal direction or the left-and-right direction, such as the long side direction and the short side direction of the rectangular optical circuit substrate 1.

[0024] [Implementation Method 1]

[0025] <Optical waveguide connection device>

[0026] First, refer to Figure 1 as well as Figure 2 , an optical waveguide connecting device D1 according to Embodiment 1 of the present disclosure is described. Figure 1 is a diagram showing a configuration example of an optical waveguide connection device D1 according to Embodiment 1 of the present disclosure, Figure 2 This is a control system diagram of the optical waveguide connection device D1 according to the first embodiment of the present disclosure. The optical waveguide connection device D1 is a device that actively aligns (centers) and connects the optical circuit substrate 1 and the optical fiber block 2. Active alignment means that the optical axis of the optical fiber block 2 and the optical circuit substrate 1 is aligned (aligned) by measuring the light intensity received by the light receiving unit 50 by a measuring device (not shown) so that the measured light intensity becomes the maximum. In this first embodiment, active alignment is sometimes referred to as "active alignment".

[0027] The optical waveguide connection device D1 includes at least a sample stage 10, an optical fiber centering mechanism 20, an adhesive supply unit 30, an adhesive curing unit 40, an adhesive curing time detection mechanism 40a, a light receiving unit 50, a resistance measuring unit 60, and a control unit C1. Furthermore, the optical waveguide connection device D1 may also include a sample adjustment mechanism 11 and a light receiving unit centering mechanism 51.

[0028] The sample stage 10 is set on the fixed stage 100 and is a stage for setting the optical circuit substrate 1. The sample stage 10 is not limited to any type as long as it can set the optical circuit substrate 1. For example, the sample stage 10 can be provided with an adsorption hole for adsorbing the optical circuit substrate 1, and the optical circuit substrate 1 is brought into close contact with the sample stage 10 by applying negative pressure to the adsorption hole.

[0029] The sample adjustment mechanism 11 is provided between the fixed stage 100 and the sample stage 10, and is a mechanism for adjusting the position of the optical circuit substrate 1 on the sample stage 10. Specifically, the position of the optical circuit substrate 1 is adjusted so that the light emitted from the optical fiber block 2 is roughly coupled with the optical circuit substrate 1. The sample adjustment mechanism 11 is, for example, a unit obtained by combining two linear motion stages in orthogonal directions. For example, a camera or the like can also be used for adjusting the position of the optical circuit substrate 1.

[0030] The optical fiber centering mechanism 20 is provided near the sample stage 10 of the fixed stage 100, and is a movable stage for making the first movable part 20e movable in the XYZ axis directions relative to the first fixed part 20d to perform active alignment of the optical fiber block 2 held by the first movable part 20e. In a state where the adhesive 3 is supplied, the optical fiber centering mechanism 20 aligns the optical fiber block 2 holding the optical fiber 2a relative to the optical circuit substrate 1 so that the intensity of the light received by the light receiving part 50 becomes maximum. Specifically, during the period when the adhesive 3 is cured by the adhesive curing part 40 described later, the alignment by the optical fiber centering mechanism 20 is repeated even when the resistance value measured by the resistance measuring part 60 described later is below the threshold value. Here, the optical fiber block 2 is composed of an optical fiber 2a and a holder 2b. The optical fiber 2a is a medium for transmitting light, such as a single-mode optical fiber, a multi-mode optical fiber, a quartz optical fiber, or a plastic optical fiber. The optical fiber block 2 is not limited to any type as long as it holds the optical fiber 2a. The optical fiber centering mechanism 20 is realized by combining a linear motion table or an angle measuring table using a linear ball guide, for example. In the optical fiber centering mechanism 20, a motor 20a and an encoder 20b are respectively provided for each axial direction. The position information of the optical fiber block 2 detected by the encoder 20b is input to the control unit C1. The first movable part 20e of the optical fiber centering mechanism 20 is configured to be movable in six axial directions different from each other, for example. The six axial directions include, for example, the X-axis direction, the Y-axis direction, the Z-axis direction, and the rotation direction centered on each of these axes. In addition, the movable direction of the optical fiber centering mechanism 20 can also be any one of the six axes. However, in the case where the movable direction of the optical fiber centering mechanism 20 is six axes, since fine movements can be achieved in each process of the optical waveguide connection method described later, the accuracy of the centering is improved, and high-quality and efficient optical coupling can be achieved.

