JP5487920B2 - Optical three-dimensional shape measuring apparatus and optical three-dimensional shape measuring method - Google Patents

Description

  The present invention relates to an optical three-dimensional shape measuring device and an optical three-dimensional shape measuring method, and more particularly to an optical three-dimensional measuring device and a three-dimensional measuring method applicable to three-dimensional shape measurement of a glossy object surface. is there.

  For measuring the three-dimensional shape of an object, an optical three-dimensional measuring apparatus is often used industrially. Among them, the optical three-dimensional measuring apparatus based on the triangulation principle is balanced in terms of measurement range, measurement resolution, measurement time, reliability, and the like.

  As a three-dimensional measuring device for an object using the triangulation principle, for example, in Patent Document 1, slit light is projected onto a measurement target, and reflected light reflected from the target object is collected by a lens and detected by an image sensor. A shape measuring device is described.

  In Patent Document 2, the reflected light of the spot light irradiated from the light irradiation means onto the surface of the object to be measured is separated through a half mirror, and the center of gravity position of the received light intensity of the separated transmitted light is detected by the first light. The center of gravity of the received light intensity of the separated reflected light detected by the means is detected by the second light detecting means, and the object to be measured is measured from the predetermined measurement reference position based on the output signals of the first and second light detecting means. An optical shape meter provided with computing means for calculating the distance to is described.

  In Patent Document 3, in addition to the configuration described in Patent Document 2, a rotating mirror that uses spot-condensed light focused on the object to be measured and the object to be measured at a predetermined incident angle. Light irradiating means for irradiating, a secondary curved mirror for collecting and reflecting incident light reflected from the surface of the object to be measured, and a distance from a predetermined measurement reference position to the object to be measured as the rotating mirror. There is described an optical shape meter provided with a calculation means for calculating in synchronization with the rotation of.

  Further, as an image sensor that can be applied to an optical three-dimensional measurement apparatus in the future, Non-Patent Document 1 discloses a transparent image sensor configured by combining a polarization detection characteristic obtained by molecular optical anisotropy with a transparent electrode. (Transparent Image Sensor).

Japanese Patent Laid-Open No. 11-118443 JP-A-5-1904 Japanese Patent Laid-Open No. 5-60532

“Transparent Image Sensors Using an Organic Multilayer Photodiode”, H.C. Tanaka et al, Advanced Materials Volume 18, Issue 17, 2006, Pages 2230-2233

  In the shape measuring apparatus described in Patent Document 1, since reflected light forms an image at a corresponding position of the image sensor in accordance with the three-dimensional shape of the surface to be measured, reflection of the slit light on the object surface by the triangulation principle. The three-dimensional position of the point can be detected. The reflected light reflected from the measurement target is received while scanning the slit light on the measurement target, and the three-dimensional shape of the measurement target can be measured by the triangulation principle at each imaging position.

  However, in the detection of the three-dimensional position based on the triangulation principle described in Patent Document 1, it is assumed that the object to be measured has a matte surface. This is because, when the object to be measured is a matte surface, light is irregularly reflected on the surface of the object to be measured. Therefore, when the light is condensed by the lens and imaged on the image sensor, the light flux of the collected light is reflected. This is because, since the center always passes through the center of the lens, the triangulation principle can be applied regardless of the inclination of the object surface, and the reflection position of light on the object surface can be detected.

  However, when the object to be measured is a glossy surface such as a metal surface, the reflected light is not irregularly reflected on the surface of the object to be measured, and is regularly reflected while maintaining the shape of the light beam projected from the light source. The image is formed on the image sensor through the lens. In this case, if the object surface is exactly at the lens focal position, the specularly reflected light passes through the center of the lens. However, in such a case, the reflected light on the glossy surface does not necessarily pass through the center of the lens.

  Since the optical shape meter described in Patent Document 2 or Patent Document 3 calculates a distance from a predetermined measurement reference position to the surface of the object to be measured, the surface of the object to be measured is a mirror surface or a mirror surface. It is said that the shape, displacement or thickness of the measurement object can be stably and continuously measured in a non-contact manner even when the measurement object is tilted and halation occurs online in the near case. Yes. However, the optical shape meter described in Patent Document 2 or Patent Document 3 is an object that has a glossy surface such as a mirror surface from the viewpoint of (1) theoretical strictness and (2) restriction of application targets described below. It cannot be applied to dimension shape measurement.

(1) Theoretical rigor The optical shape meter described in Patent Document 2 or Patent Document 3 is described in paragraph [0024] of Patent Document 2 and paragraph [0046] of Patent Document 3 as “the surface of the object to be measured 11 is a mirror surface. Therefore, specular reflection of light occurs, and incident light is reflected at a reflection angle β ′ ”. Since regular reflection of light is assumed, Patent Document 2 and Patent Document 3 assume an incident angle β = reflection angle β ′. However, in an actual object, the incident angle = reflection angle is not strictly established. For this reason, the optical shape meter described in Patent Document 2 or Patent Document 3 that assumes the incident angle β = the reflection angle β ′ causes a theoretical error in an actual object having a different incident angle and reflection angle.

