JP2007033283A - Sleeve splicing loss measuring device, and splicing loss measuring method using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect the maximum value of splicing loss of a sleeve by providing a rotation means for rotatably supporting a cylindrical sleeve in the circumferential direction and measuring the splicing loss of light of the sleeve continuously at all rotation angles while being rotated in a state where the stub is inserted in the sleeve. <P>SOLUTION: A sleeve splicing loss measuring device comprises inserting a first stub 5a from one end of a through hole of the cylindrical sleeve 10, inserting a second stub 5b from the other end of the through hole of the sleeve 10, optically splicing a first optical fiber 4a and a second optical fiber 4b, and measuring light loss of the sleeve 10. The sleeve splicing loss measuring device supports the outer periphery of the sleeve 10 and is provided with the rotation means 3 for rotating the sleeve 10 in the circumferential direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a measuring apparatus and a measuring method for measuring a connection loss of light of a sleeve used for an optical connector or the like used for connecting an optical fiber.

As shown in FIG. 7, an optical connector for connecting optical fibers is formed by inserting a pair of ferrules 41 having optical fibers 40 inserted into through holes from both ends of an optical communication split sleeve (hereinafter simply referred to as a sleeve) 10. The front end surfaces are butted and optically coupled.
However, if the dimensional accuracy of the sleeve 10 used at this time is not excellent, it will be understood that, when the tip surfaces of the pair of ferrules 41 are brought together, a center misalignment or the like occurs, resulting in an optical connection loss. ing.

  Therefore, in order to prevent the provision of the sleeve 10 that causes such optical connection loss, the optical connection loss of the sleeve is measured using the half adapter 12a before being incorporated into the optical connector. .

  This center misalignment is caused by the outer diameter roundness of the ferrule 41 and the inner diameter roundness of the sleeve 10, and particularly the inner diameter roundness of the sleeve 10 has a great influence, and the connection loss has changed greatly. . That is, even in the same sleeve 10, the light loss value varies depending on the rotation angle of the inner diameter in the circumferential direction.

  Therefore, when measuring the light loss of the sleeve 10, for example, the sleeve 10 is rotated at 0 °, 90 °, 180 °, and 270 ° with respect to a certain reference axis, and the light loss value is obtained at four points. The value with the largest loss value was measured as the optical connection loss value of the sleeve.

  However, in the above conventional measurement method, the light loss value of the sleeve 10 is measured only from the four points described above. Therefore, from 0 ° to 90 °, 90 ° to 180 °, 180 ° to 270 °, and 270 ° When there is a maximum connection loss value between the measurement points as in 360 ° (0 °), the optical connection loss value could not be measured accurately. Therefore, when measuring the true loss value, it is necessary to measure a plurality of points. However, the rotation of the sleeve 10 is performed in a state where the stubs are separated from each other so that the fiber end faces of the stubs are not rubbed and damaged. Therefore, it is necessary to repeat these cycles of stub separation, sleeve 10 rotation, stub contact, and optical connection loss measurement, and much time is required for the measurement.

  Therefore, the present invention has been made in view of the above problems, and includes a first light source, a first optical fiber connected to the light source, and a through hole into which the first optical fiber is inserted. A cylindrical sleeve comprising: a stub; an optical power meter; a second optical fiber connected to the optical power meter; and a second stub having a through hole into which the second optical fiber is inserted. The first stub is inserted from one end of the through hole of the sleeve, the second stub is inserted from the other end of the through hole of the sleeve, and the first optical fiber and the second optical fiber are optically coupled. A sleeve connection loss measuring device for measuring the optical loss of the sleeve by connecting them in a continuous manner, characterized in that it has a rotating means for rotatably supporting the sleeve in its circumferential direction.

  In addition, the first stub includes a first holding member that holds the outer periphery thereof, and the second stub includes a second holding member that holds the outer periphery thereof.

  Furthermore, the movable holding stage which mounts the said 1st holding member and / or the said 2nd holding member so that a movement is possible is characterized by the above-mentioned.

