JPH0459616B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for aligning an optical fiber. More specifically, the present invention is applicable to optical fiber fusion splicing devices, characteristic measuring devices, etc.
The present invention relates to a method for aligning the axis of an optical fiber with high accuracy in a simple, reliable, and high-speed manner.

BACKGROUND ART Conventionally, various methods have been devised for optical fiber connections such as fusion splicing and optical coupling. Among these, the V-groove connection method, in which the optical fiber is placed on the bottom of a precisely machined V-shaped groove for positioning, is widely used. In particular, when fusion splicing optical fibers, the optical fiber connection parts are placed on a pair of V-grooves and positioned, and then one V-groove is slightly moved relative to the other V-groove to precisely connect the optical fibers. Methods of aligning the fiber positions are known.

The reason why such a slight movement of the V-groove is performed is that the positioning accuracy of the optical fiber is insufficient just by placing it on the V-groove. Therefore, for simple measurements,
Connection is made by simply placing the optical fiber in the V-groove. On the other hand, in order to perform fusion splicing with low loss and excellent characteristics and to measure characteristics with high precision, it is essential to connect optical fibers by moving the V-groove and adjusting the position of the optical fibers as described above. be.

FIG. 7 is a schematic diagram showing an example of an optical fiber alignment device including such a fine movement device.

In FIG. 7, reference numbers 1 and 2 indicate optical fibers that are fusion spliced or optically coupled. The connecting end portions of the optical fibers 1 and 2 are stripped of the coating of the optical fiber core wire, forming bare optical fiber portions 1A and 2A, respectively. Groove 3
It is placed on the bottom of A and 4A. A presser 3 is placed on the bare optical fiber parts 1A and 2A.
A and 4B are listed.

A light source 5 is connected to the other end of one optical fiber 1, and a photodetector 6 is connected to the other end of the other optical fiber 2. It is connected to a power meter 8 installed nearby, and the amount of light received is displayed on the power meter 8. Thus, power meter 8
By slightly moving one or both of the V-groove blocks 3 and 4 in two different directions perpendicular to the optical axes of the optical fibers 1 and 2, for example, horizontal and vertical directions orthogonal to each other, while looking at the ,
One or both of the bare optical fiber parts 1A and 2A is slightly moved to determine the relative position with respect to the bare optical fiber parts 1A and 2A where the amount of light received is maximum. When the amount of light received reaches the maximum, if fusion splicing is to be performed, fusion splice the ends of the bare optical fibers 1A and 2A,
In the case of characteristic measurement, measurement processing such as coupling light of a specific wavelength or output from the light source 5 to the optical fiber 2 via the optical fiber 1 is performed.

Problems to be Solved by the Invention However, the above alignment method has the following problems. One problem is that alignment relies on the light passing through the optical fiber to be connected, so if the initial position of the optical fiber on the V-groove is not appropriate, the light from optical fiber 1 to optical fiber 2 is If they are not combined, alignment will not be possible at all.

Another problem is that the light passing through the connected optical fiber is very weak, so high performance is required of the photodetector, power meter, and light source.

Another problem is that even if high-performance parts are used, the amount of light received by the photodetector is often very small in this method, especially in the early stages of alignment. This results in instability, and as a result, it takes a considerable amount of time for alignment (for example, see Yasuyuki Kato et al., "Connecting Single Mode Optical Cables", 1983, Research and Practical Application Report No.
There is a report in Vol. 32, No. 3, P80-P81 that the average time per end is 1 minute).

In particular, when considering connections between single mode optical fibers, most single mode optical fibers have a small core diameter of 10 μm or less. Therefore, during alignment, the light beam emitted from the optical fiber connected to the light source is narrow, and the portion that can receive the narrow light beam, that is, the core, is also very small. Moreover, when the above-mentioned alignment method was controlled and automated by a computer and furthermore, automatic fusing was performed, there were many failures. Therefore, in order to prevent this failure, it was necessary to monitor the connection part with a high-magnification microscope when setting it on the V-groove (Mitsuru Miyauchi et al., "Core connection of optical cables", 1981, Research and Practical Application Report, Vol. 30, No. 9, 88). Pages indicate the need for monitoring mechanisms to reduce operational difficulties and failures).

