JP2008196930A - Optical measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical measuring device having a simple configuration, capable of miniaturizing a measuring part. <P>SOLUTION: An operation control part 120 controls the on/off state of an optical switch part 104 with a pattern scanning a measuring object 102. Measuring light from a light source 130 is irradiated to the measuring object 102 through the optical switch part 104, the first optical fiber bundle 108 and a concave lens 115, and the measuring light reflected by the measuring object 102 is detected by a photodetection part 105 through a light receiving lens 114 and the second optical fiber bundle 107, and detected by a photodetection part 106 through a light receiving lens 116 and the second optical fiber bundle 109, and the operation control part 120 calculates a three-dimensional shape or the like of the measuring object 102 based on the measuring light detected by photodetection parts 105, 106. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is an optical measuring device that irradiates a measurement object with the measurement light, detects the measurement light reflected by the measurement object, and measures the shape or the like of the measurement object based on the detected measurement light About.

  Conventionally, the measurement light generated from a light source such as a semiconductor laser is irradiated onto the measurement object, and the measurement light reflected by the measurement object is detected, so that the three-dimensional shape of the measurement object or the predetermined position can be used. An optical measuring device that measures the distance to a measurement object has been developed (see, for example, Patent Document 1).

In the conventional optical measurement apparatus, the measurement light from the light source is irradiated to the measurement object through the space, and the measurement light reflected by the measurement object is detected by the light detection element through the space. Therefore, the shape of the measurement unit including the light source and the light detection element is increased.
Therefore, when measuring the inner surface shape of the deep hole, etc., there is a problem that the measurement part cannot be inserted into the deep hole and cannot be measured.

  As a method for solving this problem, it is conceivable to provide a reflection mirror or the like that reflects measurement light to the measurement target side, and to perform measurement by inserting the reflection mirror into the deep hole. Since a motor for driving the mirror, a control circuit, and the like are required, the structure is complicated and it is difficult to reduce the size.

JP 2006-90879 A

  An object of the present invention is to provide an optical measuring device that can be downsized with a simple configuration.

  According to the present invention, the light output means for irradiating the measurement light to the measurement object via the first optical fiber bundle and the mutual positional relationship are known and the light output means is arranged at a position unrelated to the position of the light output means. A plurality of light detection means that detect the measurement light reflected by the measurement object via a second optical fiber bundle, and the measurement object based on the measurement light detected by the plurality of light detection means There is provided an optical measuring device comprising a calculating means for calculating a characteristic relating to the length of the optical measuring device.

  The light output means irradiates the measuring object with measurement light via the first optical fiber bundle. A plurality of light detection means arranged at positions that are known to each other and are irrelevant to the position of the light output means, pass the measurement light reflected by the measurement object through the second optical fiber bundle. To detect. The calculation means calculates a characteristic related to the length of the measurement object based on the measurement light detected by the plurality of light detection means.

The first optical fiber bundle and the second optical fiber bundle are configured such that the light output means side and the light detection means side are the same thickness as the measurement object side or thicker than the measurement object side, respectively. You may comprise so that it may become.
The first optical fiber bundle and the second optical fiber bundle may be configured by bundling a plurality of tapered optical fibers.

The light output means outputs the measurement light from the light source to the light source that outputs the measurement light to the first optical fiber bundle side and each optical fiber that constitutes the first optical fiber bundle. You may comprise so that the optical switch means turned on or off in order to selectively permeate | transmit or shield, and the control means which controls the said optical switch means on or off may be comprised.
Further, the light detection means may be configured to include a light detection element corresponding to each optical fiber constituting the second optical fiber bundle.

Further, the plurality of light detection means may be combined with one detection means.
Each of the light detection means may be constituted by a CMOS photosensor array, a CCD, or a PSD.

  According to the optical measurement device of the present invention, it is possible to reduce the size of the measurement unit with a simple configuration. In addition, measurement can be performed by setting the positional relationship between the light output means and the light detection means independently, so the degree of freedom of measurement is increased and it is possible to handle various measurements with a simple configuration. become.