(2) Restriction of application target The optical shape meter described in Patent Document 2 or Patent Document 3 is “performs a planar geometric analysis in paragraph [0030] of Patent Document 2 and paragraph [0036] of Patent Document 3; As described in the above, it can be applied only to an object to be measured that satisfies this assumption. That is, the optical shape meter described in Patent Document 2 or Patent Document 3 considers only a one-dimensional inclination, and the application target is limited to a range where the assumption is acceptable.

  Thus, the conventional optical measuring device based on the triangulation principle has a problem that it is difficult to apply to the three-dimensional shape measurement of an object having a glossy surface such as a mirror surface.

  In view of the above problems, the present invention provides an optical three-dimensional shape measuring apparatus and an optical type 3 for realizing optical three-dimensional shape measurement of an object having not only a non-glossy surface but also a glossy surface such as a mirror surface. An object is to provide a dimension shape measuring method.

In order to achieve the above object, the present invention provides:
A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An irradiation surface position calculating means for calculating a position,
The light incident vector detection means includes an optical system including a lens that collects the reflected light and at least two image sensors.
The two image sensors are arranged such that the sensor surfaces are perpendicular to the optical axis of the lens or an axis in a direction divided from the optical axis, and at different distances from the light irradiation surface,
The irradiation surface position calculating means derives an incident vector to the two image sensors from a light receiving position of the two image sensors and a geometric condition of the optical system by three-dimensional vector analysis, An optical three-dimensional shape measuring apparatus is provided that calculates a three-dimensional position of the light irradiation surface by deriving a reflection position vector of the light beam.

The present invention also provides:
A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An irradiation surface position calculating means for calculating a position,
The light incident vector detecting means includes a lens that collects the reflected light, a half mirror that divides the reflected light in two directions, and two image sensors, a first image sensor and a second image sensor,
The lens is arranged such that one end surface side faces the measurement object,
The half mirror is disposed on the other end surface side of the lens and tilted by 45 degrees with respect to the optical axis of the lens so that the center coincides with the optical axis of the lens.
The first image sensor is arranged on an axis connecting the optical axis of the lens and the center of the half mirror so that a sensor surface is perpendicular to the axis,
The second image sensor is on an axis perpendicular to an axis connecting the optical axis of the lens and the center of the half mirror and in a direction in which the half mirror is inclined with respect to the lens. Are arranged so that the sensor surface is vertical,
The distance between the half mirror center and the first image sensor is different from the distance between the half mirror center and the second image sensor ,
The irradiation surface position calculation means calculates a vector of the reflected light by a three-dimensional vector analysis from a light receiving position of the two image sensors and a geometric condition of the optical system, and calculates a three-dimensional position of the light irradiation surface. An optical three-dimensional shape measuring apparatus is provided.

The present invention also provides:
A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An irradiation surface position calculating means for calculating a position,
The light incident vector detection means includes a half mirror that divides the reflected light into two directions of first reflected light and second reflected light, a first lens that collects the first reflected light, and the second reflected light. A second lens that collects the first reflected light, a first image sensor that receives the first reflected light, and a second image sensor that receives the second reflected light,
The half mirror is arranged to be inclined with respect to the measurement object,
The first lens is disposed on an axis connecting the measurement object and the half mirror so that one end surface side is perpendicular to the axis, and the first image sensor is connected to the other end surface side of the first lens. It is arranged so that the sensor surfaces are parallel,
The second lens is on an axis perpendicular to an axis connecting the measurement object and the center of the half mirror, and the half mirror is inclined with respect to the measurement object with respect to the axis. And the second image sensor is arranged such that the other lens surface of the second lens and the sensor surface are parallel to each other.
The distance between the half mirror center and the first lens and the distance between the half mirror center and the second lens are the same distance,
The distance between the first lens and the first image sensor is different from the distance between the second lens and the second image sensor ,
The irradiation surface position calculation means calculates a vector of the reflected light by a three-dimensional vector analysis from a light receiving position of the two image sensors and a geometric condition of the optical system, and calculates a three-dimensional position of the light irradiation surface. An optical three-dimensional shape measuring apparatus is provided.

The present invention also provides:
A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An irradiation surface position calculating means for calculating a position,
The light incident vector detection means includes a transmission sensor that transmits the reflected light, and an image sensor that receives the transmitted light transmitted through the transmission sensor.
The transmission sensor is arranged so that a sensor surface faces the measurement object,
The image sensor is arranged in parallel with the transmission sensor ,
The irradiation surface position calculation means calculates a vector of the reflected light by a three-dimensional vector analysis from a light receiving position of the two image sensors and a geometric condition of the optical system, and calculates a three-dimensional position of the light irradiation surface. An optical three-dimensional shape measuring apparatus is provided.

  Further, the present invention provides an optical three-dimensional shape measuring apparatus comprising a light beam scanning means for scanning a light beam from the light source on the surface of the measurement object.

