Measuring method and measuring device for measuring objects by x-ray fluorescence

Abstract

To provide a measuring method and measuring device for a measuring object on a measuring table of the measuring device by X-ray fluorescence.SOLUTION: At least one measuring object 27 is placed on a measuring table 21. An overview image of a region of the measuring object on the measuring table is acquired by an optical device. A type of measuring object is determined from the overview image or from an identifier provided on the measuring object or arranged adjacent to the measuring table. The position and / or arrangement of the measuring object on the measuring table is determined from the overview image. A measurement task stored in a data processing device is selected and started for the detected measuring object. Measurement positions P1, P2, P3, P4, and P5 of the measuring object are positioned with measurement points of an X-ray fluorescence device, and at least one measured value is determined. The measuring object measured value is compared with a setting value stored in the data processing device and quality determination result(s) is output.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a method for measuring an object to be measured on a measurement table of a fluorescence X-ray measurement device and a measurement device.

Background Art

[0002] In many fields of industrial production, it is necessary to check and monitor the quality of the object to be measured. In the case of quality control, on the one hand, material analysis can be performed. On the other hand, the measurement of the coating of the object to be measured, particularly the coating thickness, can be formed based on the quality check. In general, the fluorescence X-ray method is known to be used to determine the layer thickness and analyze the coating or the material of the object to be measured. In this process, primary radiation is directed from the radiation source of the fluorescence X-ray device towards the measurement point on the measurement table. An object to be measured is placed or mounted at the measurement point on the measurement table. Secondary radiation emitted from the measurement surface of the object to be measured is detected by the detector of the fluorescence X-ray device, and the detection result is transmitted to a control device or an evaluation device.

[0003] According to the radiation protection regulations, such a measurement device needs to close the measurement chamber while the object to be measured is being measured. Therefore, such a measurement device has a housing cover or a housing opening that can be opened and closed to allow access to the object to be measured in the measurement chamber.

[0004] When performing a quality check, the object to be measured is manually placed on the measurement table at a predetermined position and arrangement in order to approach each measurement point of the object to be measured for measurement. Such a quality check takes time due to the predetermined arrangement of the object to be measured on the measurement table.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The object of the present invention is to propose a method for measuring at least one object on the measuring table of a measuring device using fluorescent X-rays, and a measuring device for carrying out this method, thereby enabling efficient quality control of the object to be measured. [Means for solving the problem]

[0006] The objective is to achieve a method by which an optical device captures an overview image of at least one area of ​​a measurement table on which an object to be measured is placed, wherein the type of object to be measured is determined from the overview image or from an identifier provided on or adjacent to the at least one object to be measured, the position of the at least one object to be measured and / or the placement of the at least one object to be measured on the measurement table is determined from the overview image, a measurement task stored in a data processing device by the control device is selected for the at least one detected object to be measured, is started for the at least one detected object to be measured, at least one measurement position of the at least one object to be measured is located at the measurement point of the X-ray fluorescence device, a measurement value is detected from the at least one measurement position of the object to be measured, and the at least one measurement value is the at least one measurement value. The object to be measured is compared with a set value stored in the data processing device, and a measurement result for at least one measurement position of the at least one object to be measured is output.

[0007] By identifying the objects to be measured, one or more objects can be arbitrarily placed on the measuring table of the measuring device. This can be done manually or by a handling device. This arbitrary placement and / or placement of at least one object on the measuring table allows for time savings when placing the measuring table. Then, at least one object is optically detected by the overview image and recognized according to its type, or detected by an identifier assigned to the object. The position and / or placement of at least one object can also be determined from the overview image, and thus all prerequisites exist for subsequent automated measurement, in which one or more measurement positions of at least one object are sequentially aligned with the measurement points on the measuring table of the measuring device in order to obtain and evaluate measurements from various measurement positions of the object by emitted secondary radiation. By comparing the measurements obtained from at least one measurement position of at least one object with stored nominal values, the measurement results can be output and displayed as to whether they are inside or outside a value range used as a criterion for quality checks.

[0008] Preferably, an overview image of the entire measurement table, positioned in a measurement chamber inside a closed housing, is provided. In this way, the optical device can acquire all the objects to be measured on the measurement table in a single image. At the same time, the position and / or placement of at least one object to be measured on the measurement table can be determined by an image evaluation algorithm.

