Multi-camera palm recognition device

Abstract

The utility model provides a multi-camera palm recognition device. The multi-camera palm recognition device comprises a base; the plurality of camera groups are respectively arranged at different positions of the base, each camera group comprises an infrared camera and an RGB camera, the optical axes of the infrared camera and the RGB camera in the same group are parallel, and the infrared camera and the RGB camera are respectively vertical to different preset palm planes. According to the scheme, the limitation of traditional single-view-angle palm recognition is well solved, the applicability of palm recognition is improved, the palm posture capable of being adopted by a user is more flexible, the use experience of the user is improved, and the recognition effect is also guaranteed through double shooting in the camera set.

Description

Technical Field

[0001] The present application relates to the technical field of biometric identification, and in particular to a multi-camera palm recognition device. Background Art

[0002] Biometric technology authenticates identity by detecting unique physiological or behavioral characteristics of the human body. It has the advantages of being difficult to copy, not needing to be carried around, and being easy to use. With these unique advantages, the technology has been widely used in many fields such as attendance, access control, health care, and consumption. Among them, palm vein and palm print recognition has the characteristics of liveness detection and strong anti-counterfeiting, and its security and recognition accuracy are higher than traditional body surface feature recognition technology. However, this type of recognition equipment has strict requirements on the position and angle of the palm. If the palm is tilted, not in the appropriate center position, or is too far or too close, the image quality will be affected, thereby reducing the recognition accuracy. Therefore, a palm recognition device with lower requirements for the placement of the user's palm and better experience is needed. Utility Model Content

[0003] The purpose of the present application is to solve at least one of the above-mentioned technical defects, especially the problem that the palm recognition device in the prior art has high requirements on the placement of the user's palm and poor user experience.

[0004] The present application provides a multi-camera palm recognition device, comprising: a base; a plurality of camera groups, which are respectively arranged at different positions of the base, each camera group comprising an infrared camera and an RGB camera, and the optical axes of the infrared camera and the RGB camera in the same group are parallel and respectively perpendicular to different preset palm planes.

[0005] In one embodiment, the optical axes in different camera groups are converging.

[0006] In one embodiment, the multiple camera groups include at least one pair of symmetrical groups, and the two camera groups in the same symmetrical group are symmetrically arranged on the base.

[0007] In one embodiment, the angle between the optical axes of two camera groups in the same symmetric group satisfies Wherein, A is the angle, H is the distance between two camera groups in the same symmetry group, and L is the distance from the convergence center to the line connecting the two camera groups in the same symmetry group.

[0008] In one of the embodiments, the multi-camera palm recognition device also includes a ranging module and a control module; the ranging module is connected to the control module and is used to detect the distance between the object to be recognized and the multi-camera palm recognition device; the control module is connected to each camera group and is used to control each camera group to capture an image when the distance is within a set distance range.

[0009] In one embodiment, the distance measuring module is arranged at the center of the base.

[0010] In one embodiment, the distance measurement module includes infrared distance measurement and laser distance measurement.

[0011] In one of the embodiments, the multi-camera palm recognition device further includes a plurality of infrared fill light modules, each of which is arranged around the plurality of camera groups.

[0012] In one of the embodiments, the multi-camera palm recognition device further includes a plurality of RGB fill light modules, each of which is arranged around the plurality of camera groups.

[0013] In one embodiment, the wavelength of the infrared camera includes 850nm or 940nm.

[0014] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0015] This solution proposes a multi-camera palm recognition device, the core structure of which includes a base and multiple camera groups distributed at different positions of the base, each camera group consisting of an infrared camera and an RGB camera. The infrared camera is used to collect palm vein distribution images, and the RGB camera obtains palm surface texture images, and the information of the two complements each other. The optical axes of the infrared and RGB cameras in the same camera group are parallel, and the optical axes of different camera groups are perpendicular to different preset palm planes, so as to adapt to the scanning of different palm postures. This solution has better solved the limitations of traditional single-view palm recognition and improved the applicability of palm recognition. The palm postures that users can adopt are more flexible, which improves the user experience. The dual cameras in the camera group also ensure the recognition effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 This is a schematic diagram of the structure of a multi-camera palm recognition device in one embodiment of the present application;

[0018] Figure 2 This is a schematic diagram of the arrangement of a camera group in one embodiment of the present application;

