JPH08233520A - Three-dimensional shape measuring device - Google Patents

Abstract

(57) [Abstract] [Purpose] To measure the three-dimensional shape of a measured object with high accuracy, stably without being influenced by the inclination of the surface of the measured object. [Structure] The calculation / control unit 18 uses a slit-shaped irradiation light 1
A row of light receiving elements of the two-dimensional light receiving sensor of the light receiving section 15 arranged in a direction orthogonal to the direction corresponding to the spreading direction (Y direction) of 4a, and a plurality of light receiving elements belonging to the row in the output signal of the light receiving section 15 A control signal is sent to the irradiation unit drive circuit 17 based on the output signal of the two-dimensional light receiving sensor so that the number of columns in which the maximum level of the plurality of levels corresponding to each element falls within a predetermined range is increased. To adjust the brightness of the slit-shaped irradiation light 14a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional shape measuring apparatus for measuring the three-dimensional shape of an object to be measured by using an optical distance sensor using slit-shaped irradiation light.

[0002]

2. Description of the Related Art An optical distance sensor provided with an irradiating section for irradiating an object to be measured with irradiation light and a light receiving section for receiving reflected light from the object to be measured is used to non-contact the third order of the object to be measured. Conventionally, measuring the original shape has been widely performed. This method is widely known as a method that is simple and relatively good in accuracy, since it does not involve deformation of the object to be measured due to the contact pressure of the probe that is necessarily accompanied by measurement with the contact probe, correction of the radius of the contact sphere at the probe tip, etc. ing.

As one of such optical distance sensors, there is a triangulation type optical distance sensor which utilizes the principle of triangulation and uses slit-shaped irradiation light.

FIG. 4 is an explanatory view showing the measuring principle of such a triangulation type optical distance sensor 1.

As shown in FIG. 4, this optical distance sensor 1
Is irradiated from a slit-shaped irradiation light (in the example shown in FIG. 4, it spreads in a direction perpendicular to the paper surface in FIG. 4) to the DUT 6, and from the DUT 6. And a light receiving section 3 such as a CCD camera for receiving the reflected light. The light receiving unit 3 includes a two-dimensional light receiving sensor 4 such as a two-dimensional CCD having a plurality of two-dimensionally arranged light receiving elements, and reflected light from the object 6 to be measured by the irradiation light, that is, the measurement by the irradiation light. The light receiving lens 5 is configured to project an image (light cutting line) on the object 6 onto the light receiving surface of the two-dimensional light receiving sensor 4.

According to the optical distance sensor 1, the slit-shaped irradiation light emitted from the irradiation unit 2 is applied to the DUT 6, and the reflected light is received by the light receiving sensor 4 via the light receiving lens 5. At this time, as shown in FIG. 4, the position of the reflected light entering the light receiving sensor 4 changes according to the position of the surface of the DUT 6. Therefore, an output indicating the distance from the light receiving sensor 4 to each point on the light cutting line on the DUT 6 is collectively obtained.

In the conventional three-dimensional shape measuring apparatus using the optical distance sensor such as the laser displacement meter as described above, the slit-shaped irradiation light is always radiated at a constant brightness, and the optical distance sensor and the Based on the output of the optical distance sensor according to a plurality of predetermined relative positions between the optical distance sensor and the object to be measured while changing the relative position to the object to be measured, the three-dimensional shape of the object to be measured. I was preparing the data.

[0008]

However, in the above-described conventional three-dimensional shape measuring apparatus, when measuring the three-dimensional shape of the object to be measured, a portion (shape data) that cannot be measured due to the inclination of the surface of the object to be measured (shape data). In many cases) and in some cases the measurement accuracy was reduced.

This is because in the optical distance sensor as described above, the light receiving portion is determined by the relationship between the light irradiation direction and the light receiving direction of the reflected light from the object to be measured and the inclination of the surface of the measuring point of the object to be measured. This is because the amount of reflected light that enters the two-dimensional light receiving sensor changes significantly.

For example, when the optical distance sensor 1 shown in FIG. 4 is used, as shown in FIG. 4, the normal line of the surface of the DUT 6 with respect to the irradiation optical axis and the receiving optical axis of the optical distance sensor 1 is measured. When the inclination is small, the light receiving unit 3 of the optical distance sensor 1 receives a large amount of reflected light from the DUT 6.

