JP2008128729A - Shape measuring device - Google Patents

Abstract

Kind Code: A1 An object of the present invention is to provide a shape measuring apparatus advantageous for measuring a wide area (for example, the whole or almost the whole) of an object to be measured.
A shape measuring apparatus includes a transmitting member holding section 3 that holds a transmitting member 2 having a mounting surface 20 on which an object to be measured 8 is placed and is capable of transmitting laser light, and an object to be measured placed on the transmitting member. 8 stores a light projecting unit 4 that projects laser light, an image capturing unit 5 that captures reflected light of the irradiated portion of the laser light projected from the light projecting unit 4, and imaging data captured by the image capturing unit 5. The projection unit 4 is rotated along the imaginary line of the imaging data storage unit 6 and the mounting surface 20 of the transmission member, and the projection unit 4 is relatively moved with respect to the measurement object 8 along with the rotation. A first drive unit 7 to be operated.
[Selection] Figure 1

Description

  The present invention relates to a shape measuring apparatus that measures the shape of an object to be measured.

  Conventionally, a measuring table for fixing an object to be measured with clay, an emission optical system for guiding laser light projected from a laser light source to the object to be measured, and imaging for imaging spot light of the laser light irradiated on the object to be measured The position of the spot light of the laser light on the surface of the object to be measured is calculated based on the image of the spot light of the laser light captured by the imaging unit, the scanning part that scans the spot light on the surface of the object to be measured, and the imaging part A shape measuring apparatus including a control system is known (Patent Document 1). According to this, the shape of the object to be measured is measured by the principle of triangulation.

  Further, a holding unit that holds and holds the end in the longitudinal direction of the object to be measured, a light projecting unit that irradiates the object to be measured held by the holding unit with laser slit light, and a shape of the object to be measured A cross section provided with an imaging unit for wide-area measurement having an imaging range capable of driving, a drive unit that relatively rotates the object to be measured, and a calculation unit that calculates cross-sectional shape data from imaging data captured by the imaging unit A shape measuring apparatus is known (Patent Document 2). In this case, the shape of the object to be measured is measured by the principle of triangulation.

By the way, in the field of archeology, the measurement of the shape of relics such as excavated stone tools is performed by manual sketches. In this case, in order to make the sketch as accurate as possible, a great deal of man-hours and time are spent. Furthermore, because of manual work, there are variations among people, and there is a limit to improving the reliability of sketches. For example, using a ruler and a caliper, the surface, back, right side, left side, top, and bottom of the relics such as stone tools are sketched and made into an actual measurement. It takes a lot of man-hours and time, and there is a limit to improving the reliability of sketches.
JP 2004-354136 A JP 2001-304827 A

  Even if the techniques according to Patent Documents 1 and 2 described above are applied to the shape measurement of an object to be measured such as a stone tool, there is a limit in measuring a large area (for example, the whole or almost the whole) of the object to be measured such as a stone tool. .

  The present invention has been made in view of the above-described actual situation, and an object thereof is to provide a shape measuring apparatus that is advantageous for measuring a large area (for example, the whole or almost the whole) of an object to be measured.

  (1) A shape measuring apparatus according to aspect 1 includes a mounting surface on which an object to be measured is mounted and a transmitting member holding unit that holds a transmitting member that has a back surface facing the mounting surface and is capable of transmitting laser light; A light projecting unit that projects laser light onto the object to be measured placed on the transmission member, an image capturing unit that captures reflected light from the irradiated portion of the laser light projected from the light projecting unit to the object to be measured, and imaging An imaging data storage unit that stores imaging data captured by the imaging unit, a calculation unit that obtains the shape of the object to be measured based on the imaging data of the imaging data storage unit, and a projection surface and a back surface of the transmission member The projection unit and the imaging unit are rotated along a virtual line on the mounting surface of the transmission member so that the imaging unit and the imaging unit are opposed to each other. It has the 1st drive part which moves an imaging part relatively, It is characterized by the above-mentioned.

  According to aspect 1, the object to be measured is placed on the mounting surface of the transmission member held by the transmission member holding unit. In this state, the light projecting unit projects laser light onto the object to be measured placed on the transmitting member. An imaging part images the irradiation part of the laser beam projected from the light projection part. The imaging data captured by the imaging unit is stored in the imaging data storage unit. A 1st drive part rotates a light projection part and an imaging part along the surroundings of the virtual line of the mounting surface of a permeation | transmission member. As the light projecting unit and the imaging unit rotate, the light projecting unit and the image capturing unit relatively move around the object to be measured. For this reason, if the light projecting unit and the imaging unit are relatively moved over the entire area or almost the entire area of the object to be measured, the shape of the object to be measured can be measured over a large area (for example, the entire area or almost the entire area).

  The transmission member holding unit is a unit that holds a transmission member having a mounting surface on which the object to be measured is placed. The transmitting member may be inorganic glass or organic glass, and in short, it is sufficient that the laser beam can be transmitted. The transmission member is preferably a plate shape, but is not limited thereto. Examples of the object to be measured include natural objects such as shells and stones, parts mounted on vehicles and industrial equipment, and relics such as stone tools. It does not specifically limit as a material of a to-be-measured object, A metal, ceramics, resin, wood, a natural mineral is illustrated. The light projecting unit projects laser light onto the object to be measured placed on the transmission member. As the laser light projected by the light projecting unit to the measured part, a laser slit light having a slit shape is preferable to the pinpoint light in consideration of shortening of the measurement time. The laser light may be P-polarized light or S-polarized light. P-polarized light means light in which the electric field vector of the light wave is parallel to the incident surface (surface perpendicular to the mounting surface) of the transmissive member. S-polarized light means light in which the electric field vector of the light wave is perpendicular to the incident surface (surface perpendicular to the mounting surface) of the transmissive member. Since the reflectance of P-polarized light is smaller than that of S-polarized light, P-polarized light is preferable in order to reduce noise caused by reflection. The imaging unit images the irradiated portion of the laser light projected from the light projecting unit. As an imaging part, it is preferable to provide two imaging elements arrange | positioned so that a light projection part may be pinched | interposed. The imaging data storage unit stores imaging data captured by the imaging unit. The calculation unit obtains the shape of the device under test based on the imaging data stored in the imaging data storage unit. The first driving unit rotates the light projecting unit and the imaging unit around the imaginary line of the mounting surface of the transmission member, and relatively moves the light projecting unit and the imaging unit around the object to be measured along with the rotation. It says what you want. In this case, as the first driving unit, it is preferable to rotate the light projecting unit by 300 degrees or more, particularly 360 degrees along the imaginary line of the mounting surface of the transmission member. The first drive unit can be formed using a motor device, a cylinder device, or the like.

