NFC card with fingerprint authentication function compatible with smartphone

Abstract

To provide an NFC card with fingerprint authentication function compatible with smartphone, configured so that successful fingerprint authentication can be recognized by a smartphone with a non-contact IC card reader equipped therein.SOLUTION: An NFC card with fingerprint authentication function compatible with smartphone includes: a fingerprint sensor and a fingerprint authentication unit; a memory for storing fingerprint data for collation; a coil for receiving electricity from a non-contact IC card reader; and a first NFC chip having a function of NFC communication with the non-contact IC card reader. The fingerprint authentication unit collates fingerprint data read by the fingerprint sensor with the fingerprint data for collation stored in the memory, and notifies, when the same fingerprint is authenticated, the non-contact IC card reader from the first NFC chip through NFC communication. A second NFC chip is recognized at an initial response of the NFC communication, thereby continuously supplying electricity from the non-contact IC card reader to the coil.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an NFC card with a smartphone-compatible fingerprint authentication function that adds the functionality of a hardware token to a smartphone equipped with a contactless IC card reader to prevent SIM swap fraud and the like. More specifically, the present invention relates to an NFC card with a fingerprint authentication function that is an NFC card equipped with an NFC chip, which is an IC chip capable of communicating via NFC (Near Field Communication), and that adds a fingerprint authentication function to the NFC card, making it compatible with smartphones and allowing fingerprint authentication to be used as one of the authentication methods for multi-factor authentication. [Background technology]

[0002] In recent years, smartphones have been used in various fields. To prevent unauthorized use of smartphones by others, smartphones are equipped with several identity verification functions. For example, they can be locked to prevent operation after a certain amount of time has passed since the start of operation, so that others cannot use them. It has become commonplace for smartphones to be equipped with biometric authentication functions such as fingerprint authentication and face authentication, which are more secure than password authentication, such as entering a four-digit number to unlock the smartphone. In addition to unlocking the smartphone, these biometric authentication functions are increasingly being used for identity verification when paying for online shopping.

[0003] In recent years, damage caused by cyber attacks has been increasing rapidly. The most notable damages to individuals are phishing scams, and to corporations are ransomware attacks. Phishing scams involve sending emails from spoofed senders, directing victims to fake websites in order to steal personal information such as passwords and credit card information.

[0004] Ransomware is a type of malware that invades a target's system by using passwords obtained through phishing scams, etc., and then encrypts the data and demands a ransom. When considering the method of intrusion, there are an increasing number of cases where the vulnerability of network devices is exploited to invade internal networks, but even in these cases, security is breached by using passwords that have been leaked in the past or by using a brute force attack to find out the password.

[0005] As such, traditional authentication methods using IDs and passwords alone cannot be considered secure against cyber attacks, and there is a growing opinion that we should switch to passwordless authentication, which does not use passwords, or multi-factor authentication, which combines several authentication methods. FIDO2 and Passkey are becoming standardized as passwordless authentication, and biometric authentication functions such as fingerprint and face recognition built into smartphones can be used as authentication devices, so it can be used without purchasing new hardware. Furthermore, in addition to authentication using a smartphone, FIDO2 allows authentication using the biometric authentication function built into the smartphone when connecting the PC and smartphone via Bluetooth (registered trademark).

[0006] One-time passwords used in online banking and other applications have traditionally been provided by hardware tokens. However, due to the battery life that runs the internal clock, these need to be replaced every few years. It is inconvenient to carry a hardware token to each bank when using online banking on a smartphone. For this reason, many authentication functions are now built into smartphones, such as providing one-time password functions as software authentication apps that can be installed on smartphones.

[0007] Currently, the switch to passwordless authentication and multi-factor authentication is progressing rapidly as a countermeasure against phishing scams. This has had a deterrent effect against phishing scams. However, a new cyber attack method called SIM swap fraud is beginning to cause damage. In SIM swap fraud, the criminal first obtains the personal information of the target victim through phishing or other methods, and then prepares a counterfeit driver's license or other document. Then, the criminal impersonates the victim and reports the loss of the smartphone to the mobile phone carrier, and takes over the victim's phone number by having the SIM reissued or other methods.

[0008] By hijacking a phone number, the criminal can receive all SMS and calls addressed to the victim. This allows them to circumvent SMS authentication, which is widely used for two-step authentication. Even for SNS accounts that do not use SMS authentication, the criminal can change the password by resetting the password using SMS authentication. Some people say that SMS authentication is risky for SIM swap scams, so we should switch to authentication apps. However, the reality is that too few people understand that this type of opinion is a mistaken opinion derived from a naive understanding of SIM swap scams.

[0009] When changing the model of the authentication app installed on a smartphone, it is normal to reinstall the authentication app and authenticate with the registered phone number, etc. This allows the app to be used in the same way as before the model change. In other words, the current situation is that security is built on the premise that "the person who has the phone number is the person himself." The perpetrator of a SIM swap can exploit this to easily reinstall the authentication app on the new device and perform authentication. As can be easily understood from the above explanation, authentication using an authentication app cannot prevent SIM swap fraud.

[0010] Similarly, with biometric authentication such as fingerprint or face recognition built into smartphones, when changing the model, biometric authentication is possible by reinstalling the application software and authenticating with the registered phone number, etc. It is important to understand that it is easy for a criminal who swaps SIMs to register his or her own biometric information on a new device. A criminal who swaps SIMs can successfully authenticate with his or her own biometric information. The scary thing is that biometric authentication built into smartphones cannot prevent SIM swap fraud.

[0011] Therefore, when a SIM swap is performed, most authentication methods such as biometric authentication and authentication apps on smartphones can be invalidated. In other words, the current situation is extremely dangerous. This is because, as mentioned above, security has been built on the assumption that "it is the person who has the phone number" in previous authentication methods. Security cannot be ensured on the assumption that "it is the person who has the phone number." Therefore, it is urgent to understand the laxity of this awareness and fundamentally reconstruct security based on the perspective that "it is possible for a malicious third party to have a phone number" through SIM swap. Unfortunately, a correct understanding of SIM swap is not widely known, and the current situation is that the only measures proposed are measures such as stricter identity verification when reissuing SIMs by mobile phone carriers.

[0012] Furthermore, until now, SIM swap fraud has mostly involved the theft of personal bank deposits and virtual currencies, and therefore was thought to have little to do with the security of large corporate networks. In August 2023, the US Department of Homeland Security reportedly released a report summarizing the results of the Cyber ​​Security Review Board's investigation into the threat actor "Lapsus$." According to the report, "Lapsus$" has successfully infiltrated dozens of organizations, including Microsoft in the United States, by making full use of attack methods such as SIM swapping. As can be seen from this report, the SIM swap method is not only being used in "SIM swap fraud" targeting personal assets, but is actually beginning to be used as a "SIM swap attack" to break through multi-factor authentication when infiltrating the networks of large companies. It is necessary to quickly popularize multi-factor authentication methods that can counter SIM swap attacks. Summary of the Invention [Problem to be solved by the invention]

[0013] SIM swap attacks mainly disable the biometric authentication built into smartphones and authentication apps installed on smartphones. If the authentication function is provided by hardware independent of the smartphone, even if the victim's phone number is transferred from the victim's smartphone to another smartphone by SIM swapping, the perpetrator cannot succeed in authentication because the hardware with the authentication function is in the victim's possession. Therefore, SIM swap attacks can be prevented by using authentication using hardware with authentication function, i.e., a hardware token, as one of the multi-factor authentication methods.

