Scanning probe, method, and system

Abstract

To provide a scanning probe that is not easily affected by an error and is relatively inexpensive.SOLUTION: An inductive position detector for stylus position measurement in a scanning probe 300 comprises a coil board configuration arranged along a central axis in the scanning probe 300. The coil board configuration includes a field generating coil configuration 360 that surrounds a hole in the coil board configuration, an upper part axial direction detection coil configuration and a lower part axial direction detection coil configuration, and N upper part rotation detection coils and N lower part rotation detection coils. A disruptor configuration 350 coupled with a stylus 306 includes a cylindrical disruptor element that is configured to move and fit within the hole of the coil board configuration, and moves along a Z-axis direction and an X-Y direction in a disruptor motion volume. The field generating coil configuration 360 generates a changing magnetic flux, and a coil signal indicates the cylindrical disruptor element and / or the position of the stylus 306.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of U.S. patent application Ser. No. 16 / 557,719, filed Aug. 30, 2019, entitled "INDUCTIVE POSITION DETECTION CONFIGURATION FOR INDICATING A MEASUREMENT DEVICE STYLUS POSITION," which is incorporated herein by reference in its entirety. U.S. patent application Ser. No. 16 / 557,719 is a continuation-in-part of U.S. patent application Ser. No. 16 / 178,295, filed Nov. 1, 2018, entitled "INDUCTIVE POSITION DETECTION CONFIGURATION FOR INDICATING A MEASUREMENT DEVICE STYLUS POSITION."

[0002] The present disclosure relates to precision measurement, and more particularly to an inductive sensing arrangement for use in a probe used in a coordinate measuring machine. [Background technology]

[0003] A coordinate measuring machine (CMM) can obtain measurements of an inspected workpiece. One exemplary prior art CMM is described in U.S. Pat. No. 8,438,746, which is incorporated herein by reference in its entirety, and includes a probe for measuring the workpiece, a translation mechanism for moving the probe, and a controller for controlling its movement. A CMM with a surface scanning probe is described in U.S. Pat. No. 7,652,275, which is incorporated herein by reference in its entirety. As disclosed therein, a mechanical contact probe or an optical probe can scan the surface of a workpiece.

[0004] A CMM using a mechanical contact probe is also described in U.S. Pat. No. 6,971,183, which is incorporated herein by reference in its entirety. The probe disclosed therein includes a stylus having a surface contact portion, an axial translation mechanism, and a rotational translation mechanism. The axial translation mechanism includes a translation member that allows the contact portion to move in a central axis direction of the scanning probe (also referred to as the Z direction or axial direction). The rotational translation mechanism includes a rotational member that allows the contact portion to move perpendicular to the Z direction. The axial translation mechanism is nested within the rotational translation mechanism. The position of the contact portion and / or the surface coordinates of the workpiece are determined based on the displacement of the rotational member and the axial displacement of the translation member.

[0005] Inductive sensing technology is known to be environmentally robust and has various desirable sensing characteristics. It is known to use precision LVDTs and the like to measure the displacement or position of various internal components in mechanical contact probes similar to those described above. However, LVDTs and other known inductive sensors that are accurate enough for use in CMM probes can be rather large and cumbersome to implement, and the associated movement mechanisms and / or displacement detector arrangements can be relatively expensive and / or susceptible to various “cross-coupling” errors (e.g., due to imperfections in the general configuration and / or mechanism and / or detector). U.S. Pat. No. 4,810,966 (the '966 patent), incorporated herein by reference in its entirety, discloses a relatively planar and relatively economical inductive sensor arrangement capable of detecting the three-dimensional position of a nearby conductive target. However, the arrangement disclosed in the '966 patent has several design deficiencies with respect to providing the necessary accuracy and / or form factor to make it well suited for use in a CMM scanning probe. That is, the configuration of the '966 patent lacks the advanced functionality and features necessary to provide a reasonable level of accuracy in modern measurement equipment such as CMM probes. Other problems associated with the use of known inductive sensing systems such as those outlined above in CMM probes include signal / response nonlinearities inherent in the system's displacement response, position errors due to imperfect assembly and alignment, and signal drift due to environmental effects (e.g., due to temperature changes) on the mechanical and electrical components. Improved inductive sensing configurations for use in CMM probes are needed (e.g., displacement detector configurations that are less susceptible to such errors and / or are relatively inexpensive). Summary of the Invention [Means for solving the problem]

[0006] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0007] A scanning probe with three-axis response is provided for use in a measuring machine (such as a CMM) The scanning probe comprises a stylus suspension, a stylus position detection section, and signal processing and control circuitry.

[0008] The stylus suspension comprises a stylus coupling portion coupled to a frame of the scanning probe and configured to be rigidly coupled to the stylus, and a stylus movement mechanism configured to enable axial movement of the stylus coupling portion along an axial direction and rotational movement of the stylus coupling portion about a center of rotation.

[0009] The stylus position detection unit is arranged along a central axis parallel to the axial direction and nominally aligned with the center of rotation, and is based on an inductive detection principle. The stylus position detection unit includes a coil substrate assembly and a disruptor assembly. The coil substrate assembly includes a field-generating coil assembly surrounding a hole in the coil substrate assembly, an upper axial detection coil assembly (TASCC), a lower axial detection coil assembly (BASCC), and N upper rotation detection coils (TRSC) and N lower rotation detection coils (BRSC), where N is an integer greater than 3. Note that "nominal" is a Japanese translation of "nominally," and may mean "nominal, nominal, formal, design," etc.

[0010] The disruptor structure comprises a cylindrical disruptor element configured to move and fit within a bore in the coil substrate structure. The cylindrical disruptor element provides a disruptor region and comprises a conductive cylinder disposed along a central axis of a disruptor movement volume. The cylindrical disruptor element is coupled to the stylus suspension by a coupling structure and moves within the disruptor movement volume relative to an undeflected position in response to deflection of the stylus suspension. The cylindrical disruptor element can be described as moving through an axial range of motion + / -Rz in response to axial movement and moving through respective ranges of motion + / -Rx and + / -Ry along orthogonal X and Y directions generally perpendicular to the axial direction in response to rotational movement. The field-generating coil structure generates a varying magnetic flux generally along the axial direction within the disruptor movement volume in response to a coil drive signal.

[0011] The signal processing and control circuitry is operatively connected to the coils of the stylus position detection section to provide coil drive signals, and is configured to receive signals from the receive coil section comprising respective signal components provided by respective rotational and axial detection coils (i.e., upper axial detection coil, lower axial detection coil, upper rotational detection coil, and lower rotational detection coil) disposed on the upper and lower coil substrates, and is further configured to output signals indicative of the axial and rotational position of the cylindrical disruptor element or stylus relative to the frame or housing of the scanning probe.

[0012] Such a configuration, in accordance with the principles disclosed herein, can provide signal components that are particularly advantageous with respect to removing or correcting certain signal errors and / or signal cross-coupling errors that limit the accuracy of position determination in known economical three-dimensional position indicators based on inductive sensing.

[0013] In some embodiments, the field-generating coil arrangements may comprise first and second field-generating coil arrangements, each respectively surrounding a hole in the coil substrate arrangement and correspondingly surrounding the disruptor movement volume. In some such embodiments, the first and second field-generating coil arrangements may comprise a pair of planar field-generating coils positioned approximately equidistant from a midplane of the disruptor movement volume along the central axis and nominally planar and orthogonal to said central axis. In some such embodiments, the upper and lower axial detection coil arrangements also surround holes in the coil substrate arrangement and correspondingly surround the disruptor movement volume.

[0014] In some such embodiments, the coil substrate structure has an upper portion and a lower portion. The upper portion includes first, second, and third layers, each including an upper axial detector coil structure, a first field-generating coil structure, and N upper rotating detector coils. The lower portion is a mirror image of the upper portion and includes first, second, and third layers, each including a lower axial detector coil structure, a second field-generating coil structure, and N lower rotating detector coils. The coil substrate structure is mounted in a fixed relationship to the frame of the scanning probe, with the lower portion of the coil substrate structure closer to the stylus suspension. The upper and lower portions of the coil substrate structure are nominally parallel to each other and nominally perpendicular to the central axis. The coil substrate structure may include a normalization coil structure having an upper normalization coil as part of the upper portion and a lower normalization coil as part of the lower portion. The normalization coil structure may be utilized to provide measurements of the varying magnetic flux generated by the first and second field-generating coil structures. The top and bottom portions may be part of a single multi-layer printed circuit board.

[0015] In some embodiments, the method includes moving a scanning probe along a surface of the workpiece as disclosed herein, and generating three-dimensional position information based on inductive detection signals generated by the scanning probe as the scanning probe moves along the surface of the workpiece.

[0016] In some embodiments, a system comprises a scanning probe as disclosed herein, a drive mechanism, and a mount configured to couple the scanning probe to the drive mechanism, hi some embodiments, the system comprises a motion controller that controls movement of the drive mechanism.

[0017] Known inductive sensors using nominally planar sensing elements are too inaccurate for precision scanning probe applications. In contrast, inductive sensors utilizing nominally planar sensing elements configured according to various principles disclosed and claimed herein provide robust signal sets that can be used to provide sufficient accuracy for precision scanning probe applications. In particular, embodiments and / or configurations such as those outlined above can provide particularly advantageous signal components with respect to eliminating or correcting certain signal errors and / or signal cross-coupling errors that previously limited the accuracy of position determination in known, economical three-dimensional position indicators based on inductive sensing. In various embodiments according to various principles disclosed and claimed herein, the signal components provided by the various receive coils are particularly advantageous in that they can be processed using relatively fast and simple signal processing to provide a robust and highly accurate three-dimensional position indication. [Brief explanation of the drawings]

[0018] [Figure 1] 1 illustrates various exemplary components of a measurement system including a CMM utilizing a scanning probe as disclosed herein; [Figure 2] FIG. 1 is a block diagram showing various components of a scanning probe coupled to a CMM to provide rotational and axial position signals. [Figure 3] 1A and 1B are diagrams illustrating a portion of a first exemplary embodiment of a stylus suspension coupled to a stylus and a first exemplary embodiment of a stylus position detector for detecting the position of the stylus suspension. [Figure 4] FIG. 4 shows a cross section of one embodiment of the stylus suspension of FIG. 3 contained within the body frame of a scanning probe; [Figure 5] 5 is a partial schematic isometric view of an alternative embodiment of the stylus position detector shown in FIGS. 3 and 4, highlighting particular features in accordance with principles disclosed herein; FIG. [Figure 6] FIG. 6 is a partial schematic isometric view of certain components of the stylus position detector shown in FIG. 5, illustrating their connection to a block diagram of one exemplary embodiment of processing and control circuitry according to the principles disclosed herein. [Figure 7A] 5A-5C depict embodiments of "four complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 7B] 5A-5C depict embodiments of "four complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 7C] 5A-5C depict embodiments of "four complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 7D] 5A-5C depict embodiments of "four complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 7E]5A-5C depict embodiments of "four complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 8A] 5A-5C depict embodiments of "three (or six) complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 8B] 5A-5C depict embodiments of "three (or six) complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 8C] 5A-5C depict embodiments of "three (or six) complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 8D] 5A-5C depict embodiments of "three (or six) complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 8E] 5A-5C depict embodiments of "three (or six) complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 8F] 5A-5C depict embodiments of "three (or six) complementary pairs" of receive coil section and disruptor element configuration patterns according to principles disclosed herein that can be used in the various embodiments of stylus position detection sections shown in FIGS. 3 and / or 4. [Figure 9A]10A and 10B illustrate a portion of an exemplary embodiment of a stylus position detector for detecting the position of a stylus suspension. [Figure 9B] 10A and 10B illustrate a portion of an exemplary embodiment of a stylus position detector for detecting the position of a stylus suspension. [Figure 10] 9C is a partial schematic isometric view of an alternative embodiment of the stylus position detector shown in FIGS. 9A and 9B, highlighting certain features in accordance with principles disclosed herein; FIG. [Figure 11] 11 is a partial schematic isometric view of an alternative embodiment of the stylus position detector shown in FIG. 10, highlighting certain features in accordance with principles disclosed herein. [Figure 12A] 10A and 10B illustrate a portion of an exemplary embodiment of a stylus position detector for detecting the position of a stylus suspension. [Figure 12B] 10A and 10B illustrate a portion of an exemplary embodiment of a stylus position detector for detecting the position of a stylus suspension. [Figure 13A] 1 is a partial schematic isometric view of an exemplary embodiment of a stylus position detector highlighting particular features in accordance with principles disclosed herein; [Figure 13B] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 13C] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 13D] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 13E] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 13F] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 14A]10 illustrates exemplary frequency shift and off-axis crosstalk characteristics associated with various embodiments of a stylus position detector. [Figure 14B] 10 illustrates exemplary frequency shift and off-axis crosstalk characteristics associated with various embodiments of a stylus position detector. [Figure 14C] 10 illustrates exemplary frequency shift and off-axis crosstalk characteristics associated with various embodiments of a stylus position detector. [Figure 14D] 10 illustrates exemplary frequency shift and off-axis crosstalk characteristics associated with various embodiments of a stylus position detector. [Figure 15A] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 15B] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 15C] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 16] 1 is a partial schematic isometric view of an exemplary embodiment of a stylus position detector highlighting particular features in accordance with principles disclosed herein; [Figure 17A] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 17B] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 18A] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 18B] 1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; [Figure 18C]1 is a schematic diagram illustrating a portion of an exemplary embodiment of a stylus position detector, highlighting particular features in accordance with principles disclosed herein; DETAILED DESCRIPTION OF THE INVENTION

[0019] 1 is a diagram illustrating various exemplary components of a measurement system 100 including a CMM 200 utilizing a scanning probe 300 as disclosed herein. The measurement system 100 includes an operation unit 110, a motion controller 115 for controlling the movement of the CMM 200, a host computer 120, and the CMM 200. The operation unit 110 is coupled to the motion controller 115 and may include a joystick 111 for manually operating the CMM 200. The host computer 120 is coupled to the motion controller 115 and operates the CMM 200 and processes measurement data of the workpiece W. The host computer 120 includes input means 125 (e.g., a keyboard, etc.) for inputting, for example, measurement conditions, and output means 130 (e.g., a display, printer, etc.) for outputting, for example, measurement results.

[0020] CMM 200 includes a drive mechanism 220 disposed on base plate 210 and a mount 224 for mounting scanning probe 300 to drive mechanism 220. Drive mechanism 220 includes X-axis, Y-axis, and Z-axis slide mechanisms 222, 221, and 223, respectively, for moving scanning probe 300 in three dimensions. A stylus 306 attached to the end of scanning probe 300 includes a contact portion 348. As described in more detail below, stylus 306 is attached to a stylus suspension of scanning probe 300, which allows contact portion 348 to freely change its position in three directions as contact portion 348 moves along a measurement path on the surface of workpiece W.

[0021] Figure 2 is a block diagram showing various components of a scanning probe 300 coupled to a CMM 200 and providing rotational (e.g., X, Y) and axial (e.g., Z) position signals. The scanning probe 300 comprises a probe body 302 (e.g., comprising a frame) incorporating a stylus suspension 307 and a stylus position detection portion 311 (i.e., the stylus suspension 307 is coupled to the frame of the scanning probe 300). The stylus suspension 307 comprises a stylus coupling portion 342 and a stylus movement mechanism 309. The stylus coupling portion 342 is rigidly coupled to a stylus 306. The stylus movement mechanism 309 is configured to allow axial movement of the stylus coupling portion 342 and attached stylus 306 along an axial direction, and rotational movement of the stylus coupling portion 342 and attached stylus 306 about a center of rotation, as described in more detail below with respect to Figures 3 and 4. The scanning probe 300 includes signal processing and control circuitry 380 which is connected to the stylus position detector 311 to control its operation and to perform associated signal processing, as will be explained in more detail below.

[0022] As shown in FIG. 2 , the stylus position detection section 311 uses an inductive detection principle and includes a receive coil section 370, a field-generating coil arrangement 360, and a disruptor element 351 (which is part of a disruptor arrangement 350 and may comprise multiple sections in some embodiments). The receive coil section 370 may include a rotational detection coil section (also called a rotational detection coil) RSC and an axial detection coil arrangement ASCC. Briefly, the moving disruptor element 351 (or, more generally, the disruptor arrangement 350) causes position-dependent changes in the varying magnetic field (variable magnetic flux) generated by the field-generating coil arrangement 360. The receive coil section 370 responds to the varying magnetic field and changes therein caused by the disruptor element 351. In particular, the rotational detection coil section RSC outputs at least first and second rotational signal components RSigs indicative of the rotational position (e.g., X and Y position signals) of the stylus coupling section 342 on corresponding signal lines, as described in more detail below with reference to, for example, Figures 3, 5, and 6. And, the axial detection coil arrangement ASCC outputs one or more axial signal components ASigs indicative of the axial position (e.g., Z position signal) of the stylus coupling section 342 on corresponding signal lines. In various embodiments, the signal processing and control circuitry 380 can receive the rotational signal components RSigs and the axial signal components ASigs and perform various levels of associated signal processing in various embodiments. For example, in one embodiment, the signal processing and control circuitry 380 can combine and / or process the signal components from the various receiving coils in various relationships and provide the results in a desired output format as rotational and axial position signal outputs RPSOut and APSOut via the mounting section 224. One or more receivers (e.g., CMM 200, motion controller 115, host computer 120, etc.) may receive the rotational and axial position signal outputs RPSOut and APSOut, and one or more associated signal processing and control units may be utilized to determine the three-dimensional position of the contact portion of the stylus coupling portion 342 and / or attached stylus 306 as the contact portion 348 moves along the surface of the workpiece W being measured.