  (2) According to the shape measuring apparatus according to aspect 2, in aspect 1, the second drive unit that moves the measurement object placed on the transmission member relative to the light projecting unit is provided. And In this case, the second drive unit moves the measurement object placed on the transmission member relative to the light projecting unit. For this reason, it is advantageous for measuring the entire area or almost the entire area of the object to be measured. The second driving unit may be any unit that moves the object to be measured mounted on the transmission member relative to the light projecting unit, and examples thereof include a motor device and a cylinder device.

  (3) According to the shape measuring apparatus according to the aspect 3, in the aspect 1 or 2, when the X direction and the Y direction are horizontal two-dimensional directions and the Z direction is the height direction, the second drive unit is measured An XYZ driving unit that moves the object in the X direction, the Y direction, and the Z direction while the object is placed on the transmission member; and at least along a plane defined by the X direction and the Y direction while the object to be measured is placed on the transmission member And a rotation drive unit that rotates 180 degrees. In this case, the XYZ driving unit moves the object to be measured in the X direction, the Y direction, and the Z direction while being placed on the transmission member. The rotation driving unit rotates at least 180 degrees while placing the object to be measured on the transmission member. This is advantageous for measuring a large area (for example, the entire area or almost the entire area) of the object to be measured. As the XYZ drive unit, a Z-direction drive unit that moves the object to be measured in the Z direction while being placed on the transmission member, a Y-direction drive unit that is to move the measurement object in the Y direction while being placed on the transmission member, and a measurement object A configuration having an X-direction drive unit that moves an object in the X-direction while being placed on the transmission member is exemplified. The rotation drive unit may be anything as long as the object to be measured is rotated at least 180 degrees while being placed on the transmission member.

  (4) According to the shape measuring apparatus according to aspect 4, in aspects 1 to 3, the laser light projected by the light projecting unit to the measured part is P-polarized light or S-polarized light.

  When the incident angle of the laser beam increases with respect to the transmission member, the reflectance of P-polarized light is smaller than that of S-polarized light. For this reason, P-polarized light is advantageous in reducing reflected light noise. In addition, since S-polarized light has a high reflectance, an advantage is obtained in that a reflected image of an object to be measured having a low reflectance can be taken.

  (5) According to the shape measuring apparatus according to aspect 5, in aspects 1 to 4, the projection is performed so that the laser light projected from the light projecting unit is positioned obliquely on the mounting surface of the transmission member. The light portion rotates with respect to the transmission member. The reflectance of P-polarized light is smaller than that of S-polarized light. Since the laser light projected from the light projecting unit is incident on the mounting surface of the transmission member from an oblique direction, if the laser light is P-polarized light, it is advantageous for reducing reflected light noise.

  According to the present invention, the light projecting unit and the image capturing unit are rotated along the imaginary line along the mounting surface of the transmission member, and the light projecting unit and the image capturing unit are rotated with respect to the object to be measured along with the rotation. Move relative. For this reason, it becomes advantageous to image and measure a large area (for example, the whole or almost the whole) of the shape of the object to be measured.

  According to the present invention, the transmitting member can transmit laser light. For this reason, the light projecting unit and the image capturing unit are arranged so that the light projecting unit and the image capturing unit face the back surface opposite to the mounting surface on which the object to be measured is placed, among the transmitting members. The back surface of the object to be measured can also be imaged by transmitting the laser light projected from the section through the transmission member. In this sense as well, it is advantageous for measuring a large area (for example, the whole or almost the whole) of the object to be measured.

(Embodiment 1)
Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 shows the concept of the shape measuring apparatus. As shown in FIG. 1, the shape measuring device functioning as a shape imaging device includes a base 1 having legs 1c, a transmission plate 2 functioning as a transmission member on which an object to be measured 8 (an object to be imaged, a workpiece) is placed, A transmission plate holding unit 3 that holds the transmission plate 2, a light projecting unit 4 that projects laser light onto the measurement object 8 placed on the transmission plate 2, and a light projection from the light projection unit 4 to the measurement object 8. The imaging unit 5 that captures the reflected light from the irradiated portion of the laser beam, the image memory 6 that functions as an imaging data storage unit that stores the imaging data captured by the imaging unit 5, and the mounting surface 20 of the transmission plate 2 A first drive unit 7 is provided for rotating the light projecting unit 4 along the vertical direction around a virtual line M virtually defined above.

  As shown in FIG. 2, the light projecting unit 4 includes a light projecting element 40 composed of a semiconductor laser (wavelength: 660 nanometers) and a light transmitting device disposed on the tip side of the light projecting element 40 (measurement object 8 side). A cylindrical lens 41 that functions as an optical lens, and a half-wave plate (optical wavelength plate) provided on the front side of the cylindrical lens 41 (on the side of the object to be measured 8) are provided. The half-wave plate 42 is an electronic birefringent plate having a function of rotating the polarization plane of light. The cylindrical lens 41 is a lens having a transmissive surface 41a and a refracting surface 41c, and can enlarge one direction in the vertical and horizontal directions of the spot of the laser beam. From the point-shaped laser beam to the slit-shaped laser beam, that is, the laser slit beam 47. Can be formed. The refracting surface 41c forms a part of a cylindrical shape. The laser slit light 47 has slit edges 47a and 47c that expand into a slit fan shape as the light travels.

