Patent Publication Number: US-2013241761-A1

Title: Beam steering for laser radar and other uses

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to and the benefit of U.S. Provisional Application 61/659,795, filed Jun. 14, 2012, and U.S. Provisional Application No. 61/612,022, filed Mar. 16, 2012, both of which are incorporated herein by reference in their respective entireties. This application is also related to U.S. patent application Ser. No. ______, entitled “Light-Beam Scanning for Laser Radar and Other Uses,” filed concurrently with the present application and incorporated herein by reference. 
     FIELD 
     This disclosure pertains to, inter alia, imparting a scanning or sweeping motion to a beam of light, for example a laser beam. The devices and methods disclosed herein can be used, for example, to impart a scanning or sweeping motion to an interrogation beam produced by a laser radar system. 
    
    
     BACKGROUND 
     Various applications have been developed for using substantially collimated beams of light that are directed onto the surface of a object. One application, called laser radar, involves directing a laser beam to an object or site called a “target” herein. Laser radar (also called “LIDAR” or “LADAR”) is a remote-sensing technique used for measuring distance to and/or surface properties of a target by illuminating the target surface with light pulses produced by a laser. Laser radar systems are particularly useful for inspection applications in which large objects or complex surfaces are to be measured such as in the manufacture and assessment of aircraft, automobile, wind turbine, satellite, marine, and other oversized parts. Some conventional laser radar systems are described in the following U.S. Pat. Nos. 4,733,609; 4,824,251; 4,830,486; 4,969,736; 5,114,226; 7,139,446; and 7,925,134; and in Japan Patent No. 2,664,399, all of which are incorporated herein by reference to the fullest extent allowed by law. In these conventional laser radar systems, a laser beam (called an “interrogation beam”) is directed to and scanned over a region of the target surface. Portions of the interrogation beam that are reflected or scattered back from the target to the laser radar system are detected, and the resulting signals are processed to produce usable information about the target. 
     Referring to  FIG. 18 , a conventional laser radar system  250  typically comprises the following subsystems: (a) a source  252  of a light beam  253  (e.g., laser beam), (b) a beam-shaping optical system  254  that receives the beam  253  from the source and directs, shapes, and focuses the beam into an interrogation beam  255 , (c) a sending optical system  256  that directs the interrogation beam  255  to a target  258 , (d) a scanning device  260  that imparts motion to the beam-shaping optical system  254  and sending optical system  256  so as to scan the interrogation beam over a selected region on the target surface (for laser radar, beam scanning is usually one or both of azimuth and elevation), (e) a receiving optical system  262  that receives light  257  (from the interrogation beam  255 ) reflected from the target back to the system  250  (the receiving optical system  262  includes a photodetector, not detailed, that produces an electronic signal corresponding to the received light  257 ), and (f) a signal-processing system that converts the signal from the photodetector into usable data concerning the scanned region of the target. The beam-shaping optical system  254  and sending optical system  256  collectively have large mass, which limits the rate at which the scanning device  260  can move them. I.e., the maximum achievable beam-scanning rate is adversely affected by the mass that must be moved by the scanning device  260 . The resulting compromised scanning rate can limit the rate at which the system  250  produces information about the target. 
     Therefore, there is a need for beam-scanning systems of which the mass that is actually moved to achieve scanning of the beam is substantially less than in conventional systems, and hence are less limited in the rates at which the beam can be moved in a scanning manner. 
     SUMMARY 
     The needs articulated above are met by systems and methods as disclosed herein, of which a first aspect is directed to optical systems. An exemplary embodiment of an optical system comprises a beam-forming unit, a beam-scan unit, and a controller. The beam-forming unit comprises a first optical element, and the beam-scan unit comprises a second optical element. The first optical element is movable to shape and direct an optical beam along a nominal propagation axis to a target, and the second optical element comprises at least one movable beam deflector that moves the optical beam in a scanning manner relative to the nominal propagation axis. The controller is coupled to the beam-forming unit and beam-scan unit and configured to induce movement of the first optical element required for shaping and directing the optical beam along the nominal propagation axis and to induce movement of the beam deflector of the second optical element as required to scan the optical beam relative to the nominal propagation axis. In many embodiments the second optical element comprises a rotary actuator coupled to the controller and to which the second optical element is coupled, wherein the controller is configured to actuate the rotary actuator as required to rotate the optical beam. 
     The system can further comprise a transmit/receive system coupled to the controller and configured to send the optical beam to the target and to receive at least a portion of the optical beam as reflected from the target. The transmit/receive system can further comprise a source of the optical beam. For example, the source comprises a laser. 
     It is desirable for the motion of the second optical element to be independent of motion of the first optical element so that the scanning mass may be minimized. The first optical element can be used to adjust one or more of: width of the beam, shape of the beam, and direction of the beam. 
     In many embodiments the first optical element is a reflective optical element. Desirably, the reflective optical element is a corner cube situated to receive the optical beam from a light source. The second optical element can be a refractive optical element (e.g., a wedge prism) or a reflective optical element (e.g., a mirror) situated to receive the optical beam from the corner cube and configured to return the optical beam to the corner cube as the second optical element is being moved relative to the corner cube. 
     The beam-forming unit can further comprise a focus-adjust device, while the beam-scan unit further comprises a movement-adjust device. In certain embodiments the focus-adjust device is coupled to the first optical element and to the controller to move the first optical element as required to focus the optical beam on the target. Meanwhile, the movement-adjust device is coupled to the second optical element and to the controller to adjust at least one parameter associated with movement of the beam deflector. The beam-forming unit can further comprise a reflective optical element, wherein, for example, the focus-adjust device adjusts a linear position of the reflective optical element as required to focus the optical beam on the target. 
     Another embodiment of an optical system comprises a beam-shaping optical system, a movable beam deflector, and a beam-scan controller. The beam-shaping optical system produces an optical beam. The movable beam deflector directs the optical beam to a target. The beam-scan controller is operably coupled to the beam deflector to produce an optical-beam scan angle based on an orientation of at least a portion of the beam-shaping optical system and an angle (e.g., rotation angle) of the beam deflector. Certain embodiments are configured as a laser radar system, wherein the optical beam is an interrogation beam. 
     The beam-scan controller desirably is configured to establish a plurality of scan angles such that the optical beam is scanned in a desired scan pattern as incident on the target. In certain embodiments the beam-scan controller is configured to direct the optical beam in a pointing direction based on an orientation of at least a portion of the beam-shaping optical system, wherein the beam deflector has an axis of rotation that is parallel to the optical-beam pointing direction. 
     In many embodiments the rotatable beam deflector comprises at least one rotatable wedge prism or rotatable mirror. The rotatable wedge prism or mirror can be situated so that the optical beam produced by the beam-shaping optical system is incident at an angle to the prism or mirror corresponding to a minimum deviation by the prism or mirror. 
