JP2015055788A - Optical transmission line alignment method, optical transmission line alignment apparatus, and optical transmission line alignment program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of performing optical transmission line alignment based on passive regulation at low cost with high accuracy.SOLUTION: An optical transmission line alignment method includes: acquiring a relative position of a second optical transmission line 25 to a first optical transmission line 12 on camera coordinates while observing a joint position between the first optical transmission line 12 and the second optical transmission line 25 within the same visual field by means of a camera 40 arranged obliquely upward of the joint position between the first optical transmission line 12 and the second optical transmission line 25; acquiring an end surface distance d between the first optical transmission line 12 and the second optical transmission line 25 at the joint position; calculating a deviation amount between the relative position on the camera coordinates and an actual relative position on the basis of the end surface distance d and a camera observation angle φ; and calculating the actual relative position of the second optical transmission line 25 to the first optical transmission line 12 from the relative position on the camera coordinates and the deviation amount, and determining an alignment amount for the first optical transmission line 12 and the second optical transmission line 25.

Description

  The present invention relates to an optical transmission line alignment technique.

  In order to transmit and receive optical signals, an optical module in which optical elements such as a laser diode and a photodiode are integrated is used. Some optical modules have optical waveguides and optical fibers joined together. However, with the recent development of wavelength multiplexing technology and the like, input / output of optical signals in a plurality of channels is required. As a multi-channel optical transmission line, an optical fiber array in which optical fibers are arranged at equal intervals in a glass block is used. For joining the optical fiber array and the optical waveguide, the optical fiber array is generally aligned with the end face of the optical waveguide chip and fixed with an adhesive.

  In order to reduce the size of the optical module, it is necessary to reduce or increase the density of the optical waveguide chip. For this purpose, the optical waveguide core is reduced to reduce the minimum bending radius. When an optical fiber or an optical waveguide is joined, as the core (mode field diameter) becomes smaller, the rate of increase in coupling loss with respect to positional deviation, in particular, optical axis deviation increases. With miniaturization, the allowable range of misalignment of the optical fiber with respect to the optical waveguide is becoming narrower, and at present, alignment accuracy of 1 μm or less is required.

  As an alignment generally performed, there is an adjustment method called active adjustment. Active adjustment is a method in which light is input and output and alignment is performed based on a power measurement value. For example, when an optical fiber array is bonded to one side of an optical waveguide chip, alignment is performed while driving a laser diode or photodiode on the optical waveguide and monitoring the optical power via the optical fiber array. When joining an optical fiber array to both sides of an optical waveguide, a laser light source is connected to one optical fiber array, and a power meter is connected to the other optical fiber array, and alignment is performed while monitoring power fluctuations. Since the position where the power is maximized is selected, high alignment accuracy can be obtained.

  However, active adjustment requires electrical connection to drive the laser diode and photodiode on the optical waveguide (in the case of single-sided junction), and requires a separate laser light source and power meter (in the case of double-sided junction). ) And other restrictions on the device are large.

  On the other hand, a method that does not use the power when light is input / output as a reference is called passive adjustment. For example, as shown in FIG. 1, the core position of the optical waveguide 112 of the optical waveguide chip 110 and the core position of the optical fiber 122 of the optical fiber array 120 are recognized using two cameras 141 and 142, respectively. The optical fiber array 120 and the optical waveguide chip 110 are relatively moved and aligned according to the position on the spatial coordinates.

  The passive adjustment method generally has low alignment accuracy. In order to achieve the same alignment accuracy as that of active adjustment, a control stage with high repeatability positioning accuracy incorporating a precision linear scale such as a glass scale is required. Passive adjustment is very limited in accuracy and cost.

  A method in which light is incident on an optical waveguide through an optical fiber, passive adjustment is performed while observing the end surface of the optical waveguide with a camera, and final adjustment is performed by using a power meter connected to the optical fiber array. It has been proposed (see, for example, Patent Document 1).

