Light field lens and light field imaging system

Abstract

The present application provides a light field lens and a light field imaging system, which relate to the field of optical technology. The light field lens assembly includes: a main lens, a lens array and a relay lens array arranged in sequence; wherein the main lens is used to capture the target object and image it for the first time, and obtain an inverted image after the first imaging; the lens array is used to perform a secondary imaging on the inverted image after the first imaging, and obtain an upright secondary imaging image; the relay lens array is used to invert the secondary imaging image again and transmit it to the corresponding photosensitive area in the image sensor. Through the new imaging principle, the light field lens assembly can be an independent assembly without being bundled and packaged with the image sensor, which reduces the difficulty of implementation; in addition, it can also be combined with more imaging devices such as ordinary cameras, and its application range is wider.

Description

Technical Field

[0001] The present application relates to the field of optical technology, and in particular to a light field lens assembly, a light field lens, a light field imaging device and a system. Background Art

[0002] A light field camera is a new type of camera whose basic structure and principle are different from those of traditional cameras. A microlens array is provided in a light field camera. The microlens array is located between the main lens and the image sensor. Each microlens receives light entering through the main lens and then focuses light in different directions onto pixels at different positions under the microlens.

[0003] At present, light field cameras are generally a whole, in which the microlens array and the image sensor are usually packaged to form a whole, namely, a light field sensor. The packaging method has high precision requirements and is difficult to implement. Summary of the invention

[0004] The present application provides a light field lens assembly, a light field lens, a light field imaging device and a system, so as to realize an independent light field lens assembly, which can be separated from an image sensor, is easy to install, has low implementation difficulty, and is therefore applicable to more imaging scenarios.

[0005] In a first aspect, an embodiment of the present application provides a light field lens assembly, comprising: a main lens, a lens array, and a relay lens array arranged in sequence; wherein:

[0006] The main lens is used to capture the target object and form an image for the first time, and obtain an inverted image after the first imaging;

[0007] The mirror array is used to perform secondary imaging on the inverted image after the first imaging to obtain an upright secondary imaging image;

[0008] The relay mirror array is used to invert the secondary imaging image again and transmit it to the corresponding photosensitive area in the image sensor.

[0009] Optionally, the lens array includes M*N array-distributed microlenses, wherein M and N are both integers greater than 0;

[0010] Each microlens in the lens array is used to perform secondary imaging on the inverted image after the first imaging to obtain M*N upright secondary imaging sub-images, and the secondary imaging image includes M*N upright secondary imaging sub-images.

[0011] Optionally, the relay lens array includes M*N array-distributed microlenses, wherein M and N are both integers greater than 0;

[0012] The relay mirror array is coaxial with the center of the mirror group array, and each microlens of the relay mirror array is used to invert each of the secondary imaging sub-images again and transmit them to the corresponding photosensitive area in the image sensor.

[0013] Optionally, M and N are equal to or both are 3.

[0014] In a second aspect, an embodiment of the present application provides a light field lens, including the light field lens assembly of the first aspect;

[0015] Part or all of the light field lens assembly is arranged inside the lens housing.

[0016] Optionally, the light field lens further comprises: a relay adapter component, wherein the relay adapter component is a hollow structure;

[0017] The relay adapter assembly includes a first port and a second port; the first port is used for installation in cooperation with the lens housing, and the second port is used for installation in cooperation with the imaging device.

[0018] Optionally, the relay mirror array is disposed in the relay adapter assembly.

[0019] Optionally, a mounting interface is provided on a side of the lens housing close to the relay lens array, and the mounting interface is used to connect an imaging device.

[0020] In a third aspect, an embodiment of the present application provides a light field imaging device, comprising: the light field lens and the 2D camera of the second aspect;

[0021] When the light field lens comprises a relay adapter component, the relay adapter component comprises a first port and a second port; the first port is used for installation in conjunction with the light field lens component, and the second port is used for installation in conjunction with a 2D camera; or,

[0022] A mounting interface is provided on one side of the lens housing close to the relay lens array, and the mounting interface is used for mounting in coordination with a 2D camera.

[0023] In a fourth aspect, an embodiment of the present application provides a light field imaging system, comprising: the light field lens and imaging device of the second aspect;

[0024] The imaging device is used to perform imaging according to the image transmitted by the light field lens.

