WO2016084065A1

WO2016084065A1 - 3d scanners for simultaneous acquisition of multiple 3d data sets of 3d object

Info

Publication number: WO2016084065A1
Application number: PCT/IL2015/051124
Authority: WO
Inventors: Uri Neta
Original assignee: A. B. Imaging Solutions Ltd
Priority date: 2014-11-27
Filing date: 2015-11-22
Publication date: 2016-06-02
Also published as: IL235950A0

Abstract

A 3D scanner has an acquisition module and a mirror module. The mirror module includes multiple mirrors angled differently towards a scanned object for simultaneously reflecting each light from at least partially different regions of the object towards the acquisition module. The light received via each mirror at the acquisition module is processed to derive a 3D data set of the respective region from which the light is received.

Description

3D DATA SETS OF 3D OBJECT

Field of the Invention

The invention relates to non-contact 3D scanners for generating 3D surface files modelling 3D surfaces of 3D objects.

Background of the Invention

Commercially available 3D scanners for scamiing 3D objects are employed in a wide range of industrial, medical and general purpose modelling applications. 3D scanners include acquisition modules employing different 3D scanning technologies including inter aLIa stereoscopic scanning, pattern projection, confocal imaging, moving optics system with very small depth of focus, and others. 3D scanners acquire a series of so-called 3D data sets which include either a single 2D image with depth information or a single 2D matrix with depth information or a single stereoscopic 2D image modeling the geometry of the scanned 3D object. 3D scanners may include a 3D surface processing module for processing in some cases 3D data sets to generate 3D point clouds and possibly also to statistically stitch 3D point clouds in an iterative process commonly called alignment or registration to generate a 3D surface file modelling a scanned 3D surface of a 3D object.

Some 3D scanning applications require a 3D object to be scanned from a single direction only. Other 3D scanning applications require a 3D object to be scanned from multiple directions. 3D scanners can include either a stationary acquisition module or a movable acquisition module. Moving acquisition modules can be either mounted on an articulated arm or handheld.

Some 3D scanners include a single flat mirror in an acquisition module's field of acquisition for reflecting a reflection of a 3D object theretowards for assisting scanning of 3D objects with limited access thereto for scanning purposes. Exemplary such 3D scanners include 3D intraoral scanners for enabling insertion of a handheld probe into a patient's mouth for scanning his dentition from inside his mouth.

Scanners possibly used for intra oral scanning may be found utilizing projection of patterned or structured light to obtain surface information for structures of various types. A pattern for example of lines may be projected towards a surface of an object and a captured image of the object may then be analysed to determine a 3D data set of the surface information.

Laser scanners may also be found creating such 3D data set information of an object, for example, through use of triangulation. A laser dot or line projected onto an object may be picked up by a sensor (typically an image sensor) and this data can be further processed to measure the distance to the surface to thereby create the 3D data set.

Summary of the Invention

The present invention is directed to non-contact 3D scanners for simultaneous acquisition of 3D data sets of a scanned 3D surface of a 3D object for generating a 3D surface file modelling the scanned 3D surface of the 3D object. The 3D scanners of the present invention include a conventional acquisition module capable of acquiring a single 3D data set of a scanned 3D surface of a 3D object at an instant in time at a given position of the acquisition module relative to the 3D object. The 3D scanners of the present invention additionally include a mirror module deployed in an acquisition module's field of acquisition and including a multitude of differently angled mirrors for simultaneously reflecting a multitude of differently angled reflections of a 3D object towards the acquisition module thereby enabling the acquisition module (or scanner possibly a processing module of the scanner) to simultaneously acquire (and process) a multitude of different 3D data sets of the scanned 3D surface of the 3D object at an instant in time for a given position of the acquisition module relative to a 3D object.

The simultaneous acquisition and/or processing of a multitude of different 3D data sets at an instant in time for a given position of an acquisition module relative to a 3D object reduces scanning time required to generate a 3D surface file and increases accuracy and/or scanned coverage of a 3D object compared to conventional 3D scanners. Reduced scanning time is particularly beneficial for some scanning applications, for example, intraoral scanning to minimize patient discomfort during scanning of his dentition. Moreover, simultaneously acquired 3D data sets can be beneficially geometrically stitched as opposed to being statistically stitched by virtue of the known geometrical arrangement of the multiple mirrors of a mirror module which is both more accurate and less time consuming than statistical stitching. The present invention is technologically agnostic in the sense it can be implemented with the different aforementioned scanning technologies for scanning a 3D surface of a 3D object.

