CN116631015A - Handprint collection system and method - Google Patents

Abstract

The invention provides a handprint collection system and method. The handprint collection system includes: a lighting system, the lighting system includes one or more blue light sources and one or more green light sources, each light source is used to emit light toward the handprint collection area, and the handprint collection area is used to place the user's hand Part or all; one or more image acquisition devices, one or more image acquisition devices are used to collect images of the handprint collection area to obtain handprint images while the illumination system emits light to the handprint collection area; processing device, processing device It is used for processing the handprint images collected by one or more image collection devices. The applicability of the handprint collection system to different skin states can be expanded, thereby helping to take into account the collection needs of various groups of people.

Description

Handprint collection system and method

technical field

The present invention relates to the technical field of handprint collection, in particular to a handprint collection system and method.

Background technique

Handprint recognition technology is one of many biometrics. The so-called biometric identification technology refers to the technology that uses the inherent physiological or behavioral characteristics of the human body to carry out personal identification. Due to the advantages of convenience and security of biometric identification, biometric identification technology has broad application prospects in the fields of identity authentication and network security. Available biometric identification technologies include handprint (such as fingerprints, etc.), face, voiceprint, iris, etc., among which handprint is the most widely used one.

Handprint recognition technology first needs to carry out the collection of handprint. In the existing handprint collection technology, the compatibility of different groups of people is not good enough. For example, the effect of collecting handprints under various conditions such as over-dry, over-wet and shallow handprints is limited, and it is difficult to meet the collection needs of various groups of people.

Contents of the invention

In order to at least partly solve the problems existing in the prior art, a system and method for collecting handprints are provided.

According to one aspect of the present invention, a handprint collection system is provided, including: a lighting system, the lighting system includes one or more blue light sources and one or more green light sources, each light source is used to emit light toward the handprint collection area, and the handprint The fingerprint collection area is used to place part or all of the user's hand; one or more image acquisition devices, and one or more image acquisition devices are used to collect images of the hand print collection area while the lighting system emits light to the hand print collection area. The handprint image is obtained; the processing device is used for processing the handprint image collected by one or more image acquisition devices.

According to another aspect of the present invention, there is provided a handprint collection method realized by the above-mentioned handprint collection system, including: when the blue light source group emits light in a blue light-emitting scheme, and the green light source group emits light in a green light-emitting scheme, through one or A plurality of image acquisition devices collects images of the handprint collection area, so as to obtain the handprint images collected by one or more image collection devices, so that in the handprint images collected by each image collection device, at least one handprint image is in the It is collected when there is a blue light source with a luminous intensity not equal to 0 in the blue light source group, and at least one handprint image is collected when there is a green light source with a luminous intensity not equal to 0 in the green light source group; wherein, the blue The color light source group includes one or more blue light sources, and the green light source group includes one or more green light sources. The blue light source scheme is used to characterize the luminous intensity of each blue light source, and the green light source scheme is used to characterize the luminous intensity of each green light source. ;When collecting, the luminous intensity of at least one light source is not 0.

According to the handprint collection system and method of the embodiments of the present invention, the blue light source and the green light source are used together to supplement light for the image collection device when collecting the handprint image. This can expand the applicability of the handprint collection system to different skin conditions, thereby helping to take into account the collection needs of various groups of people.

A series of concepts in simplified form are introduced in the Summary of the Invention, which will be further detailed in the Detailed Description. The summary of the present invention does not mean trying to limit the key features and essential technical features of the claimed technical solution, nor does it mean trying to determine the protection scope of the claimed technical solution.

The advantages and features of the present invention will be described in detail below in conjunction with the accompanying drawings.

Description of drawings

The following drawings of the invention are hereby included as part of the invention for understanding the invention. Embodiments of the present invention and description thereof are shown in the drawings to explain the principles of the present invention. In the attached picture,

Fig. 1 shows a schematic diagram of a handprint collection system and related fingers and handprint collection areas according to one embodiment of the present invention;

Figure 2 shows a schematic diagram of a handprint collection system and related fingers and handprint collection areas according to one embodiment of the present invention;

Figure 3 shows a schematic diagram of a part of the handprint collection system according to one embodiment of the present invention;

Fig. 4 shows a schematic diagram of a partial structure of a handprint collection system and relevant fingers and handprint collection areas according to an embodiment of the present invention; and

Fig. 5 shows a schematic diagram of image acquisition and light emitting timing of a light source according to an embodiment of the present invention.

Detailed ways

In the following description, numerous details are provided in order to provide a thorough understanding of the invention. It will be appreciated, however, to those skilled in the art that the following description is merely illustrative of preferred embodiments of the invention, and that the invention may be practiced without one or more of these details. In addition, in order to avoid confusion with the present invention, some technical features known in the art are not described in detail.

In order to at least partly solve the above technical problems, an embodiment of the present invention provides a handprint collection system. The system can use the blue light source and the green light source together to supplement light (or illuminate) for the image acquisition device when the image acquisition device collects the handprint image. Supplementing light with blue light and supplementing light with green light have their own advantages and disadvantages for handprint collection under different skin conditions. At the same time, using these two light sources to supplement light can expand the applicability of the handprint collection system to different skin conditions, thereby It is conducive to taking into account the collection needs of various groups of people. Although this paper mainly uses fingerprints as an example when describing the handprint collection system or method according to the embodiment of the present invention, it can be understood that the handprint collection system according to the embodiment of the present invention is not only used for fingerprint collection of fingers, but also It can be used to collect palm prints and other similar hand prints.

According to one aspect of the present invention, a handprint collection system is provided. Fig. 1 shows a schematic diagram of a handprint collection system 100 and related fingers 200 and a handprint collection area 300 according to an embodiment of the present invention. The palmprints mentioned herein may include but not limited to fingerprints of fingers and/or palmprints of palms and the like. FIG. 1 describes the structure and working principle of a handprint collection system according to an embodiment of the present invention by taking fingerprint collection of a finger as an example.

As shown in FIG. 1 , the handprint collection system 100 may include one or more image collection devices, an illumination system and a processing device 130 . The lighting system includes one or more blue light sources and one or more green light sources, and each light source is used to emit light toward the handprint collection area 300 . The blue light sources included in the lighting system form a blue light source group, and the green light sources included in the lighting system form a green light source group. The handprint collection area 300 is used to place part or all of the user's hand, such as the finger 200 . One or more image acquisition devices are used to collect images of the handprint collection area 300 while the illumination system emits light to the handprint collection area 300 to obtain a handprint image. The processing device 130 is used for processing the handprint images collected by one or more image collection devices. It should be noted that the light source included in the lighting system described herein may be any type of light source not used for coding, including but not limited to one or more of the following: point light source, line light source, surface light source, etc. The point light source may be, for example, a light strip composed of multiple point light sources. Exemplarily, at least part of the light sources in the lighting system and one or more image capture devices are located on the same side of the handprint collection area, for example, below the handprint collection area. The light source located on the same side of the handprint collection area as one or more image collection devices may be called the main light source. As an example and not limitation, in addition to the main light source, the lighting system may also include an auxiliary light source located near the handprint collection area, so as to illuminate the handprint from a position closer to the handprint. Compared with the main light source, the auxiliary light source is closer to the center of the handprint collection area. For example, the main light source can be arranged below the handprint collection area, and the center of gravity of the auxiliary light source (which can be understood as the respective center of gravity of each light source in the auxiliary light source) can be located or approximately on the same level as the center of the handprint collection area. At least part of the light sources in the auxiliary light sources can be located at predetermined positions on both sides of the handprint collection area (the first side of the two sides corresponds to the first predetermined position, and the second side corresponds to the second predetermined position), and/or at least part of the light sources It may be located at a predetermined position near the fingertip (which may be referred to as a third predetermined position). A light source located at a predetermined position on either side of the handprint collection area can emit light toward the side of the handprint collection area. A light source located near the fingertip location may emit light toward the fingertip location. The fingertip position refers to the expected position where the user's fingertip should fall when the user places the finger or palm on the handprint collection area. It can be understood that the position of the auxiliary light source is set with the goal of illuminating the hand without affecting the imaging of the image acquisition system (for example, the auxiliary light source will not enter the imaging range of the image acquisition device). The auxiliary light sources may also contain one or more blue light sources and one or more green light sources.

Exemplarily, the handprint collection system of the embodiment of the present application can be non-contact, that is, the handprint collection area is a space, and the user can collect part or all of the hand in the handprint collection area, and there is no contact with the handprint collection area. The entity touched by the handprint. Of course, optionally, the handprint collection system can also be contact type, for example, a handprint collection system that realizes handprint collection by touching a finger with a screen running on a smart device.

FIG. 1 shows three image acquisition devices 112 , 114 and 116 . Furthermore, FIG. 1 also shows a lighting system comprising at least one blue light source and at least one green light source.

Exemplarily but not limitatively, the lighting system shown in FIG. 1 may include three light source sets corresponding to the three image acquisition devices one-to-one, each light source set includes at least one blue light source and at least one green light source, for Illumination is performed when the corresponding image acquisition device performs image acquisition.

Exemplarily, according to the difference in the relative positional relationship between the light sources in the light source set and the image acquisition device corresponding to the light source set, the light source set may be further divided into light source sub-sets. For example, the light sources in the light source set are distributed on both sides of the image acquisition device, the left light source is used as a light source sub-set, and the right light source is used as a light source sub-set. For example, in FIG. 1, a first light source set includes light source subsets 122 and 122', a second light source set includes light source subsets 124 and 124', and a third light source set includes light source subsets 126 and 126'.