Hereinafter, an optical measuring apparatus according to an embodiment of the present invention will be described with reference to the drawings. In addition, in each figure used by the following description, the same code | symbol is attached | subjected to the same part.
FIG. 1 is a perspective view showing a basic configuration of an optical measuring device according to a first embodiment of the present invention.
In FIG. 1, an optical switch portion 104 formed in a substantially square shape is integrally provided at the center of the translucent first support member 103, and the first support is sandwiched between the optical switch portions 104. A first light detection unit 105 and a second light detection unit 106 are integrally provided on both sides of the member 103.

  The optical switch unit 104 has a configuration in which a plurality of optical switch elements are arranged in a matrix (in the present embodiment, 256 each in the row and column directions (256 × 256 in total)). Each of the optical switch elements is configured to be in one of a state of transmitting incident light and a state of blocking light under the control of the arithmetic control unit 120.

  Each of the first and second light detection units 105 and 106 has the same number of light detection elements as the optical switch elements of the optical switch unit 104 in a matrix (in this embodiment, 256 each in the row and column directions (256 × 256)). As the first and second photodetection units 105 and 106, for example, a complementary metal oxide semiconductor (CMOS) type photosensor array (CMOS photosensor array), a CCD (Charge Coupled Device), or a PSD (Position Sensitive Detector). Etc.) can be used.

  The first end of the first optical fiber bundle 108 is integrally connected to a position corresponding to the optical switch 104 at the center of the first support member 103, and the first and second light detections at both ends of the first support member 103 are performed. The first end portions of the second optical fiber bundles 107 and 109 are integrally connected to positions corresponding to the portions 105 and 106, respectively.

Each optical switch element constituting the optical switch unit 104 is disposed so as to face the end part of each optical fiber constituting the first optical fiber bundle 108. In addition, the respective light detection elements constituting the first and second light detection units 105 and 106 are disposed so as to face the end portions of the respective optical fibers constituting the second optical fiber bundles 107 and 109, respectively. Yes.
The first optical fiber bundle 108 is configured such that the optical switch 104 side is thicker than the measurement object 102 side. The second optical fiber bundles 107 and 109 are configured such that the first and second light detection units 105 and 106 side is thicker than the measurement object 102 side.

FIG. 2 is a diagram illustrating the configuration of the optical fiber bundles 107 to 109. FIG. 2A is a view showing one optical fiber constituting the optical fiber bundle. The optical fiber 201 has a light guide portion 202 that guides light at the center thereof, and a covering portion 203 that covers the entire side surface with a uniform thickness so as to shield light from leaking from the side surface of the light guide portion 202. It has.
The light guide unit 202 is formed in a tapered shape, and the area of the first end 204 is larger (thicker) than the area of the second end 205. As a result, the optical fiber 201 itself is formed in a tapered shape. The measurement light incident from the first end portion 204 side is emitted from the second end portion 205 side, and the measurement light incident from the second end portion 205 side is emitted from the first end portion 204 side.

FIG. 2B is an explanatory diagram of an optical fiber bundle 212 configured by bundling a plurality of optical fibers 201, and the plurality of optical fibers 201 are arranged so that the cross section is substantially square (for example, in row and column directions). 5 shows an example of the optical fiber bundle 212 bundled by 256 (256 × 256).
Since each optical fiber 201 is tapered, an optical fiber bundle 212 in which the optical fibers 201 are bundled is also tapered. That is, the area of the first bundle end 213 bundled on the first end 204 side of the optical fiber 201 is larger than the area of the second bundle end 214 bundled on the second end 205 side of the optical fiber 201 ( It is configured to be thick).

  By forming the first optical fiber bundle 108 and the second optical fiber bundles 107 and 109 using the optical fiber bundle configured as described above, the first optical fiber bundle 108 is arranged on the optical switch 104 side on the measurement object 102 side. Further, the second optical fiber bundles 107 and 109 are configured so that the first and second light detection units 105 and 106 are thicker than the measurement target 102 side, respectively.

  In the case where it is sufficient to guide the measurement light, the first optical fiber bundle 108 has the same thickness on the optical switch 104 side as the measurement target 102 side, and the second optical fiber bundles 107 and 109 each have The first and second light detection units 105 and 106 may be configured to have the same thickness as the measurement target 102 side.