In order to achieve the above object, the present invention provides:
A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An optical three-dimensional shape measuring method using an optical three-dimensional shape measuring device comprising an irradiation surface position calculating means for calculating a position,
The light incident vector detection means includes an optical system including a lens that collects the reflected light and at least two image sensors.
The two image sensors are arranged such that the sensor surfaces are perpendicular to the optical axis of the lens or an axis in a direction divided from the optical axis, and at different distances from the light irradiation surface,
The irradiation surface position calculating means derives an incident vector to the two image sensors from a light receiving position of the two image sensors and a geometric condition of the optical system by three-dimensional vector analysis, An optical three-dimensional shape measuring method is provided, wherein a three-dimensional position of the light irradiation surface is calculated by deriving a reflection position vector of the light beam.

  In addition, the present invention provides an optical three-dimensional shape measurement method characterized by measuring a three-dimensional shape of a measurement object by scanning a light beam from the light source on the surface of the measurement object.

  According to the present invention, an optical three-dimensional shape measuring apparatus and an optical three-dimensional shape measuring method for realizing an optical three-dimensional shape measurement of an object having not only a non-glossy surface but also a glossy surface such as a mirror surface. Is obtained.

It is a figure which shows the structure of the optical three-dimensional shape measuring apparatus which concerns on embodiment of this invention. It is a figure which shows the coordinate system of the optical three-dimensional shape measuring apparatus which concerns on embodiment of this invention. It is a figure which shows the coordinate system of a half mirror periphery with which the optical three-dimensional shape measuring device which concerns on embodiment of this invention is provided. It is a figure which shows the coordinate system of the lens periphery with which the optical three-dimensional shape measuring device which concerns on embodiment of this invention is provided. It is a figure which shows the coordinate system of the lens periphery with which the optical three-dimensional shape measuring device which concerns on embodiment of this invention is provided. It is a figure which shows the coordinate system around the light irradiation surface in the measuring object of the optical three-dimensional shape measuring apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the optical three-dimensional shape measuring apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows the coordinate system of the optical three-dimensional shape measuring apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows the coordinate system of a half mirror periphery with which the optical three-dimensional shape measuring device which concerns on the 2nd Embodiment of this invention is provided. It is a figure which shows the structure of the optical three-dimensional shape measuring apparatus which concerns on the 3rd Embodiment of this invention. It is a figure which shows the coordinate system of the optical three-dimensional shape measuring device which concerns on the 3rd Embodiment of this invention. It is a figure which shows the structure of the optical three-dimensional shape measuring apparatus which concerns on the 4th Embodiment of this invention. It is a figure which shows the structure of the optical three-dimensional shape measuring device which concerns on the 5th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 shows a configuration of an optical three-dimensional shape measuring apparatus according to an embodiment of the present invention. An optical three-dimensional shape measuring apparatus 1 shown in FIG. 1 includes a light incident vector detecting unit 2, an irradiation surface position calculating unit 3, and a light source 4. In the present embodiment, the calculator 33 is used as the irradiation surface position calculating means.

  The light incident vector detection means 2 includes a lens 23, a half mirror 24, a first image sensor 25a that is an image sensor 25, and a second image sensor 25b that is an image sensor 25.

  The lens 23 is arranged so that one end surface side faces the measurement object 6. The half mirror 24 is arranged on the other end surface side of the lens 23, that is, on the surface side opposite to the surface facing the measurement object 6. At this time, the half mirror 24 is disposed with an inclination of 45 degrees with respect to the optical axis so that the center thereof coincides with the optical axis of the lens 23.

  A first image sensor 25 a is disposed on an axis connecting the optical axis of the lens 23 and the half mirror 24 so that the sensor surface is perpendicular to the axis. The second image sensor 25b is on the axis perpendicular to the axis connecting the optical axis of the lens 23 and the half mirror 24, and the half mirror 24 is inclined with respect to the lens 23 with respect to the axis. The second image sensor 25b is arranged so that the sensor surface is vertical. The first image sensor 25a and the second image sensor 25b thus arranged are arranged such that the distances from the center of the half mirror 24 are different from each other.

  In the present embodiment, for example, a CCD camera or a PSD camera is preferably used for the first image sensor 25a and the second image sensor 25b.

  The first image sensor 25 a and the second image sensor 25 b are each connected to a calculator 33 that is the irradiation surface position calculation means 3. The computing unit 33 reversely traces the locus of the reflected light 7 by a three-dimensional vector analysis from the light receiving position information of the first image sensor 25a and the second image sensor 25b by a method described later.

  The light beam 5 irradiated from the light source 4 toward the measurement object 6 is reflected by the light irradiation surface 55 on the surface of the measurement object 6, and the reflected light 7 enters the lens 23 constituting the light incident vector detection means 2.

  The reflected light 7 incident on the lens 23 enters the half mirror 24 after passing through the lens 23. The reflected light 7 incident on the half mirror 24 is divided in two directions by the half mirror 24, one is received by the first image sensor 25a, and the other is received by the second image sensor 25b.

(3D vector analysis of the locus of reflected light 7)
(1) Coordinate system of optical three-dimensional shape measuring apparatus 1 according to the present embodiment In the present embodiment, the reflected light is reflected from the light receiving positions of the two image sensors, the first image sensor 25a and the second image sensor 25b. 7, that is, the incident vector u ₁ shown in FIG. 2 is obtained.