  The light projecting element 40 formed of a semiconductor laser emits an ellipse. When the laser slit light 47 is generated, the longitudinal axis direction of the light emission ellipse is usually widened by the cylindrical lens 41 provided in the light projecting unit 4 in order to narrow the slit width in a wider range. In this state, the laser slit light 47 is S-polarized light (meaning light in which the electric field vector of the light wave is perpendicular to the incident surface of the transmission plate 2). However, since the laser slit light 47 is transmitted through the half-wave plate 42, the laser slit light 47 is P-polarized light (meaning light whose electric field vector of the light wave is parallel to the incident surface of the transmission plate 2).

  The output (intensity) of the light projecting element 40 of the light projecting unit 4 is controlled by the laser output control unit 330. In particular, the laser output control unit 330 controls the light projection intensity of the laser slit light 47 projected from the light projecting element 40. The laser slit light 47 described above is P-polarized light.

  The transmission plate 2 is a transparent plate (thickness: 5 to 8 millimeters, material: float glass), and has a disk shape with an outer periphery 25. The transmission plate 2 can transmit the laser slit light 47 of the light projecting element 40. The transmission plate 2 includes a mounting surface 20 that is an upper surface and a back surface 22 (see FIG. 3) that faces the mounting surface 20. The mounting surface 20 and the back surface 22 are along a horizontal plane and have a flat shape. An object to be measured 8 is detachably mounted on the mounting surface 20 of the transmission plate 2. The transmission plate 2 preferably has a larger projected area than the object 8 to be measured. Since the mounting surface 20 has a two-dimensional horizontal plane, it is not necessary to hold the object 8 to be measured by clay or the like, and if the object 8 is placed at an appropriate position on the mounting surface 20 of the transmission plate 2. good. In some cases, when the posture of the measurement object 8 is not stable, the measurement object 8 may be held on the mounting surface 20 of the transmission plate 2 with clay or the like as necessary.

  In FIG. 1, the imaging unit 5 captures the reflected light of the irradiated portion of the laser slit light 47 projected from the light projecting element 40 of the light projecting unit 4. The imaging unit 5 has two imaging elements formed by CCD elements arranged at positions sandwiching the light projecting element 40 so as to reduce the measurement blind spot in the measurement object 8 even if the measurement object 8 is uneven. Elements, that is, a first image sensor 51 and a second image sensor 52 are provided. The imaging directions of the first imaging element 51 and the second imaging element 52 are directed toward the object 8 to be measured on the transmission plate 2. The image pickup signals of the first image pickup device 51 and the second image pickup device 52 are stored in predetermined areas of the image memory 6. The light projecting unit 4 and the imaging unit 5 described above are integrally incorporated in the case 90 of the sensor 9 and can be moved by the same amount in the same direction. The case 90 of the sensor 9 is shared by the light projecting unit 4 and the imaging unit 5 and functions as a common case.

  FIG. 1 shows an X direction, a Y direction, and a Z direction in the coordinate system of the shape measuring apparatus. The Z direction is a gravity direction. The X direction and the Y direction indicate a horizontal two-dimensional direction. The first drive unit 7 moves the sensor 9 relative to the sensor 9 (the light projecting unit 4 and the light projecting unit 4) along the virtual line M virtually defined on the placement surface 20 of the transmission plate 2. The imaging device is rotated with respect to the transmission plate 2 and the base 1.

  As shown in FIG. 1, the first drive unit 7 has a rotation mechanism unit 70 held on the base 1 so as to rotate the sensor 9 and a horizontal axis provided on the rotation mechanism unit 70. The rotary shaft 71 has a horizontal axis, a rotation plate 72 in which a mounting region 72 a as a central region is fixed to the rotation shaft 71, and a sensor mounting portion 73 provided on the rotation plate 72. The sensor 9 is attached to the sensor attachment portion 73. Accordingly, the sensor 9 including the light projecting unit 4 and the imaging unit 5 is attached to the outer peripheral side of the rotating plate 72. A balancer 74 is provided on the rotating plate 72 on the side opposite to the sensor mounting portion 73. The balancer 74 reduces the unbalance of the weight by the sensor attachment part 73, and makes the rotation of the turntable 72 smooth. As a result, noise such as vibration noise is reduced.

  The rotation mechanism unit 70 is controlled by a sensor rotation control unit 320. Here, when the rotation mechanism unit 70 is driven, the rotation shaft 71 rotates around the axis PB, the sensor 9 rotates about the axis PB, and is held by the sensor 9. The light projecting unit 4 and the imaging unit 5 are rotated around the axis PB. As a result, the light projecting unit 4 and the imaging unit 5 rotate (relatively move) along the virtual line M (horizontal axis type) of the placement surface 20 of the transmission plate 2. Thus, the horizontal axis PB serves as a rotation center of the light projecting unit 4 and the imaging unit 5 held by the sensor 9. The height position of the shaft core PB is preferably set slightly above the placement surface 20 of the transmission plate 2. The axis PB is parallel to the imaginary line M.

  Further, as shown in FIG. 1, a second drive unit 100 is provided. The second driving unit 100 moves the object 8 placed on the transmission plate 2 relative to the light projecting unit 4 and irradiates the entire area of the object 8 with the laser slit light 47. The second drive unit 100 transmits an X-YZ drive unit 120 that moves the measurement object 8 in the X direction, the Y direction, and the Z direction while the measurement object 8 is placed on the transmission plate 2 and transmits the measurement object 8 while the measurement object 8 is placed on the transmission plate 2. A rotation drive unit 150 that rotates at least 180 degrees around a normal MC that stands upright with respect to the mounting surface 20 of the plate 2 is provided.

