Intraoral scanner with force sensitive user interface

Abstract

The disclosure relates to a 3D scanner system for scanning an object of an oral cavity of a patient during a scanning session. The scanner system comprises an intraoral scanner. The intraoral scanner comprises one or more cameras configured for capturing images of the object for the provision of image data. The intraoral scanner comprises an outer shell made in one piece, the outer shell having an internal surface and an external surface. The intraoral scanner comprises a user interface configured for controlling one or more processes of the scanning session, wherein the user interface comprises one or more force sensor(s) arranged at the internal surface to provide a touch sensitive zone of the external surface of the outer shell, the one or more force sensor(s) being configured for detecting two or more levels of force applied by a user touching external surface of the touch sensitive zone. The scanner system comprises one or more processors configured to generate a 3D representation of the object based on the image data.

Description

[0001] Intraoral scanner with force sensitive user interface

[0002] Technical field

[0003] The present disclosure relates to a 3D scanner system comprising an intraoral scanner with a force sensitive user interface.

[0004] Background

[0005] Digital dental scanning systems comprising an intraoral scanner are playing an important role in transforming both restorative and orthodontic dentistry. Real-time imaging using the scanning systems allows for generating three-dimensional digital models of single or multiple teeth, whole arches which may include restorations or implants, opposition arches, occlusion, and surrounding soft tissue or even dentures for edentulous patients.

[0006] The intraoral scanner is used during scanning sessions where it is operated by a user and partly inserted into the mouth of a patient to capture image data of at least a part of the patient’s oral cavity. To control the scanning process, intraoral scanners usually comprise a user interface with one or more buttons which enables the user to initiate a scan or move between scanning steps without interacting with other devices, e.g. a keyboard or mouse, which could cause contamination of the user’s hands, which in turn could lead to an infection for the patient.

[0007] A drawback of such a user interface is that button interface provides seams between the buttons and the housing, in which dirt or pathogens may accumulate unless cleaned properly. Even when the buttons themselves are protected with a flexible cover, e.g. made of silicone or rubber, so that the buttons remain unexposed, the seam between the cover and the housing remains exposed and capable of collecting dirt. Button interfaces may thus pose a hygienic risk if not cleaned regularly.

[0008] Another drawback is that buttons provide rather limited control of the scanning session. Push buttons are usually binary user interfaces, which by themself are limited to single commands, or few commands if multiple consecutive pushes are also associated with commands. Providing multiple buttons may mitigate this, but providing an intraoral scanner with too many buttons often lead to miss presses by the user or even confusion as the user may forget or mistake the commands associated with the respective buttons.

[0009] It thus remains a need to provide an intraoral scanner with an improved user interface. Summary

[0010] An aspect of the present disclosure accomplishes this by a 3D scanner system for scanning an object of an oral cavity of a patient during a scanning session. The scanner system comprises an intraoral scanner. The intraoral scanner comprises one or more cameras configured for capturing images of the object for the provision of image data. The intraoral scanner comprises an outer shell made in one piece, the outer shell having an internal surface and an external surface. The intraoral scanner comprises a user interface configured for controlling one or more processes of the scanning session, wherein the user interface comprises one or more force sensor(s) arranged at the internal surface to provide a touch sensitive zone of the external surface of the outer shell, the one or more force sensor(s) being configured for detecting two or more levels of force applied by a user touching external surface of the touch sensitive zone. The scanner system comprises one or more processors configured to generate a 3D representation of the object based on the image data.

[0011] Each force sensor configured for detecting two or more levels of force may mimic a multi-stage push button as each level of force may be associated with different commands of the user interface. A more versatile user interface is thus provided compared to intraoral scanners of the prior art which utilized single stage push buttons. It is noted that in this context the absence of a touch is not considered to be a detection. Traditional touch sensors which distinguish between touch or no touch, i.e. a binary detection, can thus not be considered to be able to detect two levels of force but just one.

[0012] Because the touch sensitive zone forms part of the outer shell, the outer shell may have a continuous outer surface without the grooves and through holes required to provide traditional push button interfaces. The disclosed user interface therefore provides fewer places for dirt and pathogens to accumulate and thus makes it easier for the user to clean the scanner between patients. A more hygienic user interface is thus provided.

[0013] Brief description of the drawings

[0014] The above and other features and advantages of the present invention will become readily apparent to those skilled in the art by the following detailed description of exemplary embodiments thereof with reference to the attached drawings, in which:

[0015] Fig.1 shows a 3D scanner system for scanning an object of an oral cavity,

[0016] Fig. 2 shows an intraoral scanner of the prior art, Fig. 3 shows a cross-sectional view of an intraoral scanner of the invention,

[0017] Fig. 4 shows a perspective view of an intraoral scanner of the invention,

[0018] Fig. 5 shows a cross-sectional view of an intraoral scanner of the invention,

[0019] Fig. 6 shows a cross-sectional view of an intraoral scanner of the invention,

[0020] Fig. 7 shows a perspective view of an intraoral scanner of the invention,

[0021] Fig. 8 shows a cross-sectional view of an intraoral scanner of the invention,

[0022] Fig. 9 shows a perspective view of an intraoral scanner of the invention,

[0023] Fig. 10a shows a cross-sectional view of an intraoral scanner of the invention,

[0024] Fig. 10b shows a cross-sectional view of an intraoral scanner of the invention,

[0025] Fig. 11 shows a perspective view of an intraoral scanner of the invention,

[0026] Fig. 12 shows a cross-sectional, schematic view of a touch pad area,

[0027] Fig. 13 shows a cross-sectional, schematic view of a touch pad area,

[0028] Fig. 14 shows a cross-sectional, schematic view of a force sensitive area,

[0029] Fig. 15 shows a cross-sectional, schematic view of a force sensitive area,

[0030] Fig. 16 shows a cross-sectional, schematic view of a force sensitive area,

[0031] Fig. 17 shows various shapes of a touch pad area, and

[0032] Fig. 18 shows various shapes of a touch pad area.

[0033] Detailed description

[0034] The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. Several aspects of the devices, systems, mediums, programs and methods are described by various blocks, functional units, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as “elements”). Depending upon particular application, design constraints or other reasons, these elements may be implemented using electronic hardware, computer program, or any combination thereof.

[0035] Disclosed is a 3D scanner system for scanning an object of an oral cavity of a patient during a scanning session, the scanner system comprising:

[0036] - an intraoral scanner comprising:

[0037] ■ one or more cameras configured for capturing images of the object for the provision of image data,

[0038] ■ an outer shell made in one piece, the outer shell having an internal surface and an external surface, and

[0039] ■ a user interface configured for controlling one or more processes of the scanning session, wherein the user interface comprises one or more force sensor(s) and / or a capacitive sensor array arranged at the internal surface to provide a touch sensitive zone of the outer shell, the one or more force sensor(s) and / or the capacitive sensor array being configured for detecting a user touching the external surface of the touch sensitive zone,

[0040] - one or more processors configured to generate a 3D representation of the object based on the image data.

[0041] The capacitive sensor array is configured for detecting whether a user is touching the external surface or not and at which location, whereby the capacitive sensor array provides a touch pad area of the touch sensitive zone. The force sensor(s) is / are configured for detecting an amount of force applied in a direction which is normal to the external surface, whereby the one or more force sensor(s) each provide a force sensitive area of the touch sensitive zone.

