WO2020184763A1

WO2020184763A1 - Anti-spoofing method and system of device comprising fingerprint sensor

Info

Publication number: WO2020184763A1
Application number: PCT/KR2019/003049
Authority: WO
Inventors: 민원기
Original assignee: 민원기
Priority date: 2019-03-08
Filing date: 2019-03-15
Publication date: 2020-09-17
Also published as: CN113785291A; KR102146089B1

Abstract

An anti-spoofing method using a device comprising a fingerprint sensor is disclosed according to one disclosure of the present invention. More specifically, provided are an anti-spoofing method and device capable of enhancing the security of a device by arranging optical characteristics of a region of a cut filter layer of an optical fingerprint sensor so as to measure oxygen saturation, such that oxygen saturation can be measured while recognizing a user's fingerprint.

Description

Anti-spoofing method and system of device including fingerprint sensor

The present invention relates to a method and system for preventing spoofing of a mobile device using body information of a user using a fingerprint recognition sensor. In more detail, it relates to a method and apparatus for efficiently supporting anti-spoofing by measuring a user's oxygen saturation using a PPG sensor module (optical sensor module) mounted on a mobile terminal.

Due to the widespread use of satellite positioning systems by fixed and mobile communication systems, including mobile terminals such as cellular telephones, "spoofing", the use of counterfeit positioning signals to provide a false location to the device, is of increasing interest. have.

For example, wireless LAN access point (AP) spoofing attacks other systems by tricking the source IP address when transmitting packets, so the attacker can hide his or her information and avoid detection. In other words, wireless LAN AP spoofing is tricking an unauthorized person by changing their IP address to the IP address of a trusted host between two systems in a trust relationship, and can easily disable the service that authenticates with only the IP address. .

On the other hand, fingerprints are unique features in the human body and have immutability, uniqueness, and convenience that do not change throughout life. Currently, fingerprint identification technology is already widely applied to equipment such as collection systems, access control systems, and smartphones, and capacitive fingerprint identification technology is steadily spreading in application functions such as mobile phone fingerprint unlocking and mobile phone online fingerprint payment. The demand for the safety of fingerprints is also increasing. Fingerprint identification technology based on capacitance is at risk of cracking, and by acquiring a fingerprint image and printing a fake fingerprint using special materials, it can break the fingerprint identification function of various mobile phone models. Therefore, there is a need for a more secure fingerprint identification technology.

As a type of portable bio-signal measuring device, there is a PPG (photo plethysmo graphy) measuring device. Since the information on the degree of contraction of peripheral blood vessels and the increase or decrease in cardiac output is reflected in the photovoltaic pulse wave, the physiological state related to the arterial blood vessel may be identified, and may be mainly used as a diagnostic aid for a specific disease.

In general, the PPG signal can be measured from the user's finger or earlobe. That is, the detector detects light transmitted from the light source to the finger or earlobe, thereby detecting the user's PPG signal.

[Patent Literature]

(Patent Document 1) Japanese Patent Laid-Open Publication No. 2006-074104 (published on March 16, 2006)

The technical problem of the present invention can provide a method of performing anti-spoofing using fingerprint information, which is the user's biometric identification information, in order to prevent erroneous authentication due to a user who is erroneously recognized by spoofing.

A device that performs anti-spoofing through a fingerprint sensor may be provided by an initiation, and the device is included on one side of the device, a biometric sensor that simultaneously senses a plurality of biometric information of a user, and a fingerprint image obtained from the biometric sensor. And a security information generation unit that generates user security information by combining oxygen saturation, a memory that stores information on the biometric information of a user registered in advance, and whether the user is authentic by comparing the user security information with the biometric information of the user registered in advance. The biometric sensor may include a forgery determination unit that determines a user's fingerprint image, and a photo-plethysmography (PPG) sensor that measures a user's blood oxygen saturation.

