Optical adjustment device, optical adjustment method, and optical device

Abstract

The present disclosure provides an optical adjustment device, an optical adjustment method, and an optical device. The optical adjustment device comprises: a measurement light irradiation unit having a plurality of second optical fibers, which emits a plurality of lights having a single wavelength at mutually different timings through the plurality of second optical fibers; an optical fiber block that holds the emission-side ends of a first optical fiber and the plurality of second optical fibers; a light detection unit that receives and detects a plurality of reflected lights through the plurality of second optical fibers; an inclination calculation unit that compares temporal changes in the intensity of each of the plurality of reflected lights to calculate the inclination of the optical fiber block relative to an optical substrate; and a distance calculation unit that calculates the distance between the end faces of the optical substrate and the optical fiber block based on the temporal change in at least one intensity.

Description

Technical Field

[0001] The present invention relates to an optical adjustment device, an optical adjustment method and an optical component. Background Art

[0002] When connecting an optical fiber to an optical substrate of a connection target optical device such as a substrate holding the optical fiber or a substrate having a waveguide formed thereon, the optical axis of the optical fiber is adjusted so that the intensity of light propagating through the core of the optical substrate is maximized.

[0003] Adjust the optical axis of the optical fiber while bringing the optical fiber's emitting end face close to the incident end face of the optical substrate. If the optical fiber's emitting end face contacts the incident end face of the optical substrate, there is a concern of damaging the end faces of the optical fiber and the optical substrate. Damage to these end faces can reduce the efficiency of light propagation from the optical fiber to the optical substrate.

[0004] Therefore, in order to avoid contact between the optical fiber and the optical substrate, the optical axis of the optical fiber is adjusted while measuring the distance between the end faces of the optical fiber and the optical substrate.

[0005] Patent document 1 discloses a distance measuring device that emits light of different wavelengths from an optical fiber toward a connection target optical substrate, measures the intensity of the reflected light from the optical substrate, and calculates the distance between the end faces of the optical fiber and the optical substrate based on the wavelength dependence of the measured reflected light intensity.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-228444 Summary of the Invention

[0009] An optical adjustment device according to one embodiment of the present invention is an optical adjustment device used when connecting a first optical fiber to an optical substrate of a connection target, and comprises: a measuring light irradiation unit having a plurality of second optical fibers, through which a plurality of lights having a single wavelength are emitted at mutually different timings; an optical fiber block, which holds the emission-side ends of the first optical fiber and the plurality of second optical fibers; a light detection unit, which receives and detects a plurality of reflected lights corresponding to the plurality of lights reflected by the substrate end face of the optical substrate via the plurality of second optical fibers; an inclination calculation unit, which compares the time variation of the intensity of each of the plurality of reflected lights with each other and calculates the inclination of the optical fiber block relative to the optical substrate based on the comparison result; and a distance calculation unit, which calculates the distance between the end faces of the optical substrate and the optical fiber block based on the time variation of the intensity of at least one reflected light among the plurality of reflected lights.

[0010] One embodiment of the present disclosure relates to an optical adjustment method performed when connecting a first optical fiber to an optical substrate of a connection target. In the optical adjustment method, the emission-side ends of the first optical fiber and a plurality of second optical fibers for measurement are held by an optical fiber block, a plurality of lights having a single wavelength are emitted at mutually different timings via the plurality of second optical fibers, a plurality of reflected lights corresponding to the plurality of lights reflected by the substrate end face of the optical substrate are received and detected via the plurality of second optical fibers, time variations in the intensity of each of the plurality of reflected lights are compared with each other, the inclination of the optical fiber block relative to the optical substrate is calculated based on the comparison result, and the distance between the end faces of the optical substrate and the optical fiber block is calculated based on the time variation in the intensity of at least one of the plurality of reflected lights.

[0011] An optical device according to one embodiment of the present invention comprises: a first optical fiber; an optical substrate having a waveguide and being a connection target of the first optical fiber; and an optical fiber block fixed to the optical substrate, the optical fiber block holding the first optical fiber and having a plurality of insertion holes formed by a plurality of mutually connected lines forming a triangle. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram showing an optical adjustment device according to an embodiment.

[0013] Figure 2 It is a diagram showing the positional relationship of optical fibers held by the optical fiber block according to the embodiment.

[0014] Figure 3 This is a flowchart showing the procedure of optical adjustment performed by the optical adjustment device according to the embodiment.

[0015] Figure 4 This is a diagram showing an example of the detection result of reflected light obtained by the light detection unit.

[0016] Figure 5 This is a diagram showing how light emitted from the second optical fiber is reflected by the substrate end face of the optical substrate and returns as reflected light.

[0017] Figure 6 It will Figure 4 A portion of the peak is shown enlarged in the figure.

[0018] Figure 7 It is a diagram showing the correspondence between the detection result of reflected light and the inclination.

[0019] Figure 8A This is a diagram showing an example of the detection results of reflected light obtained by the light detection unit when the optical fiber block is located at different positions.

[0020] Figure 8B This is a diagram showing an example of the detection results of reflected light obtained by the light detection unit when the optical fiber block is located at different positions.

[0021] Figure 9A Graphs showing differences in reflected light when the optical fiber block is located at different positions.

[0022] Figure 9B Graphs showing differences in reflected light when the optical fiber block is located at different positions.

[0023] Figure 10 It is a diagram showing an optical device according to an embodiment.