     In some embodiments the beam deflector is rotatable, comprising a rotation stage, with a rotatable optical element being coupled to the rotation stage. 
     The movable beam deflector can comprise a first rotatable wedge prism having a first wedge angle and a second rotatable wedge prism having a second wedge angle. In some embodiments the first wedge angle and the second wedge angle are equal. The systems can further comprise first and second rotation stages coupled to the first and second rotatable wedge prisms, respectively. 
     Certain embodiments further comprise an optical detection system that is configured to receive at least a portion of the interrogation optical beam from the target and to produce a target assessment based on the received portion. The target assessment can be associated with a target distance or a target shape. The beam-scan controller can be configured to establish an interrogation-beam pointing direction based on an orientation of at least a portion of the beam-shaping optical system and to rotate the scan angle about the pointing direction so as to define a scan path. The target assessment produced by the optical detection system in these embodiments can be at least one of a target dimension or a target surface profile. 
     Some embodiments further comprise an optical detection system configured to receive at least a portion of the interrogation optical beam from the target and to produce a target assessment based on the received portions and the associated scan angles. The beam-scan controller can be configured to establish an interrogation optical beam pointing direction based on an orientation of at least a portion of the beam-shaping optical system and to rotate the scan angle about the orientation so as to define a scan path, wherein the target assessment produced by the optical detection system is at least one of a target feature dimension or target feature location. 
     According to another aspect, methods are provided. An embodiment of the method comprises establishing a beam orientation of an optical beam along a nominal propagation axis using a beam-shaping optical system. The optical beam is scanned about the nominal propagation axis using a movable beam deflector. The scanned beam is delivered to a target. At least a portion of the beam back from the target is received, and a characteristic of the target is determined based on the received portion. 
     By way of example and not intending to be limiting, the beam can be scanned along a circular path relative to the nominal propagation axis. The range of possible scan patterns is substantially unlimited. 
     The method can further comprise adjusting the optical beam orientation based on the determined target characteristic, and re-determining the target characteristic. Additionally the orientation of the optical beam can be established with respect to a selected target feature, wherein, using the beam deflector, the optical beam is scanned about the selected target feature. 
     In many embodiments the movable beam deflector comprises a refractive optical element such as but not limited to a wedge prism, wherein scanning of the optical beam is produced by deviating the optical beam by transmission through the wedge prism. The wedge prism can be situated at an angle associated with a minimum optical beam deviation. Alternatively, the movable beam deflector comprises a reflective optical element. 
     According to another aspect, apparatus are provided, of which a representative embodiment comprises a beam-forming optical system, a primary beam scanner, a secondary beam scanner, and an optical detection system. The beam-forming optical system is configured to produce an optical beam. The primary beam scanner is situated and configured to produce a primary scan of the optical beam, using the beam-forming optical system. The secondary beam scanner is situated and configured to receive the optical beam from the primary beam scanner and produce a secondary scan, such that the scanning optical beam is directed along a scan path defined by the primary and secondary beam scanners. The optical detection system is configured to estimate target distances associated with at least a portion of the scan path based on portions of the optical beam received from the target. The apparatus can further comprise a scan controller configured to establish the primary scan based on an at least one target distance produced by the optical detection system. 
     In many embodiments the secondary beam scanner includes at least one wedge prism (as an exemplary refractive optical element) situated to receive the optical beam from the primary beam scanner and transmit the received optical beam along the scan path. The secondary beam scanner can include at least a first wedge prism and a second wedge prism. The first wedge prism in many examples is situated and configured to receive the optical beam from the primary beam scanner and to transmit the received optical beam to the second wedge prism. Meanwhile the second wedge prism can be situated and configured to transmit the optical beam from the first wedge prism along the scan path. 
     According to another aspect, laser radar apparatus are provided. An embodiment of such an apparatus comprises an optical fiber situated to emit an optical beam along an axis. A corner cube is situated along the axis so as to receive the emitted optical beam. A displacement stage is coupled to the corner cube and configured to displace the corner cube along the axis. A return reflector is situated along the axis to receive the emitted optical beam from the corner cube and reflect the emitted optical beam as a returned beam to the corner cube. A beam-forming lens is situated along the axis to receive the returned beam from the corner cube and produce an interrogation beam. A focus controller is coupled to the displacement stage and configured to adjust a separation of the corner cube and the beam forming lens so as to focus the interrogation beam at a selected target distance. A primary beam scanner is configured to direct the axis toward a selected target location. A secondary beam scanner coupled to produce a motion of a scanning optical element so as to produce an angular deviation of the interrogation beam with respect to the axis so as to define a scan path. 
     In some embodiments the laser radar further comprises an optical receiver system configured to detect at least portions of the interrogation optical beam returned from a target, and a processor. The processor is coupled to the optical receiver systems and configured to determine a target characteristic for at least a portion of the target based on the detected portions of the interrogation optical signal and the scan path. The laser radar can further comprise a movable optical element (e.g., a rotatable wedge prism or mirror), wherein the secondary beam scanner is coupled to produce a motion of the optical element. The laser radar can further comprise a rotatable reflective surface, wherein the secondary beam scanner is coupled to produce a rotation of the rotatable reflective surface. 
     Thus, among the aspects described herein, laser radar and other precision systems are provided that comprise a beam-shaping optical system configured to produce an interrogation optical beam that can be scanned over a small angle using a lightweight movable beam deflector. Using this movable beam deflector allows beam scanning to be performed without having to move the primary optical assembly and associated mechanics. Such a beam deflector can be situated to receive the interrogation optical beam from the beam-shaping optical system and direct the interrogation optical beam to a target for scanning while the beam-shaping optical system remains fixed. A beam-scan controller establishes an interrogation-beam scan angle based on the orientation of at least a portion of the beam-shaping optical system and the posture of the beam deflector. In some embodiments, the beam-scan controller is configured to establish a plurality of scan angles such that the interrogation optical beam is scanned in an ellipse, a circle, a polygon, a w-shape, or in at least a portion of an arc, for example. In other embodiments, the beam-scan controller is configured to establish an interrogation-beam pointing direction based on an orientation of at least a portion of the beam-shaping optical system. In typical examples, the beam deflector comprises at least one rotatable wedge prism or other refractive optical element, or a rotatable mirror. In other representative examples, the optical element is situated so that the interrogation beam produced by the beam-shaping optical system is incident at an angle corresponding to a minimum deviation angle by the rotatable wedge prism. 
     In other representative examples, the rotatable beam deflector comprises a first rotatable wedge prism having a first wedge angle and a second rotatable wedge prism having a second wedge angle, wherein the first wedge angle and the second wedge angle can be the same or different. In some convenient embodiments, the first and second wedge prisms are rotatable so that the interrogation beam can be transmitted without deviation if desired. 
     The foregoing and additional features and advantages will be more readily understood from the following description, which proceeds with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of an embodiment of an optical system configured to scan a substantially collimated light beam over a region of interest on a target. 
