JP2002257527A - 3D measuring method and 3D measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional measuring method and a three-dimensional measuring apparatus for measuring a three-dimensional shape of an object surface without contact.

[0002]

2. Description of the Related Art Conventionally, non-contact three-dimensional shape measurement methods include a light cutting method and a grid pattern projection method.
In the light cutting method, a slit light is irradiated toward an object to be measured. Since the slit light irradiated on the measured object is deformed according to the surface shape, the deformed slit light is photographed by the area sensor. Then, the three-dimensional shape of the measured object is calculated from the observed shape of the slit light. On the other hand, in the grid pattern projection method, a grid pattern is projected on an object to be measured instead of slit light, and the projected grid pattern is photographed by an area sensor. Also in this case, the three-dimensional shape of the measured object is calculated from the shape of the deformed grid pattern.

As another measuring method, there is a three-dimensional shape measuring method using moire fringes. This includes a method called grating irradiation type moire topography and a method called grating projection type moire topography. In the grid-illuminated moire topography, parallel, equally spaced gratings are arranged immediately before an object to be measured, and they are illuminated with illumination light to form a shadow of the grating on the surface of the object to be measured. This shadow is deformed according to the surface shape, but when this deformed shadow is observed through a grid, moire fringes are generated.

[0004] On the other hand, in the grating projection type moire topography, a grating image is projected on the surface of an object by a projection optical system, and a grating image distorted according to the surface shape is formed by an observation optical system. When observed through the arranged observation grating, moire fringes occur. Since the moiré fringes are contour lines of the object to be measured, the three-dimensional shape of the object to be measured can be calculated from the contour lines.

[0005]

In the light cutting method and the grid pattern projection method described above, the height of the object to be measured is calculated based on the slit light and the deformation amount of the grid pattern.
In order to increase the height measurement resolution, it is necessary to increase the angle between the irradiation optical axis of the slit light or the grating pattern and the optical axis of the area sensor. However, when this angle is increased, there is a problem in that a portion to be measured tends to be a shadow of light in an object to be measured having severe unevenness, and a portion that cannot be measured increases.

In the method using moire fringes, a grid pattern on an object to be measured is observed through a grid.
There is a drawback that the image of the lattice is reflected. Further, in the grating irradiation type moire topography, there is a problem that a grating having a size substantially equal to that of an object to be measured is required. Also, when trying to change the interval between moiré stripes,
It was necessary to replace the grid with a different pitch. On the other hand, in the grid projection type moire topography, it is necessary to accurately align the projection grid and the observation grid, and there is a problem that alignment is difficult.

An object of the present invention is to provide a three-dimensional measuring method and a three-dimensional measuring apparatus which can easily measure a three-dimensional shape even of a measured object having large irregularities and can easily increase a measuring resolution in a height direction. Is to provide.

[0008]

An embodiment of the present invention will be described with reference to FIG. (1) In the three-dimensional measurement method according to the first aspect of the present invention, a grid pattern P ′ composed of a plurality of linear patterns parallel to each other is projected on the measured object 6, and the projected grid pattern P ′ and the line sensor 4 are covered. The line sensor 4 captures an image of the projected grid pattern P ′ while moving relative to the measurement object 6 integrally, and the three-dimensional shape of the measured object 6 based on the image of the grid pattern P ′ in the captured image. The above-mentioned object is achieved by measuring. (2) The three-dimensional measuring apparatus according to the second aspect of the present invention includes: a projection device 1 for projecting a grid pattern P ′ composed of a plurality of straight line patterns parallel to each other onto an object 6 to be measured; Line sensor 4 for imaging pattern P '
And the projected grating pattern P ′ and the line sensor 4
A moving device 7 for integrally moving the object relative to the measured object 6 and a computing device for calculating the three-dimensional shape of the measured object 6 based on the image of the grid pattern P ′ in the image captured by the line sensor 4 111 to achieve the above object. (3) The three-dimensional measuring apparatus according to the second aspect, wherein the line sensor 4 captures the line sensor 4 on the measured object 6 in the extending direction of the linear pattern projected on the measured object 6. The angle θ with respect to the direction in which the region 10 extends is substantially zero. (4) In the three-dimensional measuring apparatus according to the second aspect, the linear imaging of the line sensor 4 on the object 6 and the extending direction of the linear pattern projected on the object 6 to be measured. An angle changing device 12 for changing an angle θ with respect to the extending direction of the region 10 is provided.