[0042] By providing the user interface comprising force sensor(s) and / or a capacitive sensor array capable of detecting a user’s touch of the external surface arranged inside the housing, interaction devices such as push buttons may be omitted in favor of a continuous outer surface which is less prone to accumulating dirt and pathogens and is also easier to clean. A more hygienic scanner is therefore provided.

[0043] An object of an oral cavity is to be understood as a three-dimensional object inside the oral cavity of a person. Examples of objects of the oral cavity include one or more of: tooth / teeth, implant(s), dental restoration(s), crowns, braces, dental prostheses, edentulous ridge(s), gingiva, or combinations thereof. The objects of the oral cavity are typically situated in a dental arch in the patient’s mouth. In some cases, the patient misses one or more teeth. In such cases, the scanner system is preferably configured to determine the scan coverage regardless. In some embodiments, a visualization of the scan coverage of the dental arch is generated and displayed, wherein the teeth and / or missing teeth are visualized e.g. using different colors.

[0044] The intraoral scanner may employ a scanning principle such as triangulation-based scanning, confocal scanning, focus scanning, ultrasound scanning, x-ray scanning, stereo vision, structure from motion, optical coherent tomography OCT, or another scanning principle. The intraoral scanner may be a handheld device.

[0045] In some embodiments, the intraoral scanner is operated by projecting a pattern and translating a focus plane along an optical axis of the intraoral scanner and capturing a plurality of 2D images at different focus plane positions. The series of captured 2D images corresponding to each focus plane then forms a stack of 2D images. The focus plane position is preferably shifted along the optical axis of the intraoral scanner, such that 2D images captured at a number of focus plane positions along the optical axis form said stack of 2D images for a given view of the object, i.e. for a given arrangement of the scanner relative to the object. After moving the intraoral scanner relative to the object or imaging the object at a different view, a new stack of 2D images for that view may be captured. The acquired 2D images may be processed to generate 3D scan data, also referred to herein as a sub-scan.

[0046] The focus plane position may be varied by means of at least one focus element, e.g., a moving focus lens. The intraoral scanner is generally moved and angled during a scanning session, such that at least some sets of sub-scans overlap at least partially, in order to enable stitching in a postprocessing routine. The result of stitching is a digital 3D representation of the scanned object. Stitching, also known as registration, works by identifying overlapping regions of 3D surface in various sub-scans and transforming sub-scans to a common coordinate system such that the overlapping regions match, finally yielding the digital 3D model. An Iterative Closest Point (ICP) algorithm may be used for this purpose.

[0047] In other embodiments, the intraoral scanner is a triangulation-based scanner, which utilizes one or more cameras located at an angle relative to a projector unit to determine depth based on triangulation. In such embodiments, the intraoral scanner comprises one or more scan units, wherein each scan unit comprises a projector unit and one or more cameras. A scan unit may be understood herein as a unit comprising at least one projector unit and one or more cameras. In some embodiments, each scan unit comprises at least two cameras having at least partly overlapping fields of view along different camera optical axes. Preferably, each scan unit comprises at least four cameras having at least partly overlapping fields of view along different camera optical axes. A scan unit may further comprise one or more lenses such as collimation lenses or projection lenses. A camera may be understood herein as a device for capturing an image of an object. Each camera comprises an image sensor for generating an image based on incoming light e.g. received from the illuminated 3D object. Each camera may further comprise one or more lenses for focusing light.

[0048] As an example, the intraoral scanner may comprise one scan unit comprising one projector unit and at least two cameras. As another example, the intraoral scanner may comprise one scan unit comprising one projector unit and four cameras. In yet another example, the intraoral scanner may comprise at least two scan units, wherein each scan unit comprises a projector unit and two or more cameras. In yet another example, the intraoral scanner may comprise at least two scan units, wherein each scan unit comprises a projector unit and four cameras. In accordance with some embodiments, the projector optical axis and the camera optical axis of at least one camera define a camera-projector angle of approximately 5 to 15 degrees, preferably 5 to 10 degrees, even more preferably 8 to 10 degrees.

[0049] The scan units may further comprise a reflecting element. A reflecting element may be understood herein as an element configured to change the direction of light passing through or hitting the surface of said reflecting element. In particular, the reflecting element is preferably configured to change the direction of a center beam of the projected light from a projector unit from a direction substantially parallel to the longitudinal axis of the scanning device to a direction substantially orthogonal to said longitudinal axis. The reflecting element may be selected from the group of: mirrors, prisms, and / or combinations thereof. In preferred embodiments, the reflecting element is configured to reflect light from the projector unit(s) of at least one scan unit and / or reflect light from the surface of object being scanned and onto the image sensor(s) of at least one scan unit.

[0050] The intraoral scanner may utilize a time varying pattern featuring a sequence of different pattern configurations and / or colors, which is projected onto the dental object. In other embodiments, the intraoral scanner is configured to project a static pattern onto the surface of the dental object.

[0051] The intraoral scanner may comprise one or more projector units configured to generate an illumination pattern to be projected on a three-dimensional dental object during a scanning session. The projector unit(s) preferably comprises a light source, a mask having a spatial pattern, and one or more lenses such as collimation lenses or projection lenses.

[0052] The light source may be configured to generate light of a single wavelength or a combination of wavelengths (mono- or polychromatic). The combination of wavelengths may be produced by using a light source configured to produce light (such as white light) comprising different wavelengths. Alternatively, the projector unit(s) may comprise multiple light sources such as LEDs individually producing light of different wavelengths (such as red, green, and blue) that may be combined to form light comprising the different wavelengths. Thus, the light produced by the light source may be defined by a wavelength defining a specific color, or a range of different wavelengths defining a combination of colors such as white light.

[0053] In some embodiments, the intraoral scanner comprises a light source configured for exciting fluorescent material to obtain fluorescence data from the dental object such as from teeth. Such a light source may be configured to produce a narrow range of wavelengths. The intraoral scanner may additionally or alternatively comprise an infrared light source configured to generate wavelengths in the infrared range, such as between 700 nm and 1.5 pm. In some embodiments, the intraoral scanner comprises a light source selected from the group of: Infrared (IR) light source, nearinfrared (NIR) light source, blue light source, violet light source, and / or combinations thereof.

[0054] The projector unit(s) may be Digital Light Processing (DLP) projectors using a micro mirror array for generating a time varying pattern, or a diffractive optical element (DOF), or front-lit reflective mask projectors, or micro-LED projectors, or Liquid crystal on silicon (LCoS) projectors or back-lit mask projectors, wherein a light source is placed behind a mask having a spatial pattern, whereby the light projected on the surface of the dental object is patterned. The pattern may be dynamic, i.e. such that the pattern changes over time, or the pattern may be static in time, i.e. such that the pattern remains the same over time. The projector unit(s) may comprise a collimation lens for collimating the light from the light source, said collimation lens being placed between the light source and the mask. The projector unit(s) may further comprise one or more focus lenses configured for focusing the light at a predefined focus distance.

