Strain measurement device, strain measurement system, and group of strain measurement devices

Abstract

To provide a technique to measure strain with high accuracy without providing wiring on an object to be measured or providing a measuring device for each measurement point.SOLUTION: A strain measurement device includes a plurality of connection parts with an object to be measured, inclined parts and span extension parts between the connection parts, and a reflecting plate on the front surface of each of the inclined parts and the connection parts with the object to be measured, the inclined parts being connected to surroundings at different heights. A measurement system includes the strain measurement device.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a strain measuring device, a strain measuring system, and a laser beam emitting / receiving device. [Background technology]

[0002] Strain gauges are widely used as a technology for measuring strain. This technology involves attaching a strain gauge to the surface of the object to be measured and measuring the strain based on the change in electrical resistance caused by the strain of the object. While this technology allows for highly accurate measurements, it requires the preparation of wiring and bridge circuits for measuring the electrical resistance and the connection from the surface of the object to the circuit.

[0003] Digital image correlation has been developed as a technology for measuring strain without wiring the object being measured. This is a method for determining changes in a pattern on the surface of the object being measured from an image. This method is suitable for measuring strain distribution because it does not require wiring on the object being measured and can determine strain at multiple points. However, this method generally has lower measurement accuracy than the above-mentioned strain gauges. As a technique for optically measuring elongation, Patent Document 1 discloses a technique for measuring elongation using the tilt of a reflector caused by the elongation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 1-288701 Summary of the Invention [Problem to be solved by the invention]

[0005] When measuring strain, if it is necessary to provide wiring to the object to be measured or to prepare a bridge circuit or measuring device for each measurement point, the labor and equipment required for measurement will increase, and there may be limitations on the number of measurement points and measurement locations. On the other hand, currently available technologies that measure strain without providing wiring to the object to be measured have issues with high-precision strain measurement compared to technologies that provide wiring to the object to be measured. In order to solve the above-mentioned problems, the present invention provides a technique for measuring strain with high accuracy without providing wiring to an object to be measured or preparing a measuring device for each measurement point. [Means for solving the problem]

[0006] The above problem can be solved by a strain measuring device having multiple joints with the object to be measured, with inclined sections and span extension sections between the joints, with reflectors on the surfaces of each of the joints between the inclined sections and the object to be measured, and the inclined sections being connected to the surroundings at positions of different heights, and a measurement system using the device. Effect of the Invention

[0007] According to the present invention, since the strain can be measured by applying light to a measuring device attached to the object to be measured with a laser light transmitter / receiver and receiving the reflected light, there is no need to provide wiring to the object to be measured or to prepare a bridge circuit or measuring device for each measurement point. In addition, since minute strains in the object to be measured can be optically magnified and received, high-precision strain measurement is possible. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view, a top view, and a side view of a strain measuring device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing a state in which a strain measuring device according to a first embodiment of the present invention is attached to an object to be measured. [Diagram 3]FIG. 3 is an enlarged view showing deformation of the strain measuring device according to the first embodiment of the present invention when the strain measuring device is attached to a measurement object and strain occurs in the measurement object. [Figure 4] FIG. 4 is a diagram showing how reflected light is received using a strain measuring device and a laser light transmitter / receiver according to a first embodiment of the present invention. [Diagram 5] FIG. 5 is a diagram for explaining a procedure for determining the strain of a measurement object using a strain measuring device and a laser beam transmitter / receiver according to the first embodiment of the present invention. [Figure 6] FIG. 6 is a diagram for explaining a method for manufacturing a strain measuring device according to a first embodiment of the present invention. [Figure 7] FIG. 7 is a top view of a strain measuring device according to a second embodiment of the present invention. [Figure 8] FIG. 8 is a top view of a strain measuring device according to a third embodiment of the present invention. [Figure 9] FIG. 9 is a top view and a side view of a strain measuring device according to a fourth embodiment of the present invention. [Figure 10] FIG. 10 is a top view and a side view of a strain measuring device according to a fifth embodiment of the present invention. [Figure 11] FIG. 11 is a top view and a side view of a strain measuring device according to a sixth embodiment of the present invention. [Figure 12] FIG. 12 is a top view and a side view of a strain measuring device according to a seventh embodiment of the present invention. [Figure 13] FIG. 13 is a top view and a side view of a strain measuring device according to an eighth embodiment of the present invention. [Figure 14] FIG. 14 is a top view and a side view of a strain measuring device according to a ninth embodiment of the present invention, and an enlarged view of deformation of the strain measuring device when strain occurs in a measured object while the strain measuring device according to the ninth embodiment of the present invention is attached to the measured object. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment will be described with reference to the drawings.

