JP2003148931A - Method and device for measuring inside diameter of hollow transparent body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for measuring inside diameter of hollow transparent body capable of measuring the inside irregularities or curve of a glass bead. SOLUTION: This method for measuring the inside shape of a glass bead a that is a hollow transparent body comprises putting a plug to the opening part of the glass bead a to seal the cavity in the glass bead a; dipping the sealed glass bead a in a liquid 1 having the same refractive index as that of the glass bead a; irradiating the glass bead a with laser beam in this state; receiving the transmitted light by a optical sensor 44 divided in two; and detecting the inside ridge of the glass bead a from the light receiving quantity of each optical sensor 44a and 44b. The glass bead a is scanned in the axial direction (the vertical direction to the surface of Fig. 1) to measure the inside irregularities or curve of the through-hole b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring the inner diameter of a hollow transparent body, and more specifically, to the inner diameter of a hollow transparent body such as glass beads used for connecting optical fibers to prevent bending or unevenness. Regarding measurement technology.

[0002]

2. Description of the Related Art An optical fiber has been conventionally known as an optical waveguide for optical communication. As is well known, this optical fiber is formed by forming a clad having a thickness of about 0.1 mm on the outside of a quartz core having a diameter of about 50 μm and coating the outside with urethane or nylon. Glass beads a having a shape as shown in FIG. 4 are used for connecting the optical fibers.

This glass bead a is a glass part having a length of about 2 mm, and its inner diameter is 0.1 mm in the axial direction.
A through hole b of a certain degree is formed. When connecting the optical fibers, the outer circumference of the optical fibers is sprinkled with ultraviolet curable resin, which is attached to both ends of the glass beads a, and ultraviolet rays are externally applied to cure the ultraviolet curable resin to connect the optical fibers. Has been done.

[0004]

By the way, in such a glass bead, its inner diameter (the inner peripheral surface of the through hole)
Although it is desirable that the shape of the glass beads be formed straight in the axial direction without unevenness, conventionally, no method has been provided for measuring the shape of the inner diameter of such glass beads.

That is, since the inner diameter of the glass beads is extremely small, about 0.1 mm, as described above, the inner diameter is photographed by an image pickup means such as a CCD camera and the irregularity or bending of the inner diameter is detected from the photographed image. Was difficult.

The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide a method for measuring the inner diameter of a hollow transparent body capable of measuring unevenness and bending of the inner diameter of glass beads, and a method therefor. To provide a device.

[0007]

In order to achieve the above object, the method for measuring the inner diameter of a hollow transparent body of the present invention is a method for measuring the shape of the inner diameter of an object to be measured, which is made of a hollow transparent body. The opening of the object is plugged to seal the cavity inside the object to be measured, and the sealed object to be measured is immersed in a liquid having the same refractive index as the object to be measured, and light is applied to the object to be measured in this state. It is characterized by irradiating and detecting the shape of the inner diameter of the measured object by an optical method.

That is, in the present invention, when measuring the shape of the inner diameter of the object to be measured, the cavity of the object to be measured is immersed in a liquid having the same refractive index as that of the object to be measured while the cavity of the object to be measured is sealed. Since the object to be measured and the liquid have the same refractive index, when this state is optically captured, it is equivalent to the cavity of the object to be measured floating in the liquid. The present invention detects the shape of the inner diameter of the cavity of the object to be measured by detecting this state by an optical method.

As a preferred embodiment of the present invention, the opening of the object to be measured is plugged to seal the cavity in the object to be measured, and the sealed object to be measured is refracted in the same manner as the object to be measured. The sample is dipped in a liquid of a certain ratio, and in this state, the object to be measured is irradiated with light, the transmitted light is received, and the shape of the inner diameter of the object to be measured is detected from its strength.

As another preferred embodiment, the opening in the measured object is plugged to seal the cavity in the measured object, and the sealed measured object has the same refractive index as that of the measured object. By immersing it in a liquid and irradiating the measured object with light in this state, the irradiated light receives reflected light reflected by the ridge line of the cavity of the measured object (that is, the inner peripheral surface of the measured object). Detect the shape of the inner diameter of the measured object from its strength

That is, according to the present invention, the object to be measured is immersed in a liquid having the same refractive index as that of the object to be measured, the cavity of the object to be measured is optically raised, and light is transmitted therethrough to obtain a transmission. Bending and unevenness of the inner diameter of the object to be measured are measured based on the intensity of light and reflected light.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings.