[0055] The intraoral scanner preferably further comprises optical components for directing the light from the light source to the surface of the dental object. The specific arrangement of the optical components depends on whether the intraoral scanner is a focus scanning apparatus, a triangulation-based scanner, or any other type of scanning device. A focus scanning apparatus is further described in EP 2 442 720 B1 by the same applicant.

[0056] The light reflected from the dental object in response to the illumination of the dental object is directed, using optical components of the intraoral scanner, towards the image sensor(s). The image sensor(s) are configured to acquire one or more images based on the incoming light received from the illuminated dental object. The image sensor may be a high-speed image sensor such as an image sensor configured for acquiring images with exposures of less than 1 / 1000 second or frame rates in excess of 250 frames pr. second (fps). As an example, the image sensor may be a rolling shutter (CCD) or global shutter sensor (CMOS). The image sensor(s) may be a monochrome sensor including a color filter array such as a Bayer filter and / or additional filters that may be configured to substantially remove one or more color components from the reflected light and retain only the other non-removed components prior to conversion of the reflected light into an electrical signal. For example, such additional filters may be used to remove a certain part of a white light spectrum, such as a blue component, and retain only red and green components from a signal generated in response to exciting fluorescent material of the teeth. The image sensor may also be a color image sensor for generating color images.

[0057] The intraoral scanner is configured for generating image data based on the two-dimensional (2D) images acquired by the intraoral scanner. The 3D scanner system further comprises one or more processors configured to generate scan data by processing the image data. The processor(s) may be part of the intraoral scanner, or they may be external to the scanner such as part of a computer system. As an example, the processor(s) may be selected from the group of: central processing units (CPU), accelerators (offload engines), general-purpose microprocessors, graphics processing units (GPU), neural processing units (NPU), application-specific integrated circuits (ASIC), field- programmable gate arrays (FPGA), dedicated logic circuitry, dedicated artificial intelligence processor units, or combinations thereof. In some embodiments, the intraoral scanner comprises a Field-programmable gate array (FPGA) and an ARM processor.

[0058] The scan data comprises information relating to the three-dimensional dental object. The scan data may comprise any of: 2D images, 3D point clouds, depth data, texture data, intensity data, color data, and / or combinations thereof. As an example, the scan data may comprise one or more point clouds, wherein each point cloud comprises a set of 3D points describing the three-dimensional dental object. As another example, the scan data may comprise images, wherein each image comprises image data. In some cases, the image data contains image coordinates and a timestamp (x, y, t), wherein depth information can be inferred from the timestamp. The image sensor(s) of the intraoral scanner may acquire a plurality of 2D images of the dental object in response to illuminating said object using the one or more projector units. The plurality of 2D images may also be referred to herein as a stack of 2D images.

[0059] The 2D images may subsequently be provided as input to the one or more processors, which are configured to process the 2D images to generate scan data, such as depth map(s). The processing of the 2D images may comprise the step of determining which part of each of the 2D images are in focus in order to deduce / generate depth information from the images. The depth information may be used to generate 3D point clouds comprising a set of 3D points in space, e.g. , described by cartesian coordinates (x, y, z). Each 2D / 3D point may furthermore comprise a timestamp that indicates when the 2D / 3D point was recorded, i.e., from which image in the stack of 2D images the point originates. The timestamp is correlated with the z-coordinate of the 3D points, i.e., the z-coordinate may be inferred from the timestamp. Accordingly, one output of the processor may be scan data, and the scan data may comprise image data and / or depth data, e.g. described by image coordinates and a timestamp (x, y, t) or alternatively described as (x, y, z). The intraoral scanner may be configured to transmit other types of data in addition to the scan data. Examples of types of data include 3D information, texture information, infra-red (IR) images, fluorescence images, reflectance color images, x-ray images, and / or combinations thereof.

[0060] We note that these image coordinates are not linked to the coordinates used later in the description of the figures.

[0061] The intraoral scanner comprises a user interface configured for initiating an action or operation upon activation. The user interface may be selected from the group of: mechanical buttons, reconfigurable buttons, touch sensitive zones or buttons, touchscreens, and / or combinations thereof. The user interface(s) may be recessed in a surface of the intraoral scanner. The user interface(s) may be configured to initiate one or more actions, such as: initiating a scan, stopping a scan, navigating in a graphical user interface, selecting a menu item, acquiring a single image, proceeding to a next or previous step in a scanning workflow, undoing a previous action, initiating a fluorescence or infrared scan, interacting with the 3D representation (e.g. zoom and / or rotate), uploading the 3D representation to the cloud, etc. In some embodiments, the user interface comprises one or more mechanical buttons and / or one or more reconfigurable buttons.

[0062] The user interface may comprise a touch sensitive zone configured for detecting a touch input of the user. The user interface may comprise a combination of touch technology and traditional buttons, i.e. mechanical buttons. In some embodiments, the touch sensitive zone is based on force touch technology rather than capacitive sensing. This may be achieved by placing one or more strain gauges under the touch sensitive zone, wherein each of said strain gauges are configured to detect strain / deformation in the material(s) above the strain gauge. As an example, four strain gauges may be positioned, e.g. in a cross. Then, the four strain gauges are configured to detect user input such as touch presses and / or swiping actions. Thus, the strain gauges may be configured to emulate capacitive sensing, however with some advantages over capacitive sensing. An advantage of utilizing force touch technology based on strain gauges is that the touch sensitive zone may be operated in wet conditions and when using gloves. This can be challenging when operating touch sensitive zones based on capacitive sensing. The scanner may further be configured to provide haptic feedback correlated with use of the touch sensitive zone. As an example, the scanner may provide haptic feedback, e.g. vibration, when the user presses the touch sensitive zone and / or when the user performs a swiping action using the touch sensitive zone.

[0063] In some embodiments, the intraoral scanner further comprises an illumination ring, such as a lightemitting diode (LED) ring, which is located along the circumference of the touch sensitive zones. The illumination ring preferably constitutes a full circle but in some cases it may only form part of a circle. Other shapes can also be envisioned. The illumination ring may be configured to display a simplified visualization of the dental arch being scanned. The visualization may simply be the illumination of the ring itself, e.g. wherein a first part of the illumination ring is configured for displaying information related to a lower arch of the patient, and wherein a second part of the illumination ring is configured for displaying information related to an upper arch of the patient. The first and second parts may each constitute a half circle such that the first and second parts in combination constitutes a full circle. A third and / or fourth part of the illumination ring may be configured for displaying information related to a bite scan procedure within the scanning session. The third and fourth parts may be opposite to each other and the third or fourth part is preferably used to display information related to a left or right bite scan procedure. Furthermore, the third and / or fourth parts may overlap the first and / or second part of the illumination ring.