[0009] In particular, when an identifier placed on the measurement table or an identifier attached to the object being measured is recognized, the system is required to read the identifier and start and execute the measurement task stored in that identifier. Such identifiers can be, for example, QR codes, barcodes, etc.

[0010] Furthermore, it may be advantageous to assign a tolerance range to each subsequent measurement task, within which one or more measurement locations on the object being measured can be queried. Depending on the measurement task or quality requirements, it is possible to choose to increase or decrease the tolerance range. For example, the same tolerance range can be assigned to several measurement locations, or a different tolerance range that deviates from these can be assigned to yet another measurement location on the same object. This allows for quality checks tailored to the function of the object being measured.

[0011] In particular, the coordinate system of the object being measured is provided to be determined from the position and / or arrangement of at least one object being measured. The coordinates of the object being measured coordinate system are converted to the coordinate system of the measuring table. In this way, the control device can control the movement of the measuring table in the X and / or Y directions of the measuring table surface, and the individual measurement positions of the objects being measured can be aligned in a defined manner with respect to the measurement points where the primary radiation of the X-ray fluorescence apparatus is placed.

[0012] Advantageously, after obtaining measurements from at least one measurement location on the object being measured, the system provides an output indicating whether the measurements are good or bad. This allows the operator to easily see which object on the measuring table should be rejected as defective. Furthermore, it can output which measurement locations on the object are outside the acceptable range. If multiple objects are rejected as defective due to the same measurement location, specific conclusions can be drawn about possible errors in the production of the objects.

[0013] In particular, in the overview image, each measurement position of the object being measured is assigned an area of ​​the measurement table or the entire measurement table, and a pass / fail indication is output. Preferably, the confirmed measurement value is additionally output at that measurement position. For example, a so-called pass / fail indicator can be provided, which is easily understood by the operator. "Pass" is displayed for measurement positions within the tolerance range, and "Fail" is displayed for measurement values ​​at measurement positions outside the specified tolerance range.

[0014] After detecting or confirming a measurement task to be performed on at least one object to be measured, the calibration of the measuring device for the measurement task can be advantageously initiated and executed before the measurement task begins. This has the advantage of allowing calibration to be performed according to the selected measurement task, thereby achieving improved measurement quality.

[0015] Preferably, at the start of a measurement task, the measurement chamber of the housing is opened, and after at least one object to be measured is placed on the measurement table, the measurement task is started by a start signal, the measurement chamber of the housing is closed, the measurement task is performed, and after the measurement task is performed, the measurement chamber of the housing is opened to remove at least one object to be measured. In this way, measurements of objects stationary on the measurement table can be performed autonomously, so that the operator has time available while the measurement is being performed to, for example, monitor another measuring device or prepare for another measurement.

[0016] Furthermore, it is preferable that the measurement chamber of the housing be opened and closed by a housing cover that is controlled to be rotatable, slidable, or movable by a motor. This may increase the degree of automation when performing such measurements.

[0017] Furthermore, preferably, to facilitate the loading and unloading of objects to be placed on the measuring table, the measuring table is moved to a loading / unloading position that is at least partially guided from the closing measuring chamber of the housing. The movement of the measuring table in this loading / unloading position can be performed via a motor, which also controls the moving measuring table to move the measuring chamber of at least one object to be measured for at least one measuring position to be detected.

[0018] The method for performing the selected measurement task is preferably initiated by a button element on the housing, allowing for easy operation.

[0019] The object of the present invention is further achieved by an X-ray fluorescence apparatus for measuring an object to be measured using X-ray fluorescence, wherein the apparatus comprises a housing and a measuring table provided within the housing and movable relative to a measurement point of the X-ray fluorescence apparatus within the housing, the radiation source within the housing is aligned with the measurement point, and the housing is provided with a housing cover or housing opening for opening and closing a measuring chamber in which the measuring table can be placed, and the apparatus has a control device equipped with a data processing device for performing the method according to any of the above embodiments.

[0020] Such a measuring device simplifies the handling and execution of measurement tasks for at least one object to be measured. Furthermore, the degree of automation can be increased because the type of object to be measured, the position and / or arrangement of at least one object to be measured can be detected from the overview image of the optical device in order to continue initiating and executing the measurement task.

