Shape measuring device

Abstract

A shape measuring apparatus (100) has a first light projecting section (10) that irradiates a first line light (L1) and a second line light (L2), a first imaging section (20) that has a first imaging field of view (F1), images an object passing through a first measurement region (Z1) that is a region where a first plane (V1) through which the first line light (L1) passes intersects the first imaging field of view (F1), and images an object passing through a second measurement region (Z2) that is a region where a second plane (V2) through which the second line light (L2) passes intersects the first imaging field of view (F1), and a measurement section (50) that measures a shape of the object based on a first image (B11) that is an image of a portion of the object passing through the first measurement region (Z1) that is irradiated with the first line light (L1), and a second image (B22, B23) that is an image of a portion of the object passing through the second measurement region (Z2) that is irradiated with the second line light (L2).

Description

Technical Field

[0001] This disclosure relates to a shape measuring device. Background Technology

[0002] As methods for determining the three-dimensional shape of an object, both contact and non-contact measurement methods are known. As a non-contact method, the optical cut-off method is becoming increasingly popular. In the optical cut-off method, for example, a beam of light is shone from a projection unit toward the object, and an image of the beam of light projected onto the object is captured by an imaging unit. In this case, the direction of the imaging field of view of the imaging unit is different from the direction of the beam of light. In a shape measuring apparatus employing the optical cut-off method, the three-dimensional shape of the object is determined based on images acquired sequentially by moving the object relative to the position of the optical system comprising the projection unit and the imaging unit.

[0003] Here, the resolution of the shape measuring device is obtained by dividing the field of view of the imaging unit by the number of pixels. Therefore, when the measurement range in the height direction of the object is expanded, the resolution decreases. To prevent the decrease in resolution, shape measuring devices with two imaging units are known. For example, see Patent Document 1.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2015-114235 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] However, the structure in Patent Document 1 includes two imaging units, which results in high cost. Furthermore, the structure in Patent Document 1 increases the amount of image data required for measurement and processing, thus increasing the computational load. Additionally, the structure in Patent Document 1 requires synchronization control to synchronize the images acquired by the two imaging units, which complicates the device.

[0009] The purpose of this disclosure is to provide a low-cost, computationally-intensive, and simple shape measurement device.

[0010] means for solving problems

[0011] The shape measuring device of this disclosure is characterized by comprising: a first projection unit that irradiates a first linear light and a second linear light; a first imaging unit having a first imaging field of view that images an object passing through a first measuring region and an object passing through a second measuring region, wherein the first measuring region is a region where a first plane through which the first linear light passes intersects with the first imaging field of view, and the second measuring region is a region where a second plane through which the second linear light passes intersects with the first imaging field of view, the second measuring region being different from the first measuring region and disposed at a position closer to the first projection unit than the first measuring region; and a measuring unit that measures the shape of the object based on a first image and a second image, wherein the first image is an image of the portion of the object in the first measuring region illuminated by the first linear light, and the second image is an image of the portion of the object in the second measuring region illuminated by the second linear light.

[0012] The effects of the invention

[0013] According to this disclosure, a low-cost, computationally-intensive, and simple shape measurement device can be provided. Attached Figure Description

[0014] Figure 1 This is a perspective view showing the outline structure of the shape measuring device of Embodiment 1 and the first object.

[0015] Figure 2 It is observed along the X-axis. Figure 1 The diagram shows the shape measuring device and the first object.

[0016] Figure 3 This is a diagram showing the shape measuring device and the first object observed along the X-axis at the start of the measurement.

[0017] Figure 4 (A) and (B) are shown as the first object passes through the first measurement area by Figures 1 to 3 The diagram shows an example of the transformation of an image captured by the camera unit.

[0018] Figure 5 (A) is a diagram showing the shape measuring device of Embodiment 1 and the second object observed along the X-axis at the start of the measurement. Figure 5 (B) is a diagram showing the shape measuring device of Embodiment 1 and the second object passing through the second measuring area after the measurement has started, viewed along the X-axis.

[0019] Figure 6 (A) to (D) are shown as the second object passes through the second measurement area by Figure 5The figure shows an example of the transformation of the image captured by the camera unit, as shown in (A) and (B).

[0020] Figure 7 This is a diagram showing the shape measuring device and the object of Embodiment 2 viewed along the X-axis.

[0021] Figure 8 This is a diagram showing the shape measuring device and the object of Embodiment 3 viewed along the X-axis.

[0022] Figure 9 This is a diagram showing the shape measuring device and the object of Embodiment 4 viewed along the X-axis. Detailed Implementation

[0023] Hereinafter, the shape measuring apparatus according to embodiments of the present disclosure will be described with reference to the accompanying drawings. The following embodiments are merely examples, and embodiments can be appropriately combined and modified.

