CN212137839U

CN212137839U - Lens, three-dimensional imaging module and three-dimensional imaging equipment

Info

Publication number: CN212137839U
Application number: CN202021096910.1U
Authority: CN
Inventors: 吕键; 刘尧; 唐攀; 陈磊
Original assignee: Guangdong Launca Medical Device Technology Co ltd
Current assignee: Guangdong Launca Medical Device Technology Co ltd
Priority date: 2020-06-15
Filing date: 2020-06-15
Publication date: 2020-12-11
Anticipated expiration: 2030-06-15

Abstract

The utility model relates to a camera lens, three-dimensional imaging module and three-dimensional imaging device. The lens comprises a lens element, the lens element comprises at least two sub-lenses, the sub-lenses are in a non-rotational symmetric structure, each sub-lens comprises an effective light-passing part, the effective light-passing parts in the lens element are rotationally symmetric about the incident axis, the effective light-passing parts in the lens element are used for passing incident light beams to form mutually separated imaging pictures on the image side of the lens, and the number of the imaging pictures is equal to the number of the sub-lenses in the lens element. In the lens, the non-rotational symmetric structure can reduce the structural size of the sub-lens in the radial direction, so that two or more sub-lenses can be accommodated in one lens, at the moment, at least two imaging pictures at different angles aiming at a shot object can be obtained through the lens, the transverse size of the three-dimensional imaging system can be greatly reduced, and the system can better perform three-dimensional imaging on a narrow space.

Description

Lens, three-dimensional imaging module and three-dimensional imaging equipment

Technical Field

The utility model relates to a three-dimensional imaging technology field especially relates to a camera lens, three-dimensional imaging module and three-dimensional imaging device.

Background

In conventional three-dimensional imaging, two or more lenses are generally arranged at different angles, two-dimensional images of the same object are acquired at different angles, and two-dimensional image information between different angles is analyzed by contrast to obtain three-dimensional data. However, since such a conventional three-dimensional imaging apparatus requires a plurality of lenses to perform three-dimensional measurement, the size of the structure for mounting the lenses in the apparatus is large, and there is a large operational limitation in use.

SUMMERY OF THE UTILITY MODEL

Based on this, it is necessary to provide a lens, a three-dimensional imaging module and a three-dimensional imaging apparatus for solving the problem of how to acquire three-dimensional imaging information with a small-sized structure.

A lens barrel having an incident axis, comprising a lens element including at least two sub-lenses, the sub-lenses being of a non-rotationally symmetric structure, each sub-lens including an effective light-passing portion, any two effective light-passing portions of the lens element being rotationally symmetric about the incident axis, the effective light-passing portions of the lens element being capable of passing incident light beams to form mutually separated imaged pictures on an image side of the lens barrel, the number of the imaged pictures being equal to the number of the sub-lenses of the lens element.

In the lens barrel, compared with a general lens with a rotational symmetric structure, the non-rotational symmetric structure can reduce the structural size of the sub-lenses in the radial direction, so that two or more sub-lenses can be accommodated in one lens barrel, and at this time, at least two imaging pictures at different angles for a shot object can be obtained through the lens barrel, so that the transverse size of the three-dimensional imaging system can be greatly reduced, the three-dimensional imaging system can be designed in a small size, and the system can better perform three-dimensional imaging on a narrow space. And after terminal analysis is carried out on the characteristics of the pits, the bulges and the like in each imaging picture, three-dimensional information of the depth, the height and the like of the corresponding characteristics can be obtained.

In one embodiment, each of the sub-lenses of the lens element is split by one lens.

In one embodiment, the lens barrel includes at least two imaging units, each of the imaging units includes at least two sub-lenses arranged along the incident axis direction, and each of the sub-lenses is included in one of the lens elements.

In one embodiment, the sub-lenses in the same lens element are spaced or offset in a direction perpendicular to the incident axis.

In one embodiment, the sub-lens includes an arcuate edge, the arcuate edge of the sub-lens being distal from the incident axis.

In one embodiment, the lens satisfies any one of the following schemes:

the lens element comprises two sub-lenses, and the projection shapes of the two sub-lenses on a plane perpendicular to the incident axis are semicircular along the direction parallel to the incident axis;

the lens element comprises three sub-lenses, and the projection shapes of two sub-lenses on a plane perpendicular to the incident axis are fan-shaped and the projection shape of the other sub-lens on the plane perpendicular to the incident axis is semicircular along the direction parallel to the incident axis;

the lens element comprises four sub-lenses, and the projection shapes of the four sub-lenses on a plane perpendicular to the incident axis are fan-shaped along the direction parallel to the incident axis.

In one embodiment, each of the sub-lenses of the lens element surrounds the incident axis.

In one embodiment, any two of the sub-lenses in the lens element are rotationally symmetric about the incident axis.

In one embodiment, the lens includes apertures, the number of the apertures is the same as the number of the sub-lenses in the lens element, and in a direction parallel to the incident axis, each of the sub-lenses in the lens element overlaps with a projection of one of the apertures on a plane perpendicular to the incident axis.

In one embodiment, any two of the apertures are rotationally symmetric about the incident axis.

In one embodiment, the lens comprises two apertures, and the center connecting line of the two apertures is inclined to the center connecting line of the two sub-lenses.

In one embodiment, the apertures of each of the apertures are the same.

A three-dimensional imaging module comprises an image sensor and the lens, wherein the image sensor is arranged on the image side of the lens.

By adopting the lens, the transverse size of the three-dimensional imaging module can be effectively reduced, so that the using space of the module is expanded, and the three-dimensional imaging module can perform more efficient and flexible three-dimensional imaging on a narrow space.

In one embodiment, the number of the image sensors is one.

In one embodiment, the three-dimensional imaging module comprises a light source for illuminating a subject.