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, the present invention aims to provide an optical fiber alignment method that can reliably, easily, and quickly align the optical fibers to be connected.

Means for Solving the Problems The method of aligning the mutually opposing end surfaces of two optical fibers provided by the present invention is based on a V-groove formed near the end of the first optical fiber in the first support block. The first optical fiber is supported horizontally and fixed so as not to move by placing it on the bottom of the support block, while the vicinity of the end of the second optical fiber is moved relative to the first support block. The second supporting block is placed on the bottom of a V-groove formed in a possible second support block and having approximately the same height as the above-mentioned V-groove.
horizontally supporting the optical fiber and fixing it so that it does not move, and at this time, the tip of the second optical fiber protrudes from the first support block and is perpendicular to the extension of the axis of the first optical fiber. 2 arranged opposite to each other across the extension line in a plane
A line that connects the light output end and the light input end of at least one pair of photosensors fixed to the arm of the book.
the first support block or the second support block in a first direction perpendicular to the axial direction of the two optical fibers. By moving the blocks relative to each other and blocking the light directed from the light output ends of the pair of optical sensors to the light input ends by the tips of the second optical fibers, the amount of light received at the light input ends of the optical sensors is set to a predetermined value. The relative movement between the first support block and the second support block is stopped when the attenuation is below, and the two optical fibers are then moved until the amount of light sent from one of the two optical fibers to the other reaches its maximum. The positions of the two optical fibers are adjusted by moving the first support block or the second support block relative to each other in a second direction perpendicular to the axial direction of the optical fiber and perpendicular to the first direction. It is characterized by fine adjustment.

The above-mentioned "first direction perpendicular to the axial direction of the two optical fibers" may be a horizontal direction, a vertical direction, or an oblique direction. In a particular embodiment of the invention, it is horizontal.

Function In the optical fiber alignment method according to the present invention as described above, the light flux from the light emitting optical fiber of the optical sensor to the light receiving optical fiber is directed to the first optical fiber supported by the first supporting part. Since the relationship is perpendicular to the extension line of the optical axis of the incident or output port of the connected light, when the first support part is moved in the movable direction and the light flux is blocked, the first support part is By stopping the support part, the input or output port of the first connected light can be aligned with the second connected optical fiber in the moving direction of the first support part.

Since the alignment of the optical fibers is performed in a non-contact manner, the optical fibers can be accurately positioned without disturbing or destroying the optical fibers to be connected.

Embodiments Hereinafter, embodiments of the optical fiber alignment method according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a conceptual perspective view of an optical fiber alignment device for carrying out the optical fiber alignment method of the present invention, FIG. 2 is a partial side view thereof, and FIG. 3 is a partial plan view thereof. It is a diagram.

The illustrated fiber optic alignment apparatus includes a carriage 12 mounted on a base 10, such as the head of a fiber optic fusion splicer.
It is capable of reciprocating movement in the direction of arrow A. A support block 14 is mounted on the movable table 12. The support block 14 is formed with a V-groove 18 on the bottom of which one optical fiber 16 to be connected is placed, and a holding block 20 is placed on the optical fiber 16 to be connected placed on the bottom of the V-groove 18. and holds the optical fiber 16 to be connected.

On the front surface of the support block 14, arms 22 and 24 protrude forward from the upper and lower parts sandwiching the bottom of the V-groove 18. The arms 22 and 24 include
Optical fibers 26 and 28 constituting the optical sensor are each fixed. Optical fibers 26 and 28
are located perpendicularly opposite to each other in a plane perpendicular to the extension line of the axis of the optical fiber 16 to be connected held in the V-groove 18 of the support block 14 so as to sandwich the extension line.

Another support block 30 is attached to the base 10 so as to face the support block 14. A V-groove 32 is formed in the support block 30 at the same height as the V-groove 18 of the support block 14. At the bottom is another connected optical fiber 3.
4 is placed thereon and is held down from above by a holding block 36 so as to be movable in the axial direction.