[0024] The shape measuring apparatus of this embodiment measures the three-dimensional shape of the object to be measured (hereinafter also referred to as "the object") using an optical sectioning method. For ease of explanation, the coordinate axes of the XYZ orthogonal coordinate system are shown in the figure. The X-axis and Y-axis are coordinate axes parallel to the reference plane S on which the object is placed. The Y-axis is a coordinate axis parallel to the scanning direction of the shape measuring apparatus. The Z-axis is a coordinate axis orthogonal to the X-axis and Y-axis, and represents the direction of the height of the object from the reference plane S.

[0025] Implementation Method 1

[0026] Figure 1 This is a perspective view showing the outline structure of the shape measuring device 100 of Embodiment 1 and the first object 110. Figure 2 It is observed along the X-axis. Figure 1 The figure shows the shape measuring device 100 and the first object 110. The first object 110 (hereinafter also referred to as "object 110") is an example of an object to be measured.

[0027] The shape measuring device 100 includes a light projection unit 10 (hereinafter also referred to as "first light projection unit 10"), an imaging unit 20 (hereinafter also referred to as "first imaging unit 20"), and a measuring unit 50.

[0028] The projection unit 10 illuminates a first linear light L1 and a second linear light L2, both of which are linear beams. Thus, the projection unit 10 illuminates two linear beams. The first linear light L1 and the second linear light L2 are beams that extend along the X-axis. The first linear light L1 and the second linear light L2 are projected onto the surface of the first object 110. The image (pattern) of each of the first linear light L1 and the second linear light L2 projected onto the surface of the first object 110 is a linear shape extending along the X-axis. Alternatively, the projection unit 10 may illuminate three or more linear beams.

[0029] The second light beam L2 is illuminated from a position separated from the first light beam L1 in a predetermined scanning direction, i.e., the Y-axis direction. The second light beam L2 is parallel to the first light beam L1 in the X-axis direction. Alternatively, it is not limited to the X-axis direction; the second light beam L2 can be parallel to the first light beam L1 in a predetermined direction. Furthermore, the projection section illuminating the first light beam L1 and the projection section illuminating the second light beam L2 can be separately provided. Additionally, the wavelength of the first light beam L1 can be different from the wavelength of the second light beam L2, and the power of the first light beam L1 can also be different from the power of the second light beam L2.

[0030] like Figure 2 As shown, the projection section 10 includes, for example, a point light source 10a, a collimating lens 10b, and a cylindrical lens 10c. The collimating lens 10b collimates the light emitted from the point light source 10a. The cylindrical lens 10c makes the pattern of the light collimated by the collimating lens 10b linear. Thus, a first linear light L1 and a second linear light L2 are formed.

[0031] The imaging unit 20 is, for example, a camera with a CMOS (Complementary Metal Oxide Semiconductor) image sensor. The imaging unit 20 has an imaging field of view F1 (hereinafter also referred to as "first imaging field of view F1"). The direction of the imaging field of view F1 is different from the illumination direction of the first line light L1 and the second line light L2 of the projection unit 10.

[0032] exist Figure 1 and 2In the example shown, the imaging unit 20 images the first object 110 passing through the first measurement region Z1. Here, the first measurement region Z1 is the area where the first ray light L1 intersects with the field of view F1. Specifically, the first measurement region Z1 is the area where the first plane V1, through which the first ray light L1 passes, intersects with the field of view F1. The first plane V1 is an imaginary XZ plane. The height H1 of the first object 110 from the reference plane S is included in the first measurement region Z1. In addition, the first ray light L1 and the second ray light L2 may sometimes be non-parallel to the XZ plane depending on the angle of incidence, but are illuminated along the XZ plane. Therefore, the first plane V1 and the second plane V2 through which the second ray light L2 passes, described later, are respectively referred to as the "imaginary XZ plane".

[0033] The imaging unit 20 acquires an image of the portion of the first object 110 illuminated by the first ray light L1 passing through the first measurement area Z1. The portion of the first object 110 illuminated by the first ray light L1 is, for example, the surface of the first object 110 facing the +Z axis direction (hereinafter also referred to as the "upper surface") 111.

[0034] In addition, as will be discussed later Figure 5 As shown in (A) and (B), the imaging unit 20 images a second object 120 passing through a second measurement region Z2, which is different from the first measurement region Z1. Here, the second measurement region Z2 is the region where the second ray L2 intersects with the field of view F1. Specifically, the second measurement region Z2 is the region where the second plane V2, through which the second ray L2 passes, intersects with the field of view F1. The second plane V2 is an imaginary XZ plane.

[0035] The second measurement region Z2 is positioned closer to the projection section 10 (i.e., the +Z-axis side) than the first measurement region Z1. In Embodiment 1, the second measurement region Z2 is arranged adjacent to the first measurement region Z1 in the Z-axis direction. Furthermore, the second measurement region Z2 does not overlap with the first measurement region Z1 in the Z-axis direction. Additionally, as long as a large portion of the second measurement region Z2 does not overlap with the first measurement region Z1, a portion of the second measurement region Z2 may overlap with the first measurement region Z1. That is, the second measurement region Z2 only needs to include an area that does not overlap with the first measurement region Z1.

