JPH0346351Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a photodetector fixing device used when calibrating the output level of a photodetector using a measuring device such as an optical power meter. .

[Prior Art] FIG. 7 is a diagram showing an example of a conventional photodetector fixing device.

In this device, a reference photodetector 2 and a photodetector to be calibrated 3 are attached and fixed to a fixed base 1. When calibrating the output level of these photodetectors 2 and 3, the reference photodetector 2 and the photodetector to be calibrated are first detected. An optical fiber 4 is connected to the optical fiber 4, and reference light from an adjustment light source is supplied to the optical fiber 4, and a measuring device 5 measures the level of the electrical signal output from the reference photodetector 2 based on this reference light. The optical power of the adjustment light source is variably adjusted so that the detected value becomes a desired value. In this way, a desired level of reference light is obtained. Then, the optical fiber 4 is removed from the reference photodetector 2 and connected to the photodetector 3 to be calibrated, and the detection signal output from the photodetector 3 to be calibrated based on the reference light from the optical fiber 4 is detected. The sensitivity of the photodetector 3 to be calibrated is adjusted so that the level becomes the desired level described above, and the characteristics of the photodetector 3 to be calibrated are matched with the characteristics of the reference photodetector 2.

[Problems to be solved by the invention] However, in the above-mentioned photodetector fixing device, the state of the light propagating within the optical fiber changes as the optical fiber 4 itself moves due to the operation of changing the optical fiber 4. However, fluctuations occurred in the output level of the optical fiber 4, making it impossible to perform accurate level calibration.

Further, since operations such as securely fixing each of the photodetectors to be calibrated, each having a different shape, to the fixing table 1 are required, there is a problem that it takes time to set the photodetectors to the calibration state.

Therefore, the photodetector fixing device according to the present invention was devised in view of the above-mentioned problems, and its purpose is to provide excellent operability, reduce fluctuations in the output level of the optical fiber, and improve calibration accuracy. An object of the present invention is to provide a photodetector fixing device that can be used to fix a photodetector.

[Means for Solving the Problems] Next, means for solving the above problems will be described with reference to drawings corresponding to embodiments.

That is, the photodetector fixing device of the present invention includes: a base 16; a table 17 provided on the base 16 via a moving mechanism so as to be operable to move linearly in the left-right direction and front-rear direction; and a top surface of the table 17. A first fixing table 23 for removably fixing the reference photodetector 6, which is provided in parallel on one side and the other side with the optical axis direction in the front-rear direction, and a first fixing table 23 for removably fixing the photodetector 7 to be calibrated. a second fixing table 24, whose base end is removably connected to the light source device 11 and whose tip end is connected to the reference photodetector 6 or the photodetector to be calibrated 7;
The front part of the optical fiber 8 which is detachably connected to the
A holding column 19 is detachably fixed on the base 16 so that the optical axis direction of the tip thereof is in the front-rear direction.
and the reference photodetector 6 and the photodetector to be calibrated 7,
Electrical cables 13 and 14 connected to measuring instruments, respectively
It is equipped with and.

The second fixing table 24 has a recess 26 on its upper surface that closely fits the lower part of the photodetector 7 to be calibrated to position and hold it, and also has a recess 26 on its lower surface and the opposite surface of the table 17. are positioning pins 28 that are removably fitted into each other for positioning.
A plurality of mounting holes 27 are provided, and both ends of a belt 17 for fixing and holding the photodetector 7 to be calibrated on the second fixing table 24 are provided on the table 17 on the left and right sides of the second fixing table 24. Attachment member 29 to lock
It is characterized by being provided with.

[Effect] The operation of the above configuration will be explained.

First, the table 17 is moved in the left-right direction and then adjusted in the front-back direction to connect the reference photodetector 6 to the optical fiber 8 so that its optical axis is continuous in the linear direction. The reference light from the light source device 11 is supplied to the optical fiber 8, and the level of the electrical signal output from the reference photodetector 6 is detected based on this reference light, so that the detected value becomes a desired value. The optical power of the adjustment light source is variably adjusted. In this way, a desired level of reference light is obtained.

Next, the optical fiber 8 is removed from the reference photodetector 6, and the table 17 is moved so that the optical fiber 8 is connected to the photodetector to be calibrated so that the optical axis continues in a straight line.
Connect to. After this connection, the characteristics of the photodetector 7 to be calibrated are calibrated to match the characteristics of the reference photodetector 6.