[0031] The adhesive supply unit 30 is a unit that supplies the adhesive 3 to the vicinity of the light input unit (not shown) on the optical circuit substrate 1. The adhesive 3 is composed of a photocurable or thermosetting resin such as an acrylic resin, an epoxy resin, an acrylic epoxy resin, or a silicone resin. The adhesive supply unit 30 is, for example, a dispenser. The adhesive supply unit 30 is not limited to any type as long as it can supply the adhesive 3 to the optical circuit substrate 1. The supply amount of the adhesive 3 supplied by the adhesive supply unit 30 is, for example, 10 [nL] to 1000 [μL].

[0032] The adhesive curing unit 40 is a unit for curing the adhesive 3 supplied to the optical circuit substrate 1, thereby fixing the optical fiber block 2 to the optical circuit substrate 1, while the optical fiber block 2 is aligned with respect to the optical circuit substrate 1. The adhesive curing unit 40 is, for example, an ultraviolet light source, and a heater may be used depending on the type of the adhesive 3. In the optical waveguide connection device D1 of the present disclosure, one adhesive curing unit is used as the ultraviolet light source, but a plurality of adhesive curing units may be provided depending on the structure of the connection.

[0033] The adhesive curing time detection mechanism 40a is an incrementing timer that detects the time for the adhesive 3 to be cured by the adhesive curing unit 40. Time information detected by the adhesive curing time detection mechanism 40a is input to the control unit C1.

[0034] The light receiving unit 50 is a unit that receives light emitted from the optical circuit board 1, and is, for example, an optical fiber. The intensity information of the light received by the light receiving unit 50 is input to the control unit C1.

[0035] The light receiving unit centering mechanism 51 is disposed in the vicinity of the sample stage 10 of the fixed table 100 opposite to the optical fiber centering mechanism 20, and is a movable table for adjusting the position of the light receiving unit 50 held by the second movable portion 51e by making the second movable portion 51e movable in the XYZ axis directions relative to the second fixed portion 51d. The light receiving unit centering mechanism 51 is realized by, for example, combining a linear motion table or an angle measuring table using a linear ball guide. The second movable portion 51e of the light receiving unit centering mechanism 51 is, for example, configured to be able to operate in six different axis directions. The six axis directions include, for example, the X-axis direction, the Y-axis direction, the Z-axis direction, and the rotation direction centered on these axes. In addition, the movable direction of the light receiving unit centering mechanism 51 can also be any one of the six axes. However, when the light receiving unit centering mechanism 51 is movable in six directions, fine movements can be achieved in each step of the optical waveguide connection method described later, so the accuracy of centering is improved, and high-quality and efficient optical coupling can be achieved.

[0036] The resistance measuring unit 60 functions as an example of a curing degree measuring unit that measures the curing degree of the adhesive 3, and is a unit that measures the curing degree of the adhesive 3 by measuring the resistance value applied to the optical fiber block 2 when the optical circuit substrate 1 and the optical fiber block 2 are actively aligned. The resistance measuring unit 60 is provided at the holding portion of the optical fiber block 2, and is, for example, a piezoelectric force sensor. The voltage and force information measured by the resistance measuring unit 60 are input to the control unit C1. Since the viscosity increases as the curing of the adhesive 3 progresses, the resistance value measured by the resistance measuring unit 60 increases, and the optical fiber block 2 becomes unable to follow the movement of the optical fiber centering mechanism 20. Let the mass of the optical fiber block 2 be m, the moving speed of the optical fiber block 2 applied by the optical fiber centering mechanism 20 be v (t), and the viscous resistance of the adhesive 3 be η, then the blocking force F applied to the optical fiber block 2 is expressed by the following formula.

[0037] [Mathematical formula 1]

[0038]

[0039] Here, solving the equation (Formula 1) for v(t) yields the following equation.

