CN112232304B - Non-contact type finger/palm print acquisition device and method - Google Patents

Abstract

The present invention discloses a non-contact finger and palm print collection device and method, comprising: a first shooting mechanism, a second shooting mechanism, and a shell; the first shooting mechanism and the second shooting mechanism are installed on a supporting structure in the shell, and a finger placement area and a palm placement area are provided on the outside of the shell; the first shooting mechanism comprises a rotating device, a linear array camera installed on the rotating device, and a first lighting light column with a preset angle; the second shooting mechanism comprises a moving device, an area array camera installed on the moving device, and a second lighting light column with a preset angle. The linear array camera is rotated around the fingerprint surface to scan and shoot the fingerprint in all directions, and a high-quality and large-area 2D fingerprint image of the fingerprint surface of the finger is directly obtained; the main palm print and the side palm print are photographed by a movable area array camera, and the main palm print and the side palm print images are obtained by one-time shooting without moving the palm; the two shooting mechanisms are integrated into one through the shell, thereby improving the comprehensive collection performance of the finger and palm prints.

Description

A non-contact finger and palm print collection device and method

Technical Field

The invention belongs to the field of finger and palm print collection, and relates to a non-contact finger and palm print collection device and method.

Background Art

Most traditional fingerprint and palm print image acquisition systems used in public security systems, security, customs, and entry and exit rely on physical contact between fingers and palms and fingerprint and palm print acquisition devices. When high-quality, complete, and large-area fingerprints are required, fingers and palms need to be pressed on the fingerprint and palm print acquisition device and rolled from one side to the other to increase the total contact area. When such equipment is used by unskilled and non-compliant persons, the additional force used for acquisition often causes large deformation and distortion of fingerprints and palm prints, and the person being collected may intentionally or unconsciously move his fingers or palms during the acquisition process, causing the collected fingerprint and palm print images to become blurred, thereby failing to acquire. These problems greatly increase the difficulty and time of acquiring large-area and high-quality fingerprints and palm prints, resulting in poor user experience. Contact fingerprint and palm print acquisition devices not only have slow acquisition speeds, but also cause people to have concerns about hygiene.

Some non-contact fingerprint and palm print collection methods, such as using multiple array cameras or 3D depth cameras (such as binocular cameras or trinocular stereo cameras) combined with structured light to shoot, require a lot of post-processing and adjustment by software (such as 3D modeling and then expanding it into 2D images or image stitching methods, etc.), and the generated images will also have stitching marks and there will be a large difference between the image and the real object. The quality of the palm print images collected by these non-contact fingerprint and palm print collectors is not good enough, the fingerprint area collected is limited, and there are reliability issues.

Summary of the invention

The purpose of the present invention is to provide a non-contact finger and palm print collection device and method for photographing fingerprints around a fingerprint surface with a linear array camera and photographing main palm prints and side palm prints with an area array camera. For fingerprints, the fingerprint can be scanned and photographed in all directions by rotating around the fingerprint surface, and a 2D fingerprint image of the finger fingerprint surface can be directly obtained, so as to obtain a higher image quality and a fingerprint image of a larger area. For palm prints, the main palm print and side palm print images can be obtained by photographing at one time without moving the palm. The device is a comprehensive collection device integrating fingerprints, main palm prints and side palm prints, and greatly improves the comprehensive collection performance of finger and palm prints.

The technical solution of the present invention is:

In a first aspect, a non-contact finger and palm print collection device comprises: a first photographing mechanism, a second photographing mechanism, and a shell; the first photographing mechanism and the second photographing mechanism are installed on a supporting structure in the shell, and a finger placement area and a palm placement area are provided on the outside of the shell, the finger placement area corresponds to a photographing position of the first photographing mechanism, and the palm placement area corresponds to a photographing position of the second photographing mechanism;

The first shooting mechanism includes a rotating device, a linear array camera mounted on the rotating device, and a first lighting light column with a preset angle; the rotating device drives the linear array camera and the first lighting light column to rotate around the finger placement area, and triggers the linear array camera to scan and shoot the fingerprint surface of the finger during the rotation process, and the first lighting light column is aligned with the photographed fingerprint surface of the finger during the rotation process;

The second shooting mechanism includes a moving device, an area array camera installed on the moving device, and a second lighting light column with a preset angle; the moving device drives the area array camera and the second lighting light column to move parallel to the palm placement area and tilt toward the palm placement area at the stop positions on both sides, and triggers the area array camera to shoot the palm print surface of the palm when moving to the center position of the palm and the stop positions on both sides, and the second lighting light column is aimed at the photographed palm print surface.

A further technical solution is: the rotating device comprises a first mounting platform, a first stepper motor, a first synchronous wheel, a first synchronous belt, and a first encoding pulse trigger;

The first synchronous wheel and the first coded pulse trigger are installed on the output shaft of the first stepper motor, and the first synchronous belt connects the first mounting platform and the first synchronous wheel; the first coded pulse trigger sends a first pulse trigger signal according to the rotation of the first stepper motor, so as to trigger the linear array camera to scan and shoot; the first stepper motor drives the first synchronous wheel to rotate, the first synchronous wheel drives the first synchronous belt to transmit, the first synchronous belt drives the first mounting platform to rotate, and the first mounting platform is used to install the linear array camera and the first illumination light column.