JP-A-8-43676

  It is an object of the present invention to provide a configuration and method capable of aligning different types of optical transmission lines at low cost and with high accuracy by passive adjustment.

In one aspect, the optical transmission line alignment method is:
By observing the junction position of the first optical transmission path and the second optical transmission path within the same field of view with a camera disposed obliquely above the junction position of the first optical transmission path and the second optical transmission path, the camera Obtaining a relative position of the second optical transmission line with respect to the first optical transmission line on coordinates;
Obtaining an end-to-end distance between the first optical transmission line and the second optical transmission line at the joining position;
Based on the distance between the end faces and the observation angle of the camera, the amount of deviation between the relative position on the camera coordinates and the actual relative position is calculated,
The actual relative position of the second optical transmission path with respect to the first optical transmission path is calculated from the relative position on the camera coordinates and the shift amount, and the first optical transmission and the second light are calculated. Determine the alignment amount of the transmission line.

  By passive adjustment, different types of optical transmission lines can be aligned with low cost and high accuracy.

It is a figure of general passive adjustment. It is a schematic block diagram of the alignment apparatus of embodiment. It is a figure of the assembly flow of the optical module containing the alignment method of embodiment. It is a figure explaining the focus adjustment (S103) of FIG. It is a figure explaining calculation (S107) of the relative position of the optical waveguide seen from the camera of Drawing 3, and an optical fiber array. It is a figure which shows an example of acquisition of the distance between end faces of FIG. 3 (S105). It is a figure explaining the principle of acquisition of the distance between end faces of FIG. It is a figure which shows another camera arrangement | positioning example in the apparatus of FIG. It is a figure explaining acquisition of the distance between end faces when the end face of an optical waveguide and an optical fiber array inclines. It is a figure explaining calculation of the distance between end faces in the case of FIG.

  A preferred embodiment will be described with reference to the drawings. FIG. 2 is a schematic configuration diagram of the alignment apparatus 1 of the embodiment. FIG. 2 shows an alignment state when the optical waveguide chip 10 and the optical fiber array 20 are joined to assemble an optical module. The optical module assembling apparatus may be configured by incorporating the adhesive filling unit 51 and the adhesive curing unit 52 indicated by broken lines in the alignment apparatus 1 of FIG. In this case, the optical module can be assembled by bonding the optical waveguide chip 10 after alignment and the optical fiber array 20 with an adhesive and curing.

  In the optical waveguide chip 10, an optical waveguide 12 is formed on a substrate 11. Although not shown, an optical element such as a laser diode, a photodiode, or a wavelength division multiplexing filter may be incorporated in the optical waveguide 12.

  In the optical fiber array, a plurality of optical fibers 22 are arranged in a groove (not shown) formed in the glass block 21, and the tip portion of the optical fiber 22 is held by the upper block 23. By accurately aligning the tip of the optical fiber 22 and the optical waveguide 12, it is possible to pass an optical signal with low loss for each channel.

  The alignment apparatus 1 includes a stage 31 on which the optical waveguide chip 10 is mounted, a stage 32 on which the optical fiber array 20 is mounted, and a camera 40 that observes the end face of the optical waveguide chip 10 and the end face of the optical fiber array 20 within the same field of view. And a control device 50.

  The stages 31 and 32 are each capable of three-axis linear movement and three-axis rotation. The three-axis linear motion can be realized by, for example, a stepping motor-driven ball screw type, and an automatic stage with repeated positioning accuracy within ± 1 μm and resolution of 0.05 μm. Three-axis rotation can be realized, for example, by driving a two-axis gonio stage and a one-axis rotation stage with a stepping motor. The rotational positioning accuracy is within ± 0.005 degrees and the resolution is 0.003 degrees.

  In FIG. 2, the arrangement direction of the optical waveguides 12 is the x-axis, the optical axis direction of the optical waveguides 12 is the y-direction, the normal direction of the surface of the optical waveguide chip 10 is the z-axis, and the rotation directions about the respective axes are Let θx, θy, and θz.

