Method for measuring the amount of deviation, measuring apparatus, and program

Abstract

To provide a measurement method, measurement device and program which can measure a deviation amount of an installation angle relative to the reference direction of an axis of a camera for imaging an imaging body and highly accurately correct a deviation of the installation angle at a low cost.SOLUTION: A measurement method using a measurement device for measuring a deviation amount of an installation angle relative to the reference direction of an axis of a camera comprises: an imaging step of imaging a target given with a reference index that can specify a straight line with known inclination in different visual fields plural times; an image processing step of obtaining the straight line specified on the basis of the reference index correspondingly to the respective reference indexes in images captured in the different visual fields; and a calculation step of calculating a rotation angle at which the distance between the plurality of straight lines becomes 0 as a deviation amount of the installation angle.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a method for measuring a deviation amount, a measuring device, and a program.

Background Art

[0002] Conventionally, an accuracy measuring device for an aligner that aligns the posture of a semiconductor wafer is known. The accuracy measuring device includes imaging means for imaging a pair of marks provided at a predetermined interval on a measurement surface of a wafer for accuracy measurement that is detachably attached to a reference index on a wafer mounting table, when the wafer is on the reference index and when the wafer is aligned in posture by the aligner, and an image processing device for measuring the accuracy of the aligner based on the image information obtained from each imaging (see, for example, Patent Document 1).

[0003] Also, an electronic component mounting device including a component mounting head, a camera for acquiring an image of an electronic component, and an image processing unit that performs distortion correction on the acquired image of the electronic component based on distortion correction data and recognizes the position of the electronic component based on the image on which the distortion correction has been performed is also known. Regarding a method for correcting image distortion caused by camera posture and lens distortion that occurs in the camera for component position recognition of the electronic component mounting device, angular deviation can be detected by imaging a distortion correction jig provided with a dot chart (see, for example, Patent Document 2). In addition, a calibration method for calibrating the deviation in the optical axis direction of a stereo camera including a first camera and a second camera fixed by a camera support is also known. In this calibration method, a calibration chart is imaged, and correction data can be created by comparing the coordinates of the output lattice points with the ideal coordinates having no deviation held in advance (see, for example, Patent Document 3).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

[0005] For example, when imaging an object by moving the camera parallel to an axis, or when imaging an object being transported by a belt conveyor with the camera fixed to an axis, there is a risk that the angle of the image may be shifted due to a shift in the camera's installation angle. Patent documents 1 to 3 disclose methods for imaging an object with a camera and correcting the angle of the image that occurs during imaging. To improve the accuracy of this correction, there are methods for mounting the camera with high precision relative to the axis, but introducing such methods leads to increased costs. Furthermore, patent documents 1 to 3 also describe, for example, a software-based correction method in which the camera images the object once and detects the shift in the camera's installation angle using only one field of view, but currently, high measurement accuracy cannot be expected with this detection method.

[0006] This invention has been made in view of the above-mentioned problems, and its ultimate objective is to provide a measurement method, a measuring device, and a program that can measure the amount of deviation in the installation angle of the camera axis for imaging an image object with respect to the reference direction, and correct the deviation in the installation angle at low cost and with high accuracy. In the following application examples and embodiments, the measurement method, measuring device, and program refer to the measurement method, measuring device, and program for measuring the amount of deviation in the installation angle of the camera axis with respect to the reference direction. [Means for solving the problem]

[0007] This disclosure aims to solve the above problems, A measurement method for measuring the amount of deviation in the installation angle of a camera mounted on a support with respect to a predetermined reference direction of the support, A target object is used that has a reference indicator attached to it that can identify a straight line that is parallel to or at a predetermined angle with respect to the aforementioned reference direction. The imaging step involves moving the camera or the target object along the reference direction to image the target object multiple times in different fields of view, An image processing step to determine the straight line identified based on the reference index, corresponding to each of the reference indexes in the images captured in the different fields of view, The measurement method includes a calculation step of calculating the rotation angle at which the distance between a plurality of the aforementioned straight lines becomes zero as the amount of deviation of the installation angle.

[0008] In the imaging process, by imaging the target object with a reference index multiple times from different fields of view, the rotation angle can be calculated with high accuracy as the amount of deviation in the installation angle in the calculation process. Therefore, the amount of deviation in the installation angle measured by the above measurement method is highly reliable, and if the amount of deviation in the installation angle can be accurately determined, the deviation in the installation angle can be corrected with high accuracy by manual or automatic means. In addition, the above measurement method is simple and the deviation in the installation angle can be corrected at low cost. The predetermined angle mentioned above is the angle of the target object relative to the reference direction when the target object is installed in a position that is not parallel to the reference direction. Whether the target object is installed parallel to the reference direction or not, the rotation angle can be calculated as the amount of deviation in the installation angle in the calculation process.

[0009] Furthermore, the present disclosure may also provide a measurement method characterized by further comprising a display step that displays data relating to at least one of the following: the reference index for each of the images captured in the different fields of view during the imaging step, the straight line obtained in the image processing step, and the rotation angle calculated in the calculation step. This allows for visual and numerical confirmation of whether a deviation in the installation angle has occurred and the amount of the deviation in the installation angle.