[0024] Explanation of symbols

[0025] 10: Optical adjustment device

[0026] 30: Block end face

[0027] 41: Retainer

[0028] 42: Cover

[0029] 50: Through hole

[0030] 51: Through hole

[0031] 52: Through hole

[0032] 53: Through hole

[0033] 54: Through hole

[0034] 100: Light source

[0035] 101: Looper

[0036] 102: Optocoupler

[0037] 103: Measurement light irradiation unit

[0038] 104: Fiber Optic Block

[0039] 105: 1st optical fiber

[0040] 106: Second optical fiber

[0041] 107: Second optical fiber

[0042] 108: Second optical fiber

[0043] 109: 2nd optical fiber

[0044] 110: Light detection unit

[0045] 111: Computing Department

[0046] 112: Inclination calculation unit

[0047] 113: Distance calculation unit

[0048] 114: Adjustment device

[0049] 115: Tilt adjustment unit

[0050] 116: Distance Adjustment Unit

[0051] 120: Optical substrate

[0052] 121: Waveguide

[0053] 130: End face of substrate

[0054] 210: Optical devices

[0055] 220: Adhesive layer

[0056] AC1: Accumulated value

[0057] AC2: Accumulated value

[0058] AC3: Accumulated value

[0059] AC4: Accumulated value

[0060] AC111: Accumulated value

[0061] AC112: Accumulated value

[0062] L: Light

[0063] P1: Peak

[0064] P2: Peak

[0065] P3: Peak

[0066] P4: Peak

[0067] P11: Peak

[0068] P12: Peak

[0069] RL1: Reflected Light

[0070] RL2: Reflected Light

[0071] RL3: Reflected light

[0072] RL4: Reflected Light

[0073] tb: moment

[0074] W1: time width

[0075] W2: time width

[0076] W3: Time width

[0077] W4: Time width

[0078] Δt11: time

[0079] Δt21: time

[0080] Δt12: time DETAILED DESCRIPTION

[0081] When the optical fiber's output end face is tilted relative to the optical substrate's incident end face, the amount of reflected light from the optical substrate that can be received by the optical fiber decreases. The distance measurement device disclosed in Patent Document 1 calculates distance based on the reflected light from the optical substrate. Therefore, if the amount of reflected light received decreases, the accuracy of the distance measurement decreases. Therefore, when using the distance measurement device disclosed in Patent Document 1, it is necessary to adjust the optical fiber's output end face to be parallel to the optical substrate's incident end face before distance measurement.

[0082] The distance measuring device of Patent Document 1 cannot measure the inclination of the optical fiber with respect to the optical substrate to which it is connected, and therefore requires a separate device for measuring the inclination.

[0083] An object of the present disclosure is to provide an optical adjustment apparatus, an optical adjustment method, and an optical device capable of accurately measuring the distance of an optical fiber relative to an optical substrate to which it is connected without preparing additional equipment.

[0084] Below, with reference to the attached Figure 1 In the drawings, the same components are denoted by the same reference numerals, and their descriptions are omitted as appropriate.

[0085] Figure 1 This is a schematic diagram illustrating an optical adjustment device 10 according to an embodiment. The optical adjustment device 10 is used to adjust the optical axis of the first optical fiber 105 when connecting the first optical fiber 105 to the waveguide 121 of the optical substrate 120 to which it is connected. Specifically, the optical adjustment device 10 is configured to measure the inclination of the block end face 30 of the optical fiber block 104 relative to the substrate end face 130 of the optical substrate 120, as well as the end-face distance between the substrate end face 130 and the block end face 30. The optical substrate 120 is, for example, a substrate on which an optical circuit is formed. In addition, the substrate end face 130 is the end face of the optical substrate 120 on which light from the second optical fibers 106 to 109 is incident, and the block end face 30 is the end face of the optical fiber block 104 that is opposite to the substrate end face 130.

[0086] In the description of this embodiment, the direction in which the optical fiber block 104, which will be described later, approaches the optical substrate 120 is defined as the positive direction of the z-axis. In addition, one of the two directions forming a right-handed coordinate system with the z-axis is defined as the positive direction of the x-axis, and the other is defined as the positive direction of the y-axis. Figure 1, the direction from the front toward the depth is the positive direction of the x-axis, the upward direction is the positive direction of the y-axis, and the right direction is the positive direction of the z-axis.

[0087] The optical adjustment device 10 includes a measurement light irradiation unit 103 , an optical fiber block 104 , a light detection unit 110 , a calculation unit 111 , and an adjustment device 114 .

[0088] The measuring light irradiation unit 103 includes a plurality of second optical fibers 106 to 109 for measurement, and emits a plurality of lights L1 to L4 having a single wavelength at different timings via the second optical fibers 106 to 109. In this embodiment, the measuring light irradiation unit 103 includes a light source 100, a circulator 101, and an optical coupler 102.

[0089] The light source 100 is a light emitting device that emits light L having a single wavelength. The circulator 101 is a component that changes the traveling direction of the light L.

[0090] The optical coupler 102 branches the light L emitted from the light source 100 into a plurality of lights L1 to L4 having equal intensities, and guides the lights L1 to L4 to the plurality of second optical fibers 106 to 109 , respectively.

[0091] The second optical fibers 106 to 109 are used for measuring inclination and distance. The second optical fibers 106 to 109 are held by the optical fiber block 104. Furthermore, the second optical fibers 106 to 109 have different optical path lengths. In this embodiment, the lengths of the second optical fibers 106, 107, 108, and 109 increase in order. Light L1 to L4 branched by the optical coupler 102 is guided through the second optical fibers 106 to 109 of different lengths, thereby being emitted at different timings.

[0092] The optical fiber block 104 is a component that holds the emission-side ends of the first optical fiber 105 and the second optical fibers 106 to 109. The first optical fiber 105 and the second optical fibers 106 to 109 are arranged in the optical fiber block 104 so that their emission end faces are flush with the block end face 30. Figure 2 As shown, the optical fiber block 104 includes a holder 41 and a cover 42. The holder 41 is formed with a groove in which the first optical fiber 105 is disposed. The cover 42 serves as a cover for the holder 41. By bringing the cover 42 into contact with the groove-forming surface of the holder 41, the contact surface between the groove of the holder 41 and the cover 42 forms an insertion hole 50 in the center portion of the optical fiber block 104 for holding the first optical fiber 105.

[0093] Furthermore, insertion holes 51 to 54 are formed at four corners of the optical fiber block 104. Three of the insertion holes 51 to 54 are in a positional relationship where a plurality of lines connected to each other form a triangle.

[0094] The second optical fibers 106 to 109 are respectively inserted into the insertion holes 51 to 54. Thus, the second optical fibers 106 to 109 are arranged so that lines connecting three of the emission end faces of the second optical fibers 106 to 109 form a triangle.

[0095] By arranging the second optical fibers 106 to 109 in this manner, the inclination of the block end face 30 of the optical fiber block 104 relative to the substrate end face 130 of the optical substrate 120 can be measured around two mutually orthogonal axes.

[0096] The light detection unit 110 receives reflected light beams RL1-RL4 of the plurality of light beams L1-L4 reflected from the substrate end face 130 of the optical substrate 120 via the second optical fibers 106-109 and detects the intensities of the reflected light beams RL1-RL4. The light detection unit 110 outputs the detection results to the calculation unit 111. Furthermore, after being guided by the second optical fibers 106-109, the plurality of reflected light beams RL1-RL4 are redirected by the circulator 101 and directed to the light detection unit 110.

