JP2010282100A - Apparatus, method and tool for detecting position of installed camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus, a method and a tool for detecting a position of an installed camera, wherein a positional relationship among a plurality of cameras is correctly grasped by a simple means so that a position of a work can be detected correctly. <P>SOLUTION: The apparatus for detecting the position of the installed camera includes: a detection tool 20 for detecting the positions of the plurality of installed CCD cameras 10a-10d; a detection mark 24 arranged on the detection tool 20; a table 30 for shifting the position of the detection tool 20 so that the detection mark 24 comes within the visual range of each of the CCD cameras 10a-10d; and a camera position calculation part 46 for calculating the positions of the CCD cameras 10a-10d on the basis of the detection marks 24 imaged by the CCD cameras 10a-10d at a plurality of different positions while shifting the position of the detection tool 20 by the table 30. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention provides, for example, a bonding apparatus in which a technique for detecting a camera position for imaging a workpiece for positioning the workpiece when a flat plate-like workpiece such as a liquid crystal module and a cover panel is bonded, and a control thereof. Regarding the method.

  In general, a liquid crystal panel is configured by laminating a liquid crystal module, a protective sheet for protecting the surface, a touch panel for operation, and the like. These liquid crystal modules, protective sheets, touch panels, etc. (hereinafter referred to as “workpieces”) are built into the housing of the liquid crystal module, and in order to avoid contact with the liquid crystal glass due to deformation of the protective panel or touch panel. There was a space.

  However, if an air layer enters between the workpieces, the visibility of the display surface decreases due to reflection of external light. In order to cope with this, bonding is performed by using a bonding material such as a double-sided tape or an adhesive so that a layer filling the space between the workpieces is formed.

  For this reason, in the manufacture of a liquid crystal panel, it is necessary to prepare such an adhesive for at least one workpiece. In addition, in order to accurately position the workpiece to be bonded, it is necessary to provide a positioning device that images the workpiece with a camera and corrects the mutual displacement.

  As described above, for example, techniques disclosed in Patent Documents 1 and 2 have been proposed as techniques for imaging and positioning a workpiece with a camera.

JP 2000-258746 A JP 2003-66466 A

  By the way, as shown in FIG. 7, in order to accurately detect the positions of the workpieces S1 and S2 before bonding, which are arranged opposite to each other by the holding device K, the corners of the upper and lower workpieces S1 and S2 are displayed. It is necessary to detect and position with a plurality of CCD cameras P. For example, if the corners at both ends of the diagonal lines of the workpieces S1 and S2 are detected, the shift of the center of gravity between the workpieces S1 and S2 can be detected from the midpoint of the diagonal lines. Further, the inclination of the workpieces S1 and S2 can be detected from the inclination of the diagonal line.

  In order to accurately specify the positions of the workpieces S1 and S2 from the detected corner coordinates, it is necessary to grasp the installation positions of the cameras P in advance. There are the following methods for indirectly obtaining the installation position of the camera P.

  That is, it is a method of measuring the positional deviation of the workpieces S1 and S2 after bonding, feeding back the values, and calculating the installation position of the camera P in reverse. However, in this method, it takes time to inspect using a product that has already been bonded for adjustment, and it takes time to correct it.

  The present invention has been proposed in order to solve the above-described problems of the prior art, and the object of the present invention is to accurately grasp the positional relationship of a plurality of cameras by a simple means. It is an object of the present invention to provide a camera installation position detection device and detection method capable of accurately detecting a position, and a camera installation position detection jig.

  In order to achieve the above object, a camera installation position detection device according to claim 1 is provided in a plurality of cameras, a detection jig for detecting the installation position of the camera, and the detection jig. The detected mark, a displacement means for displacing the position of the detection jig within a range in which the detection mark is within the field of view of the camera, and the detection jig is displaced by the displacement means. And position calculation means for calculating the position of the camera based on detection marks picked up by the camera at a plurality of different positions.

  According to a fifth aspect of the present invention, there is provided a method for detecting a camera installation position, wherein a plurality of cameras are used to capture at least twice a detection mark provided on a detection jig while changing the position of the detection mark. The camera position is calculated based on the position.

  The camera installation position detection jig according to claim 6 is a camera installation position detection jig for detecting installation positions of a plurality of cameras, wherein at least two detection marks imaged by the camera are planar. The positional relationship seen from the direction is fixed.

  In the inventions of claims 1, 5 and 6 as described above, the camera installation position can be accurately detected from the position of the detection mark imaged by changing the position of the detection jig. It is not necessary to use and judge the installation position of the camera.

  According to a second aspect of the present invention, in the camera installation position detecting device according to the first aspect, the displacement means has a drive mechanism for rotating the detection jig.