The movable platform 12 under the support block 14 includes, for example, as shown in FIG. It is configured. The base 42 is moved so that the moving direction of the carrier 44 is in the direction of arrow A in FIG.
is fixed, for example, to a base 10, and a support block 14 is attached to a carrier 44. carrier 44
has an arm 46 extending in a direction perpendicular to the sliding direction thereof. The arm 46 rotatably holds the tip of a feed screw 48, and the center portion of the feed screw 48 is threaded and supported by a female screw 50 fixed to the base 42. The other end of the feed screw 48 is coupled to the output shaft of a motor 52 whose case is attached to the base 42 so as to be slidable in the axial direction but not rotatable. Therefore, by driving the motor 52, the feed screw 48 is rotated, and depending on the direction of rotation, the arm 46 or the carrier 44 is advanced or retracted. In that way, the moving platform 12 is moved by the arrow A in FIG.
The support block 14 supported thereon can be reciprocated in the direction of arrow A.

FIG. 5 is a circuit diagram showing an example of the detection circuit of the optical sensor and the drive control circuit of the motor 52. A light source such as a light emitting diode 54 or a semiconductor laser,
The other end of the optical fiber 26 is coupled, and the light emitted from the optical fiber 26 is connected to the optical fiber 26 and 2.
enters the optical fiber 28 through a gap between 8 and 8;
It is coupled to a photodetector, such as a phototransistor 56, coupled to the other end of optical fiber 28. The collector voltage of the phototransistor 56 is
The output of the threshold circuit 60 is connected to the base of an output transistor 62, and a relay R is connected between the collector of the output transistor 62 and the power supply. Normally open contact R _a1 of that relay R, normally open contact X _a1 of another relay X, and motor 5
2 are connected in series to the power supply. The other relay X is a push button switch PB and a relay R.
is connected to the power supply in series with another normally open contact R _a2 . Furthermore, another normally open contact X _a2 of relay X is connected in parallel to pushbutton switch PB to form a self-holding circuit.

Now, when the light from the light emitting diode 54 is incident on the phototransistor 56, the phototransistor 56 becomes conductive, its collector becomes a low voltage, and the low voltage signal is sent to the threshold circuit 60 via the amplifier 58. is input. The threshold circuit 60 outputs a high level voltage signal to the base of the transistor 62 to place the transistor 62 in a conductive state when the input voltage is lower than a predetermined threshold voltage. As a result, current flows through relay R, and its normally open contacts R _a1 and R _a2 become
It is in a closed state. In this state, when pushbutton switch PB is pressed, current flows through relay X, its normally open contacts X _a1 and X _a2 become closed, and motor 5
2 operates, the support block 14 is displaced in one predetermined direction of the arrow A, and the relay
becomes a self-holding state.

By moving the support block 14, the optical fiber 2
When the optical fiber 34 to be connected enters between the phototransistor 6 and 28 and the light beam therebetween is gradually blocked, the amount of light incident on the phototransistor 56 decreases, its conduction resistance increases, and its collector voltage increases. rises. However, while the input voltage is lower than the above-mentioned predetermined threshold voltage, the threshold circuit 60 outputs a high-level voltage signal to the base of the transistor 62 to maintain the conduction state of the transistor 62, thereby controlling the displacement of the support block 14. sustain.

However, when the light beam between the optical fibers 26 and 28 is completely blocked by the connected optical fiber 34, the amount of light incident on the phototransistor 56 becomes zero, and the phototransistor 56 becomes non-conductive. Thus, the collector voltage becomes the power supply voltage, and the input voltage of the threshold circuit 60 becomes higher than the above-mentioned predetermined threshold voltage. As a result, the threshold circuit 60 outputs a low level voltage signal to the base of the transistor 62, rendering the transistor 62 non-conductive and cutting off the current flowing through the relay R. Therefore, its normally open contact R _a1 is opened, the motor 52 is stopped, and the displacement of the support block 14 is stopped. At the same time, the normally open contact R _a2 also opens, cutting off the current in relay X and releasing the self-holding state.

Therefore, the parts up to the threshold circuit 60 in FIG. 5 constitute the detection circuit of the optical sensor, and the part to the right of the output transistor constitutes the drive control circuit for the motor 52.

Next, the operation of the optical fiber alignment device whose configuration has been explained above will be explained.