  As shown in FIG. 1, the rotation drive unit 150 keeps the object 8 to be measured on the transmission plate 2, and the normal MC of the central area of the transmission plate 2 (perpendicular to the mounting surface 20 of the transmission plate 2). ) Around 360 degrees (at least 180 degrees). The rotation driving unit 150 includes a transmission plate holding unit 3 that rotatably holds the transmission plate 2, a case 152 that holds the transmission plate holding unit 3, and a rotation mechanism (not shown) built in the case 152. )). When the rotation mechanism is driven, the transmission plate 2 is rotated around the normal line MC. The rotation drive unit 150 is controlled by the measured object rotation control unit 300. Further explanation will be given below.

  As shown in FIG. 1, the XYZ driving unit 120 includes a Z-direction driving unit 123 having a Z-direction guide unit 122 that moves the Z slider 121 in the Z direction (gravity direction) while the DUT 8 is placed on the transmission plate 2. A Y-direction drive unit 125 having a Y-direction guide unit 124 that moves the Z-direction drive unit 123 in the Y direction (width direction of the measurement target 5) while the DUT 8 is placed on the transmission plate 2, and a DUT An X-direction drive unit 128 having an X-direction guide unit 127 that moves the Y-direction drive unit 125 in the X direction (the length direction of the measured object 8) while the object 8 is placed on the transmission plate 2 is provided. The XYZ drive unit 120 is controlled by the XYZ control unit 310. When the XYZ driving unit 120 is driven, the object to be measured 8 on the transmission plate 2 can be appropriately moved in the X direction, the Y direction, and the Z direction.

  Signals output from the XYZ control unit 310, the sensor rotation control unit 300, the image memory 6, the laser output control unit 330, and the measured object rotation control unit 300 are input to the calculation unit 360 (control unit). . Based on the signals output from the sensor rotation control unit 300 and the measured object rotation control unit 300, the calculation unit 360 can detect the position of the measured object 8. As a result, the calculation unit 360 grasps the imaging signal imaged by the imaging unit 5 and the position of the DUT 8. The calculation unit 360 calculates the shape data of the device under test 8 based on the relationship between the image signal captured by the image capturing unit 5 and the position of the device under test 8. The calculation unit 360 outputs control signals for controlling the XYZ control unit 310, the sensor rotation control unit 300, the laser output control unit 330, and the measured object rotation control unit 300, respectively.

  Based on the imaging data obtained by the first image sensor 51 or the second image sensor 52, the shape of the DUT 8 is measured by the arithmetic unit 360 according to the principle of triangulation. Here, the triangulation method uses the triangular shape of the object to be measured 8, the light projecting unit 4, and the first image sensor 51, and irradiates the light to be measured 8 from the light projecting unit 4. This is a surveying method in which the position of the irradiated portion is imaged and measured by the first image sensor 51 from another direction. In the present embodiment, since the unevenness on the surface of the object to be measured 8 is complicated, if only the first image sensor 51 is used, there is a possibility that a blind spot for image capturing in the object 8 to be measured may occur. In addition, a second image sensor 52 is provided.

  The basic principle of the triangulation method will be described by taking the first image sensor 51 as an example. In FIG. 4, a base line that linearly connects the observation surface of the first imaging unit element 51 and the light projecting unit 4 is defined as K. The length L of the base line K is known. An angle formed by the base line K and the laser beam of the light projecting unit 4 is defined as θa. Let ω be the angle at which the laser beam reflected by the DUT 8 is incident on the first image sensor 51 that is the observation optical system (the angle at which the laser beam incident on the first image sensor 51 and the base line K intersect). Here, if the coordinate change Δx on the observation surface of the first image sensor 51 can be measured, the irradiation position of the laser beam on the measurement object 8 irradiated by the first image sensor 51 can be determined. Here, if the angle θa formed by the length L of the base line K and the laser beam (an emission angle from the light projecting unit 4 to the object 8 to be measured) is fixed, the angle changes according to the shape of the surface of the object 8 to be measured. The shape of the surface of the DUT 8 can be determined from the coordinate change Δx on the observation surface.

  In use, the object to be measured 8 is placed on the placement surface 20 of the transmission plate 2 as shown in FIG. In this state, as shown in FIG. 3, the sensor 9 is rotated to a position U <b> 1 just above the object 8 to be measured on the mounting surface 20, and the laser beam is projected from the light projecting unit 4 to the surface 8 a of the object 8 to be measured. The slit light 47 is projected, and the reflected light is imaged by the first image sensor 51 and the second image sensor 52. Further, the sensor 9 is rotated to a position U2 to the right of the object 8 to be measured on the mounting surface 20, and the laser slit light 47 is projected from the light projecting unit 4 to the right side surface 8b of the object 8 to be measured. The reflected light is imaged by the first image sensor 51 and the second image sensor 52. Further, as shown in FIG. 3, the sensor 9 is rotated to a position U <b> 3 just below the object 8 to be measured on the mounting surface 20, and the back surface 8 c of the object 8 is measured with the first imaging element 51 and the second imaging. An image is picked up by the element 52. Thus, when imaging the back surface 8c of the object 8 to be measured, the laser slit light 47 projected on the object 8 is transmitted from the back surface 22 of the transmission plate 2 through the transmission plate 2 in the thickness direction. To do. Further, the sensor 9 is rotated to a position U4 on the left side of the object 8 to be measured on the placement surface 20, and the first image sensor 51 and the second image sensor 52 image the left side surface 8d of the object 8 to be measured. To do.