In the meantime, in the section of the means for solving the above problems, the drawings of the embodiments of the present invention are used to make the present invention easy to understand, but the present invention is not limited to the embodiments of the present invention. Not something.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing one embodiment of a three-dimensional measuring apparatus according to the present invention, and is a view showing a schematic configuration of the apparatus. The three-dimensional measuring apparatus includes a projection unit 1 that projects a projection grid pattern P ′ onto a work 6 that is an object to be measured, and an imaging unit 8 that captures the projected projection grid pattern P ′. The work 6 is placed on a moving device 7 that can move in the x direction.

The projection section 1 is provided with a light source 2, a projection grid pattern P, a projection lens 3, and an angle changing mechanism 12 for changing the angle of the grid pattern P about the projection optical axis. The imaging unit 8 includes a line sensor 4 that captures an image of a region of the work 6 on which the projection grid pattern P ′ is projected, and an observation lens 5. By changing the angle of the grid pattern P by the angle changing mechanism 12, the angle θ between the longitudinal direction of the imaging region 10 of the line sensor 4 on the workpiece 6 and the extension direction of the linear pattern of the projection grid pattern P ′ can be changed. it can. Generally, a halogen lamp, a laser light source, or the like is used as the light source 2, but there is no particular limitation. In addition, a moving stage or the like is used for the moving device 7, but when the work 6 is a long object, a belt conveyor, a slide rail, or the like may be used.

The image captured by the line sensor 4 is sent to an image processing unit 110 of the controller 11 and is subjected to image processing. The calculation unit 111 calculates the three-dimensional shape of the work 6 based on the image data from the image processing unit 110.
The angle changing mechanism 12 and the moving device 7 are controlled by the controller 11.

Although not shown in FIG. 1, the projection lens 3 for projecting the lattice pattern P onto the work 6 is provided with a focus adjusting device and a projection magnification adjusting device. Therefore, according to the size of the work 6, the projection grid pattern P '
Can be adjusted, or the grid spacing of the projection grid pattern P ′ can be adjusted.

In the measuring apparatus shown in FIG. 1, there is no restriction on the positional relationship between the projection unit 1, the imaging unit 8, and the moving device 7 and their directions. However, the optical axis of the projection unit 1 and the imaging unit 8
So that the angle between the optical axis and the optical axis does not become zero, that is,
Set so that both optical axes are not parallel. Hereinafter, in order to simplify the description, a case where the line sensor 4 images the work 6 from the vertical direction will be described as an example. Also,
The extending direction of the imaging area 10 of the line sensor 4 was set to be 90 degrees with respect to the moving direction R of the moving device 7.

Next, an image obtained when the grid pattern P is projected onto the work 6 which is the object to be measured and the projected grid pattern P 'is picked up by the line sensor 4 will be described. FIG. 2A is a plan view of the flat work 6 as viewed from directly above, and the projection lattice pattern P ′ is projected from obliquely above the work 6. In the example shown in FIG.
The lattice pattern P has five stripe patterns P1 to P5, and projection stripe patterns P1 ′ to P5 ′ corresponding to the respective stripe patterns P1 to P5 are projected on the work. These projection stripe patterns P1 ′ to P5 ′ are projected so as to form an angle θ (where θ た だ し 0) with respect to the imaging region 10.

Since the imaging region 10 is linear (two-dimensional), only the intersection patterns C2, C3, and C4 that intersect with the imaging region 10 in the projection stripe patterns P1 'to P5' on the work 6 are imaged. . When the work 6 is imaged by the line sensor 4 while moving in the R direction, the image of the work 6 captured by the line sensor 4 includes the intersection patterns C2, C3, C
Trajectories L2, L3, and L4, which are images of No. 4, are formed. In the case of the flat work 6, the trajectories L2, L3, and L4 are in the work moving direction R
It becomes a straight line parallel to.

In general, if the intervals between the projection stripe patterns P1 'to P5' are d11, d12, d13, and d14, the trajectories L2, L3,
The intervals d22 and d23 of L4 are calculated by equation (1).

