JP2002328011A - System and method for measuring displacement of plural points - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for measuring displacement of plural points, which can simultaneously measure the amount of displacement at a low cost even in the case the plural points are in close proximity to each other, has little restriction for arranging optical parts, has little measurement error, has a broad measurement range, and has high responsibility. SOLUTION: The system for measuring displacement of plural points is composed of optical fibers 4a, 4b,..., 4n, a plurality of semiconductor lasers 2a, 2b,..., 2n emitting laser light, semiconductor laser drivers 1a, 1b,..., 1n exciting the semiconductor lasers, and a semiconductor device for detecting position 10 which detects light current generated by the laser light focused on a photo- detecting surface through a condensing lens 9. Drive pulses are in turn sent to the semiconductor laser drivers 1a, 1b,..., 1n from a control section 11, and the semiconductor lasers 2a, 2b,..., 2n cyclically emit the laser light. At least, one among the condensing lens, the semiconductor device for detecting position and the light emitting edge of each optical fibers is installed at an object to be measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting a plurality of optical fibers, a condenser lens, and a semiconductor position detecting element on an object to be measured, and sequentially sending drive pulses to cause a pulse light source to emit light cyclically. The present invention relates to a multi-point displacement measuring device for measuring the displacement of a plurality of measurement points by detecting the light spot position of emitted light with a semiconductor position detecting element, and to a multi-point displacement measurement method for measuring the displacement of a plurality of measurement points.

[0002]

2. Description of the Related Art Conventionally, as a means for measuring or measuring the displacement, the moving distance, the displacement amount, or the deformation amount of an object moving or deforming at high speed, a number of measuring devices having different principles have been proposed. Have been. For example, an electrical measuring means for detecting a change in electric resistance or a change in capacitance, a change in inductance by using eddy current or the like, or a magnetic method for detecting using a magnetoelectric conversion element such as a Hall element. There are a large number of devices having different principles, such as a measuring device, a measuring device using an elastic wave, and a measuring device using light such as a laser interferometer. However, all of them are expensive, have problems in high-speed response, and measurement range, and in many cases, high reliability cannot be expected with respect to accuracy. For example, in tensile test equipment and impact tensile test equipment, it is expected to measure displacement from small amplitude to large amplitude under various load speeds from static load to impact load. There is currently no device that covers the area with high precision.

[0003] Therefore, the present inventors have proposed
The following displacement measuring device was proposed.
See A, 63-611.p1431 and A, 64-628.p2975). sand
In other words, a light and flexible optical fiber end
Laser light emitted from this optical fiber
The light of the source is condensed by a lens, and the PSD (Position Sensing
tector) sensor. In addition, this PS
D sensor is P layer, N ⁺Layer, N⁻Consists of three layers
A semiconductor position detecting element, which is a light spot on a light receiving surface of incident light.
Difference in photocurrent output of output terminal depending on position
The displacement is measured based on the following equation. And this
1 μsec or less for PSD sensor (hereinafter, semiconductor position detecting element)
It has a response speed of lower to several tens of microseconds, and moves and changes at high speed.
It is possible to directly measure the actual displacement of the measuring object
Wear.

Since displacement can be measured by each semiconductor position detecting element, if two sets of a laser light source, an optical fiber, and a semiconductor position detecting element are provided in parallel, the displacement amount, deformation amount or elongation between two points can be naturally determined. It becomes possible to measure. Displacement measurement devices that can measure this displacement can measure the displacement up to a large strain range that exceeds the measurement limit of the strain gauge, compared to strain gauges, etc.
In addition, since the measurement is performed substantially in a non-contact manner, noise is less likely to enter, and the reliability is high.

A displacement measuring device and a displacement measuring device (hereinafter, a displacement measuring device including a displacement measuring device in a broad sense including the displacement measuring device) using the semiconductor position detecting element are operated in addition to the dynamic characteristics of the semiconductor position detecting element. The dynamic characteristics of the amplifier circuit are also affected, and the above-described semiconductor position detecting element has a high response speed. Therefore, the overall dynamic characteristics generally depend on the dynamic characteristics of the operational amplifier circuit. Therefore, it is necessary to employ an operational amplifier having good responsiveness. The conventional displacement measuring device proposed by the present inventors has succeeded in setting the frequency response to 100 kHz.

Therefore, a conventional displacement measuring device proposed by the present inventors will be described below. FIG. 5 is a configuration diagram of a conventional displacement measuring device, FIG. 6 is an explanatory diagram of measurement of a light spot position by a conventional semiconductor position detecting element, and FIG. 7 is a displacement amount diagram measured by a conventional displacement measuring device.

In FIG. 5, reference numeral 41 denotes a power supply section for providing a semiconductor laser driver, connecting a power supply when oscillating the semiconductor laser, and disconnecting the power supply after measurement.
Reference numerals 41a and 41b denote power switches constituting the power on / off section 41, and reference numerals 42a and 42b denote semiconductor lasers which are connected to a power source by the power switches 41a and 41b and oscillate continuously.
The semiconductor lasers 42a and 42b output light having a wavelength in the visible region in consideration of the eyes.

Reference numerals 43a and 43b denote semiconductor lasers 42a and 4b.
A micro lens 44 for condensing the light emitted from 2b, 44
Reference numerals a and 44b denote optical fibers for transmitting the light condensed by the microlenses 43a and 43b, and reference numerals 45a and 45b denote the light source side end surfaces of the optical fibers 44a and 44b by the microlenses 43a and 43b.
This is an FC type optical fiber connector (F01 type single core optical fiber connector specified in JIS C5970) which is securely disposed near the focal point of 43b. The FC optical fiber connectors 45a and 45b and the micro lenses 43a and 43b
Has a configuration in which the end faces of the optical fibers 44a and 44b can be securely fixed at predetermined positions, and the optical fibers 44a and 44b can be easily attached and detached. This makes it possible to adjust the intensity of the laser light incident on the optical fibers 44a and 44b by taking the optical fibers 44a and 44b in and out. Further, when the ratio of incident light is reduced due to deterioration of the end face, this can be dealt with by polishing the end face.

Reference numeral 46 denotes an object to be measured such as a tensile test material;
a and 47b are optical fibers 44 with respect to the object 46 to be measured.
a, an attachment member such as an adhesive tape (for example, an adhesive tape) for fixing the emission-side end of 44b. The attachment members 47a and 47b are fixed with care so that the light emitted from the optical fibers 44a and 44b is directed in a predetermined direction. 48
Are power switches 41a and 41 for oscillating a laser.
b is a power supply unit for supplying a drive voltage to the semiconductor lasers 42a and 42b by b.