         FIG. 2  is a block diagram of an alternative embodiment of an optical system configured to scan a substantially collimated light beam over a region of interest on a target. 
         FIG. 3  is a schematic diagram of an embodiment of an optical system configured to scan a substantially collimated light beam over a region of interest. 
         FIG. 4A  is a schematic diagram of an embodiment of a wedge-prism scanning assembly comprising two prisms. 
         FIG. 4B  is a schematic diagram of an embodiment of a wedge-prism scanning assembly comprising a wedge prism situated at a minimum deviation angle. 
         FIG. 4C  is a schematic diagram of an embodiment of a wedge-prism scanning assembly in which the wedge prism is situated on a tiltable base that provides beam scanning. 
         FIG. 5  is a block diagram of an embodiment of a method for evaluating a target using a scanned beam. 
         FIG. 6  is a schematic diagram of an embodiment of a laser radar system comprising a primary beam scanner and a secondary beam scanner based on a rotatable reflective surface. 
         FIG. 7  is a schematic diagram of an alternative embodiment of a scanning device based on rotation of a return mirror. 
         FIG. 8A  is a schematic diagram of an embodiment of a laser tracking system comprising a rotatable beam deflector. 
         FIGS. 8B-8C  depict representative rotatable beam deflectors suitable for the laser tracking system of  FIG. 8A . 
         FIG. 9A  is a schematic diagram of an embodiment of a secondary scanner comprising a beam deflector that is translatable so as to deflect a beam from a laser tracking system. 
         FIG. 9B  details facets of the beam deflector shown in  FIG. 9A . 
         FIG. 10  is a schematic diagram of an embodiment of a laser tracking system comprising a secondary scanner. 
         FIG. 11  is a schematic diagram of a representative embodiment of a secondary scanner based on a rotatable prism. 
         FIG. 12  is a schematic diagram of a representative embodiment of a secondary scanner based on a rotatable prism that serves as a return reflector. 
         FIG. 13  depicts an exemplary rotatable prism configured to serve as a beam deflector and a return reflector based on reflection from a back surface of the rotatable prism. 
         FIG. 14  is a schematic diagram of an embodiment of a secondary scanner based on a rotatable prism that is situated at a return reflector. 
         FIG. 15  is a block diagram of a representative embodiment of a method for tracking a tooling ball secured to a substrate or target. 
         FIG. 16  is a block diagram of a representative embodiment of a manufacturing system comprising a laser radar or other profile-measurement system for use in manufacturing components and for assessing whether the manufactured parts are defective or acceptable. 
         FIG. 17  is a block diagram of a representative embodiment of a manufacturing method comprising profile measurement to determine whether manufactured structures or components are acceptable, and whether one or more such manufactured structures can be repaired. 
         FIG. 18  is a schematic diagram of a conventional laser radar system. 
     
    
    
     DETAILED DESCRIPTION 
     The invention is described below in the context of representative embodiments that are not intended to be limiting in any way. 
     As used in this application and in the claims, the singular forms “a,” “an,” and “the” include the plural forms unless the context clearly dictates otherwise. Additionally, the term “includes” means “comprises.” Further, the term “coupled” does not exclude the presence of intermediate elements between the coupled items. 
     The systems, apparatus, and methods described herein should not be construed as limiting in any way. Instead, the present disclosure is directed toward all novel and non-obvious features and aspects of the various disclosed embodiments, alone and in various combinations and sub-combinations with one another. The disclosed systems, apparatus, and methods are not limited to any specific aspect or feature or combinations thereof, nor do the disclosed systems, apparatus, and methods require that any one or more specific advantages be present or problems be solved. Any theories of operation are to facilitate explanation, but the disclosed systems, methods, and apparatus are not limited to such theories of operation. 
     Although the operations of some of the disclosed methods are described in a particular, sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement, unless a particular ordering is required by specific language set forth below. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed systems, methods, and apparatus can be used in conjunction with other systems, methods, and apparatus. Additionally, the description sometimes uses terms like “produce” and “provide” to describe the disclosed methods. These terms are high-level abstractions of the actual operations that are performed. The actual operations that correspond to these terms will vary depending on the particular implementation and are readily discernible by one of ordinary skill in the art. 
     In the following description, certain terms may be used such as “up,” “down,” “upper,” “lower,” “horizontal,” “vertical,” “left,” “right,” and the like. These terms are used, where applicable, to provide some clarity of description when dealing with relative relationships. But, these terms are not intended to imply absolute relationships, positions, and/or orientations. For example, with respect to a target or other object, an “upper” surface can become a “lower” surface simply by turning the target over. Nevertheless, it is still the same object. 
     The systems, apparatus, and methods described herein should not be construed as being limiting in any way. Instead, the present disclosure is directed toward all novel and non-obvious features and aspects of the various disclosed embodiments, alone and in various combinations and sub-combinations with one another. The disclosed systems, methods, and apparatus are not limited to any specific aspect or feature or combinations thereof, nor do the disclosed systems, methods, and apparatus require that any one or more specific advantages be present or problems be solved. Any theories of operation set forth herein are to facilitate explanation; but, the disclosed systems, methods, and apparatus are not limited to such theories of operation. 
     Although the operations of some of the disclosed methods are described in a particular, sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement, unless a particular ordering is required by specific language set forth below. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed systems, methods, and apparatus can be used in conjunction with other systems, methods, and apparatus. Additionally, the description sometimes uses terms like “produce” and “provide” to describe the disclosed methods. These terms are high-level abstractions of the actual operations that are performed. The actual operations that correspond to these terms will vary depending on the particular implementation and are readily discernible by one of ordinary skill in the art. 
     For convenience in the following description, the terms “light” and “optical radiation” refer to propagating electromagnetic radiation that is directed to one or more targets or other loci to be profiled, detected, or otherwise investigated. Such radiation can be referred to as propagating in one or more “beams” that typically are based on optical radiation produced by a laser. In addition, such beams can have a spatial extent associated with one or more laser transverse modes, and can be substantially collimated and/or focused. As used herein, a beam having a wavelength λ is “substantially collimated” if an associated beam divergence (or convergence) angular diameter β is less than about 0.05, 0.01, or 0.005. In some examples, a substantially collimated beam has a divergence or convergence such that a ratio of a beam diameter at a target to a beam diameter as emitted to the target is less than 2:1, 1.5:1 or 1.2:1. Alternatively, collimation can be associated with beams such that a source-to-target distance is less than about 0.5, 1.0, 2.0, or 4.0 times a Rayleigh range associated with the beam. 