[0097] The calculation unit 111 is a computer with computing capabilities. It functions as the inclination calculation unit 112 and the distance calculation unit 113. The calculation unit 111 outputs the calculation results to the adjustment device 114. For example, the computer includes a processor and a memory connected to the processor. The memory stores a program containing multiple instructions for performing inclination and distance calculations. When the processor executes the program, the computer functions as the inclination calculation unit 112 and the distance calculation unit 113.

[0098] The inclination calculation unit 112 calculates the inclination of the block end face 30 of the optical fiber block 104 relative to the substrate end face 130 of the optical substrate 120 based on the detection result obtained by the light detection unit 110. The distance calculation unit 113 calculates the end-to-end distance between the substrate end face 130 of the optical substrate 120 and the block end face 30 of the optical fiber block 104 based on the detection result obtained by the light detection unit 110.

[0099] The adjustment device 114 includes a drive device (e.g., an actuator) that holds the optical fiber block 104 and functions as a tilt adjustment unit 115 and a distance adjustment unit 116. The tilt adjustment unit 115 adjusts the relative posture of the optical fiber block 104 with respect to the optical substrate 120 based on the calculated tilt. The distance adjustment unit 116 adjusts the relative distance of the optical fiber block 104 with respect to the optical substrate 120 based on the calculated end-face distance.

[0100] When the first optical fiber 105 is connected to the optical substrate 120, the optical adjustment device 10 is used to perform optical adjustment of the first optical fiber 105. In this specification, optical adjustment refers to adjusting the relative posture and position of the block end face 30 of the optical fiber block 104 with respect to the substrate end face 130 of the optical substrate 120. Figure 3 1 is a flowchart showing the procedure of optical adjustment performed by the optical adjustment device 10 according to the embodiment. Figure 3 The optical adjustment method using the optical adjustment device 10 shown includes a relative posture adjustment process based on steps S1 to S5 and a relative distance adjustment process based on steps S6 to S10 .

[0101] During optical adjustment, the first optical fiber 105 and the second optical fibers 106 to 109 are mounted on the optical fiber block 104 of the optical adjustment device 10. The optical fiber block 104, holding the first optical fiber 105 and the second optical fibers 106 to 109, is then positioned so that the block end face 30 of the optical fiber block 104 and the substrate end face 130 of the optical substrate 120 are reliably separated from each other to a degree that they do not contact each other. This separation distance is, for example, 20 μm.

[0102] With the optical fiber block 104 and optical base 120 installed as described above, the optical adjustment device 10 performs a light detection operation (step S1). In step S1, the light source 100 emits light L. Light L passes through the circulator 101 and is branched into multiple light beams L1 to L4 by the optical coupler 102. Light beams L1 to L4 are emitted from the emission end faces of the second optical fibers 106 to 109 toward the substrate end face 130 of the optical base 120.

[0103] Since the optical path lengths of the lights L1 to L4 from incident to emitted from the second optical fibers 106 to 109 are different, the lights L1 to L4 are emitted at different timings. In this embodiment, the lights L1, L2, L3, and L4 are emitted in this order.

[0104] The emitted light beams L1 to L4 are reflected by the substrate end face 130 of the optical substrate 120. Furthermore, each reflected light beam RL1 to RL4 is received by the second optical fibers 106 to 109 and detected by the light detection unit 110 via the second optical fibers 106 to 109, the optical coupler 102, and the circulator 101. Due to the differences in the lengths of the second optical fibers 106 to 109, the reflected light beams RL1 to RL4 are detected at different timings. In this embodiment, the reflected light beams RL1, RL2, RL3, and RL4 are detected in this order.

[0105] Figure 4 1 is a diagram showing an example of the detection results of the reflected lights RL1 to RL4 obtained by the light detection unit 110. The vertical axis represents light intensity, and the horizontal axis represents time. Time tb represents the time when the light source 100 emits light L.

[0106] Figure 4 Peaks P1 to P4 correspond to reflected light beams RL1 to RL4, respectively. The time from time tb to peaks P1 to P4 is Δt1 to Δt4, respectively. Depending on the length of the second optical fibers 106 to 109, Δt1 < Δt2 < Δt3 < Δt4 is achieved. Peaks P1 to P4 have a temporal width. The reason for this is explained below.

[0107] Figure 5 The diagram shows how the light beams L1 and L2 emitted from the second optical fibers 106 and 107 are reflected by the substrate end surface 130 of the optical substrate 120 and return to the second optical fibers 106 and 107 as reflected light beams RL1 and RL2 .

[0108] Figure 5 The intensity spectra D11~D14 are respectively the intensity spectrum of the light L1 emitted from the second optical fiber 106, the intensity spectrum of the light L1 incident on the optical substrate 120, the intensity spectrum of the reflected light RL1 just after the light L1 is reflected by the optical substrate 120, and the intensity spectrum of the reflected light RL1 incident on the second optical fiber 106.

[0109] Figure 5 The intensity spectra D21~D24 are respectively the intensity spectrum of the light L2 emitted from the second optical fiber 107, the intensity spectrum of the light L2 incident on the optical substrate 120, the intensity spectrum of the reflected light RL2 just after the light L2 is reflected by the optical substrate 120, and the intensity spectrum of the reflected light RL2 incident on the second optical fiber 107.

[0110] The light L1 to L4 emitted from the second optical fibers 106 to 109 has a spread angle relative to the numerical aperture of the second optical fibers 106 to 109. Figure 5 As shown, relative to the optical axis of the light emitted from the central part of the second optical fiber 106, 107 (hereinafter sometimes also referred to as the "central light"), the optical axis of the light emitted from the peripheral part of the second optical fiber 106, 107 (hereinafter sometimes also referred to as the "peripheral light") is inclined toward the peripheral side.

[0111] For example, when the block end face 30 of the optical fiber block 104 is parallel to the substrate end face 130 of the optical substrate 120, the central light is incident perpendicularly to the substrate end face 130 of the optical substrate 120 and is reflected. In contrast, the peripheral light is incident at an angle relative to the substrate end face 130 of the optical substrate 120 and is reflected in a direction corresponding to the angle of incidence. Consequently, a difference occurs in the optical path lengths of the central light and the peripheral light from the time light L1 is emitted from the second optical fiber 106 to the time reflected light RL1 is received. Consequently, reflected light RL1 based on the peripheral light returns to the second optical fiber 106 later than reflected light RL1 based on the central light.