  The camera 40 is, for example, a CCD camera with 5 million pixels mounted with a 20 × magnification lens. The camera 40 is mounted on a camera stage 41 that can move in three axes. The camera stage 41 has the same performance as the linear stage automatic stages 31 and 32. The camera 40 is disposed obliquely above the optical waveguide chip 10 and the optical fiber array 20 that are close to each other, and observes the end portion of the optical waveguide 12 and the end surface of the optical fiber array 22 in the same field of view. The observation direction of the camera 40 is in the yz plane, and the angle formed by the observation direction of the camera and the optical axis of the optical waveguide 12 is φ, as will be described later. The observation angle φ may be fixed in advance, for example, 10 degrees.

  The camera 40 is connected to the image processing unit 45 of the control device 50. The camera stage 41 is connected to the camera stage controller 43 of the control device 50 and driven and controlled. The stages 31 and 32 are connected to a stage controller 33 of the control device 50 and driven and controlled.

  FIG. 3 is an assembly flow of the optical module including the alignment method of the embodiment. First, in step S101, the optical waveguide chip 10 and the optical fiber array 20 are brought close to each other, and the position is roughly adjusted. For this rough adjustment, for example, a low-resolution, low-magnification general-purpose camera capable of photographing the entire joint between the optical waveguide chip 10 and the optical fiber array 20 may be used separately from the position detection camera 40. It may be done with the naked eye. When a general-purpose camera is used, the camera is disposed immediately above the joining position, and the two are brought close to each other so that the end face of the optical waveguide chip 10 and the end face of the optical fiber array 20 face each other. In the alignment apparatus 1, when the initial positions of the optical waveguide chip 10 and the optical fiber array 20 are set in advance, coarse adjustment may be performed by driving one or both of the stages 31 and 32 by a predetermined amount. . The accuracy of the coarse adjustment may be about 100 to several hundreds of μm. Further, the angle in the θx direction of the surface of the optical waveguide chip 10 and the angle in the θx direction of the upper surface of the optical fiber array 20 are measured using an autocollimator (not shown), and are adjusted in advance by the stage controller 33 and the stages 31 and 32. It is desirable.

  Next, in step S103, at least two channels on both ends of the optical waveguide chip 10 and the optical fiber array 20 that are close to each other, and if necessary, the vicinity of the cores of all the channels are observed with the camera 40. The array is placed in the same field of view of the camera 40. For example, while the observation angle φ is fixed, the camera stage 41 and the stage 31 on which the optical waveguide chip 10 is mounted are driven so that the edges of the optical waveguide chip 10 are focused on the optical waveguides 12 of at least both ends ( Alternatively, adjustment is performed so that the optical waveguides 12 of all channels are in focus. In a state where both ends or all of the optical waveguides 12 are in focus, the stage 32 on which the optical fiber array 20 is mounted is driven, and the optical fiber array 20 is moved to a position where the end face of the optical fiber 22 array falls within the in-focus range. It is made to approach the end surface of the optical waveguide chip 10. By focusing on both end faces of the optical waveguide 12 and the optical fiber 22, the end face of the optical waveguide 12 and the end face of the optical fiber 22 can be observed within the same field of view of the camera 40.

  FIG. 4 is a diagram for explaining the focus adjustment in S102 of FIG. 4A is an image observed by the camera 40, and FIG. 4B is a schematic diagram thereof. In FIG. 4, for the sake of convenience, an image of one channel is shown. In this example, the focal position of the core 25 of the single-mode optical fiber 22 is aligned with the rib-shaped optical waveguide 12. When there is no protrusion on the chip surface, such as a channel type optical waveguide, a convex portion or a concave portion for alignment is formed in advance at the surface end near the optical waveguide 12, and an image for focus adjustment is acquired.

  In FIG. 4A, when the optical fiber array 20 is not focused, the image of the optical fiber 22 is not reflected. By driving the stage 32 and bringing the optical fiber array 20 closer to the in-focus position, the optical waveguide 12 and the optical fiber core 25 are within the same field of view of the camera 40. For example, the image processing unit 45 of the control device 50 may determine the in-focus position by acquiring a contrast level in a predetermined pixel area and determining the position where the contrast reaches a peak as the in-focus position.