  Further, light is introduced from the light source into the first optical fiber, the first stub is inserted from one end side of the through hole of the sleeve, and the second stub is inserted into the other end side of the through hole of the sleeve. The first optical fiber and the second optical fiber are optically coupled, and the sleeve is led out from the second optical fiber while rotating the sleeve in the circumferential direction by the rotating means. The light is detected by the optical power meter, and the light connection loss of the sleeve is measured.

  The first stub may be optically coupled with being separated from the second stub.

  According to the sleeve measuring apparatus of the present invention, by providing the rotating means for rotatably supporting the cylindrical sleeve in the circumferential direction, the sleeve is rotated while the stub is inserted into the sleeve. Since it is possible to continuously measure the optical connection loss of the sleeve at the rotation angle, the maximum value of the optical connection loss of the sleeve can be accurately detected. Therefore, it is possible to easily determine whether the sleeve is good or defective.

  In addition, by rotating the sleeve while separating the stubs inserted into the sleeve, it is possible to prevent friction due to contact between the tip surfaces of the stubs and to prevent damage to the fibers on the end surfaces of the stubs. Thus, the optical connection loss value of the sleeve can be measured in a short time with higher accuracy.

  Hereinafter, an embodiment of a sleeve connection loss measuring apparatus according to the present invention will be described. FIG. 1 is a cross-sectional view showing an embodiment of a sleeve connection loss measuring apparatus according to the present invention.

  As shown in FIG. 1, the sleeve connection loss measuring apparatus includes a light source 1, an optical power meter 2, a rotating means 3, and an optical fiber 4 (first optical fiber 4a and second optical fiber 4b) inserted into a through hole. ) Stub 5 (first stub 5a, second stub 5b), holding member 6 (first holding member 6a, second holding member 6b), adapter 7, and movable stage 8.

  The light source 1 includes an LD (laser diode) and the like, and has a function of introducing light emitted from the LD into an optical fiber 4 a connected to the light source 1. The wavelength of light emitted from the LD light source is not particularly limited, and is preferably 1310 nm or 1510 nm depending on the use of the optical fiber.

  As shown in FIG. 2, the optical power meter 2 includes a light receiving unit 2a and a calculation unit 2b. The light source 2a detects light emitted from the LD light source 1 and transmitted through the optical fiber 4, and the calculation unit. By processing in 2b, the amount of light loss is measured. Here, the light loss amount is calculated by comparing the light amount P0 output from the light source 1 with the light amount P1 received by the light receiving unit 2a of the optical power meter 2, and the light connection loss IL is expressed as IL = Log10 (P1 / P0). ) And measured.

  Further, the optical power meter 2 has a third optical fiber 4c optically coupled to the second optical fiber 4b in the through hole in order to receive light transmitted from the second optical fiber 4b. A master stub 9, a third holding member 6 c for holding the master stub 9, and an adapter 7 that enables the holding member 6 c to move in the optical axis direction are provided. Here, since the light receiving unit 2a is connected to the third optical fiber 4c, it can receive light transmitted from the first and second optical fibers.

  The rotating means 3 supports the cylindrical sleeve 10 into which the first stub 5a and the second stub 5b are inserted and rotates the sleeve 10 in the circumferential direction. As a form of supporting the sleeve 10, for example, one rotating means 3 is arranged below the sleeve 10, and the peripheral surface of the rotating means 3 and the outer peripheral surface of the sleeve 10 are brought into contact with each other and supported. Each of the peripheral surfaces of the means 3 and the outer peripheral surface of the sleeve 10 may be brought into contact with each other while being supported. As shown in FIG. 6, the rotating means 3 has a structure in which the rotating means 3 is driven by attaching a cylindrical support 3a and an elastic ring 3b to the outer peripheral surface thereof and rotating the shaft 3c. . The shaft 3c is connected to a power source for rotating the rotating means 3, for example, a stepping motor, and drives the rotating means 3 in the rotation direction. As the material of the elastic ring 3b, silicon rubber, acrylic rubber, nitrile rubber, or the like can be used, and the softness is preferably 20 to 40 degrees. The rotating means 3 is fixed by joining the shaft 3c to a support (not shown). As another form of supporting the sleeve 10, it is possible to adopt a configuration in which the sleeve 10 is rotated while the both end surfaces of the sleeve 10 are supported by being sandwiched by the peripheral surfaces of at least two rotating means 3.