  According to the present embodiment, as described above, when the object 8 of the transmission plate 2 is imaged by the imaging unit 5, when the object 8 is imaged without transmitting the laser slit light 47 through the transmission plate 2 ( In the case of imaging the surface 8a, the right side surface 8b, and the left side surface 8d of the object 8 to be measured placed on the transmission plate 2) and in the case of imaging the object 8 to be measured by transmitting the laser slit light 47 through the transmission plate 2. (When imaging the back surface 8c of the DUT 8 placed on the transmission plate 2). The transmission form of the laser slit light 47 is not uniform between the case where the laser slit light 47 does not pass through the transmission plate 2 and the case where the laser slit light 47 passes through the transmission plate 2 in the thickness direction thereof. For this reason, it is preferable to correct the shape data from the actual measurement values captured by the imaging unit 5.

  FIG. 5 shows a map stored in the image memory 6. FIG. 5A shows a shape based on measured values (α11, α12, α13, α14... Α98, α99) of imaging data captured by the first imaging element 51 when the laser slit light 47 does not pass through the transmission plate 2. The map which extracts data (A11, A12, A13, A14 ...) is shown. Further, FIG. 5A shows the shape data (B11, B12, B13, B14... B98, B99) from the actual measurement values (β11, β12, β13, β14...) Of the imaging data captured by the second image sensor 52. Indicates the map to be extracted.

  FIG. 5B shows measured values (α11, α12, α13, α14... Α98, α99) of imaged data captured by the first image sensor 51 when the laser slit light 47 is transmitted through the transmission plate 2. , A map for extracting correction values (shape data A11, A12, A13, A14... By adding Δα11, Δα12, Δα13). FIG. 5B shows shape data obtained by adding correction values (Δβ11, Δβ12, Δβ13...) To the actual measurement values (β11, β12, β13, β14...) Of the imaging data captured by the second image sensor 52. The map which extracts (B11, B12, B13, B14 ...) is shown. The relationship between the actual measurement value and the shape data is obtained by projecting a laser slit light onto a sample having a known shape and size and taking an image. Further, the relationship between the actually measured value, the correction value, and the shape data is obtained by projecting a laser slit light onto a sample having a known shape and size and imaging the sample.

  Since the above-described map is provided, when the object to be measured 8 is imaged without transmitting the laser slit light 47 through the transmission plate 2, and the object 8 is measured by transmitting the laser slit light 47 through the transmission plate 2. Shape data can be obtained in good response to the case of imaging.

  According to the present embodiment, as the laser slit light 47 projected on the object 8 to be measured, S-polarized light (meaning light whose electric field vector of the light wave is perpendicular to the incident surface of the transmission plate 2) is used. Alternatively, P-polarized light (which means light whose electric field vector of the light wave is parallel to the incident surface of the transmission plate 2) may be used. However, when using P-polarized light, the following excellent effects can be obtained.

  FIG. 6 shows the relationship between the incident angle θ1 and the reflectance (R) and the transmittance (T) at the placement surface 20 of the transmission plate 2 when laser light is incident on the placement surface 20 of the transmission plate 2. A graph is shown (n1 = 1.0, n2 = 1.5). n1 means the refractive index of air and the refractive index of the glass constituting the mounting surface 20. As shown in FIG. 7, the incident angle θ <b> 1 is defined as the angle between the normal line of the mounting surface 20 of the transmission plate 2 and the laser beam. In FIG. 6, the horizontal axis represents the incident angle θ1, and the vertical axis represents the reflectance (R) and the transmittance (T). As shown in FIG. 6, regarding the reflectance, when the incident angle θ1 is small, there is no large difference between the reflectance of P-polarized light and the reflectance of S-polarized light, but when the incident angle θ1 increases, the reflectance is higher than the reflectance of S-polarized light. The reflectance of P-polarized light is low. Further, as shown in FIG. 6, the transmittance does not differ greatly between the transmittance of P-polarized light and the transmittance of S-polarized light when the incident angle θ1 is small, but from the transmittance of S-polarized light when the incident angle θ1 increases. Also, the transmittance of P-polarized light is increased. Considering the characteristics shown in FIG. 6, the incident angle θ1 is preferably 81 degrees or less, particularly 65 degrees or less.

  In consideration of the result shown in FIG. 6, when S-polarized light is used as the laser slit light 47, when the incident angle θ <b> 1 of the laser slit light 47 incident on the mounting surface 20 of the transmission plate 2 increases, The reflectance on the mounting surface 20 of the transmissive plate 2 is increased, and noise due to the reflectance may be increased. Here, when imaging the front surface, the right side surface, the back surface, and the left side surface of the measurement object 8 on the mounting surface 20 of the transmission plate 2, the mounting surface 20 of the transmission plate 2 from the light projecting element 40 of the light projecting unit 4. The incident angle θ1 of the laser slit light 47 incident on the light tends to increase. In this case, when the incident angle θ1 increases, noise due to the increase in the incident angle θ1 may easily occur.

  In this regard, according to the present embodiment, in consideration of the characteristics shown in FIG. 6 described above, the P-polarized light is projected onto the object 8 as the laser slit light 47. As a result, even when the incident angle θ1 of the laser slit light 47 incident on the mounting surface 20 of the transmission plate 2 increases, that is, with respect to the object 8 to be measured on the mounting surface 20 of the transmission plate 2. Thus, even when the laser slit light 47 is incident from the side of the object 8 to be measured, an increase in reflectance is suppressed. Therefore, noise due to an increase in reflectance is reduced, and the measurement accuracy for measuring the shape of the DUT 8 can be improved. According to the present embodiment, when the laser slit light 47 projected on the object 8 to be measured is P-polarized light, the half-wave plate 42 is added to the light projecting unit 4 as shown in FIG. Yes.

  Alternatively, when the laser slit light 47 is changed to P-polarized light, the laser slit light 47 is generated by spreading the laser slit light 47 with the cylindrical lens 41 with the polarization direction of the laser slit light 47 as the slit longitudinal direction. Accordingly, the laser slit light 47 may be changed from S-polarized light to P-polarized light.