## EQU00001 ## d2j = d1j / sin .theta. (J = 1, 2) (1) However, when the surface of the grid pattern P is arranged so as to be parallel to the surface of the work 6, or it is telecentric to the projection optical system. When an optical system is used, the projection fringe patterns P1 'to P1
In 5 ', each interval is equal to d11 = d12 = d13 = d14.

The intervals d22 and d23 are determined by the intersection pattern C2.
The direction in which the workpiece 6 moves with respect to .about.C4 also depends. For example, when the workpiece 6 is moved in a direction R ′ at an angle α with respect to the direction R as shown in FIG.
The distance d23 'between L3 and the trajectory L4 is as shown in the following equation (2).

D2 ′ = d22 · sinα (2) FIG. 2C shows the work 6 imaged by the line sensor 4.
It is an image of. Intersection patterns C2 and C
Trajectories L2, L3, L4 of C3 and C4 are formed.

[Measurement Object with Step] In the example shown in FIG. 2, the trajectory formed on a plane having the same height has been described. Next, a trajectory in the case where the height of the work surface varies depending on the location will be described. FIG. 3A is a perspective view illustrating an appearance of the work 16. On the upper surface of the work 16, two horizontal planes 161 and 162 having different heights and a slope 163 connecting these planes 161 and 162 are formed. The height difference between the plane 161 and the plane 162 is h
It is. The projection direction of the grid pattern P, the workpiece moving direction R, and the arrangement of the line sensor 4 are the same as those in FIG.

There is a height difference h between the plane 161 and the plane 162, and the image of the lattice pattern P is projected onto the work 16 from obliquely above. Therefore, as shown in FIG. 3B, the projection pattern PU on the plane S1 including the plane 161 and the projection pattern PL on the plane S2 including the plane 162 are projection images of the same pattern, but are projected in the horizontal direction. The position shifts. Further, the sizes of the projection patterns PU and PL on the respective planes S1 and S2 are also different.

FIGS. 4A to 4C are diagrams for explaining the relationship between the projection pattern and each of the surfaces 161, 162, 163 of the work 16. In each case, the work 16 is viewed from the z direction. It is a top view. FIG. 4A is a diagram illustrating a projection pattern projected on planes S1, S2, and S3 having different heights. The plane S3 is a plane at a height h / 2 from the plane S2. PU4, PL4, and PM4 have stripe patterns P4, which are part of the lattice pattern P (see FIG. 2), on the respective planes S1 to S3.
Is a projection pattern that is projected onto the projection pattern. The pattern PU4 is projected on the plane S1, the pattern PL4 is projected on the plane S2, and the pattern PM4 is projected on the plane S3. Figure 1
When viewed from the line sensor 4 side (z direction), the projection patterns PU4, PL4, PM4 to be observed are parallel to each other, and each form the same angle θ with the imaging region 10.

CU4, CL4 and CM4 are patterns PU4 and PU4, respectively.
An intersection pattern where PL4, PM4 intersects with the imaging region 10 is shown. When the planes S1, S2, and S3 move in the work moving direction R, the intersection patterns CU4 and CL appear on the image of the planes S1, S2, and S3 captured by the line sensor 4.
4, trajectories LU4, LL4, and LM4, which are images of CM4, are formed.
Since the height of the plane S3 is located between the plane S1 and the plane S2, the horizontal distance between the trajectory LL4 and the trajectory LU4 is d3.
Assuming that 4, the horizontal distance between the trajectories LL4 and LU4 and the trajectory LM4 is d34 / 2, respectively. That is, the plane S2
On a plane higher by a height ha (where 0 ≦ a ≦ 1), a locus shifted downward in the drawing by a horizontal interval d3 · a with respect to the locus LL4 is formed.

Therefore, the planes 161, 16 of the work 16
2, an intersection pattern CU4, C as shown in FIG.
Trajectories LU4 and LL4 of L4 are formed, and the trajectory LL is formed on the slope 163.
A locus LS4 connecting the locus 4 and the locus LU4 is formed. The intersection pattern CM4 is located at an intermediate point of the locus LS4.