A further technical solution is that a predetermined angle is preset between the plane where the lens of the linear array camera is located and the direction of the finger axis, and the side of the linear array camera close to the fingertip is inclined toward the fingertip.

Its further technical solution is: an automatic pop-up positioning mechanism is provided in the finger placement area on the shell, and the automatic pop-up positioning mechanism includes a finger placement bracket that can pop out and automatically reset, and an arc-shaped soft-glue finger clamping device, and the arc-shaped soft-glue finger clamping device is used to clamp the finger on the finger placement bracket, and the finger placement bracket is provided with a movable template corresponding to the fingertip position, and the movable template is automatically pulled out when the finger placement bracket is automatically reset.

Its further technical solution is: annular finger sleeves of different sizes, the annular finger sleeves are used to be put on the finger joints, the outer rings of the annular finger sleeves of different sizes match the automatic pop-up positioning mechanism, the inner rings of the annular finger sleeves of different sizes respectively match the finger sizes of different thicknesses, the position of the annular finger sleeves on the fingers corresponds to the position of the arc-shaped soft-glue finger locking device, and the annular finger sleeves correspond to the position of the shell when the finger placement bracket is reset.

A further technical solution is: the shell also includes a suction cup mounting bracket, a suction cup device is installed on the suction cup mounting bracket, the suction cup device corresponds to the back of the finger, and the suction cup device fixes the back of the finger through the suction force generated by negative pressure.

Its further technical solution is: the mobile device includes a second installation platform, a second stepping motor, a second synchronous wheel, a second synchronous belt, and a second encoding pulse trigger;

The second synchronous wheel and the second encoded pulse trigger are installed on the output shaft of the second stepper motor, and the second synchronous belt connects the second mounting platform and the second synchronous wheel; the second encoded pulse trigger sends a second pulse trigger signal according to the rotation of the second stepper motor, which is used to trigger the area array camera to shoot; the second stepper motor drives the second synchronous wheel to rotate, and the second synchronous wheel drives the second synchronous belt to transmit, and the second synchronous belt drives the second mounting platform to move and stop at the stop positions on both sides, and the second mounting platform is used to install the area array camera and the second illumination light column.

A further technical solution is: the moving device also includes a tilt control device, and the tilt control device is used to control the second mounting platform to tilt to a preset tilt angle.

A further technical solution is: the palm placement area on the shell is a transparent support plane, and the transparent support plane is parallel to the shooting plane of the area array camera on the second mounting platform;

The palm placement area is provided with photosensitive tubes arranged at a predetermined interval, and the photosensitive tubes are used to determine the size and position of the palm according to the number of photosensitive tubes blocked by the palm.

A further technical solution is that the stop positions on both sides of the second mounting platform are determined according to the size and position of the palm and a preset tilt angle of the second mounting platform.

A further technical solution is: a palm limiting device is arranged outside the palm placement area of the shell, and the palm limiting device includes four limiting rods corresponding to the roots of the finger joints, which are used to guide the palm to be placed in a preset position.

A further technical solution is that the non-contact finger and palm print collection device also includes an air bag, and the air bag is used to automatically descend and press on the back of the hand after the palm is placed.

In a second aspect, a non-contact finger and palm print collection method is applied to the non-contact finger and palm print collection device as described in the first aspect, and the method comprises:

Fingerprint data collection part:

The linear array camera and the first illumination beam are driven by the rotating device to rotate around the finger placement area by a predetermined angle from a preset initial position, and scan and shoot at the same time;

Transmitting the fingerprint surface image collected by the linear array camera to the host computer;

The upper computer preprocesses the fingerprint surface image, including noise filtering, sharpness and saturation enhancement; the preprocessed fingerprint image is edge-recognized to extract the main fingerprint area; the regional fingerprint image is normalized to limit the grayscale value, separate the foreground color and background color, enhance the fingerprint texture along the ridge direction, remove the holes and burrs in the fingerprint, and output the 2D fingerprint image after the texture is refined;

Palmprint data collection part:

The area array camera and the second illumination light column are driven by the moving device to move to the center of the palm placement area to capture the main palm print image, and the area array camera and the second illumination light column are driven by the moving device to move to the stop positions on both sides and tilted toward the palm placement area to capture the side palm print images on both sides respectively;

The main palm print image and the side palm print image taken by the area array camera are transmitted to the host computer, and the palm print surface image is obtained by splicing and processing;

The palm print surface image is preprocessed by the host computer, including noise filtering, sharpness and saturation enhancement; the edge recognition is performed on the preprocessed palm print image to extract the main area of the palm print; the regional palm print image is normalized to limit the gray value, separate the foreground color and the background color, enhance the palm print pattern along the ridge direction, remove the holes and burrs in the palm print, and output the 2D palm print image after the texture is refined;

Data storage part;

The output 2D fingerprint image and 2D palm print image are stored in correspondence with the identity information of the person being collected through the host computer.