  As described above, according to the present embodiment, the DUT 8 is placed on the mounting surface 20 of the transmission plate 2 and is held on the transmission plate 2 by frictional force. Further, the light projecting unit 4 and the imaging unit 5 are rotated around a virtual imaginary line M defined along the mounting surface 20 on the mounting surface 20 of the transmission plate 2. Therefore, the surface 8a of the measurement object 8 placed on the placement surface 20 of the transmission plate 2 (the surface of the measurement object 8 facing away from the placement surface 20 of the transmission plate 2), the measurement object 8 In addition to the right side surface 8b and the left side surface 8d, the back surface 8c of the object to be measured 8 (the surface of the object to be measured 8 directly facing the mounting surface 20 of the transmission plate 2) can be imaged. The reason is that, firstly, the laser slit light 47 can be transmitted through the transparent transmission plate 2, and secondly, the sensor 9 including the light projecting unit 4 and the imaging unit 5 moves relative to the transmission plate 2. This is because it is possible. As a result, the shape of the entire area of the object to be measured 8 or almost the entire area can be measured.

  Furthermore, according to this embodiment, the mounting surface 20 of the transmission plate 2 is a flat shape spreading two-dimensionally. For this reason, the posture of the measurement object 8 can be stably held on the placement surface 20 of the transmission plate 2 without holding the measurement target 8 on the placement surface 20 of the transmission plate 2 with clay. However, in some cases, when the shape of the object 8 to be measured is considerably irregular and it is difficult to maintain the posture of the object 8 to be measured, a small amount of clay may be used. Although there is a possibility that the image of the clay is taken, if there is an understanding of the presence or absence of the clay, there is no problem. Furthermore, according to this embodiment, when the size of the measurement object 8 is larger than the measurement range of the sensor 9, the measurement object 8 on the transmission plate 2 can be appropriately moved by the XYZ driving unit 120 to be measured. The shape of the entire area of the object 8 or almost the entire area can be measured.

(Embodiment 2)
Next, Embodiment 2 of the present invention will be described with reference to FIGS. 8 to 10 show the concept of the usage state of the shape measuring apparatus according to the present embodiment. Since this embodiment has basically the same configuration as that of the first embodiment, description of the configuration is omitted. Parts having the same function are denoted by the same reference numerals. However, the turntable 72 has an arm shape. The sensor attachment portion 73 for attaching the sensor 9 has an L shape. The sensor mounting portion 73 is shown in FIG. 8A, but is omitted in other drawings.

  Hereinafter, description is added about the usage method of the shape measuring apparatus of this embodiment.

(1) Measurement of the surface 8a (upper surface) of the object 8 to be measured As shown in FIG. 8A, the object 8 to be measured is placed near the center of the mounting surface 20 of the transmission plate 2. The sensor 9 (the light projecting unit 4 and the imaging unit 5) is disposed directly above the object 8 to be measured on the mounting surface 20 of the transmission plate 2 so as to be parallel to the mounting surface 20 of the transmission plate 2. Yes. In this example, when the sensor 9 is directly above the transmission plate 2, the rotation phase of the sensor 9 is 0 degree. In this state, as shown in FIG. 8A, the light projecting unit 4 and the imaging unit 5 held by the sensor 9 are arranged directly above the object to be measured 8. In this case, as shown in FIG. 8A, the sensor 9 → the object to be measured 8 → the transmission plate 2 are arranged in this order from the top to the bottom.

  Laser slit light 47 is projected from the light projecting element 40 of the light projecting unit 4 toward the object 8 to be measured on the transmission plate 2. The reflected light reflected from the surface 8 a of the object to be measured 8 is imaged by the first image sensor 51 and the second image sensor 52 of the sensor 9. The calculation unit 360 obtains shape data from the obtained imaging data. By driving the X-direction drive unit 128, the shape of the object 8 to be measured is moved while moving the object 8 to be measured on the transmission plate 2 along the X direction (longitudinal direction of the object 8). Is measured and used as the shape data of the surface 8a of the object 8 to be measured.

(2) Measurement of the right side surface 8b of the object 8 to be measured Next, as shown in FIG. 8B, the sensor 9 is rotated 90 degrees in the arrow S direction (rotation direction), and the side of the object 8 to be measured is And the rotation phase of the sensor 9 is 90 degrees. In this state, the light projecting unit 4 and the imaging unit 5 held by the sensor 9 are disposed on the right side 8b side (right side) of the object 8 to be measured. Laser slit light 47 is projected from the light projecting element 40 of the light projecting unit 4 toward the object 8 to be measured on the transmission plate 2. The reflected light reflected from the right side surface 8 b of the DUT 8 is imaged by the first image sensor 51 and the second image sensor 52 of the sensor 9. The calculation unit 360 obtains shape data from the obtained imaging data. In addition, by driving the X-direction drive unit 128, the cross-sectional shape of the measurement object 8 is measured while moving the measurement object 8 in the X direction (longitudinal direction of the measurement object 8) at a predetermined pitch, and the measurement object is measured. The shape data of the right side surface 8b of the object 8 is used.

(3) Measurement of Back Surface 8c of Measured Object 8 Next, as shown in FIG. 9A, the sensor 9 is further rotated 90 degrees in the arrow S direction (rotation direction) to measure the measured object 8 and the transmission plate. The rotation phase of the sensor 9 is 180 degrees. In this state, the light projecting unit 4 and the imaging unit 5 held by the sensor 9 are disposed directly below the object 8 to be measured via the transmission plate 2. In this case, as shown in FIG. 9A, the measurement object 8 → the transmission plate 2 → the sensor 9 are arranged in this order from the top to the bottom.