[0023] FIG. 3 is a partial schematic diagram illustrating a portion of a first exemplary embodiment of a stylus suspension 407 coupled to a stylus 406, along with a partial schematic cross-sectional view of the first exemplary embodiment of the stylus suspension 407 and / or stylus position detection portion 411 for detecting the position of the stylus 406. (Note that the stylus position detection portion 411 is disposed along a central axis CA that is parallel to the axial direction (Z direction) and nominally aligned with a center of rotation RC, as shown in FIG. 3.) It will be understood that certain numbered components 4XX in FIG. 3 correspond to and / or have similar operation to similarly numbered corresponding components 3XX in FIG. 2 and can be understood by analogy thereto and otherwise described below. This numbering scheme, indicating components of similar design and / or function, also applies to FIGS. 4-8F below. As shown in FIG. 3, the stylus suspension 407 includes a stylus-moving mechanism 409 and a stylus coupling portion 442. The stylus coupling portion 442 is configured to be rigidly coupled to a stylus 406 having a contact portion 448 for contacting a surface S of a workpiece W (not shown).

[0024] As will be described in more detail below with respect to Figure 4, the stylus movement mechanism 409 is mounted to the frame of the scanning probe and is configured to allow axial and rotational movement of the stylus coupling portion 442 and attached stylus 406 so that the contact portion 448 can vary its position in three directions along the shape of the surface S. For purposes of illustration, the vertical and horizontal directions in the plane of the paper in Figure 3 are defined as the Z and Y directions, respectively, and the direction normal to the plane of the paper is defined as the X direction. The direction of the central axis CA of the scanning probe 300, also referred to as the axial direction, coincides with the Z direction in this figure.

[0025] 3 shows the rotational movement portion of the stylus movement mechanism 409, which includes a rotating member 436, a bending element 440, and a moving member 412 disposed within the rotating member 436. As described in more detail below in FIG. 4, the bending element 440 enables rotational movement of the rotating member 436 about a center of rotation RC. As described in more detail below, in various embodiments, rotational detection coils TRSCi and BRSCi (where i is an index integer that identifies a particular coil) and the stylus position detection portion 411 can detect the rotational position of the disruptor element 451, thereby detecting the rotational position (e.g., in the X and Y directions) of the moving member 412, and axial detection coil arrangements (also referred to as axial detection coils) TASCC and BASCC can detect the axial position of the disruptor element 451, thereby detecting the axial position (e.g., in the Z direction) of the moving member 412.

[0026] As shown in Figure 3, a first exemplary embodiment of the stylus position detection unit 411 comprises a disruptor element 451 (or, more generally, a disruptor arrangement 450) coupled to a moving member 412 and moving relative to a frame of the scanning probe (e.g., a frame included as part of the scanning probe body) within a disruptor movement volume MV located between the upper and lower coil substrates 471T and 471B, respectively. As shown in Figure 3, the moving member 412 extends through and moves within a hole 472 located along a central axis CA of the lower coil substrate (471B) (i.e., the moving member 412 passes through a hole 472 located in the lower coil substrate 471B along the central axis CA and extends approximately along the central axis CA). The attached disruptor element 451 moves within the disruptor movement volume MV relative to an undeflected position UNDF in response to deflections of the stylus suspension 407 and the moving member 412.

[0027] Various other components of the stylus position detection section 411, such as the receive coil section 470 and the field generating coil arrangement 460, may be fixed relative to the frame unless otherwise noted. In the embodiment shown in FIG. 3, the field generating coil arrangement 460 comprises a single planar field generating coil (also referred to as a field generating coil section) 461 disposed approximately in the midplane of the disruptor movement volume MV and nominally planar and perpendicular to the central axis CA. As outlined above with reference to FIG. 2, the receive coil section 470 may generally comprise a rotational detection coil section (also referred to as a rotational detection coil) RSC and an axial detection coil arrangement ASCC. The rotational position detection arrangement (rotational detection coil section) RSC generally comprises upper and lower rotational detection coils TRSCi and BRSCi. Only two upper rotational detection coils TRSC1 and TRSC2 and two lower rotational detection coils BRSC1 and BRSC2 are shown in the cross section shown in FIG. 3. These rotational detection coils may provide signal components indicative of the position of the disruptor element 451 along the Y direction. In particular, those signal components vary with, and are therefore indicative of, the amount of displacement ΔY of the disruptor element 451 along the Y-direction. The displacement ΔY determines the amount of relative “overlap” between the disruptor element 451 and the various rotational detection coils TRSCi and BRSCi, thereby determining the amount of coupling to the varying magnetic field generated by the field generating coils 461 (which determines the resulting signal components). Other rotational detection coils (not shown) can provide signal components indicative of the position of the disruptor element 451 along the X-axis direction. The signal components of the various rotational detection coils may also be undesirably sensitive to their local “operating gap” OG relative to the disruptor element 451, as shown in FIG. 3 for the upper rotational detection coil TRSC2. However, such undesirable gap sensitivity can be substantially eliminated or compensated for in accordance with various principles disclosed herein, as further described below.

[0028] The axial detector coil arrangement ASCC generally comprises an upper axial detector coil arrangement TASCC and a lower axial detector coil arrangement BASCC. In the embodiment shown in FIG. 3, the upper axial detector coil arrangement TASCC comprises a single upper axial detector coil at least partially surrounding the central axis CA, and the at least one lower axial detector coil comprises a single lower axial detector coil at least partially surrounding the central axis, as shown. These axial detector coils are always fully "overlapped" by the disruptor element 451. Thus, their signal components are nominally responsive only to, and indicative of, the position of the disruptor element 451 along the axial or Z direction. The generation of the various signal components is described in more detail below with reference to FIGS. 5 and 6.

[0029] Similar to the operation outlined above with reference to FIG. 2, during operation, the moving disruptor element 451 induces position-dependent local variations in the axially varying magnetic field generated by the field generating coils 461. The receive coil section 470, as described above with reference to FIG. 2 and in further detail below, responds to the varying magnetic field induced by the disruptor element 451 and variations therein and outputs rotational signal components RSigs and axial signal components ASigs that may be processed to determine the rotational position (e.g., Y and X positions, and corresponding signals) and axial position (e.g., Z position) of the disruptor element 451. It will be appreciated that the position of the disruptor element 451 is related by known geometry to the position of the stylus coupling portion 442 and / or its contact portion 448. For example, for small rotation angles, for an illustrated movement or displacement ΔY of the disruptor element 451 along the Y direction away from null (e.g., from the undeflected position UNDF), ΔY=Hθ Y (Formula 1)

[0030] where H is the distance from the center of rotation RC to the nominal plane of the disruptor element 451, and θ Yis the slope of the rotational movement of the rotating member 436 (and moving member 412) in a plane parallel to the Y direction (i.e., rotation about an axis parallel to the X axis at the center of rotation RC). In various embodiments, when larger rotation angles are used, accurate similar expressions for larger rotation angles may be used as known in the art. The slope component θ of the rotational movement Y Y is the Y-direction movement or displacement Y of the contact portion 448 of the stylus 406 away from the null (e.g., corresponding to the undeflected position UNDF) in relation to STYLUS can be approximated as follows: ΔY STYLUS =θ Y *(h S +l S ) (Formula 2)

[0031] where h S is the distance from the end of the stylus coupling portion 442 to the center of rotation RC, and l S is the length of the stylus 406. Combining Equations 1 and 2, the ratio of the displacement ΔY of the disruptor element 451 to the displacement of the contact portion 448 in the Y direction can be approximated as: ΔY / ΔY STYLUS = H / (h S +l S ) (Formula 3)

[0032] It will be understood that the translation component of the X coordinate is similar to the above equation and will not be described in further detail herein. S can utilize equations (e.g., for system trigonometry) to determine the XY position of the contact 448 based on the XY detection spot position. In terms of Z coordinate displacement or position component, the Z displacement ΔZ of the stylus contact (e.g., contact 448) STYLUS The displacement ΔZ (not shown) of the disruptor element 451 along the axial or Z direction away from the null (e.g., corresponding to the undeflected position UNDF) relative to can be approximated as: ΔZ / ΔZ STYLUS ≒ 1 (Equation 4)

[0033] FIG. 4 is a partial schematic diagram illustrating an embodiment of a stylus position detection portion 511 similar to the stylus position detection portion 411 shown in FIG. 3 , as well as a cross section of an embodiment of a stylus suspension 407′ that can be used as the stylus suspension 407 shown in FIG. 3 , and a signal processing and control circuit 480. The above components are shown contained within a frame 408 of the probe body 402 of the scanning probe 400. The upper and lower coil boards 571T, 571B and the field-generating coils 561 of the stylus position detection portion 511 or their substrates (e.g., printed circuit boards) are positioned for proper operation in the scanning probe 400 using an alignment and mounting portion 417 or other known techniques. Various signal connections associated with the stylus position detection portion 511 may be provided by connectors (e.g., flex prints and / or wire connections) 419, etc., in accordance with known techniques. In some embodiments, some or all of the signal processing and control circuitry 480 may be provided as a separate circuit assembly, as shown in FIG. 4 . In other embodiments, some or all of the signal processing and control circuitry 480 may be combined on board the stylus position detection portion 511, if desired.

[0034] As shown in Figure 4, the stylus suspension 407' comprises a stylus movement mechanism 409 and a stylus coupling portion 442 coupled to the stylus 406. The stylus movement mechanism 409 comprises a moving member 412, a rotating member 436, a flexure element 440 coupled to the frame 408 to support and allow rotational movement of the rotating member 436, and flexure elements 414 and 415 (i.e. referred to as first flexure elements) that support and couple the moving member 412 to the rotating member 436 to allow axial movement of the moving member 412. The scanning probe 400 comprises a stylus position detection portion 511, the components and operation of which are described in more detail below with reference to Figure 5, for determining the position and / or movement of the stylus movement mechanism 409 and / or a contact portion 448 of the stylus 406.

[0035] The flexure element 440 (i.e., referred to as the second flexure element) can be disposed between the respective planes of the pair of flexure elements 414 and 415 (i.e., referred to as the first flexure elements) in the axial direction O. Appropriate flexure designs for the flexure elements 414, 415, and 440 can be determined according to principles known in the art. For example, one possible embodiment is shown in co-pending, commonly assigned U.S. patent application Ser. No. 14 / 973,376, entitled "Measurement Device With Multiplexed Position Signals," filed December 17, 2015, and incorporated herein by reference in its entirety. The rotating member 436 can have a shape symmetrical with respect to the second flexure element 440 and can integrally comprise two ring portions 436A, two connecting portions 436B, and one cylindrical portion 436C. The peripheries of the first flexure elements 414 and 415 are fixed to the ring portion 436A. Connecting portion 436B extends inside ring portion 436A to connect to hollow cylindrical portion 436C. First bending elements 414 and 415 may be positioned at symmetrical distances relative to second bending element 440, although such an embodiment is exemplary only and not limiting.

[0036] An axial movement mechanism 410 comprising a movement member 412 is supported inside the rotating member 436, and the rotating member 436 and the axial movement mechanism 410 together form a movement module that is part of the stylus movement mechanism 409. The axial movement mechanism 410 enables the contact portion 448 to move in the axial direction O. The rotational movement mechanism 434 comprising the rotating member 436 enables the contact portion 448 of the stylus 406 to move transversely (e.g., approximately perpendicularly) to the axial direction O by rotational movement about a rotation center RC.

[0037] The moving member 412 integrally comprises a lower portion 412A, a rod portion 412B, and an upper portion 412C. As generally described above with reference to FIG. 3 and described in more detail below with respect to the stylus position detection portion 511 shown in FIG. 5, a disruptor element 551 attached to the upper portion 412C of the moving member 412 functions as both a rotational and axial position indicating element. The rod portion 412B is disposed between a pair of first bending elements 414 and 415. The rod portion 412B is housed in the rotating member 436. The lower portion 412A is formed below the rod portion 412B, and a stylus coupling portion 442 (e.g., a flange member) is attached to the lower portion 412A. A flange portion 444 is provided for mounting the stylus 406. The flange portion 444 and the stylus coupling portion 442 together may provide a removable coupling mechanism (e.g. a kinematic joint or coupling of a known type) that allows for repeatable positioning and disconnection between various styli 406 and the stylus coupling portion 442 (e.g. in the event of a collision that dislodges the stylus, or when intentionally changing styli).

[0038] Figure 5 is a partial schematic isometric view of an alternative embodiment of a stylus position detector 511' similar to the stylus position detector 511 shown in Figure 4, highlighting certain features in accordance with the principles disclosed herein. Stylus position detectors 511' and 511 are similar except for differences in field-generating coil arrangement 560, as described further below. It will be understood that in general, stylus position detector 511' includes certain components similar to those of stylus position detectors 311, 411 and 511 of Figures 2, 3 and 4, and operate similarly except as otherwise described below.

[0039] In the embodiment shown in FIG. 5, the stylus position detection section 511 ′ comprises a receive coil section 570 , a disruptor arrangement 550 comprising disruptor elements 551 , and a field generating coil arrangement 560 .

[0040] In various embodiments, the disruptor element 551 (or, more generally, the disruptor structure 550) may comprise a conductive plate or loop, or parallel conductive plates or loops (e.g., provided on two sides of a printed circuit board and patterned using printed circuit board fabrication techniques), or any other desired operating structure that provides a disruptor area (e.g., an interior area thereof). The disruptor element 551 is disposed along a central axis CA of the disruptor movement volume MV between the upper coil substrate 571T and the lower coil substrate 571B, and is coupled to the stylus suspension 507 by a coupling structure (e.g., comprising the moving member 512). For purposes of explanation, the disruptor element 551 may be described as moving relative to an undeflected position shown in FIG. 5 (see undeflected position UNDF in FIG. 3 ) in response to deflection of the stylus suspension 507 and / or the stylus 506 and / or the moving member 512. The disruptor element may be described as moving in response to axial motion through an axial range of motion of + / -Rz with displacement increments ΔZ, and in response to rotational motion through an axial range of motion of + / -Rx and + / -Ry with displacement increments ΔX and ΔY along orthogonal X and Y directions, respectively, orthogonal to the axial (Z) direction. Specified or expected ranges of motion are described in more detail below.

[0041] The receive coil section 570 may comprise a planar upper coil substrate 571T comprising N upper rotating detector coils TRSC (e.g., N=4, TRSC1-TRSC4) and an upper axial detector coil arrangement TASCC (e.g., comprising a single illustrated individual coil in this embodiment), and a planar lower coil substrate 571B comprising N lower rotating detector coils BRSC (e.g., N=4, BRSC1-BRSC4) and a lower axial detector coil arrangement BASCC (e.g., comprising a single illustrated individual coil in this embodiment). The upper and lower coil substrates 571T and 571B are mounted in fixed relationship to the frame of the scanning probe, with the lower coil substrate closer to the stylus 506 and / or stylus suspension 507. The upper and lower coil substrates 571T and 571B are nominally parallel to each other and nominally perpendicular to and spaced apart along the central axis CA, and a disruptor moving volume MV may be disposed between them. While the various detection coils shown in FIG. 5 are represented by "closed loops" for ease of explanation, it will be understood that all coils comprise windings or conductors having first and second connected ends configured to act as one or more inductively coupled "turns" (e.g., as represented in FIG. 6).

[0042] The field-generating coil arrangement (e.g., field-generating coil arrangement 560) generally comprises at least one first field-generating coil positioned proximate to the disruptor movement volume MV and nominally planar and orthogonal to the central axis CA. In contrast to the single planar field-generating coil 461 in the embodiment shown in Figure 3 (which is located approximately in the mid-plane of the disruptor movement volume MV), in the embodiment shown in Figure 5, the field-generating coil arrangement 560 comprises a pair of planar field-generating coils 561T and 561B (located on upper and lower coil substrates 571T and 571B, respectively) positioned approximately equidistant from the mid-plane of the disruptor movement volume MV along the central axis CA and nominally planar and orthogonal to the central axis CA. Generally speaking, either field-generating coil configuration 460 or 560 can be used in receive coil section 570 (or other receive coil sections disclosed herein) if the field-generating coil configuration comprises at least a first field-generating coil configured such that the projection of its (i.e., of the first field-generating coil) coil area along the axial direction (Z direction) encompasses conductive plates or loops that provide the disruptor area of ​​disruptor configuration 550 (e.g., of disruptor element 551) and the coil areas of all rotational and axial detection coils RSCi and ASCC disposed on upper and lower coil substrates 571T and 571B (i.e., the projection of the coil area of ​​the first field-generating coil along the axial direction encompasses conductive plates or loops that provide the disruptor area and the coil areas of all rotational and axial detection coils RSCi and ASCC disposed on the coil substrate configuration). In such a case, the field generating coil arrangement is configured to generate a varying magnetic flux generally along an axial direction within the disruptor movement volume MV in response to the coil drive signals, as desired for operation of the stylus position detection portion 511'.The various field-generating coils shown in FIG. 5 are represented for ease of explanation as one single "closed loop" comprising a wide, flat conductive trace (with edges shown), but it will be understood that in an actual device (e.g., as represented in FIG. 6 ) all coils will comprise windings or conductors having first and second connection ends and will be configured to operate as one or more field-generating "turns."