[0010] Furthermore, the present disclosure may also provide a measurement method characterized by further comprising a communication step of transmitting data relating to at least one of the reference index for each of the images captured in the different fields of view during the imaging step, the straight line obtained during the image processing step, and the rotation angle calculated during the calculation step, and receiving information relating to the amount of deviation of the installation angle based on said data. With this method, it is possible to transmit to an external device whether a deviation in the installation angle has occurred and the amount of the deviation in the installation angle, and to receive feedback from experts, for example, on how to take measures to improve the deviation in the installation angle.

[0011] Furthermore, the present disclosure may also provide a measurement method characterized by further comprising: a determination step of determining whether the contamination in the reference index exceeds a predetermined threshold; and, if the contamination exceeds the predetermined threshold, a notification step of notifying the location of the contamination, the rank of the contamination, and a corresponding method of action according to the rank. Contamination in the reference index can make it difficult to accurately recognize the reference index in the image processing step, which may reduce the accuracy of calculating the rotation angle in the calculation step. This method allows for accurate understanding of information related to the contamination and suppresses the risk of reduced accuracy in calculating the rotation angle.

[0012] Furthermore, in this disclosure, the measurement method may also be characterized in that, in the judgment step, the stain is determined by the ratio of black pixels to white pixels of the reference index. With this method, since the stain is determined by the ratio of black pixels to white pixels, optical inspection is easily applied.

[0013] Furthermore, the present disclosure may also provide a measurement method that further comprises: a second calculation step of calculating the difference between the amount of deviation in the installation angle and a predetermined standard value, or periodically calculating the amount of deviation in the installation angle; and a second notification step of issuing a warning if the difference between the amount of deviation in the installation angle and the predetermined standard value, or the amount of deviation in the installation angle, is greater than or equal to a predetermined certain value. This method allows for the rapid detection of deviations in the installation angle.

[0014] Furthermore, in this disclosure, the measurement method may also be characterized in that, in the calculation step, the rotation angle corresponding to each of the multiple cameras is calculated, and the average value of all the rotation angles is calculated as the amount of deviation of the installation angle. This allows for measurement of the amount of deviation of the installation angle with higher reliability.

[0015] Furthermore, in this disclosure, the measurement method may also be characterized in that the reference indicator is a figure arranged in a straight line on the target object. Examples of such figures include dots and crosses, which broadens the range of variations when designing the reference indicator.

[0016] Furthermore, in this disclosure, the measurement method may also be characterized in that the reference indicator is a straight line drawn on the target object. This broadens the range of variations when designing the reference indicator. Also, it makes it easier to determine the straight line in the image processing step.

[0017] Furthermore, in this disclosure, the measurement method may also be characterized in that the reference indicator is a straight line projected onto the target object. For example, projection using a laser or the like is possible, which makes it easy to project a reference indicator with accurate dimensions onto the target object.

[0018] Furthermore, in this disclosure, the measurement method may also be characterized in that the reference indicator is a component arranged linearly on the target object, or a linear structure formed on the target object. Examples of components arranged linearly on the target object include LED light-emitting elements, which make it easy to form a reference indicator with accurate dimensions on the target object.

[0019] Furthermore, in this disclosure, each step in the above measurement method may be a program for causing a measuring device to perform the steps.

[0020] Furthermore, this disclosure is, A measuring device that includes a camera installed on a support and measures the amount of deviation in the installation angle with respect to a predetermined reference direction of the support, a target object with a reference indicator that can identify a straight line parallel to the reference direction or having a predetermined angle is used, after imaging the target object multiple times in different fields of view by moving the camera or the target object along the reference direction, an image processing unit that obtains a straight line specified based on the reference indicator corresponding to each of the reference indicators in the images taken in the different fields of view acquired from the camera, a calculation unit that calculates the rotation angle at which the distance between the plurality of straight lines becomes zero as the amount of deviation in the installation angle, characterized by including a measuring device.

[0021] By the camera imaging a target object with a reference indicator multiple times in different fields of view, the calculation unit can calculate the rotation angle as the amount of deviation in the installation angle with high precision. Therefore, the amount of deviation in the installation angle measured by the above measuring device is highly reliable. If the amount of deviation in the installation angle can be accurately grasped, the deviation in the installation angle can be corrected with high precision by manual or automatic means. Also, the configuration of the above measuring device is simple, and the deviation in the installation angle can be corrected at low cost. Note that whether the target object is installed parallel to the reference direction or in a non-parallel state, the calculation unit can calculate the rotation angle as the amount of deviation in the installation angle and calculate it.

[0022] Also, in the present disclosure, it may be a measuring device further including a display unit that displays data related to at least one of each of the reference indicators in the images taken by the camera in the different fields of view, the straight line obtained by the image processing unit, and the rotation angle calculated by the calculation unit. By the display unit displaying the data, it is possible to visually and numerically grasp the occurrence of a deviation in the installation angle and the amount of deviation in the installation angle.