  As shown in FIG. 9A, the laser slit light 47 is projected from the light projecting element 40 of the light projecting unit 4 toward the object 8 to be measured on the transmission plate 2, that is, upward. In this case, the laser slit light 47 passes through the transmission plate 2 and reaches the measured object 8 to the back surface 8c. The reflected light reflected by the back surface 8 c of the object to be measured 8 is imaged by the imaging unit 5 of the sensor 9. The calculation unit 360 obtains shape data from the obtained imaging data. In addition, by driving the X-direction drive unit 128, the cross-sectional shape of the measurement object 8 is measured while moving the measurement object 8 in the X direction (longitudinal direction of the measurement object 8) at a predetermined pitch, and the measurement object is measured. The shape data of the back surface 8c of the object 8 is used.

(4) Measurement of the left side surface 8d of the measurement object 8 Next, as shown in FIG. 9B, the sensor 9 is further rotated 90 degrees in the arrow S direction (rotation direction) to the left side of the measurement object 8. It arrange | positions at the surface 8d side (left side), and makes the rotation phase of the sensor 9 be 270 degree | times. In this state, the light projecting unit 4 and the image sensors 51 and 52 held by the sensor 9 are arranged on the left side of the object 8 to be measured.

  Laser slit light 47 is projected from the light projecting element 40 of the light projecting unit 4 toward the object 8 to be measured on the transmission plate 2. The reflected light reflected by the left side surface of the measurement object 8 is imaged by the imaging unit 5 of the sensor 9. The calculation unit 360 obtains shape data from the obtained imaging data. In addition, by driving the X-direction drive unit 128, the cross-sectional shape of the DUT 8 is measured while moving the DUT 8 in the X direction (longitudinal direction of the DUT 8) at a predetermined pitch. The shape data of the left side surface 8d of the measurement object 8 is used.

(5) Measurement of the upper surface 8e of the measurement object 8 (one end side in the longitudinal direction of the measurement object 8) Next, as shown in FIG. The sensor 9 is rotated 90 degrees in the direction (rotation direction) and arranged to the right of the object 8 to be measured, and the rotation phase of the sensor 9 is set to 90 degrees. Further, the transmission plate 2 and the device under test 8 are rotated 90 degrees in the direction of the arrow E1 so that the upper surface 8e of the device under test 8 (one end side in the longitudinal direction of the device under test 8) faces the sensor 9. Then, the laser slit light 47 is projected from the light projecting element 40 of the light projecting unit 4 toward the object 8 to be measured on the transmission plate 2. The reflected light reflected from the upper surface 8 e of the object to be measured 8 is imaged by the imaging elements 51 and 52 of the sensor 9. The calculation unit 360 obtains shape data from the obtained imaging data. In addition, by driving the X-direction drive unit 128, the cross-sectional shape of the DUT 8 is measured while moving the DUT 8 in the X direction (longitudinal direction of the DUT 8) at a predetermined pitch. The shape data of the upper surface 8e of the measurement object 8 can be used.

(6) Measurement of the lower surface 8f of the device under test 8 (the other end in the longitudinal direction of the device under test 8) Next, as shown in FIG. 10 (B), the sensor 9 is further moved in the arrow S direction (rotation direction). The sensor 9 is rotated 180 degrees and arranged on the right side of the object 8 to be measured, and the rotation phase of the sensor 9 is set to 270 degrees. As a result, the other end side in the longitudinal direction of the DUT 8, that is, the lower surface 8 f of the DUT 8 is made to face the sensor 9. Then, the laser slit light 47 is projected from the light projecting element 40 of the light projecting unit 4 toward the lower surface 8 f of the object 8 to be measured on the transmission plate 2. The reflected light reflected from the back surface of the device under test 8 is imaged by the first image sensor 51 and the second image sensor 52 of the sensor 9. The calculation unit 360 measures shape data from the obtained imaging data. In addition, by driving the X-direction drive unit 128, the cross-sectional shape of the DUT 8 is measured while moving the DUT 8 in the X direction (longitudinal direction of the DUT 8) at a predetermined pitch. The shape data of the lower surface 8f of the measurement object 8 can be used.

  As described above, also in this embodiment, the measurement object 8 is placed on the placement surface 20 of the transmission plate 2 and is held on the transmission plate 2 by friction. For this reason, it is possible to measure the shape of the entire area of the object to be measured 8 placed on the placement surface 20 of the transmission plate 2 or almost the whole area. Since the mounting surface 20 of the transmission plate 2 spreads two-dimensionally, the posture of the measurement target 8 can be changed to that of the transmission plate 2 without holding the measurement target 8 on the mounting surface 20 of the transmission plate 2 with clay. It can be stably held on the mounting surface 20. However, in some cases, when the shape of the object 8 to be measured is considerably irregular and it is difficult to maintain the posture of the object 8 to be measured, a small amount of clay may be used. Although there is a possibility that the image of the clay is taken, if there is an understanding of the presence or absence of the clay, there is no problem.

  Furthermore, according to this embodiment, when the size of the measurement object 8 is larger than the measurement range of the sensor 9, the measurement object 8 on the transmission plate 2 can be appropriately moved by the XYZ driving unit 120 to be measured. The shape of the entire area of the object 8 or almost the entire area can be measured.

(Embodiment 3)
The third embodiment basically has the same configuration and the same function and effect as the first and second embodiments. Therefore, FIGS. 1 and 3 to 10 can be applied mutatis mutandis. However, S-polarized light is projected onto the object 8 as the laser slit light 47.

(Other)
In the first and second embodiments described above, the light projecting unit 4 includes the half-wave plate 42 and forms P-polarized light. However, two quarter-wave plates may be arranged in series. . In the first and second embodiments described above, the measurement object 8 on the transmission plate 2 is moved relative to the base 1 in measuring the shapes of the upper surface 8e and the lower surface 8f of the measurement object 8. The shape of the upper surface 8e and the lower surface 8f of the measured object 8 is not limited to this, and the measured object 8 on the transmission plate 2 is fixed and the sensor 9 is rotated around the measured object 8. May be measured. The imaging order of the front surface 8a, the right side surface 8b, the back surface 8c, the left side surface 8d, etc. of the device under test 8 is not particularly limited. The object to be measured 8 is not limited to stone tools, but may be relics other than stone tools, natural objects such as shells and stones, parts mounted on vehicles and industrial equipment (including bolts, nuts, washers, etc.), stone tools Examples of such relics. It does not specifically limit as a material of the to-be-measured object 8, A metal, ceramics, resin, wood, a natural mineral is illustrated.