[0036] Here, in embodiment 1, the angle of incidence of the second line light L2 relative to the normal W of the reference plane S (e.g., Figure 2The angle θ shown is different from the incident angle of the first ray L1. Therefore, the second measurement region Z2 can be made different from the first measurement region Z1. In Embodiment 1, the first ray L1 is incident on the object along the normal W. Therefore, the incident angle of the first ray L1 on the object is 0 degrees. In contrast, the incident angle of the second ray L2 on the object is an angle θ greater than 0 degrees. Alternatively, the incident angle of the second ray L2 can be the same as the incident angle of the first ray L1. That is, the incident angle of the second ray L2, or the second incident angle, can be greater than or equal to the incident angle of the first ray L1, or the first incident angle.

[0037] Furthermore, by adjusting the position of the imaging unit 20 and the optical axis angle of the imaging unit 20, it is also possible to make the second measurement region Z2 a region different from the first measurement region Z1.

[0038] Furthermore, in Embodiment 1, the length A2 of the second measurement region Z2 is the same as the length A1 of the first measurement region Z1 in the Z-axis direction. Additionally, as described later... Figure 7 As shown, in the Z-axis direction, the length A1 of the first measurement region Z1 can also be shorter than the length A2 of the second measurement region Z2. That is, the length A1 of the first measurement region Z1 can be less than or equal to the length A2 of the second measurement region Z2.

[0039] The shape measuring device 100 also includes a moving part (not shown) that moves (transports) the object in the scanning direction (Y-axis direction in Embodiment 1). Furthermore, this moving part can also move the optical system 15, which includes the projection unit 10 and the imaging unit 20, in the scanning direction while the object is stationary. That is, in Embodiment 1, the optical system 15 and the object move relative to each other in the Y-axis direction. Therefore, the imaging unit 20 can sequentially capture images containing the image of the line light projected onto the object.

[0040] The measuring unit 50 measures the shape of the object based on the image acquired by the imaging unit 20. The measuring unit 50 is, for example, a CPU (Central Processing Unit) equipped with memory. Based on the image acquired by the imaging unit 20, the measuring unit 50 calculates data representing the height information of the object. For example, if the object is a first object 110 with a height H1, the measuring unit 50 calculates the height H1 of the first object 110 based on an image of the portion of the first object 110 that is illuminated by the first ray light L1 passing through the first measuring region Z1.

[0041] When the measuring unit 50 calculates the height of the object, it needs to determine whether the image of the line light projected onto the object is the image of the first line light L1 or the image of the second line light L2. The determination method of the measuring unit 50 will be explained below. First, using... Figure 3, Figure 4 (A) and (B) will be explained with respect to the images captured by the imaging unit 20 when the first object 110 passes through the first measurement area Z1.

[0042] Figure 3 This diagram shows the shape measuring device 100 and the first object 110 viewed along the X-axis at the start of the measurement. At the start of the measurement of the first object 110, a first linear light L1 is irradiated onto the end of the upper surface 111 of the first object 110 on the -Y-axis side. In the following description, the start of the measurement will be set to time t = 0. After the measurement begins, the first object 110 is moved along the -Y-axis, and the imaging unit 20 acquires an image containing the image of the first linear light L1 projected onto the upper surface 111 of the first object 110.

[0043] Figure 4 (A) and (B) illustrate the shape of the first object 110 being measured by the shape measuring device 100. Figures 1 to 3 This diagram illustrates an example of the transformation of images captured by the imaging unit 20. To make... Figure 4 (A) and (B) and the following. Figure 6 The illustration of the images shown in (A) to (D) becomes easier, in which the Y1 axis, representing the height of the object, and the X1 axis, which is orthogonal to the Y1 axis, are used.

[0044] Figure 4 (A) is a schematic diagram showing an example of image B10 acquired at time t < 0. At time t < 0, the first ray light L1 is not illuminated by the first object 110 but is illuminated by the reference plane S. Therefore, in image B10, the image P10 of the first ray light L1 projected onto the reference plane S is projected. At time t < 0, the second ray light L2 is also illuminated by the reference plane S, but the image of the second ray light L2 is not included in the field of view F1. Therefore, in image B10, the image of the second ray light L2 is not projected.

[0045] Figure 4 (B) is a schematic diagram showing an example of image B11 acquired at time t ≥ 0. At time t ≥ 0, the first ray L1 is illuminated onto the reference plane S and the upper surface 111 of the first object 110. Therefore, in image B11, in addition to image P10, the image P11 of the first ray L1 projected onto the upper surface 111 is also reflected. The position of image P11 in the Y1 axis direction in image B11 corresponds to the height H1 of the first object 110. The distance between image P10 and image P11 in the Y1 axis direction is the same as the height H1.

[0046] At time t≥0, although the second line light L2 is also illuminated on the reference plane S and the first object 110, the image of the second line light L2 is not included in the field of view F1. Therefore, the image of the second line light L2 is not reflected in image B11.