[0023] Furthermore, the present disclosure may also provide a measuring device that further includes a communication unit that transmits data relating to at least one of the reference index for each of the images captured by the camera in the different fields of view, the straight line determined by the image processing unit, and the rotation angle calculated by the calculation unit, and receives information relating to the amount of deviation of the installation angle based on said data. With this, it is possible to transmit to an external device whether a deviation in the installation angle has occurred and the amount of the deviation in the installation angle, and to receive feedback from experts, for example, on how to take measures to improve the deviation in the installation angle.

[0024] Furthermore, in this disclosure, the measuring device may be characterized in that, when the communication unit transmits the data and receives information relating to the amount of deviation in the installation angle, the display unit displays that the deviation in the installation angle has been calibrated. This ensures the effectiveness and safety of the measuring device and guarantees the high accuracy of the measuring device.

[0025] Furthermore, the present disclosure may also provide a measuring device that further includes a determination unit that determines whether the contamination in the reference indicator exceeds a predetermined threshold, and a notification unit that, if the contamination exceeds the predetermined threshold, notifies the location of the contamination, the rank of the contamination, and a corresponding method of action. This allows for accurate acquisition of information related to contamination in the reference indicator and suppresses the risk of a decrease in the accuracy of calculating the rotation angle due to contamination.

[0026] Furthermore, in this disclosure, the determination unit may be a measuring device characterized by determining the dirt based on the ratio of black pixels to white pixels of the reference index. With this, since the dirt is determined by the ratio of black pixels to white pixels, optical inspection is easily applied.

[0027] Furthermore, the present disclosure may also provide a measuring device that further comprises: a second calculation unit that calculates the difference between the amount of deviation in the installation angle and a predetermined standard value, or that periodically calculates the amount of deviation in the installation angle; and a second notification unit that issues a warning if the difference between the amount of deviation in the installation angle and the predetermined standard value, or the amount of deviation in the installation angle, is greater than or equal to a predetermined constant value. This allows for quick detection of deviations in the installation angle.

[0028] Furthermore, in this disclosure, the calculation unit may be a measuring device characterized by calculating the rotation angle corresponding to each of the multiple cameras and calculating the average value of all the rotation angles as the amount of deviation of the installation angle. This allows for measurement of the amount of deviation of the installation angle with higher reliability.

[0029] Furthermore, in this disclosure, the reference indicator may be a measuring device characterized by being a figure arranged in a straight line on the target object. This broadens the range of variations in the figure when designing the reference indicator.

[0030] Furthermore, in this disclosure, the reference indicator may be a measuring device characterized by being a straight line drawn on the target object. According to this, when designing the reference indicator, This broadens the range of possibilities. Furthermore, image processing makes it easier to find straight lines.

[0031] Furthermore, in this disclosure, the reference indicator may be a measuring device characterized by being a straight line projected onto the target object. This makes it easier to project a reference indicator with accurate dimensions onto the target object.

[0032] Furthermore, in this disclosure, the reference indicator may be a measuring device characterized by being a component arranged linearly on the target object, or a linear structure formed on the target object. This makes it easier to form a reference indicator with accurate dimensions on the target object.

[0033] Furthermore, the present disclosure may also describe a measuring device that automatically detects deviations in the installation angle at startup. This allows for periodic and automatic maintenance of deviations in the installation angle.

[0034] Furthermore, in this disclosure, the computer may be a program for causing it to function as the above-mentioned measuring device.

[0035] Furthermore, this disclosure can be interpreted as a measurement method that includes at least a part of the processing performed by the above means. It can also be interpreted as a measurement device that includes at least a part of the above means. Furthermore, it can be interpreted as a computer program that causes a computer to execute each step of these methods, or as a computer-readable storage medium that non-temporarily stores said program.

[0036] Furthermore, the means for solving the above problems can be used in combination with each other as much as possible. [Effects of the Invention]

[0037] According to the present invention, a method, measuring apparatus, and program for measuring the amount of deviation in the installation angle of a camera axis relative to a reference direction make it possible to measure the amount of deviation and correct the deviation in the installation angle at low cost and with high accuracy. [Brief explanation of the drawing]

[0038] [Figure 1] Figure 1 shows an example of the hardware configuration of the measuring device according to the embodiment. [Figure 2] Figure 2 illustrates the problems that may arise when imaging an object using the camera in the measuring device according to the embodiment, and a measurement method for solving those problems. [Figure 3] Figure 3 is a functional block diagram showing an example of a measuring device according to the embodiment. [Figure 4]Figure 4A is a first explanatory diagram showing a method for measuring the amount of deviation in the installation angle relative to the camera's movement axis using the measuring device according to the embodiment. Figure 4B is a second explanatory diagram showing a continuation of Figure 4A. [Figure 5] Figure 5 is a third explanatory diagram that continues from Figure 4B. [Figure 6] Figure 6 is an explanatory diagram showing an example of the content transmitted and received by the communication unit in the measuring device according to the embodiment. [Figure 7] Figure 7 is a flowchart showing the procedure for the measurement method using the measuring device according to the embodiment. [Modes for carrying out the invention]

[0039] [Examples of application] The following outlines some examples of applications of this disclosure, using some drawings. This disclosure can be applied to a measuring device 1 as shown in Figure 1. Furthermore, by using the measuring device 1, this disclosure can be applied to the methods shown in the explanatory diagrams from Figures 4A to 5.

