阅读说明：本技术 口内扫描成像系统及其成像方法 (Intraoral scanning imaging system and imaging method thereof ) 是由 不公告发明人 于 2020-12-28 设计创作，主要内容包括：本发明提供了一种口内扫描成像系统及其成像方法。口内扫描成像系统包括：第一成像组件,用于获取牙齿的初始三维图像,包括第一成像光源和与所述第一成像光源对应设置的接收器；第二成像组件,用于获取所述牙齿的多个偏振三维图像,包括第二成像光源以及与所述第二成像光源对应设置的偏振成像单元；图像处理组件,所述图像处理组件用于接收所述初始三维图像和多个所述偏振三维图像,并对其进行处理以获取所述牙齿的精细三维图像。本发明的口内扫描成像系统通过设置两组成像组件,分别获取初始三维图像和偏振三维图像可通过偏振三维图像对初始三维图像进行修正,有效提升了牙齿的精细三维图像的成像精度。(The invention provides an intraoral scanning imaging system and an imaging method thereof. An intraoral scanning imaging system comprising: the first imaging assembly is used for acquiring an initial three-dimensional image of a tooth and comprises a first imaging light source and a receiver arranged corresponding to the first imaging light source; the second imaging assembly is used for acquiring a plurality of polarized three-dimensional images of the tooth and comprises a second imaging light source and a polarized imaging unit which is arranged corresponding to the second imaging light source; an image processing component for receiving the initial three-dimensional image and the plurality of polarized three-dimensional images and processing them to obtain a refined three-dimensional image of the tooth. According to the intraoral scanning imaging system, the two groups of imaging assemblies are arranged, the initial three-dimensional image and the polarization three-dimensional image which are respectively obtained can be corrected through the polarization three-dimensional image, and the imaging precision of the fine three-dimensional image of the tooth is effectively improved.)

1. An intraoral scanning imaging system, comprising:

the first imaging assembly is used for acquiring an initial three-dimensional image of a tooth and comprises a first imaging light source and a receiver arranged corresponding to the first imaging light source;

the second imaging assembly is used for acquiring a plurality of polarized three-dimensional images of the tooth and comprises a second imaging light source and a polarized imaging unit which is arranged corresponding to the second imaging light source;

an image processing component for receiving the initial three-dimensional image and the plurality of polarized three-dimensional images and processing them to obtain a refined three-dimensional image of the tooth.

2. An intraoral scanning imaging system according to claim 1, wherein: the intraoral scanning imaging system further comprises a housing, the first imaging assembly and the second imaging assembly are both contained in the housing, and the centers of the first imaging assembly and the second imaging assembly are both located on the center line of the housing.

3. An intraoral scanning imaging system according to claim 1, wherein: the polarization imaging unit comprises a polarization component and a polarization image acquisition component which is arranged corresponding to the polarization component.

4. An intraoral scanning imaging system according to claim 3, wherein: the number of the polarization imaging units is 1, and the centers of the polarization imaging units and the second imaging light source are both located on the central line of the shell.

5. An intraoral scanning imaging system according to claim 4, wherein: the polarization member is positioned above the polarization image acquisition member, the polarization member is rotationally connected with the polarization image acquisition member, and light rays emitted by the second imaging light source irradiate on the tooth and are collected by the polarization image acquisition member through the rotating polarization member.

6. An intraoral scanning imaging system according to claim 5, wherein: the rotating speed of the polarization component is more than or equal to 1 r/s.

7. An intraoral scanning imaging system according to claim 3, wherein: the polarization imaging units are arranged in a plurality of numbers at the same time, and the polarization imaging units are arranged in a rotation symmetry mode around the center of the second imaging light source.

8. An intraoral scanning imaging system according to claim 1, wherein: the first imaging assembly is one of a structured light 3D imaging assembly or a time-of-flight imaging assembly; the second imaging light source is any one of a polarized light source and an unpolarized light source.