[0043] As shown in FIG. 5, the projection of the disruptor element 551 along the axial direction through the internal coil region of the upper axial detector coil arrangement TASCC (e.g., as shown by the thin dashed line PRJ in FIG. 5) defines an upper axial detector overlap region TASOA (indicated by the dot pattern filling that internal coil region). Similarly, the projection of the disruptor element 551 along the axial direction through the internal coil region of the lower axial detector coil arrangement BASCC defines a lower axial detector overlap region BASOA (indicated by the dot pattern filling that internal coil region). Similarly, the projection of the disruptor element 551 along the axial direction through the internal coil region of each upper rotating detector coil TRSCi (e.g., TRSC1-TRSC4), where i is an individual coil identification index ranging from 1 to N, defines a respective upper rotating coil detector overlap region TRSCOAi (e.g., TRSCOA1-TRSCOA4). As shown by the dot patterns filling the various respective overlap regions in FIG. 5, the projection of the disruptor element 551 along the axial direction through the internal coil region of each lower rotating detection coil BRSCi (e.g., BRSC1-BRSC4) defines a respective lower rotating coil detection overlap region BRSCOAi (e.g., TRSCOA1-TRSCOA4).

[0044] Regarding the axial position detection in the stylus position detection unit (e.g., 511′), In accordance with the principles described and claimed herein, the receive coil sections (e.g., 570) and disruptor elements (e.g., 551) are generally configured to provide upper and lower axial detection overlap areas, TASOA and BASOA, respectively, where the respective amounts of overlap, TASOA and BASOA, do not vary with or depend on the position of the disruptor element 551 within its operating ranges of motion, + / -Rz, + / -Rx, and + / -Ry. (It will be understood that for a particular scanning probe, the operating range of motion will be defined or specified, if necessary, in combination with the configuration of the probe's particular stylus position detection sections to meet this requirement.) In this manner, the signal components generated by the upper and lower axial detection coil arrangements, TASCC and BASCC, are nominally independent of rotational motion (i.e., the position of the disruptor element 551 along the X and Y directions) and are nominally sensitive only to changes in "proximity" or gap with the disruptor element 551. Note that the change in "proximity" or gap varies with the axial (Z) position or displacement ΔZ of the disruptor element 551. During operation, current induced in the disruptor element 551 by the changing magnetic field of the field generating coil arrangement 560 causes an opposing magnetic field. Generally, as the disruptor element 551 moves upward along the axial (Z) direction of FIG. 5, the opposing magnetic field couples more strongly to the upper axial detection coil arrangement TASCC, reducing its signal component resulting from the changing magnetic field. Conversely, the opposing magnetic field couples more weakly to the lower axial detection coil arrangement BASCC, increasing its signal component resulting from the changing magnetic field. By convention used in this disclosure, a signal component SIGTA SCC may be referred to as the signal component resulting from a particular upper axial detection coil arrangement (or coil), such as TASCC.

[0045] It can be seen that in the undeflected position UNDF, the net signal components SIGTASCC and SIGBASCC are approximately balanced. For small displacements ΔZ, such as those expected during operation, the net signal components SIGTASCC and SIGBASCC can vary approximately linearly and inversely relative to one another. Specific considerations related to the degree of such signal nonlinearity are discussed further below. In one embodiment, the axial displacement or position ΔZ can be indicated by or correspond to a signal relationship. ΔZ = function [(SIGBASCC-SIGTASCC) / (SIGBASCC+SIGTASCC)] (Equation 5)

[0046] This signal relationship is merely exemplary and not limiting. In various embodiments, this signal relationship may be adjusted or compensated for by additional calibration or signal processing operations, as needed, including operations to reduce the effects of geometric and / or signal cross-coupling between various displacement directions or signal components. In various embodiments, the upper axial detection coil configuration may include at least one upper axial detection coil positioned closer to the central axis than the upper rotation detection coil(s), rather than one of the N upper rotation detection coils. The at least one upper axial detection coil and the disruptor element are characterized such that the at least one upper axial detection coil has an internal coil area smaller than the disruptor element, and the projection of the disruptor element along the axial direction completely fills the internal coil area of ​​the at least one upper axial detection coil for any position of the disruptor element within the operational range of motion + / -Rz, + / -Rx, and + / -Ry. This ensures that the upper axial detection overlap area (TASOA) does not change with the position of the disruptor element. Similarly, in various such embodiments, the lower axial detector coil arrangement may not be one of the N lower rotation detector coils, but may comprise at least one lower axial detector coil located closer to the central axis than the lower rotation detector coil. The at least one lower axial detector coil and the disruptor element are characterized such that the at least one lower axial detector coil has an internal coil area smaller than the disruptor element, and the projection of the disruptor element along the axial direction completely fills the internal coil area of ​​the at least one lower axial detector coil for any position of the disruptor element within the operational ranges of travel + / -Rz, + / -Rx, and + / -Ry. This ensures that the lower axial detector overlap area BASOA does not change with the position of the disruptor element. It will be appreciated that the particular embodiment of the stylus position detector 511′ shown in FIG. 5 , in which the upper axial detector coil arrangement TASCC and the lower axial detector coil arrangement BASCC each comprise a single detector coil, fits this description.It will be understood that various configurations of the upper and lower axial detection coil arrangements TASCC and BASCC can be used, and the particular configuration shown in Figure 5 is exemplary only and not limiting. Various alternative configurations are described with reference to other figures below.

[0047] In accordance with the principles described and claimed herein, for rotational position detection in a stylus position detection section (e.g., 511′), a receive coil section (e.g., 570) and a disruptor element (e.g., 551) are generally configured to provide N complementary pairs of rotational detection coils CPi (e.g., CP1-CP4, N=4) comprising an upper rotational detection coil TRSCi and a lower rotational detection coil BRSCi, respectively, where for any complementary pair CPi for any disruptor element displacement increment within the operational travel ranges + / -Rz, + / -Rx, and + / -Ry, the magnitude of the change in overlap area TRSCOAi and BRSCOAi associated with that disruptor element displacement increment is nominally the same for that complementary pair. (It will be appreciated that for a particular scanning probe, its operational travel range will be determined or specified, if necessary to meet this requirement, in combination with its particular stylus position detection unit configuration.) The table CPTable in Figure 5 shows each rotation detection coil TRSCi and BRSCi for each complementary pair CPi in the embodiment shown in Figure 5.

[0048] By adhering to the foregoing principles, the complementary pair CPi shown in FIG. 5 can be used to compensate for or eliminate certain cross-coupling errors and / or simplify the signal processing required to provide accurate rotational position or displacement measurements (e.g., along the X and / or Y directions). In particular, pairs of signal components generated in the complementary pair CPi of rotational detection coils in the embodiment shown in FIG. 5 may be combined or processed in a relationship that provides a resultant signal that is nominally insensitive to changes in "proximity" or gaps between the individual coils of the complementary pair and the disruptor element 551. That is, the resultant signal may be insensitive to the axial (Z) position or displacement ΔZ of the disruptor element 551, and nominally sensitive only to rotational position or displacement (e.g., along the X and / or Y directions), as described in more detail below. 5, it will be appreciated that a displacement of disruptor element 551 with a displacement component ΔY along the Y-axis direction increases (or decreases) the overlap area TRSCOA2 and BRSCOA2 in complementary pair CP2 and decreases (or increases) the overlap area TRSCOA1 and BRSCOA1 in complementary pair CP1. Similarly, a displacement of disruptor element 551 with a displacement component ΔX along the X-axis direction increases (or decreases) the overlap area TRSCOA3 and BRSCOA3 in complementary pair CP3 and decreases (or increases) the overlap area TRSCOA4 and BRSCOA4 in complementary pair CP4.

[0049] As outlined above, during operation, currents induced in the disruptor elements 551 by the varying magnetic fields of the field generating coil arrangements 560 cause opposing magnetic fields. In general, the signal component SIGTRSCi (or SIGBRSCi) generated in any rotational detection coil TRSCi (or BRSCi) decreases as the proximal portion of the disruptor element 551 approaches that rotational detection coil along the axial direction or increases its overlap area TRSCOAi (or BRSCOAi) with the rotational detection coil.

[0050] For complementary pairs CP1-CP4 shown in FIG. 5 (the coils of complementary pair CPi are identical and axially aligned), it can be seen that in the illustrated undeflected position UNDF, the signal components of each complementary pair (e.g., SIGTRSC1 and SIGBRSC1) are approximately balanced. In accordance with the principles outlined above, for small displacements ΔZ of the portion of disruptor element 551 proximate to a complementary pair (e.g., CP1), such as would be expected during operation, the net signal components (e.g., SIGTRSC1 and SIGBRSC1) can vary approximately linearly and inversely relative to one another. Thus, the sum of such signals of complementary pair CPi may be nominally insensitive to ΔZ associated with the proximate portion of disruptor element 551. 5, the edges of the disruptor elements 551 can be parallel to the X and Y directions such that within the operational travel ranges + / -Rx and + / -Ry, displacement components in the Y direction do not alter the rotating coil detection overlap areas TRSCOA3, BRSCOA3, and / or TRSCOA4 and BRSCOA4, and displacement components in the X direction do not alter the rotating coil detection overlap areas TRSCOA2, BRSCOA2, and / or TRSCOA1 and BRSCOA1. Thus, in one embodiment, the rotational displacement or position component ΔX along the X direction, ideally regardless of ΔZ and / or ΔY, can be indicated by or correspond to the following signal relationship: ΔX = function [(SIGTRSC3+SIGBRSC3)-(SIGTRSC4+SIGBRSC4)]÷ [(SIGTRSC3+SIGBRSC3)+(SIGTRSC4+SIGBRSC4)] (Formula 6)

[0051] Similarly, in one embodiment, the rotational displacement or position component ΔY along the Y direction, ideally regardless of ΔZ and / or ΔX, can be represented by or correspond to the following signal relationship: ΔY = function [(SIGTRSC2+SIGBRSC2)-(SIGTRSC1+SIGBRSC1)]÷ [(SIGTRSC2+SIGBRSC2)+(SIGTRSC1+SIGBRSC1)] (Formula 7)

[0052] These signal relationships are by way of example only and are not limiting. In various embodiments, these signal relationships are adjusted or compensated for, as needed, by additional calibration or signal processing operations that include operations to reduce the effects of geometric and / or signal cross-coupling between various displacement directions or signal components.

[0053] In some particularly advantageous embodiments, the receive coil section (e.g., 570) and disruptor element (e.g., 551) are configured such that, for a displacement increment of any complementary pair CPi and any disruptor element within the operational ranges of travel + / -Rz, + / -Rx, and + / -Ry, both the magnitude and sign of the change in overlap region TRSCOAi and BRSCOAi associated with that disruptor element displacement increment are the same for that complementary pair. In some such embodiments, the receive coil section is configured such that each complementary pair CPi includes an upper rotation detection coil TRSCi and a lower rotation detection coil BRSCi that are characterized by nominally matching shapes of their internal regions when projected along the axial direction. It will be understood that the particular embodiment of the stylus position detection section 511′ shown in FIG. 5 fits this description. However, it will be understood that the particular configuration shown in FIG. 5 is illustrative only and not limiting, and that various configurations of complementary pairs may be used. Various alternative configurations are described below with reference to the other figures.

[0054] In some particularly advantageous embodiments, the receive coil section (e.g., 570) and disruptor element (e.g., 551) are configured such that the disruptor element has at least N straight sides, and for any respective complementary pair CPi, each of the disruptor element's straight sides intersects both the upper rotation detection coil TRSCi and the lower rotation detection coil BRSCi of that respective complementary pair. In some such embodiments, N=4, and the at least N straight sides comprise four sides arranged parallel to the sides of a rectangle or square. It will be appreciated that the particular embodiment of the stylus position detection section 511′ shown in FIG. 5 fits this description. However, it will be understood that various combinations of complementary pair configurations and disruptor element edge configurations can be used, and the particular configuration combination shown in FIG. 5 is merely exemplary and not limiting. Various alternative configuration combinations are described with reference to other figures below.

[0055] FIG. 6 is a partial, schematic isometric view of certain components of the stylus position detection unit 511′ shown in FIG. 5 , including connections CONN shown generally in a block diagram of one exemplary embodiment of a signal processing and control circuit 680 according to the principles disclosed herein. As shown in FIG. 6 , the signal processing and control circuit 680 is operatively connected to the various coils of the stylus position detection unit 511′. In the embodiment shown in FIG. 6 , the signal processing and control circuit 680 comprises a digital controller / processor 681 that can manage or exchange operations for various timing and signal connections between its various interconnected components. The digital controller / processor 681 comprises a drive signal generator 682, an amplifier / switching unit 683, a sample and hold unit 684, a multiplexing unit 685, and an A / D conversion unit 686. The digital controller / processor 681 can also perform various digital signal processing operations to determine the output signals APSOut and RPSOut, as outlined above with reference to FIG. 2 and further described below. The design and operation of signal processing and control circuitry 680 can generally be appreciated and understood by those skilled in the art according to known principles. For example, in one embodiment, the various components of signal processing and control circuitry 680 can be designed and operated similarly to corresponding components disclosed in U.S. Patent No. 5,841,274, the entire contents of which are incorporated herein by reference. Accordingly, the operation of the illustrated signal processing and control circuitry 680 will only be briefly described herein.

[0056] During operation, the drive signal generator 682 operates to provide a varying coil drive signal Dsig (e.g., pulses) to the field-generating coil arrangement 560. In response to the coil drive signal, the field-generating coil arrangement 560 generates a varying magnetic flux generally along the axial direction of the disruptor movement volume MV. In the illustrated configuration, the upper field-generating coil 561T and the lower field-generating coil 561B are configured to provide a mutually constructive varying magnetic flux. The amplifier / switching section 683 is configured to input signal components RSIGs and ASIGs from the receive coil section 570. The receive coil section 570 comprises respective signal components (e.g., the previously outlined signal components SIGTASCC, SIGBASCC, SIGTRSC1-SIGTRSC4, and SIGBRSC1-SIGBRSC4) provided by respective rotational and axial detection coils disposed on the upper and lower coil substrates. In some embodiments, amplifier / switching unit 683 may comprise switching circuitry that combines various analog signals to provide various desired sum or difference signals (e.g., via appropriate serial or parallel connections, etc.), e.g., as defined by the relationships shown in Equations 5-7, etc. However, in other embodiments, amplifier / switching unit 683 may perform only amplification and signal conditioning operations (and possibly signal inversion operations), with all signal combining operations being performed by other circuit portions.

[0057] The sample and hold unit 684 receives the various analog signals from the amplifier / switching unit 683 and performs sample and hold operations according to known principles, e.g., to simultaneously sample and hold all respective signal components arising from the various respective detection coils of the receive coil unit 570. In one embodiment, the multiplexing unit 685 can couple the various signals to the A / D converter unit 686 serially and / or in combinations related to various desired signal relationships (e.g., as defined by the relationships shown in Equations 5-7, etc.). The A / D converter unit 686 outputs corresponding digital signal values ​​to the digital controller / processor 681. The digital controller / processor 681 then processes and / or combines the digital signal values ​​to determine and output output signals APSOut and RPSOut according to various desired relationships (e.g., as defined by the relationships shown in Equations 5-7, etc.). The output signals APSOut and RPSOut indicate at least one axial and rotational position of the disruptor element 551 or the stylus 506 relative to the frame or housing of the scanning probe. In some embodiments, the digital controller / processor 681 may be configured so that the output signals APSOut and RPSOut directly indicate the three-dimensional position of the stylus 506 or its contact portion 548 relative to the frame of the scanning probe. In other embodiments, the digital controller / processor 681 may be configured to output signals that indirectly indicate the three-dimensional position of the stylus 506 or its contact portion 548 relative to the frame of the scanning probe. The host system (e.g., a CMM) then inputs and performs additional processing on such signals to further combine or refine such signals and determine the three-dimensional position of the stylus 506 or its contact portion 548 relative to all coordinate systems used in the scanning probe and / or CMM measurements.

[0058] In embodiments of a stylus position detection section (e.g., 511′) according to the various principles disclosed and claimed herein, it will be appreciated that the signal components provided by the various receive coils of the receive coil section (e.g., 570) are particularly advantageous with respect to removing or correcting certain signal errors and / or signal cross-coupling errors, while using relatively fast and simple signal processing to provide a robust and highly accurate three-dimensional position indication.