[0040] Figure 1 shows an example of the hardware configuration of a measuring device 1 to which this disclosure can be applied. In this application example, the measuring device 1 is configured by interconnecting a camera 10, a control device 11, a data management server 12, and a User Interface (UI) 13 via a wireless or wired communication line.

[0041] The control device 11 generates an image of the imager from the imager captured by the camera 10 and processes the image using a pre-registered inspection program to determine whether the condition of the imaged area on the imager is good or bad. The control device 11 includes, for example, a processor such as a CPU, a storage device such as RAM or ROM, and an interface with external devices as part of its hardware configuration. The control device 11 provides the functions shown in Figure 3 below by having the CPU execute a program stored in the storage device. Some or all of the above functions may be implemented by hardware circuits such as ASICs (Application Specific Integrated Circuits) or FPGAs (Field Programmable Gate Arrays). Details of each of these functional parts will be explained in the functional block diagram in Figure 3.

[0042] Furthermore, as an example of an imaging element, in this application example, an imaging location 21 (shown in Figure 2) on the printed circuit board 2 is used as an example. The imaging location 21 could be, for example, wiring or via holes on the printed circuit board 2. In this application example, the camera 10 is used to image the imaging location 21 on the printed circuit board 2 as it is transported in the direction of the arrow shown in Figure 1 by a transport line (not shown), but the imaging location 21 may also be imaged with the printed circuit board 2 fixed.

[0043] Furthermore, the control device 11 may perform controls on the camera 10 and the lighting (not shown) that illuminates the printed circuit board 2, such as changing the F-number of the camera 10's optical system, changing the brightness of the lighting, and calibrating the camera 10 and the lighting.

[0044] The data management server 12 stores multiple types of data, including the inspection program mentioned above, inspection items and inspection standards for each imaging location 21, and various other information necessary for processing in the UI 13.

[0045] Figure 2 illustrates a problem that may arise when imaging an object using the camera 10 in a measuring device 1 to which this disclosure is applicable, and a measurement method for solving that problem. Figure 2 is also a schematic diagram of the manner in which the camera 10 images an object, viewed from above. The camera 10 is mounted on a roughly rectangular plate (not shown) attached to the moving axis 3 so as to be movable along the longitudinal direction of the moving axis 3 (hereinafter referred to as the reference direction). However, when mounting the camera 10 on the plate (hereinafter, including the plate, referred to as the moving axis 3), the reference axis of the image captured using the camera 10 is often not fixed so as to be parallel to the reference direction of the moving axis 3, and a deviation in the mounting angle of the camera 10 with respect to the moving axis 3 often occurs by θ as shown in Figure 2. When a deviation in the mounting angle occurs, a deviation naturally occurs in the imaging field of view of the camera 10 (shaded area shown in Figure 2), and the analysis of the obtained image becomes difficult due to this deviation. To correct the deviation amount θ of the installation angle, that is, to bring θ closer to the ideal value of 0, in this application example, the deviation amount θ of the installation angle is measured using the functions of the measuring device 1 as shown in the functional block diagram of Figure 3 below. The specific method will be explained in the explanatory diagrams from Figures 4A to 5 below. Here, the moving axis 3 corresponds to the support in this disclosure.

[0046] Figure 3 is a functional block diagram showing an example of a measuring device 1 to which this disclosure can be applied. The control device 11 of the measuring device 1 in this application example is broadly composed of an image processing unit 110 and a calculation unit 111, etc. In measuring the amount of deviation θ of the installation angle shown in Figure 2 (hereinafter, the installation angle shown in Figure 2 is simply referred to as the installation angle), the following dots are used as shown in Figures 4A to 5. Use jig 4 with charts 41 and 42 attached.

[0047] To measure the amount of deviation θ of the installation angle, first, the dot charts 41 and 42 are imaged using the camera 10. At this time, the jig 4 is imaged multiple times in different fields of view by moving the camera 10 along the reference direction of the movement axis 3, or by moving the jig 4 to which the dot charts 41 and 42 are attached while the camera 10 is fixed. The image processing unit 110 acquires the images captured from the camera 10 in different fields of view and finds a straight line passing through the dot charts 41 and 42, corresponding to each of the dot charts 41 and 42 in the captured image 5. The slope of this straight line may be known. The calculation unit 111 calculates the amount of deviation θ of the installation angle as the rotation angle at which the distance between the multiple calculated straight lines becomes 0. Details will be explained in order in the explanatory diagrams from Figure 4A to Figure 5.