[0021] The present invention and other advantageous embodiments and their development will be described in more detail below with reference to the examples shown in the drawings. Features to be adopted from the specification and drawings can be used individually or in any combination according to the present invention. [Brief explanation of the drawing]

[0022] [Figure 1] A perspective view of the measuring device is shown. [Figure 2] Figure 1 shows a schematic cross-sectional view of the measuring device. [Figure 3] Figure 1 shows a schematic diagram of the measuring table of the measuring device equipped with the object to be measured. [Figure 4] A schematic partial diagram of a measuring table, comprising the object to be measured and its selected measurement position, is shown. [Figure 5] This diagram shows a schematic partial view of a measurement table that contains the object to be measured and the measurement results assigned to the measurement location. [Figure 6]Fig. 1 shows a schematic flow chart for performing measurements with the measuring device according to Fig. 1.

Embodiments for Carrying Out the Invention

[0023] Fig. 1 shows a perspective view of the measuring device 11. Fig. 2 shows a schematic side view of the measuring device according to Fig. 1 in a sectional view. This measuring device 11 is for measuring a measurement object by X-ray fluorescence. Measurement by X-ray fluorescence can be used to measure the layer thickness of the coating of the measurement object and / or to analyze the material of the measurement object.

[0024] The measuring device 11 includes a housing 12 having a lower housing part 14 and an upper housing part 15, and a housing cover 16. The housing cover 16 is attached so as to be rotatable about a rotation axis 17, for example, so as to be able to access a measurement chamber 18 provided in the housing 12. Alternatively, the housing cover 16 can also be made movable or displaceable with respect to the housing 12 by a further mechanism. Also, instead of the rotatable housing cover 16, a housing opening that enables access to the measurement chamber 18 can be provided.

[0025] The lower housing part 14 houses a measurement table 21 that is movable upward. This measurement table 21 is driven to move in the X direction and the Y direction by a motor 22. Preferably, the measurement table 21 is guided by a cross table or the like so as to be movable with respect to the lower housing part 14.

[0026] The upper housing 15 is equipped with an X-ray fluorescence apparatus 23. This includes a radiation source 24 from which primary radiation 25 is directed towards a measurement point 26. Individual components positioned within the primary radiation 25, such as a shutter, primary filter, and / or collimator, are not shown in more detail. For example, individual objects 27 stationary on a measurement table 21 can be placed at the measurement point 26 for measurement. Adjacent to the radiation source 24 is a detector 28, which detects secondary radiation 29 emitted by the objects 27. Both the radiation source 24 and the detector 28 are connected to a control device 31.

[0027] The X-ray fluorescence apparatus 23 can be positioned either above or below the measurement point 26 in order to direct the primary radiation to the measurement point 26 from above or below.

[0028] The control device 31 includes a data processing device 32 that can store and retrieve measurement tasks and / or record, store and / or evaluate and / or output confirmed measurement values ​​to a display or the like.

[0029] The upper housing 15 is provided with an optical device 33, such as a CCD camera, which can acquire an overview image of at least one area of ​​the measurement table 21, or preferably the entire measurement table 21. The optical device 33 can acquire images of the measurement point 26 and / or the measurement table 21, for example, via a deflection mirror 20. The housing cover 16 can be automatically opened and closed via a motor 34, which is then connected to a control device 31. This facilitates access to the measurement chamber 18. The lower housing 14 is preferably provided with a button element 36, which can be used to start, stop, and / or control the control device 31.

[0030] Advantageously, displays, screens, etc., can be connected to the measuring device 11. The housing 12 may also be equipped with indicators, displays, or screens.

[0031] To facilitate the placement of the measuring table 21 together with at least one object to be measured 27 for subsequent measurement tasks, the measuring table 21 can be moved to a loading / unloading position 35. In this loading / unloading position 35, the measuring table 21 protrudes at least partially from the lower housing 14. A housing cover 16 that can be lifted from the lower housing 14 can improve access to the measuring table 21 when it is positioned in the loading / unloading position 35. This loading / unloading position 35 of the measuring table is shown in Figure 1.