The advantages of the present invention are:

1. The linear array camera rotates around the fingerprint surface to scan and shoot fingerprints in all directions, avoiding the problem of image stitching hum and large differences in image matching with the actual object caused by the need for a large amount of post-processing and adjustment of the image by multiple area array cameras or 3D depth cameras. The 2D fingerprint image of the fingerprint surface of the finger can be directly obtained, with higher image quality and a larger area of fingerprint image; the main palm print and side palm print can be shot at once without moving the palm by using a movable area array camera to obtain the main palm print and side palm print images; the two shooting mechanisms are integrated into one through the shell to form a comprehensive collection device for fingerprints, main palm prints and side palm prints, which greatly improves the comprehensive collection performance of fingerprints and palm prints;

2. By setting a preset angle between the plane where the lens of the line scan camera is located and the axis direction of the finger, and tilting it toward the fingertip, the lines on the fingertip can be taken into account during the rotation and shooting process of the line scan camera;

3. By setting up ring-shaped finger sleeves of different sizes, since the outer ring of the ring-shaped finger sleeve matches the finger placement bracket, and the inner ring is suitable for fingers of different sizes, different finger sizes can be fixed on the finger placement bracket to prevent the finger from moving during the collection process, thereby ensuring the image quality of fingerprint collection;

4. Fixing the back of the finger by the suction cup device can further keep the finger fixed and ensure the image quality of fingerprint collection;

5. By pressing the back of the hand with the airbag, the palm can be prevented from being suspended in the air during the collection process, thus ensuring the quality of palm print collection.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

FIG1 is a schematic structural diagram of a non-contact finger and palm print collection device provided by the present application;

FIG2 is a schematic diagram of the side structure of a non-contact finger and palm print collection device provided by the present application;

FIG3 is a schematic diagram of a rotating device and a moving device provided by an embodiment of the present application;

FIG4 is a schematic diagram of a rotating device and a moving device provided by another embodiment of the present application;

FIG5 is a schematic diagram of a first photographing mechanism provided by the present application;

FIG6 is a schematic diagram of fingerprint collection provided by the present application;

FIG7 is a schematic diagram of the movement of a linear array camera for fingerprint collection provided by the present application;

FIG8 is a schematic diagram of illumination for fingerprint collection provided by the present application;

FIG9 is a schematic diagram of an automatic pop-up positioning mechanism for fingerprint collection provided by the present application;

FIG10 is a schematic diagram of palm print collection provided by the present application;

FIG11 is a schematic diagram of the movement of an area array camera for palm print collection provided by the present application;

FIG12 is a schematic diagram of illumination for palm print collection provided by the present application;

FIG. 13 is a schematic diagram of palm compression for palm print collection provided in the present application.

Among them: 10, first shooting mechanism; 11, rotating device; 111, first mounting platform; 112, first stepper motor; 12, linear array camera; 13, first lighting beam; 20, second shooting mechanism; 21, moving device; 211, second mounting platform; 212, second stepper motor; 22, area array camera; 23, second lighting beam; 24, airbag; 30, shell; 31, supporting structure; 32, finger placement bracket; 33, arc-shaped soft-glue finger positioning device; 34, movable template; 35, suction cup mounting bracket; 36, transparent supporting plane; 37, palm limiting device.

DETAILED DESCRIPTION

Embodiment: In order to solve the inconvenience of the contact-type finger and palm print collection method, the present application provides a non-contact finger and palm print collection device. With reference to Figures 1 to 13, the non-contact finger and palm print collection device includes: a first shooting mechanism 10, a second shooting mechanism 20, and a shell 30; the first shooting mechanism 10 and the second shooting mechanism 20 are installed on a supporting structure 31 in the shell 30, and the outside of the shell 30 is provided with a finger placement area and a palm placement area, the finger placement area corresponds to the shooting position of the first shooting mechanism 10, and the palm placement area corresponds to the shooting position of the second shooting mechanism 20.

The first shooting mechanism 10 includes a rotating device 11, a linear array camera 12 installed on the rotating device 11, and a first illumination light column 13 with a preset angle; the rotating device 11 drives the linear array camera 12 and the first illumination light column 13 to rotate around the finger placement area, and triggers the linear array camera 12 to scan and shoot the finger fingerprint surface during the rotation process, and the first illumination light column 13 is aligned with the photographed finger fingerprint surface during the rotation process.

The first illumination light column 13 is pre-adjusted at an angle according to the distance between the linear array camera 12 and the finger placement area and the installation position of the first illumination light column 13, so that the first illumination light column 13 rotates synchronously with the linear array camera 12, and the illumination area of the first illumination light column 13 is always aligned with the shooting area of the linear array camera 12. As shown in the figure, multiple first illumination light columns 13 with preset angles are aligned with the same shooting target position of the linear array camera 12 to increase the illumination. The first illumination light column 13 can be installed at a position and quantity according to actual needs.

Optionally, the rotating device 11 includes a first mounting platform 111, a first stepper motor 112, a first synchronous wheel, a first synchronous belt, and a first encoding pulse trigger.

The output shaft of the first stepper motor 112 is installed with the first synchronous wheel and the first coding pulse trigger, and the first synchronous belt connects the first mounting platform 111 and the first synchronous wheel; the first coding pulse trigger sends a first pulse trigger signal according to the rotation of the first stepper motor 112, which is used to trigger the linear array camera 12 to scan and shoot; the first stepper motor 112 drives the first synchronous wheel to rotate, the first synchronous wheel drives the first synchronous belt to drive, the first synchronous belt drives the first mounting platform 111 to rotate, and the first mounting platform 111 is used to install the linear array camera 12 and the first illumination light column 13.

In practical applications, the first stepper motor 112 can be installed at the bottom of the housing 30 to drive the first mounting platform 111 to rotate through the first synchronous wheel and the first synchronous belt, thereby driving the linear array camera 12 and the first illumination light column 13 to rotate as a whole.

