Calibration device for a measuring instrument and method for calibrating a measuring instrument

Abstract

The present invention relates to a calibration device for a measuring instrument and a method for calibrating a measuring instrument intended to analyze materials or layer thicknesses using a calibration device (11) consisting of a housing (12) with a carrier (18) having a plurality of sections (28, 29, 30), having a drive (16) which can be used to alternately transport the sections (28, 29, 30) of the carrier (18) into a measurement position (49), having a controller (17) which controls the drive (16) to move the carrier (18), and providing at least one calibration standard (34) in at least one section (28) having a data interface (26) connected to the controller (17) and provided for communicating with the measuring instrument (42).

Description

[Technical Field]

[0001] The present invention relates to a calibration device for a measurement instrument and a method for calibrating a measurement instrument using such a calibration device for material or coating thickness analysis. [Background technology]

[0002] German Patent Application No. 102005054589 (B4) describes a known calibration device for non-destructively calibrating a measuring instrument for non-destructively measuring the thickness of thin layers. The calibration device comprises a carrier plate made of a substrate and several calibration standards applied to the carrier plate. Each calibration standard has a different layer thickness, for which the measuring instrument is to be calibrated. To perform the calibration, the measuring instrument is placed on the carrier plate with the base, and the measuring probe of the measuring instrument is placed successively on selected calibration standards. This calibration can increase the measurement accuracy of the measuring instrument. After the measuring instrument is calibrated, individual measurements are performed on the measurement object according to the measurement task.

[0003] Furthermore, measuring instruments are known that enable material analysis using X-ray fluorescence, for example to determine different proportions of elements in a material or coating. Furthermore, measuring instruments enable coating thickness analysis using X-ray fluorescence. For such measuring instruments for material or coating thickness analysis, it is necessary to calibrate these measuring instruments with the X-ray fluorescence instrument. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] German Patent Application Publication No. 102005054589(B4) Summary of the Invention [Problem to be solved by the invention]

[0005] Calibrating such measuring instruments requires more time for calibration due to performing several measurements on different calibration standards, followed by reconfiguration time that occupies the personnel operating such measuring instruments for measuring a given batch of measurement objects. In addition, calibration by manually placing calibration standards on the measuring instrument may entail the risk that the calibration will not be performed at the isocenter of the measuring instrument, which may result in calibration errors that lead to a decrease in measurement quality. [Means for solving the problem]

[0006] The present invention is based on the problem of proposing a calibration device for measuring instruments for material analysis or coating thickness analysis, which allows for improved calibration to increase the measurement accuracy of the calibrated instrument. Furthermore, the present invention is based on the problem of proposing a method for calibrating measuring instruments for material or coating thickness analysis, which allows for increased calibration accuracy and thus improved measurement accuracy of the measuring instrument for subsequent measurement operations.

[0007] The problem behind the present invention is solved by a calibration device for measuring instruments for material analysis or coating thickness analysis, in particular for X-ray fluorescence measuring instruments, the calibration device comprising: a carrier having a plurality of sections, at least one calibration standard being provided in at least one section; a drive device capable of moving the sections of the carrier into measurement positions alternately or sequentially; a controller provided in the housing, which controls the drive device to position the carrier in the measurement position and is capable of moving the sections of the carrier into the measurement positions alternately or sequentially; a controller provided in the housing, which controls the drive device to position the carrier in the measurement position; and a data interface through which the controller of the calibration device communicates with a data interface of a control device of the measuring instrument to be calibrated.

[0008] The calibration device is preferably designed separately from the measuring instrument and / or as an independent component of the measuring instrument. Such a calibration device allows at least one portion of the carrier containing or carrying the calibration standards to be transferred to a measurement position on or in the measuring instrument for subsequent measurements of the measuring instrument to be calibrated, where the X-ray radiation of the measuring instrument is directed onto the calibration standards to detect calibration values. Through communication between the measuring instrument and the calibration device via a corresponding data interface, the carrier can be transferred sequentially or alternately to corresponding measurement positions associated with the carrier portions via control of the calibration device, so that, for example, a corresponding number of calibration standards and / or selected calibration standards selected by the control device of the measuring instrument based on subsequent measurement operations can be transferred to the measurement positions to perform calibration of the measuring instrument. This allows the calibration standards arranged at least in the carrier portions to be transferred to the measurement positions with repeatability, so that measurements for calibration on the measuring instrument are ensured to be aligned with the centers or isocenters of the calibration standards. This allows for improved calibration and therefore more precise measurement accuracy for the measuring instrument to be calibrated. Once the measurement instrument has been calibrated, the calibration device can be used for the next measurement instrument to be calibrated.