On the other hand, as shown in FIG. 5, the optical distance sensor 1
When the normal line of the surface of the DUT 6 has a large inclination with respect to the irradiation optical axis and the received optical axis, the light receiving unit 3 of the optical distance sensor 1
Can receive only a small amount of reflected light from the DUT 6. Specifically, as shown in FIG. 5, when the light receiving unit 3 is located on the right side with respect to the irradiation unit 2 and the surface of the DUT 6 is largely inclined to the left side, the reflected light from the DUT 6 is reflected. Is almost to the left of the irradiation unit 2, and the light receiving unit 3 can receive only a small amount of reflected light.

If the amount of light received by the light receiving section 3 is reduced, the light is more likely to be affected by outside light, the so-called SN ratio is lowered, and the measurement accuracy is lowered. If the amount of received light is further reduced to a predetermined value or less, measurement becomes virtually impossible. On the other hand, if the light receiving amount of the light receiving unit 3 is too large, the output of the light receiving element of the two-dimensional light receiving sensor 4 of the light receiving unit 3 will be saturated, and the light cutting line projected on the two-dimensional light receiving sensor 4 of the light receiving unit 3. When performing the so-called sub-pixel processing for obtaining the center position of the image of, it becomes impossible to obtain the center position with high accuracy, therefore,
The measurement accuracy is also reduced.

The present invention has been made in view of such conventional problems, and stably measures the three-dimensional shape of an object to be measured with high accuracy without being influenced by the inclination of the surface of the object to be measured. An object is to provide a three-dimensional shape measuring device that can be used.

[0014]

In order to solve the above-mentioned problems, the three-dimensional shape measuring apparatus according to the first aspect of the present invention comprises:
An irradiation unit for irradiating an object to be measured with slit-shaped irradiation light and a light receiving unit having a two-dimensional light receiving sensor having a plurality of two-dimensionally arranged light receiving elements, the object to be measured by the irradiation light. An optical distance sensor including a light receiving unit that receives the upper image on the two-dimensional light receiving sensor, a position changing unit that changes a relative position between the optical distance sensor and the object to be measured, and the light. Three-dimensional shape data creating means for creating three-dimensional shape data of the object to be measured based on output signals of the two-dimensional light receiving sensor corresponding to a plurality of predetermined relative positions between the distance sensor and the object to be measured. In the three-dimensional shape measuring apparatus comprising: a row of light-receiving elements of the two-dimensional light-receiving sensor arranged in a direction orthogonal to a direction corresponding to a spreading direction of the slit-shaped irradiation light, Belongs to the column Based on the output signal of the two-dimensional light receiving sensor, the number of rows in which the maximum level among the plurality of levels corresponding to the plurality of light receiving elements falls within a predetermined range is increased. It further comprises adjusting means for adjusting the brightness.

A three-dimensional shape measuring apparatus according to a second aspect of the present invention has an irradiation section for irradiating an object to be measured with slit-shaped irradiation light, and a plurality of light receiving elements each two-dimensionally arranged. A plurality of light receiving portions each having a two-dimensional light receiving sensor, each light receiving portion receiving the image of the irradiation light on the object to be measured in different directions on the two-dimensional light receiving sensor. An optical distance sensor provided, position changing means for changing the relative position between the optical distance sensor and the object to be measured, at a predetermined plurality of relative positions between the optical distance sensor and the object to be measured. Three-dimensional shape measurement means for producing three-dimensional shape data of the object to be measured based on an output signal of at least one of the two-dimensional light receiving sensors of the plurality of light receiving units according to the three-dimensional shape measurement. In the device, the plurality of A row of light-receiving elements of the two-dimensional light-receiving sensor arranged in a direction orthogonal to a direction corresponding to the spread direction of the slit-shaped irradiation light with respect to at least one of the light-receiving units, and the row in the output signal. The irradiation based on the output signal of the two-dimensional light receiving sensor so that the number of columns in which the maximum level of the plurality of levels corresponding to the plurality of light receiving elements belonging to It further comprises adjusting means for adjusting the brightness of light.