3D scanners of the present invention can optionally include interchangeable mirror modules such that the same acquisition module can be used with different mirror modules depending on a scamiing application at hand. For example, different mirror modules are required for scanning of industrial parts with surface features only compared to industrial parts with blind bores. Mirror modules can mclude two or more flat mirrors, or two or more curved mirrors, or a combination of flat and curved mirrors. A reflection pair of a mirror module can optionally include an overlap region or be spaced apart reflections with no overlap region. The 3D scanners of the present invention can optionally mclude an illumination module for illuminating a 3D object with visible light, infrared illumination, etc.

The 3D scanners of the present invention can be implemented as handheld scanners, for example, for 3D intraoral scanning purposes. Alternatively, the 3D scanners of the present invention can be implemented as 3D scanning systems for quality control purposes. Such 3D scanning systems can include two or more acquisition modules each with its associated mirror module for scanning a series of 3D objects and a quality control module for determining whether a 3D object satisfies a list of predetermined requirements and issuing an alert on detection of a 3D object which does not satisfy same. Brief Description of Drawings

In order to understand the invention and to see how it can be carried out in practice, preferred embodiments will now be described, by way of non- limiting examples only, with reference to the accompanying drawings in which similar parts are likewise numbered, and in wiiich:

Fig. 1 is a combined pictorial view and block diagram of a conventional 3D intraoral scanner for scanning a dentition to generate a 3D digital impression modelling the dentition;

Fig. 2 is a schematic diagram of the 3D intraoral scanner scanning a 3D object and the resulting acquired 3D data set;

Fig. 3 is a combined pictorial view and block diagram of a 3D intraoral scanner in accordance with an embodiment of the present invention for scanning a dentition to generate a 3D digital impression modelling the dentition;

Fig. 4 is a schematic diagram of an embodiment of a mirror module including a pair of flat mirrors for reflecting a reflection pair including an overlap region scanning the same 3D object and the resulting processed two overlapping 3D data sets;

Fig. 5 is a schematic diagram of an alternative embodiment of a mirror module including a pair of flat mirrors for reflecting a reflection pair of spaced apart reflections without an overlap region scanning the same 3D object and the acquired and/or processed 3D data sets;

Fig. 6 is a schematic diagram of a further alternative embodiment of a mirror module including a pair of flat mirrors deployed at different orientations in the field of acquisition without an overlap region scanning the same 3D object and the acquired and/or processed 3D data sets;

Fig. 7 is a schematic diagram of a yet further alternative embodiment of a mirror module including a flat mirror and a curved mirror scanning the same 3D object and the acquired and/or processed 3D data sets; Fig. 8 is a schematic view of a conventional 3D scanner system for inspecting 3D objects for quality control purposes; and

Fig. 9 is a schematic view of a 3D scanner system in accordance with an embodiment of the present invention for inspecting 3D objects for quality control purposes.

Detailed Description of The Drawings

Figure 1 shows a conventional 3D intraoral scanner 100 for scanning a dentition to generate a 3D digital impression 101 modelling the dentition. 3D intraoral scanners are commercially available from inter alia Carestream Dental, Inc., 3 shape, a.Ttron.3D, Sirona, ZFX, and alike. Particular models include inter alia Carestream Dental CS 3500 Intraoral Scanner, ATron bluescan-I Intraoral Scanner, ZFX Intrascan intraoral scanner, Sirona Omnicam, and others.

The 3D intraoral seamier 100 includes a handheld probe 102 for insertion into a patient's mouth for scanning puiposes. The handheld probe 102 is connected to a 3D surface processing module 103 and a display monitor 104 for displaying the 3D digital impression 101 in real time during scanning. The 3D surface processing module 103 and the display monitor 104 can be implemented as a conventional computer system. The 3D intraoral scanner 100 includes an operator interface 106 for operating same. The operator interface 106 can include manual operated controls on the handheld scanner 102 and display menus for enabling user operated functions.