[0047] Next, use Figure 5 (A) and (B) and Figure 6 (A) to (D) will be described with respect to the images obtained by the imaging unit 20 when the second object 120, which is higher than the first object 110, passes through the first measurement area Z1 and the second measurement area Z2. Figure 5 (A) is a diagram showing the shape measuring device 100 and the second object 120 of Embodiment 1 viewed along the X-axis at the start of the measurement (i.e., time t = 0). The second object 120 also moves in the -Y-axis direction, just like the first object 110.

[0048] like Figure 5 As shown in (A), the height H2 of the second object 120 from the reference plane S is included in the first measurement area Z1 and the second measurement area Z2. When the imaging unit 20 moves the second object 120 in the -Y-axis direction, it acquires an image of the portion of the second object 120 illuminated by the first linear light L1 and the second linear light L2. The portion of the second object 120 illuminated by the first linear light L1 is the upper surface 121 of the second object 120. Furthermore, the portion of the second object 120 illuminated by the second linear light L2 is the upper surface 121 and the side surface 122 of the second object 120. At the start of the measurement of the second object 120, the first linear light L1 is illuminated towards the end of the upper surface 121 on the -Y-axis side of the second object 120.

[0049] Figure 5 (B) is a diagram showing the shape measuring device 100 of Embodiment 1 and the second object 120 passing through the second measuring region Z2, viewed along the X-axis after the measurement has begun. Figure 5 In (B), a second beam of light L2 is irradiated onto the side 122 of the second object 120. Hereinafter, the moment when the second beam of light L2 is irradiated onto the side 122 of the second object 120 will be defined as t1. As time passes from t1, the portion of the second object 120 irradiated with the second beam of light L2 changes from the side 122 to the upper surface 121. Furthermore, as long as the incident angles of the first beam of light L1 and the second beam of light L2, the position of the imaging unit 20, and the moving speed of the second object 120 remain unchanged, if the height H2 of the second object 120 is contained within the second measurement area Z2, then t1 is fixed regardless of the magnitude of the height H2.

[0050] Figure 6(A) to (D) show the shape of the second object 120 being measured by the shape measuring device 100. Figure 5 The figure shows an example of the transformation of the image captured by the camera unit 20, as shown in (A) and (B). Figure 6 (A) is a schematic diagram showing an example of image B20 acquired at time t < 0. At time t < 0, the first ray light L1 is not illuminated by the second object 120, but is illuminated by the reference plane S. Therefore, in image B20, the image P10 of the first ray light L1 projected onto the reference plane S is projected. At time t < 0, although the second ray light L2 is also illuminated by the reference plane S, the image of the second ray light L2 is not included in the field of view F1. Therefore, the image of the second ray light L2 is not projected in image B20.

[0051] Figure 6 (B) is a schematic diagram showing an example of image B21 acquired after the start of the measurement of the second object 120 and before the elapsed time t1. When 0 ≤ t < t1, the first ray L1 is illuminated by the reference plane S and the upper surface 121. The image of the first ray L1 projected onto the upper surface 121 is not included in the field of view F1. Therefore, in image B21, the image of the first ray L1 projected onto the upper surface 121 of the second object 120 is not shown, but the image P10 of the first ray L1 projected onto the reference plane S is shown.

[0052] Figure 6 (C) is a schematic diagram illustrating an example of image B22 taken at time t = t1. As described above... Figure 5 As shown in (B), at time t = t1, the first ray L1 is illuminated by the reference plane S and the upper surface 121, and the second ray L2 is illuminated by the side surface 122 of the second object 120. At time t = t1, the image of the first ray L1 projected onto the upper surface 121 is not included in the field of view F1. Therefore, in image B22, the image P10 of the first ray L1 projected onto the reference plane S and the image P21 of the second ray L2 projected onto the side surface 122 are projected. Images P10 and P21 are projected at the ends of the -Y1 axis side of image B22.

[0053] Figure 6(D) is a schematic diagram showing an example of image B23 acquired after time t1. At time t > t1, the first ray L1 is illuminated by the reference plane S and the upper surface 121. Furthermore, at time t > t1, after the second ray L2 has illuminated the side surface 122 for a certain period of time, it is illuminated by the upper surface 121. At time t > t1, the image of the first ray L1 projected onto the upper surface 121 is not included in the field of view F1. Therefore, in image B23, in addition to the image P10 of the first ray L1 projected onto the reference plane S, the image P22 of the second ray L2 projected onto the upper surface 121 or the side surface 122 is also reflected.

[0054] As explained above, when the first object 110 passes through the first measurement area Z1, an image B11 containing the image P11 of the first ray L1 is acquired as a first image. Furthermore, when the second object 120 passes through both the first measurement area Z1 and the second measurement area Z2, images B22 and B23 containing the images P21 and P22 of the second ray L2 are acquired as second images. That is, the image of the ray light contained in the image acquired by the imaging unit 20 varies depending on the height of the object.