[0059] With regard to the use of relatively fast and simple signal processing to provide a robust and highly accurate three-dimensional position indication, one consideration is the linearity of the position or displacement signal components (or the linearity of certain combined signals, such as the Z signal relationship shown in Equation 5). It should be understood that signals or signal relationships that vary with displacement due to significant third- and / or fifth-order signal variation contributions will generally require more complex signal processing and / or correction and / or calibration to provide an accurate displacement or position indication. The inventors have discovered that certain desirable configurations tend to suppress the contributions of higher-order signal variations in the axial signal components A and / or combinations thereof. As one way of describing these desirable configurations, the detector coils of the upper and lower axial detector coil arrangements TASCC and BASCC may be considered to define an "axial detector coil inscribed cylinder," defined to be concentric with the central axis CA and have the minimum necessary radius such that the upper and lower axial detector coils (e.g., the detector coils of the upper and lower axial detector coil arrangements TASCC and BASCC shown in FIG. 5) can fit inside them (i.e., the axial detector coil inscribed cylinder may be defined to be concentric with the central axis CA and have a radius that is the largest radius that can be inscribed within the edges of the upper and lower axial detector coils). A "disruptor inscribed cylinder" may be defined to be concentric with the central axis CA and have a radius that is the largest radius that can be inscribed within the edges of a disruptor element (e.g., disruptor element 551). In various embodiments, it is desirable (but not required) that the radius of the disruptor inscribed cylinder be at least 1.1 times the radius of the axial detector coil area inscribed cylinder. In some embodiments, it is desirable (but not essential) for the radius of the disruptor inscribed cylinder to be at least 1.2 or at least 1.5 times the radius of the axial detection coil region inscribed cylinder.

[0060] 7A-7E illustrate "planar" views (viewed along the axial or Z direction) depicting embodiments of "four complementary pairs" of stylus position detection unit components, respectively, including receive coil sections 770A-770E and disruptor elements 751A-751E, in accordance with the principles disclosed herein. The illustrated components are usable in various embodiments of stylus position detection units according to the principles disclosed herein. While field-generating coils are not shown in FIGS. 7A-7E, it will be understood that they are provided in accordance with the principles previously disclosed. The various components illustrated in FIGS. 7A-7E are the same or similar to like-numbered components in the previously described stylus position detection units 311, 411, 511, and / or 511′ and can generally be understood by analogy thereto. Accordingly, only certain unique or significant characteristics of the "four complementary pairs" embodiments included in FIGS. 7A-7E are described below.

[0061] Figure 7A illustrates, and can be understood by analogy with, an embodiment of a receive coil section 770A and a disruptor element 751A similar to those described above with reference to stylus position detection section 511'. In addition to illustrating circular upper and lower axial detection coil arrangements TASCC and BASCC similar to those described above with reference to stylus position detection section 511', Figure 7A also illustrates alternative square upper and lower axial detection coil arrangements TASCC' and BASCC', shown in dashed lines. More generally, it will be understood that any desired shape can be used for the upper and lower axial detection coil arrangements, so long as they are configured to provide the desired operation in accordance with the various principles disclosed and / or claimed herein.

[0062] Note that the shape of disruptor element 751A includes "trimmed corners" for compactness. To realize the principles previously disclosed herein, the magnitude of change in overlap areas TRSCOAi and BRSCOAi associated with a disruptor displacement increment is nominally the same for any of the illustrated complementary pairs, and therefore, the ranges of operational travel + / -Rx and + / -Ry along the orthogonal X and Y directions can be defined or specified to not exceed the straight edge portions that traverse each complementary pair to satisfy this principle.

[0063] 7B illustrates an embodiment of a receive coil section 770B and disruptor element 751B similar to that described above with reference to FIG. 7A, except that the complementary pair CP1-CP4 of receive coil section 770B includes a larger rotational detection coil that overlaps the detection coils of the upper and lower axial detection coil arrangements TASCC and BASCC. Note that including such a large rotational detection coil in the complementary pair CP1-CP4 is not prohibited in accordance with various principles disclosed herein. To fabricate such a configuration, the rotational and axial detection coils can be fabricated, for example, on respective layers of a multilayer printed circuit board.

[0064] 7C illustrates an embodiment of a receive coil section 770C and disruptor element 751C similar to that described above with reference to FIG. 7B, except that the upper and lower axial detector coil arrangements TASCC and BASCC are not provided by axial detector coils separate from the various rotating detector coils TRSCi and BRSCi. Instead, it will be appreciated that the upper axial detector coil arrangement TASCC comprises a combination of N (N=4) upper rotating detector coils TRSC1-TRSC4, and the upper axial detector overlap area TASOA comprises the sum of the individual overlap areas TRSCOAi associated with the N upper rotating detector coils. It will be observed that, due to the similar shapes of the N upper rotating detector coils TRSC1-TRSC4 and the two parallel pairs of disruptor elements overlapping them, all overlap area lost in overlap area TRSCOA1 due to a displacement increment of the disruptor element 751C is gained in overlap area TRSCOA2, and vice versa. Similarly, all overlap area lost in overlap area TRSCOA3 is gained in overlap area TRSCOA4, and vice versa. Thus, the sum of overlap areas TRSCOAi does not change with or depend on the position of the disruptor element 751C within the operational ranges of travel + / -Rz, + / -Rx, and + / -Ry, even though its constituent individual overlap areas TRSCOAi change depending on the position of the disruptor element 751C. Similarly, the lower axial detection coil configuration BASCC comprises a combination of N (N=4) lower rotation detection coils BRSC1-BRSC4, and the lower axial detection overlap area BASOA comprises the sum of the individual overlap areas BRSCOAi associated with the N lower rotation detection coils. The sum of the overlap areas BRSCOAi also does not vary with or depend on the position of the disruptor element 751C within the operating ranges of travel + / -Rz, + / -Rx, and + / -Ry, even though the constituent individual overlap areas BRSCOAi may vary depending on the position of the disruptor element 751C.7C provides a configuration in accordance with the general principles disclosed herein, in which receive coil section 770C and disruptor element 751C are configured to provide upper and lower axial-sensing overlap areas TASOA and BASOA, respectively, the amounts of overlap TASOA and BASOA not varying with or dependent on the position of the disruptor element within its operational ranges of motion + / -Rz, + / -Rx, and + / -Ry.

[0065] 7D shows an embodiment of a receive coil section 770D and disruptor element 751D that functions in a manner similar to that described above with reference to FIG. 7C, except that the axial detection coil arrangements TASCC and BASCC are not provided by axial detection coils that are separate from the various rotational detection coils TRSCi and BRSCi. Instead, the upper and lower axial detection coil arrangements TASCC and BASCC comprise respective combinations of N (N=4) upper and lower rotational detection coils TRSC1-TRSC4 and BRSC1-BRSC4. The upper axial detection overlap area TASOA comprises the sum of the individual overlap areas TRSCOAi associated with the N upper rotational detection coils, and the lower axial detection overlap area BASOA comprises the sum of the individual overlap areas BRSCOAi associated with the N lower rotational detection coils. Similar to the configuration shown in FIG. 7C , the sum of overlap areas TRSCOAi does not vary with or is independent of the position of the disruptor element 751D within the operational range of motion + / −Rz, + / −Rx, and + / −Ry, even though successive individual overlap areas TRSCOAi vary depending on the position of the disruptor element 751D. And the sum of overlap areas BRSCOAi does not vary with or is independent of the position of the disruptor element 751D within the operational range of motion + / −Rz, + / −Rx, and + / −Ry, even though successive individual overlap areas BRSCOAi vary depending on the position of the disruptor element 751D. Thus, despite its differences from the previously described configurations, the embodiment shown in FIG. 7D provides a configuration according to the general principles disclosed herein. The receive coil section 770D and disruptor elements 751D are configured to provide an upper axial-sensing overlap area TASOA and a lower axial-sensing overlap area BASOA. The respective amounts of overlap areas TASOA and BASOA do not vary with or depend on the position of the disruptor element within the operating travel ranges + / -Rz, + / -Rx, and + / -Ry.It will be understood that due to the illustrated shape of disruptor element 751D, to satisfy the principles disclosed earlier herein, the magnitude of change in overlap areas TRSCOAi and BRSCOAi associated with a disruptor displacement increment is nominally the same for any of the illustrated complementary pairs, and the ranges of operational movement + / -Rx and + / -Ry along the orthogonal X and Y directions are defined or specified such that none of the corners of disruptor element 751D move to their illustrated positions to such an extent that they cross the boundaries of the detection coils of any of the complementary pairs CP1-CP4.

[0066] FIG. 7E illustrates an embodiment of a receive coil section 770E and a disruptor element 751E similar to that described above with reference to FIG. 7A (or the stylus position detection section 511′), except that the upper and lower rotational detection coils of each complementary pair CPi are rotated relative to each other about the central axis by an angle 2*NAA. Note that NAA is the “non-alignment angle.” However, this embodiment becomes increasingly disadvantageous compared to the previously described configuration (in which the upper and lower rotational detection coils of each complementary pair CPi are aligned along the axial direction) as the non-alignment angle NAA increases. The reason for this disadvantage is that, because their overlapping regions with the disruptor element 751E are not “co-located,” the sum of the operating gaps between the disruptor element 751E and the upper and lower rotational detection coils of each complementary pair CPi (e.g., operating gap OG shown in FIG. 3) is not necessarily constant for all displacements of the disruptor element 751E. Therefore, their sum may not ideally be independent of the axial displacement ΔZ, as described above with reference to Equation 6. The configuration outlined above and shown in FIG. 7 is not prohibited in accordance with the various principles disclosed herein. It will be appreciated that such a configuration can still satisfy the most basic principles disclosed and claimed herein and provide signal components that at least partially retain the various advantages outlined above compared to known inductive sensor configurations. One way to describe the configuration shown in FIG. 7E is that the receive coil section 770E is configured so that each complementary pair CPi includes an upper rotating detector coil TRSCi and a lower rotating detector coil BRSCi whose internal region shapes are nominally identical when rotated about a central axis (e.g., by an angle 2*NAA) so that the shape of one of the complementary pair matches the angular position of the other about the central axis and projected along the axial direction (i.e., the shapes of the internal regions of the upper rotating detector coil TRSCi and the lower rotating detector coil BRSCi nominally match when rotated about the central axis so that the shape of one of the complementary pair matches at the angular position of the other about the central axis).In various embodiments, the receive coil section 770E and the disruptor element 751E may be configured such that the disruptor element 751E has at least N straight sides (e.g., N=4), and for any respective complementary pair CPi (e.g., CP1-CP4), each of the straight sides of the disruptor element 751E traverses both the upper rotation detection coil TRSCi and the lower rotation detection coil BRSCi of that respective complementary pair CPi. In such an embodiment where N=4, the at least N straight sides of the disruptor element 751E comprise four sides arranged parallel to the sides of a rectangle or square.

[0067] 8A-8F show "plan view" views (along the axial or Z direction) illustrating respective "three (or six) complementary pairs" of stylus position detection unit components comprising receive coil sections 870A-870F and disruptor elements 851A-851F, respectively, in accordance with the principles disclosed herein. The illustrated components are usable in various embodiments of stylus position detection units in accordance with the principles disclosed herein. While field-generating coils are not shown in FIGS. 8A-8F, it will be understood that they are provided in accordance with the principles previously disclosed. The various components shown in the "three (or six) complementary pairs" configurations illustrated in some of FIGS. 8A-8F are similar to, and can generally be understood by analogy with, corresponding components shown in the corresponding "four complementary pairs" configurations described above with reference to FIGS. 7A-7E. Accordingly, only certain unique or significant characteristics of the "three complementary pairs" embodiments included in FIGS. 8A-8F will be described below.

[0068] Figures 8A-8C are "three complementary pair" analogs of the "four complementary pair" constructs shown in corresponding Figures 7A-7C, and can generally be understood by analogy with the descriptions of their corresponding constructs (e.g., Figure 8A to its corresponding Figure 7A, etc.), based on the additional description below.

[0069] In contrast to the four previously described complementary pairs oriented 90 degrees from each other (e.g., as shown in FIG. 7A), the use of three complementary pairs oriented 120 degrees from each other can be understood by considering that any displacement increment or position of a disruptor element (e.g., 851A) is readily characterized by the displacement or position vector components or coordinates oriented along each of the vector component directions VC1, VC2, and VC3 shown in FIGS. 8A-8F, as opposed to the displacement or position vector components or coordinates oriented along the X-axis and Y-axis directions shown in the various figures herein. Methods for converting vector components from one coordinate system to another are well known and need not be described in detail here. Based on this, it will be appreciated that the complementary pairs CPi shown in FIGS. 8A-8C are constructed according to the same principles outlined in the preceding description of complementary pairs, with their respective overlapping regions indicating the displacement or position of the disruptor element along their corresponding vector component directions VC1, VC2, and VC3. For example, the representative overlap regions TRSCOA1 and BRSCOA1 shown in Figure 8A result in associated signal components SIGTRSC1 and SIGBRSC1 according to the principles previously described that indicate the displacement or position of the disruptor elements along the corresponding vector component direction VC1, etc. In the embodiments shown in Figures 8A, 8C, and 8E, in one embodiment, the rotational displacement or position component ΔVC1 along the VC1 direction can be indicated by or correspond to the following signal relationship, which is nominally independent of ΔZ according to the principles previously outlined for comparable complementary pairs: ΔVC1 = function [(SIGTRSC1+SIGBRSC1)-(SIGTRSC1 UNDF +SIGBRSC1 UNDF ] (Formula 8)

[0070] where SIGTRSC1 UNDF and SIGBRSC1 UNDF is the reference signal value resulting from the overlapping regions TRSCOA1 and BRSCOA1 corresponding to the undeflected position UNDF of the disruptor element (such as 851A).

[0071] Similarly, the rotational displacement or position component ΔVC2 along the VC2 direction and the rotational displacement or position component ΔVC3 along the ΔVC3 direction may be represented by or correspond to the following signal relationships: ΔVC2 = function [(SIGTRSC2 + SIGBRSC2) - (SIGTRSC2 UNDF +SIGBRSC2 UNDF ] (Formula 9) ΔVC3 = function [(SIGTRSC3 + SIGBRSC3) - (SIGTRSC3 UNDF +SIGBRSC3 UNDF ] (Formula 10)

[0072] It will be understood that the axial detection coil configurations TASCC and BASCC shown in Figures 8A-8C are substantially the same as those previously described herein with reference to corresponding configurations and can be determined according to the same types of signal components and signal relationships. The signal relationships outlined above are exemplary only and are not limiting. In various embodiments, these signal relationships may be adjusted or compensated for, as needed, by additional calibration or signal processing operations, including operations to reduce the effects of geometric and / or signal cross-coupling between various displacement directions or signal components.

[0073] FIG. 8D illustrates an embodiment of a receive coil section 870D and disruptor element 851D similar to that described above with reference to FIG. 8A, except that additional complementary pairs CP4-CP6 are provided, configured symmetrically across the central axis from complementary pairs CP1-CP3, to provide a total of six complementary pairs. In particular, CP1 and CP4 face opposite each other along the VC1 direction, CP2 and CP5 face opposite each other along the VC2 direction, and CP3 and CP6 face opposite each other along the VC3 direction. These opposing pairs are similar to the opposing complementary pairs shown along the X and Y axis directions in FIGS. 7A-7D. Such a configuration is useful for determining the reference signal values ​​(e.g., SIGTRSC1) used in Equations 8-10. UNDF8D , in one embodiment, the rotational displacement or position component ΔVC1 along the VC1 direction may be represented by or correspond to the following signal relationship: ΔVC1 = ΔV / √{square root over (V)} ... ΔVC1 = function [(SIGTRSC1+SIGBRSC1)-(SIGTRSC4+SIGBRSC4)]÷ [(SIGTRSC1+SIGBRSC1)+(SIGTRSC4+SI GBRSC4)] (Equation 11) ΔVC2 = function [(SIGTRSC2+SIGBRSC2)-(SIGTRSC5+SIGBRSC5)]÷ [(SIGTRSC2+SIGBRSC2)+(SIGTRSC5+SI GBRSC5)] (Equation 12) ΔVC3 = function [(SIGTRSC3+SIGBRSC3)-(SIGTRSC6+SIGBRSC6)]÷ [(SIGTRSC3+SIGBRSC3)+(SIGTRSC6+SI GBRSC6)] (Equation 13)

[0074] It will be appreciated that the "three complementary pairs" embodiment shown in Figures 8B and 8C can be similarly adapted to have six complementary pairs and use similar signal processing with similar advantages.