[0112] Thus, even if the reflected light RL1 is the same, the detection timing will differ depending on the emission position (central portion, peripheral portion, etc.) of the light L1 in the emission end face of the second optical fiber 106. Figure 4 As shown, time widths occur in peaks P1 to P4.

[0113] As mentioned above, in Figure 3 After performing the light detection operation in step S1, the light detection unit 110 outputs the detection results of the reflected lights RL1 to RL4 to the calculation unit 111 (step S2). Figure 4 The data shown shows a temporal change in light intensity with a plurality of peaks corresponding to the reflected lights RL1 to RL4.

[0114] Next, the inclination calculation unit 112 calculates the inclination of the block end face 30 of the optical fiber block 104 relative to the substrate end face 130 of the optical substrate 120 based on the detection result of the light detection unit 110, and outputs the calculated inclination to the inclination adjustment unit 115 (step S3).

[0115] The following description uses the calculation of the inclination θy about the y-axis in step S3 as an example. In the description of this embodiment, it is assumed that when the block end face 30 of the optical fiber block 104 is parallel to the substrate end face 130 of the optical substrate 120, the inclination θx about the x-axis and the inclination θy about the y-axis are both 0 degrees.

[0116] Figure 6 It shows that the second optical fibers 106, 107 and the optical fiber block 104 are in Figure 5 A graph showing the temporal change in the detected light intensity in the illustrated state. Figure 6 Δt11 and Δt21 are times from the time tb at which the light source 100 emits the light L to the time at which the light detection unit 110 starts detecting the reflected light RL1 and the reflected light RL2 .

[0117] The temporal cumulative values AC1 and AC2 of peaks P1 and P2 differ from each other. Furthermore, the time widths W1 and W2 of peaks P1 and P2 also differ from each other. The reasons for this are explained below. Time widths W1 and W2 are the time from the moment the light intensity reaches its maximum in peaks P1 and P2 to the moment the light intensity reaches its latest peak.

[0118] like Figure 5As shown, when the block end face 30 of the optical fiber block 104 is tilted at a given angle relative to the substrate end face 130 of the optical substrate 120, the light beams L1 and L2 are incident at an angle relative to the substrate end face 130 of the optical substrate 120. Furthermore, the reflected light beams RL1 and RL2 travel in directions corresponding to the angle of incidence of the light beams L1 and L2 on the substrate end face 130. Therefore, a portion of the reflected light beams RL1 and RL2 does not return to the second optical fibers 106 and 107. Consequently, the second optical fibers 106 and 107 are unable to receive a portion of the reflected light beams RL1 and RL2.

[0119] Specifically, when the block end face 30 of the optical fiber block 104 is tilted relative to the substrate end face 130 of the optical substrate 120 , the inter-end face distances between the emission end faces of the second optical fibers 106 and 107 and the substrate end face 130 of the optical substrate 120 are different.

[0120] like Figure 5 As shown, the longer the distance between the end faces (in Figure 5 The larger the number of reflected lights RL1 and RL2 reaching the second optical fibers 106 and 107, the greater the deviation of the arrival position of the reflected lights RL1 and RL2 from the center of the second optical fibers 106 and 107. Therefore, there is also a difference in the light amount of the reflected lights RL1 and RL2 reaching the second optical fibers 106 and 107 (the shaded areas of the intensity spectra D14 and D24).

[0121] The results, such as Figure 6 As shown, the longer the distance between the end faces, the smaller the integrated values AC1 and AC2 of the peaks P1 and P2 in the temporal variation of the light intensity.

[0122] Furthermore, as the distance between the end faces increases, more peripheral light is not received, resulting in earlier convergence of light intensity peaks P1 and P2, and shorter time widths W1 and W2 after the peaks P1 and P2 reach their maximum values. Time widths W1 and W2 correspond to the time from the moment the central light corresponding to peaks P1 and P2 enters the entire peak width to the moment the peripheral light that enters after the central light enters.

[0123] The inclination calculation unit 112 calculates and compares the integrated values AC1 and AC2 of the peaks P1 and P2 based on the temporal variation in the intensity of the reflected lights RL1 and RL2. Furthermore, the inclination calculation unit 112 calculates and compares the integrated values AC3 and AC4 of the peaks P3 and P4 based on the temporal variation in the intensity of the reflected lights RL3 and RL4.

[0124] The slope calculation unit 112 calculates and compares the time widths W1 and W2 of the peaks P1 and P2 corresponding to the reflected lights RL1 and RL2. The slope calculation unit 112 also calculates and compares the time widths W3 and W4 of the peaks P3 and P4 corresponding to the reflected lights RL3 and RL4.

[0125] The inclination calculation unit 112 calculates the inclination θy of the block end face 30 of the optical fiber block 104 relative to the substrate end face 130 of the optical substrate 120 around the y-axis based on the comparison results of (A1), (A2), (A3), and (A4).

[0126] (A1) Comparison results of cumulative values AC1 and AC2

[0127] (A2) Comparison results of cumulative values AC3 and AC4

[0128] (A3) Comparison results of time width W1 and time width W2

[0129] (A4) Comparison results of time width W3 and time width W4

[0130] Furthermore, the inclination calculation unit 112 calculates the inclination θx of the block end face 30 of the optical fiber block 104 relative to the substrate end face 130 of the optical substrate 120 around the x-axis based on the comparison results of (B1), (B2), (B3), and (B4) below.

[0131] (B1) Comparison results of cumulative values AC1 and AC3

[0132] (B2) Comparison results of cumulative values AC2 and AC4

[0133] (B3) Comparison results of time width W1 and time width W3

[0134] (B4) Comparison results of time width W2 and time width W4

[0135] Figure 7 It is a diagram showing the correspondence between the comparison results of the above-mentioned (A1), (A2), (A3) and (A4) and (B1), (B2), (B3) and (B4) and the inclinations θx and θy.

[0136] When the integrated values AC1 and AC3 are equal, the integrated values AC2 and AC4 are equal, the time widths W1 and W3 are equal, and the time widths W2 and W4 are equal, the inclination θx can be determined to be zero.