The following technical idea can also be grasped from the above description.
[Additional Item 1] A transmissive member holding portion for holding a transmissive member that has a placement surface on which an object to be imaged is placed and a back surface that faces away from the placement surface, and is capable of transmitting laser light, and the transmissive member. A light projecting unit that projects laser light onto the object to be imaged, an image capturing unit that captures reflected light of a portion irradiated with the laser light projected from the light projecting unit onto the imaged object, and the imaging An imaging data storage unit that stores imaging data captured by the imaging unit, and the above description of the transmission member such that the light projecting unit and the imaging unit face the placement surface and the back surface of the transmission member. A first driving unit configured to rotate the light projecting unit along a virtual line on the placement surface and move the light projecting unit and the image capturing unit relative to the object to be imaged with the rotation; A shape imaging apparatus. The light projecting unit and the imaging unit are rotated along an imaginary line along the mounting surface of the transmission member, and the light projecting unit and the imaging unit are moved relative to the object to be measured along with the rotation. This is advantageous for imaging a large area (for example, the whole or almost the whole) of the shape of the object to be measured.
[Additional Item 2] The shape imaging apparatus according to Additional Item 1, further comprising a second drive unit that moves the object to be imaged mounted on the transmission member relative to the light projecting unit. .

  Examples of the present invention include a shape measuring device that images the shape of an object to be measured (an object to be imaged) such as a relic such as a stone tool or a shell (excavated article), a vehicle part, or an industrial part.

1 is a configuration diagram schematically showing a concept of a shape measuring apparatus according to Embodiment 1. FIG. FIG. 3 is a configuration diagram schematically illustrating a light projecting unit according to the first embodiment. FIG. 4 is a configuration diagram schematically showing a usage pattern according to the first embodiment. It is a figure which shows the principle of a triangulation method. FIG. 4 is a diagram illustrating a map in which measured values and correction values are stored in an area of an image memory according to the first embodiment. It is a graph showing the relationship between the incident angle θ1 and the reflectance (R) and the transmittance (T) on the mounting surface of the transmission plate when laser light is incident on the mounting surface of the transmission plate. It is a block diagram which shows the definition of incident angle (theta) 1. FIG. FIG. 9A is a configuration diagram schematically illustrating a state in which the surface of the object to be measured is measured by the shape measuring device according to the second embodiment, and FIG. It is a block diagram which shows the state currently measured typically. FIG. 5A is a configuration diagram schematically showing a state in which the back surface of the object to be measured is measured by the shape measuring device according to the second embodiment, and (B) is a diagram illustrating the left side surface of the object to be measured by the shape measuring device. It is a block diagram which shows the state currently measured typically. FIG. 9A is a configuration diagram schematically illustrating a state in which the upper surface of the object to be measured is measured by the shape measuring device according to the second embodiment, and FIG. 9B is a diagram illustrating the lower surface of the object to be measured by the shape measuring device. It is a block diagram which shows typically the state which is carrying out. FIG. 6 is a diagram according to the second embodiment, in which the surface, the right side, the left side, the back, the top, and the bottom of a stone tool are imaged as the measurement object.

Explanation of symbols

  1 is a base, 2 is a transmission plate (transmission member), 20 is a placement surface, 22 is a back surface, 3 is a transmission plate holding portion (transmission member holding portion), 4 is a light projecting portion, and 40 is a light projecting element. , 41 is a cylindrical lens, 42 is a half-wave plate, 5 is an imaging unit, 6 is an image memory (imaging data storage unit), 7 is a first drive unit, 8 is an object to be measured, 9 is a sensor, and 100 is a first sensor. Reference numeral 2 denotes a drive unit, 120 denotes an XYZ drive unit, and 150 denotes a rotation drive unit.

Claims (5)

A transmissive member holding portion for holding a transmissive member having a placement surface on which the object to be measured is placed and a back surface facing away from the placement surface, and capable of transmitting laser light;
A light projecting unit that projects laser light onto the object to be measured placed on the transmission member;
An imaging unit that images reflected light of the irradiated portion of the laser light projected from the light projecting unit to the object to be measured;
An imaging data storage unit for storing imaging data captured by the imaging unit;
A calculation unit for obtaining the shape of the object to be measured based on the imaging data in the imaging data storage unit;
The light projecting unit is arranged along an imaginary line on the mounting surface of the transmitting member so that the light projecting unit and the imaging unit face the mounting surface and the back surface of the transmitting member. A shape measuring apparatus comprising: a first drive unit that is rotated and moves the light projecting unit and the imaging unit relative to the object to be measured along with the rotation.   The shape measuring apparatus according to claim 1, further comprising a second driving unit that moves the measurement object placed on the transmission member relative to the light projecting unit.   In Claim 1 or 2, when the X direction and the Y direction are horizontal two-dimensional directions and the Z direction is the height direction, the second drive unit places the measured object on the mounting surface of the transmission member. XYZ driving unit that moves in the X direction, Y direction, and Z direction while being mounted, and rotates at least 180 degrees along a plane defined by the X direction and the Y direction while the object to be measured is mounted on the transmission member A shape measuring device comprising: a rotation driving unit for causing the shape measuring device.   4. The shape measuring apparatus according to claim 1, wherein the laser beam projected from the light projecting unit to the measured unit is P-polarized light or S-polarized light.   In any one of Claims 1-4, so that the said laser beam projected from the said light projection part may be in the position which injects into the said mounting surface or the said back surface of the said transmissive member from an oblique direction, The shape measuring device, wherein the light projecting portion rotates with respect to the transmitting member.

Images