The handheld probe 102 may include the following modules and components. An illumination module 107 with individual LEDs 108 for illuminating the dentition with visible light illumination. The visible light illumination is typically 420 run illumination. Possibly, the illumination module 107 may project patterned or structured light or may include means such as a laser for projecting a laser dot or line or other shapes onto an object being scanned. Probe 102 may in addition include an acquisition module 109 having a Field of Acquisition (FOA) and capable (possibly by cooperation with processing module 103) of acquiring and processing 3D data sets of the dentition, possibly by processing also information projected by illumination module 107.

A single flat mirror 111 of probe 102 may be deployed in the FOA for reflecting a single reflection of the dentition to the acquisition module 109 for acquisition of a single 3D data set (and/or for acquisition of sensed data information from which such single 3D data set may be processed). Such acquisition and/or processing may be at an instant in time at a given position of the handheld probe 102 relative to the dentition. The acquisition module 109 includes an optical system 112 for processing the light rays reflected from the mirror 1 11 to an image sensor module 1 13 for acquiring 3D data sets.

Figure 2 schematically shows the 3D intraoral scanner 100 scanning a general stepped turret shaped 3D object 200 having a stepped left side surface 201, a stepped right side surface 202, a stepped front side surface 203, a stepped rear side surface 204, and a top surface 206. Figure 2 shows sensor module 113 acquiring and/or processing (possibly by cooperation with processing module 103 ) a 3D data set of the top surface 206.

Figure 3 shows a 3D intraoral scanner 300 according to an embodiment of the invention having a similar construction and operation as the 3D intraoral scanner 100 and therefore similar parts are likewise numbered. The latter 300 differs from the former 100 in several respects as follows.

First, the latter 300 includes an embodiment of a mirror module 301 instead of the single flat mirror 111 in the Field of Acquisition FOA. The mirror module 301 includes at least two mirrors which are deployed in the acquisition module's Field of Acquisition so as to reflect differently angled reflections of the dentition to the acquisition module 109 such that the acquisition module 109 (possibly by cooperation with processing module 103) acquires and processes a corresponding number of different 3D data sets of the dentition from the same given position of the handheld probe 102 relative to the dentition at each instant in time. Second, sensor module 113 (possibly by cooperation with processing module 103) is designed to capture and process a corresponding number of different 3D data sets as mirrors of the mirror module. The sensor module 113 can be implemented by a discrete electronic component for each 3D data set. Alternatively, the sensor module i 13 can be implemented as a single electronic component large enough to capture scanned information pertaining to all the corresponding number of different 3D data sets as mirrors of the mirror module 301.

And third, the 3D surface processing module 103 may be programmed to also stitch the 3D data sets to generate the 3D digital impression 101 of the dentition taking into account that simultaneously captured 3D data sets can be geometrically stitched as opposed to statistically stitched in view of the known geometrical relationship of the mirrors of the mirror module.

The illumination module 107 in an embodiment can optionally include an infrared LED for infrared illumination of the dentition for scanning below a blood saliva mixture which is unable to be scanned under ambient visible light or visible light illumination. Possibly, illumination module 107 may include means capable of projecting patterned or structured light and/or laser beam(s) possible in the form of dots and/or lines (or the like).

Figure 4 shows a mirror module 301 A including a pair of flat mirrors

302 and 303 for scanning the 3D object 200. The mirror pair 302 and 303 is preferably designed such that the mirror 303 is a mirror of the mirror 302 with respect to an imaginary vertical plane therebetween. The mirror module 301 A is designed such that its mirror pair 302 and 303 simultaneously reflects a common part of the 3D object 200 such that their reflection pair includes an overlap region. The overlap region is evidenced by the two 3D data sets 304 and 306 which may include an overlap region such as the hatched area 307

Figure 5 shows a mirror module 30 IB including a pair of flat mirrors 308 and 309 for scanning the 3D object 200. The mirror module 30 IB differs from the mirror module 301 A insofar that the mirror pair 308 and 309 reflect a reflection pair of spaced apart reflections with a smaller overlap region as evidenced by the two different, here illustrated, 3D data sets 31 1 and 312 of the acquired 3D data sets.