The optical fibers 49a, 49b are optical fibers 44a, 4b.
A prism which receives the light emitted from the light source 4b and bends the optical axis of each light in a right angle direction, and 50a and 50b are condensing lenses for condensing and focusing each light. These are two optical fibers 44 at a very close distance.
This is necessary in order to simultaneously measure the light emitted from the light emitting side ends of the light emitting devices a and 44b. 51a and 51b are one-dimensional semiconductor position detecting elements, and condensing lenses 50a and 50b
Thus, the position of the light spot focused on the light receiving surface can be measured by the magnitude of the photocurrent. This will be described later.

Reference numeral 52 denotes a microprocessor or the like.
A control unit 53 for controlling the displacement measuring device includes an output from the semiconductor position detecting element 51a and a semiconductor position detecting element 51b.
And an output from the operational amplifier 53. The operational amplifier 54 is also capable of calculating the respective coordinate positions (displacements) from the respective light spot positions and calculating the displacement from the difference between the two. Sampling means 55 for sampling an analog signal;
A memory unit for recording the converted data, 56 is a clock unit for sampling by the sampling unit 54, and 57 is a display unit such as a display for displaying the output obtained by the sampling unit 54 or an analog voltage output on the screen as the case may be. Things.

The measurement principle of the above-described conventional displacement measuring device will be described with reference to FIGS. 6, the output terminal 61 is a light receiving surface of the semiconductor position detecting element 51a to cause photoelectric conversion when receiving light, 62a, 62b are respectively receives the light and outputs the photocurrent _{I x1, I x 2,} 6
3 is a condenser lens 5 for emitting light from the optical fibers 44a and 44b.
The light spot position focused on the light receiving surface by 0a and 50b, and 64 is an intermediate position on the light receiving surface 61 at the same distance from the output terminals 62a and 62b. Although the semiconductor position detecting element 51a is shown in FIG. 6, the semiconductor position detecting element 51b is also identical, though not shown. The distance between the intermediate position 64 and each of the output terminals 62a and 62b is L, and the distance between the intermediate position 64 and the light spot position 63 is x. When the light spot position 63 is at the intermediate position 64, x = 0,
Output terminals 62a, no difference in photocurrent _{I x1, I x2} from 62b. Generally, when the photocurrents _Ix1 and _Ix2 are detected, the position x of the light spot position 63 is expressed by (Equation 1).

[0013]

(Equation 1) Therefore, when this operation is performed by the operation amplification unit 53, it is possible to measure where the emission-side ends of the optical fibers 44a and 44b attached to the measurement object 46 by the attachment members 47a and 47b. As can be seen from (Equation 1),
When the intensity of light incident on the semiconductor position detecting element changes, that is, when the photocurrents I _x1 and I _x2 change at the same rate,
The change in light amount is canceled by the numerator and denominator, and the light spot position 6
The position x of 3 shows the same value.

In the conventional displacement measuring apparatus described above, both the semiconductor lasers 42a and 42b are continuously oscillated, the sampling timing is measured by the clock means 56, and the displacement at a predetermined time and the displacement after a predetermined time are measured. It was to be measured. The semiconductor position detecting element 51a, photocurrent 51b detects _{I x1, I x2} sampling means 54
Sampled, and the sampled photocurrent I _x1 ,
The light spot position 63 of _Ix2 is calculated by the operational amplifier 53 and recorded in the memory 55.

The displacement of the light spot position 63 corresponding to the position of the exit side of the optical fibers 44a and 44b of the measurement object 46 calculated by the operational amplifier 53 is as shown in FIG. However, in FIG. 7, the displacement line is shown after being converted into a calibrated actual displacement amount. 67 is a semiconductor laser 42
a displacement line of the light spot position 63 of the semiconductor laser 42a in which the light spot position 63a is plotted with respect to the time course;
Is a displacement line of the light spot position 63 of the semiconductor laser 42b in which the change of the light spot position 63 of the semiconductor laser 42b is plotted with respect to time. It can be seen that both changes linearly. In FIG. 7, the difference on the x-axis between the displacement lines 67 and 68 is the distance on the light spot position 63 of the semiconductor lasers 42a and 42b, which is the optical fibers 44a and 44.
This corresponds to the distance of the output end position b. That is, the semiconductor laser 4 when it from time _{t 1} to time _{t 2}
The fact that the distance between the light spot positions 63 of 2a and 42b is slightly reduced indicates that the displacement amount occurs at the emission side end.

In the conventional displacement measuring device proposed by the present inventors, since the semiconductor lasers 42a and 42b only oscillate continuously, the driving portion can be easily manufactured.
Since the use of the prisms 49a and 49b makes the device relatively expensive, the present inventors place a half mirror on the optical axis of the semiconductor position detecting elements 51a and 51b instead of the prisms 49a and 49b, and divide it into two. The semiconductor position detecting element 51a directly measures the other plurality of lights,
An optical fiber 44 is used for the other plurality of divided lights.
A modified displacement measuring device which shields only b, detects the light spot position of the optical fiber 44a by the semiconductor position detecting element 51b, and performs an operation based on this to determine the displacement of the optical fiber 44b has been proposed again.

As a result, the two lights of the optical fibers 44a and 44b enter the light receiving surface of the semiconductor position detecting element 51a, and the photocurrents I _x1 and I _{x2 convert} the two lights into one light. This indicates an output corresponding to the position of the center of gravity of the light intensity when considered. Therefore, by using this position of the center of gravity, the position of the optical fiber 44b can also be calculated from the light spot position of the optical fiber 44a detected by the semiconductor position detecting element 51b. However, the re-proposed displacement measuring device also basically includes the semiconductor lasers 42a and 42b, the optical fibers 44a and 44b, and the semiconductor position detecting elements 51a and 51b.
Two sets of optical measurement systems, such as b, are required, and this is the same as the above-described conventional displacement measurement apparatus. Further, in order to measure displacements at three or more points, it is necessary to increase the number of optical measurement systems such as the above-mentioned half mirrors and perform similar measurements.

[0018]

The conventional displacement measuring device proposed by the present inventors as described above uses a semiconductor laser 42a, an optical fiber 44a, a semiconductor position detecting element 51a, Two sets of the laser 42b, the optical fiber 44b, and the semiconductor position detecting element 51b, so to speak, two sets of displacement measuring devices were provided for measurement. Certainly, since the semiconductor lasers 42a and 42b are only continuously oscillated, it is easy to manufacture a laser driving portion. However, the cost of the displacement measuring device is high and the structure is complicated, so that there are practically three or more points. A multipoint displacement measuring device for a point position is not practical.

The biggest problem of the conventional displacement measuring device is that the prism 49 which bends each light at right angles so that the light from the optical fibers 44a and 44b can be measured.
a, 49b, which is the point that condensing lenses 50a, 50b for condensing and focusing each light are required. They are,
To measure the displacement difference between two points at a close distance,
This is necessary due to restrictions on the arrangement of optical components. That is, two light collecting lenses 50a and 50b are required to collect light emitted from the two optical fibers 44a and 44b, but the size of the light collecting lenses 50a and 50b and the holder are finite. And the condenser lenses 50a and 50
The displacement of the measurement point located at a position narrower than the distance between the center axes of the lenses b cannot be measured.