[0137] When the cumulative value AC1 is greater than the cumulative value AC3, the cumulative value AC2 is greater than the cumulative value AC4, the time width W1 is greater than the time width W3, and the time width W2 is greater than the time width W4, the inclination θx can be determined to be positive. A positive inclination θx means that the block end face 30 of the optical fiber block 104 is tilted so that the emission end faces of the second optical fibers 106 and 107 are closer to the block end face 30 of the optical substrate 120 than the emission end faces of the second optical fibers 108 and 109.

[0138] If the cumulative value AC1 is less than the cumulative value AC3, the cumulative value AC2 is less than the cumulative value AC4, the time width W1 is less than the time width W3, and the time width W2 is less than the time width W4, the inclination θx can be determined to be negative. A negative inclination θx means that the block end face 30 of the optical fiber block 104 is tilted so that the emission end faces of the second optical fibers 106 and 107 are further away from the substrate end face 130 of the optical substrate 120 than the emission end faces of the second optical fibers 108 and 109.

[0139] When the integrated values AC1 and AC2 are equal, the integrated values AC3 and AC4 are equal, the time widths W1 and W2 are equal, and the time widths W3 and W4 are equal, it can be determined that the inclination θy is zero.

[0140] When the cumulative value AC1 is greater than the cumulative value AC2, the cumulative value AC3 is greater than the cumulative value AC4, the time width W1 is greater than the time width W2, and the time width W3 is greater than the time width W4, the inclination θy can be determined to be positive. A positive inclination θy means that the block end face 30 of the optical fiber block 104 is tilted so that the emission end faces of the second optical fibers 106 and 108 are closer to the substrate end face 130 of the optical substrate 120 than the emission end faces of the second optical fibers 107 and 109.

[0141] If the cumulative value AC1 is smaller than the cumulative value AC2, the cumulative value AC3 is smaller than the cumulative value AC4, the time width W1 is smaller than the time width W2, and the time width W3 is smaller than the time width W4, the inclination θy can be determined to be negative. A negative inclination θy means that the block end face 30 of the optical fiber block 104 is tilted so that the emission end faces of the second optical fibers 106 and 108 are further away from the substrate end face 130 of the optical substrate 120 than the emission end faces of the second optical fibers 107 and 109.

[0142] exist Figure 3 After calculating the inclinations θx and θy in step S3 , the inclination adjustment unit 115 determines whether any one of the calculated inclinations θx and θy is less than or equal to a predetermined angle (step S4 ).

[0143] If at least one of the inclinations θx and θy is greater than a predetermined angle ("No" in step S4), the inclination adjustment unit 115 adjusts the relative posture of the optical fiber block 104 with respect to the substrate end surface 130 of the optical substrate 120 based on the calculated inclinations θx and θy (step S5). Specifically, in step S5, the inclination adjustment unit 115 rotates the optical fiber block 104 about the x-axis and about the y-axis so that the inclinations θx and θy approach zero.

[0144] Until the inclinations θx and θy are both below the given angle, that is, until the block end face 30 of the optical fiber block 104 can be considered parallel to the substrate end face 130 of the optical substrate 120, steps S1 to S5 are executed to adjust the inclination (posture) of the optical fiber block 104 relative to the optical substrate 120.

[0145] When the inclinations θx and θy are both smaller than a given angle (Yes in step S4 ), the distance between the block end face 30 of the optical fiber block 104 and the substrate end face of the optical substrate 120 is adjusted through the processing after step S6 .

[0146] First, the distance adjuster 116 moves the optical fiber block 104 by a predetermined set distance so as to bring the optical fiber block 104 closer to the optical base 120 (step S6 ).

[0147] Hereinafter, the position of the optical fiber block 104 before the movement in step S6 is referred to as a first position, and the position of the optical fiber block 104 after moving a set distance from the first position is referred to as a second position.

[0148] Next, the optical adjustment device 10 performs a light detection operation (step S7). The process of step S7 is the same as the process of step S1.

[0149] Next, the light detection unit 110 outputs the detection results of the reflected lights RL1 to RL4 to the calculation unit 111 (step S8). The process of step S8 is the same as the process of step S2.

[0150] Next, the distance calculator 113 calculates the distance between the substrate end face 130 of the optical substrate 120 and the block end face 30 of the optical fiber block 104 based on the detection result of the light detector 110, and outputs the calculated distance to the distance adjuster 116 (step S9).

[0151] Specifically, the distance calculator 113 compares the temporal change in the intensity of the reflected light RL1 when the optical fiber block 104 is located at the first position with the temporal change in the intensity of the reflected light RL1 when the optical fiber block 104 is located at the second position.

[0152] FIG. gA is a diagram showing an example of a detection result of the reflected light RL1 obtained by the light detection unit 110 when the optical fiber block 104 is located at the first position. Figure 8B 1 is a diagram showing an example of a detection result of the reflected light RL1 obtained by the light detection unit 110 when the optical fiber block 104 is located at the second position.

[0153] Figure 8A Δt11 and Figure 8BΔt12 is the time from time tb when the light source 100 emits the light L to when the light detection unit 110 starts detecting the reflected light RL1 , and is the time indicating the positions of the peaks P11 and P12 in the temporal variation of the intensity of the reflected light RL1 .

[0154] like Figure 8A 、 Figure 8B As shown, time Δt11 is greater than time Δt12. Maximum intensity I11 of peak P11 is less than maximum intensity I12 of peak P12. Furthermore, temporal cumulative value AC111 of peak P11 is less than temporal cumulative value AC112 of peak P12.

[0155] The reason why the time Δt11 is longer than the time Δt12 is that the optical path length of the reflected light RL1 when the optical fiber block 104 is at the first position is longer than the optical path length of the reflected light RL1 when the optical fiber block 104 is at the second position.

[0156] The reason why the cumulative value AC111 is smaller than the cumulative value AC112 will be described below.

[0157] Figure 9A 、 Figure 9B This diagram shows how light L1 emitted from the second optical fiber 106 is reflected by the substrate end face 130 of the optical substrate 120 and returns to the second optical fiber 106 as reflected light RL1 . Figure 9A 、 Figure 9B States where the optical fiber block 104 is located at the first position and the second position are shown respectively.

[0158] As described above, the light L1 emitted from the second optical fiber 106 has a spread angle relative to the numerical aperture of the second optical fiber 106. Therefore, the optical axis of the peripheral light is tilted toward the outer periphery relative to the optical axis of the central light. Consequently, the area illuminated by the reflected light RL1 upon reaching the block end face 30 of the optical fiber block 104 is spread wider than the emission end face of the second optical fiber 106. Consequently, the reflected light RL1 that reaches the outer side of the emission end face of the second optical fiber 106 cannot be received by the second optical fiber 106.