[0055] Furthermore, when the second object 120 passes through the first measurement area Z1 and the second measurement area Z2, the image captured by the imaging unit 20 changes differently compared to when the first object 110 passes through the first measurement area Z1. Specifically, when the second object 120 passes through the first measurement area Z1 and the second measurement area Z2, images B20, B21, B22, and B23 are captured in that order. Furthermore, when the first object 110 passes through the first measurement area Z1, images B10 and B11 are captured in that order.

[0056] Thus, the image of the linear light contained in the image acquired by the imaging unit 20 and the image transformation vary depending on the height of the object. As a result, the measuring unit 50 is able to determine which of the linear light projected onto the object is the image of the first linear light L1 or the image of the second linear light L2.

[0057] <Effects of Implementation Method 1>

[0058] According to Embodiment 1 described above, the imaging unit 20 of the shape measuring device 100 captures images of a first object 110 passing through a first measuring region Z1 and a second object 120 passing through a second measuring region Z2. The measuring unit 50 measures the shape of the first object 110 based on a first image B11 of the portion of the first object 110 illuminated by the first ray light L1. Furthermore, the measuring unit 50 measures the shape of the second object 120 based on second images B22 and B23 of the portion of the second object 120 illuminated by the second ray light L2. Thus, the shape measuring device 100 can expand the measurement range in the height direction of the object using only one imaging unit 20, and can measure the object with high accuracy. Therefore, a shape measuring device 100 that expands the measurement range and measures the object with high accuracy at low cost can be provided.

[0059] Furthermore, according to Embodiment 1, each imaging unit 20 has multiple measurement areas (i.e., a first measurement area Z1 and a second measurement area Z2) corresponding to the height of the object. Therefore, regardless of whether the shape of the object passing through the first measurement area Z1 or the shape of the object passing through the second measurement area Z2 is measured, the number of pixels in the image processed in the measurement unit 50 is the same. Thus, the computational load in the measurement unit 50 can be reduced, and the computational processing in the measurement unit 50 can be accelerated.

[0060] Furthermore, according to Embodiment 1, compared to a structure where the shape measuring device has two imaging units, synchronous control of the individual images acquired by the two imaging units is not required. Therefore, a simple shape measuring device 100 can be provided. Thus, according to Embodiment 1, a low-cost, computationally-intensive, and simple shape measuring device 100 can be provided.

[0061] Implementation Method 2

[0062] Figure 7 This is a diagram showing the shape measuring device 200 and the object 110 as viewed along the X-axis direction in Embodiment 2. Figure 7 In China, targeting and Figure 2 Structural elements that are the same as or correspond to the structural elements shown are labeled with the same structural elements. Figure 2 The same reference numerals are shown. The shape measuring device 200 of Embodiment 2 differs from the shape measuring device 100 of Embodiment 1 in that, in the Z-axis direction, the length A22 of the second measuring region Z22 is different from the length A21 of the first measuring region Z21. Apart from this, the shape measuring device 200 of Embodiment 2 is the same as the shape measuring device 100 of Embodiment 1.

[0063] like Figure 7 As shown, the shape measuring device 200 includes a light projection unit 10, a photographing unit 220, and a measuring unit 50.

[0064] The imaging unit 220 captures images of the object 110 passing through the first measurement area Z21 and the second measurement area Z22. Here, the first measurement area Z21 is the area where the first plane V1 through which the first ray light L1 passes intersects with the shooting field of view F1 of the imaging unit 220. Furthermore, the second measurement area Z22 is the area where the second plane V2 through which the second ray light L2 passes intersects with the shooting field of view F1 of the imaging unit 220.

[0065] In embodiment 2, the length A22 of the second measurement region Z22 is different from the length A21 of the first measurement region Z21 in the Z-axis direction. Therefore, the resolution in the second measurement region Z22 can be varied relative to the resolution in the first measurement region Z21. Figure 7 In the example shown, length A21 is shorter than length A22. Here, the resolution of each of the first measurement region Z21 and the second measurement region Z22 is a value obtained by dividing the field of view by the number of pixels. In Embodiment 2, the number of pixels when photographing the object 110 passing through the first measurement region Z21 is the same as the number of pixels when photographing the object 110 passing through the second measurement region Z22. Therefore, when length A21 is shorter than length A22, the resolution value in the first measurement region Z21 is smaller than the resolution value in the second measurement region Z22. As a result, the resolution in the first measurement region Z21 can be improved relative to the resolution in the second measurement region Z22.

[0066] By adjusting at least one of the incident angles of the first line light L1 and the second line light L2, the position of the imaging unit 220, and the optical axis angle of the imaging unit 220, the length A21 can be made shorter than the length A22. Alternatively, the length A22 can also be shorter than the length A21. That is, either the length A21 or the length A22 needs to be shorter than the other. Furthermore, as in Embodiment 2, when the lengths A21 and A22 are different, the focal position of the imaging unit 20 is expected to be within the range of the measurement region with the shorter length in the Z-axis direction within the first measurement region Z21 and the second measurement region Z22.

