KR20190097706A - Apparatus and method for contactless fingerprint recognition - Google Patents

Abstract

The present invention discloses a contactless fingerprint recognition device and a contactless fingerprint recognition method. According to one aspect of the present invention, the contactless fingerprint recognition device comprises a camera, at least one distance detection sensor, and a fingerprint recognition system. The fingerprint recognition system includes: a control module controlling the camera to photograph an image of a target based on at least one distance information measured by each of the at least one distance detection sensor; and a fingerprint recognition module performing fingerprint recognition based on the image of the target.

Description

Apparatus and method for contactless fingerprint recognition

The present invention relates to a contactless fingerprint recognition device and a contactless fingerprint recognition method.

Biometrics is a self-identification technology that identifies a user's identity based on human body characteristics. The methods of recognizing the information about the physical characteristics of human beings used in biometric technology include Fingerprint, Iris scan, Retina scan, Hand geometry, and Facial recognition. There is a way.

The most common in the biometric technology is fingerprint recognition, fingerprints formed on the human finger are all different, not only different from person to person, but also have characteristics that do not change for life as it is born, high reliability and stability of identification, It is also easy to store and collate information.

Conventional fingerprint recognition device for fingerprint recognition (fingerprint recognition device) has a glass surface (sensor) is formed on the top, the camera and the lighting is built in the configuration, the user's finger touches the glass surface (sensor) to operate the fingerprint reader The camera is configured to acquire a fingerprint image by photographing a finger. In addition, the fingerprint reader has a function of discriminating whether it is a fake fingerprint made of silicon, etc., rather than an actual human fingerprint (Live Finger Detection, LFD), a function of extracting and storing feature points of the ridge of the fingerprint (optimal recognition fingerprint data generation function). , Image Enhancement Feature Extraction Matching). The fingerprint reader is referred to as a contact (or optical) fingerprint reader. The fingerprint image photographed by the fingerprint reader is adjusted to obtain a clear flat fingerprint image by adjusting sharpness and contrast. From the feature points of the ridges of each fingerprint are extracted.

However, in the conventional fingerprint reader that has been commonly used, the finger touches the sensor (glass surface) in order to acquire a fingerprint. As the user uses the sensor, the sensor becomes contaminated or damaged and the recognition performance is deteriorated. Touching the sensor also negatively affected personal cleanliness.

In addition, the shape of the fingerprint may be distorted according to the strength of the pressure applied to the sensor when the contact is made, the shape of the fingerprint may be distorted as the finger slides on the contact surface of the sensor, and the difference between ambient temperature and humidity or the skin condition of the user (Eg, drying of the skin, degree of humidity), there was a problem such as unable to obtain a clear fingerprint image.

In order to solve the problem of the conventional optical fingerprint reader, a non-contact fingerprint recognition device has been developed in recent years, in which a user does not directly touch a finger with a sensor but photographs a little distance from a camera to obtain a fingerprint image. The technology of the contactless fingerprint reader and the fingerprint recognition method has been disclosed in Korean Patent Publication Nos. 0895247, 00604267, and 1274260.

In implementing a non-contact fingerprint recognition device, the form of a fingerprint is usually obtained by using an imaging device such as a camera. However, unlike the contact fingerprint system where the finger is physically in contact with the sensor and the finger is positioned at a certain place, in the non-contact fingerprint recognition system, since the finger is freely placed in the air, the position of the finger is not constant so that a valid image for fingerprint recognition can be obtained. Difficult to acquire

An object of the present invention is to provide a non-contact fingerprint recognition device and method for acquiring an image favorable for fingerprint recognition in order to improve fingerprint recognition performance.

In addition, the present invention is to provide a technical idea that can improve the recognition performance by assuming a virtual contact plane that the finger touches by recognizing the position and posture of the finger.