It should be noted that the structure of the handprint collection system 100 shown in FIG. 1 is only an example and not a limitation of the present invention, and the handprint collection system 100 according to the embodiment of the present invention is not limited to the situation shown in FIG. 1 . For example, the number of image capture devices may be more or less than three. In addition, the number of light source subsets included in the light source set around each image acquisition device shown in FIG. 1 and the positions of the light source subsets can also be changed as required. For example, any set of light sources may also include a single subset of light sources (eg, the first set of light sources may only include subset 122 of light sources) or more than two subsets of light sources.

Exemplarily, the lighting system includes at least one light source pair, and each light source pair includes a blue light source and a green light source. This example is a preferable way to arrange the light sources. This way makes each paired blue light source and green light source as close as possible, so that the acquisition conditions of the blue channel and the green channel of the image are as close as possible to the same. It helps to improve the accuracy of subsequent handprint images obtained based on the two channels.

Exemplarily, in an embodiment where the lighting system includes one or more light source sets corresponding to one or more image acquisition devices, each light source set may include at least one light source pair, and each light source pair includes a blue light source and a green light source. In this way, it is convenient to make the imaging conditions of the blue channel and the green channel corresponding to each image acquisition device as close as possible to the same when acquiring images. For example, any subset of light sources in FIG. 1 may include a pair of light sources.

The lighting system includes at least one blue light source and at least one green light source. On this basis, the number of light sources in the lighting system can be set to any suitable number as required. If classified according to color, the light sources included in the lighting system can be divided into a blue light source group and a green light source group. The number of blue light sources included in the blue light source group and the number of green light sources included in the green light source group can be arbitrary, and they can be consistent or inconsistent. Preferably, the number of blue light sources included in the blue light source group is consistent with the number of green light sources included in the green light source group.

Exemplarily, the handprint collection system 100 may further include a casing, and at least part of the light sources in the one or more image collection devices and the lighting system may be disposed inside the casing. Exemplarily, a window may be provided on the casing, and a light-transmitting plate may be provided on the window. The handprint collecting area can be located above the light-transmitting plate, and the user puts his finger in the hand-print collecting area, and the lighting system below can shine light on the finger through the light-transmitting plate. The image acquisition device below the handprint acquisition area can also acquire fingerprint images of fingers through the light-transmitting plate. Of course, the embodiment in which the handprint collection area is located above the light-transmitting plate is only an example, the light-transmitting plate is optional, and the position of the handprint collection area relative to at least part of the light sources in the image collection device and lighting system can also be changed, as long as The handprint collection area only needs to be located within the imaging range of the image collection device and within the illumination range of the lighting system. In the description herein, the imaging range of any image acquisition device refers to the range covered by a cone with the optical center of the lens of the image acquisition device as the vertex and the viewing angle of the image acquisition device as the cone angle. It should be noted that the light-transmitting plate can be installed in the casing at a set height, so as to avoid the virtual image formed by the illumination source passing through the light-transmitting plate from entering the imaging range of the image acquisition device. It can be understood that the lighting system may also include a light source located near the handprint collection area, that is to say, the lighting system may also include an auxiliary light source located above the light-transmitting plate, so as to illuminate the hand at a position closer to the hand. The auxiliary light source can also include both blue light source and green light source. The auxiliary light source can include one or more of point light sources, line light sources, and surface light sources, and can be located near the hand in the handprint collection area. For example, the auxiliary light source includes light strips composed of point light sources on both sides of the handprint collection area. and a point light near the fingertip location.

The handprint collection area may be a physical space area with any suitable shape, such as a spherical area, a cubic area, or any other regular or irregular area. By way of example and not limitation, the imaging range of one or more image acquisition devices may cover the entire handprint collection area, so as to facilitate the collection of images of the entire handprint collection area. After the user places the finger or palm in the handprint collection area, the image collection device can collect the user's fingerprint or palmprint image. The handprint collection system can be used to collect only one type of hand texture, or it can be used to collect multiple types of hand textures. For example, the handprint collection system can only be used to collect fingerprints in the fingertip area (including fingerprints on the front and side of the finger pad), and can also be used to collect fingerprints in the fingertip area and palm prints at the same time, and can also be used to collect Fingerprints in the fingertip area, lines on the knuckles of the fingers except the knuckles where the fingertips are located, and palm prints on the palm. Multiple types of hand textures can share the same handprint collection area, or use different handprint collection areas, and the handprint collection areas of different types of hand textures can partially or completely overlap.

The number of image capture devices included in the handprint capture system 100 can be set to any appropriate number as required. For example, the number of image acquisition devices may be 1, 2, 3 or 6 and so on.

In one embodiment, the handprint collection system 100 may include a single image collection device. In this case, optionally, the image of the handprint at a single angle can be collected by an image collection device. Of course, optionally, in this case, it is also possible to collect handprint images from multiple angles by rotating and/or moving the image collection device. When the collected handprint is a fingerprint, the implementation scheme of collecting the handprint image at a single angle is more suitable for simulating the fingerprint image obtained by flat printing.

In another embodiment, the handprint collection system 100 may include multiple image collection devices. In this case, optionally, multiple image capture devices may be used to capture handprint images from multiple angles. That is, the optical axes of any two image capture devices among the plurality of image capture devices may form a preset angle with each other, and the preset angle is not equal to 0, so as to collect handprint images at different angles. When the collected handprint is a fingerprint, the angle/height of multiple image acquisition devices can be adjusted so that not only the frontal fingerprint image of the finger pad can be collected, but also the side fingerprint image of the finger pad can be collected, and the handprint image from multiple angles can be collected The implementation scheme of is more suitable for simulating the fingerprint image obtained by rolling stamping. It can be understood that multiple image acquisition devices may be arranged such that their optical axes are approximately perpendicular to the handprint area to be acquired. For example, the optical axis of the image acquisition device used to collect fingerprint images on the front of the finger pad is perpendicular to the front area of the finger pad, and the optical axis of the image acquisition device used to collect fingerprint images on the side of the finger pad is perpendicular to the side area of the finger pad. When the handprint acquisition system is used to acquire multiple types of hand textures, the plurality of image acquisition devices may include an image acquisition device for acquiring a first type of hand texture and an image acquisition device for acquiring a second type of hand texture. The field of view, focal length, placement angle, and position of the image acquisition device for acquiring the first type of hand texture and the image acquisition device for acquiring the second type of hand texture may be different. It can be understood that, compared with the image collection device used for collecting fingerprints, the image collection device for collecting palmprints has a larger field of view. The field of view of an image acquisition device used to collect fingerprints or palmprints may refer to the field of view of a single image acquisition device, or may refer to the field of view of a combination of multiple image acquisition devices. For the same image acquisition device, it can be used to acquire both the first type of hand texture and the second type of hand texture.

It can be understood that the image acquisition device may also include a preview image acquisition device dedicated to preview, and the preview image acquisition device may have a larger field of view than the image acquisition device used for shooting, for example, the field of view of a single preview image acquisition device covers the entire palm The common field of view of multiple image acquisition devices used for shooting covers the entire palmprint. Multiple image acquisition devices can capture multiple palmprint images of target parts such as fingers or palms of the user in one-to-one correspondence, and multiple palmprint images can correspond to different parts of the target site. For example, there are three image acquisition devices, the handprint image collected by the first image acquisition device can mainly correspond to the left part of the finger or palm (i.e. the side area, specifically the side area on the left side), and the handprint image collected by the second image acquisition device The palmprint image captured by the image capture device may mainly correspond to the middle part of the finger or palm (i.e. the frontal area), while the palmprint image captured by the third image capture device may mainly correspond to the right side part of the finger or palm (i.e. side area, specifically the side area on the right side).

The optical axis of the image acquisition device is set towards the side where the handprint of the target part is located, for example, the pad of the finger or the palm of the palm. For example, if it is stipulated that the pads of the fingers of the user face the ground plane when collecting the fingerprints of the user, the optical axis of the image collection device can be set vertically upward or obliquely upward so as to collect the fingerprint of the user's finger.

When there are multiple image capture devices, the heights of the centers of gravity of the multiple image capture devices may be set to be consistent or inconsistent. For example, in the case of collecting palm prints, the heights of the centers of gravity of multiple image capturing devices may be consistent. In the case of collecting handprints, the centers of gravity of multiple image capturing devices may lie on a circular arc.

The processing device 130 is communicatively connected to one or more image acquisition devices, which connection may be wired or wireless. The processing device 130 may receive handprint images collected by one or more image collection devices, and process the handprint images. The processing device 130 can perform any necessary processing operations on the handprint image, including but not limited to one or more of the following: obtaining depth information from the handprint image; performing splicing processing on the handprint images collected by multiple image acquisition devices, etc. wait.

By way of example and not limitation, the processing device 130 may also be communicably connected with the lighting system, and the connection may be wired or wireless. In this case, the processing device 130 may control each light source in the lighting system to emit light according to various lighting schemes described herein. Of course, alternatively, other control devices different from the processing device 130 may also be used to control each light source in the lighting system to emit light. The above-mentioned control device may be a control device in the handprint collection system, or an external control device independent of the handprint collection system.

Different people's skin has different reflection, absorption and transmittance of light, and the same person's hand (finger or palm as an example) has different reflection, absorption and transmittance of light of different wavelengths. In addition, the reflection, absorption and transmission of light are also different when the fingers or palms of the same person are dry, wet or sweaty.