In practical applications, the first synchronous belt can be connected to the arc-shaped mechanism on the first mounting platform 111. During the transmission process of the first synchronous belt, the arc-shaped mechanism is driven to move along an arc-shaped route, thereby driving the first mounting platform 111 to rotate. Exemplarily, the first mounting platform 111 is integrally connected with the arc-shaped mechanism through the support structure 31, and is respectively arranged on both sides of the support structure 31, and can be synchronously rotated around the connection position on the support structure 31 under the drive of the first synchronous belt.

The first coding pulse trigger is installed together with the output shaft of the first stepper motor 112. For example, when the output shaft of the first stepper motor 112 rotates one circle, the first coding pulse trigger sends 2500 pulse signals, and each pulse signal triggers the linear array camera 12 to shoot once, so that while the first stepper motor 112 drives the linear array camera 12 to rotate, the linear array camera 12 can achieve continuous shooting, and usually the entire fingerprint surface can be collected within a few seconds. The linear array camera 12 captures a line image once, and the lines captured continuously during the rotation process finally form a surface to obtain the finger fingerprint image. Using the linear array camera 12 to rotate around the fingerprint surface to shoot the fingerprint not only has the advantage of faster speed, generally the continuous action collection speed is less than 3s, but also can scan and shoot the complete fingerprint in all directions, directly obtain the 2D fingerprint image of the fingerprint surface of the finger, obtain higher image quality, obtain a fingerprint image of a larger area, and have good repeatability for multiple collections of the same finger fingerprint, which is better than the fingerprint rolling fingerprint collection method.

The aperture of the line scan camera lens has an F value of 4-12, where the F value is the ratio of the focal length of the line scan camera lens to the diameter of the entrance pupil. A large F number corresponds to a small aperture, which increases the depth of field, thereby adapting to the thickness of different fingers while still capturing a clear image of the fingerprint. However, if the F value is too large, too little light enters the camera, resulting in insufficient lighting. Therefore, an F value in the range of 4-12 is used to balance a large depth of field and good lighting.

The rotation angle of the rotating device 11 is preset and is subdivided and controlled by the first stepper motor, so that the linear array camera 12 rotates smoothly around the fingerprint surface and triggers the shooting synchronously.

It should be noted that, in actual applications, the first shooting mechanism also includes necessary power supply devices and control devices. The power supply device is used to supply power to the operation of each component. The control device can be used to control the rotation of the motor, receive trigger signals, and control the shooting of the line array camera 12. The line array camera 12 can also be connected to the host computer to upload the collected images to the host computer for further image processing.

Optionally, a predetermined angle is preset between the plane where the lens of the line array camera 12 is located and the axis direction of the finger, and the side of the line array camera 12 close to the fingertip is inclined toward the fingertip.

In order to capture the lines on the fingertips, the lens of the linear array camera 12 is slightly tilted toward the fingertips, so that the lines on the finger surface and the lines on the fingertips can be captured at the same time to obtain a larger area of fingerprints. For example, the angle between the plane where the lens of the linear array camera 12 is located and the finger axis direction is about 10°.

Optionally, an automatic pop-up positioning mechanism is provided in the finger placement area on the shell 30, and the automatic pop-up positioning mechanism includes a finger placement bracket 32 that can pop out and automatically reset, and an arc-shaped soft-glue finger clamping device 33. The arc-shaped soft-glue finger clamping device 33 is used to clamp the finger on the finger placement bracket 32. The finger placement bracket 32 is provided with a movable template 34 corresponding to the fingertip position, and the movable template 34 is automatically pulled out when the finger placement bracket 32 is automatically reset.

As shown in the figure, exemplarily, the arc-shaped soft-glue finger locking device 33 is arranged above the finger placement bracket 32. When the finger is placed on the finger placement bracket 32, the arc-shaped soft-glue finger locking device 33 automatically descends to press the finger to fix the position of the finger, ensuring that the finger is in the fingerprint collection area and preventing the finger from moving during the fingerprint collection process.

The movable template 34 provided on the finger placement bracket 32 can be automatically withdrawn when the finger placement bracket 32 is reset, so that there is no obstruction between the finger and the linear array camera 12, thereby ensuring the quality of fingerprint collection.

Optionally, a through hole is provided on the side of the shell 30 at a position corresponding to the finger placement area, and the automatic pop-up positioning mechanism pops out or resets through the through hole.

Optionally, the contactless finger and palm print collection device also includes: annular finger sleeves of different sizes, the annular finger sleeves are used to be put on the finger joints, the outer rings of the annular finger sleeves of different sizes match the automatic pop-up positioning mechanism, the inner rings of the annular finger sleeves of different sizes match the finger sizes of different thicknesses, the position of the annular finger sleeve on the finger corresponds to the position of the arc-shaped soft-glue finger positioning device 33, and the annular finger sleeve corresponds to the position of the shell 30 when the finger placement bracket 32 is reset.

The annular finger sleeve has a certain thickness, and the outer ring has the same size, which can be an ellipse, matching the arc inner wall of the arc-shaped soft-gel finger clamping device 33, and the inner ring is set to different sizes to adapt to different finger thicknesses. By matching and fixing the annular finger sleeve with the automatic pop-up positioning mechanism, not only can the finger be further kept in a fixed position during the collection process, but also the finger head can be controlled to be suspended in the air, avoiding the cross-transmission of germs caused by the use of the device by different people. During the fingerprint collection process, due to the small area where the finger is placed, it is difficult to clean. Through the use of disposable annular finger sleeves, the area where the fingerprint needs to contact the device during the collection process is separated by the annular finger sleeve, maintaining the hygiene of the collection environment, and the annular finger sleeve can be recycled, disinfected, and recycled.