  In the invention of claim 2 as described above, since the operation of changing the position of the detection mark is performed by rotating the detection jig, the position of the camera can be calculated in a short time with a simple operation. it can.

  According to a third aspect of the present invention, in the camera installation position detecting device according to the first aspect, when the at least two detection marks are projected in the optical axis direction of the camera, the positional relationship seen from the plane direction is fixed. It is characterized by being.

  In the invention of claim 3 as described above, since the positional relationship of the detection marks is fixed, accurate detection is possible even if the detection jig is displaced.

  According to a fourth aspect of the present invention, in the camera installation position detecting device according to the third aspect, at least two of the detection marks are arranged at positions overlapping when projected in the optical axis direction of the camera. .

  According to a seventh aspect of the present invention, in the camera installation position detecting jig according to the sixth aspect, at least two of the detection marks are arranged at positions overlapping when projected in the optical axis direction of the camera. And

  In the inventions of claims 4 and 7 as described above, the position on each horizontal plane can be accurately calculated even in the case of cameras arranged vertically such as a camera that images a pair of workpieces to be bonded together. it can.

  As described above, according to the present invention, a camera installation position detection device and a detection method capable of accurately detecting the position of a workpiece by accurately grasping the positional relationship between a plurality of cameras with simple means, and A camera installation position detecting jig can be provided.

It is a perspective view showing the whole composition of one embodiment of the present invention. It is a side view of FIG. It is a functional block diagram which shows the control apparatus in embodiment of FIG. It is a flowchart which shows the process sequence in embodiment of FIG. It is explanatory drawing which shows the positional relationship of the detection mark imaged with the CCD camera in embodiment of FIG. It is explanatory drawing which shows the positional relationship of the detection mark imaged with the CCD camera in embodiment of FIG. It is a perspective view which shows the conventional workpiece positioning device.

Next, embodiments of the present invention (hereinafter referred to as embodiments) will be specifically described with reference to the drawings.
[A. Constitution]
First, the configuration of the camera installation position detection apparatus (hereinafter referred to as this apparatus) of the present embodiment will be described. As shown in FIGS. 1 to 3, this apparatus has four CCD cameras 10a, 10b, 10c, and 10d for imaging a workpiece, a detection jig 20, a table 30, a control device 40, and the like. Yes.

  The CCD cameras 10a to 10d are cameras that capture an image of a detection target by detecting reflected light of a built-in light source (coaxial epi-illumination). As shown in FIG. 2, the CCD cameras 10a and 10b arranged on the upper side are cameras for imaging the upper workpiece S2 with the lens surface facing downward. The CCD cameras 10c and 10d arranged below are cameras that take a picture of the lower workpiece S1 with the lens surface facing downward.

  These CCD cameras 10 a to 10 d are supported by arms 11 and 12. The CCD cameras 10a to 10d and the arms 11 and 12 are moved by a camera driving mechanism 13 (see FIG. 3). The camera drive mechanism 13 has a drive source (not shown) and the like, and is a mechanism that drives the arms 11 and 12 (for example, an XY axis drive mechanism).

  The arm 11 moves in a horizontal direction perpendicular to the horizontal plane (X direction and Y direction) by the camera driving mechanism 13 so that the CCD cameras 10a and 10c can be inserted and removed from the upper side of the workpiece S2, and the front, rear, left and right It is provided so as to be able to scan in the direction. Similarly, the arm 12 also moves in the orthogonal linear directions (X direction and Y direction) on the horizontal plane by the camera driving mechanism 13 so that the CCD cameras 10b and 10d can be taken in and out above the workpiece S1. In addition, it is provided so as to be able to scan in the front-rear and left-right directions. As a result, the CCD cameras 10a to 10d can move to positions where the desired points of the workpieces S1 and S2 can be imaged.

  The detection jig 20 is a member in which an upper plate 21 and a lower plate 22 arranged in parallel vertically are connected by four support columns 23. The upper plate 21 and the lower plate 22 are provided with detection marks 24 corresponding to the visual fields of the CCD cameras 10a to 10d, respectively.

  The detection mark 24 may be any mark as long as it is captured by the CCD cameras 10a to 10d and can be extracted by image processing. For example, the detection marks 24 in the present embodiment are round holes formed in the upper plate 21 and the lower plate 22, and four are provided at positions corresponding to the vertices of the rectangle. The positional relationship between the detection marks 24 is fixed not only in the horizontal direction but also in the vertical direction (a relationship seen from the plane direction when projected in the optical axis direction of the camera). That is, even if the detection jig 20 moves, the positional relationship between the detection marks 24 does not change both vertically and horizontally.