A three-dimensional imaging device comprises the three-dimensional imaging module. The three-dimensional imaging equipment can be applied to the fields of medical treatment, industrial manufacturing and the like, and can carry out efficient and flexible three-dimensional detection on a narrow space due to the fact that the adopted three-dimensional imaging module is small in transverse size. For example, when the three-dimensional imaging module is arranged in a probe of the equipment, the small size of the module can enable the size of the probe to be smaller, so that the operation flexibility of the probe in a narrow space is improved.

Drawings

FIG. 1 includes schematic diagrams of a lens system at two viewing angles according to an embodiment of the present disclosure;

FIG. 2 is a schematic distribution diagram of an image corresponding to the lens of FIG. 1;

fig. 3 is a schematic structural diagram of a three-dimensional imaging module according to an embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of a three-dimensional imaging module according to another embodiment of the present disclosure;

fig. 5 is a schematic configuration diagram of a sub-lens and an aperture in a lens according to an embodiment of the present disclosure;

FIG. 6 is a schematic distribution diagram of an image corresponding to the lens of FIG. 5;

FIG. 7 is a schematic view of a configuration of a sub-lens and an aperture in a lens according to another embodiment of the present disclosure;

FIG. 8 is a schematic distribution diagram of an image corresponding to the lens of FIG. 7;

FIG. 9 is a schematic view of a configuration of a sub-lens and an aperture in a lens according to another embodiment of the present application;

FIG. 10 is a schematic view of lens elements of a lens barrel according to another embodiment of the present application;

FIG. 11 is a schematic distribution diagram of an image frame corresponding to the lens of FIG. 10;

FIG. 12 is a schematic view of lens elements of a lens barrel according to another embodiment of the present application;

FIG. 13 is a schematic view of lens elements of a lens barrel according to another embodiment of the present application;

FIG. 14 is a schematic distribution diagram of an image frame corresponding to the lens of FIG. 13;

FIG. 15 is a schematic structural diagram of a three-dimensional imaging module according to an embodiment of the present disclosure;

fig. 16 is a schematic partial structural diagram of a three-dimensional imaging device according to an embodiment of the present application.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will be able to make similar modifications without departing from the spirit and scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

In conventional three-dimensional imaging, two or more lenses are generally arranged at different angles, two-dimensional images of the same object are acquired at different angles, and two-dimensional image information between different angles is analyzed by contrast to obtain three-dimensional data. However, such a conventional three-dimensional imaging apparatus is large in size and has a large operation limitation in use.

Referring to fig. 1, some embodiments of the present application provide a lens 10. The lens 10 has positive power and is used for converging image information of a subject onto an image forming surface 103. The lens 10 includes a lens barrel 100 and a lens element 110 having a special-shaped structure, the lens element 110 is installed in the lens barrel 100, an object end of the lens barrel 100 is opened with an entrance hole 1001, a central axis of the entrance hole 1001 is collinear with an incident axis 101 of the lens 10, an imaging surface 103 of the lens 10 is perpendicular to the incident axis 101, and the imaging surface 103 may be a photosensitive surface of the image sensor.

In these embodiments, the lens element 110 comprises two sub-lenses spaced apart from each other in a direction perpendicular to the incident axis 101, and both sub-lenses are non-rotationally symmetric, i.e. there is no axis of symmetry, so that any sub-lens can rotate around the axis of symmetry by an angle θ (0 < θ < 360 °) and still coincide with the non-rotated sub-lens. The two sub-lenses are arranged in a central symmetry with respect to the incident axis 101, and the two sub-lenses having a central symmetry relationship are identical in structure, for example, the surface shapes of the object side surfaces and the image side surfaces of the two sub-lenses are identical. In the direction parallel to the incident axis 101, the projection shapes of the two sub-lenses on the imaging surface 103 are the same semicircular, and the two sub-lenses can be spliced into a complete lens by translation in the direction perpendicular to the incident axis 101. On the other hand, the sub-lens includes a curved edge 1107, the curved edge 1107 of the sub-lens is far away from the incident axis 101, and if the two semicircular sub-lenses are spliced into a complete lens, the curved edges 1107 of the two sub-lenses will be used as effective light-passing edges of the object side surface or the image side surface of the lens.

Specifically, the two sub-lenses can be equally split by a complete lens, the splitting path passes through and is parallel to the optical axis of the lens, the cut surfaces formed by the two sub-lenses after being split are planes and keep parallel to each other, and the two split sub-lenses are arranged at intervals along the direction perpendicular to the optical axis of the lens. The complete lens has positive optical power, and the object side surface of the lens can be spherical or aspherical, and the image side surface of the lens can also be spherical or aspherical, so that when the lens is divided into two sub-lenses, the object side surface and the image side surface of each sub-lens also have corresponding surface types.

In the embodiment shown in fig. 1, each sub-lens can form one imaging unit, each imaging unit corresponds to one imaging picture, and the incident light beams can form the same number of imaging pictures as the imaging units on the imaging surface 103 of the lens 10 after being adjusted by the imaging units. Wherein each sub-lens comprises an effective light-passing part 1101, specifically, the object side surface and the image side surface of any sub-lens comprise one effective light-passing part 1101, and any two effective light-passing parts 1101 in the same lens element 110 are rotationally symmetrical with respect to the incident axis 101. For an incident light beam capable of passing through a sub-lens to form a corresponding image plane on an image plane, the region through which the incident light beam passes in the sub-lens is the effective light-passing portion 1101 of the sub-lens. In some embodiments, any two sub-lenses within the same lens element 110 are rotationally symmetric about the incident axis 101. In addition, in some embodiments, the rotational symmetry angle of two of the effective light passing portions 1101 in the same lens element 110 with respect to the incident axis 101 may be, but is not limited to, 60 °, 90 °, 120 °, 180 °. Here, when the two effective light passing portions 1101 are rotationally symmetrical by 180 ° with respect to the incident axis 101, the two effective light passing portions 1101 are symmetrical with respect to the center of the incident axis 101.

