JPH06194127A - Glass fiber length measuring method and device therefor - Google Patents

Abstract

PURPOSE:To provide a method and a device for measuring the length of a glass fiber with high accuracy. CONSTITUTION:Both end faces 31 of a glass fiber 3 are illuminated by the light going out of the tips 163 of light guides 162, and the illuminated end faces 31 of the glass fiber 3 are respectively photographed by CCD cameras. The signals of images photographed by the respective CCD cameras 14 are image- processed to extract high contrast picture element parts in the respective photographed images and to detect the picture elements to be the center-of- gravity of the respective picture element parts and the two-dimensional coordinates, in the above-mentioned photographed images, of the respective picture elements to be the center of gravity. The length L of the glass fiber 3 is then measured on the basis of the detected two-dimensional coordinates of the respective center-of-gravity picture elements and the distance L2 between the photographic lens systems of the respective CCD cameras 14.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method and apparatus for measuring the length of glass fibers.

[0002]

2. Description of the Related Art When manufacturing an optical fiber bundle, a glass member is melted and drawn to obtain a glass fiber having a predetermined wire diameter, and then the glass fiber is cut into a predetermined length to obtain a single fiber. In addition, the thus obtained single fibers are bundled in a unit of tens of thousands with their end faces aligned, and a large number of the bundled single fibers are heated again and pulled out to form an optical fiber bundle having a desired diameter. .

By the way, in order to obtain a high quality optical fiber bundle,
It is required to bundle a large number of monofilaments in an orderly and orderly manner. Therefore, conventionally, an inspection as to whether or not the large number of single fibers are regularly arranged is performed by visually observing whether or not the image guided by the large number of bundled single fibers is distorted. . Then, in this inspection, when the image is distorted, it is determined that a large number of single fibers are not regularly arranged.

[0004]

However, if the length of each single fiber is not uniform, the end faces of the single fiber bundle in which a large number of them are bundled have unevenness, and the unevenness leads to an image guided by the single fiber bundle. When the image is distorted in the above inspection, the cause is that a large number of single fibers are not regularly aligned and bundled, or the length of each single fiber is distorted. However, there is a problem in that it is impossible to specify whether or not the end faces of the single fiber bundle in which a large number of them are bundled are not aligned.

Therefore, in order to surely judge the quality of the aligned state of the single fiber by the inspection, it is desirable to maintain the length of the single fiber with high precision in manufacturing the single fiber. In response to the above, it would be convenient if the length of manufactured monofilament can be measured with high accuracy and the monofilament having a length outside the predetermined standard can be removed.

Incidentally, not only the single fiber constituting the optical fiber bundle but also the glass fiber which is a finished product by itself,
Of course, it is convenient if the length can be measured with high accuracy.

The present invention has been devised in view of the above circumstances, and an object of the present invention is to measure the lengths of various glass fibers such as glass fibers forming an optical fiber bundle with high accuracy. Another object of the present invention is to provide a glass fiber length measuring method and device.

[0008]

The invention according to claim 1 for achieving the above object relates to a method for measuring the length of a glass fiber having both ends, wherein each end of the glass fiber is illuminated, and Each end of the illuminated glass fiber is photographed by an individual TV camera, the signal of the image taken by each TV camera is image-processed, and the coordinates of the end of the glass fiber in each image are detected. Then, the length of the glass fiber is measured based on the coordinates in the captured images of the ends of the detected glass fiber and the distance between the television cameras. .

The invention of claim 2 relates to a device for measuring the length of a glass fiber which has both ends and extends linearly, and is movable in a direction parallel to the extending direction of the glass fiber. A pair of television cameras, each of which is arranged and directs its respective end portions in a direction intersecting with the extending direction of the glass fiber, and the optical axis directions of the respective photographing lens systems are parallel to each other, and the both end portions of the glass fiber. Illuminating means for illuminating, image processing means for performing image processing on the signal of the captured image of each of the television cameras capturing the image of each end of the glass fiber illuminated by the illuminating means, and image processing by the image processing means. Based on the result, coordinate detection means for detecting the coordinates of each end of the glass fiber in the image taken by each television camera, and the gas detected by the coordinate detection means. And coordinates in the in the taken image of each end of the Sufaiba, based on said interval of the television camera in a direction along the extending direction of the glass fiber,
And a calculating means for calculating the length of the glass fiber.