Even if focusing is performed in the observation direction of the camera 40, the optical waveguide chip 10 and the optical fiber array 20 are still in a rough alignment state. Space coordinates (hereinafter referred to as “camera coordinates”), W _{0 is} in the x-axis direction (width direction), and H _{0 is} in the z-axis direction (height direction). The relative positions H ₀ and W ₀ of the optical fiber core 25 with respect to the optical waveguide 12 on the camera coordinates are acquired and stored. The relative position (H ₀ , W ₀ ) of the optical fiber core 25 with respect to the optical waveguide 12 in camera coordinates can be obtained by the image processing unit 45 of the control device 50 using pattern matching, centroid detection, or the like.

  Returning to FIG. 3, in step S105, the distance d between the end faces of the optical waveguide 12 and the optical fiber 22 is obtained in a state where the optical waveguide 12 and the optical fiber 22 are in the same field of view (both are in focus). . The distance d between the end faces is a distance between the optical waveguide 12 and the end face of the optical fiber 22 in the y-axis direction (optical axis direction). For obtaining the distance d, for example, the stage 32 is driven to move the optical fiber array 20 until it contacts the optical waveguide chip 10, and a collision position is detected using a contact sensor (not shown). The distance d between the end faces at the optical waveguide position is obtained from the driving amount of the stage 32 at this time.

  Next, in S107, the actual relative position of the optical fiber core 25 with respect to the optical waveguide 12 is calculated. The actual relative position can be obtained from the relative position (apparent relative position) on the camera coordinates, the distance d between the end faces, and the observation angle φ.

  FIG. 5 is a diagram for explaining the calculation of the actual relative position in S107. When the camera 40 observes the joint portion between the optical waveguide 12 and the optical fiber core 25 from obliquely above the optical waveguide 12, the position of the optical fiber core 25 appears above the actual position. Actually, even when the positions of the optical waveguide 12 and the optical fiber core 25 are aligned in the z-axis direction (height direction), the position of the optical fiber core 25 is ΔH higher than the optical waveguide 12 within the field of view of the camera 40. Observed on the upper side. This shift amount ΔH can be expressed as ΔH = d × sin φ using the observation angle φ of the camera 40 and the distance d between the end faces.

The (apparent) relative position (H ₀ , W ₀ ) on the camera coordinates can be converted into the actual relative position (H ₁ , W ₁ ) using ΔH according to equation (1).

(H ₁ , W ₁ ) = (H ₀ + ΔH, W ₀ ) (1)
This calculation is performed on at least the two outermost channels. Repeat for all channels if necessary.

Returning to FIG. 3, in S109, the optical waveguide 12 and the optical fiber array 25 are aligned. Assuming that the actual relative positions of the optical waveguide 12 and the optical fiber core 25 at both ends (left and right) channels are (H _1L , W _1L ) and (H _1R , W _1R ), H _1L ² + W _1L ² + H _1R ² + W _1R ² minimum, i.e. so that the total of the difference in position between the optical waveguide 12 and the optical fiber core 25 in each channel is minimized, to adjust the position of the optical fiber array 20. Specifically, based on the movement amount calculated by the image processing unit 45, the stage controller 33 controls the stage 32 to align the optical fiber array 20 in the x-axis and z-axis directions. Even when the actual relative positions (positional differences) are obtained for all channels, the movement amounts in the x-axis and z-axis directions are calculated so as to minimize the sum of squares of all components.

  At this time, alignment in the y-axis direction may be performed. When the distance d between the end faces is acquired by the contact sensor in S105, the optical waveguide chip 10 and the optical fiber array 20 are in contact with each other. However, when the multi-channel optical waveguide chip 10 and the optical fiber array 20 are actually joined, the tip position (position in the y-axis direction) of the optical fiber 22 at the end face of the optical fiber array 20 may vary. In this case, if a small gap is provided between the optical waveguide chip 10 and the optical fiber array 20 for optical coupling, the dispersion is absorbed and a low-loss connection can be achieved over the entire channel.

