JP4795191B2 - Position measuring sensor, three-dimensional position measuring apparatus, and three-dimensional position measuring method - Google Patents

Description

  The present invention relates to a position measuring sensor, a three-dimensional position measuring apparatus, and a three-dimensional position measuring method for detecting a bright spot provided on an object and measuring a three-dimensional position of the object.

  Conventionally, as a technique for measuring the three-dimensional position of an object, two cameras are arranged at different angles with respect to the object, and based on the positional relationship between these cameras and the image of the object acquired by these cameras. A stereo camera method for measuring the three-dimensional position of an object is known. In the stereo camera method, the corresponding points of the object in each image acquired by the two cameras are searched, and the distance information to the object is obtained based on the principle of triangulation based on the positional deviation amount of these corresponding points. Can do.

ここで、画像上での対象点Ｐの位置ずれ量ｄは、次式（３）により表現することができる。

つまり、次式（４）を用いて、求めることができる。

FIG. 14 is a schematic diagram for explaining a three-dimensional position measurement method by a conventional stereo camera method. Cameras 51 and 52 shown in FIG. 14 have the same internal parameters, and are arranged so that the horizontal axes Xc of the cameras 51 and 52 coincide. At this time, the coordinates U ₁ and U ₂ of the target point P on the images acquired by the cameras 51 and 52 are expressed by the following expressions (1) and (2) (where f: focal length, b: Distance between cameras 51 and 52).

Here, the positional deviation amount d of the target point P on the image can be expressed by the following equation (3).

That is, it can be obtained using the following equation (4).

  However, the conventional stereo camera method uses a camera with a video frame rate (30 frames / s) and requires complex image processing such as edge extraction processing and left-right image matching processing in searching for corresponding points. It was. This makes it difficult to perform three-dimensional position measurement at high speed.

  Therefore, as a technique for solving the problems in the three-dimensional position measurement by the stereo camera method, a profile sensor (light detection device) that is a sensor having an image processing function has been proposed (for example, see Patent Document 1). FIG. 15 is a schematic configuration diagram of a profile sensor. As shown in FIG. 15, the profile sensor 61 includes a plurality of pixels 62 that are two-dimensionally arranged, and each pixel 62 is divided into two light receiving regions 63 and 64. One light receiving region 63 is electrically connected in the X direction, and the other light receiving region 64 is electrically connected in the Y direction.

When the profile sensor 61 detects light, it outputs projection (profile) data in the X and Y directions. When performing three-dimensional position measurement of an object using such a profile sensor 61, a plurality of bright spots (light) provided on the object are detected, and the output data is processed to obtain a plurality of The position information of the bright spot can be acquired to determine the three-dimensional position of the object. An ordinary m × n pixel two-dimensional sensor outputs m × n data, whereas the profile sensor 61 outputs m + n data. That is, in the profile sensor 61, the output data is greatly compressed, so that subsequent processing can be simplified. As a result, the speed of the three-dimensional position measurement can be increased, and the profile sensor 61 that is reduced in size and price can be provided.
International Publication No. 03/049190 Pamphlet

  However, in the conventional technique described in Patent Document 1, when a plurality of bright spots provided on an object overlap in the connection direction (X direction, Y direction) of the light receiving region, projection data in the X direction and the Y direction are obtained. It was difficult to separate the position information of each bright spot from For this reason, it is difficult to accurately acquire the position information of each bright spot, and the position measurement accuracy may be lowered.

  The present invention has been made in order to solve such problems. A position measurement sensor, a three-dimensional position measurement apparatus, and a three-dimensional position measurement apparatus that are designed to speed up position measurement and improve position measurement accuracy. An object is to provide a position measurement method.

  A position measurement sensor according to the present invention is a position measurement sensor that detects light from a plurality of bright spots provided on an object, and includes a first profile sensor having a photosensitive region in which pixels are two-dimensionally arranged, and a first profile sensor. The pixel includes two profile sensors, and each pixel has a plurality of light-sensitive portions that output a current corresponding to the intensity of incident light, arranged adjacent to each other in the same plane, and arranged in a first direction in a two-dimensional array. Across the plurality of pixels, one of the plurality of photosensitive portions constituting each pixel is electrically connected, and over the plurality of pixels arranged in the second direction in the two-dimensional array, The other photosensitive portions of the plurality of photosensitive portions constituting each pixel are electrically connected to each other, the electrical connection direction of the photosensitive portions in the first profile sensor, and the second profile section. It is characterized in that the electrical connection direction between the photosensitive portions do not match the service.

