Fisheye module and panoramic camera

Abstract

The utility model relates to a fisheye module and a panoramic camera. The fisheye module comprises a panoramic imaging lens, a photosensitive part and an optical filter. The light sensing part is located on the image side of the panoramic imaging lens, and the light filter comprises a light transmitting part located between the panoramic imaging lens and the light sensing part and a light shielding part which is fixedly arranged in the center area of the light transmitting part and is smaller than the light transmitting part in size so as to carry out annular imaging on the light sensing part. The problem of low RI of the lens and the problem of inaccurate mapping distance measurement caused by stray light generated when strong light directly enters the lens are avoided, different from traditional annular imaging, the shading part is arranged in the center of the optical filter outside the panoramic imaging lens to shield light reaching the central area of the photosensitive part, meanwhile, improvement on the structure of the lens is avoided, and the imaging efficiency is improved. The manufacturing cost of the fisheye module is reduced, and the fisheye module can be popularized to various fields needing panoramic imaging technology assistance.

Description

Technical Field

[0001] The utility model relates to the technical field of panoramic camera modules, in particular to a fisheye module and a panoramic camera. Background Art

[0002] With the development of technology, various types of robots (sweeping robots, lawn mowers, service robots, etc.) have gradually entered our lives. These products require positioning, monitoring, navigation and other functions during work, and fisheye modules can meet these needs.

[0003] At present, the imaging angle of the ultra-wide-angle fisheye module can reach up to 220°~230°, and the module lenses are mainly divided into two types: panoramic imaging lenses and catadioptric imaging lenses. Panoramic imaging lenses are mostly composed of glass lenses and plastic lenses, which are low in cost, but when used in conjunction with the client, there is a problem of low lens RI leading to high ISP difficulty. In addition, in special usage scenarios, such as the need to arrange the camera upwards on a sweeping robot, stray light such as the top headlights in the house or outdoor sunlight directly enters the lens from top to bottom, resulting in an increase in the highlight area of ​​the picture, further leading to inaccurate mapping and ranging problems; the lens of the catadioptric imaging lens is made of all-glass material, and a circular image is output through a catadioptric structure. Although this can reduce the impact of stray light and reduce the processing pressure of the back-end algorithm, this type of product has complex processes, high costs, and is difficult to promote. In addition, the reflector in the lens will also generate a lot of stray light when reflecting light incident at high angles, affecting the imaging quality. Utility Model Content

[0004] Since the existing panoramic imaging lenses and catadioptric imaging lenses have the disadvantages of high stray light, low lens RI, complex process and high cost, it is difficult to promote the ultra-wide-angle fisheye module. Therefore, it is necessary to provide a fisheye module and a panoramic camera.

[0005] A fisheye module, comprising:

[0006] Panoramic imaging lens;

[0007] A photosensitive element, the photosensitive element being located on the image side of the panoramic imaging lens; and

[0008] The filter comprises a light-transmitting portion located between the panoramic imaging lens and the photosensitive element and a light-shielding portion fixedly arranged in the central area of ​​the light-transmitting portion and smaller in size than the light-transmitting portion so as to perform annular imaging on the photosensitive element.

[0009] This arrangement avoids the problem of inaccurate mapping and ranging caused by low lens RI and stray light generated by strong light directly entering the lens. Unlike traditional annular imaging, the present application sets a shading portion in the center of the filter outside the panoramic imaging lens to block the light reaching the center area of ​​the photosensitive element, while avoiding improvements to the structure of the lens itself, reducing the manufacturing cost of the fisheye module.

[0010] In an embodiment provided in the present application, the light shielding portion is located on a side of the light transmitting portion facing the photosensitive element.

[0011] With such arrangement, the light shielding portion is closer to the photosensitive element, which can avoid the problem of blurring of the inner circle of the annular image caused by reflection of light in the light-transmitting portion.

[0012] In one embodiment provided in the present application, the filter has a light-shielding area corresponding to the light-shielding portion and a light-filtering area located around the light-shielding area; the panoramic imaging lens has a first light-incoming area corresponding to the light-shielding area and a second light-incoming area surrounding the first light-incoming area and corresponding to the light-filtering area;

[0013] The viewing angle of the first light entrance area is greater than 0° and less than or equal to 200°.

[0014] With such a setting, the range of the first light-entering zone is determined by the size of the light-shielding area. The smallest light-shielding area requires that the field of view angle of the first light-entering zone is greater than 0°, that is, it can at least block the vertically incident light. The field of view angle of the first light-entering zone corresponding to the largest light-shielding area is 200°, so as to ensure that the photosensitive element can receive sufficient light.