[0009] Preferably, the carrier has several consecutively arranged sections that can be transferred one after the other to the measurement position, which allows for easy control of the calibration device and saves time when performing calibrations using the measurement equipment.

[0010] Advantageously, it can be provided that each site on the carrier has an identification code that can be read by an optical camera of the calibration device or measuring instrument, and that the control system can transfer the corresponding identified site to the measurement location. This preferably individualized identification code can be, for example, not only a one-dimensional code such as a QR code or a barcode, but also any combination of numbers and / or figures. By detecting the identification code with the optical camera, the corresponding calibration standard assigned to the site can then be selected and transferred to the measurement location to calibrate the measuring instrument. This can increase the reliability of the process for calibrating the measuring instrument.

[0011] Alternatively, the drive for controlling the transverse movement of the carrier of the calibration device can have a position sensor, and one of the portions can be aligned with the position sensor at a start or initial position, and the position sensor can detect the angle or increment of rotation to control the other portion in a defined manner and transfer it to the corresponding measurement position. This allows selective control, making it possible to align individual portions of the carrier to the measurement position. Moreover, the carrier can instead be provided with an indexing feed, and the controller in the housing can query the indexing feed and then use the movement of the carrier to detect the zero or start position from the indexing feed to transfer the corresponding portion to the measurement position, so that the corresponding positions of the portions relative to each other are known.

[0012] According to a preferred embodiment of the calibration device, the carrier is designed as a rotating disk having several sections distributed around its circumference, these sections preferably having the shape of a slice of cake.

[0013] Advantageously, the sites arranged around the periphery are evenly distributed on the carrier. For example, 2, 4, 6, 8, or 12 sites can be provided on the carrier, or 12 sites can be provided to accommodate a minimum number of calibration standards. For example, calibration standards made from pure elemental gold, silver, platinum, lead, and / or chromium can be provided for material analysis of precious metals, such as to determine the components or elements in pure gold.

[0014] According to another preferred embodiment of the carrier, it is provided that each section has a container for positioning a calibration standard. Such calibration standards are preferably produced in an accredited testing laboratory and provided as a coated substrate or consist of a foil. The carrier can be equipped with such calibration standards for the corresponding calibration operation. Preferably, a holder for aligning the calibration standards is provided in order to correctly position the calibration standards in the sections. Alternatively, a support surface on which the calibration standards can be positioned can be provided in the carrier section.

[0015] Furthermore, it may be provided that the carrier has a predetermined number of sites or that all sites have a fixed configuration with different calibration standards, which means that a pre-assembled carrier or a pre-assembled calibration device can be designed for a measurement task specific to the measurement instrument.

[0016] Moreover, the carriers are preferably interchangeable along with the drive units within the housing, allowing for quick and easy conversion of the calibration device for different calibration tasks. Advantageously, storage space can be provided within the housing for storing individual carriers.

[0017] According to another preferred embodiment of the calibration device, the carrier has a pinhole opening in at least one region, which allows, for example, a measurement object to be aligned with the pinhole and measured by the measuring device, and then the carrier plate can be transported to another measurement position where the region of the carrier arranged at the measurement position is positioned together with a calibration or verification standard not used for calibration, so that a comparison can be made between the measurement value of the measurement object and the measurement value of the calibration and / or verification standard to determine whether the measurement performed on the measurement object is within defined limits or below a predetermined threshold.

[0018] Furthermore, it may be preferable for the carrier to have a perforated plate covered with a membrane in at least one of the regions. In particular, the membrane is designed as a Mylar membrane. This allows small objects to be placed in the regions with a surface area smaller than the aperture. Such a Mylar membrane is invisible to X-rays, i.e., it does not contain any components that interfere with the primary and secondary radiation emitted by the object to be measured in the X-ray fluorescence range.

[0019] The carrier of the calibration device is preferably made from a material that is low in reflectivity, in particular non-reflective, and / or low in absorption, in particular non-absorbing, with respect to X-rays, in particular a plastic material without additives. For example, the carrier can be made from a thermoplastic material, in particular polyethylene, polycarbonate, or polymethyl methacrylate.

[0020] The data interface provided on the housing of the calibration device is preferably designed for wireless communication with the measuring device to be calibrated. Conventional standards such as Wi-Fi or Bluetooth can be used. Alternatively, the data interface on the housing of the calibration device can also be designed for wired communication with the measuring device. This can be, for example, a known USB interface or a variant thereof.