  According to such a position measurement sensor, the first profile sensor and the second profile sensor are electrically connected across a plurality of pixels in which one photosensitive portion is arranged in the first direction in the two-dimensional array. And the other photosensitive parts are electrically connected across a plurality of pixels arranged in the second direction in the two-dimensional array, so that the projection data in the first direction and the projection in the second direction Data can be obtained independently. Therefore, the subsequent image processing can be simplified, and the speed of the three-dimensional position measurement of the target can be increased. In the position measurement sensor, the electrical connection direction between the photosensitive portions in the first profile sensor and the electrical connection direction between the photosensitive portions in the second profile sensor do not coincide with each other. Even if multiple bright spots overlap in the electrical connection direction of the light sensitive parts of the sensor, multiple bright spots do not overlap in the electrical connection direction of the light sensitive parts of the other profile sensor. In addition, accurate position information of each bright spot can be acquired. Therefore, it is possible to improve the position measurement accuracy.

  The three-dimensional position measurement apparatus according to the present invention includes a position measurement sensor that detects light from a plurality of bright spots provided on an object, and a drive signal generation unit that outputs a drive signal for driving the position measurement sensor. And a three-dimensional position calculating means for calculating a three-dimensional position of the object based on a detection signal from the position measuring sensor, and the position measuring sensor has a photosensitive region in which pixels are two-dimensionally arranged. The pixel includes a first profile sensor and a second profile sensor, and each pixel has a plurality of photosensitive portions that output a current corresponding to the intensity of incident light and are arranged adjacent to each other in the same plane. Across the plurality of pixels arranged in the first direction in FIG. 1, one of the plurality of photosensitive portions constituting each pixel is electrically connected, and arranged in the second direction in the two-dimensional array. The The other photosensitive portions of the plurality of photosensitive portions constituting each pixel are electrically connected across the plurality of pixels, the electrical connection direction of the photosensitive portions in the first profile sensor, and the first In the second profile sensor, the electrical connection directions of the photosensitive portions do not coincide with each other.

  According to such a three-dimensional position measuring apparatus, the first profile sensor and the second profile sensor are electrically connected over a plurality of pixels in which one photosensitive portion is arranged in the first direction in the two-dimensional arrangement. And the other photosensitive parts are electrically connected across a plurality of pixels arranged in the second direction in the two-dimensional array, so that the projection data in the first direction and the second direction Can be obtained independently from each other. Therefore, the subsequent image processing can be simplified, and the speed of the three-dimensional position measurement of the target can be increased. In the position measurement sensor, the electrical connection direction between the photosensitive portions in the first profile sensor and the electrical connection direction between the photosensitive portions in the second profile sensor do not coincide with each other. Even if multiple bright spots overlap in the electrical connection direction of the light sensitive parts of the sensor, multiple bright spots do not overlap in the electrical connection direction of the light sensitive parts of the other profile sensor. In addition, accurate position information of each bright spot can be acquired. Therefore, it is possible to improve the position measurement accuracy.

  The three-dimensional position measurement method according to the present invention is a three-dimensional position measurement method that measures the three-dimensional position of an object using a position measurement sensor that detects light from a plurality of bright spots provided on the object. The position measurement sensor includes a first profile sensor and a second profile sensor each having a photosensitive region in which pixels are two-dimensionally arranged, and each pixel outputs a current corresponding to the intensity of incident light. A plurality of light-sensitive portions are arranged adjacent to each other in the same plane, and one of the light-sensitive portions constituting each pixel extends over a plurality of pixels arranged in the first direction in the two-dimensional array. The sensitive parts are electrically connected to each other, and the other photosensitive parts of the plurality of photosensitive parts constituting each pixel are electrically connected to each other over a plurality of pixels arranged in the second direction in the two-dimensional array. Connected and second The second profile sensor is used as the first profile sensor so that the electrical connection direction of the photosensitive portions in the profile sensor of FIG. 2 does not match the electrical connection direction of the photosensitive portions in the second profile sensor. It is characterized by being tilted with respect to it.