[0010] First embodiment A first embodiment of the present invention will be described with reference to Figures 1 to 6. In this embodiment, the upper and lower sides will be specified based on Figure 2. 1A and 1B are a perspective view, a top view, and a side view of a strain measuring device according to a first embodiment of the present invention, where Fig. 1(a) is a perspective view, Fig. 1(b) is a top view, and Fig. 1(c) is a side view.

[0011] In this embodiment, the strain measuring device 1 has a length of about 1.4 mm, a width of about 0.2 mm, a height of about 0.3 mm, and is mainly made of silicon. Two reflectors 2 (2a, 2b) are provided on the upper surface of the strain measuring device 1. As shown in FIG. 1(c), joints 3 having joint surfaces with the object to be measured are arranged at both ends of the length of the strain measuring device 1, and a span extension section 4 and an inclined section 5 are provided inside the two joints 3. Note that when referring to the strain measuring device 1, particularly the strain measuring device 1 of the first embodiment, the reference symbol 1A will be used as appropriate.

[0012] The bottom surfaces of the span extension section 4 and the inclined section 5 of the strain measuring device 1A are provided above the bottom surface of the joint 3 with the measured object, the span extension section 4 and the inclined section 5 are connected at their respective bottom surfaces, and the inclined section 5 and the joint 3 with the measured object are connected at their respective top surfaces, and the heights of the connecting sections on both sides of the inclined section 5 from the joint surface are different. A reflector is provided on a surface different from the joint surface, and one of the two reflectors 2 is provided on the top surface of the joint 3 with the measured object, and the other is provided on the top surface of the inclined section 5. Note that the term "joint 3 with the measured object" may be omitted and the device may be referred to as "joint 3" as appropriate.

[0013] 2 is a diagram showing a state in which a strain measuring device 1 (1A) according to a first embodiment of the present invention is attached to a measurement object 21. An adhesive 22 is applied to the lower surfaces of joints 3 between the two measurement objects of the strain measuring device 1, and the device is attached to the measurement object 21. The adhesive hardens, and the strain measuring device 1 is fixed to the surface of the measurement object 21.

[0014] At this time, because the adhesive 22 is applied only to the underside of the joint 3 with the two measurement objects, and the undersides of the span extension portion 4 and the inclined portion 5 are provided above the underside of the joint 3 with the measurement object, the span extension portion 4 and the inclined portion 5 are not fixed to the measurement object 21. It is desirable for the adhesive 22 to be a material that has excellent adhesion to the underside of the joint 3 with the measurement object and to the surface of the measurement object 21, has high rigidity, and exhibits little creep deformation. In this embodiment, a room temperature curing epoxy adhesive was used for the adhesive 22.

[0015] FIG. 3 is an enlarged view showing the deformation of the strain measuring device 1 (1A) according to the first embodiment of the present invention when the strain is generated in the measured object 21 in a state where the strain measuring device 1 (1A) is attached to the measured object 21. Here, the distance between the joints 3 with the two measured objects is L. 0 , the width of the inclined portion 5 is L 1 The difference in height between the connecting parts on both sides of the inclined part 5 is defined as H. When a tensile load is applied to the measurement object 21 in the horizontal direction of the paper, a tensile strain ε is generated in the measurement object 21 in the horizontal direction.

[0016] At this time, the distance L between the joint 3 and the two objects to be measured 0 , L 0 ×ε. If this increased length is absorbed by the inclination of the inclined portion 5, a line 35 indicating the upper surface of the inclined portion 5 and a line 34 parallel to the upper surface of the measured object 21 form an angle θ (θ>0). If no tensile strain ε occurs, θ=0. Incidentally, if laser light is incident on the inclined portion 5 from a direction perpendicular to line 34, the angle of incidence (the angle between the normal 33 to the upper surface of the inclined portion 5 and the incident light 32) is also θ. The angle formed by the connection portions on both sides of the inclined portion 5 changes from θ to θ'.