[0075] FIG. 8E illustrates an embodiment of a receive coil section 870E and disruptor element 851E similar to those described above with reference to FIG. 7E and will generally be understood by analogy with that description in conjunction with the preceding description of FIGS. 8A-8C. A simplified restatement of that description is that in FIG. 8E, the upper and lower rotating detector coils of each complementary pair CPi are rotated relative to one another about the central axis by an angle 2*NAA, where NAA is the "misalignment angle." This embodiment becomes increasingly disadvantageous compared to the configuration outlined above (in which the upper and lower rotating detector coils of each complementary pair CPi are axially aligned) as the misalignment angle NAA increases, as described above with reference to FIG. 7E. It is noted here that the sum of the signals from the complementary pairs may not ideally be independent of axial displacement ΔZ, as described above with reference to Equation 6. Nevertheless, such a configuration is not prohibited in accordance with the various principles disclosed herein. It will be appreciated that such an arrangement can provide signal components that still meet the most basic principles disclosed and claimed herein and retain, at least in part, the various advantages outlined above compared to known inductive sensor arrangements.

[0076] 8F illustrates an embodiment of a receive coil section 870F and a disruptor element 851F in which a complementary pair of detector coils CPi has detector coils configured differently from those of the previously described complementary pairs (e.g., shown in FIG. 8A) and is arranged symmetrically about a central axis. Thus, the receive coil section and disruptor element are characterized similarly to the previously described complementary pairs in that the receive coil section and disruptor element are further configured such that for a displacement increment of any complementary pair CPi and any disruptor element within the operational travel ranges + / -Rz, + / -Rx, and + / -Ry, the magnitude of the change in overlap areas TRSCOAi and BRSCOAi associated with the disruptor displacement increment is the same for that complementary pair. Furthermore, in the embodiment shown in FIG. 8F, the receive coil section is configured similarly to several complementary pairs previously described herein, with each complementary pair CPi comprising an upper rotating detection coil TRSCi and a lower rotating detection coil BRSCi that are rotated at an offset angle (e.g., 180 degrees) about the central axis so that the shape of one of them (i.e., the upper rotating detection coil TRSCi and the lower rotating detection coil BRSCi) matches the angular position of the other about the central axis, and characterized so that the shapes of their internal regions nominally match when projected along the axial direction.

[0077] However, in contrast to the previously described complementary pairs, the sign of the change in overlap area TRSCOAi and BRSCOAi relative to a disruptor displacement increment is opposite in the complementary pair shown in FIG. 8F. Such an embodiment may have certain disadvantages compared to embodiments in which the sign of the change in overlap area TRSCOAi and BRSCOAi relative to a disruptor displacement increment is the same for each complementary pair. However, the configuration shown in FIG. 8F is nevertheless not prohibited in accordance with various principles disclosed herein. With appropriate signal processing, such an embodiment can offer certain advantages for use in a scanning probe compared to known inductive sensing configurations. The signal processing may need to be more complex than required in previously disclosed embodiments herein (e.g., using more complex signal component relationships to represent various displacement or position vector components) to correct for or compensate for various cross-coupling effects, etc. However, for receive coil section 870F, such effects can generally be compensated for based on known geometric and / or signal relationship constraints and the fact that the magnitude of the change in overlap area for a given displacement of disruptor element 851F is the same for each complementary pair of sensing coils. 8F, disruptor element 851F has three pairs of parallel straight sides (e.g., arranged parallel to the sides of a regular hexagon), such that for any respective complementary pair CPi, the first of the pair of parallel straight sides intersects the upper rotating detection coil TRSCi and the second of that pair of parallel straight sides intersects the lower rotating detection coil BRSCi of its respective complementary pair. Based on the known rigid-body translation and rotation characteristics of disruptor element 851F, the respective overlap regions and local operating gaps of each detection coil are provided in receive coil section 870F such that they are constrained by known relationships to one another, and these known relationships can be used in signal processing of the signal components provided by receive coil section 870F to determine accurate displacement vectors.

[0078] It will be appreciated that the variations shown in Figures 7A-7E and 8A-8F retain many or all of the advantages previously discussed in connection with the various principles disclosed and claimed herein, while illustrating the possibility of further rearranging and / or adjusting the configuration and combination of the various components within the stylus position detection unit in accordance with these principles. In general, it should be understood that the various embodiments disclosed herein are for illustrative purposes only and not limiting.

[0079] Figures 9A and 9B show an alternative configuration of a stylus position detector 911. This stylus position detector may be used, for example, as stylus position detector 311 in scanning probe 300 of Figure 2, in place of stylus position detector 411 in the embodiment of Figure 3, in place of stylus position detector 511 in the embodiment of Figure 4, etc. Inductive components are shown in Figure 9B. The stylus position detector 911 uses inductive detection principles and comprises a coil substrate arrangement 990 having a receive coil section 970, a field generating coil arrangement 960 comprising a transmit coil (first field generating coil) 961 as shown, and a disruptor arrangement 950 comprising first and second disruptor elements 951 as shown. The receive coil section 970 may comprise a rotational detector coil section (also referred to as a rotational detector coil) RSC and an axial detector coil arrangement ASCC. Simply put, the moving disruptor element 951 (or, more generally, the disruptor arrangement 950) causes position-dependent variations in the varying magnetic field produced by the field-generating coil arrangement 960. The receive coil section 970 responds to the varying magnetic field caused by the disruptor element 951 and the variations therebetween.

[0080] The coil substrate assembly 990 includes a first substrate portion 992 including N upper rotary detector coil sections (upper rotary detector coils, TRSC1 to TRSC4 as shown, where N=4 in this example) and an upper axial detector coil assembly (TASCC as shown), and a second substrate portion 994 including N lower rotary detector coil sections (lower rotary detector coils, BRSC1 to BRSC4 as shown, where N=4 in this example) and a lower axial detector coil assembly (BASCC as shown). The coil substrate assembly 990 also includes a central substrate portion 996 disposed between the first substrate portion 992 and the second substrate portion 994. The central substrate portion 996 includes at least a first field-generating coil assembly 960 (including a transmit coil 961 as shown). The coil substrate arrangement 990 is mounted in fixed relationship to the frame of the scanning probe (see scanning probe 300 in FIG. 2 and frame 408 in FIG. 4), with a second substrate portion 994 of the coil substrate arrangement 990 closer to the stylus suspension 307 / 407 (see FIGS. 2 and 3). The first substrate portion 992, second substrate portion 994 and central substrate portion 996 of the coil substrate arrangement 990 are nominally parallel to one another and nominally perpendicular to the central axis CA (see FIG. 3) of the scanning probe 300 (see FIG. 2). The coil substrate arrangement 990 may comprise, for example, a double-sided board or printed circuit board having a coil fabricated as a printed conductor on a layer of the board or printed circuit board, a free-standing coil fixed to a board or printed circuit board, etc., and / or various combinations thereof.

[0081] In various embodiments, the disruptor elements 951 of the disruptor arrangement 950 each comprise at least one of a conductive plate or a conductive loop that provides a disruptor area, and the disruptor elements 951 are arranged along a central axis CA (see FIG. 3) in a disruptor movement volume that extends on opposite sides of the coil substrate arrangement 990. The disruptor element 951 comprises an upper portion of the moving member 912 (e.g., similar to the moving member 412 of FIG. 3) and is coupled to the stylus suspension 307 / 407 (see FIGS. 2 and 3) in a fixed relationship relative to each other by a coupling arrangement 953. The disruptor element 951 moves within the disruptor movement volume relative to an undeflected position in response to deflection of the stylus suspension 307 / 407 (see Figures 2 and 3), with the disruptor element moving through an axial range of motion + / -Rz in response to axial motion and respective orthogonal X and Y directions orthogonal to the axial direction, + / -Rx and + / -Ry. The projection of the coil area of ​​the first field-generating coil 961 along the axial direction encompasses conductive plates or loops that provide the disruptor and coil areas of all rotational and axial detection coils disposed on the coil substrate arrangement 990. The field-generating coil arrangement 960 generates a varying magnetic flux generally along the axial direction within the disruptor movement volume in response to a coil drive signal.

[0082] Figure 10 is a partial schematic isometric view of an embodiment of a stylus position detector 1011 similar to the stylus position detector 911 shown in Figures 9A and 9B, highlighting certain features in accordance with principles disclosed herein. It will be understood that, in general, the stylus position detector 1011 includes certain components similar to those of the stylus position detectors 311, 411, 511, and 911 of Figures 2, 3, 4, 9A, and 9B, and operates similarly except as noted below. The stylus position detector 1011 configuration may be used, for example, as the stylus position detector 311 in the scanning probe 300 of Figure 2, in place of the stylus position detector 411 in the embodiment of Figure 3, in place of the stylus position detector 511 in the embodiment of Figure 4, in place of the stylus position detector 911 in the embodiment of Figures 9A and 9B, etc.

[0083] 10, the stylus position detection portion 1011 includes a coil substrate assembly 1090 and a disruptor assembly 1050. The coil substrate assembly 1090 includes a field-generating coil substrate portion 1060 disposed between an upper receive coil substrate portion 1070T and a lower receive coil substrate portion 1070B, comprising upper and lower receive coil substrate portions 1070T, 1070B. In various embodiments, the upper and lower receive coil substrate portions 1070T, 1070B are also referred to as first and second substrate portions 1070T, 1070B, and the field-generating coil substrate portion 1060 is also referred to as a central substrate portion 1060. The disruptor assembly 1050 includes disruptor elements 1051T, 1051B or a scale. In various embodiments, the disruptor elements 1051T, 1051B are also referred to as first and second disruptor elements 1051T, 1051B.

[0084] In various embodiments, the disruptor elements 1051T, 1051B (or more generally the disruptor structure 1050) may each comprise at least one of a conductive plate or loop that provides a disruptor area (e.g., an interior area thereof), or parallel conductive plates or loops (e.g., as provided on two sides of a printed circuit board patterned by printed circuit board manufacturing techniques), or any other desired operating structure. As shown in FIG. 10 , the disruptor elements 1051T and 1051B each comprise a conductive plate. The disruptor elements 1051T and 1051B are positioned along a central axis CA of the disruptor moving volume MV that extends on opposite sides of the coil substrate structure 1090 and are coupled to the stylus suspension 1007 by a coupling structure (e.g., comprising at least an upper portion of the moving member 1012 similar to the moving member 412 of FIG. 3 ). For purposes of explanation, the disruptor elements 1051T, 1051B move relative to an undeflected position shown in Figure 10 (e.g., similar to the undeflected position UNDF of Figure 3) in response to deflection of the stylus suspension 1007 and / or stylus 1006 and / or moving member 1012 (which may, for example, be similar to or identical to the stylus suspension 407, stylus 406 and moving member 412 of Figure 3). The disruptor elements 1051T, 1051B can be described as moving along the axial direction in displacement increments ΔZ over an operational range of travel + / -Rz in response to axial movement, and along orthogonal X and Y directions orthogonal to the axial direction (Z direction) in displacement increments ΔX and ΔY, respectively, over respective operational ranges of travel + / -Rx and + / -Ry in response to rotational movement.

[0085] The upper receiver coil substrate section 1070T includes N upper rotating detector coils TRSC (e.g., TRSC1 to TRSC4 as shown, N=4) and an upper axial detector coil arrangement TASCC (e.g., comprising a single illustrated individual coil in this embodiment), and the lower receiver coil substrate section 1070B includes N lower rotating detector coils BRSC (e.g., BRSC1 to BRSC4 as shown, N=4) and a lower axial detector coil arrangement BASCC (e.g., comprising a single illustrated individual coil in this embodiment).

[0086] The coil substrate arrangement 1090 is mounted in fixed relation to the frame of the scanning probe (e.g., frame 408 of FIG. 4 ) at the lower receive coil substrate portion 1070B, which is closer to the stylus 1006 and / or stylus suspension 1007. With respect to the various detector coils shown in FIG. 10 , it will be understood that all coils comprise at least one winding or conductor having first and second connection ends (e.g., as shown in FIG. 6 ) configured to operate with one or more turns inductively coupled. As shown, the upper and lower axial detector coil arrangements TASCC and BASCC, and the upper and lower rotational detector coil arrangements TRSC and BRSC, are spaced nominally symmetrically with respect to the location of the disruptor arrangement 1050 and corresponding disruptor elements 1051T, 1051B. Other configurations are possible (e.g., in some embodiments, the rotational detector coil arrangements TRSC and BRSC may not be nominally centered with respect to the disruptor arrangement 1050).

[0087] The field-generating coil substrate section 1060 generally comprises at least a first field-generating coil 1061 and is disposed between the upper receive coil substrate section 1070T and the lower receive coil substrate section 1070B. As shown in Figure 10, the at least first field-generating coil comprises a single field-generating coil 1061 having an area larger than the areas of the disruptor elements 1051T, 1051B. The upper receive coil substrate section 1070T, the field-generating coil substrate section 1060, and the lower receive coil substrate section 1070B are nominally planar, nominally parallel to one another, and nominally orthogonal to the central axis CA.

[0088] In the embodiments illustrated in FIGS. 3, 4, and 5, the disruptor elements are positioned inside the field-generating coil elements (e.g., disruptor element 551 in FIG. 4 fits inside field-generating coil 561), and the area of ​​the disruptor elements is smaller than the area of ​​the field-generating coil elements. In the illustrated embodiments of FIGS. 9A, 9B, and 10, the disruptor elements are positioned parallel to the field-generating coil elements (e.g., disruptor elements 1051T, 1051B are positioned above and below field-generating coil 1061). The configurations of FIGS. 9A, 9B, and 10 provide increased flexibility regarding the relative sizes of the disruptor elements and field-generating coil elements. Additionally, utilizing a single printed circuit board (e.g., where the first substrate portion, second substrate portion, and center substrate portion may comprise portions of a single multilayer printed circuit board) can reduce cost and complexity relative to configurations utilizing multiple printed circuit boards.

[0089] Figure 11 is a partial schematic isometric view of an alternative embodiment of a stylus position detector 1111 similar to the stylus position detector 1011 shown in Figure 10, highlighting certain features in accordance with principles disclosed herein. It will be understood that, in general, the stylus position detector 1111 comprises certain components similar to those of the stylus position detector 1011 of Figure 10 and operates similarly, except as otherwise described below. The stylus position detector 1111 configuration may be used, for example, as stylus position detector 311 in scanning probe 300 of Figure 2, in place of stylus position detector 411 in the embodiment of Figure 3, in place of stylus position detector 511 in the embodiment of Figure 4, in place of stylus position detector 911 in the embodiment of Figures 9A and 9B, in place of stylus position detector 1011 in the embodiment of Figure 10, etc.

[0090] 11 , the stylus position detection portion 1111 includes a coil substrate assembly 1190 and a disruptor assembly 1150. The coil substrate assembly 1190 includes a field-generating coil substrate section 1160 disposed between an upper receive coil substrate section 1170T and a lower receive coil substrate section 1170B, comprising upper and lower receive coil substrate sections 1170T, 1170B. In various embodiments, the upper and lower receive coil substrate sections 1170T, 1170B are also referred to as first and second substrate sections 1170T, 1170B, and the field-generating coil substrate section 1160 is also referred to as a central substrate section 1160. The disruptor assembly 1150 includes disruptor elements 1151T, 1151B or scales. In various embodiments, the disruptor elements 1151T, 1151B are referred to as first and second disruptor elements 1151T, 1151B. The illustrated upper and lower receive coil substrate sections 1170T, 1170B are generally similar to the corresponding upper and lower receive coil substrate sections 1070T, 1070B of Figure 10 (details of the conductive vias and pads are shown in Figure 11).

[0091] In various embodiments, the disruptor elements 1151T, 1151B (or, more generally, the disruptor structures 1150) can each comprise at least one of a conductive plate or a conductive loop, or parallel conductive plates or loops (e.g., as provided on two sides of a printed circuit board patterned by printed circuit board manufacturing techniques), or any other desired operating structure that provides a disruptor area (e.g., an interior area thereof). In various embodiments, the structures comprising conductive loops can comprise at least one of concentric loops, spiral patterns, etc. As shown in FIG. 11, the disruptor elements 1151T and 1151B each comprise a plurality of concentric conductive loops 1153 instead of the conductive plates used in the embodiment illustrated in FIG. 10. The disruptor elements 1151T and 1151B extend on opposite sides of the coil substrate arrangement 1190 and are positioned along a central axis CA of the disruptor movement volume MV which is coupled to the stylus suspension in a manner similar to that described above with reference to Figure 10 (see stylus suspension 1007 in Figure 10).

[0092] The field-generating coil substrate section 1160 typically includes at least a first field-generating coil. As shown, the field-generating coil substrate section 1160 includes an upper field-generating coil section 1161T and a lower field-generating coil section 1161B, and is disposed between an upper receive coil substrate section 1170T and a lower receive coil substrate section 1170B. The upper receive coil substrate section 1170T, the field-generating coil substrate section 1160, and the lower receive coil substrate section 1170B are nominally planar, nominally parallel to one another, and nominally perpendicular to the central axis CA. In the embodiment of FIG. 11, the field-generating coil substrate section 1160 includes a two-turn multi-turn field-generating coil. and two corresponding field generating coil sections 1161T and 1161B connected by a via and positioned approximately equidistant from the mid-plane of the disruptor movement volume MV along the central axis and nominally perpendicular to the central axis in the plane (i.e., the field generating coil arrangement comprises a multi-turn field generating coil with at least two turns and two corresponding field generating coil sections 1161T and 1161B positioned approximately equidistant from the mid-plane of the disruptor movement volume MV along the central axis CA and nominally perpendicular to the central axis CA in the plane).