There is no possibility that the state of the light propagating within the optical fiber will change due to movement of the optical fiber 8 itself due to the operation of changing the optical fiber 8 during the above-mentioned work, and that the output level will fluctuate.

In order to calibrate another photodetector 7 to be calibrated, remove the belt 17 and calibrate the other photodetector 7 to be calibrated.
The above operations may be performed by fixing the device on the fixing base 24 of the device. By the way, when the size of the other photodetector 7 to be calibrated is different, another second fixing base 24 having a recess 26 into which the lower part of the other photodetector 7 to be calibrated is tightly fitted is provided. What is necessary is just to use it to fit and fix.

[Example] Fig. 1 is a perspective view showing an embodiment of a photodetector fixing device according to the present invention, Fig. 2 is a plan view of the same device, and Fig. 3 is a sectional view taken along line A-A of the same device. .

The photodetector fixing device in this embodiment is used for calibrating a photodetector installed in an optical power meter, and is configured to position and fix a reference photodetector 6 and a photodetector to be calibrated 7. There is. Each photodetector 6, 7 converts the optical power from the optical fiber 8 into an electrical signal and outputs it.
An optical plug 12 of an optical fiber 8 led from a light source device 11 is selectively connected to optical receptacle sections 9 and 10 provided at the respective input ends. The output end of the reference photodetector 6 is connected to the optical power meter section 11' of the light source device 11 via an electric cable 13. In the light source device 11, reference light is supplied to the reference photodetector 6 through the optical fiber 8, and a detection signal output from the reference photodetector 6 in response to this reference light is measured by the optical power meter section 11'. The output of the light source is adjusted so that this detected value becomes a predetermined level, thereby obtaining reference light at a desired level. Also,
The output end of the photodetector 7 to be calibrated is connected to the electric cable 14.
The optical power meter main body 15 is connected to the optical power meter main body 15 via the optical fiber 8, and a detection signal is supplied to the optical power meter main body 15 based on the optical power from the optical fiber 8.

The photodetector fixing device according to this embodiment is
A holding mechanism that positions and holds the optical fiber 8 on a plate-shaped base 16, a table 17 that positions and holds the reference photodetector 6 and the photodetector to be calibrated 7,
The table 17 is provided with a moving mechanism for moving the table 17 in the front and back and left and right directions of the base 16.

The holding mechanism includes a holding column 1 formed with a holding groove 18 for holding the optical fiber 8 at a predetermined height position from the base 16 by sandwiching the outer jacket part of the optical fiber 8.
It has 9. As shown in FIG. 1, this holding column 19 is erected at the central portion of the base 16 near the front edge. The holding groove 18 is cut from the upper end of the holding column 19, and an arcuate portion 18a for sandwiching the optical fiber 8 is formed in the middle.

Further, a tightening screw 20 is provided on this holding column 19 in the vicinity of the arcuate portion 18a, and by tightening the tightening screw 20, the interval between the holding grooves 18 is adjusted and the optical fiber 8 is attached or detached. It's becoming like that.

One end of the optical fiber 8 is connected to the light source device 11, and the other end is connected to either the reference photodetector 6 or the photodetector to be calibrated 7, and guides light supplied from the light source to the photodetector. The optical fiber 8 is a semi-rigid fiber whose outer periphery is reinforced with a steel flexible pipe 21.
By preventing the optical fiber 8 from wandering during the calibration process, fluctuations in optical power loss within the optical fiber 8 are prevented and a constant output level is maintained. Further, the portion 22 that is touched by the hand when connected to the photodetector is formed of a material with low thermal conductivity such as phenolic resin. Therefore, heat due to body temperature can be prevented from being conducted to the optical fiber, and fluctuations in the light output level can be suppressed.

On the table 17, a first fixed base 23 for mounting the reference photodetector 6 and a second fixed base 24 for mounting the photodetector to be calibrated are arranged side by side.

The first fixing table 23 is disposed on the right side of the table 17 when viewed from the holding mechanism side, and since it holds one type of reference photodetector 6, it is shaped like a U-shape corresponding to the shape of this detector 6. A fixing plate 25 is attached with screws.

The second fixing table 24 is provided to be convertible according to the shape of the detector 7 in order to hold a plurality of types of photodetectors 7 to be calibrated. That is, as shown in FIG. 4, the second fixing base 24 has a recess 26 on the top surface for positioning and holding the photodetector 7, and a plurality of mounting holes 27 are formed on the bottom surface. Table 17 corresponds to
It is designed to be removably attached to a positioning pin 28 provided in the. Further, the recess 26 is formed so that when the photodetector 7 to be calibrated is inserted, its optical axis is aligned with the optical axis of the reference photodetector 6 of the first fixed base 23. .