The inventors found that when collecting handprint images, if only green light is used to supplement the light, since the green light is strongly absorbed by the fingers or palms, on the one hand, the light reflected from the fingers or palms to the image acquisition device becomes weaker, which reduces the contrast of the image. On the other hand, the absorption of light by fingers or palms will produce fluorescence and phosphorescence, which will blur the collected images; if only blue light is used to fill the light, due to the weak absorption of blue light by fingers or palms, the fingers or palms will reflect to the image acquisition device The light is strong, and it is easy to overexpose for people with light skin. In addition, if the hands are too dry, there is dead skin or liquid such as sweat, there will be strong reflections, which will easily cause poor contrast. However, both blue light and green light have their own advantages. For example, the contrast of the ridges and valleys of fingerprints or palm prints will be improved under the blue light fill light, which is suitable for people with light fingerprints; while the overdry or wet fingers can be photographed more clearly under the green light fill light.

Therefore, the inventor chooses to supplement the light with blue and green light sources at the same time, so that the two lights can complement each other. As long as a clear image can be collected under one color of light, high-quality images can be obtained relatively easily after processing. Handprint image. Therefore, this scheme of supplementing light with blue and green light sources when collecting handprints can expand the applicability of the handprint collection system to different skin conditions, thereby helping to meet the collection needs of various groups of people.

In order to avoid the mutual influence of blue and green light, the wavelength discrimination of blue and green light sources can be set as large as possible, that is, blue light sources with shorter wavelengths (purple) and green light sources with longer wavelengths (yellow) can be selected as much as possible. By way of example and not limitation, the blue light described herein may be light with a wavelength of less than 430 nm, such as light with a wavelength of 405 nm, and the green light may be light with a wavelength greater than 540 nm, such as light with a wavelength of 560 nm.

In a specific embodiment, the lighting system may include one or more light source sets, each light source set includes at least one blue light source and at least one green light source, one or more light source sets are connected with one or more image acquisition devices one by one correspond.

In this embodiment, the light source set corresponding to any image acquisition device is responsible for supplementing light for the image acquisition device, and each time the image acquisition device captures an image, only the light source set corresponding to it can emit light, and other light source sets do not emit light . Assigning a corresponding supplementary light source to each image acquisition device facilitates the control and management of the image acquisition device and the light source, and facilitates the avoidance of mutual interference of different light sources when acquiring images.

As an example and not limitation, for any light source set in one or more light source sets, the direction of the light emitted by the light source in the light source set may be the same as the handprint collected when the light source in the light source set is turned on. The area is roughly vertical. In this way, the light is approximately perpendicular to the handprint area, which is beneficial to ensure that the valleys and ridges of the handprint can be more accurately presented in the handprint image. When multiple image acquisition devices can be arranged so that their optical axes are roughly perpendicular to the handprint area to be collected, the direction in which the light sources in each light source set emit light is roughly parallel to the direction of the optical axis of the corresponding collection device, which can be achieved by This is achieved by arranging the light sources in the light source set and their corresponding image acquisition devices close enough.

With continued reference to FIG. 1 , optical axes 1122 , 1142 , and 1162 of image capture devices 112 , 114 , and 116 , respectively, are shown. It can be seen from FIG. 1 that the directions in which the light sources in each light source set emit light are parallel to the direction of the optical axis of the corresponding collection device. It should be noted that the parallel described herein does not necessarily require parallel objects to be absolutely parallel to each other, but may be approximately parallel. For example, the parallel may mean that the angle between the parallel object (in this embodiment, the direction of the light emitted by the light source and the direction of the optical axis of the corresponding image acquisition device or any two rays emitted by the same parallel light source) is smaller than the preset angle. Set the threshold. The threshold can be set as small as possible, for example, set to 10° or the like.

According to an embodiment of the present invention, the lighting system includes at least one light source pair, each light source pair includes a blue light source and a green light source, and the distance between the blue light source and the green light source in the same light source pair is smaller than a preset distance threshold.

During image acquisition, the blue light source and the green light source in the same light source pair can be turned on or off at the same time, which is more conducive to ensuring that the imaging conditions of the blue channel and the green channel are closer to the same. The same imaging conditions of the blue channel and the green channel help to improve the fusion effect of the blue channel image and the green channel image in the subsequent image fusion.

However, this embodiment is only an example rather than a limitation to the present invention, and the light sources in the lighting system may all be unpaired, or the lighting system may include light source pairs and unpaired light sources.

Each light source set may include at least one light source pair. Each pair of light sources may include a blue light source and a green light source. The blue light source and the green light source in each light source pair can be as close as possible to further ensure that the imaging conditions of the blue channel and the green channel are close to the same. For example, referring back to FIG. 1, any subset of light sources shown therein (eg, 122, 122', 124, 124', 126, 126') may include at least one pair of light sources such that the blue light source in the subset of light sources It can be conveniently set closer to the green light source.

The preset distance threshold may be set to any appropriate value as required, and the present invention is not limited thereto.

According to an embodiment of the present invention, the illumination system is located outside the imaging range of one or more of the image acquisition devices. In embodiments where the illumination system includes one or more sets of light sources, the set of light sources corresponding to any image capture device may be located outside the imaging range of that image capture device.

The light source can be arranged at any suitable position around the image acquisition device, as long as it does not hinder the imaging of the image acquisition device. The set of light sources corresponding to any image capture device is set outside the imaging range of the image capture device, which can effectively prevent the light source from hindering the image capture device from collecting handprint images.

According to an embodiment of the present invention, one or more image acquisition devices include a first image acquisition device, a second image acquisition device and a third image acquisition device, wherein the optical axis of the first image acquisition device is aligned with the direction of the handprint acquisition area Or the planes of multiple image acquisition devices are vertical, the optical axis of the second image acquisition device forms a first preset angle with the optical axis of the first image acquisition device, the optical axis of the third image acquisition device and the first image acquisition device The optical axis forms a second preset included angle.

The plane of the handprint collection area facing one or more image collection devices may be, for example, a plane parallel to the plane where the above-mentioned shading plate is located. When it is stipulated that the pads of the fingers or the palm of the palm of the user must face the ground plane when the user collects the fingerprints, the plane of the palmprint collection area facing one or more image capture devices can be parallel to the ground plane. At this time, the optical axis of the first image acquisition device may be vertically upward, and the optical axes of the second image acquisition device and the third image acquisition device may be obliquely upward.

Any one of the first preset included angle and the second preset included angle may be set to any appropriate value as required, and the present invention is not limited thereto. The first preset included angle and the second preset included angle may be the same or different. Exemplarily, the first preset included angle may be in the range of 0 to 45 degrees, and the second preset included angle may also be in the range of 0 to 45 degrees.

According to the embodiment of the present invention, the optical axes of the first image acquisition device, the second image acquisition device and the third image acquisition device are located in the same plane.

The arrangement of the optical axes of the three image acquisition devices in the same plane and arranged non-parallel to each other is simple, and also helps to more conveniently acquire images of multiple different parts of target parts such as fingers or palms.

According to the embodiment of the present invention, the handprint collection system may further include: a structured light projector for emitting structured light to the handprint collection area; Handprint images are processed: the grayscale images of the channels corresponding to the structured light are extracted from the handprint images collected by one or more image acquisition devices, and the depth information of the handprints is determined based on the extracted structured light images.

It can be understood that, compared to an illumination light source that is not used for coding but only for illumination, the structured light projector emits structured light for coding.

FIG. 2 shows a schematic diagram of a handprint collection system 100 and related fingers 200 and a handprint collection area 300 according to an embodiment of the present invention. FIG. 2 shows that the handprint collection system 100 further includes a structured light projector 140 . FIG. 1 can be understood as a front view of the handprint collection system 100 , and FIG. 2 can be understood as a left side view of the handprint collection system 100 . It should be noted that FIG. 2 only shows a single image acquisition device 114 as an example for description, and those skilled in the art can understand the positions of other image acquisition devices in FIG. 2 .

The structure of the handprint collection system 100 shown in FIG. 2 is only an example and not a limitation of the present invention, and the handprint collection system 100 according to the embodiment of the present invention is not limited to the situation shown in FIG. 2 . For example, FIG. 2 shows that the structured light projector 140 is located on the side closer to the root of the finger with a specific cross-section 302 as the boundary. The opposite part) is farther horizontally from the root of the finger, wherein the specific cross-section 302 is a cross-section of the cross-section of the finger 200 that overlaps with the central axis of the handprint collection area 300 . The arrangement of the above-mentioned structured light projector 140 is only an example, and it can also be located on the side farther away from the root of the finger bounded by the specific cross-section 302, that is, the head of the structured light projector 140 can also be farther away from the root of the finger than the tail. The horizontal distance is closer. In fact, the structured light projector 140 can be arranged at any suitable position as required, as long as it does not hinder the imaging of the image acquisition device and can illuminate the handprint acquisition area.

By way of example and not limitation, the height of the center of gravity of the structured light projector 140 and the height of the integrated center of gravity or the lowest center of gravity of one or more image acquisition devices may be set to be substantially the same. In this way, it is convenient to arrange the components in the handprint collection system more compactly, and it is beneficial to reduce the volume of the device. By way of example and not limitation, the height of the center of gravity of the structured light projector 140 can be lower than the height of the integrated center of gravity or the lowest center of gravity of one or more image acquisition devices, so that the light projection of the structured light projector 140 can be guaranteed. The area is large enough to cover the acquisition area corresponding to the target site as effectively as possible.

In the case of collecting fingerprints, the target part is relatively small, and the height of the center of gravity of the structured light projector 140 can be set to be substantially the same as the height of the integrated center of gravity or the lowest center of gravity of one or more image acquisition devices. In the case of collecting palm prints, the target site is relatively large, and the height of the center of gravity of the structured light projector 140 may be lower than the height of the combined center of gravity or the lowest center of gravity of one or more image capture devices.