[0064] The illumination, brightness, and / or color of the illumination ring may be correlated with the generated scan data of a given dental arch, such that the illumination ring is configured to inform the user of the local / global scan coverage. Thus, the illumination ring may be configured to visualize a progress of the scanning session and / or whether sufficient scan data has been obtained. The illumination ring may be configured to visualize the part(s) of the upper / lower arch which has been scanned, i.e. for which 3D scan data has been acquired. The illumination ring may be configured to utilize one or more colors to visualize the local / global scan coverage. As an example, green may be used to denote areas for which sufficient 3D scan data has been generated, and yellow may be used to denote areas for which insufficient 3D scan data exists, i.e. areas which have a low local scan coverage. Other colors may also be utilized. Alternatively, the brightness of the illumination ring may be correlated with the local and / or global scan coverage. Once a given part of the illumination ring, e.g. the first part, is fully green (or another suitable color), the scanner may be configured to provide a sound for signaling that the user can move on to scanning the other dental arch (e.g. upper or lower jaw). This may similarly be implemented for the third and / or fourth part, i.e. when the bite scan is completed the scanner may provide a sound. This is exemplified in figure 6. Finally, the illumination ring may be configured to be fully lit with a predefined color, such as green, once the scanning session is completed.

[0065] In some embodiments, the intraoral scanner comprises a feedback light source, such as a lightemitting diode (LED), located on the intraoral scanner. The feedback light source is preferably located such that it is visible from outside the scanner. The feedback light source is preferably configured to change illumination, brightness and / or color, wherein the change is correlated with the local and / or global scan coverage measure. In preferred embodiments, the feedback light source is configured to light up and / or change color when the local scan coverage measure reaches a predefined threshold value, such that the intraoral scanner signals when enough 3D scan data has been obtained for a given dental object. It may similarly be configured to be associated with the global scan coverage. As an example, the feedback light source may turn green once enough 3D scan data has been generated for a given dental object, such as a tooth. Thereby, the user receives a feedback, which is visible inside the patient’s mouth while scanning, whereby the user knows to proceed to scanning the next dental object in the mouth. The feedback light source may further be used for displaying a status of the scanner. In some embodiments, the feedback light source is configured to change color based on detecting the presence of bacteria, e.g. in response to a fluorescence emission captured by the scanner.

[0066] Each of the one or more force sensor(s) may be configured for detecting two or more levels of force applied by a user touching external surface of the touch sensitive zone. This has the advantage that the force sensors may detect not only whether a user is touching the touch sensitive zone, but also distinguish how hard the user is pressing. As a result, the user interface becomes capable of taking more types of commands because each force level can be associated with an individual command.

[0067] At least one force sensor of the one or more force sensor(s) may be arranged over or under the capacitive sensor array. By arranging force sensors and the capacitive sensor array stacked on each other, a touch sensitive zone which is both touch and force sensing is provided, i.e. a force-touch sensitive zone or three dimensional touch interface. Such an interface provides improved interaction possibilities and thus a more versatile user interface.

[0068] The touch pad area provided by the capacitive sensor array or an array of force sensors is configured for detecting a user’s moving touch of the external surface, i.e. a user touching the touch pad area and moving their finger. While the capacitive sensor array is often the better choice over force sensors for providing a touch pad area, the force sensors may also be provided closely in an array, whereby they may also track a moving touch, e.g. a user swiping their finger over the touch sensitive area.

[0069] The 3D scanner system may comprise a feedback device configured for outputting a feedback signal based on a detection of the touch sensitive zone being touched by the at least one of the one or more force sensor(s) and / or by the capacitive sensor array. A disadvantage of using the disclosed touch sensitive zone as an interface is the lack of feedback, e.g. compared to the tactile feedback when pushing a mechanical push button. This may be remedied by providing a feedback device which provides a feedback signal when an input is detected, whereby the user is assured that their input was detected.

[0070] The strength of the feedback signal may be based on the level of force detected by at least one of the one or more force sensor(s). That is the feedback signal may be output in a stronger form, e.g. volume, intensity, frequency, etc. Unlike push buttons, the force sensitive area(s) won’t be able to provide the user with a tactile, clicking sensation when it is pushed. It may therefore be advantageous to provide a feedback signal which is based on the level of force applied by the user, so that the user is informed about what input they are providing and in turn also which action they are initiating. The feedback signal may comprise one or more of the following: a haptic signal, an audio signal, a visual signal, or a combination hereof. Haptic signals may be output by a vibration device of the intraoral scanner so that the user can feel when they are providing an input, and they have the advantage of providing a tactile feedback similar to that of a pushbutton, which may help the user operate the intraoral scanner of the invention more easily. Audio signals may be output by a loudspeaker of the 3D scanner system and optionally of the intraoral scanner. Audio signals may have the advantage that the scanner remains steady, unlike haptic feedback, during use and allows the user to maintain visual focus on the scanning process. A visual signal, such as a light signal may be generated by a light source of the 3D scanner system, optionally comprised by the intraoral scanner, e.g. a display or a LED light emitter. Visual signals may have the advantage of

[0071] The feedback device may be comprised by the intraoral scanner. The feedback device may comprise a vibration device, a light emitter, and / or a loud speaker. The feedback signal may be a tactile signal, and the feedback device may be located at the touch sensitive zone and be configured for generating the tactile signal at a position of the touch sensitive zone where the detection of the touch sensitive zone being touched was detected.

[0072] The exterior surface of the touch sensitive zone may comprise one or more protrusion(s). The exterior surface of the touch sensitive zone may comprise one or more depression(s). It is advantage to make the touch sensitive zone distinguishable from the remainer of the external surface so that the user may easily locate where to place their fingers. Protrusion and / or depressions may be used to allow the user to quickly find the touch sensitive zone as they may identify it from the level difference of the external surface of the touch sensitive zone relative to the external surface surrounding the touch sensitive zone.

[0073] The exterior surface of the touch sensitive zone may comprise one or more color marking(s) at the external surface. The exterior surface of the touch sensitive zone may have a different surface roughness relative to the exterior surface surrounding the touch sensitive zone. Color markings and / or surface roughness may be used as an addition or alternative to distinguishing the touch sensitive zone by level, i.e. using protrusions and / or depressions, to allow the user to easily locate the touch sensitive zone and operate the intraoral scanner.

[0074] The one or more protrusion(s), one or more depression(s), and / or one or more color marking(s) is / are arranged at one or more position(s) of the touch sensitive zone where a force sensor of the one or more force sensor(s) and / or the capacitive sensor array is / are arranged at the internal surface. The one or more protrusion(s), one or more depression(s), and / or one or more color marking(s) indicate(s) a position of the touch sensitive zone, at which position a force sensor of the one or more force sensor(s) and / or the capacitive sensor array is / are configured to detect touch. The capacitive sensor array may be arranged on a flexible PCB. Arranging the capacitive sensor array on a flexible PCB both simplifies manufacturing and allows the capacitive sensor array to be arranged against a curved internal surface of the outer shell. The capacitive sensor array may be configured to detect touch based on capacitive coupling through self-capacitance between an electrode and a ground plane and / or on capacitive coupling through mutual capacitance between two or more electrodes. Each of the one or more force sensors may be provided by one or more of a strain gauge sensor, a piezo-electric sensor, a capacitive sensor, an ultrasound sensor, or any combination hereof. Ultrasound based touch sensing may be advantageous in embodiments where the outer shell is made from a metal or metallic alloy as it can function regardless of whether the outer shell is electrically conducting or not. An ultrasound based touch sensing sensor may transmit and receive ultrasound beams through material stacks, e.g. the outer shell, using an array of Piezoelectric Micromachined Ultrasound Transducers (PMUTs).