  The table 30 is a horizontal table for positioning the detection jig 20 (and the workpiece S1). The table 30 is provided with a table drive mechanism 31 (see FIG. 3). The table drive mechanism 31 is a displacement means for displacing the table 30 in the horizontal direction. For example, the table 30 can be displaced in an orthogonal linear direction (X direction and Y direction) and in a rotation direction (θ direction) by an XY-θ axis drive mechanism.

  The CCD cameras 10a to 10d, the camera drive mechanism 13, the table drive mechanism 31 and the like are controlled by the control device 40. The control device 40 is configured by realizing the following functions by, for example, a dedicated electronic circuit or a computer operating with a predetermined program.

  That is, as shown in FIG. 3, the control device 40 includes a camera drive unit 41, an imaging control unit 42, an image processing unit 43, a mark extraction unit 44, a table drive unit 45, a camera position calculation unit 46, a storage unit 47, and the like. Have.

  The camera drive unit 41 is means for controlling the camera drive mechanism 13. The imaging control unit 42 is means for controlling imaging of the CCD cameras 10a to 10d. The image processing unit 43 is a means for processing images picked up by the CCD cameras 10a to 10d. The mark extraction unit 44 is means for extracting a detection mark from the captured image. The table driving unit 45 is means for controlling the table driving mechanism 31.

  The camera position calculation unit 46 is a means for calculating the camera position from the extracted detection marks and the field frames of the CCD cameras 10a to 10d. The storage unit 47 includes various settings such as the driving amount and direction of each unit, an arithmetic expression, the distance between the detection marks 24 in the detection jig 20, the captured image, the extracted detection mark, and the calculated camera. It is means for storing data such as position.

[B. Action]
The operation of the present embodiment having the above-described configuration is as follows. Note that a computer program for operating a method and a control device for detecting a camera position according to the procedure described below is also one aspect of the present invention.

  First, the arms 11 and 12 are moved by the camera drive unit 41 controlling the camera drive mechanism. As a result, the CCD cameras 10a and 10b move above the upper plate 21 of the detection jig 20, and the CCD cameras 10b and 10d move between the upper plate 21 and the lower plate 22 (step 101). At this time, the detection marks 24 of the detection jig 20 are placed in the field frames of the CCD cameras 10a to 10d, respectively. The target detection marks 24 are a pair of detection marks 24 corresponding to both ends of a rectangular diagonal line.

  Then, the imaging control unit 42 causes the CCD cameras 10a to 10d to image the detection mark 24 (step 102). The captured image is subjected to processing suitable for extraction (for example, conversion into a black and white binary image) by the image processing unit 43 (step 103). The mark extraction unit 44 extracts a detection mark from this image (step 104). Since this extraction method is a well-known technique, description thereof is omitted.

  Next, the table drive unit 45 controls the table drive mechanism 31 to rotate the table 30 within a range in which the detection mark 24 is within the field frames of the CCD cameras 10a to 10d (step 105). . In the same manner as described above, the CCD camera 10a to 10d images the detection mark 24 (step 106). Then, the mark extraction unit 44 extracts the detection mark 24 from the captured image (steps 107 and 108).

  Based on the relationship between the position of the detection mark 24 extracted as described above and the field frames of the CCD cameras 10a to 10d, the camera position calculation unit 46 calculates the position of the camera (step 109).

  Examples of the detection mark 24 imaged in this way are shown in FIGS. FIGS. 5 and 6 show a view frame (rectangular frames A and B) of two CCD cameras arranged in the horizontal direction, like the CCD cameras 10a and 10b or the CCD cameras 10c and 10d. The detection mark whose position has been changed is indicated by a black circle (referred to as the first mark extracted for the first time) and a black square (referred to as the second mark extracted for the second time).

  Various calculation methods are conceivable, but an example is based on the following formula. Each symbol in the following expression corresponds to the symbol shown in FIGS. If the straight line connecting the first marks is the first straight line, and the straight line connecting the second marks is the second straight line, the position of the detection mark 24 is fixed, so the length L of the first straight line and the second straight line L Are equal.

Therefore, assuming an isosceles triangle as shown in FIG. 6, the distance X ′ from the midpoint S of the base to the right side of the frame A and the distance Y ′ to the upper side are obtained by the following formulas 1 and 2. X11 is the distance from the first mark to the right side of the frame A, X21 is the distance from the second mark to the right side of the frame A, Y21 is the distance from the first mark to the upper side of the frame A, and Y21 is This is the distance from the second mark to the upper side of the frame A.

Further, as shown in FIG. 6, assuming an auxiliary line indicating the height of the above-mentioned isosceles triangle, the inclination a and the length L ′ of the auxiliary line are obtained by Expressions 3 and 4.