[0040] [Mathematical formula 2]

[0041]

[0042] Therefore, as the curing of the adhesive 3 progresses, the moving speed of the optical fiber block 2 becomes slower. The alignment operation when curing the adhesive 3 by the adhesive curing unit 40 is repeated when the resistance value measured by the resistance measuring unit 60 is below the threshold value, but the threshold value of the resistance value is appropriately set according to the physical properties of the adhesive 3 used and the shape of the optical fiber block 2.

[0043] The control unit C1 is a microcomputer or the like that controls the operation of the components constituting the optical waveguide connection device D1. The control unit C1 controls the optical fiber centering mechanism 20 (active alignment) so that the intensity of light detected by the light receiving unit 50 becomes maximum. In addition, the control unit C1 controls the supply amount of the adhesive supply unit 30, the irradiation intensity and irradiation time of the adhesive curing unit 40, and the like. In addition, when the curing time detected by the adhesive curing time detection mechanism 40a does not reach the irradiation time set by the aforementioned adhesive curing unit 40, and the resistance value measured by the resistance measuring unit 60 does not reach the threshold value, the control unit C1 repeatedly controls the optical fiber centering mechanism 20 (active alignment) so that the intensity of light detected by the light receiving unit 50 becomes maximum.

[0044] <Optical waveguide connection method>

[0045] Next, refer to Figure 3 as well as Figure 4 A method for connecting optical waveguides using the optical waveguide connecting device D1 according to the first embodiment of the present disclosure will be described. Figure 3 is a flowchart showing a method for connecting an optical waveguide according to Embodiment 1 of the present disclosure. Figure 4 This is a diagram for explaining changes in resistance value according to Embodiment 1 of the present disclosure.

[0046] First, the position of the optical circuit board 1 is adjusted (step S10 ). In step S10 , the optical circuit board 1 is placed on the sample stage 10 , and the position of the optical circuit board 1 is adjusted by, for example, the sample adjustment mechanism 11 .

[0047] Next, the adhesive 3 is supplied to the vicinity of the light input portion (not shown) on the optical circuit board 1 by the adhesive supply unit 30 (step S20). The position where the adhesive 3 is supplied can be appropriately set within a range that can connect and fix the optical circuit board 1 and the optical fiber block 2, and the adhesive 3 can be supplied to multiple locations.

[0048] Next, an alignment operation of the optical fiber block 2 is performed relative to the optical circuit substrate 1 (step S30). The so-called alignment operation refers to moving the optical fiber block 2 to a given position on the XY plane relative to the light input portion (not shown) on the optical circuit substrate 1. The so-called given position refers to the position of the optical fiber block 2 on the XY plane where the intensity of the light emitted from the light output portion (not shown) of the optical circuit substrate 1 becomes the maximum according to the light incident on the light input portion via the optical fiber 2a of the optical fiber block 2. By moving the optical fiber block 2 to the given position, the optical axis of the optical fiber block 2 is aligned relative to the optical circuit substrate 1. The light emitted from the light output portion (not shown) of the optical circuit substrate 1 is received by the light receiving portion 50, and the position of the light receiving portion 50 can be adjusted by the light receiving portion alignment mechanism 51. The accuracy of the alignment of the optical axis of the optical fiber block 2 based on the action of step S30 is in the nanometer level. In addition, the accuracy of the alignment in the action of step S30 is not limited to the nanometer level, and can also be performed so as to be in the micrometer level.

[0049] Next, the resistance value applied to the optical fiber block 2 is calculated by the resistance measuring unit 60, and the reference value for calculating the curing degree of the adhesive 3 is measured (step S40). The resistance value is measured when the optical fiber block 2 is aligned in step S30, indicating the degree of force applied to the optical fiber block 2 in response to the alignment operation of the optical fiber centering mechanism 20. The resistance value is used to determine the alignment operation during the curing of the adhesive 3 described later.

[0050] Next, in a state where the optical circuit board 1 and the optical fiber block 2 are aligned via the adhesive 3, curing of the adhesive 3 is started (step S50). In step S50, the adhesive curing unit 40 irradiates the adhesive 3 with ultraviolet rays or increases the ambient temperature based on the determined curing time, thereby curing the adhesive 3.