Further, since the laser light emitted from the optical fiber emission side end has a divergence angle of about 25 °, the laser light simultaneously emitted from the optical fibers 44a and 44b is collected by the condenser lenses 50a and 50b. Since the light is emitted and the semiconductor position detecting elements 51a and 51b have to be installed at the close positions, the light spot positions on the semiconductor position detecting elements 51a and 51b become two points. There is a problem that a large measurement error is caused by the influence of the light. Then, in order to eliminate this, the prism 49a,
When 49b is provided, there is a dilemma that the installation place becomes large and the number of prisms 49a and 49b is naturally limited. In order to solve this, a half mirror is placed on the optical axis of the semiconductor position detecting elements 51a, 51b instead of the prisms 49a, 49b.
An optical fiber 44b is applied to one of the two split lights.
In the displacement measuring device proposed above, only the position of the optical fiber 44a is determined on the side of the light-shielded semiconductor position detecting element 51b, and the light point displacement 63 on the side of the semiconductor position detecting element 51a is detected.
Measures these centers of gravity even at two focal points,
If the light intensities are equal, the optical fibers 44a and 44b
In the center of Therefore, although the exact position of the optical fiber 44b can be calculated by the calculation, the semiconductor lasers 42a and 42a
b, optical fibers 44a, 44b, semiconductor position detecting element 5
Two sets of optical measuring systems such as 1a and 51b are required, which is the same as the conventional displacement measuring apparatus described above. Further, to measure displacements of three or more points, the same measurement is performed by increasing the number of half mirrors. The arrangement of these optical components becomes very complicated, the measurement range is limited due to light shielding, and the optical measurement system requires the number of measurement points. Had a similar problem.

As described above, when it is desired to measure displacement, displacement amount or elongation at many points simultaneously, the semiconductor laser 42
The configuration of the multi-point displacement measuring apparatus by providing a large number of sets a, 42b, optical fibers 44a, 44b, semiconductor position detecting elements 51a, 51b, and the like is because the arrangement of the optical components is restricted in terms of cost. Also two optical fibers 4
If the light intensities of 4a and 44b are not equal, a measurement error occurs, which is difficult.

Further, in order to measure displacement at many points close to each other with high accuracy, it is necessary to simultaneously focus a large number of optical lasers on a large number of semiconductor position detecting elements.
Accuracy could not be expected with the conventional displacement measuring device. In addition, conventional displacement measuring devices other than those proposed by the present inventors, and any displacement measuring device such as an electric measuring device or a magnetic measuring device, have low response speed, poor accuracy, and a narrow measurement range. In addition, the displacement from a small amplitude to a large amplitude cannot be measured at various load speeds from a static load to an impact load moving at a high speed in the order of 10 μsec.

Although the number of points is described above, the number of points in this specification means that the displacement of a measurement point placed at a close distance of three or more points can be measured for the first time in practical use. It is natural that it is possible to effectively measure even a two-point displacement as in the related art with a low-cost and simple configuration. A point means two or more points. Also,
The multiple-point displacement measuring device and the multiple-point displacement measuring method described below are in a broad sense including the multiple-point displacement measuring device and the multiple-point displacement measuring method, respectively.

Therefore, in order to solve the conventional problems described above, the present invention makes it possible to simultaneously measure the displacements of a number of adjacent points at low cost and is restricted by the arrangement of the optical components for measurement. A multi-point displacement measuring device with high responsiveness, with a small measurement error even when measuring multiple points in close proximity, a wide measurement range from static loads to high-speed measuring objects in the order of 10 μs, and The purpose is to provide.

Further, the present invention makes it possible to simultaneously measure the displacement amounts of a number of close points, and to reduce the measurement error even in the measurement of a number of close points, and to perform a high-speed operation on the order of 10 μs from a static load. It is an object of the present invention to provide a multi-point displacement measuring method which has a wide measurement range up to a moving measuring object and a high responsiveness.

[0026]

In order to solve the above-mentioned problems, a multi-point displacement measuring apparatus according to the present invention comprises a plurality of optical fibers, a plurality of pulsed light sources each emitting light incident thereon, and a pulse light source. A plurality of pulsed light source drivers for oscillating each of them, a semiconductor position detecting element for detecting a photocurrent generated by light focused on a light receiving surface by a lens, and a light spot position based on the photocurrent detected by the semiconductor position detecting element. An operation amplification unit for performing an operation, at least one of an optical fiber, a condenser lens, and a semiconductor position detection element is attached to the object to be measured, and the control unit sequentially sends a drive pulse to each of the pulse light source drivers, The light source emits light cyclically.

This makes it possible to simultaneously measure the displacements of a number of adjacent points at a low cost, and there is little restriction on the arrangement of the optical components for measurement. It is possible to provide a multi-point displacement measuring device which has a small measurement error, has a wide measurement range from a static load to a measuring object moving at a high speed in the order of 10 μsec, and has high responsiveness.

Further, in the method of measuring displacement at many points according to the present invention, at least one of a plurality of optical fibers, a condenser lens, and a semiconductor position detecting element is attached to an object to be measured, and a driving pulse is sequentially transmitted to a plurality of pulse light source drivers. The pulse light source associated with each pulse light source driver is switched to emit light cyclically, the light emitted by the pulse light source enters each of the optical fibers, and the light emitted from the optical fiber is collected by the condenser lens. The method is characterized in that a light spot position is detected on a light receiving surface of a semiconductor position detecting element and displacements of a plurality of measurement points are measured.

This makes it possible to simultaneously measure the displacement amounts of a number of close points, to reduce the measurement error even in the measurement of a number of close points, and to measure at high speed from a static load on the order of 10 μs. It is possible to provide a multi-point displacement measuring method that has a wide measurement range up to the object and high responsiveness.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is directed to a plurality of optical fibers, a plurality of pulsed light sources associated with each of the optical fibers, each of which emits light incident thereon, and a pulsed light source. A plurality of pulsed light source drivers for oscillating each of the light sources, a power supply unit for supplying a driving voltage for oscillating the pulsed light source, a condenser lens for condensing light emitted from an emission side end of the optical fiber, A semiconductor position detecting element for detecting a photocurrent generated by light focused on the light receiving surface by the lens, and an operational amplifier for calculating a light spot position of each optical fiber from the photocurrent detected by the semiconductor position detecting element; A control unit for controlling the pulse light source driver, wherein at least one of an optical fiber, a condenser lens, and a semiconductor position detecting element is attached to the object to be measured; Sequentially sends drive pulses to each of the source driver, since numerous point displacement measuring device which is characterized in that light is emitted pulse light source cyclically, sequentially sends drive pulses to each of the pulse light source driver,
Since the pulsed light source emits light cyclically, there is little restriction on the arrangement of the optical components for measurement, and it is possible to simultaneously measure the displacements of a number of close points at low cost, and it is next to the semiconductor position detection element. The light from the pulsed light source does not affect the measurement, thereby reducing the measurement error even when measuring a number of points in close proximity. At least one of an optical fiber, a condenser lens, and a semiconductor position detecting element is attached to a measurement object to form a moving system in the all-optical measurement system. The displacement can be measured in relation to the fixed system. In addition, since the drive pulse is sequentially sent to each pulse light source driver and the pulse light source is switched to emit light cyclically, the measurement range is wide from static load to the measurement object that moves at high speed in the order of 10 μs, and the response is wide. A high multipoint displacement measuring device can be provided.