[0017] As a result, the reflector 2 provided on the upper surface of the inclined portion 5 is inclined by θ with respect to the line 34. For this reason, in the strain measuring device 1 of this embodiment, the span expansion portion 4 is provided to 1 or H relative to L 0 It can be seen that θ can be increased by increasing the angle θ. The inclusion of the span expansion section 4 is a major feature of the present invention. On the other hand, the reflector 2 provided on the upper surface of the joint 3 with the measurement object is not tilted. As a result, the two reflectors 2 have different angles.

[0018] In the strain measuring device 1 of this embodiment, L 0 = 1.0 mm, L 1 The inclination angle of the inclined portion 5 under the conditions of A = 0.2 mm, H = 0.28 mm, and ε = 0.01 was calculated using the finite element method, and the inclination angle was found to be 1.8°. On the other hand, the reflector 2 provided on the upper surface of the joint 3 with the measured object is not inclined.

[0019] 4 is a diagram showing how reflected light is received using a strain measuring device and a laser beam transmitter / receiver according to a first embodiment of the present invention. Laser light emitted from the laser beam transmitter / receiver 41 is directed at the location on the surface of the measurement object 21 where the strain measuring device 1 is placed, and the reflected light 44 that hits the reflector 2 of the strain measuring device 1 is received by the laser beam transmitter / receiver 41. The strain measuring device 1 and the laser beam transmitter / receiver 41 constitute a strain measuring system.

[0020] When the measured object 21 is undeformed and no strain is generated, the inclined portion 5 of the strain measuring device 1 is not inclined, so that the reflected light 44 from the two reflectors 2 is reflected and received at the same interval as the incident light 43. On the other hand, when the measured object 21 is strained, the inclined portion 5 of the strain measuring device 1 is inclined, so that the reflected light 44 from the two reflectors 2 is received at an interval different from that of the incident light 43. By using the difference in the interval of this reflected light 44, the strain generated in the measured object 21 can be obtained.

[0021] In this embodiment, when a strain of 0.01 occurs in the measured object, the inclined portion 5 is inclined by 1.8°, so that the reflected light 44 from the reflector 2b on the inclined portion side is reflected at an angle of 3.6° with respect to the incident light 43. When this reflected light 44 is received by the laser light emitter / receiver 41 at a position 100 mm away, the receiving position moves by 6 mm or more compared to when the inclined portion 5 is not inclined. The L of the strain measuring device 1 when a strain of 0.01 occurs in the measured object 21 0 The change in L 0 × ε = 0.01 mm, and the signal can be received at a distance of 600 times the amount of displacement or more, enabling highly accurate strain measurement. Note that, as an example, the laser beam transmitter / receiver 41 receives the signal at a distance of 100 mm, but it is possible to receive the signal at a larger distance by changing the distance.

[0022] FIG. 5 is a diagram for explaining a procedure for determining the strain of a measurement object using a strain measuring device and a laser beam receiver according to a first embodiment of the present invention.

[0023] First, the laser beam transmitter / receiver 41 measures the interval between the reflected light from the two reflectors and the shape of the reflected light from the reflector 2a. The interval between the reflected light from the two reflectors is a value governed by the strain of the measurement object 21, but also varies depending on the distance and angle between the strain measuring device 1 and the laser beam transmitter / receiver 41. On the other hand, since the reflector 2a is disposed at a position where it is not tilted by the strain of the measurement object 21, the shape of this reflected light is not governed by the strain of the measurement object 21, but is governed by the distance and angle between the strain measuring device 1 and the laser beam transmitter / receiver 41.

[0024] Next, based on the measured shape of the reflected light from the reflector 2a, the laser beam transmitter / receiver 41 calculates the distance and angle between the strain measuring device 1 and the laser beam transmitter / receiver 41. Since the shape of the reflector 2a is known, if the size and shape of the reflected light from the reflector 2a can be measured, the distance and angle between the strain measuring device 1 and the laser beam transmitter / receiver 41 can be geometrically calculated.