Embodiment 1 FIG. 1 is a front view showing an example of a schematic structure of a hollow transparent body inner diameter measuring apparatus according to the present invention, and FIG. 2 is a side view thereof.

Specifically, this device measures the inner diameter shape of glass beads (measurement object) a of a hollow transparent body as shown in FIG. Light means 3, light receiving means 4, detecting means 5, and driving means 6
And a control means 7 as a main part.

The liquid 1 is a glass bead a as described later.
The liquid for dipping the liquid is a liquid having the same refractive index as the glass beads a. That is, as the liquid 1, a liquid having the same refractive index as glass as the material of the glass beads a is used.

The container 2 is a container for accommodating the liquid 1, and has an opening area and a depth dimension capable of immersing the entire glass beads a in the liquid 1. The container 2 is made of a material (glass) having the same refractive index as the glass beads a.

The light projecting means 3 is for irradiating the glass beads a immersed in the liquid 1 with light having a uniform intensity distribution in the radial direction (the arrow x direction in the drawing), It includes a light source 31, a concave lens 32 and a plano-convex lens 33.

The light source 31 is a light emitting source that outputs a laser beam such as an argon ion laser. The laser beam output from the light source 31 is diffused by the concave lens 32 and the plano-convex lens 33 as shown in the figure. The glass beads a are irradiated with the light by refracting in the y direction (see the arrow y in the figure). That is, the glass beads a are irradiated with the laser light in the state of parallel light fluxes directed in the y direction.

The light receiving means 4 is provided so as to face the light projecting means 3 with the glass beads a sandwiched therebetween, and receives the light transmitted through the glass beads a and photoelectrically converts it. The case 42 provided with the hole 41, the convex lens 43, and the two-divided optical sensor 44 are mainly configured.

The case 42 is a container for accommodating the convex lens 43 and the two-division optical sensor 44, and a pinhole 41 is formed in the bottom portion 42a provided facing the glass beads a as shown in the figure. ing. The pinhole 41 is sealed with a glass bead a or a transparent member (for example, a glass member) 45 having the same refractive index as that of the liquid 1, and the tip of the case 42 is placed in the liquid 1 as illustrated. Even if it is soaked, it is waterproofed so that the liquid 1 does not enter the case 42.

As is well known, the two-divided photosensor 44 is composed of a pair of photosensors 44a and 44b arranged in parallel at a predetermined interval, and each photosensor 44a and 44b receives the quantity of light received ( An electric signal is output (photoelectric conversion) according to the intensity of light.

The two-divided optical sensor 44 is arranged such that the optical sensors 44a and 44b are arranged side by side in the radial direction of the glass beads a (direction of arrow x in the figure) as shown in the figure. There is. Further, the center of the pinhole 41 and the center of the convex lens 43 are arranged concentrically, and the optical sensors 44a, 4 are sandwiched by a line connecting these centers.
4b are arranged symmetrically.

That is, in the present embodiment, the laser light entering the case 42 through the pinhole 41 is magnified by the convex lens 43 and each optical sensor 4 of the two-division optical sensor 44.
4a and 44b are configured to receive light.

The detecting means 5 is an arithmetic unit for detecting the shape of the cavity (inner diameter) of the glass beads a from the output of the light receiving means output from the two-division optical sensor 44. From the electric signals output from the optical sensors 44a and 44b (signals converted into digital signals through an A / D conversion circuit (not shown)), the respective optical sensors 44a and 44b
Detects the amount of light received by the optical sensor 44a, 44
Calculations such as comparing the amounts of light received at b are performed.

The driving means 6 is an actuator for moving the light projecting means 3 and the light receiving means 4 in a predetermined scanning direction in synchronization, and the operation of the actuator can be controlled by the control means 7. .