[0014] There are several types of hardware tokens. However, there were no convenient ones for multi-factor authentication on smartphones. For the type that uses a one-time password, you need to input the numbers displayed on the hardware token into your smartphone. For the type that connects via USB, you don't need to input numbers, and some of them incorporate biometric authentication functions such as fingerprint authentication. However, you need to connect the smartphone and the hardware token via a wired connection. Smartphones have a connector for wired connection that also serves as a charger. If you use this connector to connect the hardware token via a wired connection, you need to connect the cable or directly every time you authenticate. As you can see from the above explanation, a cable connection is not convenient, and if you connect directly, there is a high possibility that the hardware token or the smartphone will be damaged if the smartphone is dropped. Therefore, a USB-connected hardware token is not practical for multi-factor authentication on smartphones.

[0015] The inventors of the present application considered that it would be best to connect to a hardware token using NFC communication using a contactless IC card reader that is installed in most smartphones. In the case of NFC communication, power can be supplied from the contactless IC card reader of the smartphone. This means that there is no need to install a battery on the hardware token, and there is no need to replace the hardware token every few years, and maintenance such as charging is also unnecessary. Since the communication distance of NFC is shorter than that of Bluetooth, there is less risk of communication interception. In addition, NFC cards with fingerprint authentication function using an extremely thin capacitive fingerprint sensor are commercially available, and fingerprint authentication can also be used as multi-factor authentication.

[0016] There are two main types of NFC cards with fingerprint authentication currently on the market. One is designed for security purposes, and the other is designed for credit cards. The former, that is, NFC cards with fingerprint authentication designed for security purposes, only function as an NFC card if fingerprint authentication is successful, and have the advantage that they cannot be skimmed if fingerprint authentication is not successful. In addition, since they do not have a battery, a contactless IC card reader that can be continuously powered is required, but fingerprint authentication functions can be added to electronic locks, entrance and exit management systems, attendance management systems, etc. that use NFC cards without modifying the system.

[0017] The latter, that is, NFC cards with fingerprint authentication functions made for credit cards, have an NFC chip that can operate even without fingerprint authentication. This poses the risk of skimming. In addition, the same UID (fixed ID number) is output both before and after fingerprint authentication is successful. For this reason, systems must be changed in order to use electronic locks, entrance / exit management systems, attendance management systems, etc. that use NFC cards. Furthermore, with the iPhone (registered trademark), a smartphone from Apple Inc. in the United States, it is difficult to confirm that fingerprint authentication has been successful due to iOS restrictions.

[0018] Therefore, the inventors of the present application created application software to be applied to iPhones using an NFC card with a fingerprint authentication function, which was designed for security purposes, as a hardware token, and verified whether it could actually work. As a result of this verification, it was found that due to the limitations of the OS, the application software alone could not provide continuous power supply to complete fingerprint authentication with an NFC card with a fingerprint authentication function that does not have a built-in battery, and it could not be read as an NFC card. Therefore, it was not possible to perform fingerprint authentication using an iPhone with an NFC card with a fingerprint authentication function and prevent SIM swap attacks as a hardware token with biometric authentication.

[0019] The object of the present invention is to provide a smartphone-compatible NFC card with fingerprint authentication function as a hardware token that prevents SIM swap attacks by enabling continuous power supply from the contactless IC card reader by having the contactless IC card reader recognize a second NFC chip added to an NFC card with fingerprint authentication function for smartphone models that cannot receive continuous power from the contactless IC card reader using only the installed application software, performing fingerprint authentication with the NFC card with fingerprint authentication function, and enabling NFC communication with the first NFC chip that operates when fingerprint authentication is successful. [Means for solving the problem]

[0020] According to one aspect of the present invention, the above problem is solved by: An NFC card with a smartphone-compatible fingerprint authentication function that can recognize successful fingerprint authentication on a smartphone with a built-in contactless IC card reader, A fingerprint sensor; A fingerprint authentication unit; A memory for storing fingerprint data for matching; A first coil that receives power from the non-contact IC card reader; a fingerprint authentication means including a first NFC chip having a function of performing NFC communication with the non-contact IC card reader; The fingerprint authentication means includes: a fingerprint data reading function that starts reading fingerprint data using the fingerprint sensor when the first coil receives power from the non-contact IC card reader; a fingerprint data matching function for matching the read fingerprint data with the matching fingerprint data stored in the memory by the fingerprint authentication unit; a fingerprint authentication notification function for notifying the non-contact IC card reader that the fingerprints have been authenticated as the same fingerprint by the fingerprint authentication unit, by allowing the first NFC chip to perform the NFC communication only when the fingerprint authentication unit authenticates the fingerprints as the same fingerprint, the fingerprint sensor, the fingerprint authentication unit, the memory, and the first NFC chip operate only with power received by the first coil; The smartphone is a model in which the application software installed thereon alone cannot continuously supply power from the contactless IC card reader to the first coil, a second NFC chip separate from the first NFC chip; This is achieved by providing an NFC card with a smartphone-compatible fingerprint authentication function, which is characterized in that when the first coil receives power from the contactless IC card reader, the second NFC chip is recognized in the initial response of the NFC communication, thereby continuously supplying power from the contactless IC card reader to the first coil.

[0021] According to another aspect of the present invention, the above object is achieved by An NFC card with a smartphone-compatible fingerprint authentication function that can recognize successful fingerprint authentication on a smartphone with a built-in contactless IC card reader, A fingerprint sensor; A fingerprint authentication unit; A memory for storing fingerprint data for matching; A first coil that receives power from the non-contact IC card reader; a fingerprint authentication means including a first NFC chip having a function of performing NFC communication with the non-contact IC card reader; The fingerprint authentication means includes: a fingerprint data reading function that starts reading fingerprint data using the fingerprint sensor when the first coil receives power from the non-contact IC card reader; a fingerprint data matching function for matching the read fingerprint data with the matching fingerprint data stored in the memory by the fingerprint authentication unit; a fingerprint authentication notification function for notifying the non-contact IC card reader that the fingerprints have been authenticated as the same fingerprint by the fingerprint authentication unit, by allowing the first NFC chip to perform the NFC communication only when the fingerprint authentication unit authenticates the fingerprints as the same fingerprint, The smartphone is a model in which the application software installed thereon alone cannot continuously supply power from the contactless IC card reader to the first coil, a second NFC chip separate from the first NFC chip; a second coil separate from the first coil; the fingerprint sensor, the fingerprint authentication unit, the memory, and the first NFC chip operate only with power received by the first coil or the second coil; This is achieved by providing an NFC card with a smartphone-compatible fingerprint authentication function, which is characterized in that when the second coil receives power from the contactless IC card reader, the second NFC chip is recognized in the initial response of the NFC communication, thereby continuously supplying power from the contactless IC card reader to the first coil.

[0022] That is, in the present invention, the fingerprint authentication means mounted on the smartphone-compatible NFC card with fingerprint authentication function starts fingerprint authentication by wireless power supply from a contactless IC card reader built into the smartphone, and the contactless IC card reader communicates with the first NFC chip built into the smartphone-compatible NFC card with fingerprint authentication function via NFC, whereby the smartphone recognizes that the fingerprint has been authenticated as the same. Even in a model in which the application software installed on the smartphone alone cannot supply continuous power required for this fingerprint authentication means, continuous power supply is possible by having the second NFC chip recognized in the initial response of the NFC communication at the start of power supply.

[0023] According to a preferred embodiment of the present invention, the smartphone confirms that data using unique data on the smartphone-compatible NFC card with fingerprint authentication function matches the registered data on the smartphone. This provides high security based on two-factor authentication. The electronic circuit on the smartphone-compatible NFC card with fingerprint authentication function operates only with power supplied wirelessly from a contactless IC card reader. This eliminates the need to install a battery on the smartphone-compatible NFC card with fingerprint authentication function, and eliminates problems such as maintenance such as charging and battery deterioration.