[0025] Next, the laser beam transmitter / receiver 41 calculates the strain generated in the measurement object 21 based on the calculated distance and angle between the strain measuring device 1 and the laser beam transmitter / receiver 41 and the measured distance of the reflected light from the two reflectors. The strain generated in the measurement object 21 can be calculated by correcting the interval of the reflected light from the two reflectors, which is governed by the strain of the measurement object 21, using the distance and angle between the strain measuring device 1 and the laser beam transmitter / receiver 41.

[0026] Finally, the laser light emitting / receiving device 41 displays the calculated strain on a strain display device. The strain display device may be a computing device such as a personal computer, or a mobile terminal such as a smartphone.

[0027] In this embodiment, it is possible to obtain the value of the strain generated in the measured object 21 without the need for special wiring. Even when the number of strain measurements is large, it is possible to easily measure the strain by simply bringing the laser light emitter / receiver 41 close to the strain measuring device 1 attached to the measured object 21 and emitting and receiving light.

[0028] The laser beam transmitter / receiver 41 has a built-in computer. The processing shown in the flowchart of Fig. 5 is mainly performed by a program loaded into the computer. The processing contents of the flowchart are illustrated in more detail in the lower diagram of Fig. 5.

[0029] In the lower diagram of FIG. 5, line 51 is a line representing the surface from which the laser beam emitter / receiver 41 emits and receives laser beam. Line 52 is a line parallel to the upper surface of the measurement object 21, i.e., a line parallel to the upper surface of the strain measuring device 1. A user of the laser beam emitter / receiver 41 cannot hold the laser beam emitter / receiver 41 in a direction exactly perpendicular to line 52. Therefore, in many cases, line 51 and line 52 form an angle α. Now, due to the occurrence of strain ε, line 57 representing the upper surface of the reflector 2b forms an angle θ with line 52. Here, θ is the same as θ in FIG. 3.

[0030] At this time, the laser beam emitting / receiving device 41 emits laser beams 53a and 53b from points 58a and 58b toward the reflectors 2a and 2b, respectively. The laser beams 53a and 53b are perpendicular to the line 51. The laser beam emitting / receiving device 41 receives laser beams 54a and 54b from the reflectors 2a and 2b, respectively, at points 59a and 59b. The laser beams 53a and 54a form an angle "2×α". Naturally, a normal line 55a to the upper surface of the reflector 2a bisects the angle "2×α". Similarly, the laser beams 53b and 54b form an angle "2×β". A normal line 56 to the upper surface of the reflector 2b bisects the angle "2×β". And the line 55b is the normal line to the upper surface of the reflector 2b when the reflector 2b is not inclined (θ=0).

[0031] The laser beam transmitter / receiver 41 can calculate the size and shape (reflected beam shape) of the triangle surrounded by lines 51, 53a, and 54a. This means that the laser beam transmitter / receiver 41 can calculate the value of α. The laser beam transmitter / receiver 41 can also calculate the size and shape (reflected beam shape) of the triangle surrounded by lines 51, 53b, and 54b. This means that the laser beam transmitter / receiver 41 can calculate the value of β. Now, since "θ=β-α" is established, the laser beam transmitter / receiver 41 can calculate the value of θ.

[0032] The laser beam emitting / receiving device 41 calculates the actual length of the distortion "L 0 × ε” value can be calculated. 0 Since the value of is given, the laser beam transmitter / receiver 41 can eventually calculate the value of strain ε. Due to space limitations and for simplicity of explanation, only the surface including the long side of the strain measuring device 1 is shown two-dimensionally in the lower diagram of Fig. 5. The laser beam transmitter / receiver 41 is used in a three-dimensional space, and therefore, in reality, the laser beam transmitter / receiver 41 performs similar processing on surfaces other than those shown on the page of Fig. 5, and calculates the value of θ three-dimensionally based on the results.

[0033] FIG. 6 is a diagram for explaining a method for manufacturing a strain measuring device according to a first embodiment of the present invention.