[0021] Moreover, the carrier in the housing is preferably accommodated by an axis rotatable about an X / Y plane parallel to the measurement surface of the measurement device, so that the individual features can be gradually transported to measurement points in the measurement surface of the measurement device where they are exposed to X-rays by the X-ray fluorescence device.

[0022] Furthermore, the carrier preferably has an arcuate segment-shaped portion protruding from the end face opposite the housing. This protruding arcuate segment-shaped portion can be aligned with a measurement point in the measurement surface of the measurement device. Calibration standards, identification codes, pinhole openings, and / or foil-covered pinhole openings are provided in corresponding portions of the arcuate segment-shaped portion protruding from the housing. Alternatively, it may be provided that the carrier is fully rotatable in the X / Y plane inside the housing and is aligned parallel to the measurement surface of the measurement device. Advantageously, the housing has a housing opening on a wall portion facing the measurement surface of the measurement device.

[0023] Furthermore, it is preferred that the housing of the calibration device has a support surface or support point, and that the plane of the support surface or support point and the measurement point or measurement surface of the calibration standard or measurement object on or in the carrier are separated by less than 10 mm, preferably less than 5 mm, preferably less than 3 mm. In particular, for calibration standards with thin layers used for calibration, a short distance is advantageous to achieve maximum intensity of the secondary radiation.

[0024] According to another preferred design of the calibration device, the calibration standard is designed as a pure element or as a layered element consisting of a substrate and a coating. In the case of a precious metal such as gold, pure element is understood to mean a purity of gold greater than 99%. The same applies to other precious metals.

[0025] The problem behind the present invention is further solved by a method for calibrating a measuring instrument for analyzing the thickness of materials or coatings, in particular an X-ray fluorescence measuring instrument, comprising: calling up and selecting a measurement operation to be subsequently performed in a control instrument of the measuring instrument; transporting a calibration device to a calibration position for the measuring instrument according to one of the embodiments described above; moving individual calibration standards arranged in positions on a carrier to measurement positions where the selected carrier positions are aligned with measurement points on the measurement surface of the measuring instrument; transferring measurement data obtained from the calibration standards arranged in the corresponding positions on the carrier to the control instrument; determining calibration values ​​from the measurement data of each calibration standard; comparing the standard values ​​stored in the control instrument with the recorded calibration values; and determining correction values ​​for subsequent measurement operations using the measuring instrument to use as references. This method has the advantage that the calibration device calibrates the measuring instrument for the subsequent measurement operation, allowing the operating personnel to devote their attention to other activities while the measuring instrument is being calibrated. This method also eliminates operator errors, for example, when the calibration standards are mixed up or when the calibration standards are not aligned with the isocenter of the measurement point in the measurement surface of the measurement instrument.

[0026] Preferably, there is provided for aligning at least one portion of the carrier of the calibration device with a measurement location of the measurement device to assume the calibration position. Preferably, the calibration device can then be positioned over the measurement surface of the measurement device to make an adjustment to align the at least one portion of the carrier with a measurement location in the measurement surface of the measurement device.

[0027] In particular, alignment of the measurement standard in the carrier portion with the measurement point in the measurement surface of the measurement instrument is indicated by a positioning laser on the measurement instrument, or by a measurement imaging camera capturing the measurement point, as indicated on the display of the measurement instrument, making it easy to ensure that the calibration position has been reached.

[0028] Furthermore, it is preferable to establish communication between the calibration device and the measurement device at the calibration position via a data interface of the calibration device and a control device in the measurement device. For example, particularly in the case of wireless communication, the calibration device may have to be actively coupled to the measurement device when the measurement device is first positioned. During subsequent or other calibrations, secure wireless communication can be established independently between the calibration device and the measurement device. Alternatively, the communication may be wired.

[0029] A further preferred embodiment of the method provides the number and / or corresponding calibration standards to be used for calibration selected by the control device of the measurement device based on the selected measurement task, thereby preventing confusion of calibration standards or incorrect calibration due to a reduced number of calibration standards.

[0030] According to a preferred embodiment of the method, a carrier equipped with calibration standards is selected for subsequent measurement operations of the measuring instrument. The carrier can be permanently provided in a pre-assembled calibration device. The calibration device can also be equipped with selected carriers equipped with an assortment of calibration standards, or selected carrier sites can be equipped with predetermined calibration standards. In the case of serial production, for quality control purposes, it may be provided to use, for example, several pre-assembled calibration devices in order to save time in preparing the calibration device for a calibration operation. Alternatively, if a large number of different measurement operations are to be performed individually, it is also possible to select a calibration device with carriers that individually supply calibration standards to the individual sites.