[0024] According to another preferred embodiment of the present invention, an NFC card with a smartphone-compatible fingerprint authentication function can be used while stored in a smartphone case, or the size of the card can be made smaller than a credit card size to avoid protruding parts such as a smartphone camera lens and can be used while attached to the smartphone, allowing the card to be used in an integrated state with almost no increase in the thickness of the smartphone, and providing the same functionality and ease of use as a fingerprint authentication device built into a smartphone.

[0025] In recent years, contactless IC card readers for smartphones are required not only to read cards but also to perform NFC communication with various external devices for electronic money payments, etc. Even when an NFC card with a smartphone-compatible fingerprint authentication function is integrated with a smartphone, the embodiment of the present invention allows the smartphone to be used without interfering with NFC communication when the contactless IC card reader performs NFC communication with other IC cards or when performing NFC communication with various external devices including an external contactless IC card reader. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 is a block diagram of a fingerprint authentication system related to the present invention. [Diagram 2]11 is a flowchart for explaining an example of the operation of application software installed on a smartphone to control a fingerprint authentication system related to the present invention from the smartphone side. [Diagram 3] 4 is a timing chart of a first example illustrating a state of power supply to a coil. [Figure 4] 10 is a timing chart of a second example for explaining a state of power supply to a coil. [Diagram 5] 13 is a timing chart of a third example illustrating a state of power supply to a coil. [Figure 6] 13 is a timing chart of a fourth example illustrating a state of power supply to a coil. [Figure 7] FIG. 1 is an explanatory diagram of an example in which an NFC card with fingerprint authentication function of the present invention is attached to a smartphone. [Figure 8] 1 is a cross-sectional view for explaining a fingerprint authentication system related to the present invention. [Figure 9] 1 is a cross-sectional view for explaining a fingerprint authentication system related to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0027] FIG. 1 is a block diagram of a fingerprint authentication system related to the present invention. In the figure, reference symbol 1 is an NFC card with a smartphone-compatible fingerprint authentication function. Reference symbol 2 is a thin-shaped capacitive fingerprint sensor. Reference symbol 3 is a fingerprint authentication unit. Reference symbol 4 is a memory that stores fingerprint data for matching. Reference symbol 5 is a first coil that receives power from a non-contact IC card reader. Reference symbol 6 is a first NFC chip with a function of NFC communication, typically a FeliCa (registered trademark) chip. Reference symbol 7 is a second coil that receives power from a non-contact IC card reader. Reference symbol 8 is a second NFC chip with a function of NFC communication, typically a FeliCa chip. Reference symbol 9 is a smartphone that cooperates with the smartphone-compatible NFC card with a fingerprint authentication function 1. Reference symbol 10 is a non-contact IC card reader built into the smartphone 9, and reference symbol 11 is a user's finger whose fingerprint has been registered.

[0028] In the embodiment of the present invention shown in Fig. 1, in the illustrated fingerprint authentication system, the devices mounted on the smartphone-compatible NFC card 1 with fingerprint authentication function, i.e., the fingerprint sensor 2, the fingerprint authentication unit 3, the memory 4 that stores fingerprint data for collation, the first coil 5, and the first NFC chip 6, constitute the fingerprint authentication means Fp. The fingerprint authentication means Fp has basically the same configuration as that built into an NFC card with fingerprint authentication function designed for security purposes. In the embodiment of the present invention, a second coil 7 and a second NFC chip 8 are added to the fingerprint authentication means Fp.

[0029] A typical NFC chip has two external terminals, which are connected to both ends of a coil. The coil receives power from the contactless IC card reader and also plays the role of an antenna for NFC communication. Some NFC cards use part of the coil as an antenna pattern to increase the sensitivity of transmission and reception. When two NFC chips are mounted in a card, if only one coil is mounted, the two terminals of the two NFC chips will be directly connected, which may cause problems in NFC communication. Therefore, in the embodiment of the present invention, two coils (first coil 5 and second coil 7) are mounted, in which case there is no problem with NFC communication, and since the coils are made from a metal foil pattern on a printed circuit board, the cost does not increase even if there are two coils. The timing at which these two coils receive power from the contactless IC card reader is the same.

[0030] Depending on the specifications of the NFC chip and the timing of operating the two chips, it may be possible to design two NFC chips to be able to perform NFC communication with one coil without any problems. Whether to mount two coils or combine them into one in the embodiment of the present invention is merely a design matter for the designer of the NFC card. In the embodiment of the present invention, the first coil 5 is connected to the first NFC chip 6 and supplies power to the fingerprint authentication means Fp including the first NFC chip 6. Also, the second coil 7 is connected to the second NFC chip 8 and supplies power to the second NFC chip 8, but the present invention is not limited to this.

[0031] In the fingerprint authentication means Fp, on condition that power is supplied to the first coil 5 from the non-contact IC card reader 10 built into the smartphone 9, the powered first coil 5 supplies power to the fingerprint sensor 2, the fingerprint authentication unit 3, the memory 4, etc., and fingerprint authentication is started. At this time, the fingerprint authentication unit 3 controls the first NFC chip 6 so that it does not operate, for example by stopping the power supply to the first NFC chip 6.

[0032] After fingerprint authentication has started, when a finger 10 whose fingerprint has been registered in advance touches the fingerprint sensor 2, the fingerprint authentication unit 3 compares the fingerprint data of the finger 10 read from the fingerprint sensor 2 with the fingerprint data for comparison stored in the memory 4. If the fingerprints are recognized as identical through this comparison, the first NFC chip 6 is controlled to operate. This enables the non-contact IC card reader 10 to read the IDm1 data from the first NFC chip 6. This state is maintained until power supply to the first coil 5 is stopped.

[0033] On the other hand, before fingerprint authentication or when the fingerprint is not authenticated as the same, the fingerprint authentication unit 3 controls the first NFC chip 6 not to operate, and the state in which the IDm1 data cannot be read is maintained. By the above-mentioned control, the IDm1 data in the first NFC chip 6 can be read by the non-contact IC card reader 10 only when the fingerprint is authenticated as the same. In other words, when the fingerprint is not authenticated as the same, the IDm1 data in the first NFC chip 6 cannot be read by the non-contact IC card reader 10.

[0034] First, the IDm1 data in the first NFC chip 6 can be read by the non-contact IC card reader 10, and second, only when two conditions are satisfied that the IDm1 data registered in advance in the smartphone 9 matches the IDm1 data in the first NFC chip 6, the smartphone 9 is configured to recognize that "fingerprint authentication was successful with the smartphone-compatible NFC card 1 with fingerprint authentication function." In this case, the smartphone 9 performs authentication using two factors, the fingerprint and the IDm data in the NFC chip, providing higher security than simple fingerprint authentication.

[0035] 1, a FeliCa chip is used as the first NFC chip 6 that performs NFC communication with the non-contact IC card reader 10. For example, since the non-contact IC card reader 10 supports wireless communication based on the NFC standard, an NFC chip based on another NFC standard, such as Mifare (registered trademark), may be used as long as it is an NFC chip capable of performing NFC communication.

[0036] In the fingerprint authentication system shown in Fig. 1, when the fingerprint authentication unit 3 "authenticates that the fingerprint is the same", it notifies the contactless IC card reader 10 by making the IDm1 data readable. As a variation, it may be possible to make other data or a combination of IDm and other data readable. Various methods have been proposed and are in practical use as authentication methods for this notification method, and the method may be selected taking into consideration the required level of security.

[0037] The notification method can also be realized by carrying out the following process. That is, when the fingerprint authentication unit 3 authenticates the same fingerprint by simply sending a predetermined command from the non-contact IC card reader 10, the first NFC chip 6 transmits predetermined data, and the non-contact IC card reader 10 receives this data, thereby realizing the notification method. However, even if the fingerprint authentication unit 3 does not authenticate the same fingerprint, there is a risk that security will be breached by sending the same data as the predetermined data to the non-contact IC card reader 9 by some other means, as if the fingerprint has been "authenticated as the same fingerprint." It is necessary to be careful of this misuse.