     For convenience, beams are described as propagating along one or more axes. Such axes generally are based on one or more line segments so that an axis can include a number of non-colinear segments as the axis is bent or folded or otherwise responsive to mirrors, prisms, lenses, and other optical elements. The term “lens” is used herein to refer to a single refractive optical element (a singlet) or a compound lens that includes one or more singlets, doublets, or other elements. In some examples, beams are shaped or directed by refractive optical elements; but, in other examples, reflective optical elements such as mirrors are used, or combinations of refractive and reflective elements are used. Such optical systems can be referred to as dioptric, catoptric, and catadioptric, respectively. Other types of refractive, reflective, diffractive, holographic and other optical elements can be used as may be convenient. 
     “Rotation,” unless otherwise specified, refers to rotation about any axis that provides the desired result. Many of the embodiments described below utilize an optical element that is rotated about the optical axis. Rotation about an axis that is perpendicular to the optical axis is also called “tilt.” Rotation about the remaining orthogonal axis is also called “tip.” 
     In typical embodiments described below, a rotatable wedge element is situated at a suitable location in a beam path. The wedge element typically deflects the beam from its propagation axis typically by less than about 1 mrad, 2 mrad, 5 mrad, 10 mrad, 50 mrad, 100 mrad, or 500 mrad. Rotating the wedge element about the beam propagation axis can then sweep the beam along a closed path such as a circle or ellipse. In other examples, a scan path can be a polygon, or portions of such closed curves. Alternatively, a beam scan can be a raster scan, a vector scan, a w-pattern, and scanning can be periodic or aperiodic. The examples below are provided with respect to a laser radar that is configured to, for example, provide an estimate of surface topography based on portions of an optical beam directed to a surface that are returned to a receiver. The disclosed method and apparatus can also be incorporated into laser tracker systems. 
     Some described embodiments include a corner cube used as part of a focus system. For convenient illustration, such corner cubes are shown in some figures as two reflectors having reflective surfaces at 90° with respect to each other. 
     A representative embodiment of a laser radar  100  (as an exemplary optical system) is illustrated in  FIG. 1 . A transmit/receive system  102  produces one or more optical beams that interact with a beam-forming unit  106  and with a beam-scan unit (“scan optics”)  110 . The beam-forming unit  106  also generally serves as a beam-collection unit. The beam-forming unit  106  produces an optical beam  108  that is directed to the beam-scan unit  110 . The optical beam typically includes a measurement beam at a first wavelength and an alignment beam at a second, visible, wavelength. As shown in  FIG. 1 , the optical beam  108  is directed along an axis  112  (called a “nominal propagation axis”) to a target  114  in the absence of being deflected by the beam-scan unit  110 . Typically, the beam-scan unit  110  is configured to produce an angular deflection of the optical beam  108  so that the optical beam assumes a circular or other scan path  116  relative to the nominal propagation axis  112 . 
     Scattered, reflected, or other portions  117  of the optical beam  108  (at least of the measurement beam) return to the transmit/receive system  102  via the beam-scan unit  110  and the beam-forming unit  106 . Detected signals based on the returned beam portions are routed to a signal processor  118 , which produces measurements of a target surface that can be provided to a display  120 . In some examples, the detected signals are processed to provide target-surface assessments or determine target-surface characteristics without needing to produce a display image. The beam-scan unit  110  and the signal processor  118  are generally coupled to a control interface  122  so that beam scanning can be correlated with corresponding detection signals. The control interface  122  can also be configured to permit a user to input selected scan ranges, scan rates, surface data assessments, or other measurement configurations. 
     With reference to  FIG. 2 , a second embodiment of an optical system  200  is shown that can be used as a laser radar system. The system of this embodiment comprises a module  202  including a transmit/receive system  204 , a beam-forming unit  206 , a control interface  208 , and a signal processor  210 , all secured to a common support  212 . A secondary beam-scan unit (“secondary scan optics”)  230  is also secured to the common support  212 . The optical system  200  can be secured to one or more rotational stages  223  such as a gimbal system. An optical beam (or combination of measurement and alignment beams) can be directed (as controlled by the primary beam-scan unit  224 ; denoted “scan primary ctrl”) along a nominal propagation axis  232  toward a target  220 . The combined measurement and alignment beams can be scanned over the target  220  using the stage  223 , but the relatively large mass of the stage and anything mounted to it generally limits scan speeds. The system  200  also includes the secondary beam-scan unit (“secondary scan optics”)  230  that receive the beam(s) from the module  202  and scans the beam(s) relative to the nominal propagation axis  232 . 
     It will be understood that  FIG. 2  depicts an embodiment that is not intended to be limiting. For example, it is not necessary that the control interface  208 , the signal processor  210 , the beam-forming unit  206 , or even the transmit/receive system  204 , in any combination, be situated on or in the laser radar module  202 . One or more of these assemblies can be provided, for example, as respective stationary (or independently placeable) unit(s). In addition, it is not necessary that any of the control interface  208 , the signal processor  210 , the beam-forming unit  206 , or the transmit/receive system  204  be movable at all. Optical interconnections and electrical interconnections among the assemblies can be readily made using flexible optical cable and flexible electrical cable as needed. Similarly, electrical and optical interconnections between the secondary scan optics  230  and any other unit of the system  200  can be made using flexible fiber-optic cables, for example. 
     A third representative embodiment of an exemplary optical system, configured as a laser radar system, is illustrated in  FIG. 3 . The beam-forming unit comprises an optical fiber  302  including an emitter surface  304  that produces an optical beam  306  directed to a corner cube  308  (as an exemplary reflective optical element of the beam-forming unit). The optical fiber  302  is coupled by a beam splitter  305  to a transmit (“TX”) system  303 . The transmit system  303  includes one or more lasers or other suitable light sources (not shown in  FIG. 3 ). It is generally convenient to select the optical fiber  302  and the measurement-beam wavelength so that the optical beam emitted by the optical fiber  302  propagates in a lowest-order mode of the fiber; but, higher order modes can alternatively be used. An alignment beam can be similarly produced and selected by these components. In some examples, the fiber  302  is selected to be single mode at about 1550 nm so that a 1550-nm measurement beam propagates in a single, lowest-order mode and the visible alignment beam propagates in only a few fiber modes. A receiver (“RX”) system  307  is coupled by the beam splitter  305  to the optical fiber  302 . The beam splitter is shown for convenience as a cubic beam splitter; but, it will be understood that other arrangements including fiber couplers can be used instead. 
     The optical beam  306  emitted from the optical fiber  302  is typically not collimated, propagating with an angular diameter of about two times the numerical aperture of the optical fiber. The corner cube  308  directs the emitted beam to a reflector  310 , from which the beam is reflected back through the corner cube along a nominal propagation axis  312  to a beam-forming lens  314 . The corner cube  308  is secured to a translation stage  318  that is movable under the direction of a focus controller  320 . Adjustable displacement of the corner cube  308  along the axis  312  permits focusing of the optical beam on the target. 