In actual application, the finger placement bracket 32 pops up and fingerprint collection begins. The fingerprint of the specified finger can be collected through language or display prompts. When a suitable ring-shaped finger sleeve is put on the finger sleeve and placed in the correct position, the arc-shaped soft-glue finger positioning device 33 automatically descends to position the collected finger, the finger placement bracket 32 automatically resets, and the movable template 34 is automatically withdrawn, so that there is no obstruction between the collected finger and the linear array camera 12, and the rotating device 11 starts immediately, driving the linear array camera 12 to start rotating to scan and collect fingerprints.

Optionally, the shell 30 further includes a suction cup mounting bracket 35, on which a suction cup device is mounted. The suction cup device corresponds to the back of the finger, and the suction cup device fixes the back of the finger through the suction force generated by negative pressure.

Since the users of the fingerprint collection device are usually criminal suspects, in order to prevent the user from moving his fingers and affecting the fingerprint collection during the collection process, a suction cup device can be installed above the finger to suck the finger of the person being collected and prevent the finger from moving during the collection process. The suction cup device can correspond to the suction cup and the connected air pumping device, and the air pumping device can generate negative pressure in the suction cup area to suck the finger. Correspondingly, in order to maintain the hygiene of the equipment, the suction cup can also be replaced after a single use.

The second shooting mechanism 20 includes a moving device 21, an area array camera 22 installed on the moving device 21, and a second illumination light column 23 with a preset angle; the moving device 21 drives the area array camera 22 and the second illumination light column 23 to move parallel to the palm placement area and tilt toward the palm placement area at the stop positions on both sides, and triggers the area array camera 22 to shoot the palm print surface of the palm when moving to the center position of the palm and the stop positions on both sides, and the second illumination light column 23 is aimed at the photographed palm print surface.

By moving the area array camera 22 to photograph the main palm print and the side palm print, the physical contact mode between the palm and the optical device is changed, and the difficulty and time of collecting large-area and high-quality palm prints are reduced.

The second lighting light column 23 is pre-adjusted at an angle according to the distance between the area array camera 22 and the palm placement area and the installation position of the second lighting light column 23, so that the second lighting light column 23 moves synchronously with the area array camera 22, and the lighting area of the second lighting light column 23 is always aligned with the shooting area of the area array camera 22. As shown in the figure, multiple second lighting light columns 23 with preset angles are aligned with the area array camera 22 at the same shooting target position to increase the illumination. The second lighting light column 23 can be installed at a position and quantity according to actual needs.

Optionally, the moving device 21 includes a second installation platform 211, a second stepping motor 212, a second synchronous wheel, a second synchronous belt, and a second encoding pulse trigger.

The second stepper motor 212 has a second synchronous wheel and a second coded pulse trigger installed on its output shaft, and the second synchronous belt connects the second mounting platform 211 and the second synchronous wheel; the second coded pulse trigger sends a second pulse trigger signal according to the rotation of the second stepper motor 212, so as to trigger the area array camera to shoot; the second stepper motor 212 drives the second synchronous wheel to rotate, and the second synchronous wheel drives the second synchronous belt to drive, and the second synchronous belt drives the second mounting platform 211 to move and stop at the stop positions on both sides, and the second mounting platform 211 is used to install the area array camera 32 and the second illumination light column 33.

In practical applications, the second stepper motor 212 can be installed at the bottom of the housing 30, and the second mounting platform 211 can be driven to translate by the second synchronous wheel and the second synchronous belt, thereby driving the area array camera 22 and the second illumination light column 23 to translate as a whole. Although not shown in the figure, in practical applications, the gears and belts can be coordinated to pull the gears and belts under the transmission of the second synchronous belt to control the movement of the second mounting platform 211. Exemplarily, the second synchronous belt can be fixedly connected to one side of the second mounting platform 211, pass through the long strip structure at the bottom of the second mounting platform 211, bypass the second synchronous wheel, and then be fixedly connected to the other side of the second mounting platform 211, so that when the second synchronous wheel drives the second synchronous belt to drive, the second synchronous belt can drive the second mounting platform 211 to translate. Optionally, the translation of the second mounting platform 211 can also be achieved by means of a lead screw.

Optionally, in actual application, the second mounting platform 211 can not only be moved leftward or rightward or forward and backward on a horizontal plane to adjust the position, but can also be moved in a vertical direction to adjust the height.

The second coded pulse trigger is installed together with the output shaft of the second stepper motor. Exemplarily, the second stepper motor determines the number of rotations according to the position of the palm and adjusts the moving distance and position of the area array camera 22. The second coded pulse trigger triggers the area array camera 22 to shoot the main palm print when the area array camera 22 moves to the center position of the corresponding palm, triggers the area array camera 22 to shoot the side palm print when the area array camera 22 moves to a stop position on one side, and triggers the area array camera 22 to shoot the side palm print when the area array camera 22 moves to a stop position on the other side.

Optionally, the moving device 21 further includes a tilt control device, and the tilt control device is used to control the second mounting platform 211 to tilt to a preset tilt angle.