[0067] <Effects of Implementation Method 2>

[0068] According to Embodiment 2 described above, the length A22 of the second measurement region Z22 is different from the length A21 of the first measurement region Z21 in the Z-axis direction. Therefore, the resolution in the first measurement region Z21 can be varied relative to the resolution in the second measurement region Z22.

[0069] In the Z-axis direction, the length A21 of the first measurement region Z21 is shorter than the length A22 of the second measurement region Z22. Therefore, the resolution in the first measurement region Z21 can be improved relative to the resolution in the second measurement region Z22.

[0070] Implementation Method 3

[0071] Figure 8 This is a diagram showing the shape measuring device 300 and the object 110 of Embodiment 3 viewed along the X-axis. Figure 8 In China, targeting and Figure 2 Structural elements that are the same as or correspond to the structural elements shown are labeled with the same structural elements. Figure 2 The same reference numerals are used. The shape measuring device 300 of Embodiment 3 differs from the shape measuring device 100 of Embodiment 1 in that the focal position G1 of the first line light L31 is contained within the first measuring region Z1, and the focal position G2 of the second line light L32 is contained within the second measuring region Z2. Otherwise, the shape measuring device 300 of Embodiment 3 is the same as the shape measuring device 100 of Embodiment 1.

[0072] like Figure 8 As shown, the shape measuring device 300 includes a light projection unit 310, a photographing unit 20, and a measuring unit 50.

[0073] The light-projecting unit 310 includes a collimating lens and a cylindrical lens (e.g., the one described above). Figure 2 The collimating lens 10b and cylindrical lens 10c shown are configured in different ways. The collimating lens collimates the light incident from the point source. The cylindrical lens converges the pattern of light collimated by the collimating lens into a linear shape. The projection unit 310 irradiates a first linear light L31 and a second linear light L32. The first linear light L31 and the second linear light L32 are extended in the Y-axis direction. Figure 8 In the example shown, the width of the first line light L31 in the Y-axis direction is set to w1, and the width of the second line light L32 in the Y-axis direction is set to w2.

[0074] In embodiment 3, the focal point G1 of the first linear light L31, which is the narrowest point of width w1, is included within the first measurement area Z1. Therefore, when the object 110 passes through the first measurement area Z1, the converged first linear light L31 is irradiated onto the object 110. Consequently, the positional accuracy of the image of the first linear light L31 projected onto the object 110 is improved, thus enhancing the accuracy of the height H1 of the object 110 calculated in the measurement unit 50.

[0075] Furthermore, the focal point G2 of the second line light L32, which is the narrowest point of width w2, is contained within the second measurement area Z2. Therefore, when an object passes through the second measurement area Z2, the converged second line light L32 is irradiated onto the object. Consequently, the positional accuracy of the image of the second line light L32 projected onto the object passing through the second measurement area Z2 is improved, thus enhancing the accuracy of the object height calculation in the measurement unit 50.

[0076] For example, by adjusting the position of the collimating lens (not shown) provided in the projection unit 310 in the Z-axis direction to a predetermined position, the focal point position G1 can be included in the first measurement area Z1, and the focal point position G2 can be included in the second measurement area Z2.

[0077] <Effects of Implementation Method 3>

[0078] According to Embodiment 3 described above, the focal position G1 of the first linear beam L31 is included in the first measurement region Z1. Therefore, when the object 110 passes through the first measurement region Z1, the calculation accuracy of the height H1 of the object 110 in the measurement unit 50 can be improved.

[0079] Furthermore, according to Embodiment 3, the focal position G2 of the second linear beam L2 is included in the second measurement region Z2. Therefore, when an object passes through the second measurement region Z2, the accuracy of calculating the height of the object in the measurement unit 50 can be improved.

[0080] Implementation Method 4

[0081] Figure 9 This is a diagram showing the shape measuring device 400 and the object 130 of Embodiment 4 viewed along the X-axis. Figure 9 In China, targeting and Figure 2 Structural elements that are the same as or correspond to the structural elements shown are labeled with the same structural elements. Figure 2 The same reference numerals are shown. The shape measuring device 400 of Embodiment 4 differs from the shape measuring device 100 of Embodiment 1 in that it also has a second light projection unit 30 and a second imaging unit 40. Apart from this, the shape measuring device 400 of Embodiment 4 is the same as the shape measuring device 100 of Embodiment 1.

[0082] Figure 9 The object 130 shown is an example of an object to be measured. The shape of object 130 differs from the shapes of the first object 110 and the second object 120 in Embodiment 1. Figure 9In the example shown, the object 130 has a trapezoidal shape when viewed along the X-axis. That is, in Embodiment 4, the sides 132 and 133 of the object 130 facing the Y-axis are inclined surfaces. In the shape measuring device 100 of Embodiment 1 (for example, refer to...) Figure 1 and 2 When determining the shape of the object 130, the first imaging unit 20 can capture the pattern of line light projected onto the side 132 in the -Y-axis direction. However, depending on the magnitude of the gradient of the side 133 in the +Y-axis direction, the first imaging unit 20 cannot capture the pattern of line light projected onto the side 133. Thus, depending on the shape of the object 130, sometimes a blind spot (e.g., the side 133 in the +Y-axis direction) is formed that cannot be captured by the first imaging unit 20.