According to one disclosure, the present invention can provide an anti-spoofing method using a device including a fingerprint sensor, and the present method simultaneously senses a plurality of biometric information of a user using a biometric sensor included on one side of the device. Steps, comprising the step of creating user security information by combining the fingerprint image and oxygen saturation obtained from the biometric sensor, and determining whether the user is authentic or not by comparing the user security information with the biometric information of the user registered in advance, The sensor may be characterized in that a fingerprint sensor that senses a user's fingerprint image and a photo-plethysmography (PPG) sensor that measures a user's blood oxygen saturation are combined.

According to another embodiment, a recording medium recording a program necessary for executing the method of the present invention may be included.

According to one disclosure, it is possible to enhance the security of a mobile terminal by detecting whether a fake fingerprint has been detected using a fingerprint and oxygen saturation, which are biometric identification information.

According to one disclosure, the mobile device may have a function of measuring oxygen saturation and user authentication at the same time, so that it is possible to perform identity authentication by measuring the oxygen saturation level using the mobile device and recognizing a fingerprint of a finger. Therefore, it is possible to perform user authentication more efficiently and stably while simultaneously and conveniently measuring the oxygen saturation level without requiring a separate oxygen saturation meter.

In addition, according to the present invention, a spoofing attack through fingerprint recognition can be prevented by increasing the accuracy of checking the correspondence between a user's registered fingerprint and the recognized fingerprint.

The present invention doubles security using not only fingerprints but also the user's oxygen saturation, so the security of the device can be enhanced. In addition, by mounting a filter having two optical characteristics in one filter, it is possible to complexly sense user biometric information, which is economical and efficient.

1 is a diagram illustrating a device including a fingerprint sensor of the present invention by way of example.

2 is a diagram for explaining the configuration of a device for performing anti-spoofing according to the present invention according to an embodiment.

3 is a view for explaining the structure of the biosensor of the present invention according to an embodiment.

4 is a diagram illustrating a configuration of a device including a pinhole layer according to an exemplary embodiment.

5 is a diagram for comparing a characteristic of a red signal and a characteristic of a near-infrared signal according to an embodiment.

6 is a diagram illustrating a change in oxygen saturation according to a ratio of a signal according to an exemplary embodiment.

7 is a graph showing a change in a light absorption coefficient according to a wavelength according to an exemplary embodiment.

8 is a diagram for describing a method of detecting a forged fingerprint according to an exemplary embodiment.

9 is a diagram for describing characteristics of pixels of a fingerprint sensor according to an exemplary embodiment.

As a device that performs anti-spoofing through a fingerprint sensor, a security information generation unit that generates user security information by combining a fingerprint image obtained from a biometric sensor and a user's blood oxygen saturation, and information on the biometric information of a user registered in advance It includes a memory to store and a forgery determination unit to determine whether the user is authentic or not.

In this case, the biometric sensor may be implemented by combining a fingerprint sensor that senses a user's fingerprint image and a photo-plethysmography (PPG) sensor that measures a user's blood oxygen saturation.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments disclosed below. In addition, parts irrelevant to the present invention are omitted in the drawings in order to clearly disclose the present invention, and the same or similar reference numerals denote the same or similar components in the drawings.

Objects and effects of the present invention may be naturally understood or more clearly understood by the following description, and the objects and effects of the present invention are not limited only by the following description.

Objects, features and advantages of the present invention will become more apparent through the following detailed description. In addition, in describing the present invention, when it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a device including a fingerprint sensor of the present invention by way of example. The device 100 includes a touch panel assembly including a biometric sensor. Device 100 includes other sensors 21 such as a camera. The device 100 may also include various buttons such as a side button that accepts user input. The touch panel assembly 10 may include a reinforcing cover glass 50 disposed on the support glass 54. A colored epoxy material layer 52 may be used to attach the cover glass 50 to the support glass 54. The ITO pattern 56 may be printed on the bottom or back of the support glass 54. The support glass may be arranged such that a hole 58 for receiving the fingerprint sensor module or device 20 is formed.