FIG. 2 shows a coordinate system of the optical three-dimensional shape measuring apparatus 1 according to the present embodiment. In the coordinate system shown in FIG. 2, the coordinate origin is the center of the lens 23. The P ₁ point on the measurement object 6 is a light irradiation surface 55 on which the light beam 5 is irradiated on the measurement object 6, and the P ₁ point is a value obtained by this analysis. P ₀ is a position vector of the light source 4, and L is a light projection vector of the light source 4.

Based these values and the values of P ₄ and P ₅ is a measure of the light receiving position vector of the reflected light 7 in the first image sensor 25a and the second image sensor 25b, obtains the P _1.

The positional relationship among the lens 23, the half mirror 24, the first image sensor 25a, and the second image sensor 25b is as follows.
Position vector of half mirror 24 center ... h
Distance between the half mirror 24 and the first image sensor 25a... D ₁
Distance between the half mirror 24 and the second image sensor 25b... D ₂
Distance between lens 23 and half mirror 24 ... d ₃

The aperture of the lens 23 is rd, and the lens thickness is d. Further, u ₁ , u ₂ , and u ₃ are unknown quantities generated in the middle of the calculation, and are respectively a reflection vector from the surface of the measurement object 6, a light beam vector of the reflected light 7 inside the lens 23, and a light beam of the reflected light 7. The incident vectors to the image sensors 25a and 25b are shown.

(2) Derivation of the incidence vector u ₃ to the image sensors 25a and 25b FIG. 3 shows a coordinate system around the half mirror 24 provided in the optical three-dimensional shape measuring apparatus 1 according to the present embodiment. In the present embodiment, as shown in FIG. 3, the positional relationship between the half mirror 24, the first image sensor 25a, and the second image sensor 25b, and the half mirror 24 is inclined 45 degrees with respect to the optical axis of the lens 23. Therefore, u ₃ can be obtained as follows from P ₅ ′ in the positional relationship between P ₄ and P ₅ and a mirror image.

Now, each component of h, P ₄ , and P ₅ that is a known amount is represented by h = (h _x , h _y , h _z ) (1)
P ₄ = (P _4x , P _4y , P _4z ) (2)
P ₅ = (P _5x , P _5y , P _5z ) (3)
Then, the x component and the z component of the vector u ₃ are u _3x = P _5x '-P _4x = d ₁ -d ₂ (4)
_u3z = _P5z' - _P4z = _{P5z- P4z} (5)
Here, since the half mirror 24 is installed perpendicular to the xy plane, the z coordinate system utilizes the fact that the position is invariable even if it is in a mirror image relationship.

On the other hand, the y component of u ₃ is obtained as follows.
a = p _5x -h _x (6)
b = a (7)
_{c = P 4x -h y (8} )
_{u 3y = b-c = P} 5x -h x - (P 4x -h y) (9)

Thus, the vector u ₃ is obtained as shown in equation (10).

(3) Derivation of intersection vector P ₃ of lens 23 Generally, the focal length f of the lens, the refractive index n _d of the lens material, the refractive index n of air, the lens aperture (radius) r _d , and the lens thickness d , The center of curvature C of the lens and the radius of curvature R of the lens are obtained as follows.

At this time, referring to the coordinate system around the lens 23 shown in FIG. 4, since P ₃ is on the spherical surface of the lens 23 and u ₃ starting from P ₄ , the following expression is satisfied. Here, P ₄ , u ₃ , and C ₂ represent vectors.
(P ₃ -C ₂ ) (P ₃ -C ₂ ) = R ² (13)
P ₃ = P ₄ + t · u ₃ (14)

(13), by calculating the t from equation (14), _{P 3} is determined by the following equation.

(4) Derivation of ray vector u ₂ in lens 23 Referring to FIG. 4, u ₂ is obtained from the refraction formula as follows.

Here, n _d and n represent the refractive index of glass and the refractive index of air, respectively. C ₂ represents the center of curvature of the lens 23, e ₂ is the normal vector at the point P _3, can be obtained by the following equation.

(5) Derivation of the ray vector u _{2 in} the lens 23 The intersection vector P ₂ of the lens 23 refers to the coordinate system shown in FIG.
(P ₂ -C ₁ ) (P ₂ -C ₁ ) = R ² (18)
P ₂ = P ₃ + s · u ₂ (19)
S is calculated from the equations (18) and (19), and P ₂ is obtained by the following equation. Here, C ₁ and u ₂ are vectors.

(6) light vector u ₁ of the reflected light 7 from the derived measurement object 6 light vectors u ₁ of the reflected light 7 from the measurement object 6, using the similar to the case, the expression of refraction (4) Obtained by the following formula.

ここで、ｅ_１は点Ｐ２における法線ベクトルであり、以下の式で求めることができる。

Here, e ₁ is the normal vector at the point P2, it can be obtained by the following equation.