Therefore, when calibrating the photodetector 7 to be calibrated which has a different shape, it is only necessary to remove the second fixing base 24 from the positioning pin 28 and replace it with a fixing base having a recess corresponding to the other photodetector to be calibrated. The calibration of various types of photodetectors 7 to be calibrated can be easily handled.

The second fixed base 24 is attached to the table 17 by a belt 30 that is stretched around a pair of mounting members 29 provided on the table 17 while holding the photodetector 7 to be calibrated. Positioned and held. Note that one end of the belt 17 is fixed by a hook-and-loop fastener 31 or the like in a state where it is wrapped around the mounting member 29. It is designed to be able to expand and contract as needed.

The moving mechanism includes a slide unit that is moved back and forth with respect to the above-mentioned holding mechanism attached to guide blocks 32 provided on both sides of the base 16, and a lateral guide shaft provided on this slide unit. The table 17 mentioned above is slidably assembled to the table 33.

Each guide block 32 has a length corresponding to the range of movement of the table 17 in the front-rear direction, and has a guide groove 35 formed on its inner surface into which a roller 34 on the slide unit side is rotatably fitted and locked. ing.

The slide unit is constructed by connecting both ends of a pair of guide shafts 33 by a slide piece 36, and a pair of rollers 34 are rotatably supported on each of the slide pieces 36 on both sides. Furthermore, a pair of rollers 37 are rotatably supported on the lower surface of one of the slide pieces 36, and face the upper surface of the base 16. A guide piece 3 is provided on the top surface of the base 16.
8 are disposed close to and parallel to one of the guide blocks 32, and the roller 37 is held between the guide piece 38 and the guide block 32 so as to be freely rotatable. Therefore, the slide unit is restricted from moving in the lateral direction, and can only slide in the longitudinal direction within the range of the guide groove 35 of the guide block 32. Further, one slide piece 36 is provided with a knob 39 for tightening and fixing. This knob 39 is connected to the guide block 3.
The guide block 32 is inserted between the knob 39 and the slide piece 36 by operating the knob 39, and the guide block 32 is inserted between the knob 39 and the slide piece 36. It regulates movement. This makes it possible to prevent displacement of the photodetector during measurement.

Further, the table 17 is slidably assembled to the guide shaft 33 via a plurality of bearings 41 arranged on the lower surface thereof. In other words, each bearing 4
1 is made of synthetic resin, and a guide shaft 33 is inserted therethrough in a tight fit. Note that one pair of such bearings 41 is provided for each guide shaft 33.

The table 17 supported in this manner can be slid laterally along the guide shaft 33, from the position where one bearing 41 abuts one slide piece 36 (the state shown in FIG. 2) to the other position. The side edge moves to a position where it abuts the other slide piece 36 (the state shown in FIG. 5).

As a result, each of the photodetectors 6 and 7 is moved in the front-rear and left-right directions, so that their respective optical axes coincide with the optical axis of the optical fiber 8 fixed to the holding mechanism, and the optical plug of the optical fiber 8 is 12 and the respective receptacle parts 9 and 10 can be connected to each other.

Further, a guide mechanism for regulating the trajectory of the table 17 is provided between the table 17 supported in this manner and the base 16. This guide mechanism is composed of a roller 42 rotatably attached to a substantially central portion of the lower surface of the table 17, and a regulation block 43 arranged in a U-shape on the base 16. In such a block mechanism, while the roller 42 is in contact with one of the outer surfaces of the regulation block 43, the table 17 is moved so that one of the bearings 41 and the slide piece 36 are in contact with each other, as shown in FIG. ing. Therefore, the table 17 can only move in the forward and backward directions in this state. Further, with the roller 42 in contact with the other outer surface of the regulating block 43, as shown in FIG. 5, the other bearing 41 and the slide piece 36 of the table 17 are in contact with each other. Therefore, the table 17 can only move in the forward and backward directions in this state.

Lateral movement of the table 17 becomes possible when the table 17 is retreated to the rearmost position and the roller 42 is in contact with the rear outer surface of the regulation block 43, as shown in FIG. Limited.
Therefore, the movement locus of the table 17 is limited to the U-shape shown by the imaginary line A in FIG. Each photodetector 6, 7 will move only in the axial direction of the fiber 8.
Therefore, when the photodetectors 6 and 7 are attached to and detached from the optical fiber 8, no lateral displacement occurs between them, and damage to the tip of the optical plug 12 can be prevented.