[0034] First, a silicon wafer as shown in FIG. 6(a) is prepared. In this embodiment, a wafer with a thickness of 0.28 mm is used. Next, as shown in FIG. 6(b), grooves are provided from the top surface by dry etching. Next, as shown in FIG. 6(c), a metal thin film is provided on the top surface by sputtering. This metal thin film is a thin film that functions as a reflector 2, and is preferably a material with metallic luster. In this embodiment, aluminum is used. Next, as shown in FIG. 6(d), a mask is used to leave a part of the previously provided metal thin film and remove the other part. The remaining part becomes the reflector 2. Next, the back surface is processed as shown in FIG. 6(e). Steps and grooves are provided on the bottom surface by two-stage etching. Finally, the four sides are cut by dicing to complete the strain measuring device 1 (1A).

[0035] In this manufacturing method, a fine device structure can be realized by using a semiconductor manufacturing process. In addition, since a plurality of strain measuring devices 1 can be simultaneously formed and individualized on one wafer, manufacturing costs can be reduced.

[0036] In the strain measuring device 1 of this embodiment, the distance L 0 or H relative to L 0 By increasing L, the inclination of the inclined portion 5 with respect to the strain of the measurement object 21 can be increased, so that the strain can be obtained with high accuracy. 0 is the average strain occurring at the dimension L 0 In this embodiment, the strain measuring device 1 is manufactured from a silicon wafer using a semiconductor manufacturing process, and the distance L 1 or H relative to L 0 Even if you increase L 0 This is a dimension equivalent to or smaller than the gauge length of conventional strain gauges, and is a major feature of the present invention.

[0037] In this embodiment, silicon is used as the main material of the strain measuring device 1. When strain measurement is performed in a temperature-changing environment, if there is a difference in the linear expansion coefficient between the strain measuring device 1 and the measured object 21, the inclined portion 5 will incline due to the difference in thermal deformation. To prevent a decrease in the measurement accuracy of the strain measurement due to the inclination of the inclined portion 5 caused by this temperature change, it is effective to correct the deformation due to the temperature change, or to reduce the difference in the linear expansion coefficient between the main material of the strain measuring device 1 and the measured object 21, or to take both of these measures.

[0038] In the former case, the temperature is also measured during strain measurement, and the inclination of the inclined portion 5 determined from the temperature is removed from the strain measurement result. In the latter case, the same material as the measured object 21 or a material with a similar linear expansion coefficient is used as the main material of the strain measuring device 1. For example, when performing strain measurement with an accuracy of 100 ppm or less in an environment with a temperature change of 100°C, it is desirable that the difference in linear expansion coefficient between the main material of the strain measuring device 1 and the measured object 21 is 1 ppm / °C or less. In addition, by preparing a plurality of strain measuring devices 1 whose main materials are materials with different linear expansion coefficients in advance (a group of strain measuring devices) and selecting the main material of the strain measuring device 1 according to the linear expansion coefficient of the measured object, the difference in linear expansion coefficient between the main material of the strain measuring device 1 and the measured object 21 can be reduced.

[0039] In this embodiment, the strain measuring device 1 was manufactured by applying a manufacturing process for semiconductor devices because silicon was used as the main material of the strain measuring device 1. If another material is used as the main material of the strain measuring device 1, the strain measuring device 1 can be manufactured by performing mechanical processing instead of dry etching.

[0040] Second Example 7 is a top view of a strain measuring device 1B according to a second embodiment of the present invention. The difference from the first embodiment is that the strain measuring device of the first embodiment measures strain in one axis direction, whereas the strain measuring device of this embodiment can measure strain in two axis directions.

[0041] As shown in FIG. 7, the strain measuring device 1B of the second embodiment is L-shaped and has joints 3 with the object to be measured at three locations: both ends (one end (first end) and the other end (second end)) and the intersection. A span extension section 4 and a slope section 5 are provided between the joint 3 at one end and the joint 3 at the intersection, ensuring the distance between the joints 3. Similarly, a span extension section 4 and a slope section 5 are provided between the joint 3 at the other end and the joint 3 at the intersection, ensuring the distance between the joints 3. In addition, the strain measuring device 1B of the present embodiment has reflectors 2 at a total of three locations: the top surface of the joint 3 with the object to be measured at the intersection and the top surfaces of the two slope sections 5.