[0048] Figure 4A is a first explanatory diagram showing a method for measuring the amount of deviation θ of the installation angle using a measuring device 1 to which this disclosure is applicable. As described above, first, the camera 10 is moved by a distance L along the reference direction of the moving axis 3, and the jig 4 with dot charts 41 and 42 attached is imaged multiple times in different fields of view. In this application example, images are taken twice in different fields of view, but the number of times is not limited to this. Note that in Image 1 and Image 2 in Figure 4A, the jig 4, which is the imaging body, is the same, and different dot charts 41 and 42 on the same jig 4 are imaged in different fields of view. The dimensions of the dot charts 41 and 42 are known in advance, and in Image 1 and Image 2, a group of dots arranged in the longitudinal direction (reference direction) of the jig 4 are the dot charts 41 and 42. Note that Image 1 and Image 2 may contain other things as long as they contain the dot charts 41 and 42. In Image 1 and Image 2, the dot charts 41 and 42 are arranged to be aligned on the same straight line. Furthermore, when installing the jig 4, the longitudinal direction of the jig 4 may or may not be parallel to the reference direction of the moving axis 3. In this disclosure, the predetermined angle is the angle of the longitudinal direction of the jig 4 with respect to the reference direction of the moving axis 3 when the jig 4 is installed in a state where its longitudinal direction is not parallel to the reference direction of the moving axis 3. Here, the jig 4 corresponds to the target object in this disclosure. Also, the dot charts 41 and 42 correspond to the reference indicators in this disclosure.

[0049] Figure 4B is a second explanatory diagram showing a continuation of Figure 4A. The image processing unit 110 considers the reference direction of the movement axis 3 as the x-axis and rotates images 1 and 2 so that the two arrows (the two arrows shown in Figure 4A) along the shorter directions of each image are perpendicular to the x-axis, that is, so that the two arrows can be considered as the y-axis. After rotation, straight lines (y=ax+b1, y=ax+b2) passing through dot charts 41 and 42 are found. Since these two straight lines have the same slope and are parallel to each other, they are separated by a distance p in the y-axis direction at any point. The equations of the two straight lines are found based on the value of the distance L.

[0050] Figure 5 is a third explanatory diagram showing a continuation of Figure 4B. Since the two lines are parallel to each other, if each line is rotated in opposite directions by the same angle, the two lines will coincide. The rotation angle φ at this point of coincidence geometrically corresponds to the amount of deviation θ in the installation angle. That is, the calculation unit 111 rotates image 1 and image 2 in opposite directions so that the distance p becomes 0, and calculates the rotation angle φ at this time as the amount of deviation θ in the installation angle.

[0051] As described above, by using the functions of the measuring device 1 as shown in the functional block diagram of Figure 3 and performing the method shown in the explanatory diagrams of Figures 4A to 5, it is possible to measure the amount of deviation θ of the installation angle at low cost and with high accuracy. In this application example, the example of setting up the jig 4 with its longitudinal direction parallel to the reference direction of the moving axis 3 has been described. In contrast, if the jig 4 is set up with its longitudinal direction not parallel to the reference direction of the moving axis 3, the slope a in the equations of the two lines (y=ax+b1, y=ax+b2) will change. However, even in this case, the slopes of the two lines remain equal. However, they remain parallel to each other, and it is possible to calculate the amount of deviation θ of the installation angle, just as when the jig 4 is installed with its longitudinal direction parallel to the reference direction of the moving axis 3.

[0052] [Examples] The measurement method, measuring apparatus 1, and program according to the embodiments of this disclosure will be described in more detail below with reference to drawings (including drawings that were previously explained in the above application examples). However, the measurement method, measuring apparatus 1, and program according to the embodiments of this disclosure are not intended to be limited to the following configurations.

[0053] <Functional Configuration> Now, let's return to the explanation of Figure 3. Since the measuring device 1 according to this embodiment has the same configuration as the measuring device 1 described in the application example, a detailed explanation of the contents described in the application example will be omitted. In addition, in this specification, the same reference numerals are used to describe the same components.

[0054] The UI13 of the measuring device 1 in this embodiment is broadly composed of a display unit 130 and a communication unit 131, etc. The display unit 130 is, for example, a monitor or display, and can visualize and display images captured by the camera 10 (images 1 and 2 shown in Figure 4A), two straight lines obtained by the image processing unit 110, and data related to the rotation angle φ calculated by the calculation unit 111. The display unit 130 can display the contents shown in the explanatory diagrams from Figures 4A to 5, but it is not necessary to have the function to display all of them. For example, if the contents are as shown in Figure 4B, the display unit 130 only needs to display images 1 and 2, and the two straight lines do not need to be displayed. Also, since it is sufficient to know the rotation angle φ, the display unit 130 may only display the contents shown in Figure 5.

[0055] The communication unit 131 can automatically transmit images captured by the camera 10, two straight lines determined by the image processing unit 110, and data related to the rotation angle φ calculated by the calculation unit 111 to pre-configured or manually entered destinations. It can also receive information related to the amount of deviation θ of the installation angle based on the transmitted data from the destination. A specific example is shown in Figure 6 below.