  In addition, when the optical waveguide chip 10 and the optical fiber array 20 are bonded with an adhesive, it is desirable that the adhesive can be filled using the capillary phenomenon between the end faces.

  For these reasons, the optimum distance in the y-axis direction between the optical waveguide chip 10 and the optical fiber array 20 is set in advance, and the stage controller 33 sets the position of the optical fiber array 20 in the x-axis and z-axis directions. The position in the y-axis direction may be controlled.

  Next, for example, an ultraviolet curable adhesive is filled between the end faces of the optical waveguide chip 10 and the optical fiber array 20 in S111. In this example, an adhesive having a viscosity of 300 cP or less and a refractive index equivalent to that of quartz is used. When the adhesive filling unit 51 is used as shown in FIG. 1, for example, the adhesive is dropped in the vicinity of the end face of the optical waveguide 12 by the tube type auto-dispenser 51, so that the optical waveguide chip 10 and the optical fiber array 20 are caused by capillary action. An adhesive can be filled between the end surfaces of the two.

  Finally, the adhesive filled in S113 is irradiated with ultraviolet rays and cured. If necessary, the cured bonded body is heat cured in a baking furnace or the like. Thereby, joining of the optical waveguide chip 10 and the optical fiber array 20 is completed.

  FIG. 6 shows another method for obtaining the distance d between the end faces in FIG. 3 (S105). In the example described above, the end-to-end distance d is acquired using the contact sensor, but in FIG. 6, the end-to-end distance d is obtained without contact.

After the observation step S103, the focus position on the real image of the optical waveguide 12 is acquired in S201. The acquisition of the focus position may be performed by storing the position of the camera 40 when the optical waveguide 12 is focused when the focus is adjusted in S103, and reading this. As shown in FIG. 7, the real image of the optical waveguide 12 is an image directly taken when the edge of the optical waveguide 12 is observed by the camera 40 at an observation angle φ. The camera position at this time is y ₁ .

Next, the focus position to the reflected image of the optical waveguide 12 is acquired by S202. Referring to FIG. 7, when the camera stage 41 is driven and the position of the camera 40 in the y-axis direction is changed while maintaining the observation angle φ, the real image of the optical waveguide 12 deviates from the field of view of the camera 40. However, when the camera 40 is moved to a certain position, the light reflected by the end face of the optical fiber 22 is focused on the edge of the optical waveguide 12, and a reflected image of the optical waveguide 12 can be obtained. The position of the y-axis direction of the camera 40 at this time is y _2.

Next, the distance d between the end faces of the optical waveguide 12 and the optical fiber array 20 is calculated using the camera positions y ₁ and y ₂ in S203. As shown in FIG. 7, the optical path length of the reflected light reflected by the end face of the optical fiber 22 to the edge of the optical waveguide 12 is L2. When it is assumed that the optical fiber array 20 does not exist, the optical path length from the end surface reflection position of the optical fiber 22 to the intersection of the straight light and the extension line of the optical waveguide 10 is L1. Since L1 = L2 and the movement amount of the camera 40 is | y ₂ −y ₁ |, the distance d between the end faces can be obtained by Expression (2).

d = | y ₂ −y ₁ | (2)
Using the distance d between the end faces calculated in this way, the relative position is calculated in step S107. Since this method does not require an additional device such as a contact sensor, the apparatus cost can be reduced. Moreover, since it is non-contact, there is little influence on the optical waveguide 12 and the optical fiber 22. Further, it is also effective when there are irregularities on the end faces of the optical waveguide chip 10 and the optical fiber array 20 and the optical waveguide 12 and the optical fiber 22 cannot be contacted.