[0051] Next, when the time detected by the adhesive curing time detection mechanism 40a after the start of curing of the adhesive 3 does not reach the set value (step S51, No), and the resistance value calculated in step S40 does not reach the threshold value (step S52, No), the optical fiber block 2 is aligned with respect to the optical circuit substrate 1 (step S60). Through step S60, the positional deviation caused by the curing shrinkage of the adhesive 3 caused by the curing of the adhesive 3 can be corrected.

[0052] Next, the resistance measuring unit 60 calculates the resistance value applied to the optical fiber block 2 in the alignment operation performed in step S60 , calculates the curing degree of the adhesive 3 based on the previously measured reference value (step S70 ), and the processing after step S50 is repeatedly performed.

[0053] like Figure 4 As shown, as the curing time of the adhesive 3 passes, the viscosity changes and the resistance value increases. When the resistance value applied to the optical fiber block 2 calculated in step S70 reaches the threshold value (step S52, yes), the alignment operation of the optical fiber block 2 relative to the optical circuit substrate 1 is not performed, and when the curing time of the adhesive reaches the set value (step S51, yes), the curing of the adhesive 3 is terminated (step S80). In addition, the threshold value of the resistance value is appropriately set according to the physical properties of the adhesive 3 used and the shape of the optical fiber block 2.

[0054] The optical waveguides are connected through the above steps.

[0055] According to the first embodiment, the optical fiber block 2 holding the optical fiber 2a can be aligned with respect to the optical circuit substrate 1 with reference to the curing degree of the adhesive 3 and the curing time of the adhesive so that the intensity of the light emitted from the optical circuit substrate 1 becomes maximum. Specifically, as described above, after step S50, step S51, step S52, step S60, and step S70 are repeatedly performed. In this way, the positional deviation of the optical fiber 2a and the light input part of the optical circuit substrate can be suppressed with a simple structure without depending on the shape of the adhesive such as the optical fiber block 2, so that efficient optical coupling can be achieved.

[0056] [Implementation Method 2]

[0057] Hereinafter, Embodiment 2 according to the present disclosure will be described with reference to the drawings. In the following description, differences from Embodiment 1 described above will be mainly described, and description of common points will be appropriately omitted or simplified.

[0058] use Figure 5 as well as Figure 6 , an optical waveguide connection device D2 according to a second embodiment of the present disclosure is described. Figure 5 is a diagram showing a configuration example of an optical waveguide connection device D2 according to a second embodiment of the present disclosure. Figure 6 It is a control system diagram of the optical waveguide connection device D2 according to the second embodiment of the present disclosure.

[0059] The optical waveguide connecting device D2 in the second embodiment includes a curing degree measuring section 70 instead of the resistance measuring section 60 .

[0060] The curing degree measuring unit 70 is a unit for measuring the curing degree of the adhesive 3 when the adhesive 3 is cured by the adhesive curing unit 40. For example, when the adhesive 3 is epoxy resin, the curing degree measuring unit 70 is a device for calculating the curing degree by measuring the absorption spectrum of infrared light using Fourier transform infrared spectrophotometry. As the curing reaction of epoxy resin proceeds, the molecular structure changes, and the epoxy group decreases, so the peak intensity of the absorption spectrum decreases. By measuring the ratio of unreacted materials and reacted materials based on the spectral changes of the adhesive, in other words, by calculating the peak intensity ratio of the epoxy group based on the peak intensity of the structure that does not contribute to the reaction, the curing degree can be measured. The curing degree measuring unit 70 is not limited to its type as long as it can measure the curing degree of the adhesive 3. The curing degree information of the adhesive 3 measured by the curing degree measuring unit 70 is input to the control unit C1.

[0061] Here, regarding the optical waveguide connection method using the optical waveguide connection device D2 in the second embodiment, Figure 7 as well as Figure 8 To explain. Figure 7 is a flowchart showing a method for connecting an optical waveguide according to Embodiment 2 of the present disclosure. Figure 8 This is a diagram for explaining changes in the degree of curing according to the second embodiment of the present disclosure.