  According to such a three-dimensional position measuring method, one photosensitive portion is electrically connected across a plurality of pixels arranged in the first direction in the two-dimensional array, and the other photosensitive portion is two-dimensional. Since profile sensors electrically connected across a plurality of pixels arranged in the second direction in the array are used, projection data in the first direction and projection data in the second direction are obtained independently. It becomes possible. Therefore, the subsequent image processing can be simplified, and the speed of the three-dimensional position measurement of the target can be increased. Further, in the three-dimensional position measurement method, the second electrical connection direction between the photosensitive portions in the first profile sensor is not matched with the electrical connection direction between the photosensitive portions in the second profile sensor. The profile sensor is inclined with respect to the first profile sensor. Thereby, even if a plurality of bright spots overlap in the electrical connection direction between the light-sensitive portions of one profile sensor, a plurality of light connections in the electrical connection direction between the light-sensitive portions of the other profile sensor. Since the bright spots do not overlap, accurate position information of each bright spot can be acquired. Therefore, it is possible to improve the position measurement accuracy.

  According to the position measurement sensor, the three-dimensional position measurement device, and the three-dimensional position measurement method of the present invention, it is possible to increase the speed of position measurement and improve the position measurement accuracy.

  Hereinafter, a preferred first embodiment of a position measurement sensor, a three-dimensional position measurement device, and a three-dimensional position measurement method according to the present invention will be described with reference to the drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted. FIG. 1 is a schematic configuration diagram of a three-dimensional position measuring apparatus including a position measuring sensor according to a first embodiment of the present invention, and FIG. 2 is a plan view of a package containing a profile sensor according to the first embodiment of the present invention. 3 is a schematic configuration diagram showing the profile sensor according to the first embodiment of the present invention, and FIG. 4 is a plan view specifically showing the photosensitive region according to the first embodiment of the present invention.

  A three-dimensional position measurement apparatus 1 shown in FIG. 1 measures the three-dimensional position and orientation of an object 2, and first detects light from a plurality of bright spots 3 to 5 provided on the object 2. The sensor unit (position measurement sensor) 8 including the profile sensor 6 and the second profile sensor 7, and the sensor unit 8 are controlled, and an object is detected based on the detection signal (projection data) from the sensor unit 8. 2 and a calculation unit 9 for calculating the three-dimensional position.

  The plurality of bright spots 3 to 5 provided on the object 2 are set to different brightness and size so as to have different projection data (bright spot profiles). The bright spots 3 to 5 are configured by, for example, a light emitting device such as an LED or a reflective device such as a reflector.

  The sensor unit 8 includes a first profile sensor 6 and a second profile sensor 7 arranged at different positions. The first profile sensor 6 and the second profile sensor 7 have the same configuration. The first profile sensor 6 and the second profile sensor 7 are installed at different angles (details will be described later). Hereinafter, when referring to both the first profile sensor 6 and the second profile sensor 7, they are referred to as profile sensors 6 and 7.

  As shown in FIG. 2, the profile sensors 6 and 7 are accommodated in, for example, an LCC package 14 of 7.6 mm × 7.6 mm. A photosensitive region 10 that functions as a photodiode is formed at the center of the profile sensors 6 and 7. Further, as shown in FIG. 3, the profile sensors 6 and 7 include a first signal processing circuit 20 and a second signal processing circuit 30 in addition to the photosensitive region 10.

The photosensitive region 10 includes a plurality of pixels 11 _mn that are two-dimensionally arranged in M rows and N columns. Each pixel 11 _mn has a photosensitive portion 12 _mn (one photosensitive portion) and a photosensitive portion 13 _mn (the other photosensitive portion) that output a current according to the intensity of the incident light adjacent to each other in the same plane. Prepared.

Adjacent photosensitive portions 12 _mn are a plurality of pixels 11 _{11 to} 11 _1N , 11 _{21 to} 11 _2N ,..., 11 arranged in the X direction (first direction, vertical direction in FIG. 3) in a two-dimensional array. _{M1 to} 11 are electrically connected to each other over the _MN . Adjacent photosensitive portions 13 _mn are a plurality of pixels 11 _{11 to} 11 _1N , 11 _{21 to} 11 _2N ,... Arranged in the Y direction (second direction, horizontal direction in FIG. 3) in a two-dimensional array. , 11 _{M1 to} 11 _MN are electrically connected to each other. Thus, by electrically connecting the photosensitive portions 12 _mn in the X direction and electrically connecting the photosensitive portions 13 _mn in the Y direction, the X direction projection data and the Y direction projection data are obtained. Each can be obtained independently.

As shown in FIG. 4, the photosensitive region 10 includes a semiconductor substrate 40 made of a P-type (first conductivity type) semiconductor, and an N-type (second conductivity type) semiconductor formed on the surface layer of the semiconductor substrate 40. Regions 41 and 42. The semiconductor region 41 corresponds to the above-described photosensitive portion 12 _mn , and the semiconductor regions 41 adjacent in the X direction are electrically connected to each other by the first wiring 44. The semiconductor region 42 corresponds to the above-described photosensitive portion 13 _mn , and the semiconductor regions 42 adjacent in the Y direction are electrically connected to each other by the second wiring 47.