9. An intraoral scanning imaging system according to claim 1, wherein: the image processing assembly comprises a control component and a display component electrically/signal-connected with the control component, and the control component is integrated in the shell and is respectively and electrically connected with the first imaging assembly and the second imaging assembly.

10. An intraoral scanning imaging method, comprising:

s1, acquiring an initial image of the tooth by adopting a first imaging assembly, and acquiring an initial three-dimensional image of the tooth;

s2, acquiring a polarization three-dimensional image of the tooth by adopting a second imaging assembly, and acquiring a plurality of polarization three-dimensional images of the tooth under different polarization angles;

and S3, carrying out pixel segmentation on the polarization three-dimensional image by taking the initial three-dimensional image as constraint, calculating a space normal vector of each pixel, and carrying out refinement processing on the initial three-dimensional image to obtain a refined three-dimensional image of the tooth.

Technical Field

The invention relates to an intraoral scanning imaging system and an imaging method thereof, belonging to the field of scanning machinery.

Background

An intraoral scanner is a three-dimensional modeling tool for teeth commonly used in the oral field. The existing intraoral scanner performs three-dimensional surface modeling on teeth based on the visible light three-dimensional imaging principle.

The current mainstream intraoral scanners use structured light imaging (i.e. projecting stripes or other shapes onto intraoral teeth), and then acquire changes of the stripes (or other shapes) through a camera or other image acquisition structures to invert the three-dimensional model of the teeth, and the imaging of the existing intraoral scanners is affected by the structure of the structured light imaging, so that the precision of the existing intraoral scanners is controlled to be 10-30 micrometers.

In fact, besides the mode of projecting stripes and collecting stripe deformation, the existing intraoral scanning imaging, a binocular imaging mode and a photon flight time mode can be subjected to optical three-dimensional modeling; however, because the features on the tooth are few and the space in the oral cavity is limited, the components of the imaging triangle during the binocular imaging process are affected, making it difficult to obtain three-dimensional modeling of the tooth using the binocular imaging method.

When the photon flight time method is used for tooth three-dimensional modeling, the imaging precision of the photon flight time method is low, so that the imaging precision requirement of 10-30 micrometers cannot be met.

Meanwhile, no matter based on a structured light imaging mode, a binocular imaging mode or a photon flight time method, the method of optical three-dimensional imaging is used for imaging the teeth in the mouth, and the following defects exist: 1. the method is easily influenced by reflected light, namely if water exists on teeth, three-dimensional modeling is difficult to perform; 2. binocular imaging is not applicable due to few tooth features; both the structured light imaging mode and the photon flight time method cannot fully utilize single pixel information of the camera, and a plurality of pixels are required to be combined together for image analysis, so that the information utilization rate is low, and the integral three-dimensional imaging speed is low.

In view of the above, it is necessary to provide an intraoral scanning imaging system and an imaging method thereof to solve the above problems.

Disclosure of Invention

The invention aims to provide an intraoral scanning imaging system and an imaging method thereof.

To achieve the above object, the present invention provides an intraoral scanning imaging system, comprising: the first imaging assembly is used for acquiring an initial three-dimensional image of a tooth and comprises a first imaging light source and a receiver arranged corresponding to the first imaging light source; the second imaging assembly is used for acquiring a plurality of polarized three-dimensional images of the tooth and comprises a second imaging light source and a polarized imaging unit which is arranged corresponding to the second imaging light source; an image processing component for receiving the initial three-dimensional image and the plurality of polarized three-dimensional images and processing them to obtain a refined three-dimensional image of the tooth.

As a further improvement of the present invention, the intraoral scanning imaging system further includes a housing, the first imaging component and the second imaging component are both accommodated in the housing, and the centers of the first imaging component and the second imaging component are both located on a center line of the housing.

As a further improvement of the present invention, the polarization imaging unit includes a polarization member and a polarization image capturing member disposed in correspondence with the polarization member.

As a further improvement of the present invention, the number of the polarization imaging units is 1, and the centers of the polarization imaging units and the second imaging light source are both located on the central line of the housing.