The arrangement of the interval between the sub-lenses can separate the imaging frames on the imaging plane 103, so that the system terminal can perform three-dimensional analysis on the corresponding features in the two imaging frames.

Referring to fig. 2, when the lens element 110 in the lens barrel 10 is a complete lens, the subject can form an original image 104 on the image plane 103 of the lens barrel 10 after being converged by the lens. When the lens element 110 is divided into two sub-lenses spaced apart from each other as in the above embodiment, the incident light beam will correspondingly form a new image on the image plane 103 after passing through each sub-lens, and the two new images can represent images of the same object area at different angles, wherein the original image 104 on the image plane 103 will be gradually separated into two new images as the spacing distance between the sub-lenses increases. When the two sub-lenses are translated in a direction for a certain distance and then spliced into a complete lens, the distance can be called as the spacing distance of the two sub-lenses. The separation direction of the imaged picture depends in part on the direction of the sub-lens away from the incident axis 101, for example, when the lens is divided into two sub-lenses arranged at intervals along a direction relative to the incident axis 101, with reference to an undivided whole lens, the imaged pictures corresponding to the two divided sub-lenses will be separated along the direction. When the separation distance between the sub-lenses is large enough, the two new imaging pictures are completely separated from each other and do not overlap with each other, and at the moment, a gap appears between the two new imaging pictures. And then, after terminal analysis is carried out on the characteristics such as the pits, the bulges and the like in the two imaging pictures which are arranged at intervals, three-dimensional information such as the depth, the height and the like of the corresponding characteristics can be obtained, and the terminal analysis method comprises but is not limited to a binocular distance measurement method and the like.

In the design of the above embodiment, it is only necessary to set the sub-lenses in the lens 10 at a distance in the direction perpendicular to the incident axis 101 so that two new imaging pictures are separated, and thus two imaging pictures at different angles with respect to the subject can be obtained by one lens 10. Compared with a general lens with a rotational symmetric structure, the non-rotational symmetric structure can reduce the structural size of the sub-lenses in the radial direction, so that two or more sub-lenses can be accommodated in one lens. Compared with the design with two or more lenses 10, the single lens 10 design can greatly reduce the transverse size of the three-dimensional imaging system, so that the three-dimensional imaging system can realize small-size design, and therefore, the size of the structure for mounting the lens 10 in the three-dimensional imaging device can be reduced, and the device can better perform three-dimensional imaging on a narrow space. For example, when the lens 10 is installed in a probe of an endoscope, since only one lens 10 is required to achieve three-dimensional information acquisition, the size of the probe can be effectively reduced, thereby improving the operational flexibility of the probe in a narrow space.

With continued reference to fig. 1, in some embodiments, the lens 10 includes an aperture, which may be integrally formed with the lens barrel 100. The number of apertures is the same as the number of sub-lenses in the lens element 110, and each sub-lens in the same lens element 110 corresponds to an aperture one-to-one, wherein each sub-lens and aperture together constitute an imaging unit. In a direction parallel to the incident axis 101, each sub-lens overlaps with its corresponding projection of the aperture onto the imaging plane 103. In addition, any two apertures are centrosymmetric with respect to the incident axis 101 of the lens 10, and the apertures of the apertures are the same, so that the brightness of the images formed by each imaging unit tends to be consistent, and the sizes of the images also tend to be consistent, thereby facilitating the accuracy of the terminal analysis. In addition to being arranged in a central symmetrical manner, any two apertures in some embodiments may be arranged in other rotationally symmetrical manners, the specific arrangement being determined according to the arrangement of the sub-lenses in the lens element 110. The aperture can also be used to limit the edge beam, suppress spherical aberration introduced by the edge beam, and control the depth of field of the imaged picture. In other embodiments, the diaphragm is independent from the lens barrel 100, in which case the diaphragm can be assembled together when the lens element 110 is installed in the lens barrel 100. In the embodiment shown in fig. 1, the two sub-lenses are the first sub-lens 1111 and the second sub-lens 1112 respectively, the two apertures are the first aperture 121 and the second aperture 122 respectively, the first aperture 121 is disposed on the image side of the first sub-lens 1111, the second aperture 122 is disposed on the image side of the second sub-lens 1112, a connection line between centers of the first aperture 121 and the second aperture 122 is perpendicular to the incident axis 101, and in a direction parallel to the incident axis 101, the first sub-lens 1111 overlaps with a projection of the first aperture 121 on the image plane 103, and the second sub-lens 1112 overlaps with a projection of the second aperture 122 on the image plane 103.

Referring to fig. 2 in combination, the first sub-lens 1111 and the first aperture 121 constitute a first imaging unit 1021, the second sub-lens 1112 and the second aperture 122 constitute a second imaging unit 1022, accordingly, the two separated imaging pictures are a first imaging picture 1051 and a second imaging picture 1052, respectively, the first imaging unit 1021 corresponds to the first imaging picture 1051, the second imaging unit 1022 corresponds to the second imaging picture 1052, the incident light beam enters the lens barrel 10 through the light entrance 1001 of the lens barrel 100, and forms the first imaging picture 1051 on the imaging plane 103 after the convergence is adjusted by the first imaging unit 1021, and forms the second imaging picture 1052 on the imaging plane 103 after the convergence is adjusted by the second imaging unit 1022. For a concave or convex feature structure on a shot object, corresponding images of the concave and convex in an imaging picture will have different degrees of dispersion, and the first imaging unit 1021 and the second imaging unit 1022 which are arranged at intervals can image the feature structure at different angles, so that the lens 10 also has the effect of binocular vision, and the depth information of the feature structure is obtained by performing terminal analysis on the same feature on the first imaging picture 1051 and the second imaging picture 1052, for example, analyzing the dispersion condition of the feature images and/or the separation distance of the feature images in the two pictures. By using the lens 10 in the above embodiments, three-dimensional imaging information can be reconstructed by using two-dimensional imaging information of a subject, thereby realizing three-dimensional imaging for the subject.