Figure 6 shows a mirror module 301C including a pair of flat mirrors

313 and 314 for scanning the 3D object 200. The mirror module 301C is similar to the mirror module 30 IB insofar as the mirror 313 is positioned in the same orientation as the mirror 303 but differs therefrom insofar as the mirror

314 is positioned at a different orientation than the mirror 302. Accordingly, the 3D data set 316 resulting from the mirror 3 13 is the same as the 3D data set 304 but the 3D data set 317 resulting from the mirror 314 is different from the 3D dataset 306.

Figure 7 shows a mirror module 30 ID including a flat mirror 318 and a curved mirror 319 for scanning the 3D object 200. The mirror module 30 ID is similar to the mirror module 301B insofar that the mirror pair 3 18 and 319 reflect a reflection pair of spaced apart reflections with a small overlap region. The mirror module 30 ID is also the same as the mirror module 30 IB insofar as the mirror 318 is positioned in the same orientation as the mirror 308 but differs therefrom insofar as the mirror 319 is curved as opposed to being flat. Accordingly, the 3D dataset 322 resulting from the mirror 318 is the same as the 3D data set 312 but the 3D data set 321 resulting from the mirror 319 is different from the 3D dataset 311.

Figure 8 shows a conventional 3D scanner system 400 including four acquisition modules 401A, 40ΓΒ, 401C and 401D for inspecting 3D objects 200 transported along a conveyor belt 402. The acquisition modules 401 A - 40 ID are deployed orthogonal to one another for correspondingly scamiing the left side surface 201, the right side surface 202, the front side surface 203 and the rear side surface 204. The acquisition modules 401 A - 40 ID also scan portions of the top surface 206 adjacent their respective side surfaces. The 3D scanner system 400 includes a 3D surface processing module 403 for processing 3D data sets from information acquired by each of the acquisition modules 401 A - 40 ID to generate a series of 3D surface files 404 each modelling a 3D object 200. The 3D scanner system 400 also includes a quality control module 406 for determining whether a 3D object satisfies a list of predetermined requirements and issuing an alert on detection of a 3D object which does not satisfy same.

Figure 9 shows a 3D scanner system 500 according to an embodiment of the invention for inspecting the 3D objects 200. The 3D scanner system 500 is similar in construction and operation as the 3D scanner system 400. The latter 500 differs from the former 400 insofar as the latter 500 includes a pair of acquisition modules 501 A and 50 IB deployed orthogonal to one another and such that they scan different 3D objects 200 at the same time.

The acquisition modules 501 A and 50 IB are correspondingly provided with mirror modules 502A and 502B possibly similar to the mirror modules 301 A such that each acquisition module 501 captures two different 3D data sets (and/or sensed information relating thereto) as opposed to a single 3D data set. The acquisition module 501A acquires (possibly by cooperation with a processing module) 3D data sets including front side surface 203, the rear side surface 204 and part of the top surface 206. The acquisition module 50 IB acquires (possibly by cooperation with a processing module) 3D data sets of the left side surface 201, right side surface 202 and the remainder of the top surface 206. Depending on scan technology used, an acquisition module may provide such 3D data sets including other type raw data from which same may be formed and/or processed, such as sensed charge information/data pertaining to reflected e.g. laser energy from locations on a scanned object.

The 3D scanner system 500 also includes a 3D surface processing module 503 for processing the 3D data sets acquired for each 3D object 200 for generating a 3D surface file 504 modelling same and a quality control module 505 for determining whether a 3D object satisfies a list of predetermined requirements and issuing an alert on detection of a 3D object which does not satisfy same.

While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications, and other applications of the invention can be made within the scope of the appended claims.

Claims

CLAIMS:

1. A 3D scanner comprising an acquisition module and a mirror module, the mirror module comprising multiple mirrors angled differently towards a scanned object for simultaneously reflecting each light from at least partially different regions of the object towards the acquisition module, wherein light received via each mirror at the acquisition module is processed to derive a 3D data set of the respective region from which the light is received.

2. The 3D scanner according to claim 1, wherein the simultaneous reflection of light is at a similar instant in time.

3. The 3D scanner according to claim 1 or 2, wherein the simultaneous reflection of light is at a given position of the scanner relative to the object.