As shown in FIG. 3, the first signal processing circuit 20 is electrically connected to the photosensitive portion 12 _mn (semiconductor region 41) connected in the X direction, and light incident on the photosensitive region 10 in the X direction. A signal indicating the luminance profile (X-direction projection data) is output to the calculation unit 9. The first signal processing circuit 20, photosensitive portions 12 _mn and electrically connected to the switching element, a shift register for reading the current from the photosensitive portions 12 _mn, converts the current read by the shift register into a voltage Integration circuit for output.

As shown in FIG. 3, the second signal processing circuit 30 is electrically connected to the photosensitive portion 13 _mn (semiconductor region 42) connected in the X direction, and light incident on the photosensitive region 10 in the Y direction. A signal indicating the luminance profile (Y direction projection data) is output to the calculation unit 9. The first signal processing circuit 30 converts photosensitive portions 13 _mn and electrically connected to the switching element, a shift register for reading the current from the photosensitive portions 13 _mn, the current read by the shift register into a voltage Integration circuit for output.

  The calculation unit 9 is output from the drive signal generation circuit (drive signal generation means) 15 that drives the first profile sensor 6 and the second profile sensor 7, the first profile sensor 6, and the second profile sensor 7. In-plane position calculation circuit 16 for calculating in-plane positions of corresponding points corresponding to a plurality of bright spots 3 to 5 based on X-direction projection data and Y-direction projection data, and corresponding points obtained by in-plane position calculation circuit 16 Is provided with a three-dimensional position calculation circuit 17 for calculating the parallax of the bright spots 3 to 5 based on the in-plane position and calculating the distance from the sensor unit 8 to the object 2. The calculation unit 9 is electrically connected to the first profile sensor 6 and the second profile sensor 7. The in-plane position calculation circuit 16 and the three-dimensional position calculation circuit 17 function as the three-dimensional position calculation means of the present invention, and calculate the three-dimensional position of the object 2 based on the detection signal from the sensor unit 8. To do.

Next, searching for in-plane positions of corresponding points corresponding to a plurality of bright spots 3 to 5 will be described with reference to FIGS. 5 to 9, the rectangular frame corresponds to the photosensitive region 10, and the data X _{1 to} X ₅ extending in the X direction are X direction projection data output from the first signal processing circuit 20. The data Y _{1 to} Y ₆ extending in the Y direction are Y direction projection data output from the second signal processing circuit 30. Each of the data X _{1 to} X ₅ and Y _{1 to} Y ₆ indicates the peak of the voltage value and has a substantially triangular shape, the size of the area of the triangle indicates the luminance value of the bright spot, and the half of the triangle The value width indicates the shape of the bright spot.

First, the search for the in-plane position of the corresponding point when a plurality of bright spots do not overlap in the X and Y directions will be described. FIG. 5 shows an example of a detection signal by the profile sensor according to the first embodiment of the present invention, and is a diagram when a plurality of bright spots do not overlap in the X direction and the Y direction. When the plurality of bright spots 3 to 5 do not overlap in the X direction and the Y direction, as shown in FIG. 5, the same number of peaks as the number of bright spots 3 to 5 are detected in the X direction and the Y direction, X direction projection data X _{1 to} X ₃ and Y direction projection data Y _{1 to} Y ₃ are acquired.

FIG. 6 is a diagram illustrating in-plane positions of corresponding point candidates estimated based on the detection signals illustrated in FIG. 5. FIG. 7 is a diagram showing the in-plane positions of corresponding points obtained based on the detection signals shown in FIG. As shown in FIG. 6, on the lines L _{1 to} L ₃ extending in the X direction from the position where the X direction projection data X _{1 to} X ₃ are detected, Y is determined from the position where the Y direction projection data Y ₁ to Y ₃ is detected. Presence of corresponding points corresponding to the bright spots 3 to 5 can be estimated on the lines L _{4 to} L ₆ extending in the direction. That is, the intersection point Q of the lines L _{1 to} L ₆ can be estimated as a corresponding point candidate position. For each intersection Q, the areas and half widths of the X direction projection data X _{1 to} X ₃ are compared with the areas and half widths of the Y direction projection data Y _{1 to} Y ₃ , and those that differ greatly in value are sequentially excluded. Then, as shown in FIG. 7, the corresponding point P can be obtained.