When recognizing a fingerprint, in applying an optical sensing technique, a light sensing element such as a photodiode and a light source such as a light emitting diode (LED) and laser diode (LD) are used as a fingerprint sensor. It can be integrated into the device in different ways.

The biometric sensor for recognizing a fingerprint may be designed to be applied to the front of the display or to a specific location of the device.

According to one disclosure, a device 100 that performs anti-spoofing through a fingerprint sensor may be provided.

In addition, a biometric sensor 110 that is included on one surface of the device 100 and simultaneously senses a plurality of biometric information of a user may be provided.

A security information generation unit 120 that generates user security information by combining a fingerprint image obtained from a biometric sensor and an oxygen saturation degree may be provided.

A memory 130 for storing information on biometric information of a user registered in advance by an initiation may be provided.

According to one disclosure, a forgery determination unit 140 may be provided that compares user security information and biometric information of a user registered in advance to determine whether the user is authentic or not.

The biometric sensor 110 may be characterized in that a fingerprint sensor 111 for sensing a user's fingerprint image and a photo-plethysmography (PPG) sensor 112 for measuring a user's blood oxygen saturation are combined.

In addition, the present invention is a differential CV amplifier that amplifies a PPG signal through a PPG sensor, a sample amplifier that separates the PPG signal into an IR signal and a RED signal, and removes the ambient noise signal, and an amplified IR signal and RED signal. It may include a measuring unit for analyzing the user's oxygen saturation.

The light-emitting unit may include at least one of an internal light source positioned in the display panel of the device 100 to emit light or an external light source positioned in the display cover glass of the device 100 to emit light.

In addition, the biometric sensor is composed of a touch sensor grouped by a plurality of fingerprint sensor 111 pixels, and the forgery determination unit 140 includes data obtained from each of the plurality of fingerprint sensor 111 pixels for determining the authenticity of the user. It may be characterized by using the user security information generated by.

In addition, the forgery determination unit 140 compares the user's fingerprint image with the previously registered fingerprint image to derive a first forgery determination value whether the matching rate of the fingerprint pattern is higher than a predetermined reference, and stores the blood oxygen saturation degree of the user in advance. It is characterized by comparing the blood oxygen saturation to derive a second counterfeit judgment value whether the error value corresponds to a predetermined reference value, and determining whether the user is authentic or not using the first counterfeit judgment value and the second counterfeit judgment value. have.

Accordingly, in the present invention, after firstly determining whether a fingerprint is used to determine whether the user is forged or not, the authenticity of the user may be identified, and then, it is possible to determine whether or not the second is forged using the oxygen saturation level of other user information. In addition, the fingerprint and oxygen saturation information can be combined and determined at once. Security can be strengthened by using complex information.

Therefore, it is possible to efficiently implement device security using user information registered in advance.

In addition, a fingerprint quality evaluation unit that divides a user's fingerprint image into blocks to determine a quality evaluation value, a filtering unit that filters the user's fingerprint image to obtain a filtered fingerprint image, and a filtered fingerprint. The fingerprint comparator may further include a fingerprint comparator configured to compare the image and a pre-registered fingerprint image to determine a similarity value, and a fingerprint authenticity determination unit configured to determine whether to forge a user's fingerprint based on the determined image quality evaluation value and the similarity value.

The above configurations can be implemented integrally by the control unit. The controller may mean a module for controlling the device 100 of the present invention.

When a fingerprint is in contact with the biometric sensor by the initiation, a finger recognition sensor that senses a user's finger and an actual user determination circuit that determines whether the acquired fingerprint image is a fingerprint of the user's real finger is further included. I can.

By using the finger recognition sensor, it is possible to determine whether a person who touches the fingerprint is a real person or another item for which the fingerprint is forged, thereby enhancing security.

According to one disclosure, the biometric sensor 110 is characterized in that a portion for recognizing a fingerprint and a portion for measuring the blood oxygen saturation of a user may be combined and present.