Exemplarily, the preset tilt angle may be about 45°.

Optionally, the tilt control device may be a micromotor disposed on the second mounting platform 211, which may control the movement of the second mounting platform 211 and adjust the rotation angle of the second mounting platform 211 so that the second mounting platform 211 tilts toward the corresponding palm side.

The second mounting platform 211 is rotatably mounted on the mobile device 21. When the mobile device 21 drives the area array camera 22 to move to the left stop position, the micromotor controls the second mounting platform 211 to rotate clockwise from the horizontal position to a preset tilt angle to photograph the palm prints on the left side of the palm. When the mobile device 21 drives the area array camera 22 to move to the right stop position, the micromotor controls the second mounting platform 211 to rotate counterclockwise from the horizontal position to a preset tilt angle to photograph the palm prints on the right side of the palm.

Optionally, the tilt control device may be two sliders disposed on both sides of the second mounting platform 211 , and used to lift the slider and a side corresponding to the second mounting platform 211 to a predetermined height according to a preset tilt angle of the second mounting platform 211 .

The second mounting platform 211 is rotatably mounted on the mobile device 21. When the mobile device 21 drives the area array camera 22 to move to the left stop position, the slider on the left lifts up the second mounting platform 211, so that the area array camera 22 tilts to the right to photograph the palm prints on the left side of the palm. When the mobile device 21 drives the area array camera 22 to move to the right stop position, the slider on the right lifts up the second mounting platform 211, so that the area array camera 22 tilts to the left to photograph the palm prints on the right side of the palm.

Optionally, the palm placement area on the housing 30 is a transparent support plane 36 , and the transparent support plane 36 is parallel to the shooting plane of the area array camera 22 on the second mounting platform 211 .

Optionally, the transparent support plane 36 may also be automatically popped out or reset to support the palm for capturing the palm print. In order for the area array camera 22 to capture clear palm prints, the palm needs to be parallel to the capturing surface of the area array camera 22, so that the transparent support plane 36 is set parallel to the capturing surface of the area array camera 22. In order to keep the equipment hygienic, the transparent support plane 36 may be disinfected and cleaned after a palm print capture is completed.

Optionally, the palm placement area is provided with photosensitive tubes arranged at a predetermined interval, and the photosensitive tubes are used to determine the size and position of the palm according to the number of photosensitive tubes blocked by the palm. For example, the photosensitive tube array is arranged at a spacing of 2 mm, and after the palm is placed, the size and position of the palm can be quickly calculated according to the number and position of the blocked photosensitive tubes, so as to determine the distance that the array camera needs to move to the center position and the stop positions on both sides.

The stop positions on both sides of the second mounting platform 211 are determined according to the size and position of the palm and the preset tilt angle of the second mounting platform 211 .

If the distance between the area array camera 22 and the palm placement area is fixed, the center point position is determined according to the acquired palm size and position, and the stop positions on both sides can be calculated according to the palm width and the preset tilt angle. When photographing the main palm print and the side palm print, the same shooting object distance needs to be maintained. The moving distance parameter of the mobile area array camera 22 is determined according to the actual palm size, and the moving distance of palms of different sizes can be calculated.

Optionally, a palm limiting device 37 is provided outside the palm placement area of the housing 30, and the palm limiting device includes four limiting rods corresponding to the base of the finger joints (between the thumb and the index finger, between the index finger and the middle finger, between the middle finger and the ring finger, and between the ring finger and the little finger), and is used to guide the palm to be placed in a preset position. The limiting device 37 can be automatically popped out when the palm print collection starts.

Optionally, the non-contact finger and palm print collection device further comprises an air bag 24, and the air bag 24 is used to automatically descend and press on the back of the hand after the palm is placed.

Optionally, after the palm is placed, the palm may be suspended in the air, resulting in failure to collect a clear palm print image. In order to ensure the collection quality, the palm can be pressed down and pressed against the collection device by the airbag 24. Optionally, the airbag 24 can be inflated and enlarged during use to squeeze the back of the hand, or it can be kept inflated and squeezed by lifting and lowering control.

In actual application, when palm print collection starts, a voice or display prompts to collect the specified palm print, and the support plane and limit device of the palm placement area pop up automatically. After the palm is placed in place, the support plane of the palm placement area automatically resets, waiting for the airbag to descend and press the back of the hand to make the back of the hand flat. At the same time, the area array camera is started to shoot the main palm print, and then the area array camera is moved to the stop position on both sides, and the area array camera is tilted to maintain the same shooting object distance as the main palm print, and the contralateral palm print is shot.

It should be noted that, in actual applications, the second shooting mechanism also includes necessary power supply device and control device. The power supply device is used to supply power for the operation of each component. The control device can receive the recognition result of the photosensitive tube, calculate the moving distance and stop position of the area array camera, control the operation and reset of the equipment, control the descent timing of the airbag, and control the tilt of the area array camera, etc.

Through the positioning device for limiting the placement of fingers, the positioning device for limiting the placement of palms, the palm size measuring device and the mechanism for airbag pressing the back of the hand, the repeatability of collecting fingerprints of the same finger and the palm prints of the same palm is greatly improved. And the fingerprint image can be restored most realistically through the linear array camera, without the need for image stitching, and without a lot of post-processing and adjustment through software.

The present application also provides a non-contact finger and palm print collection method, which is applied to the above-mentioned non-contact finger and palm print collection device. The method includes the following three parts.