[0042] The strain measuring device 1B of the second embodiment is attached to the surface of the object to be measured, and the strain is measured using a laser light transmitter / receiver in the same manner as in the case of the strain measuring device 1A of the first embodiment. When measuring this strain, the strain measuring device 1B of the second embodiment can also determine the strain in the vertical direction of the paper from the interval between the reflected light from the reflectors 2a and 2b, and the strain in the horizontal direction of the paper from the interval between the reflected light from the reflectors 2a and 2b'. In this way, the second embodiment is characterized in that it is possible to determine strain in two directions by attaching one strain measuring device 1B to the object to be measured.

[0043] Third Example 8 is a top view of a strain measuring device 1C according to the third embodiment of the present invention. The difference from the first and second embodiments is that the strain measuring device of the first embodiment measures strain in one axis direction and the strain measuring device of the second embodiment measures strain in two axis directions, whereas the strain measuring device of this embodiment can measure strain in three axis directions.

[0044] 8, the strain measuring device 1C of the third embodiment has a shape extending in three directions from the intersection at the lower left, and has joints 3 with the measurement object at four locations: three ends (first end, second end, and third end) and the intersection, and has span extension sections 4 and inclined sections 5 between each of the joints 3 with the measurement object at the end and the intersection, as in the second embodiment. Furthermore, the strain measuring device 1C of this embodiment has reflectors 2 at a total of four locations: the top surface of the joint 3 with the measurement object at the intersection and the top surfaces of the three inclined sections 5.

[0045] When the strain measuring device 1C of this embodiment is attached to the surface of the object to be measured and the strain is measured using a laser light transmitter / receiver as in the first and second embodiments, the strain in the vertical direction of the paper surface can be obtained from the interval between the reflected light from the reflectors 2a and 2b. Furthermore, the strain in the horizontal direction of the paper surface can be obtained from the interval between the reflected light from the reflectors 2a and 2b', and the strain in the shear direction can be obtained from the interval between the reflected light from the reflectors 2a and 2b''. This makes it possible to obtain all components of strain occurring on the surface of the object to be measured 21. In this way, the present embodiment is characterized in that the strain in three directions can be obtained by attaching one strain measuring device to the object to be measured.

[0046] <Fourth embodiment> 9 is a top view and a side view of a strain measuring device 1D according to a fourth embodiment of the present invention. The difference from the strain measuring device 1A of the first embodiment is that the strain measuring device ID of the fourth embodiment has a distance / angle measurement marker 91 around the reflector 2 provided on the upper surface of the joint 3 with the measurement object.

[0047] In the first embodiment, the laser beam transmitter / receiver 41 measures the shape of the reflected light from the reflector 2a to calculate the distance and angle between the strain measuring device 1A and the laser beam transmitter / receiver 41. In contrast to this, in the fourth embodiment, the shape of the reflected light from the distance / angle measuring marker 91 is measured to calculate the distance and angle between the strain measuring device 1D and the laser beam transmitter / receiver 41. In the first embodiment, the strain measurement is calculated using the reflected light from the reflector 2a, and the distance and angle between the strain measuring device 1A and the laser beam transmitter / receiver 41 are also calculated using the reflected light from the reflector 2a. However, in the fourth embodiment, the reflected light from the reflector 2a is used for the strain measurement, while the reflected light from the distance / angle measuring marker 91 is used for the distance and angle measurement between the strain measuring device 1D and the laser beam transmitter / receiver 41. Therefore, shapes and materials suitable for the respective functions of the reflector 2a and the distance / angle measuring marker 91 can be used. Furthermore, by providing a plurality of distance / angle measuring markers 91, the distance and angle between the strain measuring device 1D and the laser beam transmitter / receiver 41 can be measured with higher accuracy.

[0048] Fifth Example 10 is a top view and a side view of a strain measuring device 1E according to the fifth embodiment of the present invention. The difference from the first embodiment is that, whereas in the first embodiment, the joint 3 with the object to be measured, the span extension 4, and the inclined portion 5 are made of a single piece of silicon, the strain measuring device 1E of the fifth embodiment has thin films 101a, 101b, and 101c on the top and back surfaces, and the joint 3 with the object to be measured, the span extension 4, and the inclined portion 5 are made of a plurality of materials.