In other embodiments, the first stop 121 may be disposed on the object side of the first sub-lens 1111, and the second stop 122 may also be disposed on the object side of the second sub-lens 1112, and a central connection line between the first sub-lens 1111 and the second sub-lens 1112 is still perpendicular to the incident axis 101. The symmetry of the sub-lens and the aperture about the incident axis 101 is beneficial to improving the consistency of the brightness, the definition and the size of an imaging picture, and further is beneficial to the accuracy of terminal analysis.

In addition, to prevent the incident light beam outside the first sub-lens 1111 and the second sub-lens 1112 from reaching the image sensor, in some embodiments, the lens 10 further includes an optical barrier 130, the optical barrier 130 is connected between the sub-lenses in the lens element 110, and the optical barrier 130 is opaque. The light blocking plate 130 may be a metal plate or a plastic plate, and the light blocking plate 130 may be disposed perpendicular to the incident axis 101. The light blocking plate 130 may be provided with a black coating layer to prevent stray light from being formed in the lens 10 after the incident light beam is reflected by the light blocking plate 130. The light blocking plate 130 can also function to increase the mounting stability between the sub-lenses by connecting the sub-lenses.

Referring to fig. 3, the embodiment of fig. 3 provides a three-dimensional imaging module 20, the three-dimensional imaging module 20 includes an image sensor 210 and the lens 10 of the above embodiment, the image sensor 210 is disposed on the image side of the lens 10. The image sensor 210 may be a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The imaging plane 103 of the lens 10 overlaps with the photosensitive surface of the image sensor 210, and the incident axis 101 of the lens 10 is perpendicular to the photosensitive surface and passes through the center of the photosensitive surface. The light beams from the subject are converged by the lens 10 to form two mutually spaced imaging pictures on the photosensitive surface of the image sensor 210. Particularly, when the number of the image sensors 210 is one, each imaging frame can be formed on the image sensor 210, so that the transverse size of the module can be effectively controlled, and further the small-size design of the three-dimensional imaging module 20 can be realized.

The shape of the photosensitive surface on the image sensor 210 is generally rectangular, and in some embodiments, the separation direction of each sub-lens is parallel to the length direction of the photosensitive surface, and the separation distance between the sub-lenses along the direction parallel to the length direction is greater than or equal to half of the length of the photosensitive surface, thereby facilitating the formation of two separated imaging pictures on the photosensitive surface. The above-mentioned separation distance between the sub-lenses is understood to be the minimum distance between the two sub-lenses in the direction parallel to the length direction. Further, the spacing distance between the sub-lenses in the direction parallel to the length direction should be less than or equal to three-quarters of the length of the photosensitive surface, thereby preventing the problem of image quality degradation due to an excessively large spacing distance between the sub-lenses.

Above, through adopting above-mentioned camera lens 10, the transverse dimension of three-dimensional imaging module 20 can be effectively reduced to the usage space of extension module makes three-dimensional imaging module 20 can carry out the three-dimensional formation of image of more high-efficient flexibility to narrow space. It should be noted that, in addition to only one image sensor 210, two or more image sensors 210 may be disposed in the three-dimensional imaging module 20, and each image sensor 210 corresponds to one or two imaging frames.

On the other hand, in order to avoid the interference light from reaching the image plane 103, the three-dimensional imaging module 20 further includes a filter, and the filter is disposed between the lens 10 and the image sensor 210, or may be disposed on the object side of the lens 10, for example, the filter is disposed on the object side of the image sensor 210 when covering the light inlet 1001 of the lens barrel 100. The filter can be a visible light band-pass filter or an infrared band-pass filter aiming at different wave bands of working light. Generally, in a method of reconstructing a two-dimensional image into a three-dimensional image, there is a corresponding analysis method for imaging a wavelength band within a range or a specific wavelength band. When the three-dimensional imaging module 20 can carry out three-dimensional reconstruction to visible light imaging, the filter in the module can be an infrared cut-off filter to can filter out the infrared light, prevent that the infrared light from causing the interference to visible light imaging.

In some embodiments, the three-dimensional imaging module 20 includes a light source, which is fixedly disposed relative to the lens 10. The light source is used for illuminating the object, the filter is used for passing light with wavelength emitted by the light source, and the lens 10 receives the light which is irradiated to the object by the light source and reflected back, so as to form a corresponding imaging picture on the image sensor 210. Specifically, in one embodiment, when the three-dimensional imaging module 20 needs to perform imaging for a specific wavelength band (e.g., 900nm infrared light), the three-dimensional imaging module 20 may additionally provide an infrared light source to irradiate 900nm infrared light to the object, and at this time, the filter may be a narrow band pass filter for 900nm, so as to filter out incident light beams with wavelengths other than 900 nm. In other embodiments, instead of providing the optical filter, a filter film may be provided on the object-side surface and/or the image-side surface of the sub-lens to achieve the filtering effect. In addition to being able to illuminate infrared light at this wavelength, the light source in some embodiments may also illuminate infrared light at other wavelengths, or may also illuminate a monochromatic visible light.