[0015] In one embodiment provided in the present application, the field of view angle of the first light entrance area is 80°.

[0016] Such an arrangement can avoid the influence of stray light on the annular imaging as much as possible.

[0017] In one embodiment provided in the present application, the total field of view of the panoramic imaging lens is greater than or equal to 180°.

[0018] Such an arrangement can ensure that the photosensitive element receives sufficient light signals, facilitating subsequent image signal processing (ISP).

[0019] In one embodiment provided in the present application, the field of view angle of the first light entrance area is greater than 80°, and the total field of view angle of the panoramic imaging lens is greater than or equal to 180°.

[0020] Such an arrangement ensures the quality of the final annular image by reserving space for assembly errors, while also ensuring that the photosensitive element receives sufficient light.

[0021] In an embodiment provided in the present application, the light shielding portion is circular and the center of the light shielding portion coincides with the optical axis of the panoramic imaging lens.

[0022] Such an arrangement is conducive to ensuring that the annular image on the photosensitive element will not be deviated, thereby ensuring the imaging quality and facilitating subsequent image signal processing.

[0023] In one embodiment provided in the present application, the diameter of the shading portion is 0.52 mm.

[0024] With such an arrangement, in conjunction with the panoramic camera provided in this application, the annular image on the photosensitive element can have a higher quality.

[0025] In an embodiment provided in the present application, the light-shielding portion is a silk-screen located on a side of the light-transmitting portion facing the photosensitive element.

[0026] Such an arrangement reduces the thickness of the filter element, while also facilitating mass production and reducing production costs.

[0027] The present application also provides a panoramic camera, comprising:

[0028] shell;

[0029] a circuit board, the circuit board being fixedly connected to the housing; and

[0030] As for the fisheye module mentioned above, the panoramic imaging lens of the fisheye module is fixedly connected to the housing, and the photosensitive element of the fisheye module is communicatively connected to the circuit board.

[0031] The panoramic camera provided in the present application uses a new fisheye module to achieve annular imaging, which reduces production costs and is conducive to promoting this panoramic imaging method to terminal products such as sports cameras and various robots, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a structural schematic diagram of a fisheye module in one embodiment of the utility model;

[0033] Figure 2 for Figure 1 A cross-sectional view of the fisheye module shown;

[0034] Figure 3 for Figure 2 Schematic diagram of the middle filter;

[0035] Figure 4 Schematic diagram of the annular image on the photosensitive member.

[0036] Reference numerals:

[0037] 10. Panoramic imaging lens; 101. First light-entry area; 102. Second light-entry area; 20. Photosensitive element; 201. Ring image; 30. Filter; 301. Light-shielding area; 302. Light-filtering area; 31. Transparent part; 32. Light-shielding part; 40. Housing; 50. Circuit board. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0039] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0041] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0043] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0044] With the development of technology, various types of robots (sweeping robots, lawn mowers, service robots, etc.) have gradually entered our lives. These products require positioning, monitoring, navigation and other functions during work, and fisheye modules can meet these needs.

[0045] At present, the imaging angle of the ultra-wide-angle fisheye module can reach up to 220°~230°, and the module lens is mainly divided into two types: panoramic imaging lens and catadioptric imaging lens. Panoramic imaging lenses are mostly composed of glass lenses and plastic lenses, which are low in cost, but when used in conjunction with the client, there is a problem that the low RI of the lens leads to high difficulty in image signal processing (ISP). Low lens RI means that the brightness of the surrounding area of ​​the image is lower than that of the central area of ​​the image, which further leads to high difficulty in image signal processing (ISP). In specific scenarios, such as the need to arrange the camera upwards in a sweeping robot, stray light such as the top headlights in the house or outdoor sunlight directly enters the lens from top to bottom, resulting in an increase in the highlight area of ​​the picture, further leading to the problem of inaccurate mapping and ranging; the lens of the catadioptric imaging lens is made of all-glass material, and a ring image is output through a catadioptric structure. Although this can reduce the impact of stray light and reduce the processing pressure of the back-end algorithm, this type of product has complex processes, high costs, and is difficult to promote. In addition, the reflector in the lens will also generate a large amount of stray light when reflecting light incident at a high angle, affecting the imaging quality.

[0046] Based on this, it is necessary to provide a fisheye module and a panoramic camera that can avoid stray light interference and have low manufacturing cost.