[0075] The touch sensitive zone may arranged on a top side of the intraoral scanner. In this regard, the top side is defined as the side opposite the optical aperture of the tip of the intraoral scanner. The touch sensitive zone may extend fully or partially the circumference of the intraoral scanner.

[0076] The external surface of the touch sensitive zone may be a curved surface. The touch sensitive zone may comprise a curved surface. The curved surface may be curved along a width direction (y) of the intraoral scanner and substantially straight along a longitudinal direction (x) of the intraoral scanner. The external surface of the touch sensitive zone may comprise a convex surface. The external surface of the touch sensitive zone may comprise a concave surface.

[0077] The touch pad area may extend in a longitudinal direction (x) and in a width direction (y). The extension in the longitudinal direction is at least 1.5 times the extension in the width direction, preferably 2 times the extension in the width direction, more preferably 2.5 times the extension in the width direction.

[0078] The touch sensitive zone may comprise two or more discrete spots, wherein at least one force sensor of the one or more force sensor(s) is / are arranged at each of the spots. The user interface may comprise two or more force sensors. The user interface may comprise two force sensors. At least two force sensors of the two or more force sensors may be arranged in a line extending substantially parallel with the longitudinal axis of the intraoral scanner.

[0079] The user interface may be configured for, when multiple force sensors of the two or more force sensors make simultaneous detections, comparing the force levels of the simultaneous detections, and discarding the simultaneous detections unless at least one of the simultaneous detections differs in force level from the others by more than a threshold value. For force sensors, an issue which may occur is false positive detections. This is because the force sensors detect the bending of the outer shell, and since such bending extends over an area larger than the touched position, any touch in the vicinity of a force sensor will trigger a detection, even a touch outside the touch sensitive area. But where a touch inside the touch sensitive zone, i.e. an intended touch, cause the force sensor at the touch location to experience a strong detection and other force sensors to experience a weaker signal, an unintentional touch outside the touch sensitive area will only produce several weak signals. Thus, by discarding detection events of multiple simultaneous detections, where one detection is not significantly stronger than the others, false positive detections may be ignored. The user interface may be configured for discarding detections of the one or more force sensor(s), when the detected force is below an activation threshold.

[0080] The user interface may comprise a secondary interaction device. The secondary interaction device may comprise one or more movement sensors configured for detecting movement of the intraoral scanner. The one or more movement sensors comprises one or more of the following: an accelerometer, a gyroscope, a magnetometer, or a combination hereof. The one or more movement sensors is / are configured for detecting one or more of the following: pitch of the intraoral scanner, roll of the intraoral scanner, yaw of the intraoral scanner, or a combination hereof. The one or more movement sensors is / are configured for detecting linear displacement of the intraoral scanner.

[0081] The outer shell may be made of a material comprising one or more of the following, a polycarbonate, acrylonitril-butadien-styren (ABS), or a mixture hereof. The outer shell may be made from a material having a tensile modulus between 1800-2800 MPa when measured with the ISO 527-1 ,-2 Standard at test conditions of 1 mm / min. The outer shell may have a thickness between 0.25 - 2.1 mm at the touch sensitive zone. While a thinner outer shell makes it easier to detect the users touch at the internal surface it has to be balanced with structural stability to ensure the durability of the housing. The inventors found that making the outer shell of a material with the stiffness disclosed above and with this thickness at the touch sensitive zone disclosed above a good compromise between structural stability and touch detection sensitivity is provided.

[0082] Each of the one or more force sensor(s) may be configured for detecting a first level of force between about 0.1 to about 0.3 N applied by a user touching external surface of the touch sensitive zone, and for detecting a second level of force between about 0.3 to about 0.6 N applied by a user touching external surface of the touch sensitive zone. The inventors found that these intervals were found to be the most intuitive amongst users, thereby providing an intraoral scanner which is easier to operate and provide and improved user experience.

[0083] Fig. 1 illustrates a 3D scanner system 10 for scanning an object 310 of an oral cavity of a patient 300 during a scanning session. The scanner system 10 comprises an intraoral scanner 100 which is a handheld device operated by a user, e.g. a dentist or a dental technician. The intraoral scanner 100 comprises a proximal end with a handle part for being held by the user, and a distal end with a tip for being inserted into the mouth of the patient 310 during the scanning session. The intraoral scanner 100 comprises one or more projector units configured for illuminating the object 310 and one or more cameras configured for capturing images of the object 310. At the tip, the intraoral scanner 100 comprises an optical opening through which the one or more projector units may project light onto the object 310 and the one or more cameras may capture light reflected of the object 310. The intraoral scanner 100 may generate image data based on the captured images.

[0084] For the scanning session, the intraoral scanner 100 may be operably connected to a scanning station 200, such as a laptop or desktop computer, which may provide the user with a real-time viewfinder displayed on a screen 210 to help the user maneuver the scanner 100 inside the patient’s 300 mouth during the scanning session. The image data generated based on one or more images captured during the scanning session can be processed by one or more processors into a 3D representation 20 of the object 310. The 3D representation 20 may also be displayed on the screen 210 so that the user may examine and inspect the object 310.

[0085] Fig. 2 illustrates an intraoral scanner 100 of the prior art. Such scanners usually comprise a push button interface 102 which provides the user control of the scanner 100 and of processes of the scanning session. Such button interfaces 102 may require extra attention during cleaning of the scanner 100 as dirt and pathogens may accumulate around the button(s). Furthermore, while button interfaces 102 have proved reliable and to some extend sufficient, they do have limitation in the number of commands that can be associated with them, even when including button press patterns such as prolonged pushes and double-clicks.

[0086] Fig. 3 shows a cross-sectional view of an intraoral scanner 100 of the present disclosure. The intraoral scanner 100 comprises a housing which at least partially encloses an internal volume 118 in which the one or more projector units, the one or more cameras, and other electrical components may be housed. The housing comprises an outer shell 110 made in one piece, wherein the outer shell 110 has an internal surface 114 facing the internal volume 118 and an external surface 112 facing the exterior environment. The outer shell 110 may form the entire housing, i.e. the housing is provided by a single shell. Alternatively, the housing may be provided by a shell assembly comprising the outer shell and one or more additional shell components.

[0087] For wireless intraoral scanners like the one shown here, the intraoral scanner 100 will also comprise a power device such as a battery 190 to provide the intraoral scanner with energy. Most intraoral scanners also comprise a replaceable hygienic tip barrier 180 arranged at the distal end of the intraoral scanner, which can be exchanged between patients so that the part of the intraoral scanner 100 that has been in contact with the oral cavity of the patient is not reused between patients, at least not without proper cleaning such as an autoclave process. The hygienic tip barrier 180 comprises an optical aperture, which is almost always covered by a window, through which the projector unit may illuminate the object 310 and through which the one or more cameras may capture images of the object 310.

[0088] The intraoral scanner 100 comprises a user interface configured for controlling one or more processes of the scanning session. The user interface comprises one or more force sensors 120, e.g. one force sensor 120 in the shown embodiment. The force sensors 120 are arranged at the internal surface 114 and are configured for detecting bending of the outer shell 110 caused by a user touching the external surface 112, so that a force sensitive area 116a of the outer shell 110 is provided. Each of the one or more force sensor(s) 120 is / are configured for detecting two or more levels of force applied in a direction (z) which is normal to the external surface 112 of the force sensitive area 116a. This allows each force sensor 120 to mimic a multi-stage push button as the force sensors 120 not only detect whether the user is touching the force sensitive area 116a, but also detects how hard the user is touching the force sensitive area 116a.