[0038] Regarding this misuse, for example, when another smartphone-compatible NFC card 1 with fingerprint authentication function in which a different fingerprint is registered is linked to the smartphone 9, in order to prevent the smartphone 9 from operating as if the fingerprint has been authenticated, it is preferable to have unique data on the smartphone-compatible NFC card 1 with fingerprint authentication function. It is also preferable to adopt a countermeasure such as making it a prerequisite for fingerprint authentication to be successful that this unique data matches the data registered on the smartphone 9.

[0039] In the fingerprint authentication system shown in FIG. 1, the notification method is realized by transmitting IDm1 data of the first NFC chip 6. The Felica chip has a unique ID number called "IDm" that is recorded when the Felica chip is manufactured. The IDm data cannot be rewritten. This IDm is strictly managed by the manufacturer. Felica chips with the same IDm data are unique in the world and are strictly managed so that no other chips exist, so it is difficult to break security without fingerprint authentication as described above. In other words, it is practically difficult to break security by using some kind of fraudulent means to make the smartphone 9 recognize that "fingerprint authentication was successful."

[0040] IDm is used for authentication in general security cards, and no major problems have arisen to date. However, some say that since IDm's communication methods are disclosed, it is possible to forge it. Another problem with general FeliCa cards is that the IDm data can easily be read by skimming. The fingerprint authentication system shown in Figure 1 controls so that IDm1 data can only be read if the fingerprint authentication unit 3 recognizes the same fingerprint. This makes skimming impossible unless the fingerprint is authenticated as the same. This can significantly reduce the risk of skimming.

[0041] As countermeasures against IDm forgery of FeliCa chips, methods such as MAC authentication using a secret key for FeliCa Lite-S chips and using a secure area for FeliCa Standard chips have been proposed. These methods can be applied as appropriate to the notification method of the fingerprint authentication system shown in Figure 1.

[0042] An example of a control method in which the smartphone 9 controls the electronic circuit built into the smartphone-compatible NFC card 1 with fingerprint authentication function in the fingerprint authentication system shown in FIG. 1 will be described with reference to the flowchart shown in FIG.

[0043] When the application software installed on the smartphone 9 is started, in the first step S1, a message "Please touch the fingerprint sensor" is displayed on the display of the smartphone 9 in Fig. 1, and a built-in timer is started (S2). In this software, a command to turn on polling is sent to the contactless IC card reader 10 (S3), and the contactless IC card reader 10 starts polling and supplies power to the first coil 5.

[0044] The first coil 5 that has received the power supplies power to the fingerprint sensor 2, the fingerprint authentication unit 3, the memory 4, etc. This starts the fingerprint authentication. In the next step S4, the software proceeds to step S5 until the timer has counted down to 10 seconds, and proceeds to step S9 when 10 seconds have elapsed.

[0045] In step S5, this software transmits a command to read the IDm data to the contactless IC card reader 10. The contactless IC card reader 10 responds to this software with information on whether reading the IDm data was successful or unsuccessful. If reading the IDm fails, or if the IDm data read in the next step S6 matches the IDm2 data of the second NFC chip 8, the process returns to step S3 and polling is repeated.

[0046] An important thing to note when polling is repeated is that the fingerprint authentication unit 3 requires a calculation time of 0.5 to 2 seconds to complete fingerprint authentication. During this loop period, the first coil 5 must always be in a state where it can receive power continuously. For this reason, it is necessary to set the time for power supply with one polling command to the non-contact IC card reader 10 to be somewhat longer using the command parameters, etc., so that the first coil 5 can always be in a state where it can receive power continuously.

[0047] In step S6, if the read IDm data does not match the IDm2 data of the second NFC chip 8, the process proceeds to step S7. The IDm1 data of the first NFC chip 6 can be read by the non-contact IC card reader 10 only if the fingerprint authentication unit 3 has authenticated the same fingerprint. Therefore, if the IDm data read in step S7 matches the IDm1 data registered in advance in the smartphone 9, the system in the smartphone 9 is notified that "fingerprint authentication was successful with the smartphone-compatible NFC card 1 with fingerprint authentication function" (S8).

[0048] On the other hand, if the IDm data does not match in step S7, it is assumed that the contactless IC card reader 10 has read the IDm data of another FeliCa card. As a result, the system in the smartphone 9 is notified that "fingerprint authentication has failed in the smartphone-compatible NFC card 1 with fingerprint authentication function" (S9). After notifying the system of the result of the fingerprint authentication, polling is turned off (S10) and the application software is terminated.

[0049] When the system in the smartphone 9 recognizes that fingerprint authentication has been successful with the smartphone-compatible NFC card 1 with fingerprint authentication function, it unlocks the smartphone or permits connection to a specific network. In other words, according to the fingerprint authentication system shown in Fig. 1, the smartphone 9 can use the smartphone-compatible NFC card 1 with fingerprint authentication function as a fingerprint authentication device.

[0050] The inventors of the present application created application software conforming to the flowchart shown in FIG. 2, which is compatible with the iPhone of Apple Inc., and verified the actual operation of an NFC card 1 with a smartphone-compatible fingerprint authentication function. Recent iPhones have built-in contactless IC card readers. For the iPhone, application software was created using CoreNFC, an NFC-standard communications framework, to be compatible with iOS13 and later OS. Then, using the contactless IC card reader built into the iPhone, the operation of an NFC-standard card, such as a general FeliCa card, was verified.

[0051] Using CoreNFC, we created application software for iPhone according to the flow chart shown in Figure 2 and verified its operation, and confirmed that it was possible to read IDm and UID of NFC-compliant cards such as general FeliCa cards and MyFair cards. However, for the fingerprint authentication system shown in Figure 1, we found a problem that continuous power supply was not possible and fingerprint authentication and IDm1 reading were not possible when the second NFC chip 8 was always kept inactive, i.e., in the same configuration as commercially available NFC cards with fingerprint authentication functions made for security purposes.

[0052] Even if the second NFC chip 8 is always held inactive, fingerprint authentication is possible as long as it is continuously powered by a contactless IC card reader. If fingerprint authentication is successful, it will function as a FeliCa card and IDm1 can be read. This is the same operation as commercially available NFC cards with fingerprint authentication functions designed for security purposes.

[0053] FIG. 3 shows the power supply state to the first coil 5 when the application software for iPhone based on the flow chart shown in FIG. 2 is started in the fingerprint authentication system shown in FIG. 1 with the second NFC chip 8 always held inactive. FIG. 3 is a timing chart of the first example. After examining the above-mentioned problem, that is, the problem of not being able to supply power continuously, the inventors of the present application found that the cause is that the period for supplying power at one time by the polling command is short in the initial setting. In response to this problem, even if the timeSlot value of the parameters such as the CoreNFC Polling command was changed to lengthen the period for one polling, the actual power supply period did not change. For this reason, as shown in FIG. 3, power is supplied to the first coil 5 for a short time only at a fixed cycle. Therefore, it was found that the fingerprint authentication system shown in FIG. 1 on the iPhone cannot be kept in a continuous power supply state by the application software alone in a state where the second NFC chip 8 is always held inactive.

[0054] It was confirmed that when an NFC-compliant card such as a general FeliCa card or MyFair card is brought close to the contactless IC card reader 10 built into the iPhone, that is, when NFC communication is being performed, the change in the timeSlot value is effective, the power supply period can be adjusted, and it is possible to enter a continuous power supply state. However, in the fingerprint authentication system shown in FIG. 1, when the second NFC chip 8 is always kept inactive, the first NFC chip 6 enters a state in which NFC communication is possible only after fingerprint authentication is successful. And fingerprint authentication is not completed unless the power supply time can be extended. Therefore, the change in the timeSlot value is not effective, and it is not possible to enter a continuous power supply state.