[0032] To perform the next measurement task, the measurement table 21 is moved from the loading / unloading position 35 to the working position 37. This working position 37 is shown in Figure 2, and the measurement table 21 is positioned entirely inside the measurement chamber 18. After closing the housing cover 16, the measurement table 21 is fully positioned inside the closed measurement chamber 18.

[0033] Alternatively, the loading / unloading position 35 and the working position 37 can be in the same location. In this case, the housing cover 16 is preferably liftable or laterally displaceable relative to the lower housing portion 14, thereby providing good access again for loading and unloading the measuring table 21 together with at least one object to be measured 27. The object to be measured 27 (there may be more) can be placed on the measuring table 21 manually or in an automated manner, for example, using a controllable and / or programmable handling device.

[0034] Figure 3 shows a schematic view of the measuring table 21 from above, on which several objects to be measured 27 are arranged. Preferably, some or all of the objects to be measured 27 from the manufacturing batch to be inspected can be placed on the measuring table 21. The position and / or arrangement here may be arbitrary. A so-called disorderly layout of the objects to be measured 27 on the measuring table 21 can be provided, where they are not placed on the measuring table 21 or facing each other.

[0035] Furthermore, identifiers 38 can be placed on the measurement table 21. Such identifiers 38 can also be placed on or within the object to be measured 27. Identifiers 38 can also be placed separately on the measurement table 21. These identifiers 38 can contain various information. For example, they can include a code in which a stored measurement task for a particular object to be measured 27 is recalled by the data processing device 32, or information such as the type of object to be measured and / or the measurement task, and / or tolerances used as the basis for the measurement task. Such identifiers 38 may be, for example, a QR code or a barcode or other identifier. Since such identifiers 38 are detected by the optical device 33, the detected data is passed to the control device 31 for subsequent measurement tasks.

[0036] Figure 4 shows a schematic diagram of one object to be measured 27 on the measurement table 21. The measurement table 21 can be moved in the X / Y measurement table coordinate system. Each object to be measured 27 has its own coordinate system having an X' axis and a Y' axis. To perform the measurement task in an automated manner, the X' / Y' object coordinate system is converted to the X / Y measurement table coordinate system, and as a result, the control device 31 can control the target traverse movement of the measurement table 21 to position at least one measurement position P1, P2, P3, P4, P5 of the object to be measured 27 at the measurement point 26, for example. The number of measurement positions for each object to be measured 27, as well as the position of at least one measurement position for each object to be measured 27, can be arbitrarily selected and determined for each object to be measured 27, depending on the measurement task and / or quality control.

[0037] Figure 5 shows a schematic diagram of the object being measured 27 after the measurement has been performed and the measured value has been evaluated, compared with the stored target value. The display can be output on an indicator, display, or screen.

[0038] In an exemplary case, the measured values ​​are presented by a so-called pass / fail indication. For example, the word "pass" (pass or good) is added to the measurement locations P1, P3, P4, and P5 of the object being measured 27. That is, these measurement locations are found to be good, or the detected measured values ​​at the measurement locations are within the tolerance range of a specific associated setpoint.

[0039] The measurement position P2 of the object being measured 27 is designated as "Fail" (unacceptable or not acceptable). That is, the measured value detected at measurement position P2 is outside the acceptable range of the associated set value. This allows the operator to easily identify which object being measured 27 on the measurement table 21 is good or defective. It also makes it easy to identify which measurement position of the object being measured 27 does not meet the requirements.

[0040] The presentation of measurement results for the object 27 shown in Figure 5 has the advantage of making it easy to draw conclusions about measurement locations that are outside the specified tolerance range. Alternatively, instead of presenting the measurement results for the measurement task performed, a display using a table of measurement points with associated numbers can also be output. For example, the measurement results may have a colored background, with measurement locations and / or measurements with a green background being presented as measurement points within the tolerance range, and measurement locations and / or measurements with a red background being labeled as outside the tolerance range.

[0041] The sequence program shown in Figure 6 illustrates a method for automatically measuring at least one object 27 using a measuring device 11 with fluorescent X-rays. Here, the measuring device 11 can be used for both measuring the thickness of a thin layer of the object 27, i.e., layer thickness analysis, and material analysis. The procedure described below is the same.