According to a second aspect of the present invention, in the multipoint displacement measuring apparatus according to the first aspect, the pulse light source is a semiconductor laser. Large, clear pulse waveform,
In addition, the amount of attenuation is small, and the most accurate measurement can be performed.

According to a third aspect of the present invention, the multi-point displacement according to the first or second aspect is characterized in that the condenser lens receives the light emitted from the optical fiber and focuses on the light receiving surface. Because it is a measuring device, it can receive multiple laser beams with a single lens, is less restricted by the arrangement of the optical components for measurement, and can simultaneously measure displacements of many adjacent points at low cost. Enables the laser light of the adjacent pulse light source to affect the semiconductor position detection element,
As a result, the measurement error is reduced even in the case of measuring a number of points in close proximity.

According to a fourth aspect of the present invention, the condenser lens can be exchanged according to the mounting positions of the plurality of optical fibers. Since it is a multi-point displacement measurement device, even if the measurement point is far away and the position of the emission side end attached to the measurement object is far away, it is necessary to focus on the light receiving surface with a single lens by exchanging the lens Can be.

According to a fifth aspect of the present invention, the semiconductor position detecting element has a light receiving surface large enough to receive the light emitted from the optical fiber.
4. The multi-point displacement measuring device according to any one of 4.
Driving pulses are sequentially sent to each of the pulse light source drivers, causing the pulse light source to emit light cyclically and receiving multiple lights with a single semiconductor position detection element. This makes it possible to perform measurement with a small measurement error even when measuring a large number of close points.

According to a sixth aspect of the present invention, the semiconductor position detecting element detects a two-dimensional light spot position on the light receiving surface. Since it is a point displacement measurement device, it is possible to simultaneously measure even two-dimensional measurement points at low cost, and it is possible to measure even a number of close points with a small measurement error.

According to a seventh aspect of the present invention, there is provided a sampling means for A / D-converting an output from the operational amplifying section, and the control section sequentially transmits the sampling timing of the sampling means and the pulse light source driver to the pulse light source driver. 7. Synchronizing with a drive pulse sent to
In the multi-point displacement measuring device according to any one of the above, the timing for sampling data from the analog signal output by the operational amplifier unit and the drive pulse are synchronized with each other so that the light emission timing and the sampling timing match. The data can be measured with a small measurement error without deviation of the data.

According to an eighth aspect of the present invention, there is provided the multipoint displacement measuring apparatus according to the seventh aspect, further comprising a memory for recording an output from the sampling means. The quantity can be recorded in memory.

According to a ninth aspect of the present invention, there is provided an FC type optical fiber connector which is provided between the pulse light source and the optical fiber and fixes the end of the optical fiber in a swingable manner. Since the multi-point displacement measuring device according to any one of claims 1 to 8, the arrangement of an optical fiber can be facilitated for measuring at many points.

According to a tenth aspect of the present invention, at least one of a plurality of optical fibers, a condenser lens, and a semiconductor position detecting element is attached to an object to be measured, and a driving pulse is sequentially transmitted to a plurality of pulsed light source drivers. The pulse light source associated with each pulse light source driver is switched to emit light cyclically, the light emitted by the pulse light source enters each of the optical fibers, and the light emitted from the optical fiber is collected by the condenser lens. Since the multi-point displacement measuring method is characterized in that the light spot position is detected on the light receiving surface of the semiconductor position detecting element and the displacement of a plurality of measuring points is measured, a driving pulse is sequentially transmitted to each of the pulse light source drivers. In order to make the pulse light source emit light cyclically, it is possible to simultaneously measure the displacement amounts of a number of adjacent points at a low cost, and to be adjacent to the semiconductor position detecting element. Without light pulse light source affects also the measurement error is reduced to a measurement of a number points adjacent thereto. At least one of an optical fiber, a condenser lens, and a semiconductor position detecting element is attached to a measurement object to form a moving system in the all-optical measurement system. The displacement can be measured in relation to the fixed system. In addition, since a drive pulse is sequentially transmitted to each of the pulse light source drivers to cause the pulse light source to emit light cyclically, the measurement range is wide from a static load to a measurement object that moves at high speed in the order of 10 μs, and a large number of highly responsive devices are provided. A point displacement measuring device can be provided.

According to an eleventh aspect of the present invention, the pulse light source is a semiconductor laser.
0, the semiconductor laser as a pulse light source has a large optical output, a clear pulse waveform, and a small amount of attenuation, so that the most accurate measurement is possible. (Embodiment 1) Hereinafter, a multipoint displacement measuring apparatus according to Embodiment 1 of the present invention will be described. FIG. 1 is a configuration diagram of a multipoint displacement measuring device according to Embodiment 1 of the present invention,
FIG. 2 is an explanatory view of measuring a light spot position by a semiconductor position detecting element of the multiple-point displacement measuring device according to the first embodiment of the present invention;
FIG. 3 is an output waveform diagram of the semiconductor laser of the multi-point displacement measuring device according to the first embodiment of the present invention, and FIG. 4 is a displacement amount diagram measured by the multi-point displacement measuring device according to the first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a semiconductor laser driver,
, 1n are semiconductor laser drivers (pulse light source of the present invention) constituting the semiconductor laser driving unit 1, 2
, 2n are semiconductor lasers (the pulse light source of the present invention). The semiconductor lasers 2a, 2b,..., 2n output light having a wavelength in the visible region of 690 nm or less in consideration of eyes. A light output of about 10 mW to 50 mW is desirable. In the first embodiment, the semiconductor lasers 2a, 2b,.
Light emitting diodes and other light emitting elements may be used. However,
Semiconductor lasers 2a, 2b,..., 2n as pulse light sources
The use of a light source has a large optical output, a clear pulse waveform, and a small amount of attenuation, so that the most accurate measurement is possible.