[0010]

The method for measuring the length of a glass fiber according to the present invention will be described below. FIG. 1 is an explanatory diagram showing a schematic configuration of a mechanical portion of a glass fiber length measuring device to which the method of the present invention is applied.

In FIG. 1, 1 is a glass fiber length measuring device, 3 is a transparent linear glass fiber, a core,
A glass member having a triple structure of a clad and an acid-soluble glass is drawn and drawn out, and cut into a predetermined length L. A conveyor 5 conveys the glass fiber 3 from a glass fiber manufacturing apparatus (not shown) to an optical fiber bundle manufacturing apparatus (not shown) in a direction orthogonal to the paper surface direction of FIG. The glass fiber 3 is placed on the conveyor surface 51 of the conveyor 5 so as to extend horizontally in a direction orthogonal to the conveyor direction of the conveyor 5.

The glass fiber length measuring device 1 measures the length L of the glass fiber 3 and is arranged above the conveyor 5 and has the guide rail 11 and the horizontal moving frame 1 shown in FIG.
2, the vertical movement frame 13, the CCD camera 14, the support frame 15, and the illumination unit 16, and the monitor television 1 shown in FIG.
7, an image processing unit 18, and a fiber length measuring unit 19.

As shown in FIG. 1, the guide rail 11 extends in the horizontal direction parallel to the conveying surface 51 of the conveyor 5 and orthogonal to the conveying direction. A pair of horizontal moving frames 12 are provided as shown in FIG.
1 is supported so as to be movable in the horizontal direction.

As shown in FIG. 1, a pair of vertical moving frames 13 are provided, and each of the horizontal moving frames 1 is provided by a screw 132 inserted in an elongated hole 131 whose longitudinal direction is the vertical direction.
It is attached to 2. That is, each vertical moving frame 13 is supported by each horizontal moving frame 12 so as to be vertically movable.

CCD camera 14 (corresponding to a television camera)
As shown in FIG. 1, a pair is provided, each of which is held by each vertical moving frame 13, and its photographing lens system 141 is directed to the conveyor 5 portion vertically below. That is, each C
The taking lens system 141 of the CD camera 14 points the conveyor 5 in a direction intersecting the extending direction of the glass fiber 3 on the conveyor 5, and the optical axis directions of the taking lens systems 141 are parallel to each other. In this embodiment, each C
The angle of view of the CD camera 14 is set to 3 ° to 5 °.

As shown in FIG. 1, a pair of support frames 15 are provided and attached to the side portions of each vertical moving frame 13. Each support frame 15 extends in the vertical direction downward from the side portion of each vertical movement frame 13, and has a substantially L-shape with its tip bent inward. A support portion 151 is formed at the tip of each bent support frame 15.

As shown in FIG. 1, the illuminating section 16 (corresponding to illuminating means) comprises a light source 161 and a pair of light guides 162 connected to the light source 161. As shown in FIG. 1, the light guides 162 are attached to the support portions 151 of the support frames 15 so as to face each other and be on the same straight line. Each light guide 1
62 guides the light from the light source 161 and directs the light to the tip 16
Emit from 3.

Image signals photographed by the CCD cameras 14 are input to the monitor television 17, and the photographed images by the CCD cameras 14 are displayed here.
Note that, in FIG. 2, for the sake of simplification, the images taken by both CCD cameras 14 are shown as being combined and displayed on one monitor television 17, but in reality, the images taken by each CCD camera 14 are individually displayed. It is displayed on the monitor TV 17. The image signals photographed by the CCD cameras 14 are input to the image processing section 18, where the image signals from the CCD cameras 14 are subjected to image processing to extract pixel portions with high contrast in the image. Be seen.