[0031] Moreover, it is preferred that at least a predetermined number of sites are recorded together with the corresponding calibration standards of the calibration device and stored in the control unit of the measuring instrument.

[0032] Furthermore, it is preferred that the calibration of the measuring device be controlled by a control device for the measuring device, which sequentially transports the selected calibration standards to the measurement location for the measurement task, thereby enabling reliable and traceable calibration.

[0033] In particular, after performing calibration of the measurement device using at least one calibration standard of the calibration device, a verification standard that was not used for calibrating the measurement device is transferred to the measurement position and the calibration value is compared with the verification value of the verification standard. This allows additional adjustments to be made to the performed calibration. In particular, it is possible to monitor whether there were any external influences during the calibration of the measurement device, such as temperature fluctuations, that may have resulted in distorting the calibration of the measurement device.

[0034] Furthermore, after recording the verification value, it is preferable to measure the measurement object by placing the measurement object on the pinhole or the pinhole of the membrane-covered carrier, then record the reference value, and then determine the difference between the verification value and the reference value. If the reference value is less than a specified threshold, the calibration can be completed and the measurement device can then be activated for measurement operation. If the reference value is greater than a specified threshold, a request to repeat the calibration can be made.

[0035] According to another advantageous embodiment of the method, the calibration device may comprise a measurement support positioned behind the support with the primary beam directed towards the support, and after one or more measurements of the measurement object on the measurement support, the support with the pinhole and at least a predetermined number of sites with the calibration standards is moved to the measurement position for calibration. This arrangement makes it possible to perform calibration automatically after each measurement or after a predetermined number of measurements during testing of a batch of measurement objects, for example, in order to initiate a recalibration in case of possible deviations in the measuring device.

[0036] Furthermore, it may be preferable to provide for the use of an automatic changer for the measurement objects instead of the carriers arranged in the calibration device, which is designed in the same way as the carriers, but on which a predetermined number of measurement objects can be placed so that the measuring instrument can automatically trigger successive measurements of the measurement objects via the calibration device.

[0037] The invention, as well as other advantageous and alternative embodiments of the invention, will be described and explained in more detail below with reference to examples shown in the drawings, in which the features taken from this description and the drawings can be used according to the invention individually or in any combination. [Brief explanation of the drawings]

[0038] [Figure 1] FIG. 2 is a schematic side view of a calibration device. [Figure 2] 2 is a schematic view from above of the calibration device according to FIG. 1; [Figure 3] 2 is a schematic view from above of the carrier of the calibration device according to FIG. 1; [Figure 4] 4 is a schematic cross-sectional view of a portion of the carrier as shown in FIG. 3. [Figure 5] 4 is a schematic cross-sectional view of the carrier of FIG. 3 taken along line VV. [Figure 6] 1 is a schematic side view of a calibration device in a calibration position relative to a measurement instrument; [Figure 7] FIG. 7 is a schematic side view of an alternative embodiment to FIG. 6. [Figure 8] FIG. 7 is a schematic side view of another alternative embodiment to FIG. 6. DETAILED DESCRIPTION OF THE INVENTION

[0039] FIG. 1 shows a schematic side view of a calibration device 11. A top view of the calibration device 11 is shown in FIG. 2. The calibration device 11 comprises a housing 12. A support surface or support point 14, lying within a support plane 24, is provided on the underside of the housing 12 for positioning on a surface. The housing 12 comprises a drive 16, specifically an electric motor, rotatably driven by a control unit 17. The drive 16 controls the movement of a carrier 18 relative to the housing 12. The carrier 18 has a base 19, e.g., in the form of a rotating disk. An axis of rotation 20 of the support 18 is preferably aligned perpendicular to the support plane 24 of the support point 14. The carrier 18 is arranged in a position relative to the housing 12 such that an arcuate segment-shaped portion 21 of the carrier 18 protrudes from an end face 22, or front face, of the housing 12. The remainder of the carrier 18 is positioned within an open container 23 within the housing 12. Preferably, the distance A between the support 18 or the underside of the support 18 and the support point 14 or the support plane 24 formed by the support surface of the housing 12 is less than 10 mm, preferably less than 5 mm, in particular less than 3 mm.

[0040] In or on the housing 12 of the calibration device 11 is provided a data interface 26 connected to the control unit 17. The data interface 26 may have a mechanically designed plug connection for wired communication and / or for power supply. The data interface 26 can also be designed as a wireless communication interface. In this case, the calibration device 11 may have a separate power supply to the mains or can operate on a rechargeable battery.