Specifically, in this actuator, the light emitting means 3 and the light receiving means 4 can scan the entire glass beads a in the radial direction (x direction) and the axial direction (x direction) of the glass beads a. Each of them is movable in the z direction).

The control means 7 is composed of a microcomputer provided with a control program for controlling the operation of each part of the apparatus. Specifically, the operation control of the drive means 6 and the turning on / off of the light source 31 are controlled. Further, the execution control of various processes such as the calculation process in the detecting means 5 is performed.

Now, the shape measurement of the inner diameter of the glass beads a using the inner diameter measuring device of the hollow transparent body configured as described above will be described.

In the measurement, first, the through holes b are formed in the openings at both ends of the through holes b provided in the glass bead a to be measured.
The sealing plugs 8 and 8 for sealing are attached (see FIG. 2) to seal the cavity formed in the glass beads a. The example shown in FIG. 2 shows the case where the sealing plug 8 is inserted into the inner diameter of the opening of the glass bead a in a close contact manner, but the sealing plug 8 seals the through hole b of the glass bead a. If so, it may be a seal removably attached to the end surface of the opening, and the specific shape thereof can be appropriately changed in design.

When the through hole b of the glass bead a is sealed, then the sealed glass bead a is immersed in the liquid 1 filled in the container 2, and in this state, the light source 31 is turned on and the glass bead is turned on. A is irradiated with laser light, and the transmitted light is received by the two-division optical sensor 44. In parallel with this, the driving means 6 is driven to move the light projecting means 3 and the light receiving means 4 in a predetermined scanning direction (specifically, the x direction and the z direction) to start scanning.

Here, the laser light output from the light source 31 when the light source 31 is turned on has a concave lens 3 as shown in FIG.
The glass beads a are irradiated as a parallel light flux which is diffused by 2 and refracted by the plano-convex lens 33 and headed in the y direction (see the arrow y in the figure).

On the other hand, since the container 2 and the liquid 1 filled in the container 2 have the same refractive index as that of the glass beads a as described above, the liquid 1 and the body of the glass beads a are optically identified. can do. Therefore, the glass beads a
The laser light applied to the main body of the
Go straight in the direction. On the other hand, since the through hole b provided in the glass bead a has a different refractive index from the liquid 1 or the like, the laser light incident on the cavity formed by the through hole b does not go straight in the y direction and is refracted. Scatter.

In the present invention, such transmitted light of the glass beads a is received by the light receiving means 4 and the output of the light receiving means is inputted to the detecting means 5, so that the detecting means 5 changes the intensity of the transmitted light from the glass. The shape of the inner diameter of the bead a is measured.

Specifically, the light receiving means 4 magnifies the laser light incident from the slit 41 by the convex lens 43 and receives it by each of the optical sensors 44a and 44b of the two-divided optical sensor 44. The detection means 5 compares the light amounts of the transmitted light received by the respective optical sensors 44a and 44b, and compares the comparison results (that is,
The shape of the inner diameter of the glass bead a is measured from the intensity of received light of each of the optical sensors 44a and 44b.

That is, in the process of scanning in the x direction by the driving means 6, when the slit 41 is in a position facing the main body of the glass beads a, the laser light emitted from the light projecting means 3 is refracted. Without passing through the liquid 1 or the glass bead a main body and enter the slit 41, the amount of laser light received by each of the optical sensors 44a and 44b is uniform, but the slit 41 is scanned by scanning in the x direction. Is glass beads a when viewed from the y direction
When facing the position corresponding to the boundary between the main body and the cavity (that is, the ridgeline of the inner diameter of the glass bead a), the laser light incident on the glass bead a is refracted at the ridgeline portion,
The light amount of each optical sensor 44a, 44b varies.

The detecting means 5 detects the position of the ridgeline of the inner diameter of the glass beads a based on such variations in the amount of received light.

As described above, according to the apparatus of the present invention, the light projecting means 3 and the light receiving means 4 are scanned in the radial direction of the glass beads a (direction of arrow x), so that the ridgeline of the inner diameter of the glass beads a is detected. Since the position can be detected, the unevenness of the ridge and the bending of the through hole b can be measured by further scanning at the detected position of the ridge in the axial direction of the glass beads a (arrow z direction).