[0019] Figure 3 This is a schematic diagram of the structure of a multi-camera palm recognition device in another embodiment of the present application;

[0020] Figure 4 This is a schematic diagram of the structure of a multi-camera palm recognition device in another embodiment of the present application;

[0021] Figure 5 This is a schematic diagram of the angle of the camera group in the multi-camera palm recognition device in one embodiment of the present application;

[0022] Figure 6 This is a schematic diagram of the angle of the camera group in the multi-camera palm recognition device in another embodiment of the present application;

[0023] Description of the drawings: 10 - camera group, 110 - infrared camera, 120 - RGB camera, 20 - ranging module, 30 - infrared fill light module, 40 - RGB fill light module. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0025] 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.

[0026] In the description of the embodiments of the present utility model, it should be noted that if the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like are used to indicate an orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or are the orientation or positional relationship in which the product is usually placed when in use, they are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, if the terms "horizontal", "vertical", "overhanging" and the like are used, it does not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the embodiments of the present application, "multiple" means at least 2.

[0027] This application provides a multi-camera palm recognition device, see Figure 1, including a base and multiple camera groups 10. The base is the installation platform of the entire device, and the modules required by the device are all arranged on the base. The device is provided with at least two camera groups 10, which are respectively arranged at different positions of the base. Each camera group 10 includes an infrared camera 110 and an RGB camera 120. Among them, the infrared camera 110 is used to detect the distribution of palm veins, and the RGB camera 120 is used to detect the distribution of palm prints. The positions of the infrared camera 110 and the RGB camera 120 in the same camera group 10 can be interchanged. The device can combine palm veins and palm prints for identity recognition at the same time. The vein pattern is highly unique and random, and is one of the most reliable biometric identification features, while the palm print can complement the palm vein information to enhance the verification effect.

[0028] The multiple camera groups 10 provided in this embodiment are used to respectively face a palm posture of the user. Specifically, the palm recognition device in the traditional technology is only provided with one camera module, which requires that the user's palm plane must be perpendicular to the optical axis of the camera module in order to capture the clearest image, which also puts forward strict requirements on the user's palm posture. In contrast, the present embodiment provides multiple camera groups 10, each for corresponding to a palm posture of the user, thus giving the user more choices in palm posture. Therefore, the optical axes of the infrared camera 110 and the RGB camera 120 in the same group are parallel. By setting the inclination angle between the camera module and the base, the optical axis of the camera module can be made perpendicular to a preset palm plane. The preset palm plane can be the palm plane corresponding to the high-frequency posture adopted by the user when scanning. For example Figure 1 In the multi-camera palm recognition device shown, a camera group 10 is set on the left and right, respectively, so as to cope with the scenario where the user often deflects to the left and right when scanning. In this way, no matter whether the palm is tilted to the left or right, there is a camera module that can collect palm prints and palm veins at a relatively straight angle. The specific number of camera modules and the corresponding tilt angles of the camera modules can be set according to the cost of the device, the user's usage habits, etc.

[0029] This solution proposes a multi-camera palm recognition device, the core structure of which includes a base and a plurality of camera groups 10 distributed at different positions of the base, and each camera group 10 is composed of an infrared camera 110 and an RGB camera 120. The infrared camera 110 is used to collect the distribution image of the palm veins, and the RGB camera 120 obtains the palm surface texture image, and the information of the two complements each other. The optical axes of the infrared and RGB cameras 120 in the same camera group 10 are parallel, and the optical axes of different camera groups 10 are respectively perpendicular to different preset palm planes, so as to adapt to the scanning of different palm postures. This solution has better solved the limitations of traditional single-view palm recognition, improved the applicability of palm recognition, and the palm postures that users can adopt are more flexible, which improves the user experience. The dual cameras in the camera group 10 also ensure the recognition effect.