[0041] FIG. 3 shows a plan view of the carrier 18 of the calibration device 11 according to FIGS. 1 and 2. The carrier 18 has a plurality of sections 28, which are preferably evenly distributed around the circumference. In this case, the sections 28 may have the same size. For example, the sections 28 may be in the shape of a pie slice. The sections 28 of the carrier 18 may be equipped with a calibration standard 34. The calibration standard 34 may be permanently integrated into the carrier 18. Alternatively, a container 35 may be provided in the section 28 for positioning the calibration standard 34. The container 35 may take the form of a recess, as shown in FIG. 4, which shows a cross-section along line IV-IV in FIG. 3. The calibration standard 34 may be inserted into the container 34. Furthermore, the carrier 18 may also be designed to hold a measurement object. In this case, for example, the carrier 18 may be a section 29 with a perforated opening 31 covered by a membrane, in particular a Mylar membrane 32, as shown in FIG. 4. In this way, a measurement object having a diameter smaller than the perforated opening 31 can be placed on the upper side of the carrier 18 or foil 32. Furthermore, as shown in FIG. 5 in the cross section along line VV according to FIG. 3, a region 30 can be formed in the carrier 18. This region 30 can consist solely of the perforated opening 31. The perforated opening 31 represents a free-flowing through-hole. The cross section along line VV according to FIG. 3 shows an alternative embodiment of the carrier 18 and the arrangement of the calibration standard 34 relative to the carrier 18. In this arrangement, the calibration standard 34 is rigidly arranged in the base 19 of the carrier 18 or is integral with the base 19 of the carrier 18.

[0042] The carrier 18 is mounted for rotation about a vertical axis 20. The carriers 18 may be interchangeably arranged within the housing 12 and provided for connection to the drive unit 16. For example, the carrier 18 may have an indexer so that it can be connected to the drive shaft of the drive unit 16 in a defined alignment. The drive unit 16 itself may be equipped with a position encoder so that the position and orientation of the indexer of the drive shaft are known to the control unit 17. Consequently, the control unit 17 of the calibration device 11 can be used to control the defined positioning of the individual segments 28, 29, 30 at a measurement position 49 (FIGS. 2 and 6). At this measurement position 49, a sufficient area of ​​each segment 28, 29, 30 of the carrier 18 protrudes from the end face 22 of the housing 12.

[0043] The substrate 19 of the carrier 18 is preferably made of a thermoplastic material without additives that lead to the absorption and / or reflection of X-rays, with polyethylene, polycarbonate or polymethyl methacrylate being preferred.

[0044] The calibration standard 34 can be designed as a so-called pure element for calibrating a measuring instrument 42 for material analysis, in particular an X-ray fluorescence measuring instrument as shown in FIG. 6. Such a pure element can consist of a precious metal with very high purity. The calibration standard 34 can also be designed as a substrate with a coating for calibrating a measuring instrument 42 for coating thickness analysis. The calibration standard 34 can be provided with an identification code such as a QR code or a barcode.

[0045] 6 shows a schematic side view of the measuring device 42. The measuring device 42 is an X-ray fluorescence measuring device. The measuring device 42 comprises an X-ray fluorescence device 43, which comprises a radiation source 44 for generating X-rays and at least one detector 46. The radiation source 44 emits primary radiation 45 directed onto a measuring point 47 in a measuring surface 48 of the measuring device 42. Secondary radiation 52 emitted by a measuring object 51 or a calibration standard 34 on a carrier 18 resting on the measuring point 47 is detected by the detector 46 to determine measured values. These measured values ​​are transferred to a control device 54 of the measuring device 42. The control device 54 is connected to a data interface 55.

[0046] Moreover, an optical device 56 is shown diagrammatically within the measuring device 42. This optical device 56, in particular a camera, captures an image of the measuring point 47 via a mirror, not shown in detail, coupled into the beam path in order to obtain the image of the measuring point 47.

[0047] The calibration device 11 is separate from the measurement device 42, specifically the measurement device 42 for coating thickness analysis. The calibration device 11 can be used to calibrate several measurement devices 42 consecutively. The calibration device 11 is designed to be detachable from the measurement device 42. The calibration device 11 is an independent unit. To calibrate the measurement device 42, the calibration device 11 is moved to a calibration position 58 on or in the measurement device 42. At this calibration position 58, the calibration device 11 is preferably positioned above the measurement surface 48 of the measurement device 42. The arcuate segment-shaped portion 21 of the carrier 18 protrudes from the housing 12 of the calibration device 11 and is aligned with the measurement point 47 of the measurement device 42, so that the primary radiation generated by the radiation source 44 impinges on the portions 28, 29, and 30 of the carrier 18 that are aligned with the measurement point 47.