As a further improvement of the present invention, the polarization member is located above the polarization image capturing member, the polarization member is rotatably connected to the polarization image capturing member, and the light emitted from the second imaging light source is irradiated on the tooth and collected by the polarization image capturing member through the rotating polarization member.

As a further improvement of the invention, the rotating speed of the polarization component is more than or equal to 1 r/s.

As a further improvement of the present invention, the polarization imaging unit is provided in plurality at the same time, and the plurality of polarization imaging units are disposed rotationally symmetrically with respect to the center of the second imaging light source.

As a further improvement of the present invention, the first imaging assembly is one of a structured light 3D imaging assembly or a time-of-flight imaging assembly; the second imaging light source is any one of a polarized light source and an unpolarized light source.

As a further improvement of the present invention, the image processing assembly includes a control member and a display member electrically/signal-connected to the control member, and the control member is integrated in the housing and electrically connected to the first imaging assembly and the second imaging assembly respectively.

In order to achieve the above object, the present invention provides an intraoral scanning imaging method, comprising: s1, acquiring an initial image of the tooth by adopting a first imaging assembly, and acquiring an initial three-dimensional image of the tooth; s2, acquiring a polarization three-dimensional image of the tooth by adopting a second imaging assembly, and acquiring a plurality of polarization three-dimensional images of the tooth under different polarization angles; and S3, carrying out pixel segmentation on the polarization three-dimensional image by taking the initial three-dimensional image as constraint, calculating a space normal vector of each pixel, and carrying out refinement processing on the initial three-dimensional image to obtain a refined three-dimensional image of the tooth.

The invention has the beneficial effects that: the intraoral scanning imaging system disclosed by the invention is used for simultaneously/respectively imaging the teeth by arranging the first imaging assembly and the second imaging assembly so as to respectively obtain the initial three-dimensional image and the polarized three-dimensional image of the teeth, meanwhile, the image processing assembly is used for fitting the obtained initial three-dimensional image and the polarized three-dimensional image, and the polarized three-dimensional image is further used for correcting the initial three-dimensional image so as to obtain a fine three-dimensional image, so that the fine three-dimensional image has higher imaging precision. Furthermore, because the first imaging assembly and the second imaging assembly simultaneously/respectively image the teeth, the accuracy of the finally obtained fine three-dimensional model of the teeth is improved, the imaging time of the intraoral scanning system is effectively reduced, and the method is suitable for popularization and use.

Drawings

FIG. 1 is a block diagram of the intraoral scanning imaging system of the present invention.

FIG. 2 is a schematic diagram of a preferred embodiment of the intraoral scanning imaging system of FIG. 1.

FIG. 3 is a schematic diagram of another preferred embodiment of the intraoral scanning imaging system of FIG. 1.

Fig. 4 is a schematic flow chart of the intraoral scan imaging method of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

It should be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and/or processing steps closely related to the aspects of the present invention are shown in the drawings, and other details not closely related to the present invention are omitted.

In addition, it is also to be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Referring to fig. 1 to 3, an intraoral scanning imaging system 100 according to the present invention is shown. The intraoral scanning imaging system 100 comprises a housing 1, a first imaging component 2 and a second imaging component 3 accommodated in the housing 1, and an image processing component 4 electrically/signal-connected to the first imaging component 2 and the second imaging component 3, wherein the first imaging component 2 and the second imaging component 3 are used for acquiring a three-dimensional image of intraoral teeth, and further acquiring a fine three-dimensional image of the teeth by fitting the image processing component 4.

In the present invention, the housing 1 includes a first housing 11 and a second housing (not shown), and the first housing 11 and the second housing are engaged with each other to form an accommodating space (not shown) for accommodating the first imaging component 2 and the second imaging component 3. Further, the first imaging assembly 2 and the second imaging assembly 3 are located at the same end of the housing 1, and the other end of the housing 1 away from the first imaging assembly 2 and the second imaging assembly 3 forms a holding portion 12, so that a user can conveniently hold and further image the teeth in the mouth through the first imaging assembly 2 and the second imaging assembly 3.