According to one disclosure, the fingerprint sensor 111 emits light of a specific frequency reflected on the user's fingerprint by a light emitting unit that irradiates light of a specific frequency to the user's fingerprint area and photodiodes formed by a plurality of sensor pixels. It may include a light receiving unit that senses and outputs an electrical signal having a fingerprint image, and a fingerprint image generation unit that generates a fingerprint image through signal processing on the electrical signal.

The PPG sensor 112 is a color filter that selectively passes light of the same color in order to selectively sense light having the same color and wavelength band for some of the photodiodes included in the light receiving unit of the fingerprint sensor 111 In order to selectively sense light having the same wavelength band in the infrared region and the Color Pass Filter, an infrared filter that selectively passes light having the same wavelength band in the infrared region is mounted. have.

According to one disclosure, the fingerprint sensor 111 uses an optical filter (Red-IR Cut Filter) that blocks light above the infrared band on the remaining photodiodes except for photodiodes equipped with color filters and infrared filters among photodiodes of the light receiving unit. It may be characterized by including.

Referring to FIG. 3, the structure of the biometric sensor 110 can be confirmed.

In the case of a fingerprint sensor using optics, there is a need to secure an optical filter layer that can remove more than the near-infrared band on top of the fingerprint sensor in order to secure authentication performance in outdoor light.

In addition, in order to perform the complex user authentication pursuant to the present invention, it is necessary to simultaneously measure the oxygen saturation in blood. At this time, in order to sense the oxygen saturation level or HRM in blood, light in the red color and near-infrared band is required. Therefore, there is a need for a filter capable of transmitting red color and near-infrared light in the optical filter layer serving as a cut filter.

Accordingly, a Red-IR cut filter 2020 can be formed on a plurality of photodiodes 2010 constituting the fingerprint sensor, and an IR Pass Filter is used to measure blood oxygen saturation inside the Red-IR cut filter 2020. (2030) and Red Pass Filter (2040) may be included.

In other words, by analyzing the light that has passed through the IR Pass Filter (2030) and the Red Pass Filter (2040), the oxygen saturation level in the blood is determined, and the user's fingerprint information is obtained by using the light that has passed through another Red-IR cut filter (2020). Can be identified.

Therefore, the present invention double security by using not only the fingerprint but also the user's oxygen saturation, the security of the device can be enhanced. In addition, by mounting a filter having two optical characteristics in one filter, it is possible to complexly sense user biometric information, which is economical and efficient.

Referring to FIG. 4, the device 100 may include a display panel 3110 and a fingerprint sensor 2120, and the fingerprint sensor 2120 may include a pinhole layer 3200 and a biometric sensor 110. According to exemplary embodiments, the fingerprint sensor 2120 may be packaged and attached to one surface of the display panel 3110.

The pinhole layer 3200 may include a plurality of pinholes, and each pinhole may form a focus of light reflected and transmitted by a fingerprint. In addition, the display panel 3110 may include LEDs that emit light of a plurality of colors. In addition, among the LEDs, LEDs that emit light of at least some of the plurality of colors may be used for a fingerprint sensing operation.

The biometric sensor 110 includes a plurality of sensor pixels corresponding to a plurality of pin holes, and each sensor pixel may include one or more photodiodes PD. In addition, according to an embodiment, a filter may be formed corresponding to each of a plurality of sensor pixels, and the same color filter (or a filter passing light of the same wavelength) may be formed corresponding to the sensor pixels. have. In the embodiment of FIG. 4, an example in which the red color filter CF_R is formed on the photodiode in the image sensor corresponding to the sensor pixel is illustrated.

Further, an example of a sensor pixel in which a near-infrared filter IF for efficiently passing near-infrared rays is formed is shown. In addition, a filter having an optical property may be applied to the remaining photodiodes to block light of an abnormal wavelength in the near-infrared band.

According to the embodiment shown in FIG. 4, even if light from all LEDs of the display panel 3110 is reflected to the fingerprint, the same color (or, through a mono filter filtering the same color in the biometric sensor 110) Wavelength) may be selectively provided to the photodiodes PD in the sensor pixel, so that the clarity of the fingerprint sensing result may be improved similarly to the above-described embodiment.