Next, the distance L′ X in the horizontal direction and the distance L′ Y in the vertical direction from the first mark of the frame B to the middle point S of the frame A are expressed by Equations 5 and 6 is determined.

Further, based on the distance X ′, the distance Y ′, the distance L′ X, the distance L′ Y, the distance X12 from the first mark of the frame B to the right side, and the distance Y12 to the upper side, The horizontal distance PX and the vertical distance PY between the frame A and the frame B are obtained.

  From the positional relationship between the frames A and B, the positional relationship between the CCD camera 10a that captures the frame A and the CCD camera 10b that captures the frame B (or the CCD cameras 10c and 10d) is grasped.

  Since the positional relationship between the upper and lower detection marks 24 is fixed, the displacement between the upper and lower CCD cameras 10a and 10c and the displacement between the upper and lower CCD cameras 10b and 10d are horizontal displacements with respect to the detection mark 24. It can be determined by the difference in quantity.

[C. effect]
According to the present embodiment as described above, the installation positions of the CCD cameras 10a to 10d are accurately determined from the positions of the detection marks 24 that are picked up by the CCD cameras 10a to 10d in advance by changing the position of the detection jig 20. Since it can be detected, it is not necessary to reversely calculate the camera position using the product after bonding.

  Moreover, since the positional relationship between the detection marks 24 is fixed in the detection jig 20 described above, accurate detection is possible even if the detection jig 20 is displaced. Furthermore, since the displacement of the detection jig 20 may be rotated, it can be processed in a short time with a simple operation.

[D. Other Embodiments]
The present invention is not limited to the embodiment as described above. For example, the number of cameras to be installed is not limited to the above number. There may be at least two, but more than this may be used. As the number of cameras increases, the mechanism for driving the cameras can be simplified and imaging can be performed at high speed. The number of detection marks may be at least two.

  The plurality of cameras may be arranged apart from each other so that the positions of the objects held away from each other can be imaged. For example, in the case of an apparatus for laminating workpieces, it is only necessary that the cameras be spaced apart so that the positions of the workpieces that are separated and held for bonding can be detected. Therefore, the case where the camera is arranged in the vertical direction and the case where the camera is arranged on the left and right are included, including cases where the optical axes of the cameras are coincident, parallel, and cases where the angles of the optical axes are different. The plurality of detection marks need only be arranged so as to be imaged by the cameras arranged as described above.

  The modes of the detection jig and the detection mark are not limited to those exemplified in the above embodiment, and any mode is possible as long as the position of the detection mark is fixed. Also good. For example, the detection jig may be formed by a frame. Further, the detection mark may be formed by a groove or printing. The calculation method of the camera position is not limited to the one exemplified in the above embodiment.

10a to 10d ... CCD camera 11, 12 ... arm 13 ... camera drive mechanism 20 ... detection jig 21 ... upper plate 22 ... lower plate 23 ... column 24 ... detection mark 30 ... table 31 ... table drive mechanism 40 ... control device DESCRIPTION OF SYMBOLS 41 ... Camera drive part 42 ... Imaging control part 43 ... Image processing part 44 ... Mark extraction part 45 ... Table drive part 46 ... Camera position calculation part 47 ... Memory | storage part

Claims (7)

Multiple cameras,
A detection jig for detecting the installation position of the camera;
A detection mark provided on the detection jig;
Displacement means for displacing the position of the detection jig within a range where the detection mark is within the field of view of the camera;
Position calculating means for calculating the position of the camera based on detection marks captured by the camera at a plurality of different positions by displacing the detection jig by the displacement means;
A camera installation position detecting device characterized by comprising:   2. The camera installation position detection apparatus according to claim 1, wherein the displacement means has a drive mechanism for rotating the detection jig.   2. The camera installation position detection device according to claim 1, wherein when at least two of the detection marks are projected in an optical axis direction of the camera, a positional relationship viewed from a plane direction is fixed.   4. The camera installation position detection apparatus according to claim 3, wherein at least two of the detection marks are arranged at positions overlapping when projected in the optical axis direction of the camera. The detection mark provided on the detection jig is imaged at least twice by changing the position by a plurality of cameras,
A camera installation position detection method, comprising: calculating a camera position based on a position of a detection mark imaged by the camera. In the camera installation position detection jig for detecting the installation positions of multiple cameras,
A camera installation position detection jig, wherein a positional relationship of at least two detection marks picked up by a camera when viewed from a plane direction is fixed.   7. The camera installation position detection jig according to claim 6, wherein at least two of the detection marks are arranged at positions overlapping when projected in the optical axis direction of the camera.

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