[0049] In the fifth embodiment, by using a plurality of materials, it is possible to use a material suitable for each part. Materials 101a and 101b with high bending strength can be used as the material for the part where bending deformation occurs when the inclined portion 5 is inclined, and material 101c with good adhesiveness can be used as the material for bonding to the measured object 21. These thin films 101a, 101b, and 101c can also be formed by sputtering or deposition in the semiconductor process, as in the manufacturing method of the first embodiment. However, the number of manufacturing processes is increased compared to the first embodiment. Based on these characteristics, the structure of the strain measurement device can be selected.

[0050] Sixth embodiment 11 is a top view and a side view of a strain measuring device 1F according to the sixth embodiment of the present invention. The difference from the first embodiment is that the groove width on both sides of the inclined portion 5 in the first embodiment is uniform, whereas the strain measuring device 1F of the sixth embodiment has a taper.

[0051] In the first embodiment, the grooves were formed by dry etching, so the groove width was uniform. In the sixth embodiment, the grooves are formed by wet etching, so that tapered grooves are formed. Even when the grooves are tapered, the inclined portion 5 is inclined due to the strain of the measurement object 21, so strain measurement is possible. However, the overall length of the strain measuring device 1 increases due to the tapered grooves. Based on these characteristics, a manufacturing method can be selected.

[0052] Seventh embodiment 12 is a top view and a side view of a strain measuring device 1G according to the seventh embodiment of the present invention. The difference from the first embodiment is that the grooves on the side surface of the inclined portion 5 are formed from the top or bottom surface in the first embodiment, whereas the grooves are formed from the top and bottom surfaces in the strain measuring device 1G of the seventh embodiment.

[0053] In the seventh embodiment, the groove on the side surface of the inclined portion 5 is formed from the top and bottom surfaces, so that the height difference H between the connection parts on both sides of the inclined portion 5 can be set independently of the height of the strain measuring device. As a result, the inclination angle of the inclined portion 5 caused by the strain of the measurement object 21 can be controlled, thereby improving the measurement accuracy of the strain measurement.

[0054] Eighth embodiment 13 is a top view and a side view of a strain measuring device 1H according to the eighth embodiment of the present invention. The difference from the first embodiment is that, whereas in the first embodiment, the reflector 2 on the joint side with the object to be measured is provided on the top surface of the joint 3 with the object to be measured beyond the span extension part, in the strain measuring device 1H of the eighth embodiment, it is provided on the top surface of the joint 3 with the object to be measured on the side closer to the inclined part 5.

[0055] Similar to the joint 3 with the object to be measured at the end of the span extension section, the joint 3 with the object to be measured closer to the inclined section 5 also does not tilt due to the strain of the object to be measured 21. Therefore, no matter which side the reflector 2 is provided on, the interval between the reflected light from the two reflectors changes due to the strain of the object to be measured 21, making it possible to measure strain.

[0056] Ninth embodiment 14 is a side view of a strain measuring device 1I according to a ninth embodiment of the present invention, and an enlarged view showing deformation of the strain measuring device when strain occurs in a measured object while the strain measuring device according to the ninth embodiment of the present invention is attached to the measured object. The difference from the first embodiment is that the width of the joint 3 with the measured object at two places is the same in the first embodiment, whereas the width of the joint 3 with the measured object at the end of the span expansion part 4 in the strain measuring device 1I of the ninth embodiment is larger.

[0057] When the width of the joint 3 with the object to be measured beyond the span extension portion 4 is small, the joint has a small rigidity, and the joint may be slightly tilted due to the strain of the object to be measured 21, affecting the strain measurement. In this embodiment, the inclination of the joint 3 with the object to be measured beyond the span extension portion 4 due to the strain of the object to be measured 21 can be reduced by increasing the width and rigidity of the joint 3 with the object to be measured beyond the span extension portion 4. Compared to the joint 3 with the object to be measured beyond the span extension portion 4, the rigidity of the joint 3 with the object to be measured closer to the inclination portion 5 has a smaller effect on the inclination angle of the reflector 2, so it is effective to increase the width of the joint 3 with the object to be measured beyond the span extension portion 4 than the joint 3 with the object to be measured closer to the inclination portion 5.