The first imaging assembly 2 is used for acquiring an initial three-dimensional image of a tooth, in the invention, the initial three-dimensional image is acquired by fitting a plurality of initial images acquired by the first imaging assembly 2, and further, the acquisition of the initial three-dimensional image further comprises smoothing the images after the plurality of initial images are fitted, so as to improve the imaging precision of the initial three-dimensional image.

In the invention, the center of the first imaging component 2 is located on the central line of the housing 1 in the length direction, and the housing 1 is provided with the through hole for accommodating the first imaging component 2, so that the housing 1 can conveniently drive the first imaging component 2 to extend into the oral cavity to image the teeth.

Further, the first imaging assembly 2 comprises a first imaging light source 21 and a receiver 22 arranged corresponding to the first imaging light source 21; specifically, the first imaging light source 21 is used for emitting light to the tooth and reflecting the light on the surface of the tooth, and the reflected light reflected by the surface of the tooth is received by the receiver 22 and transmitted to the image processing assembly 4 through the receiver 22 for imaging so as to obtain an initial three-dimensional image of the tooth.

In a preferred embodiment of the present invention, the first imaging component 2 is a structured light 3D imaging component in signal/electrical connection with the image processing component 4, and preferably, the first imaging light source 21 is a laser; the receiver 22 is a CCD camera, and further, the laser 21 is arranged in a staggered manner with respect to the CCD camera 22, and the laser 21 transmits laser light to the tooth surface to form a three-dimensional image of the light stripe modulated by the tooth surface shape on the tooth surface; the three-dimensional image of the light bar can be detected by the CCD camera 22 at another position, thereby obtaining a two-dimensional distorted image of the light bar; specifically, the degree of distortion of the two-dimensional distorted image of the light bar depends at least on the surface shape profile (height) of the tooth. Thus, the displacement (or offset) of the two-dimensional distorted image of the light bar is proportional to the tooth surface height, the kink represents a change in the tooth plane, and the discontinuity indicates a physical gap in the tooth surface; the image coordinates of the two-dimensional distorted image of the light bars can reproduce the three-dimensional shape contour of the tooth surface, obtain an initial image of the tooth surface, and then obtain an initial image photo of the tooth through one or more initial image fits.

In another preferred embodiment of the present invention, the first imaging device 2 is a Time of Flight (TOF) imaging device in signal/electrical connection with the image processing device 4, and the first imaging light source 21 is a light pulse generator; the receiver 22 is a depth camera, and further, the light pulse generator 21 can emit continuous light pulses onto the tooth and reflect via the surface of the tooth; the depth camera 22 may then receive the light pulses reflected from the tooth surface, and the depth camera 22 scales the distance between/on the tooth surface by calculating the time or phase difference between the light pulse transmission and reflection to produce depth information at various locations on the tooth surface and then obtain initial images of the tooth surface, and then obtain initial image photographs of the tooth through one or more initial image fits.

The second imaging component 3 is used for acquiring a plurality of polarized three-dimensional images of the tooth, and in the invention, the polarized light irradiation angles corresponding to each polarized three-dimensional image are different, so that the shape of each surface of the tooth can be effectively represented.

In the present invention, the centers of the second imaging assembly 3 and the first imaging assembly 2 are both located on the central line of the housing 1, and the second imaging assembly 3 is located behind the first imaging assembly 2 in the extending direction of the housing 1. Specifically, the second imaging assembly 3 includes a second imaging light source 31 and a polarization imaging unit 32 disposed corresponding to the second imaging light source 31; and the housing 1 is provided with via holes for respectively accommodating the second imaging light source 31 and the polarization imaging unit 32.