FIG. 4C is a diagram showing a trajectory formed on the image of the work 16. Trajectories LL2, LL on the plane 162
3 and LL4 are formed at intervals d22 and d23, and trajectories LU2, LU3 and LU4 are formed at intervals d42 and d43 on the plane 161 and the slope 16
Trajectories LS2, LS3, LS4 are formed on 3. Locus LU2, LS
2 and LL2 constitute one continuous trajectory L2, and similarly, trajectories LU3, LS3 and LL3 constitute one continuous trajectory L3
And the trajectories LU4, LS4 and LL4 constitute one continuous trajectory L4.

The plane 162 has the same height as the surface of the work 6 in FIG. 2, and the intervals between the trajectories LL2 to LL4 formed on the plane 162 are d22 and d23 as in the case of FIG. 2C. on the other hand,
Locus LU formed on plane 161 higher than plane 162
The intervals between 2, LU3 and LU4 are d42 and d43, and d42 <d2, respectively.
2, d43 <d23. Therefore, the displacement amount d32 of the locus LU2 with respect to the locus LL2, and the locus LU3 with respect to the locus LL3
Of the locus LU4 with respect to the locus LL4 will be different.

When the upper surface of the work is a plane having a constant height as in the case of the flat work 6 described above, the trajectories L2 to L4 are straight lines as shown in FIG. On the other hand, in the work 16 having a step, the height difference h between the plane 161 and the plane 162 is determined.
Therefore, there is a horizontal displacement d between the locus LU4 formed on the plane 161 and the locus LL4 formed on the plane 162.
3 results. At this time, the deviation amount per unit height is d34
/ H.

For example, since the point CM4 on the locus LS4 in FIG. 4B is shifted downward by d34 / 2 from the locus LL4 in the drawing, the height of the point CM4 is higher than that of the plane 162 by the following equation (3). It will be higher by Δh shown by. As described above, when the plane 161 is used as a reference for the height, how many parts LU2 to LU4 formed on the plane 162 correspond to parts LL2 to LL4 formed on the plane 161 of the trajectories L2 to L4 The height of the plane 162 with respect to the plane 161 can be calculated by detecting whether the plane 162 is shifted.

Δh = (d34 / 2) ÷ (d34 / h) = h / 2 (3)

[Difference in Measurement Resolution Depending on Angle θ] Next, the difference in resolution for height measurement depending on the magnitude of the angle θ will be described. FIG. 5 is a diagram illustrating a trajectory formed on the image of the work 16 when the angles of the projection patterns PU4 and PL4 and the imaging area 10 of the line sensor 4 are different. FIG. 5A shows a case where the angle is θ, and FIG.
Indicates the case of the angle θ ′ (<θ).

The displacement amount d3 of the locus LU4 of the intersection pattern CU4 with respect to the locus LL4 of the intersection pattern CL4 is the projection pattern PL4
And by using the horizontal distance d1 between PU4 and PU4. On the other hand, in the case of the angle θ ′, it is expressed as Expression (5). Then, as shown in Expression (6), the shift amount d34 ′
Is (sin θ / sin θ ′) times the shift amount d34.

D34 = d1 / sinθ '(4) d34' = d1 / sinθ '(5) d34' / d34 = sinθ / sinθ '> 1 (6)

The resolution of the image pickup is determined by how many image pickup elements the line sensor 4 has per unit length. In order to increase the height measurement resolution for a certain amount of deviation, it is necessary to increase the element density of the line sensor 4. However, in the present embodiment, the shift amount can be increased by changing the angle θ, so that the height measurement resolution can be improved without changing the element density of the line sensor 4. That is, the angle is θ
Is changed to θ ', the height measurement resolution becomes (sin θ / s
inθ ′) times.

As described above, in the conventional light sectioning method and the lattice pattern projection method, the z-axis (FIG. 1) of the projection optical axis and the imaging optical axis is used.
The angle from is increased to increase the deformation of the observed slit light and lattice pattern, thereby increasing the resolution of height measurement. Therefore, there is a problem that a shadow portion is easily formed due to unevenness of the measured object, and a portion that cannot be measured becomes large. However, in the measuring device of the present embodiment, for example, the angle between the projection optical axis and the imaging optical axis is changed by changing the angle of the lattice pattern P by the angle changing mechanism 12 in FIG. The resolution can be easily increased without any problem.