  Further, the roundness of the outer periphery of the elastic ring 3b is preferably 100 μm or less. This is because when the roundness exceeds 100 μm, it becomes difficult to efficiently rotate the object to be measured, and an error may occur in the measurement of the optical connection loss. If the contact surface of the rotating means 3 with the sleeve 10 is made to have a surface roughness Ra of 10 to 100 μm, the sliding between the rotating means 3 and the sleeve 10 is prevented and the frictional resistance at the contact surface is increased. Since it can suppress, the sleeve 10 can be rotated efficiently.

  The stub 5 is made of a material such as ceramic, resin, or glass, has a cylindrical shape, and is configured by holding the optical fiber 4 in the through hole. The stub 5 optically couples a plurality of optical fibers. Here, the first stub 5a is inserted from the opening portion on one end side of the sleeve 10, while the other end side of the sleeve 10 is inserted. By inserting the second stub 5b into the sleeve 10 from the opening portion, the first optical fiber 4a and the second optical fiber 4b are optically coupled within the sleeve 10.

  The holding member 6 (first holding member 6a, second holding member 6b) is a member that optically accurately connects the first stub 5a and the second stub 5b, and as shown in FIG. While being press-fitted into the metal fitting 11, it is held in the holding member 6 by a spring 12 with a predetermined spring force. For this reason, when the stubs come into contact with each other, the optical fibers 4 are pressed against each other by the force of the spring and are in close contact with each other, so that the connection loss of light can be efficiently reduced. The spring force at this time is preferably 1.96N to 5.88N. Further, as the material of the holding member 6, nylon resin, liquid crystal polymer resin, polyacetal resin, polybutylene terephthalate resin, polyetherimide resin and polycarbonate resin are desirable, and for example, they can be produced by an injection molding method or the like.

  The adapter 7 has a function for fixing the first stub 5a and the second stub 5b held by the two holding members 6a and 6b at positions where they can contact each other, and the material thereof is nylon resin. A liquid crystal polymer resin, a polyacetal resin, a polybutylene terephthalate resin, a polyetherimide resin, and a polycarbonate resin are desirable and can be produced by, for example, an injection molding method.

  The movable stage 8 is placed in contact with the lower surface of the adapter 7 having the holding member 6, has a function of accurately positioning the holding members 6, and can adjust the height and the left and right positions. At the same time, the distance between the adapters 7 can be controlled in units of 1 μm.

  According to the sleeve connection loss measuring apparatus of the present invention, since the rotation means 3 that enables the sleeve 10 to rotate in the circumferential direction is provided, the first stub 5 a and the second stub 5 b are attached to the sleeve 10. Since it is possible to continuously measure the light connection loss of the sleeve 10 at all rotation angles while rotating the sleeve 10 in the inserted state, the maximum value of the light connection loss of the sleeve 10 can be accurately determined. Can be detected. Therefore, it is possible to easily determine whether the sleeve 10 is good or defective.

  Moreover, since the stub 5 can be held in the optical axis direction by holding the outer periphery of the stub 5 with the holding member 6, the stub 5 can be smoothly inserted into the sleeve 10, and Connection loss can be reduced.

  Next, a sleeve connection loss measuring method using the sleeve connection loss measuring apparatus of the present invention will be described.

  First, zero correction of the connection loss measuring device is performed. This zero correction measures the connection loss of light generated in the optical system connecting the light source 1 and the power meter 2, and calculates the connection loss value of light generated in the optical system from the actually measured connection loss value of the sleeve light. By reducing, the optical connection loss value of the sleeve can be accurately calculated.