First, one optical fiber 16 of a pair of optical fibers to be connected is connected to the support block 14.
Place it on the bottom of the V-groove 18 and press it with the press block 20 from above. At this time, the tip of the optical fiber 16 to be connected is adjusted so that it is located closer to the support block 14 than the straight line connecting the optical fibers 26 and 28. As a result, the extension line of the optical fiber 16 to be connected intersects the straight line connecting the optical fibers 26 and 28. Then, the other optical fiber 34 to be connected is placed on the bottom of the V-groove 32 of the support block 30, and is pressed from above with a presser block 36. Then, the tip of the optical fiber 34 to be connected is connected to the optical fiber 26.
and 28 so that it is located on the support block 14 side.

At this time, as shown in FIG. 3, the optical fiber 34 to be connected is positioned ahead of the optical fibers 26 and 28 in the direction of arrow B, and the initial moving direction of the support block 30 is in the direction of arrow B. Suppose it is in the direction of . At this time, when the push button switch PB is pressed, the motor 52 operates to move the support block 14, that is, the connected optical fiber 16 in the direction of arrow B while the light beam is incident on the optical fibers 26 to 28. . Eventually, when the connected optical fiber 34 reaches between the optical fibers 26 and 28,
The connected optical fiber 34 gradually blocks the light entering the optical fiber 28, and finally completely blocks the light from entering the optical fiber 28. This is sensed by the detection circuit shown in FIG. 5, and the motor drive control circuit shown in FIG. 5 is activated to stop the motor 52. As a result, the connected optical fiber 16 is connected to the connected optical fiber 34.
can be positioned at a fixed position suitable for connection.

In this way, the pair of optical fibers 26 and 28 constituting the optical sensor are placed on the extension axis of the optical fiber 16 to be connected held by the support block 14 that supports the optical fibers 26 and 28. If installed so as to sandwich the optical fiber 34
Even if the position of the optical fiber 16 to be connected is greatly deviated from the position of the optical fiber 34, the entire support block 14 is moved in the direction of the arrow B and the movement is stopped when the optical fiber 34 is detected. 16 can be aligned in one direction perpendicular to their axes, in the example shown horizontally.

Once the horizontal position is determined, vertical alignment may be performed in the same manner as in the prior art so that the light coupled from one of the connected optical fibers 16 and 34 to the other is maximized. In addition, if more precise alignment is required, the optical fiber 16 to be connected can be
Centering may also be performed in the horizontal direction so that the light coupled from one side of 34 to the other side is maximized.
After that, although not shown, for example, the connected optical fiber 16 is also connected to the optical fibers 26 and 28.
A current is applied between the arc electrodes disposed substantially orthogonally to the optical fibers 16 and 34, and the optical fibers 16 and 34 to be connected are brought into contact with each other to perform fusion splicing.

In order to reciprocate the support block 14 in the direction of the arrow A, for example, the range of movement of the support block is limited, a limit switch is provided at the limit of the range of movement, and when the limit switch detects the support block, the motor 52 is moved. It may be configured to reverse the rotation of.

Further, in the above embodiment, the optical fiber 2
The optical sensors 6 and 28 are capable of highly accurate position detection. For example, optical fibers 26, 28
As a result of prototyping an optical fiber alignment device, we used a step-type optical fiber with an outer diameter of 125 μm and a core diameter of 80 μm, the distance between the end faces was 4 mm, and an LED with an output wavelength of 0.90 μm as a light source. The detection accuracy is
When the outer diameter of the optical fiber to be connected was 125 μm, the difference was ±1 μm. This accuracy was high enough to be applied to optical fiber connections.

Such position detection accuracy can be achieved for the following reasons. Even if the core diameter is 80μm
Even if you use the optical fiber, the light emitted from the optical fiber on the light output side is diffused and only the light in the center enters the optical fiber on the reception side, so the diameter of the luminous flux used for photodetection is substantially small. can do. Also,
By increasing the accuracy of the threshold circuit that receives the output of the photodetector connected to the light-receiving optical fiber, even slight differences in the amount of received light can be detected. In this way, we were able to achieve an accuracy of ±1 μm. Therefore, by using an optical fiber with a core diameter of 80 μm or less and using a sufficiently accurate threshold circuit, an accuracy of ±1 μm or less can be achieved. Here, a method of detecting reflected light can be considered for such a sensor, but for a small and non-planar object such as an optical fiber, it is possible to detect the light that has passed through the space as in the present invention. The detection accuracy is also higher, the distance between the sensors can be longer, and the tolerance range for the initial positioning accuracy of the detected object can be wider.