[0058] Although the present invention has been specifically described above based on the embodiments, it goes without saying that the present invention is not limited to the above embodiments and can be modified in various ways without departing from the spirit of the present invention. [Explanation of symbols]

[0059] 1 Strain measurement device 2 Reflector 2a Reflector on the joint side with the object to be measured 2b Reflector on the inclined side 3. Joint with the object to be measured 4 Span Extension 5 Slope 21 Measurement subject 22 Adhesive 31 Load 41 Laser light transmitter / receiver 42 Laser light 43 Incident light 44 Reflected light 61 Silicon Wafer 62 Dry etching groove 63 Sputtered film 91 Distance and angle measurement markers 101a, 101b, 101c thin film

Claims

1. It has multiple joints with the object to be measured, A sloped portion and a span extension portion are provided between the joints, a reflector is provided on a surface of the inclined portion and on a surface of a joint with the measurement object, The inclined portion is connected to the periphery at different heights; A strain measurement device comprising:

2. The strain measuring device according to claim 1, The structure is an L-shape in which two perpendicular structures intersect at an end, a joint portion for connecting the end portion of the two structures to the measurement object at the intersection point; The two structures each include an inclined portion and a span extension portion between the end portion and a joint portion between the end portion and the measurement object at the intersection, a reflector is provided on a surface of the inclined portion and on a surface of a joint with the measurement object, The inclined portion is connected to the periphery at different heights; A strain measurement device comprising:

3. The strain measuring device according to claim 1, The three structures have an intersection at the end, The three structures have ends and an intersection at which they are joined to a measurement object, The three structures each include an inclined portion and a span extension portion between the end portion and a joint portion between the end portion and the measurement object at the intersection, a reflector is provided on a surface of the inclined portion and on a surface of a joint with the measurement object, The inclined portion is connected to the periphery at different heights; A strain measurement device comprising:

4. The strain measuring device according to claim 1, providing a marker on an upper surface of the strain measuring device for use in calculating a distance and an angle between the strain measuring device and a laser beam transmitter / receiver; A strain measurement device comprising:

5. The strain measuring device according to claim 1, The strain measuring device has a thin film on the top surface, the bottom surface, or both surfaces; A strain measurement device comprising:

6. The strain measuring device according to claim 1, The groove on the side surface of the inclined portion is tapered. A strain measurement device comprising:

7. The strain measuring device according to claim 1, one or both of the grooves on both side surfaces of the inclined portion are formed by grooves provided from the upper and lower surfaces; A strain measurement device comprising:

8. The strain measuring device according to claim 1, a reflector is provided on the surface of the inclined portion, and a reflector is provided on an upper surface of a joint portion with the object to be measured that is closer to the inclined portion; A strain measurement device comprising:

9. In the strain measuring device according to any one of claims 1 to 8, The difference between the linear expansion coefficient of the main material of the strain measuring device and the linear expansion coefficient of the measured object is 1 ppm / °C or less; A strain measurement device comprising:

10. In the group of strain measuring devices according to any one of claims 1 to 8, Each of the measurement devices in the group comprises: The material is made of a material having a different linear expansion coefficient corresponding to the linear expansion coefficient of the measurement object. A group of strain measurement devices characterized by:

11. A strain measuring device comprising the strain measuring device according to any one of claims 1 to 9 and a laser beam transmitter / receiver, The light emitted from the laser light transmitter / receiver is reflected by a reflector provided in the strain measuring device and is received again by the laser light transmitter / receiver; Calculating and displaying the strain based on the interval of the received reflected light; A strain measurement system characterized by:

12. The strain measurement system according to claim 11, Calculating a distance and an angle between the strain measuring device and the laser beam transmitter / receiver based on information of the reflected light received by the laser beam transmitter / receiver; Calculating and displaying strain based on the calculated information on the distance and angle between the strain measuring device and the laser light transmitter / receiver and the interval between the received reflected lights; A strain measurement system characterized by:

13. The strain measuring device according to claim 1, a width of a joint portion between the span extension portion and the object to be measured is larger than a width of a joint portion between the span extension portion and the object to be measured on a side closer to the inclined portion; A strain measurement device comprising:

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