According to an aspect of the present invention, there is provided a camera, a distance sensing system including at least one distance sensing sensor, and a fingerprint recognition system, wherein the fingerprint system includes at least one measured by each of the at least one distance sensing sensor. A non-contact fingerprint recognition device is provided that includes a control module for controlling the camera to capture an image of an object based on distance information and a fingerprint recognition module for performing fingerprint recognition based on the image of the object.

In one embodiment, the non-contact fingerprint recognition device further comprises a guiding device, wherein the control module, the guiding device is predetermined based on at least one distance information measured by each of the at least one distance sensing sensor. It can be controlled to output the guide information of.

In an embodiment, the guiding apparatus includes a plurality of light emitters formed around the camera, and the control module is configured based on at least one distance information measured by each of the at least one distance sensing sensor. The operation of each of the plurality of light emitters can be controlled.

In an embodiment, the control module specifies at least one of a position and a posture of the object based on the at least one distance sensing information, and at least one of the position and the posture of the object in which the guiding device is specified. It can be controlled to output the corresponding guide information.

In one embodiment, the fingerprint recognition system further comprises a storage module for storing virtual contact surface information that can define a virtual contact surface located in the upper air of the camera, the distance detection system comprises at least three distance detection sensors The control module may further include specifying a position and a posture of the object based on three or more distance information measured by each of the three or more distance sensing sensors, and a relationship between the specified position and posture of the object and the virtual contact surface. When the camera satisfies a predetermined condition, the camera may control to capture an image of the object.

In an embodiment, the control module may control the camera to capture an image of an object when at least one distance information detected by each of the at least one distance detection sensor is within a predetermined distance range.

In one embodiment, the distance range may be defined by the focal length of the camera.

According to another embodiment of the present invention, as a non-contact fingerprint recognition method performed by a non-contact fingerprint recognition device, the non-contact fingerprint recognition device, the camera, a distance sensing system including at least one distance sensing sensor and a fingerprint recognition system The method may further include controlling the camera to capture an image of an object based on at least one distance information measured by each of the at least one distance sensing sensor. Provided is a non-contact fingerprint recognition method comprising performing, by a fingerprint recognition system, fingerprint recognition based on an image of the object.

In one embodiment, the non-contact fingerprint recognition device further comprises a guiding device, wherein the non-contact fingerprint recognition method, the fingerprint recognition system, the at least one distance information measured by each of the at least one distance sensing sensor. The method may further include controlling the guiding apparatus to output predetermined guide information based on the result.

In an embodiment, the guiding apparatus may include a plurality of light emitting bodies formed around the camera, and the controlling of the guiding apparatus to output predetermined guide information may include: And controlling the operation of each of the plurality of light emitters based on the at least one distance information measured.

The controlling of the guiding apparatus to output predetermined guide information may include specifying at least one of a position and a posture of the object based on the at least one distance sensing information and the guiding apparatus. The method may include controlling to output guide information corresponding to at least one of a position and a posture of the specified object.

In one embodiment, the fingerprint recognition system further comprises a storage module for storing virtual contact surface information that can define a virtual contact surface located in the upper air of the camera, the distance detection system comprises at least three distance detection sensors The controlling of the camera to capture an image of an object may include specifying a position and a posture of the object based on three or more distance information measured by each of the three or more distance sensing sensors, and specifying the specified object. The method may include controlling the camera to capture an image of the object when the relationship between the position and the posture and the virtual contact surface satisfies a predetermined condition.

In an embodiment, the controlling of the camera to capture an image of the object may include: when the at least one distance information detected by each of the at least one distance sensing sensor is within a predetermined distance range, the camera may take an image of the object. It may include controlling to shoot.

According to another aspect of the present invention, there is provided a computer program installed by a computing system to perform the above-described method.

According to an embodiment of the present invention, a non-contact fingerprint recognition device and a fingerprint recognition method capable of acquiring an image advantageous for fingerprint recognition may be provided.