It should be noted that the arrangement of each sub-lens and each aperture is not limited to the arrangement of the above-mentioned embodiments. Referring to fig. 4, in some embodiments, the axial direction 1102 of each sub-lens is oblique to the incident axis 101, and for each sub-lens after oblique placement, the object side surface of the sub-lens is closer to the incident axis 101 than the image side surface. When two sub-lenses are spliced into a lens, the axial direction 1102 of the sub-lens is parallel to the optical axis of the lens. In some embodiments, the included angle between the axial direction 1102 of the sub-lens and the incident axis 101 of the lens 10 is 1 ° to 20 °. The obliquely arranged sub-lenses can increase the spacing distance between the imaging frames, that is, the sub-lenses can form the spacing relation between the corresponding imaging frames by a smaller spacing distance, thereby being beneficial to further reducing the transverse size of the lens 10. In addition, by controlling the inclination angle, it is also beneficial to avoid that the area of each imaging picture with the characteristic information exceeds the imaging range of the image sensor 210 due to the overlarge interval distance between the imaging pictures. Similarly, the aperture corresponding to the sub-lens is also tilted in synchronization with the corresponding sub-lens, and the central axis of the aperture tilted together is parallel to the axial direction 1102 of the corresponding sub-lens, thereby ensuring the brightness uniformity of the image screen. The above oblique arrangement of the respective sub-lenses and the aperture can also be understood as an overall oblique arrangement of the corresponding imaging units, and when the structures of the respective imaging units are identical or nearly identical, the respective imaging units should also have a rotationally symmetrical relationship with respect to the incident axis 101 after being obliquely arranged with respect to the incident axis 101.

On the other hand, the specific setting position of the diaphragm can be varied and is not limited to the setting scheme presented in fig. 1. Comparing fig. 1 and 5, in the embodiment shown in fig. 1, the direction of the line connecting the centers of the two apertures is parallel to the direction of separation of the two sub-lenses; in the embodiment shown in fig. 5, the center connecting line of the two apertures is inclined to the center connecting line of the two sub-lenses. The position of the corresponding imaged picture will also change depending on the position of the aperture. Specifically, with reference to fig. 5 and 6, fig. 6 shows the arrangement of the imaging frames corresponding to the lens 10 in the embodiment of fig. 5, the square frame in fig. 6 shows the photosensitive surface of the image sensor 210, the separation direction between the sub-lenses is parallel to the length direction of the photosensitive surface, when the connection line direction of the center of the aperture is inclined to the separation direction of the two sub-lenses, the two imaging frames will be displaced in the direction inclined to the length direction after being separated along the length direction, that is, the two imaging frames will be arranged at intervals along the diagonal direction of the photosensitive surface, so as to improve the utilization rate of the photosensitive surface, increase the imaging intervals of the same features on the object to be shot on the imaging surface 103, and further facilitate improving the accuracy of the reconstructed three-dimensional information.

In addition to the spaced arrangement, the sub-lenses in the elements of the lens 10 can also be arranged in a staggered arrangement to obtain spaced imaged pictures. Referring to fig. 7, in some embodiments, two sub-lenses capable of being spliced into a complete lens are arranged in a staggered manner in a direction perpendicular to the incident axis 101, the two sub-lenses arranged in the staggered manner are kept in contact, and when the two sub-lenses are moved in a direction opposite to the staggered manner, the two sub-lenses can be spliced into the complete lens again. Referring also to fig. 8, with the offset arrangement, the separation distance of the two new imaged pictures will increase as the offset distance between the two sub-lenses increases, and the separation direction of the two new imaged pictures depends in part on the offset direction of the two sub-lenses. In the embodiment of the offset arrangement, when two sub-lenses are translated in a direction by a certain distance and then spliced into a complete lens, the distance can be referred to as the offset distance of the two sub-lenses.

In the embodiment of the present application, when the sub-lenses in the same lens element 110 are described as being spaced apart or offset, the sub-lenses may be referred to as being spaced apart, i.e., the spaced apart arrangement does not mean that the corresponding sub-lenses are spaced apart, but may be offset in the abutting state. The separation direction between the sub-lenses represents the spacing direction or the misalignment direction between the sub-lenses.

On the other hand, the positional relationship between the aperture and the sub-lens also determines the separation direction and separation distance of the two new imaged frames. In some embodiments, each sub-lens is configured with one aperture to form one imaging unit, and the two apertures are spaced apart in a plane perpendicular to the incident axis 101. In these embodiments, the apertures in the two imaging units have a separation distance in the direction perpendicular to the misalignment direction and the incident axis 101, and the magnitude of the separation distance will directly affect the separation distance of the two new imaging frames in this direction. Therefore, just because the first sub-lens 1111 and the second sub-lens 1112 have a misalignment distance in the misalignment direction and the corresponding first aperture 121 and second aperture 122 have a separation distance in the direction perpendicular to the misalignment direction in the embodiment of fig. 7, two new imaging frames on the imaging plane 103 have a separation distance in the directions parallel to and perpendicular to the misalignment direction, thereby showing the case of being separated along the diagonal line as shown in fig. 8.

In the embodiment shown in fig. 7, along a direction parallel to the incident axis 101, there exists a symmetry axis for the projection of the first aperture 121 and the first sub-lens 1111 on the imaging plane 103, and there also exists a symmetry axis for the projection of the second aperture 122 and the second sub-lens 1112 on the imaging plane 103, and the two symmetry axes can refer to the imaginary straight line in fig. 7, and the two symmetry axes respectively pass through the projection centers of the two apertures.

Referring to fig. 9, in other embodiments, the first aperture 121 and the second aperture 122 may also be disposed offset from the respective axes of symmetry described above. In the embodiment shown in fig. 9, as the first aperture 121 and the second aperture 122 are further away from each other in the misalignment direction, the separation distance between the corresponding first imaging picture 1051 and second imaging picture 1052 in the misalignment direction will be further increased. In these embodiments, the first aperture 121 and the second aperture 122 maintain a rotationally symmetric relationship about the incident axis 101, and the apertures of both are the same.

By implementing the spacing and offset design for the sub-lenses in the lens element 110 and adjusting the setting position of the aperture, each imaging picture in the expected arrangement and separation relationship can be flexibly obtained. In addition, the arrangement relationship between the sub-lenses and the arrangement relationship between the diaphragms are not limited to the description of the above embodiments, but all the sub-lenses that can obtain a desired image picture by the above arrangement principle should be included in the description scope of the present application.