[0159] like Figure 9A 、 Figure 9B As shown, the closer the block end face 30 of the optical fiber block 104 (the emission end face of the second optical fiber 106) is to the substrate end face 130 of the optical substrate 120, the smaller the difference between the irradiation area of the reflected light RL1 and the emission end face of the second optical fiber 106. As a result, the amount of reflected light RL1 received by the second optical fiber 106 increases, and the amount of light detected by the light detection unit 110 also increases.

[0160] Due to the above reasons, the accumulated value AC111 is smaller than the accumulated value AC112.

[0161] Furthermore, the closer the emission end face of the second optical fiber 106 is to the substrate end face 130 of the optical substrate 120, the less likely the light L1 is to be broadened, and the less likely it is that a difference in arrival time between the reflected light based on the central light and the reflected light based on the peripheral light will occur with respect to the second optical fiber 106. Therefore, the peak width of the peak P11 is greater than the peak width of the peak P12.

[0162] In this way, the inter-end face distance between the substrate end face 130 of the optical substrate 120 and the block end face 30 of the optical fiber block 104 can be calculated based on the difference between the integrated value AC111 and the integrated value AC112 and the difference between the time Δt11 and the time Δt12.

[0163] exist Figure 3 After calculating the distance between the end faces in step S9, the distance adjustment unit 116 determines whether the calculated distance between the end faces is less than a given distance (step S10). If the calculated distance between the end faces is greater than the given distance (No in step S10), the distance adjustment unit 116 adjusts the relative position of the block end face 30 of the optical fiber block 104 with respect to the substrate end face 130 of the optical substrate 120 based on the calculated distance between the end faces (step S11). Specifically, the distance adjustment unit 116 brings the optical fiber block 104 closer to the optical substrate 120 than the second position. Thereafter, the processing of steps S7 to S10 is performed until the distance between the block end face 30 of the optical fiber block 104 and the substrate end face 130 of the optical substrate 120 becomes less than the given distance.

[0164] When steps S7 to S10 are executed again, the position of the optical fiber block 104 before the movement is set as the first position and the position after the movement is set as the second position, and the end face distance is calculated based on the detection results of the reflected light RL1 at each position.

[0165] When the calculated distance between end faces is equal to or smaller than a predetermined distance (YES in step S10 ), the optical adjustment device 10 ends the optical adjustment operation.

[0166] After the above-described optical adjustment, the position of the optical fiber block 104 in the xy plane is adjusted so that the intensity of light propagating through the waveguide 121 of the optical base 120 is maximized. This adjustment, along with the above-described optical adjustment, allows the optical axis of the first optical fiber 105 to be appropriately aligned with respect to the waveguide 121 of the optical base 120.

[0167] In the above description, Figure 3In step S3, the inclination of the block end face 30 relative to the substrate end face 130 is calculated based on the time width from the time when the light intensity reaches its maximum value to the time when the peak reaches its latest end. However, the calculation method described above need not be used as long as the calculation method is based on the peak width, which includes the time width from the time when the light intensity reaches its maximum value to the time when the peak reaches its latest end. For example, the inclination may be calculated based on the time width (total peak width) from the time when peaks P1 to P4 reach their earliest end to the time when they reach their latest end.

[0168] In addition, Figure 3 In step S9, other times may be used as the times indicating the positions of peaks P11 and P12 corresponding to reflected light RL1, instead of the times Δt11 and Δt12 from the time tb when light source 100 emits light L to the time when light detection unit 110 starts detecting reflected light RL1. For example, the time from the time tb when light source 100 emits light L to the time when peaks P11 and P12 show their maximum intensities may be used.

[0169] <Optical Device 210>

[0170] Figure 10 This figure shows an optical device 210 according to this embodiment. Optical device 210 includes a first optical fiber 105, an optical base 120, and an optical fiber block 104. The optical fiber block 104, which holds the first optical fiber 105 and second optical fibers 106 to 109 for measurement, is connected to the optical base 120 in a positioned state, thereby forming optical device 210.

[0171] In the optical device 210, the optical fiber block 104 and the optical substrate 120 are bonded together by the adhesive layer 220, and their relative positional relationship is maintained. The first optical fiber 105 is optically connected to the waveguide 121 of the optical substrate 120. Figure 10 In the embodiment, the optical fiber block 104 holds the second optical fibers 106 to 109. However, after the optical properties of the first optical fiber 105 are adjusted, it is not necessary to hold the second optical fibers 106 to 109. When the optical fiber block 104 holds the second optical fibers 106 to 109, the second optical fibers 106 to 109 are inserted into the insertion holes 51 to 54, respectively.

[0172] The adhesive layer 220 is a layer that fixes the optical fiber block 104 to the substrate end surface 130 of the optical substrate 120 .

[0173] The following describes a process for forming the optical device 210 .

[0174] First, the relative posture and distance of the first optical fiber 105 to the optical base 120 are adjusted (optical adjustment operation) using the optical adjustment device 10. This allows the relative posture and distance of the optical fiber block 104 to the optical base 120 to be appropriately adjusted.

[0175] Next, the position of the optical fiber block 104 in the xy plane is adjusted to maximize the intensity of light propagating through the waveguide 121 of the optical base 120. This adjustment and the aforementioned optical adjustment process allow the optical axis of the first optical fiber 105 to be appropriately aligned with respect to the waveguide 121 of the optical base 120.

[0176] Next, an adhesive layer 220 is formed to fix the optical fiber block 104 to the optical substrate 120. At this time, the optical fiber block 104 and the optical substrate 120 are physically connected by applying an adhesive, and the adhesive is cured to form the adhesive layer 220. As the adhesive, an adhesive with an adjusted refractive index for light is used. In addition, Figure 10 The adhesive layer 220 bonds the side surface of the optical fiber block 104 and the substrate end surface 130 of the optical substrate 120 , but the block end surface 30 of the optical fiber block 104 and the substrate end surface 130 of the optical substrate 120 may also be connected.

[0177] Then, the second optical fibers 106 to 109 are cut shorter as necessary. Alternatively, the second optical fibers 106 to 109 are removed from the optical fiber block 104 .

[0178] The optical device 210 is formed through the above process.