According to an embodiment of the present invention, the recognition performance of the non-contact fingerprint recognition system can be improved by recognizing the position and posture of the finger and assuming a virtual contact plane that the finger touches. The virtual contact plane is a virtual plane that touches the finger, but does not exist in reality, but acts as a transparent window in the optical contact fingerprint recognition system and is a plane parallel to the first finger while touching the fingerprint area of the first finger. In the example, by adopting the concept of the virtual contact surface, the position and the direction of the finger can be obtained to obtain an image that can recognize the fingerprint most effectively in the non-contact fingerprint recognition system.

In addition, according to an embodiment of the present invention, the user may be guided so that the finger may touch the virtual contact plane.

BRIEF DESCRIPTION OF THE DRAWINGS In order to better understand the drawings cited in the detailed description of the invention, a brief description of each drawing is provided.
1 is a view schematically showing the configuration of a contactless fingerprint recognition device according to an embodiment of the present invention, Figure 2 is a view showing a fingerprint recognition device and an object according to an embodiment of the present invention.
3 is a block diagram showing a specific configuration of a fingerprint recognition system according to an embodiment of the present invention.
4A illustrates a case where an object is farther than a virtual contact surface.
4B is a diagram illustrating a case where an object is closer to a camera side than a virtual contact surface.
4C is a diagram illustrating a case in which an object is inclined based on a virtual contact surface.
4D is a diagram illustrating a case in which an object leaves a virtual contact surface.
5 is a diagram illustrating an example in which the guiding apparatus 300 is implemented in the form of a light emitter.
6 is a flowchart illustrating a contactless fingerprint recognition method according to an embodiment of the present invention.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all transformations, equivalents, and substitutes included in the spirit and scope of the present invention. In the following description of the present invention, if it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this specification, terms such as "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described in the specification, one or more other It is to be understood that the present invention does not exclude the possibility of the presence or the addition of features, numbers, steps, operations, components, parts, or a combination thereof.

In addition, in the present specification, when one component 'transmits' data to another component, the component may directly transmit the data to the other component, or through at least one other component. Means that the data may be transmitted to the other component. On the contrary, when one component 'directly transmits' data to another component, it means that the data is transmitted from the component to the other component without passing through the other component.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings denote like elements.

1 is a view schematically showing the configuration of a non-contact fingerprint recognition device (hereinafter referred to as a fingerprint recognition device) according to an embodiment of the present invention, Figure 2 is a fingerprint recognition device according to an embodiment of the present invention And a diagram illustrating an object.

The fingerprint recognition device 10 may provide a means for capturing an image of the object 20 and performing fingerprint recognition from the captured image. The object 20 may be a finger that is an object of fingerprint recognition. According to the technical spirit of the present invention to be described later, as shown in FIG. 2, the user does not touch the camera included in the fingerprint recognition device 10, and the fingerprint recognition is performed while placing the object (ie, a finger) at a spaced position. Can be performed.

1 and 2, the fingerprint recognition device 10 may include a camera 100, at least one distance sensing sensor (for example, 200-1 to 200-4), a guiding device 300, The fingerprint recognition system 400 may be configured.

The fingerprint recognition device 10 may include hardware resources and / or software necessary to implement the technical idea of the present invention, and necessarily means one physical component or one device. no. That is, the fingerprint recognition device 10 may mean a logical combination of hardware and / or software provided to implement the technical idea of the present invention. If necessary, the fingerprint recognition device 10 may be installed in devices spaced apart from each other. It may be implemented as a set of logical configurations for implementing the technical idea of the present invention by performing. In addition, the fingerprint recognition device 10 may refer to a set of components implemented for each function or role for implementing the technical idea of the present invention.

The camera 100 may capture an image of the object 20 under the control of the fingerprint recognition system 400.