[0030] In one of the embodiments, the optical axes in different camera groups 10 are converging. This embodiment proposes to arrange the optical axes of the infrared and RGB cameras 120 inside each camera group 10 in a converging shape. The converging layout here does not require all optical axes to converge at the same point in space. It is only necessary for the optical axes of all camera groups 10 to pass through the target area, and the target area is the position where the human hand is completely facing the multi-camera palm recognition device at an appropriate distance. Generally, the size of the target area can be obtained based on the size of the user's palm and a reasonable expansion margin is set. From the center of the multi-camera palm recognition device, the target area is moved to a preset distance perpendicular to the direction of the base, and the position of the target area can be determined in space. Just ensure that the optical axes of all camera groups 10 pass through the target area. This is because when the user is scanning, the user's palm is tilted to a certain extent in different directions based on the target area. As long as it is ensured that the optical axis can pass through the target area, the camera group 10 will definitely correspond to a posture that the user may use. Through the reasonable setting of multiple camera groups 10, it can be ensured that the user can perform accurate scanning at most angles. For example Figure 2 As shown, Figure 2 In the figure, the square represents the camera group 10, the dotted line represents the optical axis, and the black solid line represents the projection of the target area. Figure 2 On the left side, the optical axes of the camera group 10 are converging. Figure 2 The optical axes of the two camera groups 10 on the right cannot pass through the target area, and thus are divergent.

[0031] In one embodiment, the plurality of camera groups 10 include at least one pair of symmetrical groups, and the two camera groups 10 in the same symmetrical group are symmetrically arranged on the base. It can be understood that in order to better cover the palm gestures, the camera groups 10 can be arranged symmetrically. Figure 1As shown, there are two camera groups 10, which are symmetrically distributed with the center of the base as the symmetry point, and the optical axes are deflected toward the middle of the base, in a converging shape. This structure can cope with the palm posture that is often tilted to the left or right. Figure 3 As shown, there are three camera groups 10, one of which is set at the center of the base, and the other two camera groups 10 are symmetrically distributed up and down with the center of the base as the symmetric point, and the optical axes are deflected toward the middle of the base. This structure can cope with the palm posture that is often upward or tilted upward. Figure 4 As shown, there are four camera groups 10 in total, of which two camera groups 10 are symmetrically distributed left and right with the center of the base as the symmetry point. The other two camera groups 10 are symmetrically distributed up and down with the center of the base as the symmetry point. And the optical axes of these four camera groups 10 are all deflected toward the middle of the base. This structure can cope with the palm posture that is often upward, upward, left or right tilted.

[0032] In one embodiment, the angle between the optical axes of two camera groups 10 in the same symmetric group satisfies Wherein, A is an angle, H is a distance between two camera groups 10 in the same symmetric group, and L is a distance from a convergence center to a line connecting two camera groups 10 in the same symmetric group.

[0033] It can be understood that the convergence center here is the point at a preset distance from the center of the base. Generally, the distance between the user's hand and the center of the base is within the range with the preset distance as the midpoint. The convergence center can represent the position of the user's palm. This embodiment is to ensure that all symmetric groups can converge to the same convergence center. This design has the best scanning effect. Figure 1 For structures in Figure 5 , the preset distance is 20 cm, and the distance between the two camera groups 10 is 7 cm, so the angle A is calculated to be 21°. Figure 3 and Figure 4 For structures in Figure 6 , it can be calculated that angle A is 44°.

[0034] In one embodiment, the multi-camera palm recognition device further includes a distance measurement module 20 and a control module. The distance measurement module 20 is connected to the control module and is used to detect the distance between the object to be recognized and the multi-camera palm recognition device. The control module is connected to each camera group 10 and is used to control each camera group 10 to perform image acquisition when the distance is within a set distance range.

[0035] It can be understood that the purpose of introducing the distance measurement module 20 is to determine the distance between the object to be identified (such as a palm) and the device, so as to decide whether to start the imaging process. In addition, turning on the camera group 10 for a long time is also likely to cause energy waste and affect the life of the camera group 10. Therefore, only when the object to be identified enters the set distance range, the control module will control each camera group 10 to start working, and the rest of the time each camera group 10 will be in a dormant state. Each camera group 10 can be synchronously collected, and the collected image is transmitted back to the control module for further processing.

[0036] In one embodiment, the distance measuring module 20 is arranged at the center of the base. The distance measuring module 20 is arranged so that the distance from the object to be identified to the entire device can be measured more accurately, thereby avoiding the visual angle deviation when it is placed on one side. The center position is less likely to be blocked by the surrounding camera group 10 or other components than the corner position, which is conducive to ensuring a clear sight line for ranging.