.., 3n are the semiconductor lasers 2a, 3b,.
The microlenses 4a, 4b,..., 4n for condensing the light emitted from a, 2b,..., 2n are flexible and lightweight for transmitting the light condensed by the microlenses 3a, 3b,. , 5n are FC-type optical fiber connectors in which the end faces of the optical fibers 4a, 4b,..., 4n are securely disposed near the focal points of the microlenses 3a, 3b,. It is. Optical fiber 4a,
4b,..., 4n have a core diameter of 30 to 100 μm and an outer diameter of 10
Those having a thickness of about 0 to 500 μm are suitable. And FC
The optical fiber connectors 5a, 5b,..., 5n must securely fix the light source side end faces of the optical fibers 4a, 4b,.
, 4n can be quickly and easily attached and detached. Thereby, the optical fiber 4
, 4n can be adjusted by taking the optical fibers 4a, 4b,..., 4n in and out. Further, when the ratio of incident light decreases due to deterioration of the end face, it can be dealt with by polishing the end face.

6 is an object to be measured such as a tensile test material, 7a,
7b are optical fibers 4 with respect to the object 6 to be measured.
a, 4b,..., 4n are attachment members such as adhesive tapes for fixing the emission-side ends. The mounting members 7a, 7
, 7n are optical fibers 4a, 4b,.
Is fixed with care so that the emitted light is directed in a predetermined direction suitable for measurement. Reference numeral 8 denotes the semiconductor lasers 2a, 2b,.
A power supply unit for supplying a drive current for oscillating n.

Reference numeral 9 denotes optical fibers 4a, 4b,.
A condenser lens 10 for receiving the light emitted from the light source and condensing and focusing each light at a position where the light is emitted is a two-dimensional semiconductor position detecting element. The position of the focused light spot can be measured by the magnitude of the photocurrent. However, the output is converted into a voltage and output. The condenser lens 9 includes optical fibers 4a, 4b,.
・ To receive a plurality of laser beams emitted from 4n and focus on the light receiving surface, so that a single lens can receive a plurality of laser beams and to dispose optical components such as a prism as in the conventional case. There is no restriction. Therefore, it is not necessary to increase the distance between measurable measurement points, and it is possible to simultaneously measure the displacement amounts of a number of close points at low cost. The condensing lens 9 increases or decreases the distance between the emission-side ends of the plurality of optical fibers 4a, 4b,..., 4n attached to the measurement object 6 by the attachment members 7a, 7b,. If it does, it can be replaced according to the change in the mounting position. Therefore,
Even if the distance between the emission-side ends is widened, it is possible to focus on the light receiving surface with a single condenser lens by exchanging the condenser lens 9, thereby maintaining the compactness of the measuring apparatus and measuring points. Can be responded to. The position and type of the condensing lens are based on Gauss's lens formula 1 / s ₁
+ 1 / s ₂ = 1 / f (f is the focal length, and s ₁ and s ₂ refer to FIG. 1), so that the distances s ₁ and s
_The lens may be replaced by managing the measurement range with the ratio of ₂ .

It should be noted that the condensing lens 9 is composed of _two lenses (focal lengths f ₁ and f ₂ ) and is arranged at a distance d between the lenses, so that 1 / f = 1 / f ₁ +1. / _{f 2}
From the relationship of −d / f ₁ f ₂ , it is possible to equivalently reduce the focal length f. In this case, the focal length f can be easily changed, and high-resolution measurement can be performed.

In the first embodiment, all the optical members 4a, 4b,..., 4n are fixed to the object 6 to be measured by mounting members 7a, 7b,. Although the moving system in the system is configured, this is not limited to the system in which the emission ends of the optical fibers 4a, 4b,..., 4n are fixed. Optical fibers 4a, 4b,.
At least one of each of the 4n emission-side ends, the condenser lens 9, and the semiconductor position detecting element 10 is attached to a measurement object to form a moving system, and displacement can be measured in relation to a fixed system. For example, when the semiconductor position detecting element 10 is attached to the measuring object 6, the optical fibers 4a, 4b,.
This is a displacement measuring device in which the light emitting side of 4n or the like is configured as a fixed system.

Reference numeral 11 denotes a microprocessor or the like.
A control unit 12 for controlling the displacement measuring device inputs an output from the semiconductor position detecting element 10, calculates a coordinate position (displacement) of each light spot position, and calculates a displacement amount from a difference between each point. An operational amplifier that can also calculate, 13 is a sampling means for sampling the analog signal from the operational amplifier 12, and 14 is an A / D
A memory unit for recording the converted data;
And clock means for generating an external clock to be supplied to the sampling means 13. The control unit 11 adjusts the timing of the sampling by the sampling unit 13 and the timing of the drive pulse for operating the semiconductor laser drivers 1a, 1b,..., 1n based on the external clock supplied from the clock unit 15. Reference numeral 16 denotes a display unit such as a display, which displays an output obtained by the sampling unit 13 or an analog voltage output on a screen in some cases.

The measurement principle of the multi-point displacement measuring device according to the first embodiment of the present invention described above will be described with reference to FIGS.
A description will be given based on FIGS. In FIG. 2, reference numeral 17 denotes a semiconductor position detecting element 10 which causes photoelectric conversion when receiving light.
The light receiving surfaces 18a and 18b output light currents I _x1 and I _x2 when receiving light, respectively.
c and 18d receive photocurrents _Iy1 and _Iy1 , respectively.
An output terminal on the y-axis side for outputting _y2 , 19 is an optical fiber 4
, 4n are focused on the light receiving surface 17 by the condenser lens 9 at the light spot position, and 20a is on the light receiving surface 17 on the y-axis side equidistant from the output terminals 18c, 18d. Intermediate position, 20b is the output terminal 18a, 1 on the light receiving surface 17.
8b is an intermediate position on the x-axis side equidistant from 8b. The semiconductor position detecting element 10 of the first embodiment can measure the displacement of the measurement point in two dimensions.

That is, the intermediate position 20b and each output terminal 1
8a, the distance to 18b are each _{L x,} the distance to the intermediate position 20b and the point position 19 is x. When the light spot position 19 is at the intermediate position 20b, x = 0,
Output terminals 18a, no difference in photocurrent _{I x1, I x2} from 18b. Similarly, the intermediate position 20a and each output terminal 1
8c, the distance to 18d are each _{L y,} the distance to an intermediate position 20a and the light spot position 19 is y. When the light spot position 19 is at the intermediate position 20a, y = 0,
Output terminals 18c, no difference in photocurrent _{I y1, I y2} from 18d. Generally, the photocurrents _Ix1 and _Ix2 are detected at the output terminals 18a and 18b, and the output terminals 18c and 18d are detected.
When the photocurrents I _y1 and I _y2 are detected at
(X, y) is represented by (Equation 2).

[0050]

(Equation 2) When this operation is performed by the operation amplifier 12, the mounting member 7
7n, it is possible to measure where the output ends of the optical fibers 4a, 4b,..., 4n attached to the measurement object 6 are present.