In the above embodiment, one optical sensor using a pair of optical fibers is used for alignment in the horizontal direction, but two optical sensors may be used. Alignment may be further facilitated by using two optical sensors, for example by using a pair of optical fibers in directions perpendicular to each other, such as horizontal and vertical directions.

That is, the optical fibers 26A and 28A are mounted on the support block 14 so as to be perpendicular to and coplanar with the optical fibers 26 and 28, as depicted in dotted lines in FIG. , the support block 14 is also movable in the vertical direction. Alternatively, as similarly drawn with dotted lines in FIG.
The optical fiber 16 to be connected held by the support block 14 is held in the support block 14 horizontally so as to sandwich the extended axis from the horizontal direction on the extension of the axis of the optical fiber 34 to be connected held by the support block 32. It is attached to a support block 32 in a sandwiching manner so that the support block 32 can be displaced in the vertical direction.

Furthermore, in the above embodiment, a system was adopted in which a motor rotates a screw and the support block is moved by the feed of the screw. However, a method in which the support block is elastically supported, a spring is attached to the support block, the spring is fed, and the spring pressure deforms the elastic support of the support block to displace the support block and perform fine adjustment (so-called stress If the method allows fine adjustment, such as the strain method,
Any support block adjustment method may be used.

Further, in the above embodiments, an example was shown in which an optical fiber was used as an input or output port for the first connected light, but an optical system using a lens, an aperture, or the like may be used. It should be added here that the effectiveness of the present invention is greatly demonstrated when the input and output apertures are both very small, such as between single mode fibers.

FIG. 6 is a schematic configuration diagram showing an example of an optical fiber characteristic measuring device that can incorporate the optical fiber alignment method according to the present invention.

In FIG. 6, reference numeral A indicates a set stage, and reference numerals B and C indicate measurement stages. At the set stage A, both ends of the optical fiber to be measured 72A are set on the moving table 70A. Next, the moving table 70A
At the same time, the optical fiber 72A to be measured is moved in the direction of arrow A and positioned on the measurement stage B, where necessary characteristic measurements are performed. On the other hand, the next moving table 70B is placed on the setting stage A, and both ends of the next optical fiber to be measured 72B are set. Then, the optical fibers to be measured 72A and 72B are moved in the direction of arrow A together with the moving tables 70A and 72A, and the optical fibers to be measured 72A and 72B are moved in the direction of arrow A.
is positioned on the measurement stage C, and the optical fiber to be measured 72B is positioned on the measurement stage B.
In this state, the next moving table 70C is placed on the set stage A, and the next optical fiber to be measured 72C is placed on the set stage A.
Both ends of are set. FIG. 6 shows the state at this time.

In this way, by setting the optical fiber to be measured on set stage A and performing measurements on measurement stages B and C, characteristics can be measured simultaneously over many items.

The measurement stage B includes a light source 74B and a photodetector 7.
6B, one end of which is connected to the light source 74B and the photodetector 76B, respectively, and the other ends of the measuring instrument side optical fibers 78B and 80B are held in the measuring instrument side holders 82B and 84B. The distance between the measuring device side optical fibers 78B and 80B held by the measuring device side holders 82B and 84B is the same as the distance between both ends of the optical fibers to be measured set on the moving tables 70A to 70C, respectively.

Similarly, the measurement stage C is provided with a light source 74C and a photodetector 76C.
The other ends of measuring instrument side optical fibers 78C and 80C, one end of which is connected to optical fiber 4C and photodetector 76C, respectively, are held by measuring instrument side holders 82C and 84C.

In the optical fiber characteristic measuring apparatus as described above, it is important that both ends of the optical fiber to be measured and the optical fiber on the measuring instrument side are connected with low loss in each measurement stage. For example, when measuring the transmission loss of a graded index optical fiber, it is desirable to suppress the axis misalignment between the measuring instrument side optical fiber and the optical fiber to be measured to 1 μm or less.