  When the light source 130 that outputs laser light is scanned so as to draw a figure 211 on a surface 210 orthogonal to the optical axis 200, the laser light from the light source 130 enters from the second bundle end 214 side of the optical fiber bundle 212. The light is emitted from the first bundle end 213 side through the optical fibers 201 constituting the optical fiber bundle 212.

  In-plane orthogonal to the optical axis 200 is provided with the photodetecting portions 215 having photodetecting elements (for example, 256 (256 × 256) in the row and column directions) corresponding to the respective optical fibers constituting the optical fiber bundle 212. By arranging the optical fiber bundle 212 on the first bundle end side, the laser beam corresponding to the figure 211 is detected as a figure 216 obtained by enlarging the figure 211 by the light detection unit 215. Become.

  Therefore, even in the case of measuring the shape of a small measurement object or the shape in a narrow groove, the first bundle is formed by configuring the second bundle end 214 side of the optical fiber bundle 212 arranged on the measurement object side in a small shape. Detection data such as an enlarged shape can be obtained on the end 204 side, and a narrow and deep hole or the like can be obtained using the photodetection unit 215 having a large size (in other words, the density of photodetection elements is low). It becomes possible to easily measure the inner surface shape and the like of the groove.

In FIG. 1 again, the second end of the optical fiber bundle 108 is formed integrally with a translucent support member 113. The second ends of the optical fiber bundles 107 and 109 are formed integrally with the translucent support members 111 and 112, respectively.
A concave lens 115 is disposed at a position facing the support member 113. Further, convex lenses 114 and 116 as light receiving lenses are disposed at positions facing the support members 111 and 112.

The support members 111 to 113, the concave lens 115, and the convex lenses 114 and 116 are formed integrally with the translucent support member 110. Thereby, the support member 103 and the support member 110 are integrally formed via the optical fiber bundles 107 to 109.
The measurement light output from the light source 130 enters the optical switch unit 104. The optical switch unit 104 is controlled by the arithmetic control unit 120 so that a predetermined switch element transmits the measurement light. The measurement light that has passed through the optical switch unit 104 is output to the measurement object 102 via the optical fiber bundle 108, the support member 113, and the concave lens 115.

For example, when the arithmetic control unit 120 sequentially controls the optical switch unit 104 from the upper side to the lower side so as to transmit the horizontal linear light, the measurement target 102 has the horizontal linear measurement light 117. , 118, 119 are scanned in this order.
The first and second light detection units 105 and 106 detect the measurement light reflected by the measurement object 102 via the corresponding light receiving lenses 114 and 115 and the optical fiber bundles 107 and 109, respectively.

  The light source 130 that outputs the measurement light includes the light receiving lens 114 and the support member 111 (in other words, the second end portion of the optical fiber bundle 107), and the light receiving lens 116 and the support member 112 (in other words, the first end of the optical fiber bundle 109). The two end portions are disposed irrespective of the mutual positional relationship. The light receiving lens 114, the support member 111 (in other words, the second end portion of the optical fiber bundle 107), the light receiving lens 116 and the support member 112 (in other words, the second end portion of the optical fiber bundle 109) have a mutual positional relationship. It is disposed in advance at a predetermined position.

Here, the light source 130, the optical switch unit 104, and the calculation control unit 120 constitute a light output unit, and the first and second light detection units constitute a light detection unit. The optical switch unit 104 constitutes optical switch means. The arithmetic control unit 120 constitutes a control unit and a calculation unit. The light receiving lenses 114 and 116 and the support members 111 and 112 constitute a measuring unit.
As described above, the positional relationship between the plurality of light detection means is arranged at a known predetermined position, and the light output means is arranged at an arbitrary position unrelated to the position of each light detection means. Established.

FIG. 3 is a diagram for explaining the measurement operation of the optical measurement apparatus according to the embodiment of the present invention.
In FIG. 3, when the measurement light is irradiated from the light source 130 to the measurement object 102, scattered light is generated at the irradiation position (measurement target position) on the surface of the measurement object 102, and a part thereof is reflected toward the light receiving lenses 114 and 116. To do. The measurement light reflected by the measurement object 102 is transmitted through the light receiving lenses 114 and 116, respectively, and the translucent support members 111 and 112 (in other words, the light is disposed corresponding to the light receiving lenses 114 and 116). Detected by the light detection units 105 and 106 via the second ends of the fiber bundles 107 and 109 and the optical fiber bundles 107 and 109.