In the first embodiment, the displacement of the two-dimensional measurement point is measured by (Equation 2) as described above. However, as described in the description of the conventional displacement measuring device,
One-dimensional measurement may be performed. In this case, the displacement is calculated according to (Equation 1) instead of (Equation 2).

The multipoint displacement measuring device according to the first embodiment uses the semiconductor lasers 2a and 2a to measure the displacement.
Unless the oscillations of 2b,..., 2n are operated so as not to overlap, measurement becomes impossible. Therefore, the control unit 11 sequentially and cyclically sends the drive pulses shifted by at least the pulse width to the semiconductor laser drivers 1a, 1b,..., 1n, and changes the drive voltage from the power supply unit 8 to the semiconductor lasers 2a and 2n.
, 2n are switched and supplied and oscillated. Thus, the semiconductor lasers 2a, 2b,..., 2n are sequentially focused on the semiconductor position detecting element 10 while being cyclically switched in time units of the pulse width, and are calculated and output by the operational amplifier 12, respectively. You.

FIG. 3 shows semiconductor lasers 2a, 2b,.
FIG. 3 is an output waveform diagram of n. In FIG. 3, reference numeral 21 denotes an external clock supplied by the clock means 15;
It is generated based on the external clock supplied from the clock means 15, and is controlled by the controller 11 from the semiconductor laser drivers 1 a, 1 b,
.. Is a driving pulse supplied to 1n. For example, the external clock 21 of the first embodiment is
a, 2b,..., 2n may be constituted by a pulse having one cycle having the same time width as the operating pulse width, and this pulse is directly input to the sampling means 13 as a sampling clock, and a semiconductor laser It is sufficient to input the signals to the drivers 1a, 1b,. Semiconductor laser drivers 1a, 1b, ..., 1n
Are driven by the driving pulses so that the semiconductor lasers 2a, 2b,.
, 2n is switched to oscillate and a visible laser beam is output. This light is detected by the semiconductor position detecting element 10, operated by the operational amplifier 12, and recorded in the memory 14.

Thus, the optical fibers 4a, 4b,.
., Light from 4n is emitted with a time shift so as not to overlap, so that a certain optical fiber
For example, light exits from the optical fiber 4a and does not exit from other optical fibers. In the next time zone, light is emitted only from another optical fiber 4b. Thus, the light spot position 19 on the semiconductor position detecting element 10 described above does not become two points. Therefore, the output of the semiconductor position detecting element 10 has a fixed pulse width (time interval) and the optical fibers 4a, 4b,.
., 4n can be sequentially switched, output in the form of a voltage, and detected. If this “pulse width × number” has a sufficient margin for the speed of the phenomenon and is small, the same optical fibers 4a, 4a, which are stored in the A / D conversion by the sampling means 13 in time.
By connecting the output voltages of 4b,..., 4n, an entire displacement line can be obtained, and displacement measurement at many points can be realized. The displacement and elongation are measured between the optical fibers 4a, 4b,..., 4n.

In FIG. 4, reference numeral 31 denotes a semiconductor laser 2a.
Is a displacement line of the light spot position of the semiconductor laser 2a in which the light spot position of the semiconductor laser 2a is plotted with respect to time, and 32 is a displacement line of the semiconductor laser 2b in which the change of the light spot position of the semiconductor laser 2b is plotted with respect to time. It is a displacement line of a light spot position. However, the displacement line in FIG. 4 is shown after being converted into a calibrated actual displacement amount. Similarly, reference numeral 33 denotes a displacement line of the light spot position of the semiconductor laser 2n in which the change of the light spot position of the semiconductor laser 2n is plotted with respect to time. It can be seen that both changes linearly. In FIG. 4, displacement lines 31 to
The respective differences on the x-axis of 33 are the semiconductor lasers 2a and 2
b, · ·, the semiconductor laser 2 when corresponding to the distance in the x-axis direction of the exit-side end position of the 2n, which consisted time t ₁ to time t ₂
It can be seen that the amount of displacement occurs because the distance between the emission-side ends of a, 2b,..., 2n decreases. Although not shown, when the displacement line in the y-axis direction is measured in exactly the same way,
Each displacement line changes linearly. The differences between the displacement lines on the y-axis are the semiconductor lasers 2a, 2b,.
Is the distance in the y-axis direction of the emission side end of These are measured and recorded in the memory unit 14. As described above, the displacement lines are obtained by connecting the output voltages that are stored at intervals in time by the data conversion by the sampling means 13, the displacement measurement of many points can be realized, and the displacement amount and elongation are measured. Will be.

Next, the operation of the multi-point displacement measuring apparatus according to the first embodiment will be described. When the measurement is performed, the optical fibers 4a, 4b,..., 4n are adhered to the object 6 whose displacement is to be measured at an interval of 1 mm or less to several tens mm. When inputting laser light to the optical fibers 4a, 4b,..., 4n, the optical fibers 4a, 4b,.
., Pulse oscillation of the same number of semiconductor lasers as the semiconductor lasers 2a, 2n
b, ..., 2n are oscillated. For example, the laser light emitted from the laser 2a is incident on the optical fiber 4a by using the FC type optical fiber connector 5a, and is different from the conventional one from the emission end which is the other end of the optical fiber 4a. Instead of continuous light, pulsed laser light is emitted.
Similarly, pulsed light is emitted from the optical fibers 4b,..., 4n.
The passage times of the laser beams b,..., 4n are sequentially shifted without overlapping. An operation speed of MHz is also possible. The laser light emitted from the optical fibers 4a, 4b,..., 4n (the laser light is emitted from only one fiber when focusing on an arbitrary time) is condensed through a single condenser lens 9, One focal point is formed on the light receiving surface of the single semiconductor position detecting element 10 placed at the position where the light flux becomes minimum.

The movement of the light spot position 19 is caused by the movement of the optical fibers 4a and 4a.
b,..., 4n
The semiconductor position detecting element 10 first outputs the optical current corresponding to the position where the optical fiber 4a is attached and the optical fiber 4b,..., 4n at the next time, and repeats this operation cyclically. The output of the semiconductor position detecting element 10 when the laser light shifts is, for example, an optical fiber 4a.
From the position, the voltage suddenly becomes the position indicating the position of the optical fiber 4b, so that it becomes discontinuous. The photocurrent output received by the semiconductor position detecting element 10 is converted into a voltage, amplified by the operational amplifier 12, A / D converted by the sampling means 13, and stored in the memory 14. At this time, it should be noted that the control unit 11 outputs a driving pulse synchronized with the sampling clock of the sampling unit 13 and the semiconductor laser 2
a, 2b,..., 2n need to be oscillated. Similar measures may be taken. As described above, in the first embodiment, the external clock 21 from the clock means 15 is constituted by a pulse whose period is exactly the same as the operating pulse width of the semiconductor lasers 2a, 2b,. This is directly input to the sampling means 13 as a sampling clock, and is input to the semiconductor laser drivers 1a, 1b,..., 1n as drive pulses to achieve synchronization.