Further, the number of sub-lenses in the lens element 110 may be three, four or more, in addition to two as presented in the above embodiments. At this time, each sub-lens is still arranged in one lens barrel, each sub-lens can be formed by cutting one lens, and each cut sub-lens is in a non-rotational symmetric structure. Compared with a plurality of lenses with complete lenses, each sub-lens in the design has a smaller radial size relative to the complete lens, so that the lens can be installed in one lens, the transverse size of a module is reduced, and the incident light beams can form separate imaging pictures after passing through the sub-lenses

Specifically, referring to fig. 10, in some embodiments, the lens element 110 includes four sub-lenses, a projection shape of the four sub-lenses on the imaging plane 103 along a direction parallel to the incident axis 101 is a fan shape, the four sub-lenses are spaced apart from each other, and the surface shapes of the four sub-lenses are uniform, a projection shape of the four sub-lenses on the imaging plane 103 along a direction parallel to the incident axis 101 is a fan shape, and the four sub-lenses are rotationally symmetric about the incident axis 101 of the lens 10, and may be specifically centrosymmetric in some embodiments. In the above, when the four sub-lenses are moved close to the incident axis 101, a complete lens can be formed by splicing. Specifically, a complete lens can be equally split into four sub-lenses, the splitting path passes through and is parallel to the central axis of the lens, then the four sub-lenses are translated by the same distance along the radial direction of the original lens, and the four sub-lenses which are moved and fixed by the lens barrel 100 belong to one lens element 110, and the lens element 110 is rotationally symmetric about the incident axis 101.

In the embodiment shown in fig. 10, the lens 10 further includes four apertures, each aperture corresponds to one sub-lens, and each group of the corresponding sub-lenses and apertures forms an imaging unit. That is, the lens 10 includes four imaging units, namely, a first imaging unit 1021, a second imaging unit 1022, a third imaging unit 1023, and a fourth imaging unit 1024, wherein the first imaging unit 1021 includes a first sub-lens 1111 and a first aperture stop 121, the second imaging unit 1022 includes a second sub-lens 1112 and a second aperture stop 122, the third imaging unit 1023 includes a third sub-lens 1113 and a third aperture stop 123, and the fourth imaging unit 1024 includes a fourth sub-lens 1114 and a fourth aperture stop 124. The imaging units are arranged at intervals and are symmetrical about the incident axis 101, and in the same imaging unit, the projections of the sub-lens and the aperture on the imaging plane 103 are overlapped. As can be seen from the above embodiment including two sub-lenses, the distance between each sub-lens and the aperture can separate the corresponding image frames, and the separation direction and distance depend on the distance direction and distance between each sub-lens and the position where each aperture is disposed.

Therefore, referring to fig. 10 and 11, the light flux from the subject within the depth of field of the lens 10 can form a clear first imaging screen 1051 on the imaging surface 103 after being adjusted by the first imaging unit 1021, can form a second imaging screen 1052 after passing through the second imaging unit 1022, can form a third imaging screen 1053 after passing through the third imaging unit 1023, and can form a fourth imaging screen 1054 after passing through the fourth imaging unit 1024. In the embodiment represented in fig. 10, the four imaging units are respectively radially symmetrically distant from the incident axis 101, and since the incident axis 101 passes through the center of the imaging plane 103, the four imaging screens will also be distant from the center of the imaging plane 103 in the direction in which the corresponding imaging unit is distant from the incident axis 101, and finally form four separate images.

Similarly, besides the interval arrangement, the adjacent sub-lenses can also be arranged in a staggered manner to realize the separation of the imaging pictures, so as to form four imaging pictures arranged at intervals.

Referring specifically to fig. 12, each of the four sub-lenses is disposed to be offset from the other two sub-lenses, and the four sub-lenses are rotationally symmetric about the incident axis 101. When the lens element 110 is rotated by 90 °, 135 ° or 180 ° around the incident axis 101, the same structure can be obtained, and the formed image is unchanged. In this embodiment, the sub-lenses arranged in a staggered manner abut against each other, so that the stability of the lens element 110 in the lens barrel 100 can also be increased.

On the other hand, the lens element 110 may also form a structure without rotational symmetry about the incident axis 101, thereby increasing the diversity of the design of the lens 10.

Referring to fig. 13 and 14, in some embodiments, the lens element 110 includes three sub-lenses, a first sub-lens 1111, a second sub-lens 1112, and a third sub-lens 1113. In a direction parallel to the incident axis 101, the projection shapes of the first sub-lens 1111 and the second sub-lens 1112 on the imaging surface 103 are the same fan shape, and the projection shape of the third sub-lens 1113 on the imaging surface 103 is a semicircle shape, wherein the projection area of the third sub-lens 1113 is the sum of the projection areas of the first sub-lens 1111 and the second sub-lens 1112. The first sub-lens 1111, the second sub-lens 1112 and the third sub-lens 1113 may be split from a complete lens, and the splitting path may refer to a dotted straight line in fig. 13. The three divided sub-lenses are respectively radially translated by the same distance with respect to the incident axis 101 to be fixed in the lens barrel 100, thereby forming one lens element 110. Accordingly, the lens 10 further includes three apertures, namely a first aperture 121, a second aperture 122 and a third aperture 123. Specifically, in order to maintain uniformity of depth of field and brightness of the image, the apertures of the first aperture 121, the second aperture 122, and the third aperture 123 are the same in some embodiments.