Hereinafter, in order to simplify the description, a measurement example of a two-dimensional plane (Y-axis coordinates = constant) will be described, but measurement values can be obtained in the same manner for three dimensions. In FIG. 3, since the optical fiber bundles 107 and 109 are tapered, the image on the first end side is larger than the image on the second end side. n is the magnification when the image on the second end side is compared with the image on the first end side.
First, distances XLpi and XRpi (i = 1 in FIG. 3) from the detection values of the light detection units 105 and 106 to the detection point based on the X coordinate position corresponding to the light receiving lenses 116 and 114 are obtained.

  On the other hand, as a known value set in advance, the distance between the support member 111 (in other words, the second end of the optical fiber bundle 107) and the light receiving lens 114 is Dz, and the support member 112 (in other words, the first end of the optical fiber bundle 109). The distance between the two ends) and the light receiving lens 116 is Dz, and the distance between the light receiving lens 114 and the light receiving lens 116 is Dx.

The X and Z coordinates P1 (XL1, ZL1) of the point P1 on the measurement object 102 are obtained by the following two equations.
XL1 = Dx · Xλ1
ZL1 = Dx · Dz · Xμ1
However, Xλ1 and Xμ1 are based on the following equations.
Xλ1 = XLp1 / (XLp1-XRp1)
Xμ1 = 1 / (XLp1-XRp1)

  Therefore, nXLp1 and nXLRp1 are measured by the light detection units 105 and 106, and these measurement values nXLp1 and nXRp1 and known values Dz and Dx are used, and calculation processing is performed by the arithmetic control unit 120 using the above equations. Thus, the coordinates (XL1, ZL1) of the measurement target position on the measurement target 102 can be calculated with the center between the light receiving lenses 114 and 116 as the origin O.

  Further, by performing a geometric calculation process, the distance from a predetermined position (for example, the origin O) to the measurement object 102 can also be calculated. In addition, by measuring while using the measurement light output from the light source 130 to scan the measurement object 102, a plurality of points on the measurement object 102 are measured, and the three-dimensional shape of the measurement object 102 is calculated. Is possible.

As described above, since the optical measurement apparatus according to the present embodiment uses a tapered optical fiber bundle without using a reflection mirror or the like, the measurement unit on the measurement object 102 side can be reduced in size with a simple configuration. It becomes possible to easily measure the inner surface shape and the like of the deep groove.
In addition, since it is possible to perform measurement by setting the positional relationship between the light output means and the light detection means independently, the degree of freedom of measurement is increased, the size of the measurement unit can be reduced, and complex shapes can be measured. Characteristics relating to the length of the measurement object 102, such as measurement of the shape of the object (for example, the three-dimensional shape of the measurement object 102, the distance from the predetermined position to the measurement object 102, the measurement object 102 on the basis of the predetermined position It is possible to measure the coordinates of the predetermined point, the shape error between the predetermined shape and the measurement object 102).

FIG. 4 is a perspective view showing a basic configuration of an optical measuring apparatus according to the second embodiment of the present invention.
In the first embodiment, a plurality of light detection units 105 and 106 are used. However, in the second embodiment, a single light detection unit 402 attached to the support member 401 is used for measurement. It is configured to detect light. Similar to the light detection units 105 and 106, the light detection unit 402 has a configuration in which a plurality of (for example, 256 × 256) light detection elements are arranged in a matrix.

In the following, a description will be mainly given of portions where the second embodiment is different from the first embodiment.
In FIG. 4, the measurement light from the light source 130 is selected by the optical switch unit 104 under the control of the arithmetic control unit 120, and the pattern measurement light is measured via the optical fiber bundle 108, the support member 113, and the concave lens 115. The object 102 is irradiated.

The measurement light reflected by the measurement object 102 is input to the light detection unit 402 via the light receiving lens 114, the support member 111, and the optical fiber bundle 107 in one path, and in the other path, the light reception lens 116 and the support member. 112 and the optical fiber bundle 109 are input to the light detection unit 402.
Based on the measurement light detected by the light detection unit 402 via the two paths, the arithmetic control unit 120 determines the measurement object 102 such as the shape of the measurement object 102 as described in the first embodiment. The characteristic regarding the length of 102 is calculated.