     The embodiment of  FIG. 3  also includes a beam-scan unit comprising a wedge prism  324  that is secured to a rotational stage  325  and situated to receive the optical beam from the lens  314 . The prism  324  deflects the optical beam along a scan axis  328  relative to the nominal propagation axis  312 . The orientation of the scan axis  328  can be varied based on the rotational angle of the prism  324  relative to the nominal propagation axis  312 . In some examples, the prism  324  is situated at a so-called minimum deviation angle, wherein the prism wedge angle β can be selected to produce a suitable deflection. The rotational stage  325  is situated and configured so that the prism  324  can be rotated about the nominal propagation axis  312  while the rotational axis of the rotation stage  325  is tilted relative to the axis  312 . An encoder  331  can be provided for measuring rotation angles. 
     To achieve scanning motion of the optical beam(s), the entire optical system of  FIG. 3  could be moved in a scanning manner (an electromechanical system for producing such scanning is not shown in  FIG. 3 , but see the discussion above regarding  FIG. 2 ). Having to move the entire system to produce scanning motion of the beam(s) limits the achievable scanning rate and scanning accuracy and precision due to the system&#39;s relatively high mass. Instead, in this embodiment, scanning motion of the beam is achieved by rotating the wedge prism  324  relative to the rest of the system, which allows production of correspondingly higher scan rates. 
     Whereas the wedge prism  324  can be controlled so as to be rotated at a fixed or variable frequency, the wedge prism  324  can also be controlled to achieve scanning over fixed or variable segments of an arc. Portions of the optical beam received at the receive system  307  can be associated with a particular portion of a target based on a synchronization signal supplied by a rotation controller  330 . Alternatively, an image processor that is coupled to receive and process detection signal data from the receive system  307  can provide synchronization signals that are received by the rotation controller  330  and used to select wedge-prism rotations. 
     As shown in  FIG. 3 , rotation of the wedge prism  324  produces corresponding beam rotation  331  about the nominal propagation axis  312 . Alternatively, other optical elements can be used to produce similar rotations, such as (but not limited to) ruled diffraction gratings, holographic gratings, achromatic prisms, and other elements. In addition, one more additional wedge prisms can be situated so as to rotate or deflect the optical beam further. These additional prisms can have a common wedge angle or different respective wedge angles, and an image processor can be configured to associate detected optical radiation with corresponding locations in a region of interest based on the orientation of the prisms and their respective prism angles. 
     In an alternative configuration, the wedge prism  324  is replaced with a mirror that is mounted to the rotation stage  325  so as to receive light flux from the lens  314  and reflect the light flux downstream toward a target surface. In this alternative configuration, rotation of the mirror by the rotation stage  325  produces a corresponding scanning motion  331  of the beam. Hence, in the secondary scan system of this alternative configuration, the rotatable wedge prism  324  is replaced by a rotatable mirror, but the other components are the same as shown in  FIG. 3 . 
     Referring now to  FIG. 4A , another embodiment of a secondary scan system  400  comprises a first prism  402  and a second prism  404  having respective prism wedge angles α, β. The prisms  402 ,  404  are secured to respective rotational stages  405 ,  407  that are individually rotatable under the control of “scan ctrl”  410 . In some orientations, deflections produced by the prisms  402 ,  404  are additive along a single direction, while in other orientations, the scan deflections are along orthogonal or non-parallel axes so that more complex scan patterns and larger scan patterns can be produced. If the prisms  402 ,  404  are selected so that the prism angles α=β, then the prisms  402 ,  404  can be oriented to produce substantially zero deflection. The first prism  402  and the second prism  404  can be collectively rotated about a common axis or rotated about different respective axes to produce varying scan patterns. For example, the rotational stages  405 ,  407  can be situated to provide associated selected scan angles, and the rotational stages  405 ,  407  can be independently rotatable. 
     It will be understood that one or both prisms  402 ,  404  can be replaced with a respective mirror mounted to a respective rotational stage and rotated to impart a desired scanning motion to the beam propagating to a target or the like. 
       FIG. 4B  illustrates an embodiment of a wedge-prism assembly  420  that comprises a wedge prism  422  secured to a rotational stage  424 . A scan controller (“scan ctrl”)  426  is configured to adjust the rotational angle δ of the rotational stage  424  as required to produce a desired scanning motion of an optical beam  428  passing through the assembly. The wedge prism  422  is situated so that a deflection angle δ of the input optical beam  428  can be obtained from n prism =sin(δ+β)/2/sin β/2, wherein β is wedge angle and n prism  is index of refraction of the wedge prism  422 . At the angle of minimum deviation, the input optical beam  428  is refracted so as to propagate perpendicularly to a bisector  430  of the wedge angle β. One or more rotary encoders such as encoder  431  can be coupled to the rotational stage  424  to provide measurements of the current angle of rotation. The measurement data are provided to the scan controller  426  so that beam scanning can be controlled and/or the rotation angle measured. Again, it will be understood that the wedge prism  422  can be replaced with a mirror that is rotatably mounted and adjustable in a similar manner. 
       FIG. 4C  illustrates a portion of a wedge prism assembly  440  configured to scan an input optical beam  438  relative to an axis  439  by tilting a wedge prism  442  about an axis  443 . The wedge prism is adjustably mounted to produce tilting of the prism apex as shown at  445 . In this example, the input optical beam  428  is generally not incident to the wedge prism  442  at the minimum deviation angle. Again, it will be understood that the wedge prism  442  can be replaced with a mirror. 
     A representative embodiment of a measurement method is illustrated in  FIG. 5 . At  502 , an optical beam is scanned along an arc or other scan path using, for example, a rotating wedge element. At  504 , returned portions of the optical beam are detected, and magnitudes or other characteristics of the returned beam are estimated. At  506 , the detected portions are evaluated to determine possible surface features. In some examples, spherical or circular target features are of interest, and a center location of a target circle or sphere can be estimated based on signal characteristics. If beam centration is determined to be of interest at  508 , then the beam position is adjusted at  510 . Typically, beam adjustment is accomplished by movement of components other than a rotating wedge, such as by rotating the laser radar optical system on one or more stages; but, a wedge can be used if desired. After beam adjustment, beam scanning continues at  502 . 
     Measurements produced by the method  500  can be used to produce an average measurement over a small patch of a target surface. Alternatively, the measurement data can be analyzed to determine surface orientation at a measurement location. By monitoring return-signal intensity around the circular scan, deviations from a center location or a particular location on the target can be estimated so that the measurement beam can be maintained in alignment with a specific target-surface location. In other examples, wedge scanning can be used to increase measurement quality, accuracy, or rate, or to track particular surface features. In some examples, wedge-based scanning can be used exclusively. 
     In typical applications, a secondary beam scanner is used to track a target feature. Based on the beam-displacement needed, a primary beam scanner can be adjusted so that beam scanning remains within a preferred range of primary scan angles of the scanner, typically near a center of a primary scanner scan pattern or scan range. 