The fiber length measuring section 19 is connected to the image processing section 18, as shown in FIG. The fiber length measuring unit 19 is composed of, for example, a CPU and the like, and the fiber length measuring unit 19 includes the CCD cameras 14 which are determined by a horizontal interval L1 between the horizontal moving frames 12 shown in FIG. L2 between the taking lens systems 141 (FIG. 1) of
And two-dimensional coordinate data of each pixel in the image taken by each CCD camera 14 are held. In addition, each C
The distance L2 between the taking lens systems 141 of the CD camera 14 is
After positioning each horizontal moving frame 12 with respect to the guide rail 11 and fixing the position of each CCD camera 14 in the horizontal direction, measurement is performed by any means, for example, operation of a keyboard connected to the fiber length measuring unit 19 or the like. Is input to the fiber length measuring unit 19.

The fiber length measuring unit 19 is supplied with data of a pixel portion having a high contrast in an image picked up by each CCD camera 14 extracted by the image processing unit 18,
The center of gravity of each pixel portion is detected based on the data of each pixel portion, and each CC of each pixel that becomes the center of gravity is detected.
Two-dimensional coordinates in the image captured by the D camera 14 are detected.

Further, the distance L between the two-dimensional coordinate of each detected pixel serving as the center of gravity in each of the photographed images and the photographed lens system 141 of each of the CCD cameras 14 held.
2, the actual length between each pixel, which is the center of gravity of the pixel portion with high contrast, is calculated. In this embodiment, the fiber length measuring section 19 corresponds to the coordinate detecting means and the calculating means.

Next, the case where the length L of the glass fiber 3 is measured by the glass fiber length measuring device 1 of the present embodiment having the above-mentioned structure will be described. First, the pair of horizontal moving frames 12 are moved along the guide rails 11, and the supporting portions 151 of the supporting frames 15 attached to the side portions of each horizontal moving frame 12 face both sides of the conveyor surface 51 of the conveyor 5. Tip 1 of light guide 162 attached to each support 151
63 indicates both end surfaces 31 of the glass fiber 3 on the conveying surface 51.
As shown in FIG. 1, each horizontal moving frame 12 is positioned so that both end faces 31 of the glass fiber 3 are positioned substantially at the center of the photographing area of each CCD camera 14 held by the pair of vertical moving frames 13. To do.

Then, the tightening of the screws 132 is loosened, and each vertical moving frame 13 is moved along the elongated hole 131, and the both end faces 31 of the glass fiber 3 are moved by the CCD camera 14 held by each vertical moving frame 13. When taking a picture, each vertical moving frame 13 is positioned so that the focus thereof matches the both end surfaces 31, and the screw 132 is tightened again. Positioning of the horizontal moving frame 12 and the vertical moving frame 13 is completed, and each C
If the CD camera 14 is fixed, each CCD camera 1
The distance L2 between the four taking lens systems 141 is measured by an arbitrary means and input to the fiber length measuring unit 19.

After the above-mentioned work is completed, when the glass fiber 3 is started to be conveyed by the conveyor 5 from the glass fiber manufacturing apparatus (not shown) to the optical fiber bundle manufacturing apparatus, both end surfaces 31 of the glass fiber 3 being conveyed are transferred. The conveyor 5 is temporarily stopped at a position facing each of the light guides 162.
While the conveyor 5 is stopped, both end surfaces 31 of the glass fiber 3 are illuminated by the light from the light source 161 guided by each light guide 162 and emitted from the tip 163 thereof.

When both end faces 31 of the glass fiber 3 are illuminated by the light from the light source 161, each end face 31 of the glass fiber 3 is photographed by each CCD camera 14. In this case, since the glass fiber 3 is transparent, the glass fiber 3 is not actually photographed, and only the thin line-shaped light of each end face 31 that is illuminated by the light from the light source 161 and diffusely reflected is used in each CCD camera. Photographed by 14.

The image signal from each CCD camera 14 which has captured the fine linear light diffusedly reflected by both end faces 31 of the glass fiber 3 is image-processed by the image processing section 18, and the contrast in the image captured by each CCD camera 14 is high. Only the pixel portion is extracted. The extracted data of each pixel portion is input to the fiber length measuring unit 19, where the pixel serving as the center of gravity of each extracted pixel portion and the two-dimensional coordinates of each pixel serving as the center of gravity in each captured image are input. And are detected. That is, the fiber length measuring unit 19 detects the two-dimensional coordinates of each end surface 31 of the glass fiber 3 in the image captured by each CCD camera 14.