Next, the search for the in-plane position of the corresponding point when some of the plurality of bright spots overlap in the X direction will be described. FIG. 8 shows an example of a detection signal by the profile sensor according to the first embodiment of the present invention, and is a diagram when a part of a plurality of bright spots overlap in the X direction. When a plurality of bright spots 3 to 5 are overlapped in the X direction, as shown in FIG. 8, a peak having a quantity smaller than the quantity of bright spots 3 to 5 is detected, and the X direction projection data X ₄ and X ₅ are detected. , Y-direction projection data _Y 4 to Y ₆ is obtained.

FIG. 9 is a diagram showing in-plane positions of corresponding point candidates estimated based on the detection signals shown in FIG. As shown in FIG. 9, Y is determined from the positions where the Y direction projection data Y ₄ to Y ₆ are detected on the lines L ₇ and L ₈ extending in the X direction from the position where the X direction projection data X ₄ and X ₅ are detected. Presence of corresponding points corresponding to the bright spots can be estimated on the lines L _{9 to} L ₁₁ extending in the direction. That is, the intersection point Q of the lines L7 to L11 is estimated as a corresponding point candidate position. Then, for each intersection point Q, the area and half value width of the X direction projection data X ₄ and X ₅ are compared with the area and half value width of the Y direction projection data Y _{4 to} Y ₆ , and the corresponding point is obtained. When bright spots overlap in the direction, the quantity of the X direction projection data X ₄ and X ₅ decreases, and the position accuracy of the corresponding points may decrease.

Therefore, the first profile sensor 6 and the second profile sensor 7 are arranged so that their axes (X direction and Y direction) do not coincide. FIG. 10 is a schematic diagram showing the arrangement of the first profile sensor and the second profile sensor according to the first embodiment of the present invention. Specifically, as shown in FIG. 10, the second profile sensor 7 is inclined by an angle θ with respect to the first profile sensor 6. Here, “the axes do not coincide with each other” means that the X direction and Y direction in the first profile sensor 6 are not parallel to the X direction and Y direction in the second profile sensor 7. . That is, the first profile sensor 6 and the second profile sensor 7 have different electrical connection directions of the photosensitive portion 12 _mn and the photosensitive portion 13 _mn . Thereby, even if some of the plurality of bright spots overlap in the X direction or Y direction of the first profile sensor 6, some of the bright spots in the X direction and Y direction of the second profile sensor 7. Similarly, even when a part of the plurality of bright spots overlaps in the X direction or Y direction of the second profile sensor 7, the X direction and Y direction of the first profile sensor 6 do not overlap. It is possible to prevent some of the bright spots from overlapping.

Note that the inclination angle θ of the second profile sensor 7 with respect to the first profile sensor 6 is based on the size (diameter) and arrangement (the distance from the profile sensor to the bright spot, etc.) of the bright spots 3 to 5 to be measured. Is set. For example, the size of the bright spots 3 to 5 corresponds to 5 pixels in the profile sensors 6 and 7, and the distance from the profile sensors 6 and 7 to the bright spots 3 to 5 corresponds to 50 pixels in the profile sensors 6 and 7. When two of the plurality of bright spots 3 to 5 overlap in the X direction or the Y direction in the first profile sensor 6, the second profile sensor does not overlap in the X direction and the Y direction. Can be obtained by the inclination angle θ = tan ⁻¹ (5/50) (5). In this case, the inclination angle θ is about 6 degrees.

Further, when the second profile sensor 7 is tilted with respect to the first profile sensor 6 by the tilt angle θ, the second profile sensor 7 is a position tilted with respect to the first profile sensor 6 by the tilt angle θ. As measured. When the coordinate system (x ₂ , y ₂ ) in the second profile sensor 7 corresponds to the coordinate system (x ₁ , y ₁ ) in the first profile sensor 6, x ₁ = x ₂ cos θ + y ₂ sin θ (6) ), Y ₁ = −x ₂ sin θ + y ₂ cos θ (7).

  Next, a three-dimensional position measurement method executed using such a three-dimensional position measurement apparatus 1 will be described. First, the profile sensors 6 and 7 are arranged at predetermined positions with respect to the object 2 having a plurality of bright spots 3 to 5. The second profile sensor 7 is arranged to be inclined with respect to the first profile sensor 6 so as to form an inclination angle θ. That is, by preventing the axes of the first profile sensor 6 and the second profile sensor 7 from overlapping each other, the electrical connection direction of the photosensitive portion can be changed between the first profile sensor 6 and the second profile sensor. Is not matched. Then, the calculation unit 9 is electrically connected to the profile sensors 6 and 7, respectively, so that detection signals from the profile sensors 6 and 7 can be input.