[0179] The optical adjustment device 10 of this embodiment is an optical adjustment device 10 used when connecting the first optical fiber 105 to the optical substrate 120 of the connection target, and comprises: a measuring light irradiation unit 103, which has a plurality of second optical fibers 106 to 109, and emits a plurality of lights L1 to L4 having a single wavelength at different timings through the plurality of second optical fibers 106 to 109; an optical fiber block 104, which holds the emission side ends of the first optical fiber 105 and the plurality of second optical fibers 106 to 109; a light detection unit 110, which detects the light emitted by the optical substrate 120 via the plurality of second optical fibers 106 to 109. The multiple reflected lights RL1 to RL4 corresponding to the multiple lights L1 to L4 reflected by the substrate end face 130 of 120 are received and detected; the inclination calculation part 112 compares the time variation of the intensity of each of the multiple reflected lights RL1 to RL4 with each other, and calculates the inclination θx, θy of the optical fiber block 104 relative to the optical substrate 120 based on the comparison result; and the distance calculation part 113 calculates the distance between the end faces of the optical substrate 120 and the optical fiber block 104 based on the time variation of the intensity of at least one reflected light among the multiple reflected lights RL1 to RL4.

[0180] The optical adjustment device 10 measures the inclinations θx and θy of the first optical fiber 105 relative to the optical substrate 120 to which it is connected, and appropriately adjusts the inclinations θx and θy of the first optical fiber 105 based on the measured inclinations θx and θy, thereby enabling high-precision measurement of the end-face distance. Furthermore, the accuracy of optical axis adjustment of the first optical fiber 105 can be improved.

[0181] Furthermore, the optical adjustment device 10 can measure the distance between the end faces of the optical base 120 and the optical fiber block 104 with high precision, thereby preventing the waveguide 121 of the optical base 120 from contacting the first optical fiber 105 during optical axis adjustment.

[0182] The distance measuring device disclosed in Patent Document 1 requires a light source with a periodically varying wavelength. Furthermore, the distance measuring device requires a light receiver that detects the intensity of the periodically varying wavelength light. Furthermore, the distance measuring device requires a signal processing device capable of performing signal processing on the light receiver in synchronization with the wavelength variation of the light source. Thus, the use of the distance measuring device disclosed in Patent Document 1 results in increased functionality, complexity, and, consequently, size of the device.

[0183] The optical adjustment device 10 of this embodiment simply emits multiple light beams L1 to L4 at different timings toward the optical base 120 via the second optical fibers 106 to 109, and receives the reflected light beams RL1 to RL4 at different timings. This allows for inclination and distance measurement using a simple configuration, without requiring additional functionality, complexity, or size. Consequently, the inclination and distance measurement devices and the measurement process can be simplified and reduced in cost.

[0184] The plurality of second optical fibers 106 to 109 include three optical fibers 106 to 108 arranged so that lines connecting the emission end faces form a triangle. This allows measurement of inclinations θx and θy about two orthogonal axes (x and y).

[0185] The plurality of second optical fibers 106 to 109 have different optical path lengths, thereby making it easy to make the emission timings of the plurality of light beams L1 to L4 different from each other.

[0186] The measurement light irradiation unit 103 includes: a light source 100 that emits light having a single wavelength; and an optical coupler 102 that branches the light L emitted from the light source 100 into a plurality of lights L1 to L4 having equal intensities, and guides the plurality of lights L1 to L4 to a plurality of second optical fibers 106 to 109, respectively.

[0187] This eliminates the need for multiple light sources 100, and allows the light detection unit 110 to detect reflected lights RL1 to RL4 at different timings. Furthermore, the light source 100 does not need to emit light to the second optical fibers 106 to 109 at different time periods, allowing the detection of reflected lights RL1 to RL4 to be completed quickly.

[0188] The inclination calculation unit 112 calculates the inclination θx of the optical fiber block 104 relative to the optical base 120 about the x-axis (first axis) and the inclination θy about the y-axis (second axis) perpendicular to the x-axis (first axis).

[0189] This allows the block end face 30 of the optical fiber block 104 to be more reliably parallel to the substrate end face 130 of the optical substrate 120 .

[0190] When calculating the inclinations θx and θy, the inclination calculation unit 112 calculates the integrated values AC1 to AC4 of the peaks P1 to P4 corresponding to the reflected lights RL1 to RL4 , respectively, based on the temporal variation of the intensity of the reflected lights RL1 to RL4 , and compares the integrated values AC1 to AC4 .

[0191] Furthermore, the inclination calculation unit 112 compares the peak widths of the plurality of peaks P1 to P4 corresponding to the reflected lights RL1 to RL4 , respectively.

[0192] Then, the inclination adjusting unit 115 adjusts the relative posture of the optical fiber block 104 with respect to the optical base 120 based on the calculated inclinations θx and θy.

[0193] Furthermore, the optical adjustment device 10 further includes a distance adjustment unit 116 that adjusts the relative distance between the optical fiber block 104 and the optical base 120 .

[0194] When calculating the distance between the end faces, the distance calculator 113 calculates the distance between the end faces of the optical substrate 120 and the optical fiber block 104 based on the difference between the integrated values AC111 and AC112 of the intensity of the reflected light RL1 when the optical fiber block 104 is located at different positions.

[0195] Furthermore, the distance calculator 113 calculates the distance between the end faces of the optical substrate 120 and the optical fiber block 104 based on times Δt11 and Δt12 indicating the peak positions of the reflected light RL1 when the optical fiber block 104 is located at different positions.

[0196] The optical device 210 according to this embodiment includes: a first optical fiber 105; an optical substrate 120 having a waveguide and being connected to the first optical fiber 105; and an optical fiber block 104 fixed to the optical substrate 120. The optical device 210 is formed using the aforementioned optical adjustment method, so that the optical fiber block 104 not only holds the first optical fiber 105 but also has insertion holes 51 to 54 formed by a plurality of interconnected lines forming a triangle.

[0197] Furthermore, as described above, the optical device 210 may include the second optical fibers 106 to 109 inserted into the insertion holes 51 to 54 .

[0198] In the embodiment, the optical adjustment device 10 is described by taking the connection between the first optical fiber 105 and the waveguide 121 of the optical substrate 120 as an example, but the present invention is also applicable to the connection between the first optical fiber 105 and other optical fibers held by the substrate.