The grayscale image of the channel corresponding to the structured light extracted from any handprint image is the structured light image corresponding to the handprint image. It can be understood that the structured light image includes depth information corresponding to each pixel in the original handprint image. Therefore, through the structured light projector, the depth information of the palm lines of target parts such as fingers or palms can be further obtained. Obtain the depth information of the handprint, which is convenient for subsequent simulation of the handprint image. At present, many occasions may need to be applied to fingerprint images obtained by stamping. Therefore, the scheme of adding structured light can correctly expand the acquired handprint image into a two-dimensional image, so that it can be compared with the fingerprint image obtained by stamping in the subsequent comparison process. Compatible with fingerprint images, expanding the application scenarios of the handprint collection system.

By way of example and not limitation, since two colors of blue and green are used for supplementary light, in order to reduce interference to the blue and green channels, the structured light can try to choose a color that is quite different from blue and green, such as red. Exemplarily, the structured light emitted by the structured light projector may be red light with a wavelength of 660nm. Illumination light and structured light respectively choose blue, green, and red three colors, which is conducive to the subsequent convenient extraction of images of different channels. Of course, red light may not be used for structured light, and image processing can be used to remove the influence of structured light in the blue-green channel.

According to an embodiment of the present invention, the direction of light emitted by the structured light projector forms a third preset angle with the plane where the optical axes of one or more image acquisition devices are located.

The third preset angle can be set to any suitable value as required, and the present invention is not limited thereto. The third preset angle may be different from the above-mentioned first preset angle and the second preset angle, or may be the same as the first preset angle and/or the second preset angle.

It is assumed that the optical axes of all the image acquisition devices in FIG. 2 are in the same plane, and this plane appears as a straight line parallel to the optical axis 1142 in the left view shown in FIG. 2 . It can be seen from FIG. 2 that the direction of light emitted by the structured light projector 140 forms a certain angle with the plane where the optical axis of the image acquisition device is located. This method of arranging the structured light projector on the side of the image acquisition device facilitates the structured light projector to avoid the imaging range of the image acquisition device, so as to avoid hindering the imaging of the image acquisition device. In addition, this method of arranging the structured light projector on the side of the image acquisition device also facilitates the arrangement of the structured light projector at a height similar to that of the image acquisition device, which is conducive to achieving a more compact layout inside the handprint acquisition system.

According to the embodiment of the present invention, the handprint collection system 100 may also include a casing, one or more image collection devices and lighting systems are arranged in the casing, a window is arranged at a position facing the handprint collection area on the casing, and a window is set on the window. There are transparent panels.

The above describes the embodiment in which the image acquisition device and the lighting system are arranged in the casing, and a light-transmitting plate is arranged on the casing, and details will not be repeated here. The light-transmitting plate can be realized by using any suitable material, including but not limited to glass and the like. Exemplarily, the glass may be glass with an anti-reflection coating. The light-transmitting board can play the role of waterproof and dustproof, help protect the main structure of the handprint collection system, and prolong the service life of the equipment.

According to the embodiment of the present invention, the handprint collection system 100 may further include a limiting part, which defines a handprint collection area, and an inlet is provided at the proximal end of the limiting part to allow part or all of the user's hand to pass through the inlet. Enter the handprint collection area; the far end of the limiting component is provided with a stopper, and the stopper is located at a predetermined position in the handprint collection area along the extending direction, so as to limit part or all of the user's hand from extending into the handprint collection area location within.

The proximal end of the limiter can be understood as the end of the limiter that is closer to the front of the user when the user normally uses the handprint collection system, and the far end of the limiter can be understood as the limiter when the user normally uses the handprint collection system on the end that is farther from the front of the user.

Fig. 3 shows a schematic diagram of a part of the handprint collection system according to one embodiment of the present invention. In FIG. 3 , the limiting component 150 is shown, and the inlet 152 and the stop portion 154 of the limiting component 150 are shown. The area between the entrance 152 and the stopper 154 of the limiting component 150 can be set as the handprint collection area 300 . Target parts such as the user's fingers or palms can extend into the palmprint collection area 300 through the entrance 152 . The stopper 154 can limit the limit position that the user's finger or palm can reach, and prevent the user from extending the target part such as finger or palm too far. Through the limit part 150, it is convenient to guide the user to place the target part such as the finger or the palm in the correct position, so as to ensure that the part on the target part that is more suitable for detection (for example, the first knuckle of the finger closest to the fingertip) can Fall into the handprint collection area.

According to the embodiment of the present invention, the handprint collection system 100 may further include a light-shielding component, and the light-shielding component and at least part of the light sources in the lighting system are respectively located on opposite sides of the handprint collection area.

Referring to FIG. 3 , a light shielding member 160 is shown, which is located on opposite sides of the handprint collection area 300 with at least part of the light sources in the lighting system. Wherein, the shading component is located above the handprint collection area, and at least part of the light sources in the lighting system are located below the handprint collection area. The shading component 160 can prevent the light emitted by the light source from reaching the outside to affect the user experience, and at the same time prevent the stray light from the outside from shining into the handprint collection area to interfere with the collection of the handprints.

In the case where the handprint collection system includes a light-shielding component and a light-transmitting plate, the handprint collection area may be at least a part of the area between the light-shielding component and the light-transmitting plate.

Fig. 4 shows a schematic diagram of a partial structure of the handprint collection system 100 and related fingers and handprint collection areas according to an embodiment of the present invention. It should be noted that FIG. 4 is a schematic diagram and does not represent the actual shape or size of each component. Referring to FIG. 4 , it shows the light-shielding member 160 and the light-transmitting plate 170 , and the handprint collection area 300 is disposed therebetween. In addition, FIG. 4 also shows two groups of auxiliary light sources 1281 and 1282 on both sides of the handprint collection area 300 and an auxiliary light source 1283 near the fingertip position of the handprint collection area 300 . In the example shown in Fig. 4, two groups of auxiliary light sources 1281 and 1282 on both sides of the handprint collection area 300 are respectively a light strip, and the auxiliary light source 1283 near the fingertip position of the handprint collection area 300 is a point light source, but this is only is an example, the auxiliary light source may have other implementation forms. In addition, it should be noted that in FIG. 4 , the finger 200 is represented by a dotted line for convenience of distinction.

According to the embodiment of the present invention, in the case that the handprint collection system further includes the above-mentioned limiting part 150, the handprint collection system may also include a shading part 160, and the shading part 160 and the lighting system are respectively located on opposite sides of the handprint collection area. The limiting component 150 also includes a connecting portion connecting the inlet and the stopper, and the upper surface of the connecting portion is attached to the lower surface of the light shielding portion.

Referring to FIG. 3 , the connecting portion 156 connecting the inlet 152 and the stopper portion 154 in the limiting component 150 is shown. The upper surface of the connecting part 156 can be attached to the lower surface of the light shielding part 160, which can better prevent the light emitted by the light source from escaping to the outside and better prevent outside stray light from irradiating the handprint collection area.

According to another aspect of the present invention, a handprint collection method implemented by the above-mentioned handprint collection system 100 is provided. The handprint collection method includes: when the blue light source group emits light with a blue light-emitting scheme, and the green light source group emits light with a green light-emitting scheme, one or more image collection devices are used to collect images of the handprint collection area to obtain one or more The handprint images collected by each image acquisition device, so that in the handprint images collected by each image acquisition device, at least one handprint image is in the case where there is a blue light source with a luminous intensity other than 0 in the blue light source group Collected, at least one handprint image is collected when there is a green light source whose luminous intensity is not 0 in the green light source group; wherein, the blue light source group includes one or more blue light sources, and the green light source group includes one or Multiple green light sources, the blue luminous scheme is used to characterize the luminous intensity of each blue light source, and the green luminous scheme is used to characterize the luminous intensity of each green light source; when collecting, the luminous intensity of at least one light source is not 0.

The structure and arrangement of the lighting system and the image acquisition device can be understood in combination with the above description, and will not be repeated here.

As mentioned above, the lighting system can be divided into two groups according to the colors of the light sources, namely, the blue light source group and the green light source group. The blue light source group may include all blue light sources in the lighting system, and the green light source group may include all green light sources in the lighting system.

For each image acquisition device in the handprint acquisition system, it is only necessary to ensure that at least one of the handprint images collected by it is the case where there is a blue light source with a luminous intensity other than 0 in the blue light source group At least one handprint image is collected when there is a green light source with a luminous intensity not equal to 0 in the green light source group. The time sequence of image collection by all image acquisition devices and the light emission time sequence of all light sources in the lighting system are the same. Can be set as required.

Among the "at least one handprint image" collected when the luminous intensity of the blue light source is not 0 and the "at least one handprint image" collected when the luminous intensity of the green light source is not 0, there may be one or multiple handprint images are the same. For example, for any image acquisition device X, it can acquire two handprint images in total. The first one is when the luminous intensity of at least one blue light source is not 0 and the luminous intensity of all green light sources is 0. The second one is collected when the luminous intensity of at least one green light source is not 0 and the luminous intensity of all blue light sources is 0. For another example, the image acquisition device X may only acquire one handprint image, and the handprint image may be acquired when the luminous intensity of at least one blue light source is not zero and the luminous intensity of at least one green light source is not zero. . For another example, the image acquisition device X can also acquire three handprint images, the first one is acquired when the luminous intensity of at least one blue light source is not 0 and the luminous intensity of all green light sources is 0, the second The second is collected when the luminous intensity of at least one blue light source is not 0 and the luminous intensity of at least one green light source is not 0, and the third is collected when the luminous intensity of at least one green light source is not 0 and all Collected when the luminous intensity of the blue light source is all 0. The above collection schemes of the image collection device X are all feasible, and of course, other numbers of images can be collected and other lighting methods can be used, which will not be repeated here.