[0047] See also Figures 1 to 4 , Figure 1This is a schematic diagram of the structure of a fisheye module in one embodiment of the utility model. Figure 2 for Figure 1 The cross-sectional view of the fisheye module shown, Figure 3 for Figure 2 A schematic plan view of the filter 30, Figure 4 Schematic diagram of an annular image 201 on a photosensitive member 20. A fisheye module provided in the present application includes a panoramic imaging lens 10, a photosensitive member 20 and a filter 30. The photosensitive member 20 is located on the image side of the panoramic imaging lens 10, and the filter 30 includes a light-transmitting portion 31 located between the panoramic imaging lens 10 and the photosensitive member 20 and a light-shielding portion 32 fixedly arranged in the central area of ​​the light-transmitting portion 31 and smaller in size than the light-transmitting portion 31 to perform annular imaging on the photosensitive member 20, thereby avoiding the problem of low lens RI and direct strong light affecting mapping and ranging. Specifically, when the RI value of the lens is low, the brightest point of the lens is in the center, and the brightness of the edge of the picture is much lower than that of the center of the picture. Therefore, the image signal processing (ISP) is required to adjust and increase the brightness of the image at the edge, and the adjustment range is relatively large. In the present application, the brightest point of the annular image formed by blocking the brightest point of the panoramic imaging lens 10 is located in the inner circle of the annular image, and the brightness at this point is much smaller than the brightness at the center of the original image. Therefore, the brightness difference between the brightest point and the darkest point of the annular image is reduced, thereby reducing the processing pressure of the image signal processing (ISP). In addition, unlike the traditional annular imaging through a folding reflective lens, the present application sets a light shielding portion 32 at the center of the filter 30 outside the panoramic imaging lens 10 to block the light reaching the central area of ​​the photosensitive element 20, while avoiding improvements to the structure of the panoramic imaging lens 10 itself, reducing the manufacturing cost of the fisheye module, and also avoiding a large amount of stray light generated by the folding reflective lens under the influence of the internal reflector when the incident angle is high. In addition, the panoramic imaging lens 10 of the present application adopts a combination of glass lenses and plastic lenses, which not only takes into account durability but also reduces the weight of the panoramic imaging lens 10, and can also reduce the production cost of the fisheye module.

[0048] See also Figure 2 Optionally, in one embodiment provided in the present application, the light shielding portion 32 is located on the side of the light transmitting portion 31 facing the photosensitive member 20. In this way, the light shielding portion 32 is closer to the photosensitive member 20, which can avoid the problem of blurring the inner circle of the annular image 201 caused by the reflection of light in the light transmitting portion 31.

[0049] Optionally, in an embodiment provided in the present application, the filter 30 has a shading area 301 corresponding to the shading portion 32 and a filtering area 302 located around the shading area 301; the panoramic imaging lens 10 has a first light-entry area 101 corresponding to the shading area 301 and a second light-entry area 102 surrounding the first light-entry area 101 and corresponding to the filtering area 302; considering that the field of view angle range of the actual fisheye module is 220° or 230°, the field of view angle a of the first light-entry area 101 is greater than 0° and less than or equal to 200°. In other words, the range of the first light-entry area 101 is determined by the size of the shading area 301. The smallest shading area 301 requires the field of view angle a of the first light-entry area 101 to be greater than 0°, that is, it can at least block the light incident vertically. The field of view angle a of the first light-entry area 101 corresponding to the largest shading area 301 is 200°, so as to ensure that the photosensitive element 20 can receive enough light.

[0050] Specifically, in one embodiment provided in the present application, the field angle a of the first light entry area 101 is 80°. This can avoid the influence of stray light on the annular imaging as much as possible. It can be understood that this is a preferred solution provided in the present application that can avoid stray light. In other embodiments, the angle can be adaptively adjusted to meet the needs of shading and final imaging cropping.

[0051] Optionally, in an embodiment provided in the present application, the total field of view of the panoramic imaging lens 10 is greater than or equal to 180°. Preferably, in an embodiment provided in the present application, the total field of view of the panoramic imaging lens 10 is 196°. After actual verification, this can ensure that the photosensitive element 20 receives sufficient light signals, facilitate subsequent image signal processing (ISP), and avoid the problem of unclear images due to weak light signals and insufficient data volume during subsequent image signal processing.

[0052] Since the filter 30 is usually fixed inside the fisheye module by gluing, generally by applying HA glue on the circuit board or the bracket, and the HA glue has a certain fluidity, there is a certain error during assembly. This error is superimposed with the setting error of the shading portion 32, which easily causes the edge position of the annular imaging to be uncertain. When the edge position is close to the central area, the stray light in the central area will still interfere with the annular image 201. Therefore, in one embodiment provided in the present application, the field of view angle a of the first light inlet area 101 is greater than 80°. Preferably, in one embodiment provided in the present application, the field of view angle a of the first light inlet area 101 is 95°, that is, the shading area 301 blocks more light, and the quality of the final annular image 201 is ensured by reserving space for assembly errors. At the same time, the total field of view angle of the panoramic imaging lens 10 is 196°, which can ensure that the photosensitive element 20 receives enough light.