At least one distance detecting sensor (or distance measuring sensor; for example, 200-1 to 200-4) is positioned at the periphery of the camera 100 as shown in FIG. 2, and corresponds to an object located in a vertical direction. The distance between the distance sensors can be measured. The distance measuring direction of the at least one distance detecting sensor 200-1 to 200-4 may be parallel to the photographing direction of the camera 100. In FIG. 2, the distance measured by each of the distance sensors 200-1 to 200-4 is represented by a dotted line.

According to an embodiment, each of the distance sensing sensors 200-1 to 200-4 may be an ultrasonic sensor, an infrared sensor, a lidar sensor, a radar sensor, or the like.

1 and 2 illustrate an embodiment in which the fingerprint recognition device 10 includes four distance sensors 200-1 to 200-4, the technical spirit of the present invention is limited thereto. No, there may be embodiments that include more or fewer distance sensing sensors.

The guiding apparatus 300 may output predetermined guide information under the control of the fingerprint recognition system 400. For example, when the object is too close or too far from the camera, information for correcting the distance from the camera may be output. Alternatively, when the object is biased left / right / before / after, information for correcting the position of the object may be output.

In one embodiment, the guiding apparatus 300 may be in the form of a display apparatus. Alternatively, it may be a form including at least one light emitter as described below. Alternatively, the guiding device 300 may be a device for outputting guide information in the form of sound.

The fingerprint recognition system 400 controls various components of the fingerprint recognition device 10 (for example, the camera 100, the position detection sensors 200-1 to 200-4, the guiding device 300, and the like). Fingerprint recognition may be performed by analyzing the image photographed by the camera 100.

In one embodiment, the fingerprint identification system 400 may be a computing system. In this case, the fingerprint recognition system 400 may be in the form of a combination of hardware and software.

3 is a block diagram showing a specific configuration of the fingerprint recognition system 400 of the present invention.

Referring to FIG. 3, the fingerprint recognition system 400 may include a control module 410 and a fingerprint recognition module 420. According to an embodiment, the fingerprint recognition system 400 may further include a storage module 430.

In addition, the term module in the present specification may mean a functional and structural combination of hardware for performing the technical idea of the present invention and software for driving the hardware. For example, the module may mean a logical unit of a predetermined code and a hardware resource for performing the predetermined code, and does not necessarily mean a physically connected code or a kind of hardware. May be easily inferred by the average expert in the art.

The control module 410 may control the functions and / or resources of the fingerprint recognition device 10 and / or the fingerprint recognition system 400.

The control module 410 controls the camera 100 to capture an image of an object based on at least one distance information measured by each of the at least one distance detecting sensor 200-1 to 200-4. Can be.

In one embodiment, the control module 410 when the at least one distance information detected by each of the at least one distance detection sensor (200-1 to 200-4) are all within a predetermined distance range the camera 100 ) To take an image of the object.

In this case, the distance range may be defined by the focal length of the camera 100. For example, the control module 410 has all the at least one distance information detected by each of the at least one distance detection sensor 200-1 to 200-4 is the focal length of the camera 100. When the focal length of the camera 100 + α, the camera 100 may control to capture an image of the object (α is a predefined margin value).

In another embodiment, the control module 410 may control the camera to capture an image of the object when the object 20 is positioned on a virtual contact surface that is assumed to be located in the upper air of the camera 100. Can be.

In this embodiment, since the position and posture of the object 20 should be sensed, the non-contact fingerprint recognition device 10 should include three or more distance sensors.

In addition, in the present embodiment, the fingerprint recognition system 400 may further include a storage module 430 for storing virtual contact surface information that may define a virtual contact surface located in the upper air of the camera 100. The virtual contact surface may be a virtual area located at a distance from the camera 100 by a predetermined distance (for example, the focal length of the camera) and having a predetermined shape and / or area.

Meanwhile, in the present embodiment, the control module 410 is the position of the object 20 based on the distance information measured by each of the three or more distance detection sensors (for example, 200-1 to 200-4). And a posture, and when the relationship between the specified position and posture of the object 20 and the virtual contact surface satisfies a predetermined condition, the camera may control to capture an image of the subject.