For each acquisition of one or more image acquisition devices, the acquisition corresponds to a blue light-emitting scheme and a green light-emitting scheme, and the handprint image obtained in this acquisition is also corresponding to the blue light-emitting scheme. Corresponding to this green lighting scheme. Each blue light emission scheme is used to characterize the luminous intensity of each light source in the blue light source group, and each green light emission scheme is used to characterize the luminous intensity of each light source in the green light source group.

The following takes the blue light source group as an example to illustrate the relationship between light emission and image acquisition of the light source according to the lighting scheme in this paper. The green light source group is similar to the blue light source group, and will not be described in this paper. Assuming that the blue light source group includes three blue light sources B1, B2, and B3, and the luminous intensity of each light source is only divided into two levels, one is when the intensity reaches the maximum, and the other is when the intensity is 0, then theoretically there are (ie There are up to) eight blue glow schemes. Assuming that the maximum luminous intensity of each light source is represented by the number "1", and the intensity of 0 is represented by the number "0", so the above eight blue light-emitting schemes can be expressed as 000, 001, 010, 100, 011, 101, 110 , 111. For the image acquisition device, some or all of the eight blue light-emitting schemes can be used to sequentially emit light, and a corresponding handprint image can be collected under each light-emitting scheme. For example, for the image acquisition device, a total of six blue light-emitting schemes are used to emit light in any order. When the blue light source group emits light according to any blue light-emitting scheme each time, at least part of the images in one or more image acquisition devices The collecting device collects the corresponding handprint image. It should be noted that the same blue light-emitting scheme can appear one or more times. For example, any blue light-emitting scheme P among the above-mentioned six blue light-emitting schemes appears three times, and other blue light-emitting schemes appear once. In the end, eight images, and the emission schemes corresponding to the three images are blue emission scheme P.

It should be noted that, for the image acquisition device, no matter which blue light emitting scheme or green light emitting scheme is used to emit light, the luminous intensity of at least one light source is not 0 during each acquisition.

Although the luminous intensity of each light source is only divided into two levels for description above, it can be understood that the luminous intensity of each light source can have more levels, and the number of luminous intensity levels of any two different light sources They can be the same or different, and these can be set arbitrarily. In the case that the luminous intensity of the blue/green light source has more gears, the maximum possible number of blue/green luminous schemes can also be increased, but the blue/green luminous schemes finally used to supplement light for any image acquisition device can be It can be selected as required, and it can include all possible blue/green light emitting schemes, or only a part of all possible blue/green light emitting schemes.

According to the handprint collection method of the embodiment of the present invention, for each image collection device, at least one of the collected handprint images is collected when the luminous intensity of the blue light source is not 0, and at least one is Collected when the luminous intensity of the green light source is not 0. Therefore, in this method, when each image capture device captures an image, the blue light source and the green light source can be used together to supplement light for the image capture device. This can expand the applicability of the handprint collection method to different skin states, thereby helping to take into account the collection needs of various groups of people.

According to an embodiment of the present invention, the collection includes multiple times, and blue light emission schemes corresponding to at least two of the multiple collections are different, and/or green light emission schemes corresponding to at least two of the multiple collections are different.

For one or more image acquisition devices, the operation of acquiring handprint images can be performed multiple times. The image acquisition devices performing any two different acquisition operations may be the same or different. When controlling the lighting system to emit light, the lighting scheme corresponding to at least two of the above-mentioned multiple collections can be changed. The changed lighting scheme can be a blue lighting scheme, a green lighting scheme, or a blue lighting scheme. Both the scheme and the green glow scheme change. In the case that both the blue light-emitting scheme and the green light-emitting scheme are changed, the at least two acquisitions corresponding to the change of the blue light-emitting scheme and the at least two acquisitions corresponding to the change of the green light-emitting scheme may be completely different or completely the same Or only some of the collections are the same.

The at least two collections with different blue light emitting schemes may be continuous at least two collections, or may be partially or completely discontinuous at least two collections. Similarly, the at least two acquisitions with different green light emission schemes may be at least two acquisitions that are continuous, or at least two acquisitions that are partly or completely discontinuous.

The collection situation faced by the handprint collection system is more complex and will change at any time. For example, different people have different skin conditions, and different people have different positions to place the target parts. Also subject to change. According to different acquisition conditions, the luminescence conditions required to obtain a better-quality handprint image may also be different. If the luminescence scheme is stable during the process of collecting handprint images by the image acquisition device, and only single-quality handprint images can be collected, if the current luminescence scheme is not suitable for the current user's collection situation, it may cause the final obtained handprint image The texture collection effect is not ideal. Therefore, in the process of collecting the handprint image by the image acquisition device, the light-emitting scheme is changed to a certain extent, so that the quality of the collected handprint image can also be changed to a certain extent, which can make up for the limitation of a single handprint image to a certain extent. , which helps to obtain a better handprint collection effect.

According to an embodiment of the present invention, the collection includes multiple times, and the blue light emission schemes corresponding to every two collections in the multiple collections are different, and/or the green light emission schemes corresponding to every two collections in the multiple collections are different.

The above has described the embodiment in which the lighting scheme corresponding to every two acquisitions changes, and the implementation manner of this embodiment can be understood in conjunction with the above description, and details are not repeated here. The luminescence scheme corresponding to every two acquisitions changes, and the luminescence scheme in this way is varied, which helps to better improve the acquisition effect.

According to an embodiment of the present invention, at least two acquisitions correspond to the same blue light emission scheme or green light emission scheme.

In at least two acquisitions, the blue light-emitting scheme may be kept constant and only the green light-emitting scheme may be changed, or the green light-emitting scheme may be kept constant and only the blue light-emitting scheme be changed. Adopting this embodiment, generally speaking, the change span of the lighting scheme is small, and it is convenient to align the handprint images collected at different times based on the constant lighting scheme of the same color.

According to the embodiment of the present invention, there are no two acquisitions corresponding to the same blue light emitting scheme and the same green light emitting scheme.

For the two collections, if the blue light-emitting scheme and the green light-emitting scheme are exactly the same, then two handprint images with basically the same quality will be collected, which is of little significance. For the image acquisition device, all its acquisition operations correspond to different blue light-emitting schemes and/or green light-emitting schemes, so that during the entire acquisition process of the image acquisition device, as many light-emitting schemes as possible can be changed to obtain more Handprint images of different qualities. This helps to increase the probability of a lighting scheme that is more suitable for the current collection situation, and helps to increase the probability of obtaining a high-quality handprint image, thereby helping to improve the final handprint collection effect.

According to an embodiment of the present invention, when the blue light source group emits light in a blue light-emitting scheme, and the green light source group emits light in a green light-emitting scheme, collecting images of the handprint collection area through one or more image acquisition devices includes: at the first moment, When the blue light source group emits light with the first blue light-emitting scheme, and the green light source group emits light with the first green light-emitting scheme, at least part of the image capture devices in the one or more image capture devices are used to collect images of the handprint collection area; At the second moment, when the blue light source group emits light with the second blue light-emitting scheme, and the green light source group emits light with the second green light-emitting scheme, the handprint collection area is collected by at least part of the image collection devices in one or more image collection devices , wherein the first blue light-emitting scheme and the second blue light-emitting scheme are selected from the set of blue light-emitting schemes, the first green light-emitting scheme and the second green light-emitting scheme are selected from the set of green light-emitting schemes; in the set of blue light-emitting schemes Including w kinds of blue lighting schemes, where the maximum value of w is 2 ^k1 , in the 2 ^k1 blue lighting schemes, the luminous intensity of any blue light source is divided into two levels of 0 and non-zero; the set of green lighting schemes includes p kinds of green lighting schemes, where the maximum value of p is 2 ^k2 , in the 2 ^k2 kinds of green lighting schemes, the luminous intensity of any green light source is divided into two levels of 0 and non-0; k1 is the blue light source in the lighting system The total number, k2 is the total number of green light sources in the lighting system; w is an integer greater than or equal to 2 and/or p is an integer greater than or equal to 2; the first blue light-emitting scheme is different from the second blue light-emitting scheme, And/or, the first green lighting scheme is different from the second green lighting scheme.

In this embodiment, the luminous intensity of each light source in the lighting system is only divided into two levels, one is that the luminous intensity is not zero, and the other is that the luminous intensity is zero. Therefore, the set of blue light emitting schemes may include at most 2 ^k1 blue light emitting schemes. Similarly, the set of green lighting schemes can include at most 2 ^k2 -1 green lighting schemes.

For any light source, when it is in a gear whose luminous intensity is not 0, the value of its luminous intensity can be any value, such as the maximum luminous intensity of the light source, or half of the maximum luminous intensity of the light source, and so on.

As mentioned above, during the process of image acquisition by the image acquisition device, the lighting scheme may change. In this embodiment, the first moment and the second moment may emit light according to different blue light emitting schemes and/or different green light emitting schemes respectively. The image acquisition devices that acquire the handprint images at the first moment and the second moment may be completely the same, completely different or partially the same.

This embodiment can be understood in combination with the above description about the change of the lighting scheme, and details are not repeated here.

According to an embodiment of the present invention, the first blue light emitting scheme is the same as the second blue light emitting scheme, or the first green light emitting scheme is the same as the second green light emitting scheme.

Assume below that the blue light source group includes three blue light sources B1, B2, and B3, and the green light source group includes three green light sources G1, G2, and G3, and assume that the luminous intensity of each light source is not 0 and represented by the number "1", An intensity of 0 is represented by the number "0". At the first moment, the first blue light-emitting scheme adopted may be 100, and the first green light-emitting scheme may be 111; and at the second moment, the second blue light-emitting scheme adopted may still be 100, and the second green light-emitting scheme may be 100. Can be changed to 011. In this embodiment, if the blue light-emitting scheme changes, the green light-emitting scheme remains unchanged; otherwise, if the green light-emitting scheme changes, the blue light-emitting scheme remains unchanged.