[0055] In this application software, when the fingerprint authentication system shown in FIG. 1 is operated and the second NFC chip 8 is always held inactive, it cannot be continuously powered. When an NFC-compliant card such as a general FeliCa card or MyFair card is brought close to the built-in contactless IC card reader 10, NFC communication is performed and the change in the timeSlot value is valid. Then, the actual polling period becomes longer and power is continuously supplied. By putting the system into a continuous power supply state, it was confirmed that the fingerprint authentication system shown in FIG. 1 can perform fingerprint authentication, and the first NFC chip 6 can operate after fingerprint authentication is successful.

[0056] However, when the card brought close to the non-contact IC card reader 10 to change the timeSlot value is a MyFair card, even after the fingerprint authentication is successful in the fingerprint authentication system shown in Fig. 1, the built-in non-contact IC card reader 10 reads the UID, which is the unique data of the MyFair card, and is unable to read the IDm1 data of the first NFC chip 6, which is a FeliCa chip. The inventor of this application believes that this is because the built-in non-contact IC card reader 10 first performs NFC communication with the MyFair card and then tries to maintain communication with the MyFair card, preventing communication with the first NFC chip 6. In this state, if the MyFair card is removed from the non-contact IC card reader 10 to forcibly stop the NFC communication with the MyFair card, it becomes possible to read the IDm1 data of the first NFC chip 6.

[0057] To solve this problem, it is necessary to have the built-in contactless IC card reader 10 recognize the NFC chip after power supply to the first coil 5 begins so that the built-in contactless IC card reader 10 can be in a continuous power supply state, so that the change in the timeSlot value becomes effective, and to have the contactless IC card reader 10 actually read the IDm1 of the first NFC chip 6 in the continuous power supply state.

[0058] In the NFC communication standard, the communication sequence between a contactless IC card reader and an NFC card consists of, first, an "initial response" that sets up a communication path between the contactless IC card reader and the target NFC card, and, second, an "active state" that exchanges information according to the application.

[0059] First, when power supply from the contactless IC card reader begins in response to the initial response, the NFC card enters a state in which it waits for a request (request command) from the contactless IC card reader to set up a communication path. Next, the contactless IC card reader sends a request command, and the NFC card returns a response. This recognizes the NFC card present in the communication area of ​​the contactless IC card reader. The contactless IC card reader then exchanges parameters with the recognized NFC card, and mutually confirms conditions such as communication speed. After this, the state transitions from the initial response to the active state. In the active state, the NFC card recognized in the initial response is selected, and NFC communication is performed by repeating responses from the NFC card to commands from the contactless IC card reader.

[0060] There are various types of NFC cards, such as Type A MyFair cards, Type B Japanese driver's licenses, and Type F FeliCa cards, and the method of handling the case where multiple NFC cards of the same type are simultaneously present in the initial response is determined for each type. When multiple NFC type cards are present, only cards of the specified type can be recognized by specifying the type of card to be read. When multiple types are specified, cards of the specified types can be recognized. However, there are restrictions not specified in the NFC communication standards, such as when a MyFair card and a FeliCa card are recognized at the same time, the UID of the MyFair card is read with priority over the IDm of the FeliCa card.

[0061] Type A cards such as the MyFare Card use a method in which (i) if multiple MyFare Cards are recognized during the initial response, the UIDs of all recognized MyFare Cards are read using a method called the bit collision method, then (ii) one of the UIDs read is designated by the contactless IC card reader, and (iii) one of the MyFare Cards with a matching UID responds, thereby selecting one from the multiple MyFare Cards. Therefore, a MyFare Card that does not respond during the initial response cannot be selected.

[0062] When multiple Felica chips exist, (i) when the IDm of the Felica card is known, IDm is specified and the Felica card with the matching IDm responds, or (ii) when the system codes of multiple Felica cards are different, the system code can be specified to read the IDm data of the corresponding Felica card even when the cards are stacked. In order to change the timeSlot value at the time of initial response, if the Felica card brought close to the contactless IC card reader 10 is a Felica card with a different system code from that of the first NFC chip 6 included in the fingerprint authentication system shown in FIG. 1, even if the Felica card is in an operating state after the fingerprint authentication is successful, it was confirmed that the built-in contactless IC card reader 10 can read the IDm1 data of the first NFC chip 6 by specifying the system code of the first NFC chip 6 on the side of the smartphone-compatible NFC card 1 with fingerprint authentication function. Since the Felica card that responded initially has a different system code from the first NFC chip 6, its IDm cannot be read, but it was confirmed that it can be continuously powered.

[0063] In the contactless IC card reader 10 built into the iPhone, if any NFC chip is recognized in the initial response, the change in the timeSlot value becomes valid. However, in order to maintain a continuous power supply state and, after fingerprint authentication is successful, to enable the first NFC chip 6 having an NFC communication function on the side of the smartphone-compatible NFC card with fingerprint authentication function 1 to notify the contactless IC card reader 10 that fingerprint authentication has been successful, it is necessary to effectively combine the control timing of the NFC chip recognized in the initial response, the type of NFC chip, and the type of the first NFC chip 6 having an NFC communication function on the side of the smartphone-compatible NFC card with fingerprint authentication function 1.

[0064] FIG. 4 shows the power supply state to the first coil 5 when the application software for iPhone based on the flow chart shown in FIG. 2 is started in the fingerprint authentication system shown in FIG. 1. FIG. 4 is a timing chart of the second example. Referring to FIG. 4, apart from the first NFC chip 6 that operates when fingerprint authentication is successful, the second NFC chip 8 and the second coil 7 that are recognized in the initial response to enable the change of the timeSlot value are added to the NFC card 1 with the smartphone-compatible fingerprint authentication function, and when the first coil 5 is supplied with power, the second coil 7 is also supplied with power, and the second NFC chip 8 is made operable for a short time after a short polling period set in the initial setting. As a result, an initial response of NFC communication is made between the built-in non-contact IC card reader 10 and the second NFC chip 8 within the short polling period set in the initial setting, the change of the timeSlot value is enabled, the actual polling period is lengthened, and the state in which continuous power supply is performed is achieved. Even if the operation of the second NFC chip 8 is stopped after the continuous power supply state is achieved, the continuous power supply state is maintained for a certain period of time. Since fingerprint authentication takes at least 0.5 to 1 second, the second NFC chip 3 may be put into an operable state by starting power supply, and then stopped operating in about 0.3 seconds.

[0065] 4, the second NFC chip 8 is activated a little after the first coil 5 is powered, but they may be activated at the same time. The delay time is provided to delay the order of recognition so that the second NFC chip 8 does not interfere with the communication of another NFC card when the smartphone-compatible NFC card 1 with fingerprint authentication function is used overlapping with another NFC card.

[0066] If the second NFC chip is a Felica chip, there is no chip with the same IDm, so if fingerprint authentication is unsuccessful, the IDm that can be read by an external contactless IC card reader will be IDm2 of the second NFC chip 8. Furthermore, if only the Felica chip is recognized in the initial response, then, not only when the system codes of the two Felica chips are different, but also when there is only one Felica chip operating simultaneously, NFC communication is possible after transition to the active state even if the system code of the second NFC chip 8 is the same as the system code of the first NFC chip 6, and the IDm of the Felica chip operating at that time can be read.

[0067] Therefore, even if two low-cost FeliCa Lite-S chips are mounted in the NFC card 1 with a smartphone-compatible fingerprint authentication function, if they are controlled not to operate simultaneously, the IDm2 of the second NFC chip 8 can be read immediately after the start of power supply to the first coil 5, and the IDm1 of the first NFC chip 6 can be read after the fingerprint authentication is successful. If this is actively utilized, it is possible to perform fingerprint authentication and use IDm1 (first mode) for applications with strict security, and to use IDm2 easily without fingerprint authentication (second mode) for applications with less strict security, improving convenience. The second mode can be used in a state where fingerprint authentication is not successful. For example, the second mode can be used reliably by preventing a finger from touching the fingerprint sensor.