[0042] In step 51, the measuring device 11 is moved to the starting position for the subsequent measurement task. This starting position is shown in Figure 1, with the housing 12 open and the measuring table 21 extended at least partially relative to the housing 12 and positioned at the loading / unloading position 35. Proceeding from this starting position, one or more objects to be measured 27 are placed on the measuring table 21.

[0043] Next, in step 52, the button element 36 of the housing 12 is activated to perform automatic measurement.

[0044] In the next step 53, the measurement table 21 is moved to the working position 37 and the housing cover 16 is closed by the motor 34. After the measurement chamber 18 is completely closed off from the surrounding environment, the optical device 33 generates an overview image of the measurement table 21 with at least one object to be measured 27 stationary on it in step 54 and evaluates this overview image. For example, the evaluation of the overview image shown in Figure 3 can be performed by the data processing device 32, which can store characteristic data of the object to be measured 27, and can evaluate at least one object to be measured 27 stationary on the measurement table 21 by evaluating the detected image points.

[0045] If identifier 38 is placed in the measurement table 21, or if identifier 38 is applied to the object to be measured 27 itself, this identifier can be read, and at least the type of object to be measured 27 can be detected. Depending on the detected type of object to be measured 27, a measurement task is selected and called accordingly from the data processing device 32. The measurement task can also be determined from identifier 38.

[0046] In a further step 55, the position and / or arrangement or orientation of at least one object to be measured 27 is determined from the overview image shown in Figure 3 by an image processing algorithm.

[0047] Before a measurement task is performed to measure individual objects 27, a calibration routine for the measuring device 11 can be started. This calibration routine can move one or more calibration criteria, which may also be placed on the measurement table 21, relative to the measurement point 26 in order to calibrate the X-ray fluorescence apparatus 23 for subsequent measurement tasks.

[0048] In step 56, an X' / Y' object coordinate system is defined for the object 27 based on the data from step 55. Based on the definition of the X' / Y' object coordinate system, individual measurement positions, for example, measurement positions P1 to P5, can be defined. Subsequently, the X' / Y' object coordinate system is converted to the X / Y measurement table coordinate system. Then, the individual measurement positions P1 to P5 of the object 27 are approached by traversing the measurement table 21.

[0049] In the subsequent step 57, the measured values ​​at individual measurement positions P1 to P5 of the object to be measured 27 are detected and evaluated by the data processing device 32. The evaluation is performed based on predetermined set values ​​to which tolerances can be assigned. The tolerances or permissible values ​​at individual measurement positions P1 to P5 can be determined by the user and assigned individually and independently of each other. The user can determine this through a test plan before starting the measurement task. For example, a tolerance of, say, 10% can be assigned to measurement positions P1, P2 and P3, and a larger or smaller percentage tolerance can be assigned to measurement positions P4 and P5. This may also depend on the specific function of the measurement positions of the object to be measured 27.

[0050] In a further step 58, the measurement results are recorded in a log and output. For example, as shown in Figure 5, the measurement results can be output to a display or indicator, or the results can be output in a tabular format, with simultaneous evaluation of good and defective products, or evaluation of the measurement location. The good / bad output can also be specified using color marks.

[0051] In step 59, for example, the housing cover 16 is opened and the measuring table 21 is moved to the loading / unloading position 35. The objects to be measured 27 are removed from the measuring table 21 and sorted as good or bad products according to the evaluation. Subsequently, the measuring device 11 can perform new measurements.

Claims

1. A method for measuring a measurement object (27) on a measurement table (21) of a measurement device (11) using fluorescent X-rays, comprising: At least one measurement object (27) is placed on the measurement table (21); an overview image of at least one area of ​​the measurement table (21) on which the at least one measurement object (27) is placed is acquired by an optical device (33); the type of the measurement object (27) is determined from an overview image or from an identifier (38) provided on the at least one measurement object (27) or arranged adjacent to the measurement table (21); a position and / or arrangement of the at least one measurement object (27) on the measurement table (21) is determined from the overview image; a measurement task stored in the data processing device (32) is selected and started for the at least one detected measurement object (27); At least one measurement position (P1, P2, P3, P4, P5) of the at least one measurement object (27) is aligned with a measurement point (26) of the X-ray fluorescence device (23), and at least one measurement value is determined from the at least one measurement position (P1, P2, P3, P4, P5) of the measurement object (27); A method for comparing the at least one measurement value of the at least one measurement position (P1, P2, P3, P4, P5) of the measurement object (27) with a set value stored in the data processing device (32), and outputting a measurement result corresponding to the at least one measurement position (P1, P2, P3, P4, P5) of the measurement object (27).