Although not particularly shown in this embodiment, the driving means 6 is provided with an actuator for rotating the glass beads a around the axis, so that the glass beads a are rotated around the axis at the detected ridge line position. By doing so, the distortion (unevenness) of the cross-sectional shape of the through hole b can also be measured.

Embodiment 2 Next, another embodiment of the present invention will be described with reference to FIG. The apparatus shown in FIG. 3 is a modified example of the apparatus of the above-described first embodiment, and specifically, an optical system for measuring the inner diameter of the glass beads a is modified.

That is, in the apparatus of the first embodiment, the inner diameter was measured from the transmitted light of the glass beads a, but in the present embodiment, the reflected light reflected by the ridgeline of the inner diameter of the glass beads a is used to make the glass beads a. Measure the shape of the inner diameter of. Therefore, in this embodiment, the light projecting unit 3, the light receiving unit 4, the detecting unit 5, the driving unit 6, and the control unit 7 in the first embodiment are modified.

Specifically, in the device shown in this embodiment,
Liquid 1 with the same refractive index as the glass beads a to be measured
A container 2 for containing the liquid 1, and a light projecting means 3'for irradiating the glass beads a immersed in the liquid 1 with light.
Light receiving means 4'for receiving and photoelectrically converting the reflected light reflected by the ridgeline of the cavity inside the glass beads a, and detecting means 5'for detecting the shape of the cavity of the glass beads a from the output of this light receiving means. A driving means 6'for synchronously moving the light projecting means 3'and the light receiving means 4'in a predetermined scan direction, a control means 7 for controlling each part of the apparatus, and a glass bead a for rotation about an axis. The rotation drive means 9 is provided as a main part.

The light projecting means 3'is a light source for irradiating the glass beads a with light from the side surface of the through hole b through the plano-convex lens 10 as shown in the figure. Similar to the first embodiment, the light source is a laser light source such as an argon ion laser.

On the other hand, the light receiving means 4'is for receiving the laser light reflected by the ridgeline of the inner diameter of the glass bead a through the plano-convex lens 10 and the reflection plate 11, and in this embodiment. Then, as the light receiving means 4 ', a four-division optical sensor as shown is used.

As is well known, the four-division photosensor is composed of four photosensors 4a to 4d arranged vertically and horizontally, and each of the photosensors 4a to 4d has a quantity of light (light intensity). ), An electric signal is output (photoelectric conversion).

Further, the convex lens 10 is immersed in the liquid 1 so as to face the glass beads a as shown in the figure, and the convex lens 10 is filled with the liquid 1 on the light projecting means 3'and the light receiving means 4 '. A waterproof cover 12 is attached so as not to enter.

The detecting means 5'measures the inner diameter of the glass beads a on the basis of the light receiving means output from the light receiving means 4 ', and specifically, the four-division optical sensor 4'.
The shape of the inner diameter of the glass bead a is measured from the distribution of the amount of light received in the manner described below. Also in this embodiment, a digital signal is input to the detecting means 5'from the 4-division optical sensor 4'through an A / D conversion circuit (not shown).

The driving means 6'is an actuator for synchronously moving the light projecting means 3'and the light receiving means 4'in a predetermined scanning direction, and the operation of this actuator is controlled by the control means 7 '. It is controlled.

Specifically, this actuator is arranged so that the light projecting means 3'and the light receiving means 4'can scan the whole glass beads a in the radial direction (x direction) of the glass beads a. In addition to being movable in the direction (z direction), it is also movable in the y direction shown in FIG. 3 so that the focus of the convex lens 10 can be adjusted.

The control means 7'is composed of a microcomputer provided with a control program for controlling the operation of each part of the apparatus. Specifically, the operation control of the drive means 6'and the projection means 3'are performed. In addition to the control of turning on / off, various processes such as the detection process in the detecting means 5'are executed.

Therefore, in the apparatus having the above-mentioned structure according to the second embodiment, the inner diameter of the glass beads a is measured as follows.