  In the zero correction, as shown in FIG. 4, a master having a first stub 5 a having a first optical fiber 4 a connected to the light source 1 and a third optical fiber 4 c connected to the optical power meter 2 is used. The stub 9 is inserted from the opening portion on one end side and the opening portion on the other end side of the cylindrical master sleeve 13 whose inner diameter roundness is processed with high accuracy, and the first stub 5a and the master are inserted. The stub 9 is held by the master sleeve 13 so as to be optically coupled.

Then, the light is output from the light source 1 with the light amount P0, the light transmitted from the optical fiber is received by the optical power meter 2, the minimum value (P1) of the light amount of the received light is measured, and the optical system described above calculating the maximum connection loss value IL ₁ of the light from _{IL 1 = Log10 (P1 / P0} ) occurring. The obtained IL ₁ value is a connection loss value of light generated between the light source 1 and the power meter 2, and this IL ₁ value (zero correction value) is subtracted from the light connection loss IL of the sleeve 10 described later. Thus, the light connection loss value of the sleeve 10 can be accurately calculated.

  Next, a method for measuring the optical connection loss of the sleeve 10 that is the object to be measured will be described. As shown in FIG. 5, the first stub 5a is removed from the master sleeve 13, and a master jumper including a second stub 5b and a third stub 5c sharing the second optical fiber 4b is prepared. The stub 5c is inserted and fixed to the adapter 7 via the third holding member 6c, and the third stub 5c is inserted from the opening on one end side of the master sleeve 13, and the third stub 5c and the master stub 9 are connected. It fixes with the master sleeve 13 so that it may couple | bond together optically.

  Next, each adapter 7 is moved to the movable stage 8 so that the first stub 5a and the second stub 5b fixed to the adapter 7 via the first holding member 6a and the second holding member 6b face each other. Position with. The opposing accuracy at this time may be set so as to fall within a range of about ± 1 mm in each direction.

  Next, the sleeve 10 that is the object to be measured is inserted into one end of the cylindrical stub 5 at one end of the first stub 5a or the second stub 5b, and then movable. The stage 8 is moved, and one end portion of the stub 5 not inserted in the sleeve 10 is inserted into the opening portion on the other end side of the sleeve 10, and the first stub 5 a and the second stub 5 b are inserted in the sleeve 10. Are coupled, that is, the first optical fiber 4a and the second optical fiber 4b are optically coupled. At this time, the first stub 5a and the second stub 5b are separated from each other in the sleeve 10 so that the connection loss of light between the first optical fiber 4a and the second optical fiber 4b is about 0.5 dB. It is preferable to arrange. This is because the end faces of the first stub 5a and the second stub 5b are brought into contact with each other in order to make the connection loss of light between the first optical fiber 4a and the second optical fiber 4b smaller than 0.5 dB. This is because, in such a case, if the sleeve 10 is rotated, the fibers exposed on the end face of the stub are damaged, and the optical connection loss value of the sleeve 10 may not be measured accurately.

  Next, light is output from the light source 1 with a light amount P0, the rotating means 3 is brought into contact with the sleeve 10, and the rotating means 3 is rotated to rotate the sleeve 10 so as to rotate once in the circumferential direction of the inner diameter. . The rotation speed at this time is preferably 10 to 20 rpm.

Then, the light transmitted through the optical fiber is received by the optical power meter 2 while rotating the sleeve 10, and the amount of light detected by the light receiving unit 2a is continuously measured. The plurality of measured values obtained here indicate the amount of light at various rotation angles of the sleeve 10, and the minimum value of the measured amount of light is P2. Further, the maximum value IL ₂ of the light connection loss value of the sleeve 10 is calculated from P ₂ by IL ₂ = Log 10 (P ₂ / P 0). However, the IL ₂ has a value including a connection loss of light generated when the light source 1 and the power meter 2 are connected. Therefore, the true loss value IL is calculated from IL = IL ₂ −IL ₁ = Log 10 (P2 / P1) using the optical connection loss IL ₁ measured by the above-described zero correction, and the true light of the sleeve 10 is calculated. Measure the connection loss value.