Meanwhile, in FIG. 4, a user's oxygen saturation may be measured using light in the infrared region passing through the near-infrared filter and light passing through the red filter. In addition, the present invention is a differential CV amplifier that amplifies a PPG signal through a PPG sensor, a sample amplifier that separates the PPG signal into an IR signal and a RED signal, and removes the ambient noise signal, and an amplified IR signal and RED signal. It may include a measuring unit for analyzing the user's oxygen saturation.

According to one disclosure, the pinhole layer may be positioned between the display panel and the biometric sensor. In addition, the pinhole layer may include a plurality of pinholes that form a focus in order to transmit light reflected by a user's fingerprint to the biometric sensor.

The plurality of pinholes may be arranged to correspond one-to-one with the plurality of biometric sensor pixels included in the biometric sensor.

5 is a diagram comparing characteristics of a red signal and a near-infrared signal.

Referring to FIG. 5, components of a red signal passing through the skin and a component of a near-infrared signal are shown. Both the red and near-infrared signals that have passed through the skin are composed of DC and AC components. In particular, the DC component of the near-infrared signal is larger than the DC component of the red signal, and the AC component of the near-infrared signal is larger than the AC component of the red signal. Oxygen saturation uses the difference in the response of oxygen hemoglobin and hemoglobin to the red signal and near-infrared signal, and uses the ratio of the signal calculated as follows.

(Where R is the ratio of the red signal to the near-infrared signal, S _R is the red signal, S _IR is the near-infrared signal, AC _R is the AC component of the red signal, DC _R is the DC component of the red signal, and AC _IR is the AC of the near-infrared signal. Component, DC _IR is the DC component of the near-infrared signal)

6 is a diagram showing a change in oxygen saturation according to a ratio of a signal.

Referring to FIG. 6, a change in oxygen saturation according to a ratio of a red signal and a near-infrared signal is shown. That is, it can be seen that oxygen saturation decreases as the size of the red signal increases compared to the near-infrared signal, and oxygen saturation increases as the size of the red signal decreases compared to the near-infrared signal. On the other hand, oxygen saturation is a criterion for determining heart function and lung function, and the oxygen saturation level approaches 100 in a normal person. Meanwhile, the relationship between the ratio of the red signal and the near-infrared signal and the oxygen saturation is as follows.

(Where, SpO ₂ is oxygen saturation, A is the y-intercept, B is the slope, R is the ratio of the signal)

7 is a graph showing a change in light absorption coefficient according to wavelength.

Referring to FIG. 7, changes in optical absorption coefficients of oxygen hemoglobin and hemoglobin according to wavelength are illustrated. That is, it can be seen that the light absorption coefficient of oxygen hemoglobin for a signal having a small wavelength is larger than that of hemoglobin, and for a signal having a large wavelength, the light absorption coefficient of oxygen hemoglobin is smaller than that of the hemoglobin. In particular, for a red signal having 640 to 690 nm, it can be seen that even if the wavelength is slightly changed, the difference in the light absorption coefficients of oxygen hemoglobin and hemoglobin is greatly changed.

According to one disclosure, oxygen saturation and fingerprints of a user may be simultaneously recognized using the biometric sensor of the present invention.

Oxygen saturation can be measured through a PPG sensor equipped with a red color filter and an infrared pass filter on the photodiode of the fingerprint sensor. It will be described in more detail below.

A photodiode equipped with a red color filter is referred to as a first light-emitting element, and a photodiode equipped with an in-pass filter in infrared is referred to as a second light-emitting element.

The first light emitting device may perform light output of a red signal. In addition, photodetection of a red signal may be performed through the red light receiving element. The first photodetection data detected by the light receiving device may be stored in a memory. Also, the current I ₂ applied to the second light emitting device may be increased by a unit size. In addition, the second light-emitting device may perform light output of a near-infrared signal. Photodetection of a near-infrared signal may be performed using a light receiving element. The second photodetection data detected by the light receiving element may be stored in a memory. Here, the unit size may be in units of ㎂.