The advantages of the embodiment in which the blue light emitting scheme and/or the green light emitting scheme are unchanged in at least two acquisitions have been described above, and will not be repeated here.

According to an embodiment of the present invention, when the blue light source group emits light in a blue light-emitting scheme, and the green light source group emits light in a green light-emitting scheme, collecting images of the handprint collection area by one or more image acquisition devices further includes: at the third moment , when the blue light source group emits light with the third blue light-emitting scheme, and the green light source group emits light with the third green light-emitting scheme, at least part of the image capture devices in the one or more image capture devices are used to capture images of the handprint collection area, Wherein, the third blue light-emitting scheme is selected from the set of blue light-emitting schemes, and the third green light-emitting scheme is selected from the set of green light-emitting schemes; the third blue light-emitting scheme is at least the same as the first blue light-emitting scheme and the second blue light-emitting scheme One of them is different; and/or, the third green light-emitting scheme is different from at least one of the first green light-emitting scheme and the second green light-emitting scheme; there are no two acquisitions corresponding to the same blue light-emitting scheme and the same green light-emitting scheme.

The image acquisition device for acquiring the handprint image at the third moment may be completely the same, completely different or partially the same as the image acquisition device for acquiring the handprint image at the first moment. Similarly, the image acquisition device for acquiring the handprint image at the third moment may be completely the same, completely different or partly the same as the image acquisition device for acquiring the handprint image at the second moment.

In this embodiment, a third acquisition is added. In the third acquisition, the blue light emission scheme or the green light emission scheme may be changed relative to at least one of the first two acquisitions.

According to an embodiment of the present invention, the lighting scheme satisfies both the first condition and the second condition; the first condition includes: the first blue lighting scheme is the same as the second blue lighting scheme, or the first green lighting scheme is the same as the second green lighting scheme The scheme is the same; the second condition includes: the third blue light-emitting scheme is the same as the first blue light-emitting scheme, or the third blue light-emitting scheme is the same as the second blue light-emitting scheme, or the third green light-emitting scheme is the same as the first blue light-emitting scheme The green light emitting scheme is the same, or the third green light emitting scheme is the same as the second green light emitting scheme.

In the case that the first blue light-emitting scheme is the same as the second blue light-emitting scheme, the third blue light-emitting scheme is different from the first blue light-emitting scheme and the second blue light-emitting scheme, and the first green light-emitting scheme is different from the second green light-emitting scheme. The lighting schemes are different, and the third green lighting scheme is the same as the first green lighting scheme or the second green lighting scheme. Conversely, when the first green light-emitting scheme is the same as the second green light-emitting scheme, the third green light-emitting scheme is different from the first green light-emitting scheme and the second green light-emitting scheme, and the first blue light-emitting scheme is different from the second blue light-emitting scheme. The schemes are different, and the third blue light-emitting scheme is the same as the first blue light-emitting scheme or the second blue light-emitting scheme.

That is, in three acquisitions, the blue emission scheme is changed once, and the green emission scheme is changed once. In this way, it is convenient to collect handprint images under richer luminous conditions.

According to an embodiment of the present invention, the number of image acquisition devices in one or more image acquisition devices is greater than 1, and all image acquisition devices are used for each acquisition.

All image acquisition devices are used to collect handprint images together during each collection, so that all collections can be completed only by sequentially emitting light according to all required lighting schemes. This collection scheme is more efficient.

According to an embodiment of the present invention, the number of image acquisition devices in the one or more image acquisition devices is greater than 1, and the image acquisition devices used for at least two acquisitions in the multiple acquisitions are not exactly the same.

For example, referring to FIG. 1 , it is assumed that the image acquisition device at the center belongs to the first group of image acquisition devices, and the two image acquisition devices at the two sides belong to the second group of image acquisition devices. Images may be collected by the first group of image acquisition devices at the first moment, and images may be collected by the second group of image acquisition devices at the second moment. Although different image acquisition devices are used to collect images at different times, the handprint images collected by different image acquisition devices can still be spliced. This separate acquisition solution is convenient to avoid that the light sources corresponding to other image acquisition devices hinder the acquisition of the current image acquisition device.

According to an embodiment of the present invention, one or more image acquisition devices include a first image acquisition device, a second image acquisition device and a third image acquisition device, wherein the optical axis of the first image acquisition device is aligned with the direction of the handprint acquisition area Or the planes of multiple image acquisition devices are vertical, the optical axis of the second image acquisition device forms a first preset angle with the optical axis of the first image acquisition device, the optical axis of the third image acquisition device and the first image acquisition device The optical axis forms a second preset angle; the lighting system includes one or more sets of light sources, each set of light sources includes at least one blue light source and at least one green light source, one or more sets of light sources and one or more image acquisition devices One-to-one correspondence; when the blue light source group emits light with a blue light-emitting scheme, and the green light source group emits light with a green light-emitting scheme, the images of the handprint collection area collected by one or more image acquisition devices include: at the first moment, in the blue When the color light source group emits light with the first blue light-emitting scheme, and the green light source group emits light with the first green light-emitting scheme, the image of the handprint collection area is collected by the first group of image acquisition devices; When the second blue light-emitting scheme is used to emit light, and the green light source group emits light with the second green light-emitting scheme, the image of the handprint collection area is collected by the second group of image acquisition devices, wherein the first group of image acquisition devices is the first image One of the acquisition device and the angle image acquisition device, the second group of image acquisition devices is the other in the first image acquisition device and the angle image acquisition device; the angle image acquisition device includes the second image acquisition device and the third image acquisition device , the first blue light-emitting scheme is to make only the luminous intensity of the blue light source in the blue light source group corresponding to the image acquisition device that collects at the first moment is not 0; the first green light-emitting scheme is to make only the green light source group and the second The luminous intensity of the green light source corresponding to the image acquisition device that collects at one moment is not 0; the second blue light emission scheme is to only make the luminous intensity of the blue light source corresponding to the image acquisition device that collects at the second moment in the blue light source group not equal to 0. is 0; the second green light-emitting solution is to only make the luminous intensity of the green light source in the green light source group corresponding to the image acquisition device that collects at the second moment not be 0.

The arrangements of the first image capture device, the second image capture device and the third image capture device have been described above, and will not be repeated here. In addition, the above also describes the embodiment in which the lighting system includes a light source set and the light source set corresponds to the image acquisition device one by one, so details will not be repeated here.

As mentioned above, the first image acquisition device, the second image acquisition device and the third image acquisition device can be divided into two groups, the image acquisition device located in the center is one group, and the two image acquisition devices located on both sides are another group . When any group of image acquisition devices acquires images, only the luminous intensity of the light sources in the corresponding light source set may not be 0, and the luminous intensities of the light sources in other light source sets are all 0.

Since the light source set in the center is relatively close to the light source sets on the left and right sides, it is easier to interfere with the image acquisition of the respective corresponding image acquisition devices. Emits asynchronously, that is, do not emit light at the same time. This helps to obtain a higher-precision handprint image.

In addition, the light source sets on both sides are relatively far away from each other, so the light source sets on both sides can optionally be made to emit light synchronously, which can shorten the time for handprint collection as much as possible. Of course, optionally, it is also feasible to further enable the sets of light sources located on both sides to emit light asynchronously. In this way, the interference of adjacent light sources on the image acquisition device can be avoided as far as possible.

The above scheme of making the first group of light source sets and the second group of light source sets emit light asynchronously can be applied when the light source corresponding to the first group of image acquisition devices affects the image acquisition of the second group of image acquisition devices and/or the second group of images In the case where the light source corresponding to the acquisition device affects the image acquisition of the first group of image acquisition devices.

For example and not limitation, the time difference between the first moment and the second moment may be smaller than a preset time threshold. The preset time threshold can be set to any suitable value as required, and the present invention is not limited thereto. For example, the preset time threshold may be 25ms.

Considering the shaking of fingers or palms, in order to reduce the difficulty of splicing the images of different image acquisition devices together, the time interval between the two sets of light sources that emit light asynchronously should be set as short as possible. It is advisable to exceed 25ms. This asynchronous lighting method is especially suitable for packaged LED modules.

According to an embodiment of the present invention, at the first moment, when the blue light source group emits light in the first blue light emitting scheme and the green light source group emits light in the first green light emitting scheme, the handprint collection area is collected by the first group of image acquisition devices image, including: sending a trigger signal to the first group of image acquisition devices through the processing device at the first moment and sending a light emission control signal to the first group of light source sets corresponding to the first group of image acquisition devices; at the second moment , when the blue light source group emits light with the second blue light-emitting scheme, and the green light source group emits light with the second green light-emitting scheme, the image of the handprint collection area is collected by the second group of image acquisition devices, including: through the processing device at the second 2. Send a trigger signal to the second group of image acquisition devices at any time and send a light emission control signal to the second group of light source sets corresponding to the second group of image acquisition devices; wherein, the trigger signal is used to trigger the corresponding image acquisition device to start acquisition For images, the lighting control signal is used to control the corresponding set of light sources to start to emit light with a non-zero intensity, and the time difference between the first moment and the second moment is equal to the sum of the acquisition time of the first group of image acquisition devices and the preset delay time.

As an example and not a limitation, the image acquisition of each image acquisition device and the light emission of each light source can be controlled by the processing device 130 . The processing device 130 can control the image acquisition device and the corresponding light source set to start working synchronously by simultaneously sending a trigger signal and a light emission control signal to the image acquisition device and the corresponding light source set.