First, at the start of the measurement, sealing plugs 8 for sealing the through hole b are attached to the openings at both ends of the through hole b of the glass bead a to be measured, and the cavity formed in the glass bead a is attached. The point of sealing is similar to that of the first embodiment.

Then, when the through hole b of the glass bead a is sealed, then the sealed glass bead a is immersed in the liquid 1 filled in the container 2, and the light projecting means 3'is turned on in this state. Then, the glass beads a are irradiated with laser light, and the reflected light is received by a four-division optical sensor (light receiving means) 4 '.

At this time, in the present embodiment, the outputs of the optical sensors 4a to 4d of the 4-division optical sensor 4'are averaged, in other words, the optical sensors 4 of the 4-division optical sensor 4 '.
The drive control (drive control in the x and y directions) of the drive means 6'is performed so that the light amount distribution received by a to 4d becomes uniform, and thereafter the scanning in the z direction is performed at that position.

That is, in the present embodiment, by performing scanning in the z direction at that position, when the inner diameter of the glass beads a is uneven, the direction of the reflected light is deviated due to the unevenness, First, each of the above optical sensors 4a
The position where the light amount distribution of 4d is made uniform is detected, scanning is performed in the z direction in that state, and the disturbance of the direction of the reflected light caused by the unevenness of the inner diameter is detected in each of the four-division optical sensor 4 '. The unevenness of the inner diameter of the glass beads a is measured by detecting with 4a to 4d.

Although not particularly shown in the present embodiment, the driving means 6 ′ is provided with an actuator (rotational driving means) for rotating the glass beads a around the axis so that the glass beads a are rotated while z. It is also possible to detect the bending of the inner diameter of the glass beads a by scanning in the direction.

Note that the above-described embodiment merely shows a preferred embodiment of the present invention, and the present invention is not limited to this, and various design changes can be made within the scope.

For example, in the above-mentioned embodiment, the case where the scanning is performed by moving the light projecting means 3 and the light receiving means 4 is shown, but the glass beads a to be measured are held by a holder or the like. Alternatively, the holder may be moved in the predetermined scanning direction to perform scanning.

[0058]

As described in detail above, according to the present invention,
Hollow transparent object such as glass beads is hermetically sealed and immersed in a liquid having the same refractive index as the object to be measured. In this state, the object to be measured is irradiated with light to form the inner diameter of the object to be measured. Is detected by an optical method, it is possible to detect unevenness or bending of the inner diameter of glass beads such as glass beads having a small size.

[Brief description of drawings]

FIG. 1 is a front view showing a schematic configuration of an inner diameter measuring device for a hollow transparent body according to the present invention.

FIG. 2 is a side view showing a schematic configuration of an optical system of the same inner diameter measuring device.

FIG. 3 is an explanatory diagram showing a schematic configuration of another embodiment of the inner diameter measuring device for a hollow transparent body according to the present invention.

FIG. 4 is a perspective view showing an appearance of glass beads as an object to be measured.

[Explanation of symbols]

1 liquid (liquid means) 2 containers 3,3 'Projection means 4,4 'Light receiving means 5,5 'detection means 6,6 'drive means 7,7 'control means 8 Sealing plug 10 Plano-convex lens 11 reflector 12 waterproof cover 31 light source 32 concave lens 33 Plano-convex lens 41 pinhole 42 cases 43 convex lens 44 2-split optical sensor 44a, 44b Optical sensor a Glass beads (measurement object) b Through hole

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoji Hasebe             2-16-1 Ominemoto-cho, Hirakata-shi, Osaka             In ceremony company Sentech F term (reference) 2F065 AA01 AA12 AA13 AA20 AA46                       AA49 AA60 BB08 BB22 CC23                       DD03 FF41 FF49 FF65 FF67                       GG05 HH03 HH15 JJ22 JJ23                       LL09 LL30 MM04 MM14 MM24                       MM28 PP03 PP13 QQ15 QQ25                 2H036 LA00 MA06 MA07 QA13 QA17                       QA18

Claims (13)