Therefore, it is possible to solve the problem that the unmeasurable portion increases as the resolution increases, as in the related art. For example, by arranging the line sensor 4 directly above the work as shown in FIG. 1 and arranging the projection angle of the grid pattern P so as to be as close to the top as possible,
The shadow portion can be made smaller.

As can be seen from FIG. 5, as the angle θ decreases, the length of the intersection patterns CL4 and CU4 in the vertical direction in the drawing increases, so that the smaller the angle θ increases the width of the trajectories LL4 and LU4. From the above equation (1), the angle θ
Is smaller, the interval d2 between the trajectories LL2 to LL4 is larger.

FIGS. 6 and 7 are diagrams for explaining the difference in the locus (striped pattern) due to the difference in the angle θ. FIG. 6 is a view showing an object to be measured. A plate 21 bent in a “W” shape was placed on the flat plate 20, and measurement was performed by moving the flat plate 20 in the R direction. FIG. 7 is a diagram illustrating an image captured by the line sensor, and FIG. 7A illustrates a case where the angle θ is θ1,
(B) is a case where the angle θ is θ2 (> θ1).

In FIG. 7A, LL1 to LL3 are flat plates 20.
It is a locus formed above. On the other hand, LS1 to LS3 are bent plate 2
1 are trajectories formed on the slope 1 and are respectively trajectories LL1
~ LL3 is supported. Trajectory LL1 to trajectory LL1 to LL3
The shape of the bent plate 21 can be measured by detecting the amount of displacement of the LL3. In the case of the angle θ2, it can be seen that the width dimension and the interval (d2 in FIG. 2) of the stripe pattern are large.
In the case of FIG. 7A, the deviation amount of the locus LS3 at the vertex of the bending plate 21 from the locus LL3 on the flat plate 20 is
d3 '. On the other hand, the similar displacement amount in the case of FIG. 7B is d3, which is smaller than d3 ′ in FIG. 7A. That is, the resolution of the height measurement is higher in FIG.

[When Angle θ is θ = 0 or θ ≒ 0] Next, the locus when the angle θ is θ = 0 or θ ≒ 0 will be described. FIG. 8A is a perspective view showing the shape of the work 30 to be measured. The work 30 is a horizontal plane 30
1, 302, and slopes 303, 304a, 304b connecting the plane 301 and the plane 302. R is a work moving direction.

FIG. 9 is a diagram showing the relationship between the grid pattern P and the projected grid pattern P '. FIG. 9A shows FIG. 3B.
FIG. The plane S1 is the plane 301 of the work 30.
8A, and the plane S4 is a plane including the plane 302 of the work 30. FIG. 9B shows the plane S.
FIG. 2 is a diagram showing a projection grid pattern P ′ projected on No. 1;
Projection fringe patterns P1 ', P2', P of the projection grid pattern P '
3 ′, P 4 ′, and P 5 ′ are projected so as to be parallel to the extending direction of the imaging region 10. On the plane S1, the imaging area 10 is located between the projection stripe pattern P1 'and the projection stripe pattern P2' on the plane S1. Therefore, the plane S1
Is moved in the work moving direction R, only the plane S1 is photographed in the image.

As shown in FIG. 9A, the projection grid pattern P 'is projected from obliquely above the plane S1. Therefore, the optical path of the projection fringe patterns P2 'to P5'
Intersect the imaging area 10 at heights h12, h13, h14, and h15, respectively. The height of the plane S4 is h14, and FIG.
As shown in (c), the projection fringe pattern P4 'is projected so as to overlap the imaging region 10 on the plane S4. for that reason,
The intersection pattern C4 has the same length d10 as the projection stripe pattern P4 '.
When the plane S4 moves in the workpiece movement direction R, a locus L4 having a width d10 is formed on the image of the plane S4. Normally, the projection range of the imaging region 10 and the projection fringe pattern P4 'is larger than the width of the work, that is, the length in the direction perpendicular to the work moving direction R, so that the plane 3 having the height h14 is used.
02 is entirely imaged in the same color as the projection stripe pattern P4 '. The intersection patterns C2 and C3 at the heights h12 and h13 are the same as the intersection pattern C4, and the plane having the same height as the planes S2 and S3 is entirely imaged in the same color as the projection stripe pattern.