[0016]

According to the present invention, the brightness of the irradiation light is optimized by the adjusting means, and the light receiving amount of many light receiving elements of the two-dimensional light receiving sensor is constant regardless of the inclination of the surface of the object to be measured. Kept in range. Therefore, according to the present invention, not only the number of unmeasurable points is reduced, but also the deterioration of measurement accuracy due to ambient light is reduced and the outputs of many light receiving elements of the two-dimensional light receiving sensor are not saturated, so that the two-dimensional light receiving is performed. The center position of the image of the light cutting line projected on the sensor 4 can be accurately obtained. Therefore, according to the present invention, it is possible to stably measure the three-dimensional shape of the measured object without being influenced by the inclination of the surface of the measured object.

In the first aspect of the present invention, the single light-receiving portion may be provided, whereas in the second aspect of the present invention, a plurality of light-receiving portions for receiving the light cutting lines from mutually different directions. Although they are different in that they are provided with parts, they are substantially the same.

However, as described above, the cause of the change in the quantity of the reflected light received is that the light irradiation direction and the light receiving direction of the reflected light from the measured object and the inclination of the surface of the measured point of the measured object. Therefore, the light receiving state of either one of the light receiving portions is better than the light receiving state of the other light receiving portion depending on the measurement location of the object to be measured. Therefore, if a plurality of light receiving units are used as in the second aspect, the output of the light receiving unit that is better depending on the light receiving state of each light receiving unit can be adopted as the measurement data, and a single light receiving unit can be used. Compared to using only
The measurement accuracy can be further improved.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A three-dimensional shape measuring apparatus according to various embodiments of the present invention will be described below with reference to the drawings. In addition,
In the following examples, the object to be measured is a dental work model. However, the object to be measured is not limited to this, and the three-dimensional shape measuring apparatus according to the present invention can measure any other object.

First, a three-dimensional shape measuring apparatus according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 is a diagram schematically showing the overall structure of a three-dimensional shape measuring apparatus according to the first embodiment of the present invention.

As shown in FIG. 1, the three-dimensional shape measuring apparatus according to the present embodiment has an X stage 11 mounted on a main body substrate (not shown) and movable in the X direction, and above the X stage 11. And an optical distance sensor 12 attached to the main body base. The device under test 13 is placed on the X stage 11. In this embodiment, the X stage 1
1 constitutes a position changing means for changing the relative position between the optical distance sensor 12 and the object to be measured 13.

Note that, in FIG. 1, in order to facilitate understanding of the movement of the X stage 11, the fixed portion of the X stage 11 is indicated by 11a, and the movable portion of the X stage 11 is indicated by 11b.

The optical distance sensor 12 has the same structure as the displacement meter 1 shown in FIG. That is, the optical distance sensor 12 irradiates the DUT 13 with the slit-shaped irradiation light 14a that spreads in the Y direction perpendicular to the X direction.
4 and a light receiving section 15 for receiving the reflected light from the DUT 13.
And have. Although not shown in the drawing, the light receiving unit 15 has a two-dimensional light receiving sensor such as a two-dimensional CCD having a plurality of two-dimensionally arranged light receiving elements.
For example, a CCD camera can be used as 5. Both the irradiation unit 14 and the light receiving unit 15 are fixed to the main body base.

In the three-dimensional shape measuring apparatus according to this embodiment, as shown in FIG. 1, a motor drive circuit 16 for driving a drive motor (not shown) of the X stage 11 and an irradiation section of the optical distance sensor 12. Irradiation unit drive circuit 17 for driving 14
And a calculation / control unit 18 that performs various calculations and controls, an input device 19 such as a keyboard for a measurer to give various commands to the calculation / control unit 18, and the position (or drive amount) of the X stage 11. And a position detector (not shown) such as an encoder for detecting.

The arithmetic / control unit 18 is composed of a microcomputer having a storage device, a CPU, etc. (not shown) built therein, and functions as a drive control unit for controlling the operation of the motor drive circuit 16 and the irradiation unit drive circuit 17, and The function as a three-dimensional shape data creating unit that creates three-dimensional shape data based on the output from the light receiving unit 15 of the optical distance sensor 12 and the output from the position detector (position detection signal of the X stage 11), and It performs various functions such as a function as a sub-pixel processing unit that performs sub-pixel processing.

In this embodiment, the three-dimensional shape data created by the arithmetic / control unit 18 is the CAD that uses this data.
It is adapted to be supplied to the device 20.

The subpixel processing performed by the arithmetic / control unit 18 will be described with reference to FIG.