[0093] As shown in FIG. 11 , the upper and lower field generating coil sections 1161T and 1161B have areas smaller than the areas of the disruptor elements 1151T, 1151B. Using field generating coils having areas smaller than the areas of the disruptor elements facilitates reducing the sensitivity of the stylus position detection section 1111 to the size of the disruptor elements or scale. The use of conductive loops (e.g., concentric loops, spiral patterns, etc.) in the disruptor elements, instead of conductive plates or single conductive loops, also facilitates reducing the sensitivity of the stylus position detection section 1111 to the size of the disruptor elements or scale while maintaining good X and Y position signal strength. Reducing the sensitivity of the stylus section to the size of the disruptor elements or scale can improve measurement accuracy and reduce processing costs associated with producing results in a desired output format.

[0094] In some embodiments, due to the proximity of the receive coils (e.g., rotational detection coils BRSC1-BRSC4, TRSC1-TRSC4) to the transmitters (e.g., field-generating coil sections 1161T, 1161B), unconnected vias / pads may be added to balance offsets otherwise produced by connecting traces (such as transmitter and receiver leads) or other components. As an illustrative example, in the embodiment of FIG. 11 , certain connecting vias / pads / leads (e.g., as connected to electronic circuits or configurations and / or portions thereof) are shown in the rotational detection coil BRSC3 / TRSC3 (e.g., for connecting traces) that do not have symmetrically connected counterparts (e.g., symmetric about a central axis) in the symmetric rotational detection coil BRSC4 / TRSC4 (e.g., five such vias, as well as top and bottom transmit leads, are shown in the rotational detection coil BRSC3 / TRSC3 of the example configuration of FIG. 11 , as well as three vias for connections for axial detection coil configurations TASCC, BASCC, and normalization coil R N (These include vias for connecting the field-generating coil sections 1161T, 1161B, vias for connecting the field-generating coil sections 1161T, 1161B, and upper and lower transmit leads for the field-generating coil sections 1161T, 1161B. In some embodiments, such traces / vias / pads / leads can reduce magnetic fields into the receive coils that, if uncompensated, result in signal offsets. In some embodiments, such offsets can be addressed by mirroring such features (e.g., on opposite sides of the central axis) in a symmetric receive coil with unconnected vias / pads / leads. For example, in one embodiment, unconnected vias / pads / leads can be added in the rotational detection coil BRSC4 / TRSC4, and each of the rotational detection coils BRSC4 / TRSC4 can mirror / symmetrically represent the corresponding connecting vias / pads / leads in the rotational detection coil BRSC3 / TRSC3 (e.g., five unconnected vias and top and bottom pads can be added in the rotational detection coil BRSC4 / TRSC4, and each of the rotational detection coils BRSC4 / TRSC4 can mirror / symmetrically represent the corresponding connecting vias / pads / leads shown in the rotational detection coil BRSC3 / TRSC3).

[0095] As a specific illustrative example of such a concept, in FIG. 11, a normalized coil R N The connection of the part A connecting component (e.g., a via) is shown electrically connected through VIA1C and is shown in the rotational detection coil BRSC3 / TRSC3. In accordance with the principles described above, an unconnected via VIA1D can be included in the rotational detection coil BRSC4 / TRSC4 that mirrors / symmetrically (e.g., mirrors and symmetrically about the central axis of the structure) the corresponding connecting via VIA1C shown in the rotational detection coil BRSC3 / TRSC3. More specifically, the via VIA1D is at a position in the rotational detection coil BRSC4 / TRSC4 that is symmetrically / mirroring the position of the via VIA1C in the rotational detection coil BRSC3 / TRSC3 (e.g., such that a line between the position of the via VIA1C and the position of the via VIA1D passes through the central axis of the structure, and each position is equidistant from the central axis). The via VIA1D thereby balances the offset created by the via VIA1C as described above. More specifically, the unconnected component VIA1D is disposed within the rotation detection coil BRSC4 / TRSC4 (first rotation detection coil) and is symmetrically opposite (i.e., axially opposite) the similar electronically connected component VIA1C disposed within the rotation detection coil BRSC3 / TRSC3 (second rotation detection coil), and the unconnected component VIA1D thereby reduces a signal offset that occurs in the signal components provided by the rotation detection coils BRSC3 / TRSC3 and BRSC4 / TRSC4 due to the presence of the connected component VIA1C within the rotation detection coil BRSC3 / TRSC3.

[0096] In the embodiment of FIG. 11, the normalization coil R N The via for connecting the part VIA1C is axial Shown in close proximity to the connection vias for the detection coil structures TASCC and BASCC. Normalization coil R Nhas an upper portion and a lower portion, the upper portion extending radially in a straight line and connected by a via VIA1C to the lower portion, which also extends radially in a straight line. (The lower portion is not shown in FIG. 11 because it is obscured by other components for simplicity, but is located directly below the upper portion.) In various embodiments, the normalization coil R N is used to provide a measure of the transmit field (i.e., normalized coil R) (e.g., corresponding to the varying magnetic flux generated by the field generating coil arrangement (also called field generating coil substrate) 1160). N is utilized to provide a measurement of the varying magnetic flux generated by the field-generating coil arrangement 1160), where the measured signal is relatively independent of the position of the disruptor elements 1151T, 1151B (e.g., may be only nominally affected by the position of the disruptor elements 1151T, 1151B). In various embodiments, the position measurement may be made relatively insensitive to variations in transmit amplitude (from the field-generating coil arrangement 1160) in this measured signal. In various embodiments, such processing may be performed by signal processing and control circuitry (e.g., signal processing and control circuitry 380 of FIG. 2).

[0097] 9A, 9B, 10 and 11, in a manner similar to that described above with reference to Figures 2-8F, the rotational detection coil sections RSC (as shown in TRSC1-TRSC4 and BRSC1-BRSC4) output at least first and second rotational signal components RSigs indicative of the rotational position (such as X and Y position signals) of the stylus coupling section 342 (see Figure 2) on corresponding signal lines, and the axial detection coil arrangement ASCC (as shown in TASCC and BASCC) outputs one or more axial signal components ASigs indicative of the axial position (e.g., Z position signal) of the stylus coupling on corresponding signal lines. In various embodiments, the signal processing and control circuitry 380 (see Figure 2) receives the rotational signal components RSigs and the axial signal components ASigs and can perform various levels of associated signal processing in various embodiments. For example, in one embodiment, signal processing and control circuits combine and / or process signal components from the various receive coils in various relationships and provide the resulting rotational and axial position signal outputs RPSOut and APSOut in the desired output format via mount 224 (see FIG. 2). Referring to FIG. 2, one or more receive units (e.g., in CMM 200, motion controller 115, host computer 120, etc.) can receive the rotational and axial position signal outputs RPSOut and APSOut, and one or more associated processing and control units can be utilized to determine the three-dimensional position of the stylus coupling unit 342 and / or the contact portion of the attached stylus 306 as its contact portion 348 moves along the surface of the workpiece W being measured. The number, size, and shape of the receive coils, field-generating coils, and conductive plates or loops of the disruptor element used in various embodiments can be selected based on desired operating characteristics, such as improved position detection and reduced higher-order nonlinearities. Note that lower-order nonlinearities can be calibrated out by the CMM.

[0098] 9A, 9B, 10, and 11 facilitate the use of fewer mechanical parts because in some embodiments only one board is required for mounting (e.g., no flexible cables between separate boards are required). Such embodiments also facilitate improved repeatability and reduced assembly costs due to fewer degrees of freedom for alignment of the receive coil, and may be less sensitive to tilt and rotation issues that can occur in multi-board embodiments, e.g., with respect to XY positioning signals.

[0099] Figures 12A and 12B show an alternative arrangement of a stylus position detector 1211 which may be employed in the scanning probe 300 of Figure 2 as, for example, stylus position detector 311, such as in place of stylus position detector 511 in the embodiment of Figure 4 or in place of stylus position detector 411 in the embodiment of Figure 3. The stylus position detector 1211 uses an inductive detection principle and comprises a disruptor arrangement 1250 and a coil substrate arrangement 1290. The disruptor arrangement 1250 as shown comprises a generally cylindrical disruptor (cylindrical disruptor element) 1251. The illustrated coil substrate arrangement 1290 has a generally disc-shaped arrangement and is shown in more detail in Figure 12B.

[0100] As shown, the disruptor (cylindrical disruptor element) 1251 is positioned within a central opening (hole) 1291 of the coil substrate structure 1290 and extends in the Z direction of the disk-shaped coil substrate structure 1290. While the example of FIGS. 12A and 12B shows the disruptor 1251 extending in the Z direction above and below the coil substrate structure 1290, it will be understood that this is not necessarily the case in other embodiments (e.g., in various alternative embodiments, the disruptor 1251 may be the same length as or shorter than the coil substrate structure 1290 in the Z direction). In various embodiments, it is the cylindrical shape of the disruptor 1251, rather than its height along the Z direction, that is the more significant factor (which results in various desirable operating characteristics, as described in more detail below, e.g., with respect to FIGS. 14A-14D ).

[0101] As shown, coil substrate structure 1290 includes a field-generating coil structure 1260 having two transmit coils (field-generating coils) 1261T and 1261B and a receive coil section 1270. Receive coil section 1270 may include a rotational detector coil section (also referred to as a rotational detector coil) RSC (for a detection operation transverse to the axial direction, e.g., as described above with reference to Figures 3-6, etc.) and an axial detector coil structure ASCC (for a detection operation along the axial direction, e.g., as described above with reference to Figures 3-6, etc.).

[0102] Briefly, the moving disruptor element 1251 (or more generally, the disruptor arrangement 1250) causes position-dependent variations in the changing magnetic field produced by the field-generating coil arrangement 1260. The receive coil section 1270 responds to the changing magnetic field and the variations therein caused by the disruptor element 1251.

[0103] As shown, coil substrate assembly 1290 includes a first substrate portion 1292 having upper axial detection coil TASCC and field generating coil 1261T, a second substrate portion 1294 having lower axial detection coil BASCC and field generating coil 1261B, and a central substrate portion 1296 disposed between first substrate portion 1292 and second substrate portion 1294. Central substrate portion 1296 includes upper rotational detection coils TRSC1-TRSC4 and upper normalization coil TR N and the lower normalization coil BR N and lower rotation detection coils BRSC1 to BRSC4.

[0104] The coil substrate structure 1290 is mounted in fixed relationship to the frame of the scanning probe (see scanning probe 300 in FIG. 2 and frame 408 in FIG. 4), with a second substrate portion 1294 of the coil substrate structure 1290 closer to the stylus suspension portion 307 / 407 (see FIGS. 2 and 3). The first substrate portion 1292, second substrate portion 1294 and central substrate portion 1296 of the coil substrate structure 1290 are nominally parallel to one another and nominally orthogonal to the central axis CA (see FIG. 3) of the scanning probe 300 (see FIG. 2). The coil substrate structure 1290 may comprise, for example, a double-sided board or printed circuit board with a coil fabricated by printing conductors into the layers of the board or printed circuit board, a free-standing coil connected to a board or printed circuit board, and / or various combinations thereof.

[0105] In various embodiments, the disruptor element 1251 of the disruptor structure 1250 is a conductive cylinder that provides the disruptor area. BecauseThe disruptor element 1251 may be disposed within a disruptor movement volume extending along a central axis CA (see FIG. 3) on either side of the coil substrate structure 1290. The disruptor element 1251 is coupled to the stylus suspension 307 / 407 (see FIGS. 2 and 3) in a fixed relationship to each other by a coupling structure 1253 that includes an upper portion of the moving member 1212 (e.g., similar to moving member 412 of FIG. 3). The disruptor element 1251 moves the disruptor movement volume relative to an undeflected position in response to deflection of the stylus suspension 307 / 407 (see FIGS. 2 and 3). The disruptor element 1251 moves within the disruptor movement volume, with the disruptor element 1251 moving axially through an operational range of movement + / -Rz in response to axial movement and moving along orthogonal X and Y directions orthogonal to the axial direction through respective operational ranges of movement + / -Rx and + / -Ry in response to rotational movement. The field-generating coil arrangement 1260 generates a varying magnetic flux generally along the axial direction within the disruptor movement volume in response to coil drive signals.

[0106] As discussed above with respect to FIG. 11, in various embodiments, the upper normalization coil TR N and the lower normalization coil BR N may be utilized to provide a measurement of the transmit field (e.g., corresponding to the varying magnetic flux generated by the field-generating coil arrangement 1260), such that the measured signal may be relatively independent of (e.g., only nominally affected by) the position of the disruptor element 1251. In various embodiments, the position measurement may be scaled to this measured signal to make it relatively insensitive to variations in transmit amplitude (from the field-generating coil arrangement 1260). In various embodiments, such processing may be performed by signal processing and control circuitry (e.g., signal processing and control circuitry 380 of FIG. 2).

[0107] 13A-13F show an embodiment of a stylus position detector 1311 similar to the stylus position detector 1211 shown in FIGS. 12A and 12B, highlighting particular features in accordance with the principles disclosed herein.

[0108] Figure 13A is a partial schematic isometric view of an embodiment of a stylus position detector 1311 similar to the stylus position detector 1211 shown in Figures 12A and 12B. It will be understood that, in general, the stylus position detector 1311 comprises certain components that are similar to the components of the stylus position detectors 311, 411, 511, and 911 of Figures 2, 3, 4, 9A, and 9B, and operate similarly except as otherwise described below. The stylus position detector 1311 configuration may be used, for example, as the stylus position detector 311 in the scanning probe 300 of Figure 2, in place of the stylus position detector 411 in the embodiment of Figure 3, in place of the stylus position detector 511 in the embodiment of Figure 4, in place of the stylus position detector 911 in the embodiment of Figures 9A and 9B, in place of the stylus position detector 1211 in the embodiment of Figures 12A and 12B, etc.

[0109] In the embodiment shown in Figure 13A, the stylus position detection portion 1311 comprises a coil substrate structure 1390 and a disruptor structure 1350. In various embodiments, the disruptor element 1351 (or more generally the disruptor structure 1350) comprises a conductive cylinder or other desired operating structure that provides a disruptor region (e.g., an interior region thereof). As illustrated in Figure 13A, the disruptor element 1351 comprises a conductive cylinder Consists ofThe disruptor element 1351 is disposed along a central axis CA of the disruptor moving volume MV that extends opposite the coil substrate arrangement 1390 and is coupled to the stylus suspension by a coupling arrangement (e.g., including at least an upper portion of the moving member 1312, similar to moving member 412 of FIG. 3). For purposes of explanation, the disruptor element 1351 moves relative to an undeflected position shown in FIG. 13A (e.g., similar to the undeflected position UNDF of FIG. 3) in response to deflection of the stylus suspension 1307 and / or the stylus 1306 and / or the moving member 1312 (which may be similar to or identical to the stylus suspension 407, stylus 406 and moving member 412 of FIG. 3). The disruptor element 1351 may be described as moving in response to axial movement along the axial direction through an operational range of movement + / -Rz in displacement increments ΔZ, and in response to rotational movement through an operational range of movement + / -Rx and + / -Ry along orthogonal X and Y directions orthogonal to the axial direction (Z direction) in respective displacement increments ΔX and ΔY.

[0110] The coil substrate arrangement 1390 comprises an upper coil substrate section 1390T and a lower coil substrate section 1390B. The upper coil substrate section 1390T includes an upper axial detection coil arrangement TASCC (e.g., consisting of a single illustrated individual coil in this embodiment), at least a first upper field-generating coil arrangement 1361T, N upper rotational detection coils TRSC (e.g., TRSC1-TRSC4 as illustrated, where N=4), and an upper normalization coil arrangement (upper normalization coil) TR N The lower coil substrate part 1390B includes a lower normalizing coil structure (lower normalizing coil) BR N , N lower rotating detection coils BRSC (e.g., BRSC1 to BRSC4 as shown, where N=4), at least a first lower field generating coil arrangement 1361B, and a lower axial detection coil arrangement BASCC (e.g., consisting of a single illustrated individual coil in this embodiment).

[0111] The coil substrate arrangement 1390 is mounted in fixed relation to the frame of the scanning probe (e.g., frame 408 of FIG. 4 ) at a lower coil substrate portion 1390B that is closer to the stylus 1306 and / or stylus suspension 1307. With respect to the various detector coils shown in FIG. 13A , it will be understood that all coils comprise at least one winding or conductor having first and second connection ends (e.g., as depicted in FIG. 6 ) configured to operate as one or more inductively coupled “turns.” As shown, the upper and lower axial detector coil arrangements TASCC and BASCC, as well as the upper and lower rotational detector coil arrangements TRSC and BRSC, are nominally symmetrically spaced relative to corresponding positions of the disruptor arrangement 1350 and disruptor element 1351. Other configurations are possible (eg, in some embodiments, the rotating detection coil arrangements TRSC and BRSC may not be nominally centered with respect to the disruptor arrangement 1350).