(7) shows the derivation Figure 6 of the reflection position vector P ₁ of the light beam on the measurement object 6, the measuring light irradiation surface 55 in the object 6 (= vector P ₁ point) near the coordinate system, the below P ₁ Simultaneous equations hold.
P ₁ = P ₀ + s · L (23)
P ₁ = P ₂ + t · u ₁ (24)

P ₁ can be obtained by calculating s and t for each component of P ₀ , L, and P ₂ as follows.
P ₀ = (P _0x , P _0y , P _0z ) (25)
L = (L _x , L _y , L _z ) (26)
P ₂ = (P _2x , P _2y , P _2z ) (27)

(Effect of this embodiment)
Thus, in the present embodiment, the light receiving position of the two image sensors of the first image sensor 25a and the second image sensor 25b, the incident vector of the reflected light 7, that is, the incident vector u ₁ is determined. Then, based on u _1, reflecting the position vector P ₁ of the light beam on the measurement object 6 is derived.

  This removes the restrictions on the shape that can be applied to optical three-dimensional shape measurement using the triangulation principle, whether the surface reflection characteristics of the measurement object (irregular reflection surface (matte surface), glossy surface such as a mirror surface, etc.) ) And the theoretical error that occurs when calculating the optical three-dimensional shape is eliminated, and the optical three-dimensional shape measurement of an object having a glossy surface such as a mirror surface can be realized.

[Second Embodiment]
FIG. 7 shows the configuration of an optical three-dimensional shape measuring apparatus according to the second embodiment of the present invention. Since the optical three-dimensional shape measuring apparatus 11 shown in FIG. 7 is common to the optical three-dimensional shape measuring apparatus 1 shown in FIG. 1 except for the configuration of the light incident vector detecting means 12, the common components will be described. Is omitted.

  The light incident vector detecting means 12 shown in FIG. 7 includes a half mirror 24, a first lens 23a that is a lens 23, a second lens 23b that is a lens 23, and a first lens that is an image sensor 25. The image sensor 25 a and the second image sensor 25 b which is the image sensor 25 are configured.

  The half mirror 24 is disposed with an inclination of 45 degrees with respect to the optical axis of the first lens 23a.

  The first lens 23 a is disposed on an axis connecting the measurement object 6 and the center of the half mirror 24 so that one end surface side is perpendicular to the axis. The second lens 23b is on the axis perpendicular to the axis connecting the measurement object 6 and the center of the half mirror 24, and the half mirror 24 is inclined with respect to the optical axis of the first lens 23a. The one end surface side is arranged perpendicular to the axis.

  The first lens 23 a and the second lens 23 b arranged in this way are arranged so that the distance from the center of the half mirror 24 is the same.

  The first image sensor 25a is disposed on the other end surface side of the first lens 23a so that the sensor surface is parallel to the first lens 23a. The second image sensor 25b is arranged on the other end surface side of the second lens 23b so that the sensor surface is parallel to the second lens 23b.

  The first image sensor 25a and the second image sensor 25b arranged in this way have a distance between the first image sensor 25a and the first lens 23a and a distance between the second image sensor 25b and the second lens 23b. They are arranged at different distances.

  The light beam 5 irradiated from the light source 4 toward the measurement object 6 is reflected by the light irradiation surface 55 on the surface of the measurement object 6, and the reflected light 7 enters the half mirror 24 constituting the light incident vector detection means 12. .

  The reflected light 7 incident on the half mirror 24 is divided in two directions by the half mirror 24, one of which is transmitted through the first lens 23a and received by the first image sensor 25a, and the other is transmitted through the second lens 23b. Light is received by the second image sensor 25b.

(3D vector analysis of the locus of reflected light 7)
(1) Coordinate system of optical three-dimensional shape measuring apparatus 11 according to the present embodiment FIG. 8 shows a coordinate system of optical three-dimensional shape measuring apparatus 11 according to the present embodiment. In the coordinate system shown in FIG. 8, the coordinate origin is the center of the first lens 23a. Since the parameters are basically the same as those in the first embodiment, only different points will be described.

The positional relationship among the half mirror 24, the first lens 23a, the second lens 23b, the first image sensor 25a, and the second image sensor 25b is as follows. The position vector of the center of the half mirror 24 h, the distance between the first lens 23a and the first image sensor 25a _{d 1,} the distance between the second lens 23b and the second image sensor 25b _{d 2,} a half mirror 24 and the lens 23a, the distance between 23b respectively and _{d 3.} The apertures (radius) and lens thicknesses of the two lenses 23a and 23b are r _d and d, respectively.

(2) Derivation of the incidence vector u ₃ to the image sensors 25a and 25b FIG. 9 shows a coordinate system around the half mirror 24 provided in the optical three-dimensional shape measuring apparatus 11 according to the present embodiment. In the present embodiment, u ₃ is the first embodiment because of the positional relationship among the half mirror 24, the first lens 23a, the second lens 23b, the first image sensor 25a, and the second image sensor 25b shown in FIG. Can be obtained in exactly the same way.