[0056] Furthermore, the UI13 may include an input unit (not shown) for inputting information to the control device 11, such as a keyboard or mouse. The control device 11 may also be configured to include the UI13.

[0057] Furthermore, the control device 11 may also be configured to include a determination unit 112 and a notification unit 113. If, for example, foreign matter or other dirt is attached to the dot charts 41 and 42 in images 1 and 2 (images 1 and 2 shown in Figure 4B) acquired by the image processing unit 110, it may become difficult to accurately recognize the dot charts 41 and 42, and the accuracy of the calculation unit 111 in calculating the rotation angle φ may decrease.

[0058] The determination unit 112 determines whether the amount of dirt on the dot charts 41 and 42 exceeds a predetermined threshold in images 1 and 2 acquired by the image processing unit 110. The criteria for determining dirt include, for example, the ratio of black pixels to white pixels in the dot charts 41 and 42. If this ratio exceeds a predetermined threshold, the determination unit 112 determines that dirt is present on the dot charts 41 and 42. The notification unit 113 has an alarm function, such as a siren, and if the amount of dirt on the dot charts 41 and 42 exceeds a predetermined threshold, it notifies the unit of, for example, the location of the dirt, the rank of the dirt, and the appropriate response method based on the rank. Furthermore, the content notified by the notification unit 113 is displayed on the display unit 130 or transmitted to an external device by the communication unit 131. You can send it.

[0059] The control device 11 may also be configured to further include a second calculation unit 114 and a second notification unit 115. The second calculation unit 114 calculates the difference between the amount of deviation θ of the installation angle and a predetermined standard value, or periodically calculates the amount of deviation θ of the installation angle. At this time, the second calculation unit 114 may be based on data acquired from the image processing unit 110, or on past data acquired from the image processing unit 110 stored in the data management server 12, or on data acquired directly from the camera 10. The second notification unit 115 notifies a warning if the difference between the amount of deviation θ of the installation angle and a predetermined standard value, or if the amount of deviation θ of the installation angle is greater than or equal to a predetermined constant value. As a means of notifying a warning, for example, there is a means of outputting an error message such as "camera installation angle outside standard" or "amount of change in camera installation angle outside standard value". Furthermore, if the difference between the deviation amount θ of the installation angle and a predetermined standard value, or if the deviation amount θ of the installation angle is less than a predetermined constant value, a notification may be made indicating that there is no problem with the deviation in the installation angle. In addition, the content of the notification by the second notification unit 115 may be displayed by the display unit 130 or transmitted to an external device by the communication unit 131.

[0060] Alternatively, if the measuring device 1 is configured with multiple cameras 10, the calculation unit 111 may calculate the rotation angle φ corresponding to each of the multiple cameras 10 and calculate the average value of all rotation angles φ as the deviation amount θ of the installation angle. Furthermore, the measuring device 1 may be equipped with a function to automatically detect the deviation of the installation angle θ when it is started up.

[0061] <Measurement method> Now, let's return to the explanation of Figures 4A to 5. When measuring the deviation amount θ of the installation angle, a jig 4 with numerous dots arranged in a straight line, including dot charts 41 and 42, was used, but the type of jig 4 is not limited to these. For example, the shapes attached to jig 4 are not limited to dots, but may also be crosses, squares, etc. Also, instead of dot charts 41 and 42, straight lines drawn with high precision on jig 4, such as a square chart, may be used. In addition, straight lines projected onto jig 4 via a medium such as a laser, or components such as LED light-emitting elements arranged in a straight line on jig 4 may be used. Furthermore, these indicators may be formed directly on the measuring device 1 instead of on jig 4. Moreover, straight structures formed on the measuring device 1 or as indicators may be used. Examples of these structures may include rails that constitute the moving axis 3.

[0062] Figure 6 is an explanatory diagram showing an example of the content transmitted and received by the communication unit 131 in the measuring device 1 according to the embodiment. In summary, the communication unit 131 transmits data to experts related to the measuring device 1 (such as the designer, manufacturer, or manager of the measuring device 1), the experts perform measurements and make judgments based on the data, and the communication unit 131 receives information related to the amount of deviation θ of the installation angle based on the data.

[0063] The data transmitted by the communication unit 131 to the expert may include, for example, images of the dot charts 41 and 42 captured by the camera 10, two straight lines obtained by the image processing unit 110 (or just the equations of each line), the rotation angle φ calculated by the calculation unit 111, as well as data related to the inspection performance of the measuring device 1, or photographs of the external appearance of the measuring device 1 or the jig 4. For example, if the transmitted data is images of the dot charts 41 and 42 or two straight lines, the expert can calculate the rotation angle φ based on that data and feed back the rotation angle φ as the calculation result. If the transmitted data is the rotation angle φ, and if the rotation angle φ is close to 0, the expert can determine that there is no problem with the installation of the camera 10 relative to the moving axis 3. Otherwise, they can suggest manually correcting the misalignment of the installation angle as a way to deal with the error. If the transmitted data is a photograph of the external appearance of the measuring device 1, the expert can check the deterioration of the measuring device 1 over time and suggest maintenance measures as a way to deal with the error. If the data is a photograph of jig 4, the dirt on the dot charts 41 and 42 can be visually inspected, suggesting that jig 4 should be cleaned.