[0068] Also, in the timing chart of Fig. 4, there is a period in which all NFC chips stop after the second NFC chip is made operable for a short period of time. During this period, the card information recognized in the initial response is initialized. Even if all NFC chips stop, the continuous power supply state is maintained for a certain period of time, so fingerprint authentication is performed and the first NFC chip becomes operational after the fingerprint authentication is successful. Then, the first NFC chip is recognized in the next initial response, so the first NFC chip can notify the non-contact IC card reader 10 without any problems that fingerprint authentication was successful.

[0069] As a result, in the timing chart of Figure 4, even if the second NFC chip is a MyFair chip, the MyFair chip will be in an operable state for a short period of time, and after the initial response enters a continuous power supply state, all NFC chips including the MyFair chip will stop, and after successful fingerprint authentication, only the first NFC chip 6 will be in an operable state, so that the first FeliCa chip 6 will make an initial response and be able to read IDm1.

[0070] In other words, the timing chart in Figure 4 allows for a wider range of options for the first and second NFC chips. In principle, there are no restrictions on the combination of the two NFC chips, but it is necessary to verify each model of smartphone to determine which options will actually work. It is also necessary to be aware that the short time the MyFair chip is in an operational state will not cause problems with NFC communication when making electronic money payments using the built-in contactless IC card reader with other application software.

[0071] Specifically, the timing chart in Figure 4 shows that the combination of the MyFair chip and the FeliCa chip allows for continuous power supply, fingerprint authentication, and fingerprint authentication notification without any problems. In this case, the second NFC chip only needs to be able to make an initial response, and the type of the first NFC chip determines whether it can be used with electronic locks, access control systems, and attendance management systems. In Japan, systems that can use the FeliCa chip are the norm, and there are systems that can use the MyFair chip in areas where inexpensive cards are required, such as hotel door keys. Overseas, the MyFair chip is by far the mainstream.

[0072] Therefore, it was necessary to prepare two types of NFC cards with fingerprint authentication for security purposes: FeliCa type and MyFair type. Since NFC cards with fingerprint authentication function for smartphones can be made with both MyFair and FeliCa chips, if it is possible to set for each card whether the first NFC chip is MyFair or FeliCa, it will be unnecessary to manufacture different cards for Japan and overseas. In other words, if it is possible to change the NFC chip that the fingerprint authentication unit 3 enables when power supply starts and the NFC chip that enables it after fingerprint authentication, and if it is possible to set for each card to operate by switching between the first NFC chip and the second NFC chip, it will be possible to mass-produce one type of card, which will reduce costs and make inventory management easier.

[0073] FIG. 5 shows the power supply state to the first coil 5 when starting up the iPhone application software based on the flowchart shown in FIG. 2 in the fingerprint authentication system shown in FIG. 1. FIG. 5 is a timing chart of the third example. As explained with reference to the timing chart of the second example of FIG. 4, the second NFC chip 8 recognized in the initial response is added to the NFC card 1 with the smartphone-compatible fingerprint authentication function, and the second NFC chip 8 is activated a little later when the first coil 5 is powered. In the timing chart of the third example of FIG. 5, the second NFC chip 8 is activated until the fingerprint authentication is successful. This is done to delay the timing of stopping the second NFC chip 8 compared to the timing of the second example of FIG. 4 described above.

[0074] In the timing chart of the third example in FIG. 5, the first NFC chip 6 is put into an operating state at the same time as the second NFC chip 8 stops operating, and there is no period in which all NFC chips are stopped as in the timing chart of the second example in FIG. 4. If it is desired to provide a period in which the second NFC chip 8 continues to operate when fingerprint authentication is not performed and only the first NFC chip 6 operates when fingerprint authentication is successful, and all NFC chips are stopped, it is also possible to control the second NFC chip 8 to stop operating when it detects that a finger has touched the fingerprint sensor 2, so that all NFC chips are stopped for, for example, 0.5 seconds or more from the time the finger touches the fingerprint sensor 2 until fingerprint authentication is successful. It is preferable to configure the second NFC chip 8 so that the parameters of the timing and conditions under which it operates, including the parameter of whether or not a finger is touching the fingerprint sensor after the second NFC chip 8 is put into an operating state from the start of power supply, can be changed according to the smartphone to be used.

[0075] FIG. 6 shows the power supply state when the iPhone application software based on the flowchart shown in FIG. 2 is started in the fingerprint authentication system shown in FIG. 1. FIG. 6 is a timing chart of the fourth example. As in the timing chart of the second example of FIG. 4, a second NFC chip 8 and a second coil 7 that are recognized in the initial response are added to the NFC card 1 with a smartphone-compatible fingerprint authentication function. The second NFC chip 8 is connected to the second coil 7, and is configured to operate when the second coil 7 is supplied with power. When the first coil 5 is supplied with power, the second coil 7 is also supplied with power at the same time, so the second NFC chip 8 is made to operate and maintains the operating state until the power supply to the first coil 5 is stopped.

[0076] 6, after the fingerprint authentication is successful, not only the first NFC chip 6 but also the second NFC chip 8 enters an operating state at the same time. Therefore, even if the second NFC chip 8 that has made an initial response is in operation, it is necessary to select a type of FeliCa chip that can read the IDm1 of the first NFC chip 6 that has not made an initial response.

[0077] As mentioned above, if only one Felica chip responds at the time of the initial response, Felica can read multiple Felica chips thereafter. To read multiple Felica chips, you can specify IDm or a system code, and the corresponding Felica chip will respond. However, CoreNFC does not have a way to specify IDm. Therefore, you must specify a system code to read the corresponding Felica chip. In this case, if multiple system codes are specified, the corresponding Felica chips can be read simultaneously.

[0078] If there are multiple FeliCa chips with the same system code, they cannot be read simultaneously, so the second NFC chip 8 should be a FeliCa chip with a system code different from that of the first NFC chip 6.

[0079] As in the fourth example timing chart of Fig. 6, when the second NFC chip 8 and the first NFC chip 6 are two Felica chips with different system codes, and the second NFC chip 8 is continuously in an operating state during the period of power supply to the first coil 5 regardless of fingerprint authentication, the second NFC chip 8 does not need to synchronize timing with the fingerprint authentication unit 3. Therefore, in the fingerprint authentication system shown in Fig. 1, it is possible to add a second coil other than the first coil 5 exclusively for the second NFC chip 8. It is possible to configure the same function as a general Felica card function and to make it an independent circuit board without being connected by wire to other circuits in the smartphone-compatible NFC card 1 with fingerprint authentication function.

[0080] The Felica card or equivalent functions, which correspond to the second NFC chip 8 and the second coil, can be independently configured in the form of a sticker or flexible circuit board module, and attached to the surface of the smartphone-compatible NFC card 1 with fingerprint authentication function. In addition, by combining a flexible circuit board module with functions equivalent to a Felica card with the inlay of an existing NFC card with fingerprint authentication function and laminating it into a card shape, it is possible to shorten the design time and manufacture the card. It has been confirmed that this configuration works without any problems.

[0081] As described above, according to the examples described based on the timing charts shown in Figures 4, 5, and 6, even in a smartphone such as an iPhone that cannot make the power supply from the contactless IC card reader 10 built into the smartphone 9 continuous by application software alone, (i) a fingerprint authentication function is installed in the smartphone-compatible NFC card 1 with fingerprint authentication function, (ii) fingerprint authentication is started by receiving power from the contactless IC card reader 10 built into the smartphone 9, (iii) power supply is made continuous by recognizing the second NFC chip 8 in the initial response, and (iv) when fingerprint authentication is successful, the contactless IC card reader 10 receives a fingerprint authentication notification from the first NFC chip 6, and can inform the smartphone 9 that "the fingerprint has been authenticated as the same fingerprint." Thus, a fingerprint authentication function can be substantially added to the smartphone 9.