That is, the x component and the z component of the vector u ₃ are respectively
u _3x = P _5x '-P _4x = d ₁ -d ₂ (29)
_u3z = _P5z' - _P4z = _{P5z- P4z} (30)

On the other hand, the y component of u ₃ is also determined as follows, as in the first embodiment.
a = p _5x -h _x (31)
b = a (32)
_{c = P 4x -h y (33} )
_{u 3y = b-c = P} 5x -h x - (P 4x -h y) (34)
Therefore, the vector u ₃ is obtained by the equation (35) as in the first embodiment.

(3) Derivation of the reflection position vector P ₁ of the light beam on the measurement object 6 Also in the case of the optical three-dimensional shape measuring apparatus 11 according to the second embodiment, the reflection position vector P of the light beam on the measurement object 6. _{Since 1} is an intersection of the vector u ₁ passing through the first lens 23a and the direction vector L from the light source 4, the reflection position vector P ₁ is exactly the same as that in the first embodiment.

Thus, also in this embodiment, the light receiving position of the two image sensors of the first image sensor 25a and the second image sensor 25b, the incident vector of the reflected light 7, that is, the incident vector u ₁ is determined. Then, based on u _1, reflecting the position vector P ₁ of the light beam on the measurement object 6 is derived.

  This removes the restrictions on the shape that can be applied to optical three-dimensional shape measurement using the triangulation principle, and the restrictions on the surface reflection characteristics of the measurement object (whether it is a diffuse reflection surface or a glossy surface such as a mirror surface). In addition, the theoretical error that occurs when calculating the optical three-dimensional shape is eliminated, and the optical three-dimensional shape measurement of an object having a glossy surface such as a mirror surface can be realized.

[Third Embodiment]
FIG. 10 shows the configuration of an optical three-dimensional shape measuring apparatus according to the third embodiment of the present invention. Since the optical three-dimensional shape measuring apparatus 21 shown in FIG. 10 is common to the optical three-dimensional shape measuring apparatus 1 shown in FIG. 1 except for the configuration of the light incident vector detecting means 22, the common constituent members will be described. Is omitted.

  The light incident vector detection means 22 shown in FIG. 10 includes a lens 23, a transmission sensor 26, and an image sensor 25.

  As the transmission sensor 26 in the present embodiment, for example, a sensor that can detect a light receiving position while transmitting light, such as a transparent image sensor described in Non-Patent Document 1, can be used.

  The lens 23 is arranged so that one end surface side faces the measurement object 6.

  A transmission sensor 26 is disposed on the other end surface side of the lens 23 on the axis line connecting the measurement target 6 and the optical axis of the lens 23 so that the sensor surface is perpendicular to the axis line. The image sensor 25 is arranged on the axis parallel to the transmission sensor so that the sensor surface of the image sensor 25 is perpendicular to the axis.

  The light beam 5 irradiated from the light source 4 toward the measurement object 6 is reflected by the light irradiation surface 55 on the surface of the measurement object 6, and the reflected light 7 enters the lens 23 constituting the light incident vector detection means 2.

  The reflected light 7 that has entered the lens 23 enters the transmission sensor 26 after passing through the lens 23. The reflected light 7 incident on the transmission sensor 26 passes through the transmission sensor 26 while being received by the transmission sensor 26 and is received by the image sensor 25. At this time, for example, when the transparent image sensor described in Non-Patent Document 1 is used as the transmission sensor 26, the reflected light 7 incident on the transmission sensor 26 is polarized by the transmission sensor 26, thereby forming a transparent image sensor that is the transmission sensor 26. A very small amount of photocurrent is detected by the photodiode. The position at which the transmission sensor 26 receives the reflected light 7 can be detected by the photocurrent detected by the photodiode.

(3D vector analysis of the locus of reflected light 7)
(1) Coordinate system of optical three-dimensional shape measuring apparatus 21 according to the present embodiment FIG. 11 shows a coordinate system of optical three-dimensional shape measuring apparatus 21 according to the present embodiment. In the coordinate system shown in FIG. 11, the coordinate origin is the center of the first lens 23. Since the parameters are basically the same as those in the first embodiment, only different points will be described.

The positional relationship among the lens 23, the transmission sensor 26, and the image sensor 25 is as follows. The distance between the lens 23 and the transmission sensor 26 is d ₁ , and the distance between the lens 23 and the image sensor 25 is d ₂ . The lens diameter and lens thickness of the lens 23 are r _d and d, respectively.

(2) Derivation of the incidence vector u ₃ to the transmission sensor 26 and the image sensor 26 In the present embodiment, u ₃ is the first value based on the positional relationship of the lens 23, the transmission sensor 26, and the image sensor 25 shown in FIG. It can be obtained in the same manner as in the embodiment.

That is, the x component and the z component of the vector u ₃ are respectively
u _3x = P _5x -P _4x = d ₁ -d ₂ (37)
_{u 3z = P 5z -P 4z =} P 5z -P 4z (38)

On the other hand, the y component of u ₃ is also determined as follows, as in the first embodiment.
a = p _5x (39)
b = a (40)
c = P _4x (41)
_{u 3y = b-c = P} 5x -P 4x (42)
Therefore, the vector u ₃ is obtained by the equation (43) as in the first embodiment.