For example, when the distance between the object 20 and the virtual contact surface is less than or equal to a predetermined value, and the angle between the object and the virtual contact surface is less than or equal to a predetermined value, the control module 410 captures an image of the object. Can be controlled.

On the other hand, the control module 410 is guided by the guiding device 300 based on at least one distance information measured by each of the at least one distance detection sensor (200-1 to 200-4). Can be controlled to output.

That is, the control module 410 allows the user to position the object in a suitable position when the object 20 is in a position not suitable for fingerprint recognition or is in a position not suitable for fingerprint recognition. The guide information may be controlled to be output.

In an embodiment, the control module 410 specifies at least one of a position and a posture of the object based on the at least one distance sensing information, and the position and the position of the object in which the guiding device 300 is specified. It may be controlled to output guide information corresponding to at least one of the postures.

In one embodiment, the control module 410 may control to output the guide information for allowing the object to contact the virtual contact surface when the distance between the virtual contact surface is a predetermined value or more.

4A illustrates a case where the object 20 is farther than the virtual contact surface. As shown in FIG. 4A, when the object 20 is positioned above the virtual contact surface 30, all of the distance information measured by the distance sensing sensors 200-1 to 200-4 is larger than the height of the virtual contact surface. do. In this case, the control module 410 may provide guide information to allow the user to place the finger closer to the camera.

4B is a diagram illustrating a case in which the object 20 is closer to the camera 100 side than the virtual contact surface. As shown in FIG. 4B, when the object 20 is positioned below the virtual contact surface 30, all the distance information measured by the distance sensing sensors 200-1 to 200-4 is smaller than the height of the virtual contact surface. do. In this case, the control module 410 may provide guide information to allow the user to place the finger further away from the camera.

4C is a diagram illustrating a case in which an object is inclined based on a virtual contact surface. When the object is in the same posture as in FIG. 4C, the distance measured by one of the distance detecting sensors 200-4 and the distance information measured by the other distance detecting sensor 200-2 differ by more than a predetermined standard. I will. In this case, the control module 410 may provide guide information to the user to place the finger in parallel with the camera 100.

4D is a diagram illustrating a case in which an object leaves a virtual contact surface. In this case, the distance measured by some distance detecting sensor 200-2 is abnormally large. In this case, the control module 410 may provide the user with guide information to match the position of the finger with the camera 100.

Meanwhile, in one embodiment, the guiding apparatus 300 may be implemented in the form of a light emitter, an example of which is illustrated in FIG. 5. As illustrated in FIG. 5, the guiding apparatus 300 may include a plurality of light emitters (for example, 300-1 to 300-4) formed around the camera 100.

In this case, the control module 410 is based on the at least one distance information measured by each of the at least one distance detection sensor (200-1 to 200-4), the plurality of light emitters 300-1 to 300-. 4) Each operation can be controlled.

For example, the control module 410 controls the light emitter 300-1 adjacent to the position sensor 200-1 to emit light when the object 20 is biased toward the position sensor 200-1. The light emitter 300-3 positioned on the opposite side may be controlled to emit light.

Referring to FIG. 3 again, the fingerprint recognition module 420 may perform fingerprint recognition by analyzing an image of the object 20 captured by the camera 100.

6 is a flowchart illustrating a contactless fingerprint recognition method according to an embodiment of the present invention.

Referring to FIG. 6, each of the distance detection sensors 200-1 to 200-4 may measure a distance from the object 20 (S100).

The fingerprint recognition system 400 may determine whether at least one distance information measured by each of the at least one distance detection sensor satisfies a predetermined position condition and / or posture condition (S110).

If not satisfied, the fingerprint recognition system 400 may output the guide information so that the user can place the finger in the correct position in the correct position (S120).

If satisfied, the fingerprint recognition system 400 may acquire an image of the object 20 through the camera 100 (S130), and perform fingerprint recognition (S140).