[0025] In the light field lens assembly, light field lens, light field imaging device and system provided in the embodiments of the present application, the light field lens assembly includes: a main lens, a lens array, and a relay lens array arranged in sequence; wherein the main lens is used to capture the target object and image it for the first time, and obtain an inverted image after the first imaging; the lens array is used to perform a second imaging on the inverted image after the first imaging, and obtain an upright second imaging image; the relay lens array is used to invert the second imaging image again and transmit it to the corresponding photosensitive area in the image sensor. Through the new imaging principle, the light field lens assembly can be an independent assembly without being bundled and packaged with the image sensor, which reduces the difficulty of implementation; in addition, it can also be combined with more imaging devices such as ordinary cameras, and its application range is wider. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 A schematic diagram of the structure of a light field lens assembly provided in one embodiment of the present application;

[0028] Figure 2 A schematic diagram of the structure of a lens array in a light field lens assembly provided in an embodiment of the present application;

[0029] Figure 3 A schematic diagram of the structure of a light field lens provided in one embodiment of the present application;

[0030] Figure 4 A schematic diagram of the structure of a light field lens provided in another embodiment of the present application;

[0031] Figure 5 A schematic diagram of the structure of a light field imaging device provided in one embodiment of the present application;

[0032] Figure 6 A schematic structural diagram of a light field imaging device provided in another embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] Figure 1 This is a schematic diagram of the structure of a light field lens assembly provided in one embodiment of the present application. Figure 1 As shown, the light field lens assembly includes: a main lens 01, a lens group array 02 and a relay lens array 03 arranged in sequence.

[0037] The main lens 01 is used to capture the target object and form an image for the first time, and obtain an inverted image after the first imaging.

[0038] The main lens 01 is mainly used to capture the target object to be photographed, such as Figure 1 As shown, the first imaging is completed on the primary imaging virtual surface, and an inverted image after the first imaging is obtained, that is, an inverted image of the target object is obtained. Optionally, the inverted image after the first imaging can be an inverted and reduced image of the target object.

[0039] The lens parameters of the main lens 01 are not specifically limited in this embodiment, and different lenses can be used under different requirements or different standards.

[0040] The mirror array 02 is used to perform secondary imaging on the inverted image after the first imaging to obtain an upright secondary imaging image.

[0041] The lens array 02 may include a plurality of lenses, Figure 1 The optical path transmission is carried out, and after the lens array 02 obtains the inverted image after the first imaging, a second imaging is performed on the second imaging virtual surface. The second imaging is the inverted image after the first imaging again, and then an upright second imaging image is obtained.

[0042] It should be noted that when the lens array 02 includes a plurality of micro-lenses distributed in an array, multiple imaging can be performed based on the inverted image obtained after the first imaging to obtain a plurality of sub-images.

[0043] The relay mirror array 03 is used to invert the secondary imaging image again and transmit it to the corresponding photosensitive area in the image sensor.

[0044] The relay lens array 03 is a lens combination matched and set according to preset requirements, and may also include a plurality of micro lenses distributed in an array, which transfers the secondary imaging image obtained by each lens in the lens array 02. For example, the relay lens array 03 inverts the secondary imaging image again in the optical path, obtains the inverted image, transmits it to the image sensor, and aligns the transferred image in the corresponding photosensitive area of ​​the image sensor.

[0045] Among them, the image sensor does not belong to the light field lens assembly of this embodiment. Based on this embodiment, the image sensor does not need to be packaged with the light field lens assembly and can be set in any other imaging device, such as a camera. When the light field lens assembly is used in conjunction with the camera, it only needs to receive the image transmitted by the relay lens array 03.

[0046] Optionally, refer to Figure 1 The distance between the target object and the main lens 01 is recorded as "object distance S", the distance between the main lens 01 and the primary imaging virtual surface is recorded as "image distance S'", the distance between the primary imaging virtual surface and the lens array 02 is recorded as "lens array object distance T", the distance between the lens array 02 and the secondary imaging virtual surface is recorded as "lens array image distance T'", the distance between the secondary imaging virtual surface and the relay lens array 03 is recorded as "relay lens object distance U", and the distance between the relay lens array 03 and the image sensor is recorded as "relay lens image distance U'". These distance values ​​are not specifically limited in the present embodiment and can be flexibly adjusted according to the camera, target object, environment, other equipment factors, shooting factors, etc.

[0047] In this embodiment, the light field lens assembly includes: a main lens, a lens array, and a relay lens array arranged in sequence; wherein the main lens is used to capture the target object and perform a first imaging to obtain an inverted image after the first imaging; the lens array is used to perform a second imaging on the inverted image after the first imaging to obtain an upright second imaging image; the relay lens array is used to invert the second imaging image again and transmit it to the corresponding photosensitive area in the image sensor. Through the new optical path and new imaging principle, the light field lens assembly can be an independent assembly without being bundled and packaged with the image sensor, and the image is transmitted to the image sensor by the relay lens assembly, which reduces the difficulty of implementation; in addition, it can also be combined with more imaging devices such as ordinary cameras, and its application range is wider.