The displacement data obtained in this manner is one optical fiber 4a (or 4b,..., 4n, etc.).
If attention is paid to this, it is intermittent data that is temporally interrupted. However, if the speed of the phenomenon is about the same as or slower than the pulse interval of the semiconductor laser 2a (or 2b,..., 2n), the pulse width (n-1)
The missing points can be complemented by connecting the missing points with straight lines. That is, if attention is paid to another time step in one cycle of the pulse width, displacements at other points can be obtained in the same manner, and displacements at n points can be measured at once. However, when the speed of the phenomenon is high, it is difficult to reproduce this because there are high frequency vibrations even if (n-1) complementation is performed by straight lines on the displacement lines 31 to 33,
According to the measurement method of the present invention, when complementing the missing displacement data of the displacement line 32, one pulse before and after the displacement data of the displacement line where the measurement data exists and the displacement data of the displacement line 32 closest to this time, By calculating using six displacement data for convenience, the vibration of high frequency is left,
The value of the displacement data of the displacement line 32 can be complemented.
Thus, the high frequency included in the waveform is not overlooked, and the existence and frequency of the high frequency can be known. That is, it is possible to make up for the drawback caused by the coarse sampling time.

Note that, instead of fixing the optical fibers 4a, 4b,..., 4n to the object to be measured as in the first embodiment, the lens 9 or the semiconductor position detecting element 10 is attached to the object to be measured. It is also possible to measure displacement,
The most suitable installation form can be selected, and it is possible to provide an optimal multi-point displacement measuring device suitable for the application.

As described above, the multi-point displacement measuring apparatus according to the first embodiment of the present invention can be used even if the number of measuring points increases.
The semiconductor position detecting element 10 and the operational amplifying unit 12 may be single each differently from the conventional one, and the more the measuring points, the better the cost performance. In addition, as described above, the multiple-point displacement measuring device has a good frequency response, and can measure displacement from a small amplitude to a large amplitude under various load speeds.
It is possible to measure displacement, displacement amount, and elongation between narrow multiple points and multiple points. Therefore, the present measuring apparatus can be applied to low-speed, multi-point displacement measurement, and can be expected to be used in various fields irrespective of the displacement measurement range and the deformation speed. For example, it is difficult to measure at once a complex movement amount and vibration of a large number of dense points that are expected to be miniaturized in the future with the conventional apparatus, but according to the multipoint displacement measuring apparatus of the present invention, Becomes possible. For example, it is possible to measure the amount of eccentricity of a rotating body, the amount of displacement of multiple heads of an inkjet printer, and the amount of movement of a robot joint. Also, since it has a high frequency response, it is very suitable for measuring the displacement of phenomena of several kHz to several tens of kHz such as impact. As an example of such an application, the present invention can be applied to simultaneous velocity measurement of a collision object, seismic analysis or control of buildings and structures, and analysis of shaking and vibration of a hull. Also, compared to strain gauges, this multi-point displacement measuring device does not measure the strain of the mounting member itself even when pasted, and up to a large strain range exceeding the measurement limit of the strain gauge. The displacement amount can be measured, and since the measurement is performed substantially in a non-contact manner, there is almost no possibility of noise being introduced, and the device has high reliability.

[0061]

The multipoint displacement measuring apparatus according to the first aspect of the present invention includes an optical fiber, a plurality of pulsed light sources, and a semiconductor position detecting element. At least one of the semiconductor position detecting elements is attached to the object to be measured, and the control unit sequentially sends a driving pulse to each of the pulsed light source drivers to cause the pulsed light source to emit light cyclically. Since the drive pulse is sent and the pulse light source emits light cyclically, the arrangement of the optical components for measurement is less restricted, and it is possible to simultaneously measure the displacements of many nearby points at low cost, and semiconductor Light from the adjacent pulse light source does not affect the position detection element, thereby reducing measurement errors even when measuring many points in close proximity. . At least one of an optical fiber, a condenser lens, and a semiconductor position detecting element is attached to a measurement object to form a moving system in the all-optical measurement system. The displacement can be measured in relation to the fixed system. In addition, since the drive pulse is sequentially sent to each pulse light source driver and the pulse light source is switched to emit light cyclically, the measurement range is wide from static load to the measurement object that moves at high speed in the order of 10 μs, and the response is wide. A high multipoint displacement measuring device can be provided.

In the multipoint displacement measuring apparatus according to the second aspect of the present invention, since the pulse light source is a semiconductor laser, the semiconductor laser as the pulse light source has a large light output, a clear pulse waveform, and a small attenuation. , The most accurate measurement is possible.

In the multi-point displacement measuring device according to the third aspect of the present invention, since the condenser lens receives the laser beam emitted from the optical fiber and focuses on the light receiving surface, a plurality of displacements can be obtained by a single condenser lens. Light, and there are few restrictions on the arrangement of the optical components for measurement.It is also possible to simultaneously measure the displacements of a number of adjacent points at low cost, and the pulse light source adjacent to the semiconductor position detection element can be measured. Light has no effect,
As a result, the measurement error is reduced even in the case of measuring a number of points in close proximity.

In the multi-point displacement measuring device according to the fourth aspect of the present invention, the condenser lens is exchanged according to the mounting position of the plurality of optical fibers. Even if the end position becomes far away, it is possible to focus on the light receiving surface with a single condenser lens by exchanging the condenser lens.

In the multi-point displacement measuring device according to the fifth aspect of the present invention, since the semiconductor position detecting element is provided with a light receiving surface large enough to receive the light emitted from the optical fiber, it is sequentially provided to each of the pulse light source drivers. A drive pulse is sent, the pulse light source emits light cyclically, and multiple light is received by a single semiconductor position detection element, so it is possible to simultaneously measure the displacement of many adjacent points at low cost, Even a measurement at many points in close proximity can be measured with a small measurement error.

In the multi-point displacement measuring device according to the sixth aspect of the present invention, since the semiconductor position detecting element detects the two-dimensional light spot position on the light receiving surface, even if the two-dimensional measurement point is low. Measurement can be performed simultaneously at a low cost, and measurement can be performed with a small measurement error even when measuring a large number of close points.

In the multi-point displacement measuring device according to the seventh aspect of the present invention, the control unit synchronizes the sampling timing of the sampling means with the drive pulse sequentially and cyclically sent to the pulse light source driver, so that the operational amplifier unit outputs By synchronizing the timing of sampling data from the analog signal with the driving pulse, the light emission timing of light and the sampling timing match, and data can be measured without deviation and with a small measurement error.

Since the multipoint displacement measuring device according to the eighth aspect of the present invention includes the memory unit for recording the output from the sampling means, the displacement and the displacement amount can be recorded in the memory.

The multipoint displacement measuring device according to the ninth aspect of the present invention includes the FC type optical fiber connector for fixing the end of the optical fiber so as to swing freely. The arrangement can be facilitated.