The first sub-lens 1111 and the first aperture stop 121 form a first imaging unit 1021, the second sub-lens 1112 and the second aperture stop 122 form a second imaging unit 1022, and the third sub-lens 1113 and the third aperture stop 123 form a third imaging unit 1023. Referring to fig. 14, the light beam from the subject within the depth of field of the lens 10 can form a clear first image-forming picture 1051 on the image-forming plane 103 after being adjusted by the first image-forming unit 1021, a second image-forming picture 1052 after passing through the second image-forming unit 1022, and a third image-forming picture 1053 after passing through the third image-forming unit 1023. Referring to fig. 13, for comparison, when a conventional lens is disposed in the lens 10, the optical axis of the conventional lens is made collinear with the incident axis 101 of the lens 10 and passes through the center of the imaging plane 103, and the incident beam is imaged by the lens 10 as a single original image 104 at the center of the imaging plane 103 as shown in fig. 14. In the embodiment shown in fig. 13, the three imaging units are radially symmetrically away from the incident axis 101, and since the incident axis 101 passes through the center of the imaging plane 103, the three imaging frames will also be away from the center of the imaging plane 103 in the corresponding directions, and finally form three separate images.

The above embodiments are mainly described about the case where one lens element 110 is provided in the lens barrel 10. Further, however, in addition to providing one lens element 110, the lens barrel 10 in some embodiments may also provide at least two lens elements 110, and a corresponding number of imaged pictures on the imaging surface 103 can be obtained. The number of lens elements 110 in the lens 10 may be two, three, four, five, or more, and the lens elements 110 are sequentially arranged in the direction of the incident axis 101. In these embodiments, the lens 10 still includes a lens barrel 100, and each lens element 110 is disposed in the lens barrel 100. The sub-lenses of each lens element 110 can be divided into different lens elements, and for a lens 10 with more than two lens elements 110, the structure of the lens 10 can be regarded as being divided equally by a lens group that can be practically applied in a product, including but not limited to a telephoto lens group, a wide-angle lens group, a macro lens group, and the like.

In the embodiment of the present application, the number of sub-lenses in each lens element 110 is the same. Each sub-lens of the lens element 110 is in a corresponding relationship with one sub-lens of the other lens element 110, and each group of sub-lenses in the corresponding relationship constitutes one imaging unit. In the direction parallel to the incident axis 101, there is an overlap of the projections of the sub-lenses in the same imaging unit on the imaging plane 103. In particular, in some embodiments, any two adjacent sub-lenses in any imaging unit can be arranged at intervals from each other, or a cemented structure can also be formed.

It should be noted that, in some embodiments, each sub-lens in at least one lens element 110 is coated with a light-shielding film, the light-shielding film is disposed on an object side surface and an image side surface of the sub-lens, and a light-transmitting region is respectively reserved on the object side surface and the image side surface of the sub-lens, and a region of the object side surface and a region of the image side surface of the sub-lens corresponding to the light-transmitting region are the effective light-transmitting portions 1101 of the corresponding sub-lens, at this time, the size of the effective light-transmitting portions 1101 can control the brightness and the depth of field of an imaging screen, and the distance between the effective light-transmitting portions 1101 on different sub-lenses can also play a.

In other embodiments, the lens 10 may also be provided with apertures to achieve the above effect, where the number of apertures is the same as the number of sub-lenses in the lens element 110, and the apertures correspond to one another. In these embodiments, each imaging unit comprises an aperture. In the direction parallel to the incident axis 101, there is an overlap of the projections of the sub-lenses and the aperture stop in the same imaging unit onto the imaging plane 103.

Referring to fig. 15 in particular, in an embodiment of the present application, the lens 10 includes five lens elements 110, each lens element 110 includes two sub-lenses, namely a first sub-lens 1111 and a second sub-lens 1112, the first sub-lens 1111 and the second sub-lens 1112 are equally split from a complete lens, and the shape of the sub-lenses and the separation direction of the sub-lenses from the incident axis 101 can refer to the embodiment shown in fig. 1. In this embodiment, the first sub-lens 1111 and the second sub-lens 1112 in any one lens element 110 can be re-spliced into a complete lens after being linearly translated along the direction perpendicular to the incident axis 101. The lens 10 further includes a first aperture 121 and a second aperture 122, the first aperture 121 corresponds to each of the first sub-lenses 1111, the second aperture 122 corresponds to each of the second sub-lenses 1112, and along a direction parallel to the incident axis 101, projections of each of the first sub-lenses 1111 and the first aperture 121 on the imaging plane 103 overlap, and projections of each of the second sub-lenses 1112 and the second aperture 122 on the imaging plane 103 overlap. The first aperture stop 121 and the five first sub-lenses 1111 collectively form a first imaging unit 1021, and the second aperture stop 122 and the five second sub-lenses 1112 collectively form a second imaging unit 1022. The first aperture 121 may be disposed between the first sub-lens 1111 closest to the image side and the image sensor 210, or the first aperture 121 may be disposed between any two first sub-lenses 1111, or may be disposed on the object side of the first sub-lens 1111 farthest from the image sensor 210, and the second aperture 122 is similarly disposed. It should be noted that, in these embodiments, the first imaging unit 1021 and the second imaging unit 1022 should be symmetric with respect to the incident axis 101, so as to ensure that the brightness, the depth of field, and the size of the corresponding imaged frames tend to be consistent.

In the embodiment shown in fig. 15, each group of semicircular lens groups can be used as one imaging unit by integrally splitting one five-piece lens group into two equal semicircular lens groups in the radial direction. The five-lens group can be a macro lens group, so that excellent imaging can be obtained under the condition that the shooting distance is short, particularly the imaging definition in narrow spaces (such as oral cavities, intestinal tracts and the like) can be improved, and the accuracy of three-dimensional reconstruction under short-distance shooting can be improved.

Referring collectively to fig. 2, the incident light beam will form a first imaged picture 1051 on the imaging plane 103 after being conditioned by the first imaging unit 1021, and the incident light beam will form a second imaged picture 1052 on the imaging plane 103 after being conditioned by the second imaging unit 1022. The direction of the interval between the first imaging picture 1051 and the second imaging picture 1052 depends on the direction of the interval between the first imaging unit 1021 and the second imaging unit 1022, and also depends on the positions where the first aperture 121 and the second aperture 122 are disposed. The separation distance between the first imaging screen 1051 and the second imaging screen 1052 depends on the separation distance between the first imaging unit 1021 and the second imaging unit 1022, and also depends on the arrangement positions of the first aperture 121 and the second aperture 122.