As described above, when the imaging area 10 and the projection fringe patterns P2 'to P5' are substantially parallel, that is, when the angle θ is θ
= 0 or θ ≒ 0, the work surface height h1
Only h2, h13, h14, and h15 are imaged in the same color as the projection stripe pattern. Therefore, in the case of the work 30 as shown in FIG. 8A, as shown in FIG. 8B, the entire plane 302 is imaged in the same color as the projection stripe pattern, and
Trajectories L2 and L3 of the intersection patterns C2 and C3 are formed at the heights h12 and h13 of 3, 304a and 304b. That is, the trajectories L2 and L3 are contour lines of the work 30, and a stripe pattern similar to the moire stripe is obtained.

FIG. 10 is a diagram showing the difference in the stripe pattern between the case where the angle θ is substantially zero and the case where θ ≠ 0. FIG. 10A is a perspective view of an object to be measured, in which a plate 41 bent in a mountain shape on a flat plate 40 is placed. The line sensor 4 captures an image while moving the flat plate 40 in the R direction. FIG. 10B is an image when the angle θ is almost zero, and the trajectories 411 and 412 on the bending plate 41 can be regarded as contour lines. Strictly speaking, θ is not equal to 0, and the trajectories 411 and 412 are slightly inclined with respect to the horizontal plane. Can be seen.

On the other hand, FIG. 10C shows an image when the angle θ is θ ≠ 0. A locus 413 parallel to the moving direction is formed on the flat plate 40, and the locus 413 is also continuous on the bent plate 41. A trajectory 414 is formed. Since the surface on which the trajectory 414 is formed is higher on the left side in the figure, it is inclined downward and left.

As described above, there is no restriction on the positional relationship between the projection unit 1, the imaging unit 8 and the moving device 7 of the measuring device shown in FIG. 1 and their directions, but as shown in FIG. When the grid pattern is projected along the direction in which the imaging region 10 extends, the height resolution does not change even if the angle θ between the pattern P1 ′ and the longitudinal direction of the imaging region 10 is changed. Figure 1
1B shows a case where the angle θ is 90 degrees, and FIG. 1C shows a case where the angle θ is smaller than 90 degrees. Patterns P1U ′ and P1L ′ corresponding to the pattern P1 ′ in FIG. 9A are projected onto the planes SU and SL having different heights. In any case, the horizontal distance between the intersection pattern CU on the plane SU and the intersection pattern CL on the plane SL is equal to d6. That is, even if the angle θ is changed, the displacement of the trajectory does not change, so that the resolution does not change.

In the above description, the line sensor 4 is arranged so as to take an image from the z direction so as to look down on the work from directly above. However, the line sensor 4 may be arranged so as to look down obliquely. Further, the work moving direction R is perpendicular to the extending direction of the imaging region 10, but may be inclined. In this case, the range of the work that can be imaged by the line sensor 4 (the range in the direction perpendicular to the R direction) is reduced, but the resolution of the image is improved.

In the correspondence between the embodiment described above and the elements of the claims, P1 ′ to P5 ′, PU, P
M and PL represent the projected straight line pattern,
Denotes an object to be measured, the projection unit 1 denotes a projection device, and the calculation unit 111
Represents an arithmetic device, and the imaging region 10 constitutes a linear imaging region.

[0045]

As described above, (1) According to the first to fourth aspects of the present invention, the grid pattern can be placed in a direction more directly above the object to be measured without lowering the height measurement resolution. Can be projected. In addition, the imaging by the line sensor can be performed from a direction closer to right above without lowering the height measurement resolution. As a result, it is possible to reduce the size of the unmeasurable region that becomes the shadow of the unevenness of the measured object. (2) According to the third aspect of the invention, the striped pattern formed on the image of the measured object can be regarded as a substantially contour line, and the shape measurement is facilitated. (3) According to the fourth aspect of the present invention, the height measurement resolution can be easily changed by changing the angle by the angle changing device. As a result, shape measurement can be performed with high resolution.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an embodiment of a three-dimensional measuring apparatus according to the present invention, and is a view illustrating a schematic configuration of the apparatus.

FIGS. 2A and 2B are diagrams illustrating trajectories L2 to L4 on a work 6, in which FIG. 2A is a plan view of a projection grid pattern P ′ projected on the work 6, and FIG. Figure,
(C) is a diagram showing trajectories L2 to L4 on the work 6.