  Next, the drive signal generation circuit 15 of the arithmetic unit 9 transmits the drive signal to drive the profile sensors 6 and 7. The profile sensors 6 and 7 detect light from a plurality of bright spots 3 to 5 provided on the object 2, and send detection signals (projection data, particularly in the X direction) to the in-plane position calculation circuit 16 of the calculation unit 9. When it is not necessary to distinguish between the projection data and the Y-direction projection data, it is described as projection data). The transmitted projection data is calculated by the in-plane position calculation circuit 16 and the three-dimensional position calculation circuit 17.

  Next, calculation processing executed by the in-plane position calculation circuit 16 and the three-dimensional position calculation circuit 17 will be described with reference to the flowchart of FIG. FIG. 11 is a flowchart showing an operation procedure of calculation processing executed by the in-plane position calculation circuit 16 and the three-dimensional position calculation circuit 17 according to the first embodiment of the present invention. The in-plane position calculation circuit 16 first inputs projection data from the profile sensors 6 and 7 (S1).

Next, the in-plane position calculation circuit 16 obtains in-plane positions of corresponding points corresponding to the plurality of bright spots 3 to 5 based on the projection data input from the profile sensors 6 and 7 (S2). Specifically, the in-plane position of the corresponding point is obtained by comparing the peak area and peak half width of the X direction projection data with the peak area and peak half width of the Y direction projection data. Here, when a plurality of bright spots overlap in the X direction and the Y direction in the first profile sensor 6, the in-plane position of the corresponding point based on the projection data detected by the second profile sensor 7. In the case where a plurality of bright spots overlap in the X direction and the Y direction in the second profile sensor 7, the corresponding point is calculated based on the projection data detected by the first profile sensor 6. Find the in-plane position. Hereinafter, the corresponding point obtained based on the projection data acquired by the first profile sensor 6 is referred to as “corresponding point by the first profile sensor”, and similarly, the projection data acquired by the second profile sensor 7 The corresponding point obtained based on this is referred to as “corresponding point by the second profile sensor”. Further, the in-plane position calculation circuit 16 performs the rotation correction by using the above formulas x ₁ = x ₂ cos θ + y ₂ sin θ (6), y ₁ = −x ₂ sin θ + y ₂ cos θ (7) to obtain the second profile. The corresponding point by the sensor is converted from the coordinate system (x ₂ , y ₂ ) in the _second profile sensor to the coordinate system (x ₁ , y ₁ ) in the first profile sensor.

  Next, based on the in-plane position of each corresponding point obtained by the in-plane position calculating circuit 16, the three-dimensional position calculating circuit 17 corresponds to the corresponding point by the first profile sensor 6 and the corresponding point by the second profile sensor. To find the parallax. The three-dimensional position calculation circuit 17 calculates the distance to a plurality of bright spots based on the parallax of the corresponding points to obtain the three-dimensional position of the target object 2 (S3). Then, the three-dimensional position calculation circuit 17 outputs the three-dimensional position of the target object 2 as a result (S4).

Next, a case where some of the plurality of bright spots overlap in the X direction of the first profile sensor 6 will be described with reference to FIG. FIG. 12 shows an example of a detection signal when some of the plurality of bright spots overlap in the X direction of the first profile sensor, an example of the detection signal from the first profile sensor on the left side, and the right side. It is a figure which shows an example of the detection signal by a 2nd profile sensor. As shown in FIG. 12, the first profile sensor 6 obtains X-direction projection data X ₁₁ and X ₁₂ and Y-direction projection data Y _{11 to} Y ₁₃ , and the second profile sensor 7 obtains X-direction projection data. X _{21 to} X ₂₃ and Y direction projection data Y _{21 to} Y ₂₃ are acquired.

When a plurality of bright spots overlap with each other in the X direction in the first profile sensor 6, the first profile sensor 6 reduces the X-direction projection data X ₁₁ and X ₁₂ as described above. The in-plane position of the corresponding point is obtained using the X-direction projection data X _{21 to} X ₂₃ and the Y-direction projection data acquired by the second profile sensor 7 arranged to be inclined with respect to the profile sensor 6.