  Even when the distance d between the end faces is calculated by the method of FIG. 7, it is desirable to adjust the position in the y-axis direction at the stage of alignment (S109 in FIG. 3). This is because the distance d (S103, S105) between the end faces determined by the focus adjustment for putting the optical waveguide 12 and the optical fiber core 25 in the same field of view is not necessarily the optimum distance for optical coupling and capillary action. From the viewpoint of multi-channel optical coupling and the capillary action of the adhesive used, it is desirable to set an optimum position interval in the y-axis direction separately.

  FIG. 8 is a diagram illustrating another arrangement example of the cameras 40. Depending on the observation angle φ and the depth of field of the camera lens, there may be a case where the focus is limited to only a small region of the end face of the optical fiber array 20. In this case, as shown in FIG. 8, a mirror 61 may be arranged in the vicinity of the lens of the camera 40 to form a folding optical system, and observation may be performed from an angle close to the horizontal. Also in this case, the actual relative position is determined from the apparent relative position in camera coordinates between the optical waveguide 12 and the optical fiber core 25 in consideration of the shift amount ΔH in the z-axis direction (height direction) due to the observation angle φ. The position can be calculated and aligned.

  FIG. 9 shows the calculation of the distance between the end faces when the end faces of the optical waveguide chip 10 and the optical fiber array 20 are inclined at an angle α (for example, 8 degrees) with respect to the plane perpendicular to the optical axis. In this case, the observation angle φ of the camera 40 is set larger than the inclination angle α. Since the end face of the optical fiber array 20 is inclined, the camera 40 is moved in the y-axis direction and the z-axis direction in order to obtain a reflection image of the edge of the optical waveguide 12.

The distance d between end faces is calculated from the moving distance | y ₂ −y ₁ | of the camera 40 in the y-axis direction, the moving distance | z ₁ −z ₂ | in the z-axis direction, the observation angle φ, and the tilt angle α. be able to. With reference to FIG. 10, calculation of the distance d between end faces will be described.

The optical path length of the reflected light reflected by the end face of the optical fiber 22 to the edge of the optical waveguide 12 is L2. When it is assumed that the optical fiber array 20 does not exist, an optical path of straight light that travels straight from the end surface reflection position of the optical fiber 22 with the same optical path length as L2 is defined as L1. Even if the camera 40 moves, the observation angle φ is the same.
cosφ = (| y ₂ −y ₁ | −d) / L 1 (3)
It is.

The angle formed by the reflected light L2 and the extension line (optical axis) of the optical waveguide 12 is
π / 2-α- [π / 2- (φ-α)] = φ-2α (4)
Because
sin (φ-2α) = [(| y ₂ −y ₁ | −d) tan φ− | z ₁ −z ₂ |] / L ₂ (5)
It is.

  From Expressions (3) and (5), L1 and L2 are represented by Expression (6) and Expression (7), respectively.

Here, since L1 = L2, the distance d between the end faces is expressed by Expression (8).

d = | y ₂ −y ₁ | + [cosφ / {sin (φ−2α) −sinφ}] | z ₁ −z ₂ | (8)
According to this method, even when the joining end face of the optical waveguide chip 10 and the optical fiber array 20 is inclined, the distance d between the end faces is obtained without contact, and the relative position between the optical waveguide 12 and the optical fiber 22 is calculated. Can do.

The control device 50 of the alignment apparatus 1 may perform alignment control by an alignment program. In this case, the alignment program is sent to the control device 50.
(a) A procedure for obtaining the relative position of the optical fiber with respect to the optical waveguide on the camera coordinates of the camera for observing the joining position of the optical waveguide and the optical fiber obliquely from above in the same field of view,
(b) From the observation angle of the camera and the distance between the end faces between the optical waveguide and the optical fiber at the joining position, between the relative position on the camera coordinates and the actual relative position. A procedure for calculating the amount of deviation, and
(c) calculating the actual relative position based on the shift amount, and calculating a movement amount for aligning the optical waveguide and the optical fiber;
Is executed.