When the measurement object 13 is irradiated with the slit-shaped irradiation light 14a from the irradiation section 14, a cutting line 13a is formed along the shape of the measurement object 13, and the cutting line 13a is imaged by the light receiving section 15. It That is, as shown in FIG. 2A, the image 21 of the cutting line 13a is projected on the light receiving surface of the two-dimensional light receiving sensor of the light receiving unit 15.

FIG. 2A is a view showing an image 21 of the cutting line 13a on the light receiving surface of the two-dimensional light receiving sensor of the light receiving section 15. The horizontal axis in FIG. 2A indicates the position on the light receiving surface in the Y1 direction corresponding to the Y direction in FIG. 1 (that is, the spreading direction of the slit-shaped irradiation light 14a). Figure 2
The vertical axis in (a) is Z perpendicular to the Y1 direction on the light receiving surface.
The position in one direction is shown. The thickness of the image 21 of the cutting line 13a is usually larger than the length of one light receiving element in the vertical direction (Z1 direction), and is, for example, about 10 elements.

At a certain position in the Y1 direction, the output level distribution of the two-dimensional light receiving sensor corresponding to one row of light receiving elements arranged in the Z1 direction (on the light receiving surface of the two-dimensional light receiving sensor, at a certain position in the Y1 direction, the Z1 direction (Corresponding to the distribution of the amount of received light) is as shown in FIG. The position in the Z1 direction of the image 21 of the cutting line 13a at this position in the Y1 direction corresponds to the position where the output level is large in FIG. 2B. It should be noted that D _MAX in FIG. 2B represents the maximum level of the output levels corresponding to one row of light receiving elements arranged in the Z1 direction at a certain position in the Y1 direction.

The process of estimating the center position in the Z1 direction of the image 21 of the cutting line 13a from the shape of the distribution as shown in FIG. 2B is what is called subpixel process. In particular,
For example, the center position in the Z1 direction of the image 21 of the cutting line 13a is set by using the weighted average of the portion having a predetermined threshold value D ₀ or more in FIG.

Since the center position of the image 21 of the cutting line 13a in the Z1 direction indicates the distance to the measurement point of the object to be measured 13 corresponding to the position in the Y1 direction, the calculation / control unit 18
As a part of the process of producing the three-dimensional shape data, the light receiving unit 15
The above-described sub-pixel processing is performed on the output signal of the two-dimensional light receiving sensor.

Next, an example of the operation of the three-dimensional shape measuring apparatus according to this embodiment will be described.

First, since the measurement points necessary for the measurement of the dental model as the object to be measured 13 are the intersecting surfaces and the side surfaces of the teeth, the measurer places the object to be measured so that the surface not to be measured is facing down. 13 is temporarily fixed to the X stage 11 with an adhesive (not shown).

In this state, the calculation / control section 18 gives a control signal to the irradiation section drive circuit 17 in response to the measurement start command given from the input device 19 by the measurer, and the irradiation section 1
The slit light 14a having a predetermined brightness is irradiated onto the DUT 13 from 4 to form a cutting line 13a along the shape of the DUT 13.

The cutting line 13a is imaged obliquely by the light receiving section 15. That is, as shown in FIG.
The image 21 of the cutting line 13a is projected on the light receiving surface of the two-dimensional light receiving sensor of the light receiving unit 15. As a result, an output signal corresponding to the image 21 is obtained from the two-dimensional light receiving sensor of the light receiving unit 15.

The calculation / control section 18 gives a control signal to the irradiation section drive circuit 17 based on the output of the two-dimensional light receiving sensor, and outputs a drive voltage to the irradiation section 14 via the irradiation section drive circuit 17. By adjusting, the brightness of the slit-shaped irradiation light 14a is adjusted.

That is, the calculation / control unit 18 sets Z corresponding to the spreading direction (Y direction) of the slit-shaped irradiation light 14a.
In the row of the light receiving elements of the two-dimensional light receiving sensor arranged in one direction, the maximum level of the plurality of levels corresponding to the plurality of light receiving elements belonging to the row in the output signal of the two-dimensional light receiving sensor is Predetermined range (Fig. 2 (b))
The slit-shaped irradiation light is increased based on the output signal of the two-dimensional light receiving sensor so that the number of columns falling within the range (D _{1 to} D ₂ ) is large (preferably, maximum). 1
Adjust the brightness of 4a.