2. 2. A method according to claim 1, characterized in that an overview image of the entire measuring table (21) is acquired by the optical device (33).

3. 2. The method according to claim 1, characterized in that, when the identifier (38) placed on the measuring table (21) or on the measuring object (27) is recognized, the identifier (38) is read out, and the measurement task stored in the identifier (38) is read out from the data processing device (32) and initiated and executed by a control device (31).

4. 2. The method according to claim 1, characterized in that, before the start of the measurement, a tolerance range for the at least one measurement position (P1, P2, P3, P4, P5) is assigned to the at least one measurement position (P1, P2, P3, P4, P5) of the measurement object (27) for each measurement task.

5. 2. The method of claim 1, wherein the position and / or location of the measurement object (27) is determined in an X' / Y' measurement object coordinate system, and the X' / Y' measurement object coordinate system is transformed into an X / Y measurement table coordinate system.

6. 6. The method according to claim 5, characterized in that after transforming the X' / Y' measurement object coordinate system into the X / Y measurement table coordinate system, the at least one measurement position (P1, P2, P3, P4, P5) of the at least one measurement object (27) is controlled by a control device (31) through a traverse movement of the measurement table (21) in the X and / or Y direction, and is successively aligned with the measurement point (26).

7. 7. The method according to claim 6, characterized in that the measurement result determined by the at least one measurement position (P1, P2, P3, P4, P5) of the measurement object (27) is output together with a pass / fail indication assigned to the measurement position (P1, P2, P3, P4, P5).

8. 8. The method according to claim 7, characterized in that in the overview image determined by the optical device (33), which includes at least one area of ​​the measurement table (21) together with the at least one measurement object (27), the pass / fail indication is assigned to the at least one measurement point (P1, P2, P3, P4, P5) of the measurement object (27) and output.

9. 9. The method according to claim 8, characterized in that the determined measured values ​​are additionally displayed at the associated measuring positions (P1, P2, P3, P4, P5) of the measuring object (27).

10. 2. The method according to claim 1, characterized in that after detection or determination of the measurement task to be performed, a correction of the measuring device (11) as a function of the measurement task to be performed is initiated and performed before the measurement task is started.

11. 2. The method according to claim 1, characterized in that the measuring chamber (18) of the housing (12) is opened at the start of the measurement task to be performed, the at least one measurement object (27) is placed on the measurement table (21), the measurement task is started by a start signal, the measuring chamber (18) of the housing (12) is closed, the measurement is performed according to the measurement task, and after the measurement task has been performed, the measuring chamber (18) of the housing (12) is opened and the at least one measurement object (27) is removed.

12. 12. The method according to claim 11, characterized in that the measuring chamber (18) of the housing (12) is opened and closed by a housing cover (16) that is controlled to be rotatable, slidable or movable by a motor (34).

13. 12. The method according to claim 11, characterized in that for loading and unloading the at least one measurement object (27), the measuring table (21) is moved to a loading and unloading position (35) in which the measuring table (21) is at least partially guided out of the closable measuring chamber (18) of the housing (12), and for performing the measurement task, the measuring table (21) is moved to a working position (37) located inside the measuring chamber (18).

14. 2. The method of claim 1, wherein the measurement task to be performed is initiated by a button element (36) on the housing (12).

15. A measuring device for measuring a measurement object (27) using fluorescent X-rays, a housing (12); a measurement table (21) provided in the housing (12) and movable relative to a measurement point (26) of the housing (12); an X-ray fluorescence device (23) including a radiation source (24) and a detector (28) aligned with the measurement point (26); a housing cover (16) or a housing opening for opening and closing a measurement chamber (18) of the housing (12), the measurement table (21) being accessible when the housing (12) is open for loading and unloading the measurement table (21) together with at least one measurement object (27); 2. A measuring device, characterized in that it is provided with a control device (31) for carrying out the method according to claim 1.

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