  Thus, according to the configuration and method of the embodiment, the optical transmission lines can be aligned with high accuracy by passive adjustment without using expensive equipment. Further, the optical module can be assembled with high accuracy.

The following notes are presented for the following explanation.
(Appendix 1)
By observing the junction position of the first optical transmission path and the second optical transmission path within the same field of view with a camera disposed obliquely above the junction position of the first optical transmission path and the second optical transmission path, the camera Obtaining a relative position of the second optical transmission line with respect to the first optical transmission line on coordinates;
Obtaining an end-to-end distance between the first optical transmission line and the second optical transmission line at the joining position;
Based on the distance between the end faces and the observation angle of the camera, the amount of deviation between the relative position on the camera coordinates and the actual relative position is calculated,
The actual relative position of the second optical transmission path with respect to the first optical transmission path is calculated from the relative position on the camera coordinates and the shift amount, and the first optical transmission and the second light are calculated. An optical transmission line alignment method, comprising: determining an alignment amount of a transmission line.
(Appendix 2)
The distance between the end faces is obtained by reflecting the reflected image of the first optical transmission path by the first focusing position of the camera when the real image of the first optical transmission path is acquired and the reflected light from the second optical transmission path. The alignment method according to appendix 1, wherein the alignment method is calculated based on a second in-focus position of the camera at the time of acquisition. (Claim 2)
(Appendix 3)
The observation within the same visual field is focused on the first optical transmission line by the camera, and while the focused state of the first optical transmission line is maintained, the second optical transmission line is focused. The alignment method according to appendix 1 or 2, wherein a second optical transmission line is brought close to the first optical transmission line.
(Appendix 4)
Any one of appendices 1 to 3, wherein the first optical transmission path and the second optical transmission path each have a plurality of channels, and the shift amount is calculated for at least both ends of the plurality of channels. The alignment method according to Crab.
(Appendix 5)
The actual relative position is calculated from the deviation amount for at least the channels at both ends, and the total difference between the positions of the first optical transmission path and the second optical transmission path expressed by the actual relative position is minimized. The alignment method according to appendix 4, wherein the alignment amount is calculated.
(Appendix 6)
6. The alignment direction according to any one of appendices 1 to 5, wherein the coarse adjustment of the positions of the first optical transmission line and the second optical transmission line is performed prior to observation in the same visual field.
(Appendix 7)
Based on the alignment amount, align the first optical transmission line and the second optical transmission line,
Joining the aligned first optical transmission line and the second optical transmission line;
The alignment method according to any one of supplementary notes 1 to 6, wherein:
(Appendix 8)
A movable mechanism for relatively moving the second member formed with the second optical transmission path with respect to the first member formed with the first optical transmission path;
A camera that is disposed obliquely above the junction position of the first optical transmission path and the second optical transmission path, and that observes the junction position of the first optical transmission path and the second optical transmission path within the same field of view;
The relative position of the second optical transmission path with respect to the first optical transmission path is obtained on the camera coordinates of the camera, the observation angle of the camera, the first optical transmission path and the second light at the joint position. Based on the distance between the end faces between the transmission paths, a deviation amount between the relative position on the camera coordinates and the actual relative position is calculated, and the relative position on the camera coordinates and the deviation amount are calculated. A control unit for determining a movement amount for aligning the first optical transmission and the second optical transmission line based on;
An alignment apparatus comprising:
(Appendix 9)
The control unit acquires a reflected image of the first optical transmission line from a first focus position when the camera acquires a real image of the first optical transmission line and reflected light from the second optical transmission line. The alignment apparatus according to appendix 8, wherein the distance between the end faces is calculated based on the second in-focus position.
(Appendix 10)
The relative position of the second optical transmission line with respect to the first optical transmission line is acquired on the camera coordinates of a camera that observes the joining position of the first optical transmission line and the second optical transmission line from obliquely above within the same field of view. Procedure and
From the observation angle of the camera and the distance between the end faces between the first optical transmission path and the second optical transmission path at the joining position, the relative position on the camera coordinates and the actual relative position A procedure for calculating the amount of deviation between
Calculating the actual relative position based on the shift amount and calculating a movement amount for aligning the first optical transmission path and the second optical transmission path;
Alignment program that causes the control device to execute.
(Appendix 11)
A first in-focus position when the camera acquires a real image of the first optical transmission path, and a second position when a reflected image of the first optical transmission path is acquired by reflected light from the second optical transmission path. A procedure for calculating the distance between the end faces based on the in-focus position;
The alignment program according to appendix 10, wherein the alignment program is further executed.