For example, the two-dimensional light receiving sensor is 500
× 1000 light receiving elements (5 in the Y1 direction in FIG. 2 (a))
Assuming that 00 light receiving elements have 1000 light receiving elements in the Z1 direction, 1000 light receiving elements arranged in the Z1 direction are arranged.
This means that there are 500 rows of light receiving elements. In this case, the arithmetic / control unit 18 has the maximum level (see FIG. 2 (500) of the plurality of levels corresponding to 1000 light receiving elements belonging to the column in the output signal of the two-dimensional light receiving sensor in the 500 columns. 2) is equivalent to D _MAX in b).
The brightness of the slit-shaped irradiation light 14a is adjusted so that the number of rows included in the range of D _{1 to} D ₂ in (b) increases.

The specific adjustment can be performed by, for example, the above 500.
This can be done by obtaining the maximum level D _MAX of each of the columns and setting the brightness of the slit-shaped irradiation light 14a based on the distribution state of the level values of these 500 maximum levels D _MAX . If necessary, slit-shaped irradiation light 1
The luminance of 4a may be set to a plurality of known luminances, 500 maximum levels D _MAX are obtained according to the respective luminances, and the luminance of the slit-shaped irradiation light 14a may be set based on these.

If the light quantity of the image 21 of the cutting line 13a projected on the light receiving surface of the two-dimensional light receiving sensor is too large, the output obtained from the light receiving element will be saturated, and the cutting line 13a of the cutting line 13a will be saturated by the above-described sub-pixel processing. The accuracy in determining the center position of the image 21 decreases. On the contrary, if the light quantity becomes too small, the influence of ambient light becomes large, and the measurement accuracy also deteriorates. Therefore, the range D _{1 to} D ₂ is set in consideration of such a point. For example, the boundary D of this range
₂ is set to be slightly lower than the saturated output level of the light receiving element.

Incidentally, the cutting line 13a on the object to be measured 13
Since the inclination of the surface of each point is different, the cutting line 13a
The amount of light at each part of the image 21 is different. Therefore,
Even when the brightness is changed in the slit-shaped illumination light 14a, no guarantee that the output level of the light receiving portion 15 enters the range D ₁ to D ₂ over the entire length of the image 21 of the cutting line 13a. Therefore, as described above, the brightness of the slit-shaped irradiation light 14a is adjusted so that the number of rows is increased.

When the adjustment of the slit-shaped irradiation light 14a is completed, the calculation / control unit 18 once stores the image of the cutting line 13a obtained as the output of the two-dimensional light receiving sensor in a frame memory (not shown). The image data is stored and subjected to the above-described sub-pixel processing to find the center position of the image 21 of the cutting line 13a in the Z1 direction at each position in the Y1 direction, and the data is associated with the position data of the X stage. To a memory (not shown). with this,
The measurement for one cutting line 13a is completed.

To measure the entire object 12 to be measured, X
After moving the stage 11 at a predetermined pitch, the measurement may be repeated in the same procedure. If the entire area of the DUT 13 can be measured at a predetermined pitch, all the measurements are completed.

According to this embodiment, slit-shaped irradiation light 1
The luminance of 4a is optimized, and the light-receiving amounts of many light-receiving elements of the two-dimensional light-receiving sensor of the light-receiving unit 15 are kept within a fixed range regardless of the inclination of the surface of the DUT 13. Therefore, not only the number of unmeasurable points decreases, but also the deterioration of measurement accuracy due to ambient light decreases and the outputs of many light receiving elements of the two-dimensional light receiving sensor do not saturate.
The center position of the image of the light cutting line projected on the three-dimensional light receiving sensor can be accurately obtained. Therefore, the DUT 13
The three-dimensional shape of the DUT 13 can be stably measured with high accuracy regardless of the inclination of the surface.

Next, a three-dimensional shape measuring apparatus according to a second embodiment of the present invention will be described with reference to FIG.

FIG. 3 is a diagram showing the overall structure of a three-dimensional shape measuring apparatus according to the second embodiment of the present invention. 3, constituent elements that are the same as or correspond to the constituent elements in FIG. 1 are assigned the same reference numerals, and redundant description will be omitted.

This embodiment is different from the above-mentioned first embodiment in the following points.