However, the movement of the moving table and the positional accuracy of the optical fiber under test on the moving table are difficult.
It is extremely difficult to keep the thickness below 1 μm.
In particular, in the above-mentioned type of optical fiber characteristic measuring device, not only the positional accuracy of the optical fiber to be measured on the moving table but also the positional accuracy of the moving table after positioning the moving table on the measuring stage is important. It is added as a factor of variation in the position of the optical fiber end. For this reason, it is necessary to perform alignment for axis alignment after moving and positioning the moving table.

However, as in the conventional technology, the amount of light that passes from the light source through an optical fiber on the measuring instrument side and enters one end of the optical fiber to be measured, and from the other end passes through another optical fiber on the measuring instrument side and enters the photodetector. If the method of measuring and aligning to maximize the value is used for alignment, the photodetector may not be able to detect light due to positional deviation at the end of the optical fiber to be measured. In some cases, the light is too weak, the alignment is unstable, and the alignment fails, or the alignment takes a long time.

If the optical fiber alignment device according to the present invention is applied to such an optical fiber characteristic measuring device, even when both ends of the optical fiber to be measured are connected to the optical fiber on the measuring instrument side at the same time, the connection can be made automatically and reliably. can be done.

That is, the moving tables 70A, 70B, 70
Each of C is provided with a support block 1 as shown in FIG.
4 together with the moving platform 12, or
Measuring instrument side holder 82B, 84B, 82C, 84C
is constituted by a support block 14 as shown in FIG. The measuring instrument side holder is generally configured to be movable in the horizontal and vertical directions perpendicular to the axis of the measuring instrument side optical fiber, so when the measuring instrument side holder is configured with the support block 14, special ,
There is no need to provide the moving table 12. Furthermore, when a V-groove block is used to hold the optical fiber to be measured and the optical fiber on the measuring instrument side, the vertical deviation between the optical fiber to be measured and the optical fiber on the measuring instrument side is not so large. Therefore, horizontal alignment is generally sufficient.

Next, the operation in the latter case will be explained. At set stage A, both ends of the optical fiber to be measured are set on a moving table, and then the moving table is moved and positioned on measurement stage B. At that point, the centering device according to the invention is activated. That is, on the measurement stage B, the pair of support blocks 14 holding the measuring instrument side optical fibers 78B and 80B respectively move in the horizontal direction, and the optical fibers 26 and 28 of the optical sensor provided on each support block 14 are moved. When the beam of light is interrupted by the optical fiber to be measured, the horizontal movement of each support block is stopped. Thereafter, the amount of light detected by the photodetector 76B is monitored, and the support block holding the measuring instrument side optical fibers 78B and 80B is slightly displaced in the vertical and horizontal directions so that the amount of detected light is maximized. and,
Displacement is stopped until the detection light power reaches its maximum, thus completing precise alignment. A similar operation is performed on measurement stage C as well.

As described above, if the optical fiber alignment method according to the present invention is applied to an optical fiber characteristic measuring device, the position of the optical fiber can be reliably detected, and at that position, the optical fibers can be aligned in one direction perpendicular to the axes of the optical fibers. Since the positions are aligned, the amount of deviation to be subsequently aligned is small and the direction of deviation is known, improving the certainty of alignment and shortening the alignment time. Therefore,
By applying the optical fiber alignment method according to the present invention, multiple characteristics can be efficiently measured simultaneously.

In the above example, there are two measurement stages B and C, but the optical fiber alignment method according to the present invention can be applied even if three or more measurement stages are provided. In addition to the number of measurement stages, it can also be applied to optical fiber characteristic measurement equipment that measures different measurement items by measuring the light passing through the optical fiber such as transmission loss, frequency characteristics, and backscattering for each measurement stage. .

In addition, in the above optical fiber characteristic measuring device, the optical fiber to be measured and the optical fiber on the measuring device side are connected, but in the case of measurement, unlike fusion splicing, the connection is made directly to the light source, or the optical fiber is connected directly to the light source. In some cases, it may be used directly with a photodetector with a large area. In such a case, the paired optical fibers 26
and 28, and it is often sufficient to perform positioning only with the optical sensor.