(3) Derivation of the reflection position vector P ₁ of the light beam on the measurement object 6 Also in the case of the optical three-dimensional shape measuring apparatus 21 according to the third embodiment, the reflection position vector P of the light beam on the measurement object 6. _{Since 1} is an intersection of the vector u ₁ passing through the lens 23 and the direction vector L from the light source 4, the reflection position vector P ₁ is exactly the same as that in the first embodiment.

As described above, also in the present embodiment, the incident vector of the reflected light 7, that is, the incident vector u ₁ is obtained from the light receiving positions of the two image sensors of the transmission sensor 26 and the image sensor 25. Then, based on u _1, reflecting the position vector P ₁ of the light beam on the measurement object 6 is derived.

  This removes the restrictions on the shape that can be applied to optical three-dimensional shape measurement using the triangulation principle, whether the surface reflection characteristics of the measurement object (irregular reflection surface (matte surface), glossy surface such as a mirror surface, etc.) ) And the theoretical error that occurs when calculating the optical three-dimensional shape is removed, and the optical three-dimensional shape measurement of an object having a glossy surface such as a mirror surface can be realized.

[Fourth Embodiment]
An optical three-dimensional shape measuring apparatus according to the fourth embodiment of the present invention is shown in FIG. An optical three-dimensional shape measuring apparatus 31 shown in FIG. 12 is obtained by adding a light beam scanning means to the configuration of the optical three-dimensional shape measuring apparatus 1 according to the first embodiment of the present invention shown in FIG. Therefore, description of members common to the optical three-dimensional shape measuring apparatus 1 shown in FIG. 1 is omitted.

  An optical three-dimensional shape measuring apparatus 31 shown in FIG. 12 has a configuration of the optical three-dimensional shape measuring apparatus 1 according to the first embodiment of the invention shown in FIG. A control robot 83 and a rotary stage 84 are added. In the present embodiment, a capture board 34 is used in place of the calculator 33 used in the configuration of the optical three-dimensional shape measuring apparatus 1.

  The light source 4 is attached to the arm portion of the 6-axis control robot 83. The 6-axis control robot 83 is connected to the PC 81 via the controller 82 and is controlled by the PC 81.

  The light incident vector detection means 2 including the lens 23, the half mirror 24, the first image sensor 25a, and the second image sensor 25b is disposed on the rotary stage 84. The rotary stage 84 is connected to the PC 81 via the controller 82 and is controlled by the PC 81.

  The first image sensor 25 a and the second image sensor 25 b are connected to the capture board 34, and the capture board 34 is connected to the PC 81. With this configuration, the light reception information detected by the first image sensor 25a and the second image sensor 25b is transmitted to the PC 81 via the capture board 34, and three-dimensional vector analysis is performed by the PC 81. That is, in the present embodiment, the capture board 34 and the PC 81 constitute the irradiation surface position calculation means 3.

  Under the control of the PC 81, the six-axis control robot 83 is operated by the controller 82 so that the light beam 5 emitted from the light source 4 attached to the arm portion scans the surface of the measurement object 6. At the same time, the rotary stage 84 is rotated by the controller 82 under the control of the PC 81 so that the reflected light 7 from the measurement object 6 enters the lens 23. That is, in the present embodiment, the beam scanning means 8 is configured by the PC 81, the controller 82, the six-axis control robot 83, and the rotary stage 84.

  In the present embodiment, with the above-described configuration, the light beam 5 from the light source 4 is scanned on the surface of the measurement object 6, and the three-dimensional shape of the measurement object 6 can be measured.

[Modification of Fourth Embodiment]
FIG. 13 shows an optical three-dimensional shape measuring apparatus according to a modification of the fourth embodiment of the present invention. An optical three-dimensional shape measuring apparatus 41 shown in FIG. 13 is obtained by adding a light beam scanning means 8 to the configuration of the optical three-dimensional shape measuring apparatus 11 according to the second embodiment of the present invention shown in FIG. .

  The optical three-dimensional shape measuring apparatus 41 is the same as the optical three-dimensional shape measuring apparatus 31 shown in FIG. 12 except that the light incident vector detecting means 12 is provided.

  Also in the present embodiment, under the control of the PC 81, the 6-axis control robot 83 is operated by the controller 82 so that the light beam 5 emitted from the light source 4 attached to the arm portion scans the surface of the measurement object 6. Is done. At the same time, the rotary stage 84 is rotated by the controller 82 under the control of the PC 81 so that the reflected light 7 from the measurement object 6 enters the lens 23. That is, in the present embodiment, the beam scanning means 8 is configured by the PC 81, the controller 82, the six-axis control robot 83, and the rotary stage 84.

  In the present embodiment, with the above-described configuration, the light beam 5 from the light source 4 is scanned on the surface of the measurement object 6 and the three-dimensional shape of the measurement object 6 can be measured.