[0089] The user interface further comprises a capacitive sensor array 122 arranged at the internal surface 114. Like the one or more force sensor(s) 120, the capacitive sensor array 122 is configured for detecting a user’s touch of the external surface 112, but unlike the force sensor(s) 120 the capacitive sensor array 122 need not be configured for distinguishing between multiple levels of force applied to the external surface 112. Instead, the capacitive sensor array 122 need only be configured for detecting whether the user is touching the external surface 112 and at which location so that the capacitive sensor array 122 provides a touch pad area 116b configured for detecting continuous touch in a direction parallel to the external surface 122, i.e. the in the x-y plane.

[0090] The intraoral scanner 100 is thus provided with a touch sensitive zone having one or more force sensitive area(s) 116a and / or a touch pad area 116b. When the touch sensitive zone comprises both one or more force sensitive area(s) 116a and a touch pad area 116b the intraoral scanner is provided with a touch / force-sensitive interface capable of detecting both touch gestures, e.g. swipes, in the x- y plane and how hard the user is pressing the touch sensitive zone, i.e. detection of force in the z- direction, whereby a three-dimensional touch interface is provided.

[0091] The intraoral scanner 100 comprises a control device configured for initiating an action or operation associated with the user interaction detected by the user interface. The control device may be configured to initiate one or more actions, such as: initiating a scan, stopping a scan, navigating in a graphical user interface, selecting a menu item, acquiring a single image, proceeding to a next or previous step in a scanning workflow, undoing a previous action, initiating a fluorescence or infrared scan, interacting with the 3D representation (e.g. zoom and / or rotate), uploading the 3D representation to the cloud, etc. In some embodiments, the user interface comprises one or more mechanical buttons and / or one or more reconfigurable buttons. The control device may be configured for handling multiple substantially simultaneous detections, e.g. the user swiping with two fingers or pressing multiple force sensitive areas at once, and initiating an action or operation associated with the multiple detections.

[0092] The action or operation may also be one of another device than the intraoral scanner 100 of the 3D scanner system 10. As an example, the user interface of the intraoral scanner 100 may be used for controlling a scanning station 200 operatively connected to the intraoral scanner. The touch pad area and / or movement sensors may be translated into movement of a cursor of the Graphical User Interface, GUI, presented on the display 210 of the scanning station 200, i.e. the intraoral scanner 100 may be used as a pointer. Similarly, a tap of the user on the touch sensitive area may be translated into a selection in the GUI the same way pressing a mouse button would. When inspecting the 3D representation 20 of the scanned object 310, the touch pad area and / or movement sensors may be used by the user to perform actions such as rotating and / or zooming the 3D representation 20 displayed on a display 210 of the scanning station 200.

[0093] Fig. 4 shows a perspective view of an intraoral scanner similar to the one shown in Fig. 3. As the user interface is provided by the touch sensitive zone the outer shell can be provided as one continuous closed surface, unlike the scanners of the prior art, which were controlled by mechanical buttons requiring an electrical or mechanical connection through the shell. This provides the scanner 100 of the present disclosure with a hygienic advantage as the outer surface has fewer places where dirt may accumulate. In the shown embodiment, the external surface is provided as a smooth uninterrupted surface where the touch sensitive zone is indistinguishable from the remainder of the external surface, which for some users provides an improved aesthetical perception.

[0094] Fig. 5 shows a perspective view of another intraoral scanner similar to the one shown in Fig. 3. This embodiment differs from that of Fig. 4 in that the force sensitive area 116a is indicated by a protrusion and coloring on the external surface 112 and the touch pad area 116b is indicated by a depression in the external surface 112. These allow the user to quickly and effortlessly identify the touch sensitive zone, either by feeling the external surface 112 with the fingers or by looking at the external surface 112. In general, the touch sensitive zone may be distinguished from the remaining external surface 112, by one or more of the following: surface color, surface roughness, surface texture, surface elevation, or any combination hereof.

[0095] Fig. 6 shows a cross-sectional view of an intraoral scanner 100 of the present disclosure. In this embodiment the user interface comprises two force sensors 120 but the capacitive sensor array 122 is omitted. The touch sensitive zone is thus provided by two force sensitive areas 116a arranged at two discrete spots. Fig. 7 shows a perspective view of the intraoral scanner shown in Fig. 6. To indicate the position of the two force sensitive areas 116a, the external surface 112 comprise two depressions so that the user may locate the force sensitive areas 116a by feeling the level difference of each of the two force sensitive areas 116a relative to the surrounding external surface 112. Fig. 8 shows a cross-sectional view of an intraoral scanner 100 of the present disclosure. In this embodiment the user interface comprises the capacitive sensor array 122, while the force sensors 120 are omitted. The touch sensitive zone is thus provided by a touch pad area 116b. Fig. 9 shows a perspective view of the intraoral scanner shown in Fig. 8. To indicate the position of the touch pad area 116a, the external surface 112 comprises a depression so that the user may locate the touch pad area 116b by feeling the level difference of the touch pad area 116b relative to the surrounding external surface 112.

[0096] Fig. 10a shows a cross-sectional view of an intraoral scanner 100 of the present disclosure. In this embodiment the user interface comprises both the capacitive sensor array 122 and two force sensors 120, so that the touch sensitive zone comprises both a touch pad area 116b and two force sensitive areas 116a. The capacitive sensor array 122 and the two force sensors 120 are arranged overlapping at the internal surface whereby a touch pad area 116b with two force sensitive areas 116a is provided. Alternatively, as shown in Fig. 10b, an array of force sensors 120 could be provided overlapping the capacitive sensor array 122 so that the entire or most of the touch pad area 116b would also be force sensitive, i.e. a three dimensional touch pad area. Fig. 11 shows a perspective view of the intraoral scanner shown in Fig. 10a and Fig. 10b. To indicate the position of the touch pad area 116a, the external surface 112 comprises a depression so that the user may locate the touch pad area 116b by feeling the level difference of the touch pad area 116b relative to the surrounding external surface 112.

[0097] Fig. 12 shows a cross / sectional schematic view of the touch sensitive zone. As disclosed above, the outer shell 110 comprises an external surface 112 and an internal surface 114. At the touch sensitive zone, a capacitive sensor array 122 and a number of force sensors 120 are arranged at the internal surface 114 whereby the capacitive sensor array 122 and the force sensors 120 may detect bending of the outer shell cause by the force applied by a user touching the external surface 112 of the touch sensitive zone.

[0098] The outer shell 110 may be made from a plastic material comprising polycarbonate, Acrylonitrile Butadiene Styrene (ABS), or a combination of these two. To ensure that the force sensor(s) 120 and / or capacitive sensor array 122 can reliably detect the user’s touch, the outer shell 110 should have a thickness between 0.25 - 2.1 mm at the touch sensitive zone and be made from a material with a tensile modulus between 1800-2800 MPa, preferably 2000-2600 MPa, more preferably about 2300 MPa, when measured with the ISO 527-1 ,-2 standard at test conditions of 1 mm / min.