[0112] 13A, at least a first upper field-generating coil arrangement comprises a single upper field-generating coil (upper field-generating coil arrangement) 1361T having an area larger than the area of ​​the disruptor element 1351, and at least a first lower field-generating coil arrangement comprises a single lower field-generating coil (lower field-generating coil arrangement) 1361B having an area larger than the area of ​​the disruptor element 1351. The upper coil substrate portion 1390T and the lower coil substrate portion 1390B are nominally planar, nominally parallel to each other, and nominally perpendicular to the central axis CA.

[0113] Figures 13B-13E show an exemplary embodiment of the coil of the coil substrate construction 1390 of Figure 13A. Figure 13F shows an exemplary stackup of the coil of the coil substrate construction 1390 of Figure 13A. Figures 13A-13E show connection pads or vias (see Figure 13B) that may be similar to the connection pads or vias as described above in the description of Figure 11.

[0114] 13B, an exemplary embodiment of an upper axial detector coil arrangement TASCC or a lower axial detector coil arrangement BASCC is shown. As shown, a single coil is employed as the upper axial detector coil arrangement TASCC and a single coil is employed as the lower axial detector coil arrangement BASCC.

[0115] 13C, an exemplary embodiment of an upper field-generating coil arrangement 1361T or a lower field-generating coil arrangement 1361B is shown. As shown, a single coil is employed as the upper field-generating coil arrangement 1361T and a single coil is employed as the lower field-generating coil arrangement 1361B.

[0116] 13D shows an exemplary embodiment of the upper rotary detector coil arrangement TRSC or the lower rotary detector coil arrangement BRSC. As shown, four coils TRSC1 to TRSC4 are employed as the upper rotary detector coil arrangement TRSC, and four coils BRSC1 to BRSC4 are employed as the lower rotary detector coil arrangement BRSC.

[0117] In FIG. 13E, the upper normalized coil structure TR N or the lower normalization coil structure BR N As shown, a single coil is positioned in the upper normalized coil configuration TR N A single coil is employed as the lower normalized coil configuration BR N It is adopted as.

[0118] 13F shows an exemplary embodiment of layers of a coil substrate construction 1390. As described above with reference to FIG. 13A, the coil substrate construction 1390 comprises an upper coil substrate section 1390T and a lower coil substrate section 1390B. The upper coil substrate section 1390T, in turn, comprises a first layer having an upper axial detection coil construction TASCC, a second layer having at least a first upper field-generating coil construction 1361T, a third layer having N upper rotational detection coils TRSC, and an upper normalization coil construction TR NThe lower coil substrate section 1390B is generally a mirror image of the upper coil substrate section 1390T and includes a lower normalized coil configuration BR N a second layer having N lower rotary detection coils BRSC, a third layer having at least a first lower field generating coil arrangement 1361B, and a fourth layer having a lower axial detection coil arrangement BASCC. The disruptor element 1351 as shown is a conductive cylinder extending above and below the coil substrate arrangement 1390.

[0119] As noted above, in the embodiments shown in Figures 3, 4, and 5, the disruptor elements are positioned inside the field-generating coil elements (e.g., disruptor element 551 of Figure 4 fits inside field-generating coil 561), with the area of ​​the disruptor elements being smaller than the area of ​​the field-generating coil elements. In the embodiments shown in Figures 9A, 9B, and 10, the disruptor elements are positioned parallel to the field-generating coil elements (e.g., disruptor elements 1051T, 1051B are positioned above and below field-generating coil 1061). In the embodiments shown in Figures 12A, 12B, and 13A-13F, a single, tall, cylindrical disruptor element 1251 / 1351 fits within a hole 1291 surrounded by the coil elements, thereby providing increased flexibility in the configuration of the coil assembly substrate elements relative to their sizes and positions. On the other hand, utilizing a single printed circuit board (e.g., the top and bottom substrate portions may comprise portions of a single multilayer printed circuit board) may reduce cost and complexity relative to configurations utilizing multilayer printed circuit boards. Furthermore, as discussed in more detail below with respect to Figures 14A-14D, the embodiments of Figures 12A, 12B, and 13A-13F may provide a significant reduction in resonant frequency change (RFC) resulting from displacement along the Z-axis, as well as reduced off-axis crosstalk, resulting in improved overall performance of the CMM.

[0120] Because some embodiments require only one substrate to be attached (e.g., separate inter-substrate flexible cables may not be necessary) and can use a single-height disruptor element that does not need to be disassembled to attach or remove the substrate, the embodiments of FIGS. 12A, 12B, and 13A-13F can facilitate the use of fewer mechanical components. Such embodiments also facilitate improved repeatability and lower assembly costs because the receive coils may have fewer degrees of freedom for alignment. Therefore, such embodiments may be less sensitive to tilt and rotation issues that can arise in multi-substrate embodiments, for example, with respect to XY positioning signals. Such embodiments may also improve off-axis crosstalk, frequency stability, and linearity.

[0121] 14A-14C show exemplary frequency shifts and off-axis crosstalk errors for the embodiments shown in FIGS. 3, 4, and 5, the embodiments shown in FIGS. 9A, 9B, and 10, and the embodiments shown in FIGS. 12A, 12B, and 13A-13F. FIG. 14A shows exemplary off-axis crosstalk errors for the embodiments shown in FIGS. 3, 4, and 5 when the displacement of a disruptor (e.g., disruptor element 551 in FIG. 4) along the Z axis is swept from −1 mm to +1 mm and U, V=1.1 degrees. FIG. 14B shows exemplary off-axis crosstalk errors for the embodiments shown in FIGS. 9A, 9B, and 10 when the displacement of a disruptor (e.g., disruptor element 951 in FIG. 9A) along the Z axis is swept from −1 mm to +1 mm and U, V=1.1 degrees. FIG. 14C shows exemplary off-axis crosstalk errors for the embodiments shown in FIGS. 12A, 12B, and 13A-13F when the displacement of a disruptor (e.g., disruptor structure 1250 of FIG. 12A) along the Z axis is swept from -1 mm to +1 mm and U, V = 1.1 degrees. In each of FIGS. 14A-14C, the V-shaped Z signal is the primary (linear) positioning signal, and the X and Y signals indicate the magnitude of crosstalk in the U, V directions. As can be seen, the off-axis crosstalk errors are highest for the embodiments of FIGS. 9A, 9B, and 10, ranging from 32 to 45 mV / V for the X and Y axes, where 40% of the nominal signal range is thus crosstalk (i.e., (45 to 32) / 32 = 40%). The embodiments of Figures 3, 4, and 5 have off-axis crosstalk errors in the range of 16-20 mV / V for the X and Y axes, where 25% of the nominal signal range is thus crosstalk (i.e., (20-16) / 16 = 25%), a moderate improvement. The off-axis crosstalk errors are lowest for the embodiments of Figures 12A, 12B, and 13A-13F, where 7% of the nominal signal range is thus crosstalk (i.e., (16-15) / 15 = 7%).

[0122] FIG. 14D shows an example of the change in resonant transmitter frequency as the stylus position detector (SPDP) displacement varies between 0 mm and 2 mm for the embodiments shown in FIGS. 3, 4, and 5, the embodiments shown in FIGS. 9A, 9B, and 10, and the embodiments shown in FIGS. 12A, 12B, and 13A-13F. At 0 mm displacement, the resonant frequency is the same for the various embodiments. The resonant frequency change (RFC) at 2 mm SPDP displacement is greatest for the embodiments of FIGS. 9A, 9B, and 10 (labeled SPDP1011 in FIG. 14D) and least for the embodiments of FIGS. 12A, 12B, and 13A-13F (labeled SPDP1311 in FIG. 14D). The embodiment of Figures 3, 4, and 5 (labeled SPDP411 in Figure 14D) has an RFC that is slightly larger than that of the embodiments of Figures 12A, 12B, and 13A-13F, but significantly smaller than that of the embodiments of Figures 9A, 9B, and 10. As can be seen, the embodiments of Figures 12A, 12B, and 13A-13F have less change in inductance with changing displacement along the Z axis, resulting in a smaller RFC at the disruptor location in addition to minimal off-axis crosstalk.

[0123] In various embodiments, particularly in single-substrate embodiments, at least some signal offset errors may occur due to printed circuit board (PCB) manufacturing tolerances, such as inter-layer coil registration errors. For example, misalignment between a field-generating coil arrangement and a rotational detection coil arrangement (RSC) may occur due to substrate manufacturing tolerances. In accordance with principles disclosed herein, one or more misalignment compensation elements may be added to a coil substrate arrangement to compensate for misalignment of the coils (e.g., coils of the first, second, and / or center substrate portion coil arrangements, etc.) relative to one another. More specifically, as described in more detail below, various embodiments may configure / utilize one or more misalignment compensation elements to reduce signal offsets resulting from misalignment of at least one coil of a coil substrate arrangement (e.g., a coil substrate arrangement may comprise a printed circuit board having multiple layers on which coils are disposed, and misalignment of at least one coil may result from registration errors, such as within manufacturing tolerances, in inter-layer registration as part of the manufacturing process).

[0124] 15A-15C show embodiments in which the misalignment compensation element takes the form of shielding added to reduce the effects of registration errors between a field-generating coil arrangement (e.g., field-generating coils 1261T and 1261B of FIG. 12B) and a rotating detection coil (rotating detection coil arrangement) (e.g., TRSC1-TRSC4 and BRSC1-BRSC4 of FIG. 12B). FIG. 15A illustrates an inner shielding, in which copper pads are added to the field-generating coil (e.g., field-generating coils 1261T and 1261B of FIG. 12B), and an outer shielding 1263, in which copper pads are located on the exterior of the shielded field-generating coil 1261′. 15B is a top view illustrating the alignment of the shielded field-generating coil 1261′ with the rotational detection coil (rotational detection coil configuration) RSC (e.g., TRSC1-TRSC4 or BRSC1-BRSC4) and the outer shielding 1263 with respect to the central axis of the stylus position detection portion (e.g., central axis CA in FIG. 13A ). As shown, copper pads have been added to the field-generating coil 1261 to extend the area of ​​the shielded field-generating coil 1261′ to generally match the area of ​​the inner loop of the rotational detection coil RSC. And, the copper pads of the outer shielding 1263 are shaped and positioned to generally match the area of ​​the outer loop of the rotational detection coil RSC.

[0125] 15C illustrates an exemplary embodiment of layers of a coil substrate construction 1590. As shown, the coil substrate construction 1590 comprises an upper coil substrate section 1590T and a lower coil substrate section 1590B. The upper coil substrate section 1590T, in order, comprises a first layer having an upper axial detection coil construction TASCC, a second layer having at least a first shielded upper field generating coil construction 1261T′ and an outer shield 1263T, a third layer having N upper rotational detection coils TRSC, and an upper normalization coil construction TR N The lower coil substrate section 1590B is generally a mirror image of the upper coil substrate section 1590T and includes a lower normalized coil configuration BR Na second layer having N lower rotating detection coils BRSC; a third layer having at least a first shielded lower field generating coil arrangement 1261B′ and an outer shield 1263B; and a fourth layer having a lower axial detection coil arrangement BASCC.

[0126] Some embodiments may employ inner shielding (e.g., shielded field-generating coil 1261′) without outer shielding (e.g., outer shielding 1263), some embodiments may employ outer shielding (e.g., outer shielding 1263) without inner shielding (e.g., shielded field-generating coil 1261′), and some embodiments may employ both inner shielding (e.g., shielded field-generating coil 1261′) and outer shielding (e.g., outer shielding 1263). Shielding 1261′, 1263 makes the generated field smaller and more uniform at the ends of the rotating detection coil, reducing the effects of registration errors between the field-generating coil and the rotating detection coil. As shown in the table below, inner and outer shielding facilitates a 77% reduction in offset with only a 5% reduction in gain.

[0127] [Table 1]

[0128] Referring to FIG. 12B , FIG. 16 illustrates an exemplary embodiment of a stylus position detection unit 1211′ in which a misalignment compensation element in the form of a pin 1298 (which may, for example, in various embodiments, comprise a pin, pad, or the like) is added to the coil substrate structure to compensate for signal offset errors by introducing a compensating offset signal. In various embodiments, the pin can extend through the entire coil substrate structure, or only a portion thereof, or may be disposed on one layer of the coil substrate structure. As shown, the one or more pins may include multiple pins disposed on one side of the coil substrate structure 1290′ relative to a plane containing the central axis (see, for example, FIG. 13A ). The pins are then generally parallel to the central axis to compensate for misalignment of one or more rotational detection coils with respect to the field-generating coil structure. More specifically, in various embodiments, the pin arrangement may be utilized to increase or decrease the magnetic field through individual coils to compensate for coil misalignment.

[0129] With reference to FIG. 12B, FIG. 17A shows an exemplary embodiment of a stylus position detector 1211″ in which a mechanical adjustment mechanism 1297 is used to adjust the relative position of the coil substrate assembly 1290″ and / or the disruptor assembly 1250 (e.g., the relative X, Y and / or Z position of the coil substrate assembly 1290″ or the disruptor assembly 1250 relative to each other and / or relative to the housing / enclosure of the coil substrate assembly 1290″). In various embodiments, the coil substrate assembly 1290″ can include additional spacing (e.g., at the ends and / or center) to provide an adjustable positioning range. It will be appreciated that the mechanical adjustment mechanism 1297 may be utilized to reduce misalignment conditions. In an exemplary embodiment, overall correction for misalignment may be provided using one or more other misalignment compensation elements (e.g., pads or pins 1298 of FIG. 16, shielding 1261′ (shielded field generating coil 1261′) of FIGS. 15A-15C, 1263, adjustable coil TASCC′ (described below) of FIGS. 18A-18C, etc., and / or various combinations thereof), with fine position adjustment provided by mechanical adjustment mechanism 1297 to reduce any residual misalignment error or improve the effectiveness of other misalignment compensation elements.

[0130] As shown, the mechanical position adjustment mechanism 1297 includes set screws 1297A, 1297B. A first set screw 1297A (or multiple first set screws 1297A) facilitates adjustment of the relative XY position of the coil substrate assembly 1290″, and a second set screw 1297B facilitates adjustment of the Z position of the disruptor assembly 1250 with respect to the coil substrate assembly 1290″. In various embodiments, the set screws 1297A pass through and adjust the position of the alignment and mounting portion 1217 to which the coil substrate assembly 1290″ is attached or otherwise coupled. An enclosure 1208′ (e.g., part of or coupled to a body frame such as frame 408 in FIG. 4) surrounds the coil substrate assembly 1290″ and includes spacers SP that operate in conjunction with the relative movement. As described above (e.g., with respect to FIG. 12A ), the disruptor element 1251 travels within the hole 1291 in the coil substrate structure 1290″ and is coupled to the stylus suspension (see, e.g., suspension 307 / 407 / 407′ in FIGS. 2-4 ) by a coupling structure 1253 that comprises an upper portion of the moving member 1212 (e.g., similar to moving member 412 in FIGS. 3 and 4 ). In various embodiments, the second set screw 1297B may be included as part of the coupling structure 1253 or may operate in conjunction with the coupling structure 1253, such that the coupling structure 1253 may be at least partially adjustable. To that end, as described above, the second set screw 1297B facilitates adjustment of the Z position of the disruptor element 1251 relative to the coil substrate structure 1290″.

[0131] 4, FIG. 17B illustrates an exemplary embodiment of a stylus position detector 511″ in which a mechanical adjustment mechanism 597 is used to adjust the relative position of the coil substrate arrangement 590″ and / or the disruptor arrangement 550 (e.g., the relative X, Y, and / or Z position of the coil substrate arrangement 590″ or the disruptor arrangement 550 relative to each other and / or the housing / enclosure of the coil substrate arrangement 590″, etc.). In various embodiments, the coil substrate arrangement 590″ (e.g., comprising the substrates 571T, 571B, and the field-generating coil 561 and / or its substrate) can include additional spacing (e.g., at the ends and / or center) to provide an adjustable positioning range. It will be appreciated that the mechanical adjustment mechanism 597 may be utilized to reduce misalignment conditions, similar to the operation described above with respect to FIG. 17A.