In addition, in the above embodiment, a configuration was described in which the table 17 on which the photodetectors 6 and 7 are mounted is moved in the X-Y direction to align each photodetector 6 and 7 with the optical fiber 8. For example, each photodetector may be positioned and mounted on a rotary table, and alignment with the optical fiber may be performed by rotating the table.

Further, in the above embodiment, a configuration was described in which one reference photodetector 6 and one photodetector to be calibrated 7 are mounted on the common table 17, but a plurality of photodetectors to be calibrated are mounted on the common table 17. The reference photodetector and the photodetector to be calibrated may be provided on separate tables, and each table may be sequentially moved.

[Effect of the invention] As explained above, according to the invention, the table on which the photodetector is mounted is moved by the moving mechanism with respect to the optical fiber fixed by the holding mechanism, and the table on which the photodetector is mounted is moved. Since the configuration is such that the optical fiber and the optical fiber are aligned and connected, there is no need to displace the optical fiber side during calibration work, and fluctuations in the output level due to deformation of the optical fiber or contact with fingers, etc. can be prevented. It is possible to perform highly accurate calibration work.

In addition, each photodetector can be attached to and detached from a fixed optical fiber, and the photodetector can be quickly moved by the moving mechanism, making the calibration easier and faster.

Further, according to the present invention, the second fixing base 2 serves as a holding mechanism for detachably fixing the detector 7 to be calibrated.
4 has a recess 26 on its upper surface that tightly fits with the lower part of the photodetector 7 to be calibrated to position and hold it, and its lower surface and the opposing surface of the table 17 are fitted so that they can be inserted into and removed from each other. It has a structure in which a plurality of positioning pins 28 and mounting holes 27 are provided for positioning, and the photodetector 7 to be calibrated is mounted on the top surface of the photodetector 7 by means of a belt 30, and is integrally mounted on the table 17. Therefore, when calibrating another photodetector 7 to be calibrated having a different size, it is possible to calibrate another second photodetector 7 having a recess 26 large enough to fit tightly into the lower part of the photodetector 7. By using the fixing base 24 and fixing it with the belt 30, it can be accurately and easily fixed at a predetermined position on the table, and the replacement and fixing work of photodetectors to be calibrated of different sizes can be easily and accurately, and the position can be moved. This has the advantage that the calibration work can be carried out easily and accurately.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the photodetector fixing device according to the present invention, Fig. 2 is a plan view of the device, Fig. 3 is a sectional view taken along line A-A of the same device, and Fig. 4 is the same. A partially omitted exploded perspective view showing the second fixing base of the device, FIG. 5 is a plan view of the same device in a state different from FIG. 2, and FIG. 6 is a plan view of the same device in a state different from FIG. 2. FIG. 7 is a plan view showing an example of a conventional photodetector fixing device. 6... Reference photodetector, 7... Photodetector to be calibrated,
8...Optical fiber, 17...Table.

Claims (1)

[Claims for Utility Model Registration] 1. A base 16; a table 17 provided on the base 16 via a moving mechanism so as to be operable to move linearly in the left-right and front-back directions; one side of the top surface of the table 17; A first fixing base 2 that removably fixes the reference photodetector 6, which is provided in parallel with the optical axis direction in the front-rear direction on the other side.
3 and a second fixing base 24 for removably fixing the photodetector 7 to be calibrated; a holding column 19 that detachably fixes the front part of the optical fiber 8 that is detachably connected to the optical fiber 7 on the base 16 so that the optical axis direction of the tip thereof is in the front-rear direction; instrument 6 and photodetector to be calibrated 7
electrical cables 13, which connect these to the measuring instruments, respectively.
The second fixing table 24 has a recess 26 on its upper surface that closely fits the lower part of the photodetector 7 to be calibrated to position and hold it, and the lower surface and the table 17 A positioning pin 28 is provided on the opposing surface of the
A plurality of mounting holes 27 are provided, and both ends of a belt 30 for fixing and holding the photodetector 7 to be calibrated on the second fixing table 24 are provided on the table 17 on the left and right sides of the second fixing table 24. A photodetector fixing device characterized by being provided with a mounting member 29 for locking. 2. The photodetector fixing device according to claim 1, wherein a plurality of the second fixing stands 24 are arranged in parallel.