The foregoing description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. .

Claims (14)

camera;
At least one distance sensing sensor; And
Including a fingerprint identification system,
The fingerprint system,
A control module for controlling the camera to capture an image of an object based on at least one distance information measured by each of the at least one distance sensor; And
Non-contact fingerprint recognition device comprising a fingerprint recognition module for performing a fingerprint recognition based on the image of the object.
The contactless fingerprint recognition device of claim 1, wherein
Further comprising a guiding device,
The control module,
And a non-contact fingerprint recognition device that controls the guiding device to output predetermined guide information based on at least one distance information measured by each of the at least one distance sensing sensor.
The method of claim 2,
The guiding device,
It includes a plurality of light emitters formed around the camera,
The control module,
And a non-contact fingerprint recognition device controlling the operation of each of the plurality of light emitters based on at least one distance information measured by each of the at least one distance sensing sensor.
The method of claim 2,
The control module,
Specify at least one of a position and a posture of the object based on the at least one distance sensing information,
And a guiding device for controlling guide information corresponding to at least one of a specified position and posture of the object.
The method of claim 1,
The contactless fingerprint recognition device includes three or more distance sensing sensors,
The fingerprint recognition system,
Further comprising a storage module for storing virtual contact surface information that can define a virtual contact surface located in the upper air of the camera,
The control module,
Specifying a position and a posture of the object based on three or more distance information measured by each of the three or more distance sensing sensors,
And a camera configured to control the camera to capture an image of the object when the relationship between the specified position and posture of the object and the virtual contact surface satisfies a predetermined condition.
The method of claim 1,
The control module,
And at least one distance information detected by each of the at least one distance detecting sensor is within a predetermined distance range, and controls the camera to capture an image of an object.
The method of claim 6,
And the distance range is defined by the focal length of the camera.
A contactless fingerprint recognition method performed by a contactless fingerprint reader,
The contactless fingerprint recognition device,
camera;
A distance sensing system comprising at least one distance sensing sensor; And
Including a fingerprint identification system,
The contactless fingerprint recognition method,
Controlling, by the fingerprint recognition system, the camera to capture an image of an object based on at least one distance information measured by each of the at least one distance sensing sensor; And
And performing, by the fingerprint recognition system, fingerprint recognition based on the image of the object.
The method of claim 8
The contactless fingerprint recognition device further includes a guiding device,
The contactless fingerprint recognition method,
And controlling, by the fingerprint recognition system, the guiding device to output predetermined guide information based on at least one distance information measured by each of the at least one distance sensing sensor.
The method of claim 9,
The guiding device,
It includes a plurality of light emitters formed around the camera,
The controlling of the guiding device to output predetermined guide information may include:
And controlling an operation of each of the plurality of light emitters based on at least one distance information measured by each of the at least one distance sensing sensor.
The method of claim 9,
The controlling of the guiding device to output predetermined guide information may include:
Specifying at least one of a position and a posture of the object based on the at least one distance sensing information; And
And controlling the guiding device to output guide information corresponding to at least one of a specified position and posture of the object.
The method of claim 8,
The contactless fingerprint recognition device includes three or more distance sensing sensors,
The fingerprint recognition system,
Further comprising a storage module for storing virtual contact surface information that can define a virtual contact surface located in the upper air of the camera,
The controlling of the camera to capture an image of the object may include:
Specifying a position and a posture of the object based on three or more distance information measured by each of the three or more distance sensing sensors; And
And controlling the camera to capture an image of the object when the relationship between the specified position and posture of the object and the virtual contact surface satisfies a predetermined condition.
The method of claim 8,
The controlling of the camera to capture an image of the object may include:
And controlling the camera to take an image of an object when at least one distance information detected by each of the at least one distance detection sensor is all within a predetermined distance range.
A computer program installed by a computing system to perform the method of any one of claims 8 to 13.

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