In an embodiment where different groups of light source sets emit light asynchronously and different groups of image acquisition devices asynchronously capture images, the processing device 130 may firstly control the first group of image acquisition devices and the first group of light source sets by synchronously sending trigger signals and light emission control signals. Start to work, and then the acquisition is completed after the acquisition time of the first group of image acquisition devices, and then after a delay for a period of time (that is, the preset delay time), you can start to control the second group of images by synchronously sending trigger signals and light control signals The collection device and the second group of light sources start to work. The acquisition time of the image acquisition device is generally relatively short, such as 2ms. The delay time can be set to be small, and the sum of the delay time and the acquisition time of the first group of image acquisition devices is less than the above-mentioned preset time threshold.

According to an embodiment of the present invention, the lighting system includes one or more light source sets, each light source set includes at least one blue light source and at least one green light source, and the one or more light source sets correspond to one or more image acquisition devices, For any light source set in one or more light source sets, the blue light source and the green light source in the light source set emit light synchronously, and the light-emitting periods of the blue light source and the green light source in the light source set are within the effective period of the corresponding image acquisition device. within the exposure period.

The luminous period of the light source refers to the period when the luminous intensity of the light source is not zero. The exposure mode of any image acquisition device in one or more image acquisition devices may adopt global exposure or line exposure. In the case that the current image acquisition device adopts global exposure, the exposure period of all lines in each frame of image captured by the current image acquisition device is uniform, and the uniform exposure period may be called an effective exposure period. The light-emitting period of each light source in the light source set corresponding to the current image acquisition device only needs to be within the effective exposure period. The light-emitting period of the light sources in the light source set corresponding to the current image capture device may be shorter than or equal to the effective exposure period during global exposure.

In the case that the current image acquisition device adopts row exposure, the effective exposure period may be an exposure period shared by all the rows in each frame of image. Line exposure can be further divided into at least two exposure modes, one is line exposure with initial time synchronization, and the other is line exposure without initial time synchronization.

Fig. 5 shows a schematic diagram of image acquisition and light emitting timing of a light source according to an embodiment of the present invention. The row exposure mode shown in FIG. 5 is synchronized with the initial time, that is, the initial time of the exposure of each row is the same, but the end time is different. For example, the total exposure time is 15 seconds, the exposure time of the first line is 1-10 seconds, the exposure time of the second line is 1-11 seconds, the exposure time of the third line is 1-12 seconds... Exposure times for the six rows are 1-15 seconds. The effective exposure time at this time is 1-10 seconds, so the lighting period of the light source can be set within 1-10 seconds. The total duration during which the luminous intensity of the light source is not 0 may be equal to or shorter than 10 seconds.

For row exposure without initial time synchronization, only the initial time is different from the example shown in FIG. 5 , and other times, such as the end time of each row exposure and data output time, are similar. For example, if there is no initial time synchronization and the total exposure time is 15 seconds, the exposure time of the first row can be 1-10 seconds, the exposure time of the second row is 2-11 seconds, and the exposure time of the third row The times are seconds 3-12...the exposure times for row 6 are seconds 6-15. The effective exposure time at this time is 6-10 seconds, so the lighting period of the light source can be set within 6-10 seconds. The total duration during which the luminous intensity of the light source is not 0 may be equal to or shorter than 5 seconds.

The light-emitting period of the blue light source and the green light source in the light source set is within the effective exposure period of the corresponding image acquisition device, so that different positions (for example, different rows) on the image collected by the image acquisition device are under the same lighting conditions Acquisition is obtained, so as to ensure the consistency of the imaging conditions of the acquired images, which helps to improve the effect of subsequent fusion stitching or splicing fusion.

According to an embodiment of the present invention, the lighting system includes one or more light source sets, each light source set includes at least one blue light source and at least one green light source, and the one or more light source sets correspond to one or more image acquisition devices, Methods also include:

For each of the one or more image capture devices,

Extracting the blue channel and the green channel from the same handprint image collected by the image acquisition device to obtain the current blue channel image and the current green channel image;

Calculating the respective contrast and/or brightness of the current blue channel image and the current green channel image;

Based on the contrast and/or brightness of the current blue channel image and the contrast and/or brightness of the current green channel image, determine the adjusted blue luminous intensity and the adjusted green luminous intensity of the light source set corresponding to the image acquisition device, and adjust the blue luminous intensity. and adjusting the luminous intensity of the green light so that the contrast and/or brightness of the subsequent blue channel image collected by the image acquisition device under the adjusted luminous intensity of the blue light and the subsequent green channel image collected under the adjusted luminous intensity of the green light are consistent;

Controlling the blue light source in the light source set corresponding to the image acquisition device to emit blue light to the handprint collection area according to the adjusted blue light luminous intensity;

The green light source in the light source set corresponding to the image acquisition device is controlled to emit green light to the handprint collection area according to the adjusted green light emission intensity.

The present embodiment will be described below by taking three image acquisition devices and three light source sets as examples. For example, the images of the blue channel and the green channel in the images currently captured by the three image acquisition devices can be extracted in real time, and the contrast and/or the corresponding blue channel images and green channel images of the three image acquisition devices can be calculated. or brightness. For example, the respective brightness values can be obtained by calculating the histogram of the blue channel image and the histogram of the green channel image. Subsequently, the adjusted blue light luminous intensity corresponding to each of the three light source sets corresponding to the three image acquisition devices may be calculated according to the contrast and/or brightness of the three blue channel images corresponding to the three image acquisition devices. In addition, the adjusted green luminous intensity corresponding to each of the three light source sets corresponding to the three image acquisition devices can be calculated according to the contrast and/or brightness of the three green channel images corresponding to the three image acquisition devices. Subsequently, when emitting light next time, each of the three light source sets is controlled to emit light according to the adjusted blue light emission intensity and the adjusted green light emission intensity calculated above and corresponding to itself.

The above embodiments can independently adjust the light source intensity of a single channel. By adjusting the blue and green light sources separately, the light sources of the same color at different collection positions can have relatively consistent contrast and/or brightness, which facilitates the subsequent stitching of images at different collection positions to obtain a better stitching effect. In addition, by independently adjusting the light source intensity of a single channel, the luminous intensity of the current blue-green light source can be adjusted based on the skin's response to light to better adapt to different skin conditions, thereby further adapting to more people.

Those skilled in the art can appreciate that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present invention.

In the several embodiments provided in this application, it should be understood that the disclosed devices and methods may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or May be integrated into another device, or some features may be omitted, or not implemented.

Similarly, it should be understood that in the description of the exemplary embodiments of the invention, in order to streamline the disclosure and to facilitate an understanding of one or more of the various inventive aspects, various features of the invention are sometimes grouped together in a single embodiment, figure , or in its description. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the corresponding claims reflect, the inventive point lies in that the corresponding technical problem may be solved by using less than all features of a single disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this invention.

It will be appreciated by those skilled in the art that all features disclosed in this specification (including accompanying claims, abstract and drawings) and all features of any method or apparatus so disclosed may be used in any combination, except where the features are mutually exclusive. Processes or units are combined. Each feature disclosed in this specification (including accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

The various component embodiments of the present invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art should understand that a microprocessor or a digital signal processor (DSP) may be used in practice to implement some or all functions of some modules in the handprint collection system according to the embodiment of the present invention. The present invention can also be implemented as an apparatus program (for example, a computer program and a computer program product) for performing a part or all of the methods described herein. Such a program for realizing the present invention may be stored on a computer-readable medium, or may be in the form of one or more signals. Such a signal may be downloaded from an Internet site, or provided on a carrier signal, or provided in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means can be embodied by one and the same item of hardware. The use of the words first, second, and third, etc. does not indicate any order. These words can be interpreted as names.

In describing the present invention, it is to be understood that the terms "upper", "lower", "left", "right", "top", "bottom", "inner", "outer" etc. indicate an orientation or position The relationship is based on the orientation or positional relationship in normal use, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. The term "connected" may mean directly connected or indirectly connected via other devices or elements.

The above is only a specific embodiment of the present invention or a description of the specific embodiment, and the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily Any changes or substitutions that come to mind should be covered within the protection scope of the present invention. The protection scope of the present invention should be based on the protection scope of the claims.

Claims (23)

1. A hand print acquisition system comprising:

a lighting system comprising one or more blue light sources and one or more green light sources, each light source for emitting light towards a palm print acquisition zone for placing part or all of a user's hand;

one or more image acquisition devices for acquiring images of the palm print acquisition area while the illumination system is emitting light to the palm print acquisition area to obtain palm print images;

and the processing device is used for processing the hand vein images acquired by the one or more image acquisition devices.

2. The system of claim 1, wherein the blue light source emits blue light having a wavelength less than 430nm and the green light source emits green light having a wavelength greater than 540nm.

3. The system of claim 1 or 2, wherein the palm print acquisition system further comprises:

a structured light projector for emitting structured light toward the palm print collection zone;

the processing device processes the hand vein image acquired by the one or more image acquisition devices in the following way:

And respectively extracting gray images of channels corresponding to the structured light from the hand vein images acquired by the one or more image acquisition devices, and determining hand vein depth information based on the extracted structured light images.

4. The system of any of claims 1-3, wherein the one or more image acquisition devices comprise a first image acquisition device, a second image acquisition device, and a third image acquisition device, wherein,

the optical axis of the first image acquisition device is perpendicular to the plane of the palm print acquisition area facing the one or more image acquisition devices, the optical axis of the second image acquisition device and the optical axis of the first image acquisition device form a first preset included angle, and the optical axis of the third image acquisition device and the optical axis of the first image acquisition device form a second preset included angle.

5. The system of claim 4, wherein the optical axes of the first, second, and third image acquisition devices lie in the same plane.