[0064] Furthermore, when the communication unit 131 transmits the above data to a specialist and receives information from the specialist regarding the deviation amount θ of the installation angle based on the above data, it may also receive a calibration certificate and the expiration date of the calibration certificate as proof that the deviation of the installation angle has been calibrated. At this time, the display unit 130 may display the calibration certificate and the expiration date of the calibration certificate, and the calibration certificate and the expiration date of the calibration certificate may be made renewable. In addition, the display unit 130 may display a message indicating that the expiration date of the calibration certificate is approaching or has expired.

[0065] <Flowchart> Figure 7 is a flowchart illustrating the procedure for a measurement method using the measuring device 1 according to an embodiment. In this flowchart, first, the jig 4 is imaged twice in different fields of view by moving the camera 10 along the reference direction of the moving axis 3, or by moving the jig 4 with the dot charts 41 and 42 attached while the camera 10 is fixed (S101). At this time, the images are taken so that the dot charts 41 and 42 are included in each image. The number of times images are taken may be more than two. Here, S101 corresponds to the imaging step in this disclosure and Figure 4A in this embodiment. Next, the image processing unit 110 acquires images from the camera 10 in different fields of view and determines two straight lines passing through the dot charts 41 and 42, corresponding to the dot charts 41 and 42 in each of the images (S102). The two straight lines are parallel to each other and are separated by a certain distance in a predetermined direction at any point. Here, S102 corresponds to the image processing step in this disclosure and Figure 4B in this embodiment. Next, the calculation unit 111 rotates each of the images captured in different fields of view in opposite directions so that the constant distance between the two lines becomes 0, that is, so that the two lines overlap and coincide, and calculates the rotation angle φ at this time as the amount of deviation θ of the installation angle (S103). Here, S103 corresponds to the calculation step in this disclosure and to Figure 5 in this embodiment.

[0066] Furthermore, the display unit 130 can visualize and display images captured in different fields of view during the imaging process S101, two straight lines obtained in the image processing process S102, and data related to the rotation angle φ calculated in the calculation process S103 (S104). Here, S104 corresponds to the display process in this disclosure. The communication unit 131 can automatically transmit images captured in different fields of view during the imaging process S101, two straight lines obtained in the image processing process S102, and data related to the rotation angle φ calculated in the calculation process S103 to a pre-set or manually entered transmission destination. It can also receive information related to the amount of deviation θ of the installation angle based on the transmitted data from the transmission destination (S105). Here, S105 corresponds to the communication process in this disclosure and to Figure 6 in this embodiment.

[0067] Furthermore, the determination unit 112 determines whether the amount of dirt on the dot charts 41 and 42 exceeds a predetermined threshold in the image acquired in the image processing step S102 (S106). If the amount of dirt exceeds the predetermined threshold (S106: yes), the determination unit 112 determines that dirt is attached to the dot charts 41 and 42. In this case, the notification unit 113 notifies the location of the dirt, the rank of the dirt, and the appropriate response method according to this rank (S107). Here, S106 corresponds to the determination step in this disclosure, and S107 corresponds to the notification step in this disclosure. If the amount of dirt does not exceed the predetermined threshold (S106: no), the notification unit 113 does not function.

[0068] Furthermore, the second calculation unit 114 calculates the difference between the deviation amount θ of the installation angle and a predetermined standard value, or periodically calculates the deviation amount θ of the installation angle (S108). At this time, the second calculation unit 114 may be based on data acquired in the image processing step S102, or on data previously acquired in the image processing step S102 stored in the data management server 12, or on data directly acquired in the imaging step S101. Here, S108 corresponds to the second calculation step in this disclosure. In the second calculation step S108, the second notification unit 115 notifies a warning if the difference between the amount of deviation θ of the installation angle and a predetermined standard value, or if the amount of deviation θ of the installation angle is greater than or equal to a predetermined constant value (S109). Here, S109 corresponds to the second notification step in this disclosure. If the difference between the amount of deviation θ of the installation angle and a predetermined standard value, or if the amount of deviation θ of the installation angle is less than a predetermined constant value, it may be configured to notify that there is no problem with the deviation of the installation angle.

[0069] <Note 1> A measurement method for measuring the amount of deviation in the installation angle of a camera (10) installed on a support (3) with respect to a predetermined reference direction of the support, A target object (4) is used that is marked with reference indicators (41, 42) that can identify a straight line parallel to or at a predetermined angle with respect to the aforementioned reference direction. The imaging step (S101) involves moving the camera or the target object along the reference direction to image the target object multiple times in different fields of view, Image processing step (S102) to determine the straight line identified based on the reference index, corresponding to each of the reference indexes in the images captured in the different fields of view, A measurement method characterized by comprising a calculation step (S103) of calculating the rotation angle at which the distance between a plurality of the aforementioned straight lines becomes 0 as the amount of deviation of the installation angle.