  DESCRIPTION OF SYMBOLS 1,11,21,31,41 ... Optical three-dimensional shape measuring device, 2, 12, 22, 32 ... Light incident vector detection means, 3 ... Irradiation surface position calculation means, 4 ... Light source, 5 ... Light, 6 ... Measurement object, 7 ... reflected light, 8 ... light beam scanning means, 23 ... lens, 24 ... half mirror, 25 ... image sensor, 26 ... transmission sensor, 33 ... calculator, 34 ... capture board, 55 ... light irradiation surface, 81 ... PC, 82 ... controller, 83 ... 6-axis control robot, 84 ... rotary stage.

Claims (7)

A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An irradiation surface position calculating means for calculating a position,
The light incident vector detection means includes an optical system including a lens that collects the reflected light and at least two image sensors.
The two image sensors are arranged such that the sensor surfaces are perpendicular to the optical axis of the lens or an axis in a direction divided from the optical axis, and at different distances from the light irradiation surface,
The irradiation surface position calculating means derives an incident vector to the two image sensors from a light receiving position of the two image sensors and a geometric condition of the optical system by three-dimensional vector analysis, A three-dimensional position of the light irradiation surface is calculated by deriving a reflection position vector of the light beam of the optical three-dimensional shape measuring apparatus. The light incident vector detecting means includes a lens that collects the reflected light, a half mirror that divides the reflected light in two directions, and two image sensors, a first image sensor and a second image sensor,
The lens is arranged such that one end surface side faces the measurement object,
The half mirror is disposed on the other end surface side of the lens and tilted by 45 degrees with respect to the optical axis of the lens so that the center coincides with the optical axis of the lens.
The first image sensor is arranged on an axis connecting the optical axis of the lens and the center of the half mirror so that a sensor surface is perpendicular to the axis,
The second image sensor is on an axis perpendicular to an axis connecting the optical axis of the lens and the center of the half mirror and in a direction in which the half mirror is inclined with respect to the lens. Are arranged so that the sensor surface is vertical,
The distance between the half mirror center and the first image sensor and the distance between the half mirror center and the second image sensor are different from each other. Optical three-dimensional shape measuring device. A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An irradiation surface position calculating means for calculating a position,
The light incident vector detection means includes a half mirror that divides the reflected light into two directions of first reflected light and second reflected light, a first lens that collects the first reflected light, and the second reflected light. A second lens that collects the first reflected light, a first image sensor that receives the first reflected light, and a second image sensor that receives the second reflected light,
The half mirror is arranged to be inclined with respect to the measurement object,
The first lens is disposed on an axis connecting the measurement object and the half mirror so that one end surface side is perpendicular to the axis, and the first image sensor is connected to the other end surface side of the first lens. It is arranged so that the sensor surfaces are parallel,
The second lens is on an axis perpendicular to an axis connecting the measurement object and the center of the half mirror, and the half mirror is inclined with respect to the measurement object with respect to the axis. And the second image sensor is arranged such that the other lens surface of the second lens and the sensor surface are parallel to each other.
The distance between the half mirror center and the first lens and the distance between the half mirror center and the second lens are the same distance,
The distance between the first lens and the first image sensor is different from the distance between the second lens and the second image sensor ,
The irradiation surface position calculation means calculates a vector of the reflected light by a three-dimensional vector analysis from a light receiving position of the two image sensors and a geometric condition of the optical system, and calculates a three-dimensional position of the light irradiation surface. optical and three-dimensional shape measurement device characterized by. A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An irradiation surface position calculating means for calculating a position,
The light incident vector detection means includes a transmission sensor that transmits the reflected light, and an image sensor that receives the transmitted light transmitted through the transmission sensor.
The transmission sensor is arranged so that a sensor surface faces the measurement object,
The image sensor is arranged in parallel with the transmission sensor ,
The irradiation surface position calculation means calculates a vector of the reflected light by a three-dimensional vector analysis from a light receiving position of the two image sensors and a geometric condition of the optical system, and calculates a three-dimensional position of the light irradiation surface. optical and three-dimensional shape measurement device characterized by. 5. The optical three-dimensional shape measuring apparatus according to claim 1, further comprising: a light beam scanning unit configured to scan a light beam from the light source on a surface of the measurement object. A light source for irradiating a measurement object with a light beam, light incident vector detection means for detecting an incident vector of reflected light reflected by the light beam irradiation surface irradiated with the light beam on the measurement object, and a three-dimensional image of the light irradiation surface An optical three-dimensional shape measuring method using an optical three-dimensional shape measuring device comprising an irradiation surface position calculating means for calculating a position,
The light incident vector detection means includes an optical system including a lens that collects the reflected light and at least two image sensors.
The two image sensors are arranged such that the sensor surfaces are perpendicular to the optical axis of the lens or an axis in a direction divided from the optical axis, and at different distances from the light irradiation surface,
The irradiation surface position calculating means derives an incident vector to the two image sensors from a light receiving position of the two image sensors and a geometric condition of the optical system by three-dimensional vector analysis, An optical three-dimensional shape measuring method, wherein a three-dimensional position of the light irradiation surface is calculated by deriving a reflection position vector of the light beam. The optical three-dimensional shape measurement method according to claim 6, wherein the three-dimensional shape of the measurement object is measured by scanning a light beam from the light source on the surface of the measurement object.

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