[0062] Step S10 , step S20 , step S30 , and step S50 are the same as those in the first embodiment.

[0063] Next, after the curing of the adhesive 3 is started (step S50), the curing degree measuring unit 70 measures the current curing degree of the adhesive 3 (step S90). In the case of an ultraviolet curing adhesive, when ultraviolet irradiation starts, the photopolymerization initiator absorbs ultraviolet rays, generates free radicals or cations, and then combines with monomers or oligomers that are the main components of ultraviolet curing to perform a polymerization reaction. At this time, the curing degree measured by the curing degree measuring unit 70 increases in proportion to the consumption of the initiator as the viscosity increases.

[0064] Next, when the time detected by the adhesive curing time detection mechanism 40a does not reach the set value (step S51, No), and the curing degree of the adhesive 3 calculated in step S90 does not reach the threshold value (step S91, No), the optical fiber block 2 is aligned with respect to the optical circuit substrate 1 (step S60), and the processing after step S50 is repeatedly performed. Through this step S60, the positional deviation caused by the curing shrinkage of the adhesive 3 caused by the curing of the adhesive 3 can be corrected.

[0065] like Figure 8 As shown, the curing degree increases as the curing time of the adhesive 3 passes. When the curing degree of the adhesive 3 calculated in step S90 reaches the threshold value (step S91, yes), the alignment operation of the optical fiber block 2 relative to the optical circuit substrate 1 is not performed, and when the curing time of the adhesive reaches the set value (step S51, yes), the curing of the adhesive 3 is terminated (step S80).

[0066] Here, the threshold value of the curing degree measured in step S90 is, for example, 70%. In addition, the threshold value of the curing degree is not limited to 70%, and is appropriately set within the range of 50% to 99% according to the physical properties of the adhesive 3 used and the shape of the optical fiber block 2.

[0067] According to embodiment 2, as described above, after step S50, steps S90, S51, S91 and S60 are repeatedly performed, thereby being able to suppress the positional deviation of the optical input part of the optical fiber 2a and the optical circuit substrate 1 with a simple structure without relying on the shape of the adhesive such as the optical fiber block 2, thereby achieving efficient optical coupling.

[0068] In the first or second embodiment, regarding the measurement of the degree of curing, the degree of curing of the adhesive 3 can be measured all the time until the curing of the adhesive 3 is completed.

[0069] The present disclosure is fully described in association with the preferred embodiments with reference to the accompanying drawings, but various modifications or alterations will be apparent to those skilled in the art. It should be understood that such modifications or alterations are included within the scope of the present disclosure as long as they do not depart from the scope of the appended claims. In addition, the combination of elements in the embodiments or changes in the order can be implemented without departing from the scope and concept of the present disclosure.

[0070] In addition, by appropriately combining any of the above-mentioned various embodiments or variations, the respective effects can be achieved. In addition, it is possible to combine the embodiments with each other, to combine the embodiments with each other, or to combine the embodiments with the embodiments, and it is also possible to combine the features of different embodiments or embodiments with each other.

[0071] According to the present disclosure, the optical fiber block holding the optical fiber can be aligned with respect to the optical circuit substrate with reference to the curing degree of the adhesive and the curing time of the adhesive, so that the intensity of light emitted from the optical circuit substrate becomes maximum. Therefore, it is possible to provide an optical waveguide connection method and an optical waveguide connection device, which can suppress the positional deviation of the optical input portion of the optical fiber and the optical circuit substrate with a simple structure without relying on the shape of an adhesive such as an optical fiber block, thereby achieving efficient optical coupling.

[0072] Industrial Applicability

[0073] One embodiment of the present disclosure can be suitably used in an optical waveguide connection method and an optical waveguide connection device. In addition, the optical waveguide connection method and the optical waveguide device according to the above-mentioned embodiment of the present disclosure can efficiently and permanently connect an optical fiber block and an optical circuit substrate, and thus can be applied to fields such as high-speed optical communication represented by silicon photonics and high-precision sensing using lasers.