It is determined whether the current (I ₁ ) applied to the first light-emitting device and the current (I ₂ ) applied to the second light-emitting device reach a set value, respectively, and if the first current (I ₁ ) and the second current (I _{2) are} If) does not reach the set value, the first current I ₁ is increased by a unit size and the second current I ₂ is increased by a unit size, and thus may be repeated. That is, the first current I ₁ and the second current I ₂ may be continuously increased until effective data necessary to analyze the characteristics of the oxygen saturation sensor is obtained.

If the first current I ₁ and the second current I ₂ each reach a set value, the first photo-detection data and the second photo-detection data may be analyzed.

That is, the rate of change of the first photodetection data value according to the increase of the first current I ₁ is analyzed (first analysis), and the rate of change of the second photodetection data value according to the increase of the second current I ₂ is determined. Analyze (second analysis). In addition, the difference between the rate of change of the first photodetection data value according to the increase of the first current I ₁ and the rate of change of the second photodetection data value according to the increase of the second current I ₂ is analyzed (3rd analysis ). In addition, the value of the first photodetection data for the first current I ₁ having a specific size is analyzed (4th analysis), and the second photodetection data for the second current I ₂ having the same size is analyzed. Analyze the value (analysis 5). In addition, the difference between the value of the first photodetection data for the first current I ₁ having a specific size and the second photodetection data for the second current I ₂ having the same size is analyzed (second 6 analysis).

Based on the analysis results, the method of calculating the previously stored oxygen saturation can be modified. That is, the oxygen saturation measurement algorithm (Equations 1 and 2) is modified to be suitable for an oxygen saturation measurement sensor having a new light output characteristic. The correction of the oxygen saturation measurement algorithm may be made comprehensively based on the first to sixth analysis results. Meanwhile, as described above, since the wavelength change of the red signal has the greatest influence on the oxygen saturation, the oxygen saturation measurement algorithm may be modified based on the first analysis and the fourth analysis. The microprocessor stores the modified oxygen saturation calculation method in a memory, and performs the calculation of the oxygen saturation degree with reference to the modified oxygen saturation degree calculation method.

The forgery determination unit 140 according to an embodiment includes a fingerprint sensor 111 that senses a user's fingerprint. The forgery determination unit 140 may obtain an input fingerprint image 115 in which a user's fingerprint is displayed through the fingerprint sensor 111. The user's fingerprint image 115 may be obtained in the form of a partial image capturing a part of the user's fingerprint.

The forgery determination unit 140 can recognize the user's fingerprint by comparing the fingerprint (hereinafter referred to as'input fingerprint') displayed on the user's fingerprint image 115 with the registered fingerprints displayed on the registered fingerprint images 121 to 123. I can. The registered fingerprint images 121, 122, and 123 may be stored in advance in the registered fingerprint database 120 through a fingerprint registration process. The registered fingerprint database 120 may be stored in a memory (not shown) included in the forgery determination unit 140 or may be stored in an external device (not shown) such as a server capable of communicating with the forgery determination unit 140. .

8 is a diagram for explaining a process of comparing the input fingerprint image 115 and the registered fingerprint image 123. 8, the forgery determination unit 140 may match the input fingerprint image 115 and the registered fingerprint image 123 to compare the input fingerprint image 115 and the registered fingerprint image 123. have. For example, the forgery determination unit 140 adjusts the size of the input fingerprint image 115 or adjusts the size of the input fingerprint image 115 so that a common area overlaps between the input fingerprint image 115 and the registered fingerprint image 123. ) Can be rotated and translated. The forgery determination unit 140 may calculate a similarity of the fingerprint pattern in the corresponding common area and determine a recognition result based on the calculated similarity.