     In the embodiments of laser radar systems disclosed above, scattered, reflected, or other portions of a scanned optical beam are returned to a transmit/receive system. Detected signals based on the returned beam portions are coupled to a signal processor and used to form a target-surface image or contour map. Corresponding data can be provided to a display. In some examples, the detected signals are processed to provide target-surface assessments without producing a displayed image. The scanning wedge (and/or scanning mirror) and the signal processor are generally coupled to a control interface so that beam scanning can be correlated with a corresponding detection signal. The control interface can also be configured to permit user inputs to select scan ranges, scan rates, surface data assessments, or other measurement configurations. Typically, wedge rotations and/or scanned beam locations can be monitored during a scan using one or more encoders or other monitoring systems, but these are not shown in some figures. In some examples, detection of beam deflection or wedge rotation is not needed due to stable, open-loop scan performance and/or calibration that can be performed at occasional intervals. However, real-time tracking of beam scan and the associated scan elements can be advantageous. 
     Some features of the embodiments discussed allow beam steering without using the rotary axes of a laser radar. Since the steering element (a wedge and/or mirror) can be small and low in mass, it can be moved more easily and quickly than otherwise achieved by rotation about main rotary axes, and so tends to allow quicker scans in the vicinity of a given measurement point. This could be used for producing spiral or w-scans, for example. In addition, different measuring strategies can be implemented such as, for example, averaging a number of points around a selected measurement point to get a better estimated value, or determining surface orientations on a small patch. Monitoring the intensity of a return signal as a beam is moved can give an indication of centering of a tooling ball relative to a measurement beam. These features may increase measurement quality, accuracy, or rate, and can be used for a tracking function, so that a laser radar system as disclosed herein can mimic at least some laser-tracker functionality. 
     An embodiment of a laser tracking or laser radar system  600  (as an exemplary optical system) that includes a primary beam scanner  601  and a secondary scanner  611  is illustrated in  FIG. 6 . The primary scanner  601  is mechanically coupled to an optical system  602  that is configured to move an optical beam(s) introduced by an optical fiber  603 . The optical system  602  comprises a corner cube  608  situated to direct the beam emitted from the fiber  603  to a reflector  610 . The reflector  610  reflects the beam back through the corner cube  608 , from which the beam propagates along an axis  612  to a beam-forming lens  614 . The corner cube  608  is coupled to a translation stage  618  that is movable under the direction of a focus controller (“focus adjust”)  620 . Displacing the corner cube  608  along the axis  612  focuses the optical beam on a target, for example. Alternatively to using a corner cube, focus adjustments can be made using other optical and/or opto-mechanical devices. 
     In this embodiment the optical fiber  603  is coupled to a transmit system (“TX system”)  609  via a beam splitter  605 . The transmit system  609  typically includes one or more lasers or other light-beam sources (not shown) that produce optical beams. A receiver system (“RX system”)  607  is also coupled to the optical fiber  603  via the beam splitter  605 . The beam splitter shown in  FIG. 6  is shown as a cubic beam splitter for convenience; alternatively, other arrangements including use of fiber couplers can be used. 
     The system  600  is depicted in  FIG. 6  as having a bend  624  in the axis  612  between the lens  614  and the secondary scanner  611  to indicate that the axis  612  (indeed, substantially any optical axis) is not necessarily linear over its entire length. Rather, the axis can be bent by encountering a change in reflective or refractive surface using, for example, a mirror or prism (not shown) as desired or required. Alternatively, all or a portion of the propagation pathway of a beam of light can be provided by an optical fiber, for example, by which bends and curves in the axis can be conveniently made. (Note the optical fiber  603  coupled to the beam splitter  605 .) In  FIG. 6 , the bend  624  is also made to accommodate the manner in which the secondary scanner  611  is depicted in the figure. 
     The secondary beam scanner  611  is situated along the axis  612  to receive the beam from the lens  614  for scanning. The secondary beam scanner  611  includes a reflective surface  628  (shown in  FIG. 6  as a mirror surface). The reflective surface  628  is coupled to a tiltable mount  632 , having a tilting axis  641 , being tiltable via an actuator  627 , and being controlled by a “rotation adjust” controller  630 . The axis  641  is tilted with respect to an axis  642  that is perpendicular to the reflective surface  628  or oriented relative to the reflective surface by an angle α, such that the axes  641 ,  642  are not parallel to each other. Smaller values of α produce smaller beam deviations in response to rotations. The reflective surface  628  deflects the optical beam based on the rotational angle of the reflective surface  628  about the axis  641 . The optical beam reflected from the rotating reflective surface  628  propagates along scan axes  630  relative to the nominal propagation axis  634 . 
     While the reflective surface  628  can be controlled so as to be rotated at a fixed or variable frequency, the surface can also be configured to provide scans over arcs, line segments, or closed curves such as ellipses, circles, and polygons, for example. Portions of the optical beam received at the receiver system  607  can be associated with a particular portion of a target based on a synchronization signal supplied by a rotation-adjust controller  630 . Alternatively, an image processor that is coupled to receive and process detection signal data from the receive system  607  can provide synchronization signals that are received by the rotation-adjust controller  630  and used to select rotations. One or more reflective surfaces can be provided based on prism surfaces, mirror surfaces, or other reflective surfaces. 
       FIG. 7  illustrates a portion of an embodiment of an optical system  700  that is configured to direct an optical beam  703  along a nominal propagation axis  712 . The optical beam  703  is incident to a corner cube  708  and to a return reflector  710 , and is focused by an objective lens  714  onto a target. The return reflector  710  is secured to a rotatable stage  716  that is configured to rotate about an axis  724 . The reflector  710  has a surface mirror  720  that is tilted at an angle α with respect to the axis  724 . Rotation of the reflector  710  thus causes beam scanning. In this embodiment the tilt need not be constant; the reflector  710  can readily be mounted to the stage  716  in a manner allowing the tilt to be adjusted. In addition, the reflector  710  can be readily made to simply tip and tilt about respective axes that are orthogonal to the axis  712 . 
     Turning now to  FIG. 8A , an embodiment of a secondary scanning system  800  includes a rotatable beam deflector  802  that is situated on a shaft  804  that rotates the deflector about an axis  806 . An optical flux  803  to be formed into a beam and scanned is directed along a nominal propagation axis  812  to a corner cube  808  or other reflector, and directed through the beam deflector  802  to a return mirror  820 . The return mirror  820  directs the optical flux along the axis  812 , but at a fixed or variable scan angle, to a lens  814  to produce a beam that is directed to and scannable on a target. The beam deflector  802  is transparent to the optical flux  803  and is sufficiently large to accommodate substantially the entire beam width associated with the optical flux. The beam deflector  802  can be rotated continuously at a fixed or variable rate, or stepped to a particular location to produce a selected deflection. One or more encoders can be provided for measuring rotation, and two or more beam deflectors can be configured to rotate at different rates about the same or different axes, thereby producing deflections that differ in magnitude and/or direction. 