  In the second embodiment, measurement light that enters the light detection unit 402 via the two paths can be measured when it enters the same light detection element of the light detection unit 402. Therefore, the measurement object 102 is scanned with a pattern of measurement light that does not enter the same light detection element, or the timing at which the measurement light enters the light detection unit 402 through the plurality of paths is shifted. That's fine.

  As described above, according to the optical measurement apparatus according to the embodiment of the present invention, the arithmetic control unit 120 controls the on / off of the optical switch unit 104 in a pattern for scanning the measurement object 102, and The measurement light is irradiated onto the measurement object 102 via the optical switch unit 104, the first optical fiber bundle 108, and the concave lens 115, and the measurement light reflected by the measurement object 102 passes through the light receiving lens 114 and the second optical fiber bundle 107. Is detected by the light detection unit 105 and detected by the light detection unit 106 via the light receiving lens 116 and the second optical fiber bundle 109, and the calculation control unit 120 detects the measurement light detected by the light detection units 105 and 106. Based on the above, a characteristic regarding the length of the three-dimensional shape or the like of the measurement object 102 is calculated.

  Therefore, it is possible to reduce the size of the measurement unit arranged on the measurement object 102 side with a simple configuration. Further, according to the second embodiment, since only one light detection unit is required, the configuration is further simplified and can be configured at low cost.

  The present invention can be applied to an optical measurement apparatus that requires downsizing of an optical measurement unit, such as an automobile transmission, and the like, such as a deep groove inner surface and a three-dimensional shape of an inner surface of a deep hole.

It is a perspective view which shows the basic composition of the optical measuring device which concerns on the 1st Embodiment of this invention. It is a block diagram of the optical fiber bundle used for the optical measuring device which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating the measurement operation | movement of the optical measuring device which concerns on the 1st Embodiment of this invention. It is a perspective view which shows the basic composition of the optical measuring device which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Optical measuring apparatus 102 ... Measurement object 103 ... 1st support member 104 ... Optical switch part 105 ... 1st light detection part 106 ... 2nd light detection part 108 ... First optical fiber bundle 107, 109 ... second optical fiber bundle 111-113 ... support member 115 ... concave lens 114, 116 ... light receiving lens 117-119 ... measuring light 120 ... Arithmetic control unit 130: light source 200 ... optical axis 201 ... optical fiber 202 ... light guide unit 203 ... covering unit 204 ... first end 205 ... second end 210 ... surface 210
211, 216, figure 212, optical fiber bundle 213, first bundle end 214, second bundle end 215, light detection section 401, support member 402, light Detection unit

Claims (7)

  The light output means for irradiating the measuring object with the measurement light via the first optical fiber bundle, the mutual positional relationship is known and disposed at a position unrelated to the position of the light output means, and the measurement object A plurality of light detection means for detecting the measurement light reflected by the second optical fiber bundle, and a characteristic relating to the length of the measurement object based on the measurement light detected by the plurality of light detection means. An optical measuring device comprising a calculating means for calculating.   The first optical fiber bundle and the second optical fiber bundle are configured such that the light output means side and the light detection means side have the same thickness as the measurement object side or thicker than the measurement object side, respectively. The optical measuring device according to claim 1.   3. The optical measurement apparatus according to claim 1, wherein the first optical fiber bundle and the second optical fiber bundle are formed by bundling a plurality of tapered optical fibers.   The light output means selectively outputs the measurement light from the light source to the light source that outputs the measurement light to the first optical fiber bundle side and each optical fiber that constitutes the first optical fiber bundle. 4. An optical switch means that is turned on or off to transmit or shield the light, and a control means that controls the optical switch means to be turned on or off. The optical measuring device described.   5. The optical measurement apparatus according to claim 1, wherein the light detection unit includes a light detection element corresponding to each optical fiber constituting the second optical fiber bundle. 6.   6. The optical measurement apparatus according to claim 1, wherein the plurality of light detection means are combined with one detection means.   7. The optical measurement apparatus according to claim 1, wherein each of the light detection means is configured by a CMOS photosensor array, a CCD, or a PSD.

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