[0048] A positioning laser provided on or in the measuring instrument 42 or the optical instrument 56 may be provided to align the calibration device 11 with the measurement point 47 in the measuring instrument 42. In the case of the optical instrument 56, the position of the portion 28 of the carrier 18 relative to the measurement point 47 is output, for example, to a display 57 of the measuring instrument 42. An acoustic signal may also be emitted.

[0049] Furthermore, at the calibration position 58, wireless or wired communication is established between the control unit 17 of the calibration device 11 and the control unit 54 of the measuring instrument 42.

[0050] Calibration of the measuring device 42 by the calibration device 11 can be carried out as follows: Furthermore, on a control panel 59 of the measuring device 42, which may take the form of a portable communication device, in particular a tablet, and which may be designed separately from the measuring device 42, the subsequent measurement task of the measuring device 42 is selected using operating software in the control device 54. For this purpose, the control device 54 outputs a corresponding number and / or type of calibration standards 34.

[0051] The calibration device 11 can be provided with a pre-assembled carrier 18 containing the calibration standards 34 required for the calibration operation. Alternatively, the carrier 18 can also be equipped with the corresponding calibration standards 34. Alternatively, the carrier 18 can also be replaced with another carrier for the housing 12 of the calibration device 11, which also comprises calibration standards for subsequent measurement operations.

[0052] The control unit 17 of the calibration device 11 then transmits information about the sites 28, 29, 30 of the carrier 18 that are aligned with the measurement points 47 in the measurement positions 49 to the control unit 54 of the measuring device 42. The calibration process is then initiated by the control unit 54 of the measuring device 42, which selects the individual sites 28, 29, 30 to perform corresponding measurements for calibration, for example by controlling several sites 28 with different calibration standards 34. From the position detection of the sites 28, 29, 30 relative to the measurement positions 49, the calibration standards 34 can be assigned to the measurements in order to determine the calibration values.

[0053] Provided that the carrier 18 is aligned with the drive 16 in the calibration device 11, the corresponding sites 28, 29, 30 at the measurement position 49 can be recognized by the control unit 17. Similarly, for recognition, the identification code of the calibration standard 34 or in the sites 28, 29, 30 can be queried by the measurement device 42 or the calibration device 11.

[0054] After measuring a predetermined number of calibration standards 34 for a selected measurement task and recording the calibration values ​​for each calibration standard 34, these calibration values ​​are compared with the standard values ​​stored in the control device 57 to determine correction values ​​to be taken into account during subsequent measurements of the measurement object. For subsequent measurement tasks to be performed with the measurement device 42, the calibration device 11 can be moved from the calibration position 58. Measurement objects can then be placed one after the other on the measurement position 47 and individual measurements can be taken and saved.

[0055] Alternatively, the carrier 18 can also be replaced by an automatic exchange device for holding the measurement object in the calibration device 11. The clocking or positioning of the measurement object can then be further controlled on the automatic exchange device by the control 17 unit of the calibration device 11 or by the control device 54.

[0056] Calibration of the measuring device 42 by the calibration device 11 may also include other steps. After recording the calibration values ​​obtained from a predetermined number of calibration standards 34 in the corresponding locations 28 of the carrier 18, the carrier 18 with, for example, location 29 or location 30 can be transported to the measurement position 49. A measurement is then performed by placing a reference object on the pinhole 31 or on the foil 32 covering the pinhole 31. This reference object or reference standard has not previously been used to calibrate the measuring device 42. However, this reference object is standardized in the same way as the calibration standards 34. The determined reference value can then be compared with the calibration value. If there is a difference value greater than a predefined threshold, a new calibration should be performed. If this difference value is smaller than the threshold, the calibration can be considered to have been performed correctly.

[0057] FIG. 7 shows an alternative embodiment of the calibration device 11 in a calibration position 58 relative to the measuring device 42. This calibration device 11 provides a measurement support 62 adjacent to the carrier 18. This measurement support 62 can be removably fastened to the end face 22 of the housing 12. The measurement support 62 preferably has a perforated opening 31, in particular covered with a foil 32, in which the measurement object 51 can be positioned. The foil 32 is preferably a Mylar film. After calibrating the measuring device 42 using the calibration device 11, the calibration device 11 remains in the calibration position 58 relative to the measuring device 42. The carrier 18 is aligned with the site 30 relative to the measurement position 47. The primary radiation of the X-ray fluorescence measuring device 43 directly impinges on the underside of the foil 32 of the measurement support 62, on which the measurement object 51 rests. The resulting measurement values ​​can be directly recorded by the detector 46. Next, if calibration is to be performed during a measurement or measurements of a single measurement object 51, the calibration device 11 can be controlled to position each site 28 at the measurement point 47 to obtain a calibration value. This arrangement makes it possible to perform, for example, a calibration, a measurement and a calibration. Furthermore, it is possible to provide for performing a calibration, a predetermined number of measurements and another calibration.