[0037] In one embodiment, the distance measurement module 20 includes infrared distance measurement and laser distance measurement. Infrared distance measurement and laser distance measurement are currently more common optical distance measurement methods. Among them, laser distance measurement has higher accuracy, but is expensive. It can be reasonably selected according to the accuracy requirements and product costs. Infrared distance measurement and laser distance measurement generally adopt the ToF principle, that is, the time required for the test light to fly to the object and then reflect back, and the distance is calculated based on the time and the speed of light.

[0038] In one embodiment, the multi-camera palm recognition device further includes a plurality of infrared fill light modules 30 , and each infrared fill light module 30 is disposed around the plurality of camera groups 10 .

[0039] It is understandable that under natural light, there may be a problem of poor shooting effect. Therefore, in this embodiment, multiple infrared fill light modules 30 are provided for fill light. The infrared fill light module 30 can be an infrared LED, and the infrared light emitted by it is consistent with the wavelength of the infrared camera 110. The infrared fill light module 30 is arranged around the multiple camera groups 10, so that the infrared camera 110 in each camera group 10 has the opportunity to be filled with light. Specifically, there can be 4 infrared fill light modules 30, which are respectively arranged at the upper left, upper right, lower left and lower right positions. Appropriate auxiliary light sources can compensate for the dark areas of imaging and obtain high-quality images that are uniform, bright and low-noise.

[0040] In one embodiment, the multi-camera palm recognition device further includes a plurality of RGB fill light modules 40 , each of which is disposed around the plurality of camera groups 10 .

[0041] It is understandable that under natural light, there may be a problem of poor shooting effect. Therefore, in this embodiment, multiple RGB fill light modules 40 are provided for fill light. The RGB fill light module 40 can be a white light or a three-color light LED. The RGB fill light module 40 is arranged around multiple camera groups 10, so that the RGB camera 120 in each camera group 10 has the opportunity to be filled with light. Specifically, the infrared fill light module 30 can be arranged in succession on a rectangular outline, and the camera groups 10 are all located inside the rectangular outline. Appropriate auxiliary light sources can compensate for the dark areas of the imaging and obtain high-quality images that are uniformly bright and low in noise.

[0042] In one embodiment, the wavelength of the infrared camera 110 includes 850nm or 940nm.

[0043] Near-infrared light with wavelengths of 850nm and 940nm has good transmittance to human tissues, which enables them to penetrate the surface of the skin more clearly and image the blood vessels, veins and other structures inside the human body.

[0044] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0045] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can refer to each other.

[0046] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-camera palm recognition device, characterized in that: include: Pedestal; A plurality of camera groups are respectively arranged at different positions of the base, each of the camera groups includes an infrared camera and an RGB camera, and the optical axes of the infrared camera and the RGB camera in the same group are parallel and respectively perpendicular to different preset palm planes.

2. The multi-camera palm recognition device according to claim 1, characterized in that: The optical axes in different camera groups are converging.

3. The multi-camera palm recognition device according to claim 2, characterized in that: The multiple camera groups include at least one pair of symmetrical groups, and the two camera groups in the same symmetrical group are symmetrically arranged on the base.

4. The multi-camera palm recognition device according to claim 3, characterized in that: The angle between the optical axes of the two camera groups in the same symmetric group satisfies Among them, A is the angle, H is the distance between the two camera groups in the same symmetric group, and L is the distance from the convergence center to the line connecting the two camera groups in the same symmetric group.

5. The multi-camera palm recognition device according to claim 1, characterized in that: It also includes a ranging module and a control module; The distance measuring module is connected to the control module and is used to detect the distance between the object to be identified and the multi-camera palm recognition device; The control module is connected to each of the camera groups and is used to control each of the camera groups to collect images when the distance is within a set distance range.

6. The multi-camera palm recognition device according to claim 5, characterized in that: The distance measuring module is arranged at the center of the base.

7. The multi-camera palm recognition device according to claim 5, characterized in that: The distance measurement module includes infrared distance measurement and laser distance measurement.

8. The multi-camera palm recognition device according to claim 1, characterized in that: It also includes a plurality of infrared fill light modules, each of which is arranged around the plurality of camera groups.

9. The multi-camera palm recognition device according to claim 1, characterized in that: It also includes multiple RGB fill light modules, each of which is arranged around the multiple camera groups.

10. The multi-camera palm recognition device according to claim 1, characterized in that: The wavelength of the infrared camera includes 850nm or 940nm.

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