The in-plane position calculation circuit 16 compares the peak area and the peak half width, and associates the X direction projection data with the Y direction projection data. In the data shown in FIG. 12, X-direction projection data _{X 21} and Y-direction projection data _{Y 23,} X-direction projection data _{X 22} and Y-direction projection data _{Y 21,} X-direction projection data _{X 23} and Y-direction projection data _{Y 22} corresponds is doing. Next, the in-plane position calculation circuit 16 calculates the in-plane positions of the corresponding points P _{23 to} P ₂₅ in the coordinate system of the second profile sensor 7. Next, the in-plane position calculation circuit 16 performs rotation correction and converts the corresponding points P _{23 to} P ₂₅ into the coordinate system in the first profile sensor 6.

The three-dimensional position calculation circuit 17 refers to the coordinates of the corresponding points P _{23 to} P ₂₅ converted into the coordinate system of the first profile sensor 6, and the corresponding point P ₁₃ and the corresponding point P ₂₃ correspond to each other. It determines that a point _{P 14} and the corresponding point _{P 24} corresponds a corresponding point _{P 15} and the corresponding point _{P 25} corresponds. The three-dimensional position calculation circuit 17 calculates the parallax of the corresponding points P _{13 to} P ₁₅ and P _{23 to} P ₂₅ to obtain the three-dimensional position of the target object 2.

  In the sensor unit 8, the three-dimensional position measurement device 1, and the three-dimensional position measurement method, the second profile sensor 7 is used as the first profile sensor so that the axes (X direction and Y direction) do not coincide with each other. 6 is inclined with respect to 6. Thereby, even if a plurality of bright spots overlap in the X direction or Y direction of one profile sensor, the plurality of bright spots do not overlap in the X direction and Y direction of the other profile sensor. Accurate position information of each bright spot can be acquired by the profile sensor. As a result, it is possible to improve the position measurement accuracy.

Also, one photosensitive portion 12 _mn is electrically connected across a plurality of pixels 11 _mn arranged in the X direction, and the other photosensitive portion 13 _mn is _extended across a plurality of pixels 11 _mn arranged in the Y direction. Since they are electrically connected, X-direction projection data and Y-direction projection data can be obtained independently of each other. Therefore, the subsequent image processing can be simplified, and the three-dimensional position measurement of the object 2 can be speeded up. In addition, the apparatus can be reduced in size.

  Next, a position measurement sensor according to a second embodiment of the present invention will be described with reference to FIG. FIG. 13 is a schematic configuration diagram of a position measuring device including a position measuring sensor according to the second embodiment of the present invention. The position measurement device 21 of the second embodiment is different from the position measurement device 1 of the first embodiment in that a sensor unit (position measurement sensor) 28 is provided instead of the sensor unit 8, and the sensor unit 28 is The first profile sensor 26 and the second profile sensor 27 are arranged with respect to the focal position F of one imaging optical system.

  In addition to the profile sensors 26 and 27, the sensor unit 28 includes a lens 22 into which light from a plurality of bright spots 3 to 5 is incident, and a half mirror that is disposed on the back side of the lens 22 and transmits and reflects light. 23.

  The first profile sensor 26 is disposed at a position where the light reflected by the half mirror 23 can be detected, and the second profile sensor 27 is disposed at a position where the light transmitted through the half mirror 23 can be detected. . The second profile sensor 27 is tilted so that the axes (X direction and Y direction) do not coincide with the first profile sensor 6. For this reason, even if a plurality of bright spots overlap in the X direction or Y direction of one profile sensor, the plurality of bright spots do not overlap in the X direction and Y direction of the other profile sensor. Accurate position information of each bright spot can be acquired by the profile sensor. As a result, it is possible to improve the position measurement accuracy.

  Further, in the sensor unit 28, the first profile sensor 26 and the second profile sensor 27 are arranged with respect to the focal position F of one imaging optical system, so that the size of the apparatus is reduced. .

  As mentioned above, although this invention was concretely demonstrated based on the embodiment, this invention is not limited to the said embodiment. In the above embodiment, the position measurement devices 1 and 21 are configured to include two profile sensors, but may be configured to include three or more profile sensors.