3A and 3B are diagrams for explaining measurement of a work 16 having a step, wherein FIG. 3A is a perspective view of the work 16, and FIG.
FIG. 3 is a diagram showing patterns PU and PL projected on S1 and S2.

4A and 4B are diagrams illustrating a trajectory formed on an image of a work 16; FIG. 4A illustrates planes S1 to S3 and patterns PU4 and PL;
4A and 4B are diagrams showing a relationship with PM4, and FIG.
It is a figure explaining locus L4 on 63, (c) is a surface 161
It is a figure which shows the locus | trajectory L2-L4 on -163.

5A and 5B are diagrams for explaining a difference in resolution depending on an angle θ, wherein FIG. 5A illustrates a case of an angle θ, and FIG.
θ) respectively.

FIG. 6 is a perspective view of a flat plate 20 and a bent plate 21 which are objects to be measured.

7A and 7B are diagrams showing measurement images of the flat plate 20 and the bending plate 21, wherein FIG. 7A shows a case where the angle is θ1, and FIG.
(> Θ1).

8A and 8B are diagrams illustrating a case where an angle θ is θ = 0 or θ ≒ 0, where FIG. 8A is a perspective view of a work 30 and FIG. 8B is a diagram illustrating a trajectory formed on an image of the work 30. It is.

9A and 9B are diagrams illustrating a trajectory when the angle θ is θ = 0, where FIG. 9A is a diagram illustrating a relationship between a grid pattern P and a projected grid pattern P ′, and FIG. FIG. 4C is a plan view of the lattice pattern P ′, and FIG. 4C is a trajectory L4 formed on the plane S1.
FIG.

10A and 10B are diagrams for comparing and explaining a case where the angle θ is substantially zero and a case where θ ≠ 0, wherein FIG. 10A is a perspective view of a bending plate 41 placed on a plane 40, and FIG. FIG. 7C is a diagram showing a measurement image when is substantially zero, and FIG. 7C is a diagram showing a measurement image when θ ≠ 0.

FIG. 11 is a diagram illustrating a case where a grid pattern is projected from an extension of a scanning direction of the line sensor 4,
(A) is an imaging direction of the line sensor 4 and a pattern P ′.
FIGS. 7B and 7C show the projection directions of FIG. 7, wherein FIG. 7B shows a case where the angle θ is 90 degrees and FIG. 7C shows a case where the angle θ is smaller than 90 degrees.

[Description of Signs] 1 Projection unit 2 Light source 3 Projection lens 4 Line sensor 5 Observation lens 6, 16 Work 7 Moving device 8 Imaging unit 10 Imaging area 11 Controller 12 Angle changing mechanism 110 Image processing unit 111 Operation unit P Grid pattern P 'projection grid pattern

Claims (4)

[The claims] 1. A grid pattern composed of a plurality of linear patterns parallel to each other is projected onto an object to be measured, and the projected grid pattern and the line sensor are moved integrally with respect to the object to be measured while the projected grid pattern and the line sensor are moved relative to the object to be measured. A three-dimensional measurement method, wherein the three-dimensional shape of the measured object is measured based on an image of the lattice pattern in the captured image, wherein the three-dimensional image is captured by the line sensor. 2. A projection apparatus for projecting a grid pattern composed of a plurality of straight line patterns parallel to each other on an object to be measured, a line sensor for imaging the grid pattern projected on the object to be measured, A moving device that integrally moves a line sensor with respect to the measured object; and an arithmetic device that calculates a three-dimensional shape of the measured object based on a grid pattern image in an image captured by the line sensor. A three-dimensional measuring device comprising: 3. The three-dimensional measuring apparatus according to claim 2, wherein an extending direction of a linear pattern projected on the object to be measured and an extending direction of a linear imaging area of the line sensor on the object to be measured. A three-dimensional measuring device characterized in that the angle between the two is substantially zero. 4. The three-dimensional measuring apparatus according to claim 2, wherein an extending direction of a linear pattern projected on the object to be measured and an extending direction of a linear imaging area of the line sensor on the object to be measured. A three-dimensional measuring device provided with an angle changing device for changing an angle of the three-dimensional measuring device.