[0070] <Note 2> A measuring device (1) for measuring the amount of deviation of the installation angle of the support with respect to a predetermined reference direction, comprising a camera (10) installed on a support (3), A target object (4) is used that is marked with reference indicators (41, 42) that can identify a straight line parallel to or at a predetermined angle with respect to the aforementioned reference direction. The camera or the target object is moved along the reference direction to capture images of the target object multiple times in different fields of view, and then an image processing unit (110) determines a straight line identified based on the reference index in each of the images captured in the different fields of view acquired from the camera, A measuring device (1) is characterized by comprising a calculation unit (111) that calculates the rotation angle at which the distance between a plurality of the aforementioned straight lines becomes 0 as the amount of deviation of the installation angle. [Explanation of symbols]

[0071] 1: Measuring device 10: Camera 11: Control device 110: Image Processing Unit 111: Calculation Unit 112: Judgment Department 113: Hochi Department 114: Second calculation unit 115: The Second Hochi Department 12: Data management server 13: UI 130: Display section 131: Communications Department 2: Printed circuit board 21: Imaging location 3: Movement axis 4: Jig 41, 42: Dot chart

Claims

1. A measurement method for measuring the amount of deviation in the installation angle of a camera mounted on a support with respect to a predetermined reference direction of the support, A target object is used that has a reference indicator attached to it that can identify a straight line that is parallel to or at a predetermined angle with respect to the aforementioned reference direction. The imaging step involves moving the camera or the target object along the reference direction to image the target object multiple times in different fields of view, An image processing step to determine the straight line identified based on the reference index, corresponding to each of the reference indexes in the images captured in the different fields of view, A measurement method characterized by comprising: a calculation step of rotating an image captured in a different field of view, or the line obtained from said image, so that the multiple lines obtained in the image processing step coincide with each other, and calculating the rotation angle at that time as the amount of deviation of the installation angle.

2. A measuring device comprising a camera mounted on a support, for measuring the amount of deviation of the mounting angle of the support with respect to a predetermined reference direction, A target object is used that has a reference indicator attached to it that can identify a straight line that is parallel to or at a predetermined angle with respect to the aforementioned reference direction. The camera or the target object is moved along the reference direction to capture images of the target object multiple times in different fields of view, and then an image processing unit determines a straight line identified based on the reference index in each of the images captured in the different fields of view acquired from the camera, A measuring device comprising: a calculation unit that rotates images captured in different fields of view, or the lines obtained from such images, so that a plurality of lines obtained by the image processing unit coincide with each other, and calculates the rotation angle at that time as the amount of deviation of the installation angle.

3. The camera relates to at least one of the following in the images captured in the different fields of view: the reference index in each image, the straight line determined by the image processing unit, and the rotation angle calculated by the calculation unit. The measuring device according to claim 2, further comprising a display unit for displaying the data.

4. The measuring device according to claim 2 or 3, further comprising a communication unit that transmits data relating to at least one of the reference index in each of the images captured by the camera in the different fields of view, the straight line determined by the image processing unit, and the rotation angle calculated by the calculation unit, and receives information relating to the amount of deviation of the installation angle based on said data.

5. The camera further comprises a communication unit that transmits data relating to at least one of the reference index in each of the images captured in the different fields of view, the straight line determined by the image processing unit, and the rotation angle calculated by the calculation unit, and receives information relating to the amount of deviation of the installation angle based on said data. The measuring device according to claim 3, characterized in that when the communication unit transmits the data and receives information relating to the amount of deviation in the installation angle, the display unit displays that the deviation in the installation angle has been calibrated.

6. A second calculation unit calculates the difference between the amount of deviation in the installation angle and a predetermined standard value, or periodically calculates the amount of deviation in the installation angle. The measuring device according to any one of claims 2 to 5, further comprising: a second notification unit that issues a warning when the amount of deviation of the installation angle exceeds a predetermined standard value, or when the amount of deviation of the installation angle exceeds a predetermined constant value.

7. The measuring device according to any one of claims 2 to 6, characterized in that the calculation unit calculates the rotation angle corresponding to each of the plurality of cameras and calculates the average value of all the rotation angles as the amount of deviation of the installation angle.

8. The measuring device according to any one of claims 2 to 7, characterized in that the reference indicators are figures arranged in a straight line on the target object.

9. The measuring device according to any one of claims 2 to 7, characterized in that the reference indicator is a straight line drawn on the target object.

10. The measuring device according to any one of claims 2 to 7, characterized in that the reference indicator is a component arranged in a straight line on the target object, or a straight structure formed on the target object.

11. The measuring device according to any one of claims 2 to 10, characterized in that it automatically detects the deviation of the installation angle when it is started.

12. A program for causing a computer to function as a measuring device according to any one of claims 2 to 11.

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