DESCRIPTION OF SYMBOLS 1 Position alignment apparatus 10 Optical waveguide chip 12 Optical waveguide 20 Optical fiber array 22 Optical fiber 25 Optical fiber cores 31 and 32 Stage 33 Stage controller 40 Camera 41 Camera stage 43 Camera stage controller 45 Image processing unit 50 Control apparatus

Claims (7)

By observing the junction position of the first optical transmission path and the second optical transmission path within the same field of view with a camera disposed obliquely above the junction position of the first optical transmission path and the second optical transmission path, the camera Obtaining a relative position of the second optical transmission line with respect to the first optical transmission line on coordinates;
Obtaining an end-to-end distance between the first optical transmission line and the second optical transmission line at the joining position;
Based on the distance between the end faces and the observation angle of the camera, the amount of deviation between the relative position on the camera coordinates and the actual relative position is calculated,
The actual relative position of the second optical transmission path with respect to the first optical transmission path is calculated from the relative position on the camera coordinates and the shift amount, and the first optical transmission and the second light are calculated. An optical transmission line alignment method, comprising: determining an alignment amount of a transmission line.   The distance between the end faces is obtained by reflecting the reflected image of the first optical transmission path by the first focusing position of the camera when the real image of the first optical transmission path is acquired and the reflected light from the second optical transmission path. The alignment method according to claim 1, wherein the alignment method is calculated based on a second in-focus position of the camera at the time of acquisition.   The first optical transmission path and the second optical transmission path each have a plurality of channels, and the shift amount is calculated for at least both ends of the plurality of channels. The alignment method described.   The actual relative position is calculated from the deviation amount for at least the channels at both ends, and the total difference between the positions of the first optical transmission path and the second optical transmission path expressed by the actual relative position is minimized. The alignment method according to claim 3, wherein the alignment amount is calculated. A movable mechanism for relatively moving the second member formed with the second optical transmission path with respect to the first member formed with the first optical transmission path;
A camera that is disposed obliquely above the junction position of the first optical transmission path and the second optical transmission path, and that observes the junction position of the first optical transmission path and the second optical transmission path within the same field of view;
The relative position of the second optical transmission path with respect to the first optical transmission path is obtained on the camera coordinates of the camera, the observation angle of the camera, the first optical transmission path and the second light at the joint position. Based on the distance between the end faces between the transmission paths, a deviation amount between the relative position on the camera coordinates and the actual relative position is calculated, and the relative position on the camera coordinates and the deviation amount are calculated. A control unit for determining a movement amount for aligning the first optical transmission and the second optical transmission line based on;
An alignment apparatus comprising:   The control unit acquires a reflected image of the first optical transmission line from a first focus position when the camera acquires a real image of the first optical transmission line and reflected light from the second optical transmission line. The alignment apparatus according to claim 5, wherein the distance between the end faces is calculated based on a second in-focus position. The relative position of the second optical transmission line with respect to the first optical transmission line is acquired on the camera coordinates of a camera that observes the joining position of the first optical transmission line and the second optical transmission line from obliquely above within the same field of view. Procedure and
From the observation angle of the camera and the distance between the end faces between the first optical transmission path and the second optical transmission path at the joining position, the relative position on the camera coordinates and the actual relative position A procedure for calculating the amount of deviation between
Calculating the actual relative position based on the shift amount and calculating a movement amount for aligning the first optical transmission path and the second optical transmission path;
Alignment program that causes the control device to execute.