In addition, in the above example, the axis was aligned by alignment, but by changing the installation position of the optical fibers that form the pair of optical sensors, it is also possible to intentionally position the optical sensor at a position offset from the axis. .

Effects of the Invention As is clear from the above, the optical fiber alignment device according to the present invention can align the optical fibers to be connected with high precision, reliably, and at high speed.

[Brief explanation of the drawing]

FIG. 1 is a conceptual perspective view of an optical fiber alignment device for implementing the optical fiber alignment method of the present invention, and FIG. 2 is a partial side view of the optical fiber alignment device of FIG. 1. 3 is a partial plan view of the optical fiber alignment device shown in FIG. 1, and FIG. 4 is a schematic perspective view of a moving stage used in the optical fiber alignment device shown in FIG. 1. 5 is a circuit diagram of a detection circuit of an optical sensor and a drive control circuit of a motor of a moving table, and FIG. 6 is a circuit diagram of an optical fiber characteristic measuring device to which the optical fiber alignment method according to the present invention can be applied. FIG. 7 is a schematic diagram showing an example of a conventional optical fiber alignment device, and FIG. 8 is a perspective view showing an example of a V-groove block. . [Main reference numbers], 1, 2... Optical fiber to be connected, 3, 4... V-groove block, 5... Light source, 6...
...Photodetector, 8...Power meter, 10...Base, 12...Moving table, 14...Support block, 1
6... Optical fiber to be connected, 18... V groove, 20...
...Press block, 22, 24...Arm, 2
6, 28... Optical fiber, 30... Support block, 32... V groove, 34... Connected optical fiber,
42... Base, 44... Moving table, 48...
...Feed screw, 50...Female screw, 52...Motor,
54... Light emitting diode, 56... Phototransistor, 60... Threshold circuit, 62... Output transistor, R, X... Relay, 70A, 7
0B, 70C...Moving table, 72A, 72
B, 72C...Optical fiber to be measured, 74A, 74
B, 74C...Light source, 76A, 76B, 76C...
...Photodetector, 78B, 78C, 80B, 80C...
...Measuring instrument side optical fiber, 82B, 82C, 84
B, 84C... Measuring instrument side holder.

Claims (1)

[Claims] 1. The first optical fiber 16 is horizontally placed by placing the vicinity of the end of the first optical fiber 16 on the bottom of the V-groove 18 formed in the first support block 14. The second optical fiber 34 is supported and fixed so that it does not move, while the second optical fiber 34 is held near its end by the first
A second support block 14 movable relative to the support block 14 of
is formed in the support block 30 of the V-groove 18.
The second optical fiber 34 is supported horizontally and fixed so as not to move by placing it on the bottom of the V-groove 32 having approximately the same height as the
The tip portions of the optical fibers 34 protrude from the first support block 14 and are arranged opposite to each other across the extension line in a plane perpendicular to the extension line of the axis of the first optical fiber 16. arm 2
The second optical fiber 34 is connected to the first support block 14 in a state closer to the first support block 14 than a straight line connecting the light output ends and the light input ends of at least one pair of optical sensors 26 and 28 fixed to the optical sensors 2 and 24. The first support block 14 or the second support block 30 is placed substantially parallel to the optical fiber 16 of the two optical fibers 16 and 34, and then the first support block 14 or the second support block 30 is moved relative to each other in a first direction perpendicular to the axial direction of the two optical fibers 16 and 34. By moving the second optical fiber 34, the tip of the second optical fiber 34 blocks the light directed from the light output end to the light input end of the pair of optical sensors 26 and 28, so that the optical sensor 2
When the amount of light received at the light incident ends of the optical fibers 6 and 28 attenuates below a predetermined value, the relative movement between the first support block 14 and the second support block 30 is stopped, and then the two optical fibers 16 and 34 are The first support block is moved in a second direction perpendicular to the axial direction of the two optical fibers 16 and 34 and perpendicular to the first direction to a position where the amount of light sent from one to the other is maximum. 14 or a second support block 30 relative to each other to finely adjust the positions of the two optical fibers 16 and 34. 2. The method according to claim 1, wherein the pair of optical sensors 26 and 28 are constituted by a pair of optical fibers, each of which has a core diameter of 80 μm or less.