[0099] Fig. 13 shows a cross / sectional schematic view of the touch sensitive zone similar to that of Fig. 12. In this embodiment, the outer shell 110 is thinner at touch sensitive zone to help the user locate it and to provide increased sensitivity of the capacitive sensor array 122 and force sensors 120 due to the reduced thickness of the outer shell 110 between the external and internal surfaces 112; 114. Figs. 14-16 show cross / sectional schematic views of how the force sensor(s) may be mounted at the internal surface of the touch sensitive area.

[0100] Fig. 14 shows a pre-loaded force sensor mounted between the outer shell 110 and a substrate, in this case also provided by the outer shell 110. Pre-loading the force sensor(s) may provide linear operation of the gage, tension measurement and facilitate the creation of the necessary friction that allows for shear force measurements. To pre-load the force sensor 120, an elastic device 124, e.g. a spring or a piece of rubber, is arranged between the force sensor 120 and the internal surface 114 or between the force sensor 120 and the substrate so the force sensor and the elastic device 124 become tensioned between the substrate and the internal surface 114. To fixate the elastic device and force sensor, an adhesive, e.g. a pressure sensitive adhesive (PSA), may be used to attach them to the internal surface.

[0101] Fig. 15 shows a pseudo-pre-loaded force sensor 120 where the force sensor 120 is suspended from a printed circuit board (PCB). To provide the pre-loading, the elastic device 124 is tensioned inbetween the PCB and the internal surface 114 whereby the force sensor 120 feels the force generated by the compression of the elastic device 124. Fig. 16 shows a suspended force sensor 120 without pre-loading. In such embodiments, the force sensor is suspended from the internal surface 114 by use of an adhesive. The force sensor 120 may either be directly attached to the internal surface 114, or the force sensor 120 may be connected to a PCB, via solder bombs as shown, and the PCB may in turn be attached to the internal surface 114.

[0102] Fig. 17 shows three different examples of shapes for one-dimensional touch pad areas. Such touch pad areas may be about a finger in width and be configured for detecting a moving touch in one dimension only, e.g. a forward and backwards swipe. Such touch pad interfaces are easy to operate as they remain simple and intuitive for users to use, while still providing more interaction possibilities than traditional push buttons. Fig. 18 shows four different examples of shapes for two-dimensional touch pad areas 116b. Such touch pad areas 116b may be more complex to use, but for advanced users they will provide an increased amount of control due to the increased number of interactions one can perform with the two-dimensional touch pad.

[0103] The use of the terms "first", "second", "third" and "fourth", "primary", "secondary", "tertiary" etc. does not imply any particular order, but are included to identify individual elements. Moreover, the use of the terms "first", "second", "third" and "fourth", "primary", "secondary", "tertiary" etc. does not denote any order or importance, but rather the terms "first", "second", "third" and "fourth", "primary", "secondary", "tertiary" etc. are used to distinguish one element from another. Note that the words "first", "second", "third" and "fourth", "primary", "secondary", "tertiary" etc. are used here and elsewhere for labelling purposes only and are not intended to denote any specific spatial or temporal ordering. Furthermore, the labelling of a first element does not imply the presence of a second element and vice versa.

[0104] It is to be noted that the word "comprising" does not necessarily exclude the presence of other elements or steps than those listed. It is to be noted that the words "a" or "an" preceding an element do not exclude the presence of a plurality of such elements.

[0105] It should further be noted that any reference signs do not limit the scope of the claims, that the exemplary embodiments may be implemented at least in part by means of both hardware and software, and that several "means", "units" or "devices" may be represented by the same item of hardware.

[0106] It should be appreciated that reference throughout this specification to "one embodiment" or "an embodiment" or “an aspect” or features included as “may” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. Furthermore, the particular features, structures or characteristics may be combined as suitable in one or more embodiments of the disclosure. The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects.

[0107] Although embodiments and features have been shown and described, it will be understood that they are not intended to limit the claimed invention, and it will be made obvious to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the claimed invention. The specification and drawings are, accordingly to be regarded in an illustrative rather than restrictive sense. The claimed invention is intended to cover all alternatives, modifications, and equivalents.

[0108] Further details

[0109] Embodiments of the invention are disclosed in the following list of enumerated items:

[0110] 1. A 3D scanner system (10) for scanning an object of an oral cavity (310) of a patient (300) during a scanning session, the scanner system (10) comprising:

[0111] - an intraoral scanner (100) comprising:

[0112] ■ one or more cameras configured for capturing images of the object for the provision of image data, an outer shell made in one piece, the outer shell having an internal surface and an external surface, and

[0113] ■ a user interface configured for controlling one or more processes of the scanning session, wherein the user interface comprises one or more force sensor(s) and / or a capacitive sensor array arranged at the internal surface to provide a touch sensitive zone of the outer shell, the one or more force sensor(s) and / or the capacitive sensor array being configured for detecting a user touching the external surface of the touch sensitive zone,

[0114] - one or more processors configured to generate a 3D representation of the object based on the image data.

[0115] 2. The 3D scanner system according to item 1 , wherein each of the one or more force sensor(s) is / are configured for detecting two or more levels of force applied by a user touching external surface of the touch sensitive zone.

[0116] 3. The 3D scanner system according to item 1 or 2, wherein at least one force sensor of the one or more force sensor(s) is / are arranged over or under the capacitive sensor array.

[0117] 4. The 3D scanner system according to any of the previous items, wherein the 3D scanner system comprises a feedback device configured for outputting a feedback signal based on a detection of the touch sensitive zone being touched by the at least one of the one or more force sensor(s) and / or by the capacitive sensor array.

[0118] 5. The 3D scanner system according to item 4, wherein the strength of the feedback signal is based on the level of force detected by at least one of the one or more force sensor(s).

[0119] 6. The 3D scanner system according to item 4 or 5, wherein the feedback signal comprises one or more of the following: a haptic signal, an audio signal, a visual signal, or a combination hereof.

[0120] 7. The 3D scanner system according to any of items 4-6, wherein the feedback device is comprised by the intraoral scanner.

[0121] 8. The 3D scanner system according to item 7, wherein the feedback signal is a tactile signal, and wherein the feedback device is configured for generating the tactile signal at a position of the touch sensitive zone where the detection of the touch sensitive zone being touched was detected. 9. The 3D scanner system according to any of the previous items, wherein the exterior surface of the touch sensitive zone comprises one or more protrusion(s).

[0122] 10. The 3D scanner system according to any of the previous items, wherein the exterior surface of the touch sensitive zone comprises one or more depression(s).

[0123] 11 . The 3D scanner system according to any of the previous items, wherein the exterior surface of the touch sensitive zone comprises one or more color marking(s) at the external surface.

[0124] 12. The 3D scanner system according to any of items 9-11 , wherein the one or more protrusion(s), one or more depression(s), and / or one or more color marking(s) is / are arranged at one or more position(s) of the touch sensitive zone where a force sensor of the one or more force sensor(s) and / or the capacitive sensor array is / are arranged at the internal surface.