The second imaging light source 31 is used to emit an imaging light source to the tooth and reflect on the surface of the tooth to be further received by the polarization imaging unit 32 to finally acquire a polarized three-dimensional model of the tooth. In a preferred embodiment of the present invention, the second imaging light source 31 is any one of a polarized light source and an unpolarized light source.

One or more polarization imaging units 32 may be disposed at the same time, the polarization imaging unit 32 includes a polarization member 321 and a polarization image capturing member 322 disposed corresponding to the polarization member 321, and the polarization member 321 is disposed on a light receiving path of the polarization image capturing member 322 for receiving the reflected light reflected by the tooth irradiated by the second imaging light source 31.

In a preferred embodiment of the present invention, there are 1 polarization imaging units 32, and the centers of the polarization imaging unit 321 and the second imaging light source 31 are located on the central line of the housing 1. Further, the polarization member 321 is located above the polarization image capturing member 322, and the polarization member 321 is rotationally connected to the polarization image capturing member 322, so that the reflected light reflected by the tooth is collected by the polarization image capturing member 322 through the rotating polarization member 321, so as to obtain the polarization three-dimensional images corresponding to different polarization light irradiation angles through the polarization image capturing member 322; preferably, the rotating speed of the polarization member 321 is greater than or equal to 1r/s, so that the collection density of the polarization three-dimensional image can be effectively improved, the initial three-dimensional image can be conveniently corrected through the plurality of polarization three-dimensional images, and the accuracy of obtaining the tooth surface shape structure can be further improved.

In another preferred embodiment of the present invention, a plurality of polarization imaging units 32 'are simultaneously disposed, and the plurality of polarization imaging units 32' are rotationally symmetrically disposed about the center of the second imaging light source 31. In the present embodiment, the polarizing member 321 'is connected to the collecting lens of the polarized image collecting member 322', and the center of the polarizing member 321 'is coaxially disposed with the center of the collecting lens of the polarized image collecting member 322'.

Further, since the plurality of polarization imaging units 32 'are rotationally symmetrically arranged about the center of the second imaging light source 31, the plurality of polarization imaging units 32' can simultaneously receive the light signals reflected from different angles on the tooth surface, and further achieve the acquisition of the polarized three-dimensional image at multiple angles. Preferably, 3 or 4 polarization imaging units 32 ' are simultaneously arranged, and when 3 polarization imaging units 32 ' are simultaneously arranged, an included angle between two adjacent polarization imaging units 32 ' is 60 degrees; when 4 polarization imaging units 32 'are arranged at the same time, the included angle between two adjacent polarization imaging units 32' is 45 degrees; of course, in other embodiments of the present invention, the included angle between two adjacent polarization imaging units 32 ' may also be other angles, and it is only necessary to ensure that the distance between each polarization imaging unit 32 ' and the second imaging light source 31 is equal, and the included angle between two adjacent polarization imaging units 32 ' is equal.

The image processing assembly 4 is adapted to receive the initial three-dimensional image acquired by the first imaging assembly 2 and the plurality of polarized three-dimensional images acquired by the second imaging assembly 3, and in particular the image processing assembly 4 is adapted to register the initial three-dimensional image and the plurality of polarized three-dimensional images. In the present invention, the image processing assembly 4 comprises a control component 41 and a display component 42 electrically/signal connected with the control component 41, in a preferred embodiment of the present invention, the control component 41 is integrated in the housing 1 and is electrically connected with the first imaging assembly 31 and the second imaging assembly 32, 32', respectively.

Further, the control component 41 may perform pixel segmentation on each polarized three-dimensional image, and the control component 41 may perform spatial normal vector calculation, and then calculate a spatial normal vector of each pixel, so as to characterize the shape of the tooth corresponding to the pixel point by the spatial normal vector, and at the same time, the control component 41 may register the initial three-dimensional image and the plurality of polarized three-dimensional images subjected to the spatial normal vector calculation and characterization, so as to correct the initial three-dimensional image by the plurality of polarized three-dimensional images subjected to the spatial normal vector calculation and characterization, so as to accurately perform fine modeling on the three-dimensional shape of each tooth, so as to obtain a fine three-dimensional image of the tooth; in fact, since the spatial normal vector of each pixel can be calculated by the control means 41 simultaneously, the speed of acquiring a fine three-dimensional image of a tooth can be increased while ensuring the accuracy of the fine three-dimensional image establishment of the tooth.