Fingerprint data collection part:

The linear array camera and the first illumination beam are driven by the rotating device to rotate around the finger placement area by a predetermined angle from a preset initial position, and scan and shoot at the same time;

The fingerprint surface image collected by the linear array camera is transmitted to the host computer;

The fingerprint surface image of the finger is preprocessed by the host computer, including noise filtering, sharpness and saturation enhancement; the edge recognition is performed on the preprocessed fingerprint image to extract the main fingerprint area; the regional fingerprint image is normalized to limit the grayscale value, separate the foreground color and background color, enhance the fingerprint texture along the ridge direction, remove the holes and burrs in the fingerprint, and output the 2D fingerprint image after the texture is refined.

Palmprint data collection part:

The area array camera and the second illumination light column are driven by the moving device to move to the center of the palm placement area to capture the main palm print image, and the area array camera and the second illumination light column are driven by the moving device to move to the stop positions on both sides and tilted toward the palm placement area to capture the side palm print images on both sides respectively;

The main palm print image and the side palm print image taken by the area array camera are transmitted to the host computer, and the palm print surface image is obtained by splicing.

The palm print surface image is preprocessed by the host computer, including noise filtering, sharpness and saturation enhancement; the edge recognition is performed on the preprocessed palm print image to extract the main area of the palm print; the regional palm print image is normalized to limit the grayscale value, separate the foreground color and the background color, enhance the palm print pattern along the ridge direction, remove the holes and burrs in the palm print, and output the 2D palm print image after the texture is refined.

Data storage part;

The output 2D fingerprint image and 2D palm print image are stored in correspondence with the identity information of the person being collected through the host computer.

In summary, the contactless finger and palm print collection device and method provided by the present application uses a linear array camera to rotate around the fingerprint surface to scan and capture fingerprints in all directions, avoiding the problem of image stitching errors and large differences in image matching with the actual object caused by the need for a large amount of post-processing and adjustment of the image by multiple area array cameras or 3D depth cameras after shooting. The 2D fingerprint image of the finger fingerprint surface can be directly obtained to obtain higher image quality and a fingerprint image of a larger area; the main palm print and side palm print are captured by a movable area array camera, and the main palm print and side palm print images can be captured at one time without moving the palm; the two shooting mechanisms are integrated into one through a shell to form a comprehensive collection device for fingerprints, main palm prints, and side palm prints, which greatly improves the comprehensive collection performance of finger and palm prints.

In addition, by presetting a predetermined angle between the plane where the lens of the linear array camera is located and the axis direction of the finger, and tilting it toward the fingertip, the lines on the fingertip can be taken into account during the rotation and shooting process of the linear array camera.

In addition, by setting up ring-shaped finger sleeves of different sizes, since the outer ring of the ring-shaped finger sleeve matches the finger placement bracket, the inner ring is suitable for fingers of different thicknesses. Therefore, different finger sizes can be kept fixed on the finger placement bracket to avoid movement of the fingers during the collection process, thereby ensuring the image quality of fingerprint collection.

In addition, by fixing the back of the finger with a suction cup device, the finger can be further kept stationary, ensuring the image quality of fingerprint collection.

In addition, by pressing the back of the hand with the airbag, the palm can be prevented from being suspended in the air during the collection process, thus ensuring the quality of palm print collection.

The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implying the number of technical features indicated. Thus, the defined "first" and "second" features may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

A person of ordinary skill in the art will appreciate that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk, or an optical disk, etc.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims (11)