[0048] In an optional implementation, the lens array 02 may include M*N array-distributed microlenses, where M and N are both integers greater than 0. M and N may be equal or unequal, and are set according to specific imaging requirements, which are not limited here. For example, M and N may both be 2, 3, 4 or 5.

[0049] Specifically, based on Figure 1In the optical path shown, each microlens in the lens array 02 is used to perform secondary imaging on the inverted image after the first imaging, and M*N upright secondary imaging sub-images can be obtained, that is, the secondary imaging image includes M*N upright secondary imaging sub-images.

[0050] These secondary imaging sub-images may be upright sub-images corresponding to the target object at different viewing angles.

[0051] Correspondingly, the relay lens array 03 is used to acquire and transfer the secondary imaging sub-image, and the relay lens array 03 may also include M*N array-distributed microlenses, wherein M and N are both integers greater than 0. M and N may be equal or unequal, and are set according to specific imaging requirements, and are not limited here. For example, M and N may both be 2, 3, 4 or 5, etc.

[0052] It should be noted that the micro lenses in the embodiments of the present application may all be convex lenses, but the invention is not limited thereto.

[0053] In an optional implementation, the number and arrangement of microlenses in the relay lens array 03 may be consistent with those in the lens group array 02 . In the optical path, each microlens in the relay lens array 03 corresponds to a microlens in the lens group array 02 .

[0054] Correspondingly, the relay lens array 03 is coaxial with the center of the lens array 02, and each microlens of the relay lens array 03 is used to invert each of the secondary imaging sub-images again and transmit them to the corresponding photosensitive area in the image sensor. That is, the image sensor will obtain M*N inverted sub-images of the target object at different viewing angles.

[0055] It should be noted that the lenses used in the relay mirror array 03 and the lens group array 02 may be different. In this embodiment, the lens type and parameters are not limited in this embodiment and can be selected according to the specific light field lens requirements.

[0056] Optionally, M and N may be equal in this application.

[0057] Figure 2 A schematic diagram of the structure of a lens array in a light field lens assembly provided in an embodiment of the present application is shown in FIG. Figure 2 As shown, with M and N both being 3, a lens array 02 consisting of 9 microlenses is shown.

[0058] Correspondingly, the relay mirror array 03 also includes an array of 9 micro lenses, which is opposite to the mirror group array 02.

[0059] Optionally, the image sensor may obtain inverted sub-images of the target object at 9 different viewing angles, and the resolution of each inverted sub-image is 1 / 9 of the original sensor.

[0060] certainly, Figure 2 It is only a schematic diagram of the structure, and there is no restriction on the number, parameters and arrangement of microlenses.

[0061] Furthermore, the present application example also provides a light field lens, including a lens housing and the above-mentioned light field lens assembly.

[0062] Optionally, the lens housing is a hollow structure, and part or all of the light field lens assembly is disposed inside the lens housing. For example, the main lens, the lens array, and the relay lens array are sequentially arranged and fixed in the lens housing.

[0063] Figure 3 A schematic diagram of the structure of a light field lens provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, a mounting interface 102 is provided on one side of the lens housing 101 of the light field lens near the relay lens array, and the mounting interface 102 is used to connect an imaging device. The structure of the mounting interface 102 can match the interface of the connectable imaging device, and is not specifically limited here.

[0064] Figure 4 A schematic diagram of the structure of a light field lens provided in another embodiment of the present application is shown in FIG. Figure 4 As shown, the light field lens further includes: a relay adapter component 04. The relay adapter component 04 is a hollow structure to facilitate light transmission.

[0065] Optionally, the relay adapter assembly 04 includes: a first port 401 and a second port 402. The first port 401 is used to be installed in conjunction with the lens housing 101, and the second port 402 is used to be installed in conjunction with the imaging device.

[0066] It should be noted that the first port 401 and the second port 402 may be threaded interfaces or snap-on interfaces, etc. This embodiment does not impose any specific limitation, and they may be matched with the lens housing 101 and the imaging device.

[0067] Optionally, for an embodiment in which part of the light field lens assembly is disposed inside the lens housing, the relay lens array may be disposed inside the relay adapter assembly 04 , opposite to the lens group array inside the lens housing 101 .

[0068] Figure 5 A schematic diagram of the structure of a light field imaging device provided in an embodiment of the present application is shown in FIG. Figure 5 As shown, the light field imaging device includes the light field lens 501 and the 2D camera 502 in the above embodiment.

[0069] Referring to the above embodiment, if the light field lens 502 is Figure 4When the relay adapter assembly is included, the first port 401 is used to be installed in conjunction with the light field lens 501 , and the second port 402 is used to be installed in conjunction with the 2D camera 502 .

[0070] Figure 6 A schematic diagram of the structure of a light field imaging device provided in another embodiment of the present application is shown in FIG. Figure 6 As shown, the light field imaging device includes the light field lens 601 and the 2D camera 602 in the above embodiment.