If the input fingerprint image 115 senses a fake fingerprint, and the fingerprint patterns between the input fingerprint image 115 and the registered fingerprint image 123 are similar to each other, there is a possibility that authentication for the fake fingerprint will succeed. . In order to solve this misrecognition problem, it is necessary to determine whether the input fingerprint displayed on the input fingerprint image 115 is a fake fingerprint or a real fingerprint of a person. According to an embodiment, the forgery determination unit 140 may include a forged fingerprint detection device (not shown), and may determine whether the input fingerprint is a forged fingerprint through the forged fingerprint detection device.

According to one disclosure, a fingerprint sensor performing fingerprint sensing may include a characteristic of a capacitance included in the touch sensor. Pixels that detect a fingerprint by one disclosure may be configured with a narrower pitch than pixels of a general touch sensor. For example, there may be a plurality of pixels constituting the touch sensor. The fingerprint sensing pixels may be configured in plural, and several fingerprint sensing pixels may be grouped together. A sensor grouped by a plurality of pixels may be used as a touch sensor.

The plurality of fingerprint detection pixels is effective because detailed data of individual pixels can be used to detect a fake fingerprint. Each of the fingerprint sensing pixels may sense light to sense an electronic signal in which a fingerprint is secured.

The fingerprint sensing pixels may have a pitch of 200 μm or less. In this case, the pitch of the pixels of the touch sensor grouped by the plurality of fingerprint sensing pixels may be 2.0 mm or more.

According to an embodiment, in order to secure additional resolution of a fingerprint image, it is necessary to reduce a pitch of a fingerprint pixel. When the number of pixels of the fingerprint sensor decreases, a clear fingerprint image can be obtained. In addition, it is necessary to reduce the angle of view and reduce the pitch between pinholes by reducing the diameter of the pinhole of the pinhole layer.

Preferred embodiments of the present invention described above are disclosed for the purpose of illustration, and those skilled in the art with ordinary knowledge of the present invention will be able to make various modifications, changes and additions within the spirit and scope of the present invention. It should be seen as falling within the scope of the above claims.

If a person of ordinary skill in the art to which the present invention pertains, various substitutions, modifications and changes are possible within the scope of the technical spirit of the present invention, so that the present invention is described in the foregoing embodiments and the accompanying drawings. Is not limited by.

In the exemplary system described above, the methods are described on the basis of a flowchart as a series of steps or blocks, but the present invention is not limited to the order of the steps, and certain steps may occur in a different order or concurrently with the steps described above. I can. In addition, those skilled in the art will appreciate that the steps shown in the flowchart are not exclusive, other steps may be included, or one or more steps in the flowchart may be deleted without affecting the scope of the present invention.

According to one disclosure, the mobile device may have a function of measuring oxygen saturation and user authentication at the same time, so that the mobile device can be used to measure the oxygen saturation and recognize a fingerprint of a finger to perform identity authentication. Therefore, it is possible to perform user authentication more efficiently and stably while simultaneously and conveniently measuring the oxygen saturation level without requiring a separate oxygen saturation meter.

Claims

A biometric sensor included on one surface of the device and simultaneously sensing a plurality of biometric information of a user;

A security information generation unit for generating user security information by combining the fingerprint image obtained from the biometric sensor and the user's blood oxygen saturation;

A memory for storing information on biometric information of a user registered in advance; And

Including; a forgery determination unit for determining whether the authenticity of the user by comparing the user security information and the biometric information of the user registered in advance;

The biometric sensor is a device that performs anti-spoofing through a fingerprint sensor, characterized in that a fingerprint sensor that senses a user's fingerprint image and a photo-plethysmography (PPG) sensor that measures a user's blood oxygen saturation are combined.
The method of claim 1,

The fingerprint sensor,

A light emitting unit that irradiates light of a specific frequency onto the user's fingerprint area;

A light receiving unit configured to sense light of a specific frequency reflected on the user's fingerprint by a sensor pixel array formed of a plurality of photodiodes and output an electrical signal having a fingerprint image;

Includes; a fingerprint image generator for generating a fingerprint image through signal processing on the electrical signal,