6. The system of any of claims 1-5, wherein the palm print acquisition system further comprises a shade member, the shade member and at least a portion of the light sources in the illumination system being positioned on opposite sides of the palm print acquisition zone, respectively.

7. The system of any one of claims 1 to 6, wherein the fingerprint acquisition system further comprises a spacing member defining the fingerprint acquisition area,

an inlet is arranged at the proximal end of the limiting component so as to allow part or all of the hand of the user to extend into the palm print collecting area through the inlet;

the distal end of the limiting member is provided with a stopper portion located at a predetermined position of the palm print collecting area along the extending direction so as to limit a portion or all of the user's hand from extending into the position within the palm print collecting area.

8. The system of claim 7, wherein,

the limiting part further comprises a connecting part for connecting the inlet with the stop part, and the upper surface of the connecting part is attached to the lower surface of the shading part.

9. The system of any of claims 1-8, wherein the illumination system comprises one or more light source sets, each light source set comprising at least one blue light source and at least one green light source, the one or more light source sets being in one-to-one correspondence with the one or more image capture devices.

10. The system of claims 1-9, wherein the illumination system comprises at least one light source pair, each light source pair comprising one blue light source and one green light source, the distance between the blue light source and the green light source within the same light source pair being less than a preset distance threshold.

11. A method of fingerprint acquisition implemented with the fingerprint acquisition system of any one of claims 1 to 10, comprising:

acquiring images of the hand print acquisition area by the one or more image acquisition devices when the blue light source group emits light in a blue light emission scheme and the green light source group emits light in a green light emission scheme, so as to acquire hand print images acquired by the one or more image acquisition devices, wherein at least one hand print image is acquired under the condition that a blue light source with luminous intensity which is not 0 exists in the blue light source group, and at least one hand print image is acquired under the condition that a green light source with luminous intensity which is not 0 exists in the green light source group;

the blue light source group comprises one or more blue light sources, the green light source group comprises one or more green light sources, a blue light emitting scheme is used for representing the light emitting intensity of each blue light source, and a green light emitting scheme is used for representing the light emitting intensity of each green light source; at the time of collection, the luminous intensity of at least one light source is not 0.

12. The method of claim 11, wherein the acquiring comprises acquiring a plurality of times, at least two of the plurality of acquisitions differing in a corresponding blue light emission scheme, and/or at least two of the plurality of acquisitions differing in a corresponding green light emission scheme.

13. The method of claim 11, wherein the acquiring comprises a plurality of acquisitions, each of the plurality of acquisitions differing in a corresponding blue light emission scheme, and/or each of the plurality of acquisitions differing in a corresponding green light emission scheme.

14. The method of claim 12 or 13, wherein at least two acquisitions of the corresponding blue or green lighting scheme are identical.

15. The method of any of claims 12-14, wherein there are no two acquisitions corresponding to the same blue light emission scheme and the same green light emission scheme.

16. The method of claim 11, wherein the capturing, by the one or more image capturing devices, the image of the palm print capture area while the blue light source set emits light in a blue light emission scheme and the green light source set emits light in a green light emission scheme comprises:

at a first moment, when the blue light source group emits light according to a first blue light emitting scheme and the green light source group emits light according to a first green light emitting scheme, acquiring images of the palm print acquisition area through at least part of the image acquisition devices in the one or more image acquisition devices;

at a second moment, when the blue light source group emits light according to a second blue light emitting scheme and the green light source group emits light according to a second green light emitting scheme, the image of the palm print collecting area is collected by at least part of the image collecting devices in the one or more image collecting devices,

Wherein the first blue light emitting scheme and the second blue light emitting scheme are selected from a set of blue light emitting schemes, and the first green light emitting scheme and the second green light emitting scheme are selected from a set of green light emitting schemes; the blue light emitting scheme set comprises w blue light emitting schemesW has a maximum value of 2 ^k1 At 2 ^k1 In the blue light emitting scheme, the light emitting intensity of any blue light source is divided into 0 and non-0 steps; the green light emitting scheme set comprises p green light emitting schemes, wherein the maximum value of p is 2 ^k2 At 2 ^k2 In the green light emitting scheme, the light emitting intensity of any green light source is divided into 0 and non-0 steps; k1 is the total number of blue light sources in the lighting system and k2 is the total number of green light sources in the lighting system; w is an integer greater than or equal to 2 and/or p is an integer greater than or equal to 2; the first blue light emitting scheme is different from the second blue light emitting scheme, and/or the first green light emitting scheme is different from the second green light emitting scheme.

17. The method of claim 16, wherein the first blue light emitting scheme is the same as the second blue light emitting scheme or the first green light emitting scheme is the same as the second green light emitting scheme.

18. The method of claim 16 or 17, wherein the capturing, by the one or more image capturing devices, the image of the palm print capture area while the blue light source set emits light in a blue light emission scheme and the green light source set emits light in a green light emission scheme further comprises:

at a third moment, when the blue light source group emits light according to a third blue light emitting scheme and the green light source group emits light according to a third green light emitting scheme, the image of the palm print collecting area is collected by at least part of the image collecting devices in the one or more image collecting devices,

wherein the third blue light emitting scheme is selected from the set of blue light emitting schemes and the third green light emitting scheme is selected from the set of green light emitting schemes;

the third blue light emitting scheme is different from at least one of the first blue light emitting scheme and the second blue light emitting scheme; and/or, the third green light emitting scheme is different from at least one of the first green light emitting scheme and the second green light emitting scheme;

there are no two acquisitions corresponding to the same blue light emission scheme and the same green light emission scheme.

19. The method of claim 18, wherein the lighting scheme satisfies both the first condition and the second condition;

The first condition includes: the first blue light emitting scheme is the same as the second blue light emitting scheme, or the first green light emitting scheme is the same as the second green light emitting scheme;

the second condition includes: the third blue light emitting scheme is the same as the first blue light emitting scheme, or the third blue light emitting scheme is the same as the second blue light emitting scheme, or the third green light emitting scheme is the same as the first green light emitting scheme, or the third green light emitting scheme is the same as the second green light emitting scheme.

20. The method of any of claims 11-19, wherein a number of image acquisition devices of the one or more image acquisition devices is greater than 1, using all image acquisition devices per acquisition.

21. The method of any of claims 11-19, wherein a number of image capture devices in the one or more image capture devices is greater than 1, the image capture devices used for at least two of the multiple acquisitions not being identical.

22. The method of claim 21, wherein the one or more image capture devices comprise a first image capture device, a second image capture device, and a third image capture device, wherein,

The optical axis of the first image acquisition device is perpendicular to the plane of the palm print acquisition area facing the one or more image acquisition devices, the optical axis of the second image acquisition device forms a first preset included angle with the optical axis of the first image acquisition device, and the optical axis of the third image acquisition device forms a second preset included angle with the optical axis of the first image acquisition device; the illumination system comprises one or more light source sets, each light source set comprises at least one blue light source and at least one green light source, and the one or more light source sets are in one-to-one correspondence with the one or more image acquisition devices;

when the blue light source group emits light according to a blue light emitting scheme and the green light source group emits light according to a green light emitting scheme, the capturing the image of the palm print capturing area by the one or more image capturing devices includes:

at a first moment, when the blue light source group emits light according to a first blue light emitting scheme and the green light source group emits light according to a first green light emitting scheme, acquiring an image of the palm print acquisition area through the first group of image acquisition devices;

at a second moment, when the blue light source group emits light according to a second blue light emitting scheme and the green light source group emits light according to a second green light emitting scheme, the second group of image acquisition devices acquire the image of the palm print acquisition area,

Wherein the first group of image acquisition devices are one of the first image acquisition devices and the angle image acquisition devices, and the second group of image acquisition devices are the other one of the first image acquisition devices and the angle image acquisition devices; the angle image acquisition device comprises the second image acquisition device and the third image acquisition device, and the first blue light emission scheme is that the blue light source corresponding to the image acquisition device for acquisition at the first moment in the blue light source group is not 0 in light emission intensity; the first green light emitting scheme is that the light emitting intensity of the green light sources corresponding to the image acquisition device for acquiring at the first moment in the green light source group is not 0; the second blue light emitting scheme is that the light emitting intensity of the blue light source corresponding to the image acquisition device for acquiring at the second moment in the blue light source group is not 0; the second green light emitting scheme is that only the green light source light emitting intensity corresponding to the image acquisition device for acquiring at the second moment in the green light source group is not 0.

23. The method of any of claims 11 to 22, wherein the illumination system comprises one or more light source sets, each light source set comprising at least one blue light source and at least one green light source, the one or more light source sets being in one-to-one correspondence with the one or more image acquisition devices, the method further comprising:

For each of the one or more image acquisition devices,

extracting a blue channel and a green channel from the same palm print image acquired by the image acquisition device to obtain a current blue channel image and a current green channel image;

respectively calculating the contrast and/or brightness of each of the current blue channel image and the current green channel image;

determining the adjusted blue light luminous intensity and the adjusted green light luminous intensity of a light source set corresponding to the image acquisition device based on the contrast and/or brightness of the current blue channel image and the contrast and/or brightness of the current green channel image, wherein the adjusted blue light luminous intensity and the adjusted green light luminous intensity enable the contrast and/or brightness of a subsequent blue channel image acquired by the image acquisition device under the adjusted blue light luminous intensity and the contrast and/or brightness of a subsequent green channel image acquired by the image acquisition device under the adjusted green light luminous intensity to be consistent;

blue light sources in a light source set corresponding to the image acquisition device are controlled to emit blue light to the palm print acquisition area according to the adjusted blue light luminous intensity;

and controlling green light sources in the light source set corresponding to the image acquisition device to emit green light to the palm print acquisition area according to the adjusted green light luminous intensity.