[0083] The shape measuring device 400 includes a first projection unit 10, a first imaging unit 20, a second projection unit 30, a second imaging unit 40, and a measuring unit 50.

[0084] The second projection unit 30 illuminates a third line light L3 and a fourth line light L4, both of which are linear lights. The third line light L3 and the fourth line light L4 are rays that extend along the X-axis. The third line light L3 and the fourth line light L4 are projected onto the surface of the object 130. The images of the third line light L3 and the fourth line light L4 projected onto the surface of the object 130 are each linear in shape extending along the X-axis.

[0085] The fourth line light L4 is illuminated from a position separated from the third line light L3 along the Y-axis, which is the scanning direction. The fourth line light L4 is parallel to the third line light L3 along the X-axis. Alternatively, the fourth line light L4 is not limited to the X-axis direction; it can be parallel to the third line light L3 in a predetermined direction.

[0086] The second projection unit 30 is positioned closer to the +Y axis than the first projection unit 10. The illumination directions of the third line light L3 and the fourth line light L4 are different from those of the first line light L1 and the second line light L2. The third line light L3 and the fourth line light L4 illuminate the side 133 of the object 130 that cannot be photographed by the first imaging unit 20 and faces the +Y axis.

[0087] The second imaging unit 40 has a second imaging field of view F2, which is different from the first imaging field of view F1. The direction of the second imaging field of view F2 is different from the illumination direction of the third line light L3 and the fourth line light L4 irradiated by the second projection unit 30. The second imaging unit 40 is, for example, a camera with a CCD image sensor. The second imaging unit 40 captures the object 130 passing through the third measurement area Z3. Here, the third measurement area Z3 is the area where the third plane V3, through which the third line light L3 passes, intersects with the second imaging field of view F2. The third plane V3 is an imaginary XZ plane. Figure 9 In the example shown, the height H3 of the object 130 from the reference plane S is included in the third measurement region Z3 and the first measurement region Z1. Furthermore, the third and fourth rays L3, depending on the angle of incidence, sometimes do not irradiate the XZ plane, but rather illuminate along it. Therefore, the third plane V3 and the fourth plane V4 through which the fourth ray L4 (described later) passes are respectively referred to as the "imaginary XZ plane".

[0088] Furthermore, the second imaging unit 40 images the object passing through a fourth imaging region Z4, which is different from the third imaging region Z3. The fourth imaging region Z4 is the area where the fourth plane V4, through which the fourth ray light L4 passes, intersects with the second imaging field of view F2. The fourth plane V4 is an imaginary XZ plane.

[0089] The fourth measurement region Z4 is positioned closer to the second projection section 30 (i.e., the +Z-axis side) than the third measurement region Z3. The fourth measurement region Z4 is adjacent to the third measurement region Z3 in the Z-axis direction. Furthermore, the fourth measurement region Z4 does not overlap with the third measurement region Z3 in the Z-axis direction. Additionally, as long as most of the fourth measurement region Z4 does not overlap with the third measurement region Z3, a portion of the fourth measurement region Z4 may overlap with the third measurement region Z3. That is, the fourth measurement region Z4 only needs to include an area that does not overlap with the third measurement region Z3.

[0090] Here, the incident angle of the fourth light beam L4 is different from that of the third light beam L3. Therefore, the fourth measurement region Z4 can be made different from the third measurement region Z3. In Embodiment 4, the fourth light beam L4 is incident on the object 130 along the normal to the reference plane S; therefore, the incident angle of the fourth light beam L4 is 0 degrees. In contrast, the incident angle of the third light beam L3 is greater than 0 degrees. Alternatively, the incident angle of the fourth light beam L4 can also be the same as that of the third light beam L3.

[0091] Furthermore, by adjusting the position and optical axis angle of the second imaging unit 40, the fourth measurement region Z4 can be made to be a region different from the third measurement region Z3. Moreover, the optical axis of the second imaging unit 40 is positioned on the opposite side of the optical axis of the first imaging unit 20, separated from the centerline C passing through the center of the object 130 in the Y-axis direction and perpendicular to the reference plane S. In other words, the second imaging unit 40 is positioned on the opposite side of the first imaging unit 20 in the Y-axis direction, separated from the first projection unit 10 and the second projection unit 30.

[0092] The measuring unit 50 measures the shape of the object 130 based on an image containing an image of linear light obtained by the first imaging unit 20 and an image containing an image of linear light obtained by the second imaging unit 40.

[0093] When the height H3 of the object 130 is contained within the first measurement area Z1 and the third measurement area Z3, the measurement unit 50 measures the shape of the object 130 based on the first image and the third image. The first image is an image of region 131a of the object 130, which is the portion of the object 130 illuminated by the ray light L1, i.e., the upper surface 131. The third image is an image of region 131b of the object 130, which is the portion of the object 130 illuminated by the third ray light L3, i.e., the upper surface 131. Thus, for the region 131b of the object 130 that is a blind spot of the first imaging unit 20, the shape of the object 130 can be measured based on the third image obtained by the second imaging unit 40.