[0074] Explanation of symbols

[0075] 1 Optical circuit substrate

[0076] 2 Fiber Optic Blocks

[0077] 2a Fiber Optic

[0078] 2b Retaining element

[0079] 3 Adhesive

[0080] 10. Sample stage

[0081] 11. Sample adjustment mechanism

[0082] 20 Fiber centering mechanism

[0083] 20a Motor

[0084] 20b encoder

[0085] 20d 1st fixed part

[0086] 20e 1st movable part

[0087] 30 Adhesive supply unit

[0088] 40 Adhesive curing section

[0089] 40a Adhesive curing time detection mechanism

[0090] 50 Light receiving part

[0091] 51 Light receiving part centering mechanism

[0092] 51d Second fixed part

[0093] 51e Second movable part

[0094] 60 Resistance measurement unit

[0095] 70 Curing degree measurement unit

[0096] 100 Fixed table

[0097] C1 Control Unit

[0098] D1, D2 optical waveguide connection device.

Claims

1. A method for connecting an optical waveguide, comprising: Adjust the position of the optical circuit board. supplying an adhesive near the light input portion on the optical circuit substrate, aligning an optical fiber block holding an optical fiber relative to the optical circuit substrate so that the intensity of light emitted from the optical circuit substrate becomes maximum, In a state where the optical fiber block is aligned with respect to the optical circuit substrate, curing of the adhesive is started, The curing degree of the adhesive is measured. During the curing of the adhesive, the curing time of the adhesive is measured. The optical fiber block holding the optical fiber is aligned with respect to the optical circuit board with reference to the curing degree of the adhesive and the curing time of the adhesive so that the intensity of light emitted from the optical circuit board becomes maximum.

2. The optical waveguide connection method according to claim 1, wherein: When the degree of curing is equal to or less than a certain threshold, the alignment of the optical fiber block during the curing of the adhesive is repeatedly performed.

3. The optical waveguide connection method according to claim 1, wherein: Regarding the measurement of the curing degree, the curing degree is measured by measuring the resistance value applied to the optical fiber block when the optical fiber block is aligned.

4. The optical waveguide connection method according to claim 1, wherein: Regarding the measurement of the degree of curing, the degree of curing is measured by measuring the ratio of unreacted materials to reacted materials based on the change in the spectrum of the adhesive during the curing of the adhesive.

5. The optical waveguide connection method according to claim 4, wherein: Regarding the measurement of the degree of curing, the degree of curing of the adhesive is measured until the curing of the adhesive is completed.

6. An optical waveguide connection device comprising: A sample stage, for setting the optical circuit substrate; an adhesive supplying unit for supplying adhesive near a light input unit disposed on the optical circuit substrate; a light receiving unit, receiving light emitted from the optical circuit substrate; an optical fiber centering mechanism for aligning an optical fiber block holding an optical fiber relative to the optical circuit substrate in a state where the adhesive is supplied so that the intensity of light received by the light receiving portion becomes maximum; an adhesive curing unit that cures the adhesive in a state where the optical fiber block is aligned with respect to the optical circuit substrate; An adhesive curing time detection mechanism, which detects the curing time of the adhesive when the adhesive is being cured; a curing degree measuring unit for measuring the curing degree of the adhesive; and A control unit controls the optical fiber centering mechanism. Under the control of the control unit, with reference to the curing degree and curing time of the adhesive, the optical fiber centering mechanism aligns the optical fiber block holding the optical fiber relative to the optical circuit substrate so that the intensity of light emitted from the optical circuit substrate becomes maximum.

7. The optical waveguide connection device according to claim 6, wherein: When the adhesive is cured, if the degree of cure measured by the cure degree measuring unit is below a certain threshold, the optical fiber alignment mechanism aligns the optical fiber block with respect to the optical circuit board so that the intensity of light received by the light receiving unit becomes maximum.

8. The optical waveguide connection device according to claim 6, wherein: The curing degree measuring unit measures the curing degree by measuring a resistance value applied to the optical fiber block when the optical fiber centering mechanism aligns the optical fiber block.

9. The optical waveguide connection device according to claim 6, wherein: When the adhesive curing unit cures the adhesive, the curing degree measuring unit measures the curing degree by measuring a ratio of an unreacted material to a reacted material based on a change in the spectrum of the adhesive.

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