1 is a schematic configuration diagram of a three-dimensional position measurement apparatus including a position measurement sensor according to a first embodiment of the present invention. It is a top view of the package which accommodated the profile sensor which concerns on 1st Embodiment of this invention. 1 is a schematic configuration diagram illustrating a profile sensor according to a first embodiment of the present invention. It is a top view which shows concretely the photosensitive area | region which concerns on 1st Embodiment of this invention. An example of the detection signal by the profile sensor which concerns on 1st Embodiment of this invention is shown, and it is a figure in case the some luminescent point has not overlapped in the X direction and the Y direction. It is a figure which shows the in-plane position of the candidate of the corresponding point estimated based on the detection signal shown in FIG. It is a figure which shows the in-plane position of the corresponding point calculated | required based on the detection signal shown in FIG. An example of the output signal by the profile sensor which concerns on 1st Embodiment of this invention is shown, and it is a figure when some of several bright spots have overlapped in the X direction. It is a figure which shows the in-plane position of the candidate of the corresponding point estimated based on the detection signal shown in FIG. It is the schematic which shows arrangement | positioning of the 1st profile sensor and 2nd profile sensor which concern on 1st Embodiment of this invention. It is a flowchart which shows the operation | movement procedure of the arithmetic processing performed with the in-plane position calculating circuit and 3D position calculating circuit which concern on 1st Embodiment of this invention. An example of a detection signal when a part of a plurality of bright spots overlaps in the X direction of the first profile sensor is shown, an example of a detection signal from the first profile sensor on the left side, and a second profile on the right side It is a figure which shows an example of the detection signal by a sensor. It is a schematic block diagram of the position measuring device provided with the position measuring sensor which concerns on 2nd Embodiment of this invention. It is the schematic for demonstrating the three-dimensional position measuring method by the conventional stereo camera method. It is a schematic block diagram of a profile sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Three-dimensional position measuring device, 2 ... Object, 3-5 ... Bright spot, 6, 26 ... 1st profile sensor, 7, 27 ... 2nd profile sensor, 8, 28 ... Sensor part (position measurement sensor) ) 10 ... photosensitive region, 11 _mn ... pixel, 12 _mn ... one photosensitive part, 13 _mn ... the other photosensitive part, 15 ... driving signal generating circuit (driving signal generating means), 16 ... in-plane position calculation Circuit (3D position calculation means), 17... 3D position calculation circuit (3D position calculation means), 21.

Claims (3)

A position measurement sensor that detects light from a plurality of bright spots provided on an object,
A first profile sensor and a second profile sensor having a photosensitive region in which pixels are two-dimensionally arranged;
In the pixel, a plurality of photosensitive portions that output a current corresponding to the intensity of incident light are disposed adjacent to each other in the same plane,
Over the plurality of pixels arranged in the first direction in the two-dimensional array, one of the plurality of photosensitive parts constituting each pixel is electrically connected,
Over the plurality of pixels arranged in the second direction in the two-dimensional array, the other photosensitive parts among the plurality of photosensitive parts constituting each pixel are electrically connected,
The position measuring sensor, wherein an electrical connection direction between the photosensitive portions in the first profile sensor does not match an electrical connection direction between the photosensitive portions in the second profile sensor. A position measurement sensor for detecting light from a plurality of bright spots provided on an object;
Drive signal generating means for outputting a drive signal for driving the position measurement sensor;
Three-dimensional position calculation means for calculating a three-dimensional position of the object based on a detection signal from the position measurement sensor,
The position measuring sensor is
A first profile sensor and a second profile sensor having a photosensitive region in which pixels are two-dimensionally arranged;
In the pixel, a plurality of photosensitive portions that output a current corresponding to the intensity of incident light are disposed adjacent to each other in the same plane,
Over the plurality of pixels arranged in the first direction in the two-dimensional array, one of the plurality of photosensitive parts constituting each pixel is electrically connected,
Over the plurality of pixels arranged in the second direction in the two-dimensional array, the other photosensitive parts among the plurality of photosensitive parts constituting each pixel are electrically connected,
A three-dimensional position measurement apparatus, wherein an electrical connection direction between the photosensitive portions in the first profile sensor does not match an electrical connection direction between the photosensitive portions in the second profile sensor. . A three-dimensional position measurement method for measuring a three-dimensional position of the object using a position measurement sensor that detects light from a plurality of bright spots provided on the object,
The position measuring sensor is
A first profile sensor and a second profile sensor having a photosensitive region in which pixels are two-dimensionally arranged;
In the pixel, a plurality of photosensitive portions that output a current corresponding to the intensity of incident light are disposed adjacent to each other in the same plane,
Over the plurality of pixels arranged in the first direction in the two-dimensional array, one of the plurality of photosensitive parts constituting each pixel is electrically connected,
Over the plurality of pixels arranged in the second direction in the two-dimensional array, the other photosensitive parts among the plurality of photosensitive parts constituting each pixel are electrically connected,
In order that the electrical connection direction of the photosensitive parts in the first profile sensor does not match the electrical connection direction of the photosensitive parts in the second profile sensor, the second profile sensor is A three-dimensional position measuring method, wherein the three-dimensional position measuring method is arranged to be inclined with respect to the first profile sensor.

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