The fiber length measuring unit 19 further inputs in advance the two-dimensional coordinates of the detected end faces 31 of the glass fibers 3 and the two-dimensional coordinates of the central pixel in the image captured by each CCD camera 14. The distance between both end faces 31 of the glass fiber 3, that is, the length L of the glass fiber 3 is calculated based on the held distance L2 between the taking lens systems 141 of the respective CCD cameras 14.
As a specific calculation method, for example, since the distance between the center pixels in the image captured by each CCD camera 14 is equal to the distance L2, the two-dimensional coordinates of each center pixel and each end face 31 of the glass fiber 3 are calculated. The length L of the glass fiber 3 is calculated by increasing or decreasing the value of the distance corresponding to the deviation from the distance L2.

As described above, in this embodiment, both end surfaces 31 of the glass fiber 3 are illuminated with the light emitted from the tip 163 of the light guide 162, and each end surface 31 of the illuminated glass fiber 3 is CCD. The image of the image captured by each CCD camera 14 is image-processed by the image processing unit 18 while the image is captured by the camera 14, and the pixel portion with high contrast in each captured image is extracted to be the center of gravity of each pixel portion. The fiber and the two-dimensional coordinates of each pixel serving as the center of gravity in each photographed image are detected by the fiber length measuring unit 19, and the two-dimensional coordinates of each detected centroid pixel and the photographing lens system of each CCD camera 14 are detected. Based on the distance L2 between 141,
The length L of the glass fiber 3 is measured by the fiber length measuring unit 19
The length L of the glass fiber 3 is
Can be measured with high accuracy.

Further, each CCD camera 14 needs to photograph only one end face 31 of the glass fiber 3 and not the entire glass fiber 3. Therefore, the angle of view of the photographing lens system 141 is 3 ° to 5 °, which is narrower than usual. Therefore, an image with less distortion at the peripheral portion of the photographing area can be displayed on each CCD camera 1.
4, the two-dimensional coordinates of both end surfaces 31 of the glass fiber 3 can be detected with high accuracy, and the measurement accuracy of the length L of the glass fiber 3 can be further improved. Furthermore, since the measurement accuracy can be freely changed by changing the lens magnification of the taking lens system 141, the length measurement can be easily performed with desired accuracy.

Further, according to the glass fiber length measuring apparatus 1 of this embodiment, the length L of the glass fiber 3 can be measured in a non-contact manner, so that, for example, an optical fiber bundle is manufactured from the glass fiber manufacturing apparatus (not shown). It is suitable for measuring the length L of the glass fiber 3 conveyed to the device on the conveyance path. And if it does so, the glass fiber 3 of the nonstandard length will be discarded on the conveyance path based on the measurement result, the unevenness | corrugation of the glass fiber 3 regarding a length will be eliminated, and the length of the length conforming to the standard will be eliminated. It becomes possible to supply only the glass fibers 3 to the optical fiber bundle manufacturing apparatus (not shown), and when a large number of glass fibers 3 are bundled in order to obtain the optical fiber bundles, the end faces of the glass fiber bundles become uneven. You can avoid it.

As a result, when an image is guided by the glass fiber bundle in order to inspect the aligned state of a large number of bundled glass fibers 3, the image is distorted due to the unevenness of the end face of the glass fiber bundle. Therefore, the aligned state of a large number of bundled glass fibers 3 can be reliably determined by inspecting the presence or absence of distortion of the guided image. That is, the method and apparatus of the present invention are also suitable for performing the above-mentioned inspections and the like when manufacturing an optical fiber bundle.

Further, according to the glass fiber length measuring apparatus 1 of the present embodiment, the guide rail 11 is extended in parallel with the extending direction of the glass fiber 3, and a pair of horizontal movable along the guide rail 11. The moving frame 12 has a vertical moving frame 13
Since each CCD camera 14 is held via the C camera, each C camera is based on the position on the guide rail 11 of each horizontal moving frame 12.
The distance between the CD cameras 14, that is, the distance L2 between the taking lens systems 141 of each CCD camera 14 can be easily detected, and each CCD camera 14 can be set to a glass according to the width of the conveyor 5 and the length of the glass fiber 3. It can be easily moved along the extending direction of the fiber 3.