According to a tenth aspect of the present invention, there is provided a multi-point displacement measuring method, wherein at least one of each of the emission side ends of a plurality of optical fibers, a condenser lens, and a semiconductor position detecting element is attached to an object to be measured. To emit light cyclically, the light emitted by the pulsed light source is incident on each of the optical fibers, and the light emitted from the optical fiber is condensed by a condenser lens, and the light spot position on the light receiving surface of the semiconductor position detecting element To detect the displacement of a plurality of measurement points, sequentially send a drive pulse to each of the pulse light source drivers, and sequentially send a drive pulse to each of the pulse light source drivers to cause the pulse light source to emit light cyclically. Since the light source emits light cyclically, it is possible to simultaneously measure the displacements of a number of adjacent points at low cost, and a pulse is placed next to the semiconductor position detection element. Without the light source of the light will affect the measurement error is reduced even measurement of multiple points in close proximity thereto. At least one of an optical fiber, a condenser lens, and a semiconductor position detecting element is attached to a measurement object to form a moving system in the all-optical measurement system. The displacement can be measured in relation to the fixed system. In addition, since a drive pulse is sequentially transmitted to each of the pulse light source drivers to cause the pulse light source to emit light cyclically, the measurement range is wide from a static load to a measurement object that moves at high speed in the order of 10 μs, and a large number of highly responsive devices are provided. A point displacement measuring device can be provided.

According to the multipoint displacement measuring method of the present invention, since the pulse light source is a semiconductor laser, the semiconductor laser as the pulse light source has a large light output, a clear pulse waveform, and a small amount of attenuation. , The most accurate measurement is possible.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a multipoint displacement measuring device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of measurement of a light spot position by a semiconductor position detecting element of the multiple-point displacement measuring device according to the first embodiment of the present invention.

FIG. 3 is an output waveform diagram of a semiconductor laser of the multiple-point displacement measuring device according to the first embodiment of the present invention.

FIG. 4 is a displacement diagram measured by a multipoint displacement measuring device according to the first embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional displacement measuring device.

FIG. 6 is an explanatory diagram of measuring a light spot position by a semiconductor position detecting element of a conventional displacement measuring device.

FIG. 7 is a displacement diagram measured by a conventional displacement measuring device.

[Explanation of symbols]

 1 semiconductor laser driver 1a, 1b, ..., 1n semiconductor laser driver 2a, 2b, ..., 2n semiconductor laser 3a, 3b, ..., 3n micro lens 4a, 4b, ..., 4n optical fiber 5a, 5b, .., 5n FC-type optical fiber connector 6 Measurement object 7a, 7b,. Means 16 Display unit 17 Light receiving surface 18a, 18b, 18c, 18d Output terminal 19 Light spot position 20a, 20b Intermediate position 21 External clock 22, 23, 24 Drive pulse 31, 32, 33 Displacement line 41 Power supply on / off unit 41a, 41b Power switches 42a, 42b Semiconductor lasers 43a, 43b Microlenses 44a, 44b Optical fiber 45a, 45b FC-type optical fiber connector 46 Object to be measured 47a, 47b Mounting member 48 Power supply unit 49a, 49b Prism 50a, 50b Condensing lens 51a, 51b Semiconductor position detecting element 52 Control unit 53 Operational amplification unit 54 Sampling unit 55 Memory unit 56 Clock unit 57 Display unit 61 Light receiving surface 62a, 62b Output terminal 63 Light spot position 64 Intermediate position 67, 68 Displacement line

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kiyoshi Takahashi 2-3-11 Nagaoka, Minami-ku, Fukuoka City, Fukuoka Prefecture (72) Philippe Vegulin, Chemin des Forgresses No. 4 in Lausanne, Vaud, Switzerland, Switzerland 72) Inventor Kazuo Shinkawa 6-3-5 Takao, Dazaifu City, Fukuoka Prefecture F-term (reference) AA01 EA02 EB07

Claims (11)

[Claims] A plurality of optical fibers, a plurality of pulsed light sources associated with each of the optical fibers and emitting light incident thereon, a plurality of pulsed light source drivers for oscillating each of the pulsed light sources, A power supply unit for supplying a drive voltage for oscillating the pulse light source, a condenser lens for condensing light emitted from the exit side end of the optical fiber, and a focal point formed on a light receiving surface by the condenser lens A semiconductor position detection element for detecting a photocurrent generated by light; an operation amplification unit for calculating a light spot position of each optical fiber from the photocurrent detected by the semiconductor position detection element; and a control unit for controlling the pulse light source driver And at least one of the optical fiber, the condenser lens, and the semiconductor position detection element is attached to the measurement target, and the control unit includes: Serial pulse light source sends a sequential driving pulses to each of the driver, multiple point displacement measuring device which is characterized in that by emitting the pulsed light source cyclically. 2. The multipoint displacement measuring device according to claim 1, wherein said pulse light source is a semiconductor laser. 3. The multi-point displacement measuring apparatus according to claim 1, wherein the condenser lens receives light emitted from the optical fiber and focuses the light on the light receiving surface. 4. The multipoint displacement measuring apparatus according to claim 1, wherein said condenser lens can be exchanged according to a mounting position of a plurality of optical fibers. 5. The multipoint displacement measurement according to claim 1, wherein the semiconductor position detecting element has a light receiving surface large enough to receive light emitted from the optical fiber. apparatus. 6. A semiconductor device according to claim 1, wherein said semiconductor position detecting element detects a two-dimensional light spot position on a light receiving surface.
5. The multiple-point displacement measuring device according to any one of items 1 to 4. 7. A sampling unit for A / D-converting an output from said operational amplifier, wherein said control unit synchronizes a sampling timing of said sampling unit with a driving pulse sequentially and cyclically sent to said pulse light source driver. The multiple-point displacement measuring device according to any one of claims 1 to 6, wherein: 8. The multipoint displacement measuring apparatus according to claim 7, further comprising a memory unit for recording an output from said sampling means. 9. An F provided between the pulse light source and the optical fiber to fix an end of the optical fiber in a swingable manner.
The multi-point displacement measuring device according to any one of claims 1 to 8, further comprising a C-type optical fiber connector. 10. At least one of a plurality of optical fibers, a condensing lens, and a semiconductor position detecting element is attached to an object to be measured, and a driving pulse is sequentially sent to a plurality of pulse light source drivers to be associated with each pulse light source driver. A pulse light source is switched to emit light cyclically, light emitted by the pulse light source is incident on each of the optical fibers, light emitted from the optical fiber is condensed by a condenser lens, and light is received by a semiconductor position detecting element. A multi-point displacement measuring method, comprising detecting a light spot position on a surface and measuring displacements of a plurality of measurement points. 11. The method according to claim 10, wherein said pulse light source is a semiconductor laser.