[0053] Optionally, in an embodiment provided in the present application, the shading portion 32 is circular and the center of the shading portion 32 coincides with the optical axis of the panoramic imaging lens 10. This helps to ensure that the annular image 201 on the photosensitive member 20 will not be offset, ensure the imaging quality, and facilitate subsequent image signal processing. It is understandable that in this embodiment provided in the present application, the surface shape of the outermost lens of the panoramic imaging lens 10 is but not limited to a spherical or aspherical curved surface, so that the actual panoramic imaging lens can enter light and form an image within a range of 360°, ensuring the comprehensiveness of the image content, without the need for secondary shooting or multi-camera complementary shooting, which is conducive to improving imaging efficiency. In other embodiments, the shape of the outermost lens can also be a non-complete spherical surface, and the shape of the shading portion 32 also needs to be adapted thereto.

[0054] Optionally, in an embodiment provided in the present application, the diameter of the shading portion 32 is 0.52 mm. In this way, good image quality can be obtained. It is understandable that the diameter of the shading portion 32 is a preferred value used in this embodiment provided in the present application. With the panoramic camera provided in the present application, the annular image 201 on the photosensitive member 20 has a higher quality. In other embodiments, the diameter of the shading portion 32 can be adaptively adjusted according to the results of actual debugging or actual needs.

[0055] Optionally, the light shielding portion 32 is a silk screen located on the side of the light transmitting portion 31 facing the photosensitive element 20. This can reduce the thickness of the filter element, and also facilitates mass production and reduces production costs.

[0056] The present application also provides a panoramic camera, including a housing 40, a circuit board 50 and the above-mentioned fisheye module, wherein the circuit board 50 is fixedly connected to the housing 40, the panoramic imaging lens 10 of the fisheye module is fixedly connected to the housing 40, and the photosensitive element 20 of the fisheye module is communicatively connected to the circuit board 50. The annular image is cut and stretched to form a rectangular panoramic image, without rotating the lens, with high panoramic imaging efficiency and complete image content. Combined with the low-cost improvement scheme of the present application, it is conducive to promotion to more technical fields such as sports cameras and robots, thereby promoting the development of machine vision.

[0057] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0058] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A fisheye module, characterized in that: include: Panoramic imaging lens; A photosensitive element, wherein the photosensitive element is located on the image side of the panoramic imaging lens; as well as The filter comprises a light-transmitting portion located between the panoramic imaging lens and the photosensitive element and a light-shielding portion fixedly arranged in the central area of ​​the light-transmitting portion and smaller in size than the light-transmitting portion so as to perform annular imaging on the photosensitive element.

2. The fisheye module according to claim 1, characterized in that: The light shielding portion is located on a side of the light transmitting portion facing the photosensitive element.

3. The fisheye module according to claim 1, characterized in that: The filter has a light-shielding area corresponding to the light-shielding portion and a light-filtering area located around the light-shielding area; the panoramic imaging lens has a first light-incoming area corresponding to the light-shielding area and a second light-incoming area surrounding the first light-incoming area and corresponding to the light-filtering area; The viewing angle of the first light entrance area is greater than 0° and less than or equal to 200°.

4. The fisheye module according to claim 3, characterized in that: The viewing angle of the first light input area is 80°.

5. The fisheye module according to claim 4, characterized in that: The total field of view of the panoramic imaging lens is greater than or equal to 180°.

6. The fisheye module according to claim 3, characterized in that: The field of view angle of the first light entrance area is greater than 80°, and the total field of view angle of the panoramic imaging lens is greater than or equal to 180°.

7. The fisheye module according to any one of claims 1 to 6, characterized in that: The shading portion is circular, and the center of the shading portion coincides with the optical axis of the panoramic imaging lens.

8. The fisheye module according to claim 7, characterized in that: The diameter of the light shielding portion is 0.52 mm.

9. The fisheye module according to claim 1, characterized in that: The light shielding portion is a silk screen located on a side of the light transmitting portion facing the photosensitive element.

10. A panoramic camera, characterized in that: include: shell; A circuit board, wherein the circuit board is fixedly connected to the housing; as well as The fisheye module according to any one of claims 1 to 9, wherein the panoramic imaging lens of the fisheye module is fixedly connected to the housing, and the photosensitive element of the fisheye module is communicatively connected to the circuit board.

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