     In one example, the beam deflector can be a transparent disc having a variable prism-wedge angle as shown in  FIG. 8B . The prism-wedge angle α can be any of various functions of an angular coordinate θ, i.e., α=α(θ), such as a linear, non-linear, or periodic function of θ. The prism wedge can be directed along a radius, directed orthogonally to a radius, or in other directions. A periodic variation in wedge angle can be used so that a scan pattern repeats more than once during a single rotation of the beam deflector  802 . For example, a selected variation in wedge angle can occur once, twice, or N times per rotation, wherein N is a positive number, or conveniently, an integer. A ring-shaped beam deflector such as the deflector  802  can have a stepped or continuously varying wedge angle, can have a flat section without a wedge, or can have different wedges defined by a front surface and a rear surface.  FIG. 8C  is a sectional view of a representative implementation of the beam deflector  802 . As shown in  FIG. 8C , a wedge angle α is a function of an angular coordinate θ. 
     In an alternative configuration to that shown in  FIG. 8A , it is possible to produce a beam scan using a plane-parallel plate and tilting the plate about an axis that is perpendicular to the axis  806 . In such a configuration the plane-parallel plate effectively shifts the source relative to the lens  814  and produces a shift of the focus spot on the target. A plane-parallel plate can be tilted about two axes orthogonal to the axis  806  to produce a scan in two dimensions. Alternatively, the plate can be tilted on one axis that is perpendicular to the axis  806  and then rotated about the axis  806 . This alternative approach can be convenient for producing circular or spiral scans, for example. A desirable aspect of this approach is that it is easy to nullify the scanning motion by positioning the plate perpendicular to the beam, in contrast to having to use two prisms to produce no net beam deviation (see  FIG. 4A ). 
       FIG. 9A  illustrates a portion of a laser tracker or laser radar system that includes a variable wedge beam deflector  906  that is coupled to a linear actuator  904 . The linear actuator translates the beam deflector along an axis  908 . An input beam  912  is directed by a corner cube  910  or other reflector to the beam deflector  906  and to a return reflector  920 . The beam deflector  906  has a variable thickness along  908  as defined by a surface  903 , and translation of the beam deflector  906  scans the beam, formed by a lens  924 , across a target.  FIG. 9B  is a representative sectional view of the beam deflector  906 . The beam deflector  906  has wedge regions  903 A- 903 C corresponding to different respective wedge angles. Fewer or more stepped regions can be used, or the wedge angle can vary continuously. 
       FIG. 10  illustrates a portion of an embodiment of a laser tracking or laser radar system that comprises a transmitter (“TX system”)  1003  that directs an optical flux through a beam splitter  1005  to an optical fiber section  1008 . A beam-deflection system includes a rotation controller (“rotation adjust”)  1010  coupled to a beam deflector  1012  that is rotatable about an axis  1013 . The beam deflector  1012  is configured to receive the optical flux from the optical fiber section  1008  and to transmit the flux to a lens  1014 . Absent a variable deflection imposed by the beam deflector  1012 , the flux is focused by the lens  1014  at or near a reflective surface  1016  and propagates along an axis  1004  to a corner cube  1020  and a return reflector  1022 . The flux is then directed back to the corner cube  1020  to an objective lens  1021  that focuses the flux on a target. Deviations or deflections of the flux (e.g.,  1018 ) by the beam deflector  1012  cause corresponding scanning of the beam produced by the lens  1021 . The corner cube  1020  is coupled to a movable stage  1009  under the control of a focus adjust controller  1007 . Also shown is the receiver (“RX system”)  1003 . 
     In an alternative configuration to that shown in  FIG. 10 , it is possible to produce a beam scan using a plane-parallel plate and tilting the plate about an axis that is perpendicular to the axis  1013 . In such a configuration the plane-parallel plate effectively shifts the source relative to the lens  1022  and produces a shift of the focus spot on the target. A plane-parallel plate can be tilted about two axes orthogonal to the axis  1013  to produce a scan in two dimensions. Alternatively, the plate can be tilted on one axis that is perpendicular to the axis  1013  and then rotated about the axis  1013 . This alternative approach can be convenient for producing circular or spiral scans, for example. A desirable aspect of this approach is that it is easy to nullify the scanning motion by positioning the plate perpendicular to the beam, in contrast to having to use two prisms to produce no net beam deviation (see  FIG. 4A ). 
       FIG. 11  illustrates an embodiment of a beam scanner  1100  that comprises a prism  1102  situated on or in a rotational stage  1104  and configured to receive an optical beam  1101  from a lens  1106 . The optical beam  1101  is refracted by the prism  1102  so as to propagate along an axis  1110  that is tilted with respect to a nominal propagation (non-deflected) axis  1112 , and to produce scanned beams such as beams  1116 ,  1118 . A rotation controller (“rotation adjust”)  1120  provides selected beam deflections based on the orientation of the prism  1102 . 
       FIG. 12  illustrates an embodiment of a beam tracking or laser radar system  1200  that comprises a transmitter  1203  that couples a laser beam to a fiber  1208 . The beam from the fiber  1208  is directed along an axis  1206  by a lens  1210  and a reflector  1214 . The beam is reflected by a corner cube  1209  to a tiltable mirror  1216  coupled to a stage  1218 . A rotation controller (“rotation adjust”)  1220  adjusts the tilt angle of the prism  1216 , thereby producing a selected change in the axis  1206  to a deflection axis  1224 . The resulting deflected beam can be scanned by making appropriate changes in the deflection angle by tilting the mirror  1216 . The mirror  1216  can be both tilted and tipped to produce beam scanning in two axes. A beam, produced by the transmitting (“TX”) system  1203 , passes through a lens  1210  and reflects from a beam splitter  1214  to the corner cube  1209 . The corner cube is movable under control by a focus adjust. Also shown is a receiving (“RX”) system  1204 . 
       FIG. 13  illustrates an embodiment of a beam deflector that is similar to the embodiment of  FIG. 12 . However, in  FIG. 13 , a tiltable prism  1302  is used to reflect the incident beam from a rear surface  1304  thereof, not from a front surface  1217  of a mirror as shown in  FIG. 12 . 
     With reference to  FIG. 14 , an embodiment is shown in which the reflective prism  1216  of the embodiment of  FIG. 12  is replaced with another prism  1416  and a reflector  1419 . The prism  1416  is secured to a rotational stage  1418  controlled by a rotational controller (“rotation adjust”)  1420 . An optical flux that is incident to the prism  1416  along the axis  1412  is deflected or scanned to as to propagate along an axis  1422 . A lens  1430  receives the deflected beam and directs it to a target. Beam-scan angles are selected based on the tilt angle of the prism  1416 . Also shown are a transmitting (“TX”) system and a receiving (“RX”) system. 