[0094] Assuming that the height H3 of the object 130 is contained within the second measurement region Z2 and the fourth measurement region Z4, the measurement unit 50 measures the shape of the object 130 based on the second image and the fourth image. The second image is an image of the portion of the object 130 illuminated by the second line light L2, and the fourth image is an image of the portion of the object 130 illuminated by the fourth line light L4.

[0095] Here, the images acquired by the first imaging unit 20 and the second imaging unit 40 are sometimes the same. In this case, the measuring unit 50 calculates data representing the height information of the object 130 based on both the images acquired by the first imaging unit 20 and the images acquired by the second imaging unit 40. Alternatively, the measuring unit 50 may also calculate the above data based on only one of the images acquired by the first imaging unit 20 and the images acquired by the second imaging unit 40.

[0096] <Effects of Implementation Method 4>

[0097] According to Embodiment 4 described above, the shape measuring device 400 is provided with a second projection unit 30 and a second imaging unit 40. Therefore, it is possible to measure the shape of the area of ​​the object 130 that is a blind spot of the first imaging unit 20 (specifically, the side 133 facing the +Y axis direction), that is, the shape of the obstructed portion of the object 130.

[0098] Explanation of reference numerals in the attached figures

[0099] 10 First projection unit, 20, 220 First imaging unit, 30 Second projection unit, 40 Second imaging unit, 50 Measuring unit, 100, 200, 300, 400 Shape measuring device, 110, 120, 130 Object, A1, A2, A3, A4, A21, A22 Length, B10, B11, B20, B21, B22, B23 Image, F1 First imaging field of view, F2 Second imaging field of view, G1, G2 Focal position, L1, L31 First line light, L2, L32 Second line light, L3 Third line light, L4 Fourth line light, V1 First plane, V2 Second plane, V3 Third plane, V4 Fourth plane, Z1, Z21 First measuring area, Z2, Z22 Second measuring area.

Claims

1. A shape measuring device, characterized in that, have: The first projection unit illuminates a first line of light as a linear light and a second line of light as a linear light. The first imaging unit has a first imaging field of view, which captures an object passing through a first measurement area and captures the same object passing through a second measurement area. The first measurement area is the area where a first plane through which the first ray light passes intersects with the first imaging field of view. The second measurement area is the area where a second plane through which the second ray light passes intersects with the first imaging field of view. The second measurement area is different from the first measurement area and is located closer to the first projection unit than the first measurement area. as well as The measuring unit determines whether the image of the linear light projected onto the object is the image of the first linear light or the image of the second linear light, and measures the shape of the object based on the first image and the second image according to the determination result. The shape includes the height of the object. The first image is an image of the portion of the object illuminated by the first linear light through the first measuring area, and the second image is an image of the portion of the object illuminated by the second linear light through the second measuring area.

2. The shape measuring device according to claim 1, characterized in that, The second angle of incidence is greater than or equal to the first angle of incidence. The second angle of incidence is the angle of incidence of the second ray light incident on the object, and the first angle of incidence is the angle of incidence of the first ray light incident on the object.

3. The shape measuring device according to claim 2, characterized in that, The second incident angle is larger than the first incident angle.

4. The shape measuring device according to any one of claims 1 to 3, characterized in that, In the direction of the height of the object from the reference plane on which the object is placed, the length of one of the lengths of the second measuring region and the first measuring region is less than the length of the other.

5. The shape measuring device according to claim 4, characterized in that, The length of the first measurement region is shorter than the length of the second measurement region.

6. The shape measuring apparatus according to any one of claims 1 to 3, characterized in that, The focal position of the first line of light is contained within the first measurement region.

7. The shape measuring apparatus according to any one of claims 1 to 3, characterized in that, The focal position of the second line of light is contained within the second measurement region.

8. The shape measuring apparatus according to any one of claims 1 to 3, characterized in that, The shape measuring device also has: The second projection section illuminates a third line of light and a fourth line of light, both of which are linear beams; and The second imaging unit has a second imaging field of view different from the first imaging field of view. It images objects passing through a third measurement area and objects passing through a fourth measurement area. The third measurement area is the region where a third plane through which the third ray light passes intersects with the second imaging field of view. The fourth measurement area is the region where a fourth plane through which the fourth ray light passes intersects with the second imaging field of view. The fourth measurement area is different from the third measurement area and is positioned closer to the second projection unit than the third measurement area. The measuring unit measures the shape of the object based on the first image, the second image, the third image, and the fourth image. The third image is an image of the portion of the object illuminated by the third line of light in the third measuring area, and the fourth image is an image of the portion of the object illuminated by the fourth line of light in the fourth measuring area.

9. The shape measuring device according to claim 8, characterized in that, The illumination directions of the third and fourth light rays are different from those of the first and second light rays.

Images