[Claims] 1. A method for measuring the shape of the inner diameter of an object to be measured, which comprises a hollow transparent body, wherein an opening of the object to be measured is closed to close a cavity in the object to be measured, and the closed object is sealed. A hollow characterized by immersing a measurement object in a liquid having the same refractive index as that of the measurement object, and irradiating the measurement object with light in this state to detect the shape of the inner diameter of the measurement object by an optical method. Measuring method of inner diameter of transparent body. 2. A method for measuring the shape of the inner diameter of an object to be measured, which comprises a hollow transparent body, wherein an opening of the object to be measured is capped to close a cavity inside the object to be measured, and the closed object is sealed. The object to be measured is immersed in a liquid having the same refractive index as the object to be measured, and in this state, the object to be measured is irradiated with light and the transmitted light is received to detect the shape of the inner diameter of the object to be measured from its strength. A method for measuring the inner diameter of a hollow transparent body, comprising: 3. The hollow according to claim 2, wherein when the object to be measured is a hollow transparent body having a through hole, the light is irradiated so as to be orthogonal to the axial direction of the through hole. Measuring method of inner diameter of transparent body. 4. The hollow transparent body according to claim 3, wherein the transmitted light is received while scanning the light receiving means for receiving the transmitted light in the radial direction and the axial direction of the through hole of the object to be measured. How to measure the inner diameter of the body. 5. A method for measuring the shape of the inner diameter of an object to be measured, which comprises a hollow transparent body, wherein an opening of the object to be measured is capped to close a cavity in the object to be measured, and the closed object is measured. The object to be measured is dipped in a liquid having the same refractive index as the object to be measured, and the object to be measured is irradiated with light in this state, and the reflected light reflected by the ridge of the cavity of the object to be measured is received. Then, the shape of the inner diameter of the object to be measured is detected from its strength and weakness, and a method for measuring the inner diameter of the hollow transparent body. 6. The inner diameter measurement of a hollow transparent body according to claim 4, wherein when the object to be measured is a hollow transparent body having a through hole, the light is irradiated from a side surface of the through hole. Method. 7. The inner diameter of the hollow transparent body according to claim 6, wherein the light receiving means for receiving the reflected light receives the reflected light while scanning in the axial direction of the through hole of the object to be measured. Measuring method. 8. The inner diameter of the hollow transparent body according to claim 6, wherein the reflected light is received while rotating the object to be measured around the axis of the through hole when the reflected light is received. Measuring method. 9. A device for measuring the shape of the inner diameter of an object to be measured which is a hollow transparent body, and a liquid means which is made of a liquid having the same refractive index as that of the object to be measured and into which the object to be measured is immersed. A light projecting unit that irradiates the measured object immersed in the liquid means with light, and a light projecting unit that is provided so as to face the light projecting unit with the measured object interposed therebetween, and receives light that has passed through the measured object. And a photoelectric conversion means, a detecting means for detecting the shape of the cavity in the object to be measured from the output of the light receiving means, and a driving means for synchronously moving the light projecting means and the light receiving means in the scanning direction. An inner diameter measuring device for a hollow transparent body, which is characterized in that 10. The inner diameter measuring device for a hollow transparent body according to claim 9, wherein said light receiving means comprises a two-division optical sensor in which a pair of optical sensors are arranged in parallel at a predetermined interval. 11. An apparatus for measuring the shape of the inner diameter of an object to be measured which is a hollow transparent body, and a liquid means which is made of a liquid having the same refractive index as that of the object to be measured and into which the object to be measured is immersed. A light projecting means for irradiating the measured object immersed in the liquid means with light, and a light receiving means for receiving reflected light of the irradiated light reflected by the ridge of the cavity of the measured object and photoelectrically converting the reflected light. A hollow having a detecting means for detecting the shape of the cavity in the object to be measured from the output of the light receiving means, and a driving means for synchronously moving the light projecting means and the light receiving means in a predetermined scan direction. An inner diameter measuring device for transparent bodies. 12. An inner diameter measuring device for a hollow transparent body according to claim 11, further comprising a rotation driving means for rotationally driving the object to be measured. 13. The inner diameter measuring device for a hollow transparent body according to claim 11 or 12, wherein said light receiving means comprises a four-division optical sensor in which optical sensors are arranged vertically and horizontally.