  According to the above-described method, in the present invention, it is possible to continuously measure the connection loss of light that fluctuates depending on the rotation angle of the sleeve 10, so that the maximum value of the connection loss of light of the sleeve can be accurately detected. it can.

  Examples of the present invention will be described below. The LD light source 1 is connected to the stub 5a via the first optical fiber 4a. The stub 5 is press-fitted into the metal fitting 11 and is incorporated in the first holding member 6 a together with the spring 12. Similarly, the optical power meter 2 is also provided with a stub 5b connected via an optical fiber 4b. The stub 5 is press-fitted into the metal fitting 11, and is incorporated into the first holding member 6a together with the spring 12. It is. These holding members 6 are fixed to the movable stage 8 by an adapter 7, and by moving the movable stage 8, one end of each of the first stub 5 a and the second stub 5 b is inserted from the opening end of the sleeve 10. The position adjustment is possible so that the end surfaces of the first stub 5a and the second stub 5b face each other. Further, in order to rotate the sleeve 10 in the circumferential direction, the rotating means 3 composed of a cylindrical support 3 a having an elastic ring 3 b on the outer peripheral surface is supported by a support so as to come into contact with the peripheral surface of the sleeve 10. The sleeve connection loss measuring apparatus according to the embodiment of the present invention is configured.

  Further, nitrile rubber having a softness of 30 degrees was used for the elastic ring 3b, and the roundness of the outer periphery was 50 μm. The stub 5 is a cylindrical body made of zirconia ceramics and has a diameter of 2.5 mm and a length of 10 mm. The optical fiber 4 is fused to the inner hole. The LD light source used was one manufactured by JDS FITEL (model number RM8750B), while the optical power meter was manufactured by HEWLETT PACKARD (model number 8153). Furthermore, the holding member and the adapter were produced by injection molding using a polyacetal resin.

  Next, the sleeve 10 as the object to be measured was made of zirconia ceramics and had a cylindrical shape having a length of 11.4 mm, an outer diameter of 3.2 mm, and an inner diameter of 2.5 mm.

  And the measurement method of this invention as shown below and the measurement method of the comparative example were compared and examined. In both the example and comparative example of the present invention, ten sleeves 10 were prepared, the output wavelength from the light source was set to 1350 nm, and the optical connection loss of the sleeve 10 was measured.

  First, in the embodiment of the present invention, the first stub 5a and the second stub 5b are inserted separately in the through hole of the sleeve 10 so that the optical connection loss is 0.5 dB, and the rotating means 3 The rotation speed is set to 15 rpm, the connection loss of light is measured with the power meter 2 while rotating the sleeve 10 in the circumferential direction, and the rotation angle with the largest connection loss of light is found. Then, the maximum light loss value of the sleeve 10 was measured by bringing the first stub 5a and the second stub 5b into contact with each other at the rotation angle. Furthermore, the time spent for the measurement was recorded as the elapsed time.

  Further, as Comparative Example 1, a sleeve 10 is used in a state where the first stub and the second stub are separated from each other by using a measuring device that does not include the rotating means 3 of the sleeve connection loss measuring device according to the embodiment of the present invention. Are rotated manually at 0 °, 45 °, 90 °, 135 °, 180 °, 225 °, 270 °, 315 °, 360 ° and every 45 °, and the first rotation angle is set to the first angle. The stub and the second stub were brought into contact with each other to measure the optical connection loss value, and the maximum value of the optical connection loss value obtained at the rotation angle was calculated. Furthermore, the time spent for the measurement was recorded as the elapsed time.

  Further, as Comparative Example 2, a measurement device that does not include the rotation means 3 of the sleeve connection loss measurement device according to the embodiment of the present invention is used, and the sleeve 10 is manually rotated to 0 °, 90 °, 180 °, Rotating at 270 °, 360 °, and 90 °, the first stub and the second stub were brought into contact with each other at the rotation angle described above, and the connection loss value of the light was measured, and obtained at the rotation angle. The maximum value of the optical connection loss was calculated. Furthermore, the time spent for the measurement was recorded as the elapsed time.