[0071] Referring to the above embodiment, if the light field lens 601 refers to Figure 3 As shown, a mounting interface is provided on one side of the lens housing close to the relay lens array, and the mounting interface is used for mounting in conjunction with a 2D camera.

[0072] In the specific implementation, the structure of the light field lens is not Figure 5 , Figure 6 It can be installed and used in conjunction with a normal 2D camera in different ways.

[0073] The 2D camera may be provided with an image sensor, and the photosensitive area corresponding to the image sensor may receive the image transmitted by the relay mirror array for further imaging processing. In the embodiment of the present application, 3D imaging may also be achieved by combining a 2D camera with a light field lens, which is a breakthrough.

[0074] It should be noted that, in the present application, the light field lens can be an independent product, and the light field lens and the camera can be connected in the manner of the above embodiment, as long as the interface and flange distance (such as Figure 5 , Figure 6 As shown in the figure, and the image sensor size in the 2D camera matches the light field lens, then this light field lens can be applied to all such 2D cameras. The problem of high-precision packaging of the microlens array and the camera sensor has been solved. At the same time, in terms of selection, this light field lens with 3D imaging function can be used as an ordinary camera lens, making selection very easy. On the other hand, for different 2D cameras (different pixel sizes and image resolutions, etc.), there is no need to adjust the aperture of this light field lens to match the camera, which also solves the aperture matching problem for traditional light field cameras.

[0075] Furthermore, the light field lens provided in the embodiment of the present application is not limited to use with a camera, but can be used with different types of imaging devices.

[0076] In this embodiment, a light field imaging system is also provided, including the light field lens and imaging device in the above embodiment. The imaging device is not limited to other imaging devices such as cameras and video cameras, and can be used to perform imaging based on the image transmitted by the light field lens.

[0077] Optionally, the imaging device includes an image sensor to receive images transmitted by the relay mirror array.

[0078] The accompanying drawings of this embodiment can be referred to Figure 5 , Figure 6 The connection mode shown in the figure replaces the 2D camera with an imaging device, and the drawings are not repeated here. Similarly, the light field imaging system may include a relay adapter component or not, and the connection mode between the relay adapter component and the imaging device is different.

[0079] Optionally, the interface of the imaging device, the flange distance (such as Figure 5 , Figure 6 Similar to the above-mentioned embodiments, the new light field lens is adopted in the embodiments of the present application, which greatly improves the applicable scenarios and is no longer limited by the high-precision packaging of the microlens array and the image sensor.

[0080] The above description is only the preferred embodiment of the present application, and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. The above description is only the preferred embodiment of the present application, and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A light field lens, characterized in that: It comprises a lens housing and a light field lens assembly; part or all of the light field lens assembly is arranged inside the lens housing; The light field lens assembly comprises: a main lens, a lens array, and a relay lens array arranged in sequence; The main lens is used to capture the target object and perform a first imaging to obtain an inverted image after the first imaging; the lens array is used to perform a second imaging on the inverted image after the first imaging to obtain an upright second imaging image; each microlens in the lens array is used to perform a second imaging on the inverted image after the first imaging to obtain M*N upright second imaging sub-images, and the second imaging image includes M*N upright second imaging sub-images; The mirror array includes M*N array-distributed microlenses, and the relay mirror array includes M*N array-distributed microlenses, wherein M and N are both integers greater than 0, and both M and N are 3; the number and arrangement of the microlenses in the relay mirror array are consistent with those in the mirror array, and in the optical path, each microlens in the relay mirror array corresponds to a microlens in the mirror array; The relay mirror array is used to invert the secondary imaging image again and transmit it to the corresponding photosensitive area in the image sensor; the relay mirror array is coaxial with the center of the lens group array, and each microlens of the relay mirror array is used to invert each secondary imaging sub-image again and transmit it to the corresponding photosensitive area in the image sensor, and the image sensor will obtain 9 inverted sub-images of the target object at different viewing angles, and the resolution of each inverted sub-image is 1 / 9 of that of the image sensor; The light field lens further includes a relay adapter assembly, which is a hollow structure and includes a first port and a second port, wherein the first port is used to be installed in cooperation with the lens housing, and the second port is used to be installed in cooperation with an imaging device; or a mounting interface is provided on a side of the lens housing close to the relay lens array, and the mounting interface is used to connect the imaging device; The imaging device includes the image sensor.

2. The light field lens according to claim 1, characterized in that: When the light field lens includes a relay adapter component, the relay lens array is arranged in the relay adapter component.

3. A light field imaging system, characterized in that: It comprises the light field lens and imaging device as described in any one of claims 1 to 2; the imaging device is used to perform imaging according to the image transmitted by the light field lens.

Images