[0199] (Variation)

[0200] The optical adjustment device 10 may not include the optical coupler 102. In this case, the second optical fibers 106 to 109 are each connected to the light source 100. Furthermore, the second optical fibers 106 to 109 may have the same length. In this case, the light source 100 emits light L1 to L4 into the second optical fibers 106 to 109 at different timings.

[0201] The optical fiber block 104 only needs to include three second optical fibers arranged so that at least a plurality of lines connecting the emission end faces to each other form a triangle.

[0202] exist Figure 3 In step S3, the inclination about the y-axis may be calculated based only on (A1) and (A2), or based only on (A3) and (A4). Furthermore, the inclination about the x-axis may be calculated based only on (B1) and (B2), or based only on (B3) and (B4).

[0203] exist Figure 3 In step S9, the detection results of the reflected lights detected via the same second optical fiber can be compared. That is, the detection results of the reflected lights RL2 to RL4 detected via second optical fibers 107 to 109 other than second optical fiber 106 can also be compared. Furthermore, the end-face distances can be calculated based on the detection results of the plurality of reflected lights RL1 to RL4 and the average of the calculated end-face distances can be taken.

[0204] In step S9 , the distance between end faces may be calculated based on only the comparison result between the integrated values of the peaks, or the distance may be calculated based on only the comparison result between the times indicating the positions of the peaks.

[0205] According to the present disclosure, it is possible to provide an optical adjustment apparatus, an optical adjustment method, and an optical device capable of measuring the distance of an optical fiber with respect to an optical substrate to which it is connected with high precision.

[0206] Industrial applicability

[0207] The present disclosure can be suitably used in an optical adjustment apparatus, an optical adjustment method, and an optical device for measuring the inclination and distance of an optical fiber relative to an optical substrate to which it is connected.

Claims

1. An optical adjustment device used when connecting a first optical fiber to an optical substrate as a connection destination, comprising: a measurement light irradiation unit including a plurality of second optical fibers for emitting a plurality of lights having a single wavelength at mutually different timings through the plurality of second optical fibers; an optical fiber block for holding the emission-side ends of the first optical fiber and the plurality of second optical fibers; a light detecting unit that receives and detects a plurality of reflected lights corresponding to the plurality of lights reflected from the substrate end surface of the optical substrate via the plurality of second optical fibers; an inclination calculation unit that compares temporal changes in the intensity of each of the plurality of reflected lights with one another and calculates an inclination of the optical fiber block relative to the optical substrate based on the comparison result; and The distance calculation unit calculates the distance between the end faces of the optical substrate and the optical fiber block based on a temporal change in the intensity of at least one reflected light among the plurality of reflected lights.

2. The optical adjustment device according to claim 1, wherein: The plurality of second optical fibers include three optical fibers arranged so that a plurality of lines connecting the emission end faces to each other form a triangle.

3. The optical adjustment device according to claim 2, wherein: The plurality of second optical fibers have different optical path lengths from one another.

4. The optical adjustment device according to claim 3, wherein: The measuring light irradiation unit includes: a light source emitting light having a single wavelength; and The optical coupler branches the light emitted from the light source into the plurality of lights having equal intensities, and guides the plurality of lights to the plurality of second optical fibers, respectively.

5. The optical adjustment device according to claim 3 or 4, wherein: The inclination calculation unit calculates an inclination θx of the optical fiber block relative to the optical base around a first axis and an inclination θy of the optical fiber block relative to the optical base around a second axis perpendicular to the first axis.

6. The optical adjustment device according to any one of claims 1 to 4, wherein: The inclination calculation unit calculates a plurality of integrated values of intensities respectively corresponding to the plurality of reflected lights based on a temporal change in the intensity of each of the plurality of reflected lights, and compares the integrated values of the plurality of intensities with one another.

7. The optical adjustment device according to any one of claims 1 to 4, wherein: The inclination calculation unit compares a plurality of peak widths corresponding to the plurality of reflected lights, respectively, in a temporal change in intensity of each of the plurality of reflected lights.

8. The optical adjustment device according to any one of claims 1 to 4, wherein: The optical fiber block further includes an inclination adjustment unit configured to adjust a relative posture of the optical fiber block with respect to the optical base based on the calculated inclination.

9. The optical adjustment device according to any one of claims 1 to 4, wherein: The optical fiber block is further provided with a distance adjusting unit for adjusting a relative distance between the optical fiber block and the optical substrate.

10. The optical adjustment device according to any one of claims 1 to 4, wherein: The distance calculation unit calculates the distance between the end faces of the optical substrate and the optical fiber block based on a difference in integrated values of the intensity of the reflected light when the optical fiber block is located at different positions.

11. The optical adjustment device according to any one of claims 1 to 4, wherein: The distance calculation unit calculates the distance between the end faces of the optical substrate and the optical fiber block based on a time indicating a peak position in a temporal change in the intensity of the reflected light when the optical fiber block is located at different positions.

12. An optical adjustment method, which is performed when connecting a first optical fiber to an optical substrate of a connection destination, wherein: The optical fiber block holds the emission-side ends of the first optical fiber and a plurality of second optical fibers for measurement. emitting a plurality of lights having a single wavelength at mutually different timings via the plurality of second optical fibers, receiving and detecting a plurality of reflected lights corresponding to the plurality of lights reflected from the substrate end surface of the optical substrate via the plurality of second optical fibers, comparing temporal changes in intensity of each of the plurality of reflected lights with each other, and calculating an inclination of the optical fiber block relative to the optical substrate based on the comparison result, The distance between the end faces of the optical substrate and the optical fiber block is calculated based on a temporal change in the intensity of at least one reflected light among the plurality of reflected lights.

13. The optical adjustment method according to claim 12, wherein: adjusting the relative posture of the optical fiber block with respect to the optical substrate based on the calculated inclination, The relative position of the optical fiber block with respect to the optical substrate is adjusted based on the calculated distance between the end faces.

14. An optical device comprising: 1st optical fiber; an optical substrate having a waveguide and being a connection destination of the first optical fiber; and an optical fiber block fixed to the optical substrate, The optical fiber block holds the first optical fiber and has a plurality of insertion holes formed by a plurality of mutually connected lines forming a triangle. The relative posture and relative distance of the first optical fiber with respect to the optical substrate are adjusted using the optical adjustment device according to any one of claims 1 to 11.

15. The optical device according to claim 14, wherein The optical fiber further includes a plurality of second optical fibers inserted through the plurality of insertion holes.

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