In some embodiments, referring to the embodiment shown in fig. 5, the first imaging unit 1021 and the second imaging unit 1022 may also be disposed obliquely to the incident axis 101 in such a manner that the axial directions 1102 of the first imaging unit 1021 and the second imaging unit 1022 are oblique to the incident axis 101, and at this time, the sub-lens on the object side of the imaging unit is closer to the incident axis 101 than the sub-lens on the image side.

Similarly, in addition to the first sub-lens 1111 and the second sub-lens 1112 being spaced apart from each other, the first sub-lens 1111 and the second sub-lens 1112 may be disposed in a staggered arrangement, such as the embodiment shown in fig. 7, but the first sub-lens 1111 and the second sub-lens 1112 in each lens element 110 should be moved along a same direction and distance to form a staggered arrangement, and the first sub-lens 1111 and the second sub-lens 1112 in the staggered arrangement can be kept in contact. Meanwhile, the position of the aperture can be controlled to further separate the imaged pictures. The arrangement of the aperture can be referred to the embodiment presented in fig. 7 and 9.

On the other hand, each lens element 110 may include two sub-lenses, as shown in fig. 10 or fig. 13, that is, each lens element 110 includes three, four or more sub-lenses, but it should be ensured that the number of the sub-lenses in each lens element 110 is the same, each sub-lens in any lens element 110 forms a corresponding relationship with one sub-lens in the other lens elements 110, each group of the corresponding sub-lenses forms an imaging unit, and the number of the separated imaging frames is equal to the number of the imaging units.

In the above embodiments, each sub-lens in the same lens element 110 can be cut from a single lens.

In other embodiments, each sub-lens may be prepared separately, but it should be ensured as much as possible that the effective light-passing portions of any two sub-lenses in the same lens element 110 should be rotationally symmetric about the incident axis 101 of the lens 10 when each sub-lens is mounted in the lens barrel 100. Specifically, in one embodiment, the lens element 110 includes a first sub-lens 1111 and a second sub-lens 1112, and the first sub-lens 1111 and the second sub-lens 1112 are disposed symmetrically with respect to the incident axis 101, so that the same spatial distribution structure can be obtained every 180 ° of rotation of the lens element 110 around the incident axis 101.

Of course, the number of the sub-lenses in some embodiments is not limited to two, and the overall structure of any two sub-lenses is not limited to the case of central symmetry about the incident axis 101, and may also be any rotational symmetry relationship or no symmetry relationship, but it should be ensured that any two effective light-passing portions 1101 in the same lens element 110 have a rotational symmetry relationship about the incident axis 101 as much as possible, so as to ensure that the definitions of the imaging pictures corresponding to each sub-lens tend to be consistent, and further improve the accuracy of the terminal analysis.

Referring to fig. 16, an embodiment of the present application further provides a three-dimensional imaging device 30, and the three-dimensional imaging device 30 may include the three-dimensional imaging module 20 in any embodiment. The three-dimensional imaging apparatus 30 may be applied to the fields of medical treatment, industrial manufacturing, and the like. Specifically, the three-dimensional imaging device 30 may be, but is not limited to, a smartphone, a tablet computer, a dental camera device, an industrial detection device, an unmanned aerial vehicle, a vehicle-mounted camera device, and the like. Due to the small transverse size of the three-dimensional imaging module 20, the three-dimensional imaging device 30 can perform efficient and flexible three-dimensional detection on a narrow space. For example, when the three-dimensional imaging module 20 is disposed in a probe of an apparatus, the small size characteristics of the module allow the probe to be made smaller, thereby increasing the flexibility of operation of the probe in narrow spaces.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A lens barrel having an incident axis, comprising a lens element, wherein the lens element comprises at least two sub-lenses, the sub-lenses are in a non-rotational symmetric structure, each sub-lens comprises an effective light-passing portion, any two effective light-passing portions in the lens element are rotationally symmetric about the incident axis, the effective light-passing portions in the lens element can pass incident light beams to form mutually separated imaging pictures on an image side of the lens barrel, and the number of the imaging pictures is equal to the number of the sub-lenses in the lens element.

2. The lens barrel as claimed in claim 1, wherein each of the sub-lenses of the lens element is split by one lens.

3. The lens barrel according to claim 1, comprising at least two imaging units, each of the imaging units comprising at least two of the sub-lenses arranged along the incident axis direction, each of the sub-lenses being included in one of the lens elements.

4. The lens barrel according to claim 1, wherein the sub-lenses in the same lens element are disposed at intervals or offset in a direction perpendicular to the incident axis.

5. The lens barrel according to claim 1, characterized in that any one of the following solutions is satisfied:

6. The lens barrel as claimed in claim 1, wherein any two of the sub-lenses of the lens element are rotationally symmetric about the incident axis.

7. The lens barrel as claimed in claim 1, comprising apertures, the number of which is the same as the number of said sub-lenses in said lens element, each of said sub-lenses in said lens element overlapping with a projection of one of said apertures on a plane perpendicular to said axis of incidence, respectively, in a direction parallel to said axis of incidence.

8. The lens barrel according to claim 1, wherein the lens element is disposed in the lens barrel, the lens barrel has an entrance aperture formed at an object end, and a central axis of the entrance aperture is collinear with an incident axis of the lens barrel.

9. A three-dimensional imaging module comprising an image sensor and the lens of any one of claims 1-8, wherein the image sensor is disposed on an image side of the lens.

10. A three-dimensional imaging apparatus comprising the three-dimensional imaging module of claim 9.