4. The 3D scanner according to any one of claims 1 to 3, and comprising an illumination module for projecting illumination towards the object.

5. The 3D scanner according to claim 4, wherein the illumination projected towards the object comprises patterned and/or structured light.

6. The 3D scanner according to claim 4, wherein the illumination projected towards the object originates from a laser, possibly in the form of dots and/or lines.

7. The 3D scanner according to any one of claims 4 to 6, wherein at least part of the light reflected by each mirror towards the acquisition module comprises light of the illumination.

8. The 3D scanner according to any one of claims 1 to 7, wherein the acquisition module comprises a digital image sensor, possibly a CCD or a CMOS.

9. The 3D scanner according to any one of claims 1 to 7, wherein the acquisition module comprises a sensor for measuring a distance to at least part of the scanned object to thereby create a 3D data set, possibly the sensor comprising a charge-coupled device or position sensitive device.

10. The 3D scanner according to any one of claims 1 to 9, and comprising a processing module for stitching together 3D data sets origination from light reflected by different mirrors.

11. The 3D scanner according to claim 10, wherein the stitching comprises geometrically stitching together 3D data sets based on the known geometrical arrangement of the multiple mirrors of a mirror module.

12. A method for scanning an object comprising:

providing a 3D scanner comprising an acquisition module and a mirror module, wherein the mirror module comprising multiple mirrors angled differently one in relation to the other,

projecting illumination towards the object, wherein

light from the illumination reflected off the object and directed by a given mirror towards the acquisition module is processed to derive a 3D data set from the light received via the given mirror.

13. The method of claim 12, wherein the scanner comprising an illumination module and the projecting of illumination is from the illumination module.

14. The method of claims 12 or 13, wherein all the multiple mirrors reflect light simultaneously towards the acquisition module to derive multiple 3D data sets, preferably representative of geometries existing on the object at a similar instant in time.

15. The method of claim 14, and comprising a processing module for geometrically stitching together the multiple 3D data sets.

16. A 3D scanner for modelling a scanned 3D surface of a 3D object, the 3D scanner comprising:

an acquisition module having a field of acquisition and capable of acquiring scanned information for deriving a single 3D data set of at least a portion of the 3D object at an instant in time at a given position of said acquisition module relative to the 3D object; and

a mirror module deployed in said field of acquisition and including multiple mirrors angled differently towards the 3D object for simultaneously reflecting corresponding multiple reflections of different regions of the 3D object at said instant in time at said given position towards said acquisition module, thereby resulting in the scanned information acquired by said acquisition module being comprised of multiple sub- sets of information relating each to a different region on the scanned 3D surface of the 3D object, wherein said single 3D data set comprising multiple 3D sub-sets each being derived from a respective one of the sub-sets of information.

17. The 3D scanner accordmg to claim 16 and comprising a 3D surface processing module for processing said scanned information to generate said 3D data sets.

18. The 3D scanner according to claim 16 or 17, wherein a reflection pair of said multiple reflections includes an overlap region.

19. The 3D scanner accordmg to claim 16 or 17, wherein a reflection pair of said multiple reflections are spaced apart reflections with no overlap region.

20. The 3D scanner accordmg to any one of claims 16 to 19 wherein said mirror module includes at least one flat mirror.

2 1. The 3D scanner according to any one of claims 16 to 19 wherein said mirror module includes at least one curved mirror.

22. The 3D scanner accordmg to any one of claims 16 to 21 and further comprising an illumination module for illuminating the 3D object with non- visible light illumination.

23. The 3D scanner accordmg to any one of claims 16 to 21 and further comprising an illumination module for illuminating the 3D object with patterned or structured light.

24. The 3D scanner according to any one of claims 16 to 23 wherein said mirror module is interchangeable thereby enabling the use of different mirror modules with said acquisition module.

25. The 3D scanner according to any one of claims 16 to 24 wherein said acquisition module and its associated mirror module constitute an integral module movable with respect to the 3D object.

26. The 3D scanner according to anv one of claims 16 to 24 wherein said acquisition module and its associated mirror module constitute an integral module stationary with respect to the 3D object.

27. A 3D scanner system including at least two acquisition modules and associated mirror modules according to any one of claims 16 to 26.