[0125] 13. The 3D scanner system according to any of items 9-12, wherein the one or more protrusion(s), one or more depression(s), and / or one or more color marking(s) indicate(s) a position of the touch sensitive zone, at which position a force sensor of the one or more force sensor(s) and / or the capacitive sensor array is / are configured to detect touch.

[0126] 14. The 3D scanner system according to any of the previous items, wherein the capacitive sensor array is arranged on a flexible PCB.

[0127] 15. The 3D scanner system according to any of the previous items, wherein the capacitive sensor array is configured to detect touch based on capacitive coupling through self-capacitance between an electrode and a ground plane and / or on capacitive coupling through mutual capacitance between two or more electrodes.

[0128] 16. The 3D scanner system according to any of the previous items, wherein each of the one or more force sensors are provided by one or more of a strain gauge sensor, a piezo-electric sensor, a capacitive sensor, an ultrasound sensor, or any combination hereof.

[0129] 17. The 3D scanner system according to any of the previous items, wherein the touch sensitive zone is arranged on a top side of the intraoral scanner.

[0130] 18. The 3D scanner system according to any of the previous items, wherein the touch sensitive zone is a curved surface.

[0131] 19. The 3D scanner system according to item 18, wherein the touch sensitive zone is a convex surface. The 3D scanner system according to item 18, wherein the touch sensitive zone is a concave surface. The 3D scanner system according to any of the previous items, wherein the touch sensitive zone comprises two or more discrete spots, wherein at least one force sensor of the one or more force sensor(s) is / are arranged at each of the spots. The 3D scanner system according to any of the previous items, wherein the force sensing user interface comprises two or more force sensors. The 3D scanner system according to any of the previous items, wherein the force sensing user interface comprises two force sensors. The 3D scanner system according to item 22 or 2322, wherein at least two force sensors of the two or more force sensors are arranged in a line extending substantially parallel with a longitudinal axis of the intraoral scanner. The 3D scanner system according to any of items 22-24, wherein the user interface is configured for discarding detections of the two or more force sensors that occurs substantially simultaneously. The 3D scanner system according to any of the previous items, wherein the user interface comprises a secondary interaction device. The 3D scanner system according to item 26, wherein the secondary interaction device comprises one or more movement sensors configured for detecting movement of the intraoral scanner. The 3D scanner system according to item 27, wherein the one or more movement sensors comprises one or more of the following: an accelerometer, a gyroscope, a magnetometer, or a combination hereof. The 3D scanner system according to item 27 or 28, wherein the one or more movement sensors is / are configured for detecting one or more of the following: pitch of the intraoral scanner, roll of the intraoral scanner, yaw of the intraoral scanner, or a combination hereof. The 3D scanner system according to item 27 or 29, wherein the one or more movement sensors is / are configured for detecting linear displacement of the intraoral scanner. 31. The 3D scanner system according to any of the previous items, wherein the outer shell is made of a material comprising one or more of the following, a polycarbonate, acrylonitril- butadien-styren (ABS), or a mixture hereof.

[0132] 32. The 3D scanner system according to any of the previous items, wherein the outer shell is made from a material with a tensile modulus between 1800-2800 MPa when measured with the ISO 527-1 ,-2 standard at test conditions of 1 mm / min.

[0133] List of references

[0134] 10 3D scanner system

[0135] 20 3D representation

[0136] 100 Intraoral scanner 102 Mechanical button 110 Outer shell 112 External surface 114 Internal surface 116a Force sensitive area 116b Touch pad area 118 Internal volume 120 Force sensor

[0137] 122 Capacitive sensor array 124 Elastic device 180 Hygienic tip barrier 190 Battery 200 Scanning station 210 Display 300 Patient

[0138] 310 Object of an oral cavity

Claims

Claims1. A 3D scanner system (10) for scanning an object of an oral cavity (310) of a patient (300) during a scanning session, the scanner system (10) comprising:- an intraoral scanner (100) comprising:■ one or more cameras configured for capturing images of the object for the provision of image data,■ an outer shell made in one piece, the outer shell having an internal surface and an external surface, and■ a user interface configured for controlling one or more processes of the scanning session, wherein the user interface comprises one or more force sensor(s) arranged at the internal surface to provide a touch sensitive zone of the external surface of the outer shell, the one or more force sensor(s) being configured for detecting two or more levels of force applied by a user touching external surface of the touch sensitive zone.- one or more processors configured to generate a 3D representation of the object based on the image data.

2. The 3D scanner system according to claim 1 , wherein the user interface comprises a capacitive sensor array arranged at the internal surface at the touch sensitive zone, wherein the capacitive sensor array is configured for detecting a user touching external surface of the touch sensitive zone.

3. The 3D scanner system according to claim 1 , wherein at least one force sensor of the one or more force sensors is / are arranged over or under the capacitive sensor array.

4. The 3D scanner system according to any of the previous claims, wherein the user interface comprises a feedback device configured for outputting a feedback signal based on a detection of the touch sensitive zone being touched.

5. The 3D scanner system according to claim 3, wherein the strength of the feedback signal is based on the level of force detected by at least one of the one or more force sensor(s).

6. The 3D scanner system according to any of the previous claims, wherein touch sensitive zone comprises one or more protrusion(s) and / or one or more depression(s) at the external surface, wherein at least one force sensor of the one or more force sensor(s) is / are arranged at each of the one or more protrusion(s) and / or each of the one or more depression(s).

7. The 3D scanner system according to any of the previous claims and claim 1 , wherein the capacitive sensor array is arranged on a flexible PCB.

8. The 3D scanner system according to any of the previous claims, wherein the touch sensitive zone is arranged on a top side of the intraoral scanner.

9. The 3D scanner system according to any of the previous claims, wherein the external surface of the touch sensitive zone is a curved surface.

10. The 3D scanner system according to any of the previous claims, wherein the user interface comprises two or more force sensors.11 . The 3D scanner system according to claim 10, wherein at least two force sensors of the two or more force sensors are arranged in a line extending substantially parallel with a longitudinal axis of the intraoral scanner.

12. The 3D scanner system according to claim 10 or 11 , wherein the user interface is configured for, when multiple force sensors of the two or more force sensors make simultaneous detections, comparing the force levels of the simultaneous detections, and discarding the simultaneous detections unless at least one of the simultaneous detections differs in force level from the others by more than a threshold value.

13. The 3D scanner system according to any of claims 10-12, wherein the touch sensitive zone comprises two or more discrete spots, wherein at least one force sensor of the one or more force sensor(s) is / are arranged at each of the spots.

14. The 3D scanner system according to any of the previous claims, wherein the user interface is configured for discarding detections of the one or more force sensor(s), when the detected force is below an activation threshold.

15. The 3D scanner system according to any of the previous claims, wherein each of the one or more force sensor(s) is / are configured for detecting a first level of force between about 0.1 to about 0.3 N applied by a user touching external surface of the touch sensitive zone, and for detecting a second level of force between about 0.3 to about 0.6 N applied by a user touching external surface of the touch sensitive zone.

16. The 3D scanner system according to any of the previous claims, wherein the thickness of the outer shell at the touch sensitive zone is between 0.25 - 2.1 mm.

Images