     For convenience, the examples described above generally include transparent or reflective prisms with plane surfaces, continuously curved surfaces, or stepped surfaces. Other beam deflectors that can be used include Fresnel lenses, diffraction gratings, holographic optical elements, or other diffractive, refractive, reflective, continuously varying, or stepped optical elements. 
       FIG. 15  illustrates a representative method for tracking a tooling ball secured to a substrate or target. One or more tooling balls can be secured to a target to provide reference points for coordinate determinations. A tooling ball generally includes a reflective ball-shaped surface that provides ample reflection of an interrogation beam in a laser-based measurement apparatus such as a laser radar. As shown in  FIG. 15 , at  1502  a tooling ball location is identified and recorded based on returned portions of a scanned interrogation optical beam. The optical beam can be scanned in a variety of patterns such as circles, spirals, w&#39;s, or zig-zags so as to track a tooling ball. At  1504 , the identified location is evaluated to determine a tooling ball position with respect to a primary scan. The primary scan is adjusted at  1506  so that the tooling ball is located at a preferred location relative to the primary scan. Typically, the primary scan is adjusted so that the tooling ball location is approximately centered within a primary scan range. At  1508 , a determination is made of whether to produce additional scanning. A secondary scanner can be used to track a tooling ball, and the primary scanner can be adjusted based on the secondary scanner so that the tooling ball remains centered or located at a preferred location in the optical beam scan. 
       FIG. 16  illustrates an embodiment of a manufacturing system  1600  suitable for producing one or more components of a ship, airplane, or parts of other systems or apparatus, and for evaluating and reprocessing such manufactured components. The system  1600  typically includes a shape- or profile-measurement system  1605  such as the laser radar  100  discussed above. The manufacturing system  1600  also includes a design system  1610 , a shaping system  1620 , a controller  1630 , and a repair system  1640 . The controller  1630  includes coordinate storage  1631  configured to store measured and design coordinates or other characteristics of one or more manufactured structures as designed and/or measured. The coordinate storage  1631  is generally a computer-readable medium such as a hard disk, a random access memory, or other memory device. Typically, the design system  1610 , the shaping system  1620 , the shape-measurement system  1605 , and the repair system  1640  communicate with each other via a communication bus  1615  using a network protocol. 
     The system  1610  is configured to create design information corresponding to shape, coordinates, dimensions, or other features of a structure to be manufactured, and to communicate the created design information to the shaping system  1620 . The system  1610  can also communicate design information to the coordinate storage  1631  of the controller  1630  for storage. Design information typically includes information indicating the coordinates of some or all features of a structure to be produced. 
     The shaping system  1620  is configured to produce a structure based on the design information provided by the design system  1610 . The shaping processes provided by the shaping system  1620  can include casting, forging, cutting, or other process. The shape-measurement system  1605  is configured to measure the coordinates of one or more features of the manufactured structure and to communicate, to the controller  1630 , information indicating measured coordinates or other information related to structure shape. 
     A manufacture inspector  1632  of the controller  1630  is configured to obtain design information from the coordinate storage  1631 , and to compare information such as coordinates or other shape information received from a profile-measuring apparatus such as the apparatus  100  of  FIG. 1  with design information read out from the coordinate storage  1631 . The manufacture inspector  1632  is generally provided as a processor and a series of computer-executable instructions that are stored in a tangible computer-readable medium such as a random access memory, a flash drive, a hard disk, or other memory device. Based on the comparison of design and actual structure data, the manufacture inspector  1632  can determine whether or not the manufacture structure is shaped in accordance with the design information, generally based on one or more design tolerances that can also be stored in the coordinate storage  1631 . In other words, the manufacture inspector  1632  can determine whether or not the manufactured structure is defective or non-defective. When the structure is not shaped in accordance with the design information (and is defective), then the manufacture inspector  1632  determines whether or not the structure is repairable. If the structure is repairable, then the manufacture inspector  1632  can identify defective portions of the manufactured structure and provide suitable coordinates or other repair data. The manufacture inspector  1632  is configured to produce one or more repair instructions or repair data and to forward repair instructions and repair data to the repair system  1640 . Such repair data can include locations requiring repair, the extent of re-shaping required, or other repair data. The repair system  1640  is configured to process defective portions of the manufactured structure based on the repair data. 
       FIG. 17  is a flowchart of a representative embodiment of a manufacturing method  1700  that can incorporate manufacturing systems such as illustrated in  FIG. 16 . At  1702 , design information is obtained or created corresponding to the shape of a structure to be manufactured. At  1704 , the structure is manufactured or “shaped” based on the design information. At  1706 , coordinates, dimensions, or other features of the manufactured structure are measured using a profile-measurement system, such as any of the laser radar systems described above, to obtain shape information corresponding to the structure as manufactured. Typically, profile measurement is accomplished with a fine scan and a coarse scan of a laser beam. At  1708 , the manufactured structure is inspected based on a comparison of actual and design dimensions, coordinates, manufacturing tolerances, or other structure parameters. At  1710 , if the manufactured structure is determined to be non-defective, the manufactured part is accepted and processing ends at  1714 . If the manufactured part is determined to be defective at  1710  by, for example, the manufacture inspector  1632  of the controller  1630  as shown in  FIG. 16 , then at  1712  a determination is made of whether the manufactured part is repairable. If repairable, the manufactured part is reprocessed or repaired at  1716 , and then measured, inspected, and reevaluated at  1706 ,  1708 ,  1710 , respectively. If the manufactured part is determined to be unrepairable at  1712 , the process ends at  1714 . 
     According to the embodiment of  FIG. 17 , a manufactured structure can be evaluated using a profile-measurement system to measure or assess coordinates or other features of a manufactured structure. Thus, the structure can be evaluated to determine whether the structure is defective or not. If the structure is determined to be defective but repairable or reprocessable, a reprocessing process can be performed. By repeating measurement, inspection, and evaluation, defective parts can be readily identified and reprocessed, while structures that are defective and non-repairable can be set aside or discarded. The particular systems and methods of  FIGS. 16-17  are exemplary only, and other arrangements alternatively can be used. 
     In the embodiment of  FIG. 17 , the manufacturing system  1700  can include a profile-measurement system comprising a laser radar  100 , a design system  910 , a shaping system  920 , a controller  930  configured to determine whether a structure is acceptable (inspection apparatus), and a repair system  940 . However, other systems and methods can be used, and the exemplary embodiments of  FIGS. 16 and 17  are provided for convenient illustration and should not be regarded as limiting the scope of the this disclosure. We claim all that is encompassed by the appended claims. 
     Whereas the invention has been described in the context of multiple representative embodiments, it will be understood that it is not limited to those embodiments. On the contrary, it is intended to cover all modifications, alternatives, and equivalents as may be including within the spirit and scope of the invention, as defined by the appended claims.