[0132] As shown, the mechanical position adjustment mechanism 597 includes set screws 597A, 597B. A first set screw 597A (or multiple first set screws 597A) facilitates adjustment of the relative XY position of the coil substrate assembly 590'', and a second set screw 597B facilitates adjustment of the Z position of the disruptor assembly 550 with respect to the coil substrate assembly 590''. In various embodiments, the set screws 597A extend through and adjust the position of the alignment and mounting portion 517 to which the coil substrate assembly 590'' is attached or otherwise coupled. An enclosure 508' (which may be coupled to or part of a body frame, such as frame 408 in FIG. 4, for example) surrounds the coil substrate assembly 590'' and includes spacers SP that operate in conjunction with the relative movement. In various embodiments, the disruptor element 551 travels within a hole 591 in the coil substrate arrangement 590'' (e.g., within the field-generating coil 561 and its substrate) and is coupled to the stylus suspension (see, e.g., stylus suspension 307 / 407 / 407' in Figures 2-4) by a coupling arrangement 553 that includes an upper portion of the moving member 412. In various embodiments, the second set screw 597B may be included as part of the coupling arrangement 553 or may operate in conjunction with it. The coupling arrangement 553 may thus be at least partially adjustable such that, as described above, the second set screw 597B facilitates adjustment of the Z position of the disruptor element 551 relative to the coil substrate arrangement 590''. In various embodiments, a portion of the second set screw 597B, the moving member 412, and / or other portions of the coupling construct 553 can move within the hole 591B in the substrate 571B (e.g., in some embodiments, the substrate 571T can include a similar hole 591T that can provide access to the second set screw 597B for adjustment). With respect to Figures 17A and 17B, it will be understood that certain components shown with or without hash lines may include holes or openings (e.g., to allow certain relative motion, etc.).An example of such relative movement of the disruptor elements 551, 1251 within the respective stylus position detection units 511'', 1211'' may be understood based at least in part on the illustration of Figure 3 regarding the relative movement of the disruptor elements 451 within the stylus position detection unit 411.

[0133] With reference to FIG. 12B , FIGS. 18A-18C illustrate exemplary embodiments in which a misalignment compensation element in the form of a conductive short 1299 (e.g., a zero-ohm resistor) can be added to the coil substrate construction 1290′″ to compensate for misalignment errors. More specifically, in various embodiments, the conductive short 1299 can be added (e.g., at a location such as shown in FIGS. 18B and 18C ) to adjust the current path, essentially adjusting the coil dimensions of one or more adjustable coils of the coil substrate construction 1290′″, thereby effectively nulling or otherwise compensating for a certain determined offset. In various embodiments, the adjustable coils are in outer layers at the top and / or bottom of the coil substrate construction 1290′″ (e.g., adjacent to or as part of the axial detection coil constructions TASCC′ or BASCC′ in FIG. 18A ). As such, the conductive short 1299 can be easily added or removed without requiring access to inner layers of the coil substrate construction 1290′″.

[0134] In various embodiments, when the coil substrate construction is initially manufactured / produced, certain misalignment compensation elements (e.g., shields 1261′, 1263 in FIGS. 15A-15C ) may be included as part of the manufacturing / production (e.g., as a general technique to reduce any misalignment errors that may occur due to any misalignment of the coils). In various embodiments, after the coil substrate construction is manufactured / produced, measurements and / or testing may be performed to determine what offsets are present (e.g., due to coil misalignments that may have occurred during manufacturing / production). Based on such testing / measurements, a specific decision can be made regarding the application of one or more offset compensation techniques (e.g., such as those described above with respect to FIGS. 16 , 17A , 17B , and 18A-18C ). For example, with respect to the approaches of Figures 16, 18B, and 18C, based on such testing / measurements, a determination can be made as to where misalignment compensation elements (e.g., pins, conductive shorts, etc.) should be placed / located / added to compensate for the offset and achieve the desired offset-compensated configuration.

[0135] 17A and 17B, a determination can be made as to what and / or how much of one or more adjustments to make to compensate for the offset (e.g., the remaining offset) and achieve a desired offset-compensated configuration based on such testing / measurements (e.g., which may be performed initially and / or after techniques such as those of FIGS. 16, 18B, and 18C have been performed to make larger adjustments and the techniques of FIGS. 17A and 17B have been performed to make finer adjustments). In various embodiments, multiple iterations of one or more correction techniques (e.g., including iterative testing and / or active monitoring of any prescribed offsets, etc.) can be performed, including continuing adjustments until a desired offset-compensated configuration (e.g., a configuration in which the respective offset errors have been reduced to an acceptable level, etc.) is achieved.

[0136] Although Figures 15A-15C, 16, 17A, and 18A-18C have been generally described with reference to Figures 12B and 13A, the techniques described herein for compensating for and reducing / resolving offset errors can be used in other embodiments, such as those described above with respect to Figures 3, 4, and 5, and Figures 9A, 9B, and 10.

[0137] In some embodiments, the height of the cylindrical disruptor elements of the scanning probes disclosed herein along the Z direction may be equal to or greater than the height of the coil substrate arrangement along the Z direction. In some such embodiments, the height of the cylindrical disruptor elements along the Z direction may be at least 1.5 times greater than the height of the coil substrate arrangement along the Z direction.

[0138] In various embodiments, the coil substrate arrangement is configured to provide N complementary pairs of rotational detection coils CPi, each comprising an upper rotational detection coil TRSCi and a lower rotational detection coil BRSCi, characterized in that the shapes of their internal regions (upper rotational detection coil TRSCi and lower rotational detection coil BRSCi) nominally coincide when projected along the axial direction.

[0139] In various embodiments, the coil substrate arrangement is configured to provide N complementary pairs CPi of rotational detection coils, each comprising an upper rotational detection coil TRSCi and a lower rotational detection coil BRSCi, characterized in that the shapes of their internal regions (upper rotational detection coil TRSCi and lower rotational detection coil BRSCi) are nominally identical when rotated about a central axis such that the shape of one of them matches the angular position of the other about the central axis and then projected along the axial direction.

[0140] In some embodiments, the scanning probe may comprise a translation member coupled to a cylindrical disruptor element and a stylus coupling portion and may extend generally along a central axis.

[0141] In some embodiments, the method includes generating drive control signals for controlling a drive mechanism that moves the scanning probe as disclosed herein along the surface of the workpiece, and generating three-dimensional position information based on induced detection signals generated by the scanning probe as it moves along the surface of the workpiece.

[0142] In some embodiments, a system comprises a scanning probe as disclosed herein, a drive mechanism, and a mount configured to couple the scanning probe to the drive mechanism, hi some such embodiments, the system comprises a motion controller that controls movement of the drive mechanism.

[0143] In various embodiments, the field-generating coil arrangement of a system as disclosed herein comprises a first field-generating coil arrangement and a second field-generating coil arrangement, each surrounding a hole in the coil substrate arrangement and correspondingly surrounding the disruptor movement volume. In some such embodiments, the first field-generating coil arrangement and the second field-generating coil arrangement comprise a pair of planar field-generating coils located approximately equidistant from the midplane of the disruptor movement volume along the central axis and nominally planar and orthogonal to the central axis. In some such embodiments, the upper and lower axial detector coil arrangements also surround the hole in the coil substrate arrangement and correspondingly surround the disruptor movement volume. In some such embodiments, the coil substrate arrangement has an upper and lower portion. The upper portion comprises first, second, and third layers, each comprising an upper axial detector coil arrangement, a first field-generating coil arrangement, and N upper rotational detector coils, respectively. The lower portion is a mirror image of the upper portion and correspondingly comprises first, second, and third layers each comprising a lower axial detector coil arrangement, a second field generating coil arrangement, and N lower rotational detector coils. The coil substrate arrangement is mounted in fixed relationship to the frame of the scanning probe, with the lower portion of the coil substrate arrangement closer to the stylus suspension. The upper and lower portions of the coil substrate arrangement are nominally parallel to each other and nominally perpendicular to the central axis.

[0144] While preferred embodiments of the present disclosure have been illustrated and described, numerous variations on the illustrated and described arrangements of features and sequences of operations will be apparent to those skilled in the art based on this disclosure. Various alternatives can be used to implement the principles disclosed herein. Furthermore, the various embodiments described above can be combined to provide further embodiments. All U.S. patents and U.S. patent applications mentioned herein are incorporated herein by reference in their entirety. Aspects of the embodiments can be modified, employing concepts from the various patents and applications to provide further embodiments as needed.

[0145] These and other changes can be made to the embodiments in light of the above detailed description. Generally, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full range of equivalents to which such claims are entitled.

Claims

1. In a scanning probe for a coordinate measuring machine, a stylus coupling portion configured to be rigidly coupled to a stylus; a stylus movement mechanism configured to allow axial movement of the stylus coupling portion along an axial direction and rotational movement of the stylus coupling portion about a center of rotation; a stylus suspension coupled to a frame of the scanning probe, the stylus suspension comprising: a field generating coil arrangement surrounding the bore; an upper axial detector coil arrangement and a lower axial detector coil arrangement; N upper rotation detection coils and N lower rotation detection coils (N is an integer of at least 3); a coil substrate structure mounted in fixed relationship to the frame of the scanning probe; a disruptor structure comprising a cylindrical disruptor element arranged along a central axis of a disruptor movement volume, the disruptor element being configured to move and fit within the hole in the coil substrate structure and providing a disruptor region, the disruptor element being configured to move and fit within the hole in the coil substrate structure and coupled to the stylus suspension by a coupling structure; the cylindrical disruptor element moves through an operational range of motion along the axial direction of + / -Rz in response to the axial translation and through respective operational ranges of motion along orthogonal X and Y directions orthogonal to the axial direction of + / -Rx and + / -Ry in response to the rotational translation, the cylindrical disruptor element moves within the disruptor movement volume to an undeflected position in response to deflection of the stylus suspension, the field generating coil arrangement generates a varying magnetic flux within the disruptor movement volume generally along the axial direction in response to coil drive signals, a stylus position detection portion disposed along the central axis that is parallel to the axial direction and nominally aligned with the center of rotation; a signal processing and control circuit operatively connected to the coils of the stylus position detector to provide the coil drive signals, the signal processing and control circuit being configured to receive signals from the coil substrate arrangement comprising respective signal components provided by the upper axial detector coil, the lower axial detector coil, the upper rotational detector coil and the lower rotational detector coil of the coil substrate arrangement, and to output signals indicative of the axial and rotational position of the cylindrical disruptor element or the stylus relative to the frame of the scanning probe; A scanning probe comprising:

2. 2. The scanning probe of claim 1, 10. The scanning probe of claim 9, wherein the field generating coil arrangement comprises a first field generating coil arrangement and a second field generating coil arrangement, each surrounding the hole in the coil substrate arrangement and correspondingly surrounding the disruptor movement volume.

3. 3. The scanning probe of claim 2, 10. A scanning probe comprising: a pair of planar field-generating coils positioned approximately equidistant from a midplane of the disruptor movement volume along the central axis, the first and second field-generating coil arrangements being nominally planar and orthogonal to the central axis.

4. 3. The scanning probe of claim 2, The upper and lower axial detector coil arrangements also surround the hole in the coil substrate arrangement and correspondingly surround the disruptor movement volume.

5. 3. The scanning probe of claim 2, the coil substrate structure has an upper portion and a lower portion; the upper portion comprises first, second, and third layers each comprising the upper axial detector coil arrangement, the first field generating coil arrangement, and the N upper rotational detector coils; the lower portion is a mirror image of the upper portion and correspondingly comprises first, second, and third layers each comprising the lower axial detector coil arrangement, the second field generating coil arrangement, and the N lower rotational detector coils, respectively; the coil substrate structure is mounted in fixed relationship to the frame of the scanning probe with the lower portion of the coil substrate structure closer to the stylus suspension; A scanning probe wherein the upper and lower portions of the coil substrate structure are nominally parallel to one another and nominally perpendicular to the central axis.

6. 6. The scanning probe of claim 5, the coil substrate structure comprises a normalization coil structure having an upper normalization coil as part of the upper portion and a lower normalization coil as part of the lower portion; 10. A scanning probe, wherein the normalization coil arrangement is utilized to provide a measurement of the varying magnetic flux generated by the first and second field generating coil arrangements.

7. 6. The scanning probe of claim 5, A scanning probe wherein said upper and lower portions are part of a single multi-layer printed circuit board.

8. 2. The scanning probe of claim 1, 10. A scanning probe according to claim 9, wherein a height of said cylindrical disruptor element along a Z direction is equal to or greater than a height of said coil substrate structure along said Z direction.

9. 2. The scanning probe of claim 1, 10. A scanning probe comprising: a cylindrical disruptor element having a height along the Z direction that is at least 1.5 times greater than a height of the coil substrate structure along the Z direction.

10. 2. The scanning probe of claim 1, the coil substrate structure is configured to provide N complementary pairs of rotation detection coils each comprising the upper rotation detection coil and the lower rotation detection coil, each complementary pair comprising the upper rotation detection coil and the lower rotation detection coil, and wherein shapes of internal regions of the upper rotation detection coil and the lower rotation detection coil nominally coincide when projected along the axial direction.

11. 2. The scanning probe of claim 1, the coil substrate structure is configured to provide N complementary pairs of rotational detection coils, each comprising the upper rotational detection coil and the lower rotational detection coil, wherein when rotated about the central axis such that the shape of one of the upper rotational detection coil and the lower rotational detection coil matches the angular position of the other about the central axis and then projected along the axial direction, the shapes of inner regions of the upper rotational detection coil and the lower rotational detection coil nominally match.

12. 2. The scanning probe of claim 1, a moving member coupled to the cylindrical disruptor element and the stylus coupling portion; wherein the moving member extends generally along the central axis.

13. moving a scanning probe along a surface of a workpiece; generating three-dimensional position information based on inductive detection signals generated by the scanning probe as it moves along the surface of the workpiece; A method comprising: The scanning probe a stylus coupling portion configured to be rigidly coupled to a stylus; a stylus movement mechanism configured to allow axial movement of the stylus coupling portion along an axial direction and rotational movement of the stylus coupling portion about a center of rotation; a stylus suspension coupled to a frame of the scanning probe, the stylus suspension comprising: a field generating coil arrangement surrounding the bore; an upper axial detector coil arrangement and a lower axial detector coil arrangement; N upper rotation detection coils and N lower rotation detection coils (N is an integer of at least 3); a coil substrate structure comprising: a disruptor structure comprising a cylindrical disruptor element arranged along a central axis of a disruptor movement volume, the disruptor element being configured to move and fit within the hole in the coil substrate structure and providing a disruptor region, the disruptor element being configured to move and fit within the hole in the coil substrate structure and coupled to the stylus suspension by a coupling structure; the cylindrical disruptor element moves through an operational range of motion along the axial direction of + / -Rz in response to the axial translation and through respective operational ranges of motion along orthogonal X and Y directions orthogonal to the axial direction of + / -Rx and + / -Ry in response to the rotational translation, the cylindrical disruptor element moves within the disruptor movement volume to an undeflected position in response to deflection of the stylus suspension, the field generating coil arrangement generates a varying magnetic flux within the disruptor movement volume generally along the axial direction in response to coil drive signals, a stylus position detection portion disposed along the central axis that is parallel to the axial direction and nominally aligned with the center of rotation; a signal processing and control circuit operatively connected to the coils of the stylus position detector to provide the coil drive signals, the signal processing and control circuit being configured to receive signals from the coil substrate arrangement comprising respective signal components provided by the upper axial detector coil, the lower axial detector coil, the upper rotational detector coil and the lower rotational detector coil of the coil substrate arrangement, and to output signals indicative of the axial and rotational position of the cylindrical disruptor element or the stylus relative to the frame of the scanning probe; Equipped with A method characterized by:

14. The method of claim 13 further comprising: generating a drive control signal for controlling a drive mechanism that moves the scanning probe along the surface of the workpiece.

15. a scanning probe; A drive mechanism; a mount for attaching the scanning probe to the drive mechanism, The scanning probe a stylus coupling portion configured to be rigidly coupled to a stylus; a stylus movement mechanism configured to allow axial movement of the stylus coupling portion along an axial direction and rotational movement of the stylus coupling portion about a center of rotation; a stylus suspension coupled to a frame of the scanning probe, the stylus suspension comprising: a field generating coil arrangement surrounding the bore; an upper axial detector coil arrangement and a lower axial detector coil arrangement; N upper rotation detection coils and N lower rotation detection coils (N is an integer of at least 3); a coil substrate structure comprising: a disruptor structure comprising a cylindrical disruptor element arranged along a central axis of a disruptor movement volume, the disruptor element being configured to move and fit within the hole in the coil substrate structure and providing a disruptor region, the disruptor element being configured to move and fit within the hole in the coil substrate structure and coupled to the stylus suspension by a coupling structure; the cylindrical disruptor element moves through an operational range of motion along the axial direction of + / -Rz in response to the axial movement, and through an operational range of motion along respective orthogonal X and Y directions orthogonal to the axial direction of + / -Rx and + / -Ry in response to the rotational movement, the cylindrical disruptor element moves within the disruptor movement volume to an undeflected position in response to deflection of the stylus suspension, the field generating coil arrangement generates a varying magnetic flux within the disruptor movement volume generally along the axial direction in response to coil drive signals, a stylus position detection portion disposed along the central axis that is parallel to the axial direction and nominally aligned with the center of rotation; a signal processing and control circuit operatively connected to the coils of the stylus position detector to provide the coil drive signals, the signal processing and control circuit being configured to receive signals from the coil substrate arrangement comprising respective signal components provided by the upper axial detector coil, the lower axial detector coil, the upper rotational detector coil and the lower rotational detector coil of the coil substrate arrangement, and to output signals indicative of the axial and rotational position of the cylindrical disruptor element or the stylus relative to the frame of the scanning probe; Equipped with A system characterized by:

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