The display component 42 is used for displaying the initial three-dimensional image acquired by the first imaging component 2, the plurality of polarized three-dimensional images of the second imaging component 3, the plurality of polarized three-dimensional images after the spatial normal vector calculation and representation, and the fine three-dimensional image of the tooth, so that a user can observe various images conveniently, and meanwhile, various images can be adjusted through peripheral structures connected to the image processing component 4, such as a mouse, a keyboard, a touch control panel and other peripheral structures.

Referring to fig. 4, the present invention further provides an intraoral scanning imaging method 200 for obtaining a fine three-dimensional image of an intraoral tooth by the intraoral scanning imaging system 100, specifically, the intraoral scanning imaging method 200 includes:

s1, acquiring an initial image of the tooth by adopting the first imaging component 31;

s2, acquiring a polarization three-dimensional image of the tooth by adopting the second imaging component 32, 32', and acquiring a plurality of polarization three-dimensional images of the tooth under different polarization angles;

and S3, carrying out pixel segmentation on the polarization three-dimensional image by taking the initial three-dimensional image as constraint, calculating a space normal vector of each pixel, and carrying out refinement processing on the initial three-dimensional image to obtain a refined three-dimensional image of the tooth.

The following description section will be described in detail with respect to steps S1 to S3.

Step S1 specifically includes:

s11, acquiring a plurality of initial images of the tooth through the first imaging assembly 31;

and S12, performing registration fitting on the plurality of initial images, and performing smoothing processing on the images after registration fitting to obtain initial three-dimensional images of the teeth.

Further, step S2 specifically includes the following steps:

the polarization members 321, 321 'are in a first state, and the polarization image acquisition members 322, 322' acquire a plurality of first polarization three-dimensional images of the tooth;

the polarization members 321, 321 'are in the second state, and the polarization image acquisition members 322, 322' acquire a plurality of second polarization three-dimensional images of the tooth;

......

the polarization members 321 and 321' are in the Nth state, wherein N is more than or equal to 3; the polarization image acquisition components 322 and 322' acquire the N polarization three-dimensional image for a plurality of times;

the second imaging assembly 32, 32' fits and registers the first polarized three-dimensional image, the second polarized three-dimensional image, the.

Specifically, the first state, the second state, the.

Step S3 includes:

s31, selecting characteristic points of the teeth, and calibrating the characteristic points on the initial three-dimensional image and the plurality of polarization three-dimensional images;

s32, performing pixel segmentation on each polarized three-dimensional image, and performing calculation of a space surface normal vector on each pixel through the image processing assembly 4;

and S33, registering the initial three-dimensional image and the plurality of polarized three-dimensional images which are calculated and characterized by the space normal vector according to the characteristic points, and acquiring the registered three-dimensional image of the tooth.

In summary, the intraoral scanning imaging system 100 of the present invention images the tooth simultaneously/respectively by setting the first imaging component 31 and the second imaging components 32, 32' to obtain the initial three-dimensional image and the polarized three-dimensional image of the tooth respectively, and at the same time, the image processing component 4 fits the obtained initial three-dimensional image and the polarized three-dimensional image, and further corrects the initial three-dimensional image by the polarized three-dimensional image to obtain the fine three-dimensional image, so that the fine three-dimensional image has higher imaging precision. Further, since the first imaging component 31 and the second imaging components 32 and 32' simultaneously/respectively image the teeth, the accuracy of the finally obtained fine three-dimensional model of the teeth is improved, and meanwhile, the imaging time of the intraoral scanning system 100 is effectively reduced, and the method is suitable for popularization and use.

Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the present invention.