Furthermore, after zero correction was applied to the optical connection loss values calculated in the examples of the present invention and Comparative Examples 1 and 2 of the present invention, the values are shown in Table 1. The results are shown in Table 1.

  As shown in Table 1, when the optical connection loss value of the sleeve 10 is compared, in Comparative Example 2, there are only four measurement points of the optical connection loss value, and the optical connection loss value can be accurately calculated. Since it was not possible, an error was generated in comparison with the connection loss value of light measured in the example of the present invention and Comparative Example 1.

  In Comparative Example 1, the number of measurement points of the optical connection loss value is as many as 8 points. Further, every time the rotation angle of the sleeve 10 is changed, it is necessary to separate the stubs 5 inserted into the sleeve 10. Therefore, the elapsed time spent for measurement increased.

  On the other hand, in the embodiment of the present invention, it is possible to continuously measure the light connection loss value of the sleeve 10 while rotating the sleeve 10 by the rotating means 3. Thereby, since the measurement point of the optical connection loss value can be increased, the optical connection loss value of the sleeve 10 can be accurately measured. Furthermore, since it is not necessary to take out the stub 5 from the sleeve 10, the elapsed time spent for the measurement can be greatly shortened.

It is sectional drawing which shows the connection loss measuring apparatus of the sleeve of this invention. It is explanatory drawing for demonstrating the optical power meter used for the connection loss measuring apparatus of the sleeve of this invention. It is sectional drawing which shows the connection structure of the stub used for the connection loss measuring apparatus of the sleeve of this invention. It is explanatory drawing for demonstrating the connection loss measuring method of the sleeve of this invention. It is sectional drawing for demonstrating the connection loss measuring method of the sleeve of this invention. It is a side view of the rotation means used for the connection loss measuring apparatus of the sleeve of the present invention. It is sectional drawing which shows the structure of the optical connector which connects optical fibers.

Explanation of symbols

1: Light source 2: Optical power meter 2a: Light receiving unit 2b: Calculation unit 3: Rotating means 3a: Support body 3b: Elastic ring 3c: Shaft
5: Stub
5a: First stub
5b: second stub 5c: third stub 6a: first holding member 6b: second holding member 6c: third holding member 7: adapter 8: movable stage
9: Master stub 10: Sleeve to be measured 11: Metal fitting
11: Spring 13: Master sleeve 14: Contact connector 15: Optical power meter side adapter 40: Optical fiber 41: Stub

Claims (5)

A light source, a first optical fiber connected to the light source, a first stub having a through-hole into which the first optical fiber is inserted, an optical power meter, and a first optical fiber connected to the optical power meter 2, and a second stub having a through hole into which the second optical fiber is inserted, the first stub is inserted from one end of the through hole of the cylindrical sleeve, and the sleeve The second stub is inserted from the other end of the through hole of the first optical fiber, and the first optical fiber and the second optical fiber are optically connected to measure the light connection loss of the sleeve. A connection loss measuring device,
A sleeve connection loss measuring apparatus comprising a rotating means for rotatably supporting the sleeve in its circumferential direction.   The sleeve according to claim 1, wherein the first stub includes a first holding member that holds an outer periphery thereof, and the second stub includes a second holding member that holds the outer periphery thereof. Connection loss measuring device.   The sleeve connection loss measuring apparatus according to claim 1, further comprising a movable stage on which the first holding member and / or the second holding member are movably mounted. A sleeve connection loss measuring method using the sleeve connection loss measuring device according to claim 1,
Light is introduced from the light source into the first optical fiber, the first stub is inserted from one end side of the through hole of the sleeve, and the second stub is inserted from the other end side of the through hole of the sleeve. Then, the first optical fiber and the second optical fiber are optically coupled, and the light derived from the second optical fiber while rotating the sleeve in the circumferential direction by the rotating means. Is measured by the optical power meter, and the connection loss of the sleeve is measured.   The sleeve connection loss measurement method according to claim 4, wherein the first stub is optically coupled with being separated from the second stub.

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