In the present embodiment, the case where the optical axis directions of the taking lens systems 141 of the CCD cameras 14 are parallel to each other has been described, but the CCD cameras 14 are inclined and the both end faces 31 of the glass fiber 3 are directed. In such a case, in consideration of the inclination of each CCD camera 14 and the distance between each end surface 31 of the glass fiber 3 and the taking lens system 141 of each CCD camera 14, the glass fiber 3 The length L can be calculated by the fiber length measuring unit 19. Further, in the present embodiment, the CCD camera 14 photographs the both end surfaces 31 of the glass fiber 3, but C
The both end surfaces 31 of the glass fiber 3 may be photographed by a normal television camera other than the CD camera.

Further, the measuring apparatus for carrying out the method of the present invention is not limited to the one shown in the present embodiment, and the method and apparatus of the present invention is not limited to glass as a single fiber constituting an optical fiber bundle. It goes without saying that the present invention can be applied not only to measuring the length of the fiber but also to measuring the length of the glass fiber which is a finished product by itself.

[0035]

As described above, according to the present invention, there is provided a method for measuring the length of a glass fiber having both ends,
Each end of the glass fiber is illuminated, each end of the illuminated glass fiber is photographed by an individual television camera, and the image photographed by each television camera is image-processed, Detecting the coordinates of the end of the glass fiber, and measuring the length of the glass fiber based on the coordinates in the image of each end of the detected glass fiber and the distance between the television cameras. I chose Therefore, it is possible to measure the lengths of various glass fibers such as the glass fibers forming the optical fiber bundle with high accuracy.

Further, according to the present invention, since the length of the glass fiber can be measured in a non-contact manner, for example, in measuring the length of the glass fiber supplied to the optical fiber bundle manufacturing apparatus in its supply path. Furthermore, when manufacturing an optical fiber bundle, when inspecting the alignment state of a large number of bundled glass fibers, it is possible to judge the quality of the alignment state by the presence or absence of distortion of the image guided by the glass fiber bundle. It is suitable for reliable operation.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a schematic configuration of a mechanical portion of a glass fiber length measuring device to which the method of the present invention is applied.

FIG. 2 is an explanatory diagram showing a partial block diagram of a configuration of a signal processing portion in the glass fiber length measuring device of FIG.

[Explanation of symbols]

 1 Glass Fiber Length Measuring Device 14 CCD Camera (TV Camera) 141 Photographing Lens System 16 Illuminating Unit (Illuminating Means) 18 Image Processing Unit (Image Processing Means) 19 Fiber Length Measuring Unit (Coordinate Detecting Means, Calculating Means) 3 Glass Fiber 31 Glass fiber end face L Glass fiber length L2 Distance between shooting lens systems (interval between TV cameras)

Claims (2)

[Claims] 1. A method for measuring the length of a glass fiber having both ends, wherein each end of the glass fiber is illuminated, and each end of the illuminated glass fiber is photographed by an individual television camera. Then, image processing is performed on the signal of the image captured by each of the television cameras to detect the coordinates of the end portion of the glass fiber in each captured image, and the captured image of each end portion of the detected glass fiber. The glass fiber length measuring method is characterized in that the length of the glass fiber is measured based on the inside coordinates and the distance between the television cameras. 2. An apparatus for measuring the length of a glass fiber which has both ends and extends linearly, the device being movably arranged in a direction parallel to the extending direction of the glass fiber. A pair of television cameras, each of which has its end portion oriented in a direction intersecting the extending direction, and whose optical axis directions of the photographing lens systems are parallel to each other, and an illumination unit that illuminates both end portions of the glass fiber, Image processing means for performing image processing on the signal of the captured image of each television camera that has captured the image of each end of the glass fiber illuminated by the illumination means, and based on the image processing result by the image processing means, Coordinate detecting means for detecting the coordinates of each end of the glass fiber in the image captured by the television camera, and the end of each glass fiber detected by the coordinate detecting means. And a calculating unit that calculates the length of the glass fiber based on the coordinates in the captured image and the distance between the television cameras in the direction along the extending direction of the glass fiber. Fiber length measuring device.