The PPG sensor,

For some of the photodiodes included in the light receiving unit of the fingerprint sensor, a color pass filter selectively passing light of the same color in order to selectively sense light having the same color and wavelength band, and an infrared ray In order to selectively sense light having the same wavelength band, an infrared filter (IR Pass Filter) that selectively passes light having the same wavelength band in the infrared region is mounted, which performs anti-spoofing through a fingerprint sensor. device.
The method of claim 2,

The fingerprint sensor includes an optical filter (Red-IR Cut Filter) that blocks light above the infrared band on the photodiodes other than the photodiodes equipped with the color filter and the infrared filter among the photodiodes of the light receiving unit. A device that performs anti-spoofing through a fingerprint sensor.
The method of claim 2,

A differential C-V amplifier amplifying the PPG signal received through the PPG sensor;

A sample amplifier for separating the PPG signal into an IR signal and a RED signal and removing an ambient noise signal; And

A device for performing anti-spoofing through a fingerprint sensor further comprising; a measuring unit for analyzing the amplified IR signal and the RED signal to measure the oxygen saturation of the user.
The method of claim 2,

The light emitting unit,

Anti-spoofing is performed through a fingerprint sensor, characterized in that it includes at least one of an internal light source positioned in the display panel of the device to emit light or an external light source positioned in the display cover glass of the device to emit light Device.
The method of claim 1,

The biometric sensor,

It consists of a touch sensor grouped by a plurality of fingerprint sensor pixels,

The forgery determination unit,

A device for executing anti-spoofing through a fingerprint sensor, characterized in that using user security information generated by data obtained from each of the plurality of fingerprint sensor pixels to determine the authenticity of the user.
The method of claim 1,

The forgery determination unit,

Comparing the user's fingerprint image with the previously registered fingerprint image to derive a first forgery determination value whether the matching rate of the fingerprint pattern is higher than a predetermined criterion,

Comparing the user's blood oxygen saturation and pre-stored blood oxygen saturation to derive a second forgery determination value whether the error value corresponds to a predetermined reference value,

A device for executing anti-spoofing through a fingerprint sensor, characterized in that to determine whether the user is authentic or not using the first forgery determination value and the second forgery determination value.
The method of claim 1,

A fingerprint quality evaluation unit that divides the user's fingerprint image into blocks to determine a quality evaluation value;

A filtering unit that filters the user's fingerprint image to obtain a filtered fingerprint image;

A fingerprint comparison unit that compares the filtered fingerprint image with a previously registered fingerprint image to determine a similarity value; and

A device for performing anti-spoofing through a fingerprint sensor, further comprising: a fingerprint authenticity determination unit determining whether or not the user's fingerprint is forged based on the determined image quality evaluation value and the similarity value.
The method of claim 2,

A pinhole layer disposed between the display panel of the device and the biometric sensor, further comprising a pinhole layer including a plurality of pinholes that form a focus to transmit light reflected by the user's fingerprint to the biometric sensor,

The device for performing anti-spoofing through a fingerprint sensor, characterized in that the plurality of pinholes are arranged to correspond one-to-one with a plurality of biometric sensor pixels included in the biometric sensor.
The method of claim 1,

A finger recognition sensor that senses a user's finger when a fingerprint is in contact with the biometric sensor; And

A device for performing anti-spoofing through a fingerprint sensor, further comprising a; real user determination circuit for determining whether the acquired fingerprint image is a fingerprint of a user's real finger.
Simultaneously sensing a plurality of biometric information of a user by using a biometric sensor included in one surface of the device;

Generating user security information by combining the fingerprint image obtained from the biometric sensor and the user's blood oxygen saturation; And

Comprising the step of comparing the user security information and biometric information of the user registered in advance to determine whether the user is authentic or not

The biometric sensor is an anti-spoofing method using a device including a fingerprint sensor, characterized in that a fingerprint sensor for sensing a user's fingerprint image and a photo-plethysmography (PPG) sensor for measuring a user's blood oxygen saturation are combined.