[0058] FIG. 8 shows another schematic cross-sectional view of an alternative embodiment of the measuring device 42 and the calibration device 11. In this embodiment, the calibration device 11 is integrated into the measuring device 42. The carrier 18 of the calibration device 11 is positioned below the measurement surface 48, i.e., between the measurement point 47 and the X-ray fluorescence device 43. All of the above-described embodiments and alternatives are also possible in this alternative embodiment. This arrangement has the particular advantage that, when using very thin foils for the calibration standards 34, it leads to a short distance to the X-ray fluorescence device 43, thereby maximizing the signal acquisition intensity for measurement value evaluation. The measurement surface 48 may be at least partially hinged or detachable, for example, to allow easy access to the calibration device 11 integrated into the measuring device 42, for mounting and / or replacing the carrier 18.

Claims

1. 1. A calibration device for a measuring instrument (42) for material analysis or coating thickness analysis, comprising: a housing (12) comprising: - having a carrier (18) with a plurality of sites (28, 29, 30), providing at least one calibration standard (34) in at least one of said sites (28); A housing (12); a drive (16) enabling said parts (28, 29, 30) of said carrier (18) to move alternately or successively into a measuring position (49); a control unit (17) for controlling said drive (16) to move said carrier (18); a data interface (26) connected to said controller (17) and communicating with a data interface (55) of said measuring device (42) to be calibrated; A calibration device comprising:

2. 2. Calibration device according to claim 1, characterized in that the carrier (18) comprises several of the portions (28, 29, 30) arranged consecutively and which can be transferred to the measurement position (49).

3. 3. The calibration device according to claim 1, wherein at least one of the portions (28, 29, 30) of the carrier (18) has an identification code that can be read by an optical device on the housing (12) or on the measuring device (42), and the corresponding identified portion (28, 29, 30) can be transported to the measuring position (49) by the controller (17).

4. 4. The calibration device according to claim 1, wherein the drive device (16) has a position transmitter, one of the parts (28, 29, 30) is aligned with the position transmitter at a start position, and each of the parts (28, 29, 30) can be transported to the measurement position (49) in a defined manner by the position transmitter detecting a rotation angle or increment.

5. 5. Calibration device according to any one of claims 1 to 4, characterized in that the carrier (18) has a base (19) designed as a rotating disk with the plurality of sites (28, 29, 30) distributed over its periphery, preferably the plurality of sites (28, 29, 30) being provided uniformly distributed over the periphery.

6. 6. Calibration device according to claim 1, characterized in that the carrier (18) has in at least one of the portions (28) a container (35) for positioning the calibration standard (34) or a support surface for a measurement object.

7. Calibration device according to any one of the preceding claims, characterized in that said carrier (18) has a permanent assembly of said calibration standards (34) in said portion (28).

8. Calibration device according to any one of the preceding claims, characterized in that the carrier (18) is provided so as to be exchangeable together with the drive device (16) in the housing (12).

9. 9. Calibration device according to any one of claims 1 to 8, characterized in that the carrier (18) has a pinhole (31) in the region (29), preferably a pinhole (31) in the region (29) covered with a membrane (32), in particular a pinhole (31) covered with a Mylar membrane.

10. 10. Calibration device according to any one of claims 1 to 9, characterized in that the base (19) of the carrier (18) is made from a material that is low-reflecting, in particular non-reflective, and / or low-absorbing, in particular non-absorbing, with respect to X-rays, the base (19) being made in particular from polyethylene, polycarbonate or polymethyl methacrylate.

11. Calibration device according to any one of claims 1 to 10, characterized in that the data interface (26) in the housing (12) is designed for wired or wireless communication with the measuring device (42).

12. 12. The calibration device according to claim 1, wherein the carrier (18) is rotatably mounted in the housing (12) by a vertical axis and accommodated in an X / Y plane parallel to a measurement surface (48) of the measuring instrument (42).

13. 13. A calibration device according to claim 1, characterized in that the carrier (18) has an arcuate segment-shaped portion (21) protruding from the opposite end face (22) of the housing (12), or the carrier (18) is provided entirely inside the housing (12), the portions (28, 29, 30) of the carrier (18) being accessible from the outside through a housing opening in the housing (12).