That is, in the present embodiment, in the first embodiment, the light receiving portion 31 fixed to the main body base is arranged so as to have a symmetrical positional relationship with the light receiving portion 15 with respect to the slit-shaped irradiation light 14a. , Has been added. The light receiving unit 31 has the same structure as the optical distance sensor 15. The light receiving unit 31 does not necessarily have to be arranged symmetrically with the light receiving unit 15, and may be arranged so as to receive the image of the cutting line 13 a from a direction different from that of the light receiving unit 15.

An example of the operation of the three-dimensional shape measuring apparatus according to this embodiment will be described.

First, as in the first embodiment, the object to be measured 13 is temporarily fixed to the X stage 11.

In this state, the calculation / control section 18 gives a control signal to the irradiation section drive circuit 17 in the same manner as in the first embodiment, and the irradiation section 14 emits slit light 14a of a predetermined brightness to the object to be measured 13. Is irradiated to form a cutting line 13a along the shape of the DUT 13.

The cutting line 13a is obliquely imaged by the light receiving portions 15 and 31. That is, as shown in FIG. 2A, the cutting line 1 is formed on the light receiving surface of the two-dimensional light receiving sensor of the light receiving unit 15 and the light receiving surface of the two-dimensional light receiving sensor of the light receiving unit 31.
The images of 3a are projected respectively. As a result, output signals corresponding to those images are obtained from the two-dimensional light receiving sensor of the light receiving unit 15 and the two-dimensional light receiving sensor of the light receiving unit 31.

The calculation / control unit 18 determines the irradiation unit drive circuit 1 based on the outputs of the two-dimensional light receiving sensors of the light receiving units 15 and 31.
7 by giving a control signal to the irradiation section drive circuit 17,
The brightness of the slit-shaped irradiation light 14a is adjusted by adjusting the drive voltage or the like for the irradiation unit 14.

That is, the calculation / control unit 18 is the light receiving unit 1
A row of light receiving elements of a two-dimensional light receiving sensor arranged in a direction corresponding to a spreading direction (Y direction) of the slit-shaped irradiation light 14a for at least one of the two-dimensional light receiving sensors. In order to increase the number of columns in which the maximum level of the plurality of levels corresponding to the plurality of light receiving elements belonging to the column in the output signal falls within a predetermined range (preferably, the maximum level), The brightness of the slit-shaped irradiation light 14a is adjusted based on the output signal of the two-dimensional light receiving sensor.

For example, the calculation / control unit 18 first performs slit-shaped irradiation so that the number of rows in which the maximum level D _MAX falls within a predetermined range for the light-receiving unit 15 increases, as in the first embodiment. The brightness of the light 14a is adjusted. And
In the thus adjusted first luminance, the number of columns in which the maximum level D _MAX falls within a predetermined range is obtained for the light receiving unit 15. Next, similarly to the first embodiment, the brightness of the slit-shaped irradiation light 14a is adjusted so that the number of rows in which the maximum level D _MAX falls within the predetermined range is increased in the light receiving unit 31. Then, for the second luminance adjusted in this way, the number of columns in which the maximum level D _MAX falls within the predetermined range is obtained for the light receiving unit 31. The number of columns in which the maximum level D _MAX falls within a predetermined range for the light receiving unit 15 at the first luminance is compared with the number of columns in which the maximum level D _MAX falls within a predetermined range for the light receiving unit 31 at the second luminance. The brightness of the slit-shaped irradiation light 14a is set to the first or second brightness corresponding to the light receiving section having the larger number of rows.

When the adjustment of the slit-shaped irradiation light 14a is completed, the arithmetic / control unit 18 produces an image of the cutting line 13a obtained as the output of the two-dimensional light receiving sensor of the light receiving unit having the larger number of rows. Is temporarily stored in a frame memory (not shown), the above-described sub-pixel processing is performed on this image data, and the cutting line 13 is formed at each position in the Y1 direction.
The center position of the image 21 of a in the Z1 direction is obtained, and the data is stored in a memory (not shown) in association with the position data of the X stage. This completes the measurement for one cutting line 13a.

To measure the entire object 13 to be measured, X
After moving the stage 11 at a predetermined pitch, the measurement may be repeated in the same procedure. If the entire area of the DUT 13 can be measured at a predetermined pitch, all the measurements are completed.

Also in the present embodiment, similarly to the first embodiment, the stable measurement is performed without being influenced by the inclination of the surface of the object to be measured,
The three-dimensional shape of the measured object can be measured with high accuracy.