1. A non-contact finger and palm print collection device, characterized in that it comprises: a first photographing mechanism, a second photographing mechanism, and a shell; the first photographing mechanism and the second photographing mechanism are installed on a supporting structure in the shell, and a finger placement area and a palm placement area are provided on the outside of the shell, the finger placement area corresponds to the photographing position of the first photographing mechanism, and the palm placement area corresponds to the photographing position of the second photographing mechanism; The first shooting mechanism includes a rotating device, a linear array camera mounted on the rotating device, and a first lighting light column with a preset angle; the rotating device drives the linear array camera and the first lighting light column to rotate around the finger placement area, and triggers the linear array camera to scan and shoot the fingerprint surface of the finger during the rotation process, and the first lighting light column is aligned with the photographed fingerprint surface of the finger during the rotation process; The rotating device includes a first installation platform, a first stepper motor, a first synchronous wheel, a first synchronous belt, and a first encoding pulse trigger; the first synchronous wheel and the first encoding pulse trigger are installed on the output shaft of the first stepper motor, and the first synchronous belt connects the first installation platform and the first synchronous wheel; the first encoding pulse trigger sends a first pulse trigger signal according to the rotation of the first stepper motor, which is used to trigger the linear array camera to scan and shoot; the first stepper motor drives the first synchronous wheel to rotate, the first synchronous wheel drives the first synchronous belt to drive, the first synchronous belt drives the first installation platform to rotate, and the first installation platform is used to install the linear array camera and the first illumination light column; The second shooting mechanism includes a moving device, an area array camera mounted on the moving device, and a second lighting light column with a preset angle; the moving device drives the area array camera and the second lighting light column to move parallel to the palm placement area and tilt toward the palm placement area at the stop positions on both sides, and triggers the area array camera to shoot the palm print surface of the palm when moving to the center position of the palm and the stop positions on both sides, and the second lighting light column is aimed at the photographed palm print surface; The mobile device includes a second mounting platform, a second stepper motor, a second synchronous wheel, a second synchronous belt, and a second coded pulse trigger; the second synchronous wheel and the second coded pulse trigger are installed on the output shaft of the second stepper motor, and the second synchronous belt connects the second mounting platform and the second synchronous wheel; the second coded pulse trigger sends a second pulse trigger signal according to the rotation of the second stepper motor, so as to trigger the area array camera to take pictures; the second stepper motor drives the second synchronous wheel to rotate, and the second synchronous wheel drives the second synchronous belt to transmit, and the second synchronous belt drives the second mounting platform to move and stop at the stop positions on both sides, and the second mounting platform is used to install the area array camera and the second illumination light column. 2. The non-contact fingerprint and palm print collection device according to claim 1 is characterized in that a predetermined angle is preset between the plane where the lens of the linear array camera is located and the direction of the finger axis, and the side of the linear array camera close to the fingertip is inclined toward the fingertip. 3. The contactless finger and palm print collection device according to claim 1 or 2 is characterized in that an automatic pop-up positioning mechanism is provided in the finger placement area on the shell, and the automatic pop-up positioning mechanism includes a finger placement bracket that can pop out and automatically reset and an arc-shaped soft-glue finger clamping device, and the arc-shaped soft-glue finger clamping device is used to clamp the finger on the finger placement bracket, and the finger placement bracket is provided with a movable template corresponding to the fingertip position, and the movable template is automatically pulled out when the finger placement bracket is automatically reset. 4. The contactless finger and palm print collection device according to claim 3 is characterized in that it also includes: annular finger sleeves of different sizes, the annular finger sleeves are used to be sleeved on finger joints, the outer rings of the annular finger sleeves of different sizes match the automatic pop-up positioning mechanism, the inner rings of the annular finger sleeves of different sizes respectively match the finger sizes of different thicknesses, the position of the annular finger sleeve on the finger corresponds to the position of the arc-shaped soft-glue finger locking device, and the annular finger sleeve corresponds to the position of the shell when the finger placement bracket is reset. 5. The contactless fingerprint and palm print collection device according to claim 4 is characterized in that the shell also includes a suction cup mounting bracket, and a suction cup device is installed on the suction cup mounting bracket. The suction cup device corresponds to the back of the finger, and the suction cup device fixes the back of the finger through the suction force generated by negative pressure. 6. The non-contact fingerprint and palm print collection device according to claim 1, characterized in that the mobile device also includes a tilt control device, and the tilt control device is used to control the second mounting platform to tilt to a preset tilt angle. 7. The non-contact fingerprint and palm print collection device according to claim 6, characterized in that the palm placement area on the housing is a transparent support plane, and the transparent support plane is parallel to the shooting plane of the area array camera on the second mounting platform; The palm placement area is provided with photosensitive tubes arranged at a predetermined interval, and the photosensitive tubes are used to determine the size and position of the palm according to the number of photosensitive tubes blocked by the palm. 8. The non-contact fingerprint and palm print collection device according to claim 7, characterized in that the stop positions on both sides of the second mounting platform are determined according to the size and position of the palm and the preset inclination angle of the second mounting platform. 9. The contactless finger and palm print collection device according to any one of claims 1, 6 or 7 is characterized in that a palm limiting device is arranged outside the palm placement area of the shell, and the palm limiting device includes four limiting rods corresponding to the roots of the finger joints, which are used to guide the palm to be placed in a preset position. 10. The non-contact finger and palm print collection device according to claim 9, characterized in that the non-contact finger and palm print collection device also includes an air bag, and the air bag is used to automatically descend and press on the back of the hand after the palm is placed. 11. A non-contact finger and palm print collection method, characterized in that it is applied to the non-contact finger and palm print collection device according to any one of claims 1 to 10, and the method comprises: Fingerprint data collection part: The linear array camera and the first illumination beam are driven by the rotating device to rotate around the finger placement area by a predetermined angle from a preset initial position, and scan and shoot at the same time; Transmitting the fingerprint surface image collected by the linear array camera to the host computer; The upper computer preprocesses the fingerprint surface image, including noise filtering, sharpness and saturation enhancement; the preprocessed fingerprint image is edge-recognized to extract the main fingerprint area; the regional fingerprint image is normalized to limit the grayscale value, separate the foreground color and background color, enhance the fingerprint texture along the ridge direction, remove the holes and burrs in the fingerprint, and output the 2D fingerprint image after the texture is refined; Palmprint data collection part: The area array camera and the second illumination light column are driven by the moving device to move to the center of the palm placement area to capture the main palm print image, and the area array camera and the second illumination light column are driven by the moving device to move to the stop positions on both sides and tilted toward the palm placement area to capture the side palm print images on both sides respectively; The main palm print image and the side palm print image taken by the area array camera are transmitted to the host computer, and the palm print surface image is obtained by splicing and processing; The palm print surface image is preprocessed by the host computer, including noise filtering, sharpness and saturation enhancement; the edge recognition is performed on the preprocessed palm print image to extract the main area of the palm print; the regional palm print image is normalized to limit the gray value, separate the foreground color and the background color, enhance the palm print pattern along the ridge direction, remove the holes and burrs in the palm print, and output the 2D palm print image after the texture is refined; Data storage part; The output 2D fingerprint image and 2D palm print image are stored in correspondence with the identity information of the person being collected through the host computer.