14. 14. The calibration device according to claim 1, wherein the housing (12) has a support surface or support point (14) forming a support plane (24), and the measurement points or measurement surfaces of the calibration standard (34) or the measurement points or measurement surfaces of the measurement object (51) on or in the support (18) are at a distance of less than 10 mm, preferably less than 5 mm, particularly preferably less than 3 mm from the support plane (24).

15. Calibration device according to any one of claims 1 to 14, characterized in that the at least one calibration standard (34) is designed as a pure element or as a layered element consisting of a substrate and a coating.

16. 1. A method for calibrating a measuring instrument (42) for material analysis or coating thickness analysis, comprising: - selecting the measurement task to be subsequently performed by the control device (54) of said measuring device (42), - arranging a calibration device (11) according to any one of claims 1 to 15 in a calibration position (58) relative to the measuring device (42) to be calibrated, - the data interface (26) of said calibration device (11) communicates with the data interface (55) of said measuring device (42) in order to calibrate said measuring device (42); moving each calibration standard (34) arranged in a portion (28, 29, 30) of the carrier (18) selected for subsequent measurement output by the control device (54) to a measurement position (49) relative to the measurement device (42) within the calibration device (11) and performing a calibration measurement; - transferring measurement data determined from the calibration standards (34) arranged in the corresponding portions of the carrier (18) to the control device (54) and determining a calibration value from each of the calibration standards (34); - comparing the standard values ​​stored in the control device (54) with the calibration values ​​and determining correction values ​​to use as a reference for subsequent measurement operations on the measuring device (42); A method characterized by:

17. 17. The method according to claim 16, characterized in that at least one of the portions (28, 29, 30) of the carrier (18) of the calibration device (11) at the calibration position (58) is aligned with a measurement point (47) in a measurement surface (48) of the measuring instrument (42).

18. 18. The method according to claim 16 or 17, characterized in that the alignment of the calibration device (11) at the calibration position (58) is performed using a positioning laser of the measuring device (42) or using a measurement image of an optical device (56) of the measuring device (42).

19. 19. The method according to claim 16, further comprising establishing communication between the calibration device (11) and the measuring device (42) at the calibration position (58) via the data interface (26) of the calibration device (11) and the data interface (55) of the measuring device (42).

20. 20. The method according to any one of claims 16 to 19, characterized in that, based on the selected measurement task, the control device (56) selects the number and / or the corresponding type of calibration standards (34) and controls the transverse movement of the carrier (18) of the calibration device (11) to position the corresponding calibration standards (34) in the measurement position (49).

21. The method according to any one of claims 16 to 20, characterized in that a carrier (18) equipped with said calibration standard (34) is selected or said carrier (18) is equipped with the corresponding selected calibration standard (34).

22. 22. The method according to any one of claims 16 to 21, characterized in that, for calibrating the measuring device (42), the control (17) of the calibration device (11) is controlled by the control device (54), and preferably the calibration standards (34) selected for the measuring task are moved successively into the measuring position (49).

23. 23. The method according to claim 16, further comprising, after performing the calibration of the measuring device (42) using the calibration standard (34) of the calibration device (11), transporting a verification standard that was not used for the calibration of the measuring device (42) to the measurement position (49), storing a verification value by means of the verification standard, and comparing the measured value of the calibrated measuring device (42) with the verification value of the verification standard.

24. 24. The method according to claim 23, characterized in that after detecting the verification value, a measurement is made on the reference object by placing the reference object on a pinhole in the portion (30) or on a pinhole (31) in the portion (29) of the carrier (18) through which the membrane (32) extends, then the reference value of the reference object is compared with the verification value, and if the resulting difference value is greater than a preferably selectable threshold value, a recalibration is initiated.

25. 25. The method according to claim 16, further comprising positioning a measurement support (62) behind the carrier (18) of the calibration device (11) in the calibration position (58) in order to direct the primary beam (45) onto the carrier (18) and arrange a measurement object in the beam direction of the primary beam (45), and the carrier (18) comprises a region (29) with a pinhole (31) covered by a foil (32) or a region (30) with a pinhole (31) for detecting a measurement value, the carrier (18) being positioned at a measurement point (47) from the measurement object and being moved to the measurement point (47) to calibrate the measuring instrument (42) after performing one or more measurements on the measurement object using at least one of the regions (28) with the calibration standard (34).

26. 26. The method according to claim 16, characterized in that after calibration, the calibration device (11), preferably arranged at the calibration position (58), exchanges the carrier (18), inserts an automatic exchange device for receiving measuring objects into the calibration device (11), and successively positions the measuring objects in the measurement positions (49) for measuring them by the calibration device (11).

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