However, as described above, the cause of the change in the amount of the reflected light received is that the light irradiation direction and the light receiving direction of the reflected light from the object to be measured and the inclination of the surface of the measuring point of the object to be measured. Therefore, the light receiving state of either one of the light receiving portions is better than the light receiving state of the other light receiving portion depending on the measurement location of the object to be measured. Therefore, in the present embodiment, the output of the light receiving unit that is better depending on the light receiving state of each of the light receiving units 15 and 31 is adopted as the measurement data, and only the single light receiving unit 15 is used. Compared to the first embodiment,
The measurement accuracy can be further improved.

Although the respective embodiments of the present invention have been described above, the present invention is not limited to these embodiments.

For example, although a single optical distance sensor is used, a plurality of optical distance sensors may be used. Further, the number of light receiving parts in the optical distance sensor is not limited.

Further, in each of the above-described embodiments, the X stage 11 is adopted as the position changing means for changing the relative position between the optical distance sensor and the object to be measured, but the relative position is changed to a desired three-dimensional shape. If the position necessary for obtaining the position can be obtained, any structure can be adopted as the position changing means.

[0065]

As described above, according to the present invention,
It is possible to measure the three-dimensional shape of the measured object with high accuracy stably without being influenced by the inclination of the surface of the measured object.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an overall configuration of a three-dimensional shape measuring apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a light receiving state of a two-dimensional light receiving sensor of a light receiving unit.

FIG. 3 is a diagram schematically showing an overall configuration of a three-dimensional shape measuring apparatus according to a second embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a measurement principle of a triangulation type optical distance sensor using slit-shaped irradiation light.

FIG. 5 is an explanatory diagram showing a situation where the reflected light from the object to be measured is offset.

[Explanation of symbols]

 11 X stage 12 Optical distance sensor 13 Object to be measured 13a Cutting line 14 Irradiation unit 15, 31 Light receiving unit 16 Motor drive circuit 17 Irradiation unit drive circuit 18 Arithmetic / control unit 21 Image of cutting line

Claims (2)

[Claims] 1. A light-receiving unit having a two-dimensional light receiving sensor having a plurality of light-receiving elements arranged two-dimensionally, and an irradiation unit for irradiating an object to be measured with slit-shaped irradiation light. An optical distance sensor including a light receiving section for receiving an image on the object to be measured by the two-dimensional light receiving sensor according to the above, and a position change for changing a relative position between the optical distance sensor and the object to be measured. Means for producing three-dimensional shape data of the object to be measured based on output signals of the two-dimensional light receiving sensor according to a plurality of predetermined relative positions between the optical distance sensor and the object to be measured. A three-dimensional shape measuring apparatus comprising: original shape data generating means, wherein a row of light receiving elements of the two-dimensional light receiving sensor is arranged in a direction orthogonal to a direction corresponding to a spreading direction of the slit-shaped irradiation light. , In the output signal Based on the output signal of the two-dimensional light receiving sensor so that the number of rows in which the maximum level among the plurality of levels corresponding to the plurality of light receiving elements belonging to the row falls within a predetermined range, increases. A three-dimensional shape measuring apparatus further comprising adjusting means for adjusting the brightness of the irradiation light. 2. An irradiation section for irradiating an object to be measured with slit-shaped irradiation light, and a plurality of light receiving sections each having a two-dimensional light receiving sensor having a plurality of two-dimensionally arranged light receiving elements. And an optical distance sensor, each of which includes a plurality of light receiving portions that receive the image of the object to be measured by the irradiation light on the two-dimensional light receiving sensor in different directions from each other; Of the two-dimensional light receiving sensors of the plurality of light receiving units according to a plurality of predetermined relative positions between the optical distance sensor and the object to be measured, a position changing unit that changes a relative position to the object to be measured. A three-dimensional shape data creating unit that creates three-dimensional shape data of the object to be measured based on at least one output signal of Regarding one, before A plurality of rows of light-receiving elements of the two-dimensional light-receiving sensor arranged in a direction orthogonal to the direction corresponding to the spread direction of the slit-shaped irradiation light, each row corresponding to a plurality of light-receiving elements belonging to the row in the output signal. Based on the output signal of the two-dimensional light receiving sensor, the number of columns in which the maximum level of the
The three-dimensional shape measuring apparatus further comprising an adjusting unit that adjusts the brightness of the irradiation light.