[0082] The inventors of this application tested the smartphone-compatible NFC card 1 with fingerprint authentication function that works with iPhones based on the present invention in a system in which a contactless IC card reader is connected to a personal computer. They confirmed that even in systems in which a continuous power supply state cannot be achieved unless the software that controls the contactless IC card reader installed in the personal computer is modified, and in which the existing fingerprint authentication card does not work, some systems can be made to enter a continuous power supply state by holding up the smartphone-compatible NFC card 1 with fingerprint authentication function without modifying the software, and the fingerprint authentication function can be used.

[0083] In a system in which a contactless IC card reader is connected to a personal computer, when using an NFC card 1 with a smartphone-compatible fingerprint authentication function, it is necessary to register the unique data such as IDm1 read by the contactless IC card reader in the system before use. For this purpose, for example, when fingerprint information is not registered in the NFC card with a smartphone-compatible fingerprint authentication function, the first NFC chip (first NFC chip 6) operates when power is supplied wirelessly, and the second NFC chip (second NFC chip 8) is controlled not to operate, so that the unique data such as IDm1 can be easily registered in the system. At that time, even if the system software cannot control the contactless IC card reader connected to the personal computer to a continuous power supply state, the unique data such as IDm1 can be read in a short time, so that continuous power supply is not necessary and it becomes possible to register the unique data such as IDm1 in the system without changing the software.

[0084] In addition, in some systems where a contactless IC card reader is connected to a personal computer, if the FeliCa card is removed from the contactless IC card reader, the system determines that the card owner has left the computer and locks the computer. In contrast to such systems, in the smartphone-compatible NFC card 1 with fingerprint authentication function of the present invention, it is not preferable from the viewpoint of security that the first NFC chip 6 continues to operate after fingerprint authentication. For this reason, it is preferable that the first NFC chip 6 stops operating after a certain period of time after fingerprint authentication, and the second NFC chip 8 continues to operate instead, and IDm2 is used to determine whether the user has left the computer. It is preferable that the settings of the two NFC chips after a certain period of time has passed after the fingerprint authentication is successful can be changed for each card according to the system used. In the case of the fourth example timing chart of FIG. 6, the second NFC chip 8 is always in an operable state during power supply, so it can be used as is to determine whether the user has left the computer.

[0085] FIG. 7 is an explanatory diagram of a case where an NFC card 1 with a smartphone-compatible fingerprint authentication function according to an embodiment of the present invention is attached to a smartphone 9 using, for example, double-sided tape. In FIG. 7, the same elements as those shown in FIG. 1 are given the same reference symbols. Reference symbol CL indicates a camera lens, and the camera lens CL is located on the back surface of the smartphone 9. Here, "back surface" means the surface opposite to the surface on which the display screen of the smartphone 9 is provided. Referring to FIG. 7, inside the NFC card 1 with a fingerprint authentication function, a first coil 5 is formed by a printed pattern of copper foil, and in addition to the fingerprint sensor 2, electronic circuit components such as the fingerprint authentication unit 3, memory 4, first NFC chip 6, and second NFC chip 8 shown in FIG. 1 are mounted.

[0086] The size of smartphone-compatible NFC card 1 with fingerprint authentication function is usually made to match the dimensions of a standardized credit card, but in Fig. 7, it is miniaturized into a long and thin shape so that the camera lens CL can be used when attached to the back of smartphone 9. Smartphone-compatible NFC card 1 with fingerprint authentication function can be manufactured with the same thickness of 0.76 mm as a credit card, and by attaching it to a smartphone as shown in Fig. 7, it can be used in an integrated state with almost no increase in the thickness of the smartphone, providing the same functionality and usability as a fingerprint authentication device built into the smartphone.

[0087] In the fingerprint authentication system shown in Fig. 1, when power supply from the non-contact IC card reader 10 starts, as in the second example timing chart of Fig. 4, the first NFC chip 6 that performs NFC communication is controlled not to operate until the fingerprint authentication unit 3 authenticates the same fingerprint. The first NFC chip 6 that performs NFC communication is also controlled not to operate when no finger touches the fingerprint sensor 2. The second NFC chip 8 is controlled to operate only for a short time when power supply from the non-contact IC card reader 10 starts.

[0088] As a result, when NFC card 1 with smartphone-compatible fingerprint authentication function is attached to smartphone 9 as shown in Figure 7, not only can the fingerprint authentication function be used on the smartphone, but also (i) when another NFC card is read with non-contact IC card reader 10 built into smartphone 9, or (ii) when non-contact IC card reader 10 built into smartphone 9 performs NFC communication with various external devices such as for paying electronic money, even if power is supplied to first coil 5 in NFC card 1 with smartphone-compatible fingerprint authentication function.

[0089] In particular, if the second NFC chip 8 is a FeliCa chip, it will not interfere with reading the MyFare card. In order to avoid any problems when the contactless IC card reader 10 built into the smartphone 9 uses the FeliCa Standard system code for electronic money payments, etc., a FeliCa chip with a different system code, specifically a FeliCa Lite-S chip, can be used as the second NFC chip 8. In this case, reading is hindered when the second NFC chip and another FeliCa Lite-S card are in operation at the same time, but since the second NFC chip 8 only operates for a short time when power supply from the contactless IC card reader 10 begins, there is essentially no problem.

[0090] When the non-contact IC card reader 10 built into the smartphone 9 wishes to perform NFC communication with various external devices, such as for electronic money payments, immediately after successful fingerprint authentication, the first NFC chip 6 can be controlled not to operate by temporarily stopping the power supply from the non-contact IC card reader 10 after the smartphone 9 recognizes that fingerprint authentication has been successful.

[0091] The back of a current smartphone is occupied by the built-in battery and built-in camera, and the built-in contactless card reader 9 is often housed in a narrow area located next to the camera lens CL. This positional relationship is almost the same for most smartphones currently on the market, and the card shape in Fig. 7 can be designed to be applicable to multiple smartphone models of different sizes.

[0092] Although the source code of the application software for the operation of the fingerprint authentication system shown in Fig. 1 differs depending on the smartphone's OS, the fingerprint authentication system is OS-independent and the same smartphone-compatible NFC card 1 with fingerprint authentication function can be used on smartphones with different OSs. Therefore, by designing a card shape that can be attached to various smartphones, it is possible to mass-produce smartphone-compatible NFC cards 1 with fingerprint authentication function of the same shape and reduce costs. In addition, since the cards are manufactured on a line that produces credit card-sized contactless IC cards, card manufacturing costs can be reduced by making the card shape such that two or more cards can be taken within the credit card size.

[0093] Figures 8 and 9 are cross-sectional views for explaining the fingerprint authentication system of Figure 4. In Figures 8 and 9, the same elements as those shown in Figure 4 are given the same reference numerals. Reference numeral 12 shown in Figures 8 and 9 is a smartphone case that is attached to a smartphone 9. Reference numeral 13 is an LED that is mounted on the NFC card 1 with fingerprint authentication function and constitutes a display unit that displays the power supply status of the NFC card with fingerprint authentication function and the success or failure of fingerprint authentication, etc.

[0094] 8 shows a state in which NFC card 1 with fingerprint authentication function is accessed near non-contact IC card reader 6. When power supply from non-contact IC card reader 6 starts in this state, second NFC chip 8 in authentication circuit board 1 is activated, and second NFC chip 8 is recognized by non-contact IC card reader 6 in the initial response, and then power is continuously supplied to NFC card 1 with fingerprint authentication function, enabling fingerprint authentication.

[0095] 9, in the illustrated embodiment, a mechanism for holding the NFC card 1 with a fingerprint authentication function is added to the smartphone case 12. By adding this card holding mechanism to the smartphone case 12, the NFC card 1 with a fingerprint authentication function can be stored in the smartphone case 12 when not in use. When performing fingerprint authentication, the NFC card 1 with a fingerprint authentication function is pulled out from the smartphone case 12, and fingerprint authentication is performed in the state illustrated in FIG. 9. In both cases of FIG. 8 and FIG. 9, the fingerprint sensor 9 is located on the same side as the display screen of the smartphone 9, so that fingerprint authentication can be performed reliably by touching the fingerprint sensor 9 with a finger 14 while actually checking the position of the fingerprint sensor 9 with one's eyes. In addition, the LED 13 on the NFC card 1 with a fingerprint authentication function makes it possible to perform fingerprint authentication while checking the power supply status and the success or failure of fingerprint authentication. The usage as illustrated in FIG. 9 can also be achieved by attaching a card holder for holding a commercially available credit card-sized card to the smartphone case 12 of FIG. 8.

[0096] 8 and 9, by using multiple NFC cards 1 with fingerprint authentication function, it is possible to perform fingerprint authentication with separate cards for corporate and personal use, thereby achieving higher security. Also, with one NFC card 1 with fingerprint authentication function, it is possible to use the fingerprint authentication function not only on smartphone 9 but also on other terminals, which increases convenience.

[0097] The fingerprint authentication system illustrated in FIG. 1, FIG. 7, FIG. 8, and FIG. 9 can provide the same usability as a fingerprint authentication device built into a smartphone. In addition, security can be ensured against attacks such as SIM swap attacks, in which a criminal registers his / her own biometric information in a new smartphone to which the criminal has transferred his / her phone number, thereby invalidating the face authentication and fingerprint authentication built into the smartphone. That is, a criminal cannot obtain an NFC card 1 with a fingerprint authentication function with a registered fingerprint only by a SIM swap attack. Even if a criminal obtains a new NFC card 1 with a fingerprint authentication function with a fingerprint not registered and registers his / her own fingerprint, the unique data in the NFC card 1 with a fingerprint authentication function is different, so that even if a SIM swap attack is performed, the fingerprint authentication is not recognized as successful. Even if a criminal can obtain an NFC card 1 with a fingerprint authentication function with a registered fingerprint, fingerprint authentication will not be successful with the criminal's fingerprint. In this way, it can be said that the fingerprint authentication system of the present invention is a fingerprint authentication device that is effective against SIM swap attacks. The fingerprint authentication system of the present invention can provide higher security than a fingerprint authentication device built into a smartphone.

[0098] In the embodiments of the present invention, a Felica chip installed in a commercially available Felica card is described as being used as the first NFC chip 6 and the second NFC chip 8, but it would be easy for a person skilled in the art to customize the Felica chip to add a mode in which IDm cannot be read during the initial response and to allow reading of IDm2 of the second NFC chip 8 upon detecting that a finger is touching the fingerprint sensor, thereby making it difficult to skim IDm2 of the second NFC chip 8, or to reduce costs by integrating the first NFC chip 6 and the second NFC chip 8 onto a single silicon chip and sharing the wireless communication parts, etc., to reduce the chip size. [Explanation of symbols]

[0099] 1. NFC card with fingerprint authentication function for smartphones Fp Fingerprint authentication method 2 Fingerprint sensor 3 Fingerprint authentication section 4. Memory 5 First coil 6 The first NFC chip 7 Second coil 8. The Second NFC Chip 9. Smartphones 10. Contactless IC card reader 11 Fingerprint of registered user 12 Smartphone cases 13 LED

Claims

1. An NFC card with a fingerprint authentication function for smartphones, capable of recognizing successful fingerprint authentication on a smartphone having a built-in non-contact IC card reader, A fingerprint sensor; A fingerprint authentication unit; A memory for storing fingerprint data for matching; A first coil that receives power from the non-contact IC card reader; a fingerprint authentication means including a first NFC chip having a function of performing NFC communication with the non-contact IC card reader; The fingerprint authentication means includes: a fingerprint data reading function that starts reading fingerprint data using the fingerprint sensor when the first coil receives power from the non-contact IC card reader; a fingerprint data matching function for matching the read fingerprint data with the matching fingerprint data stored in the memory by the fingerprint authentication unit; a fingerprint authentication notification function for notifying the non-contact IC card reader that the fingerprints have been authenticated as the same fingerprint by the fingerprint authentication unit, by allowing the first NFC chip to perform the NFC communication only when the fingerprint authentication unit authenticates the fingerprints as the same fingerprint, the fingerprint sensor, the fingerprint authentication unit, the memory, and the first NFC chip operate only with power received by the first coil; the smartphone is a model in which continuous power supply from the non-contact IC card reader to the first coil cannot be performed by application software installed thereon alone, a second NFC chip separate from the first NFC chip; A smartphone-compatible NFC card with fingerprint authentication function, characterized in that when the first coil receives power from the non-contact IC card reader, the second NFC chip is recognized in the initial response to the NFC communication, thereby continuously supplying power from the non-contact IC card reader to the first coil.

2. An NFC card with a fingerprint authentication function for smartphones, capable of recognizing successful fingerprint authentication on a smartphone having a built-in non-contact IC card reader, A fingerprint sensor; A fingerprint authentication unit; A memory for storing fingerprint data for matching; A first coil that receives power from the non-contact IC card reader; a fingerprint authentication means including a first NFC chip having a function of performing NFC communication with the non-contact IC card reader; The fingerprint authentication means includes: a fingerprint data reading function that starts reading fingerprint data using the fingerprint sensor when the first coil receives power from the non-contact IC card reader; a fingerprint data matching function for matching the read fingerprint data with the matching fingerprint data stored in the memory by the fingerprint authentication unit; a fingerprint authentication notification function for notifying the non-contact IC card reader that the fingerprints have been authenticated as the same fingerprint by the fingerprint authentication unit, by allowing the first NFC chip to perform the NFC communication only when the fingerprint authentication unit authenticates the fingerprints as the same fingerprint, the smartphone is a model in which continuous power supply from the non-contact IC card reader to the first coil cannot be performed by application software installed thereon alone, a second NFC chip separate from the first NFC chip; a second coil separate from the first coil; the fingerprint sensor, the fingerprint authentication unit, the memory, and the first NFC chip operate only with power received by the first coil or the second coil; A smartphone-compatible NFC card with fingerprint authentication function, characterized in that when the second coil receives power from the non-contact IC card reader, the second NFC chip is recognized in the initial response to the NFC communication, thereby continuously supplying power from the non-contact IC card reader to the first coil.

3. The NFC card with smartphone-compatible fingerprint authentication function described in claim 1 or 2, characterized in that a fingerprint authentication notification that notifies that fingerprint authentication is successful when the fingerprint authentication unit recognizes the same fingerprint is sent to the non-contact IC card reader via NFC communication using data using unique data stored in the first NFC chip.

4. The smartphone-compatible NFC card with fingerprint authentication function described in claim 3, characterized in that when the smartphone compares data using the unique data transmitted from the first NFC chip to the non-contact IC card reader via NFC communication with data previously registered in the smartphone and the data matches, the smartphone recognizes that the fingerprint authentication unit has authenticated the fingerprint as the same.

5. 3. The smartphone-compatible NFC card with fingerprint authentication function according to claim 1, wherein the first NFC chip and the second NFC chip are FeliCa chips.

6. The smartphone-compatible NFC card with fingerprint authentication function according to claim 1 or 2, characterized in that the first NFC chip is an NFC chip of any of Type A, Type B, and Type F, the second NFC chip is an NFC chip of a different type from the first NFC chip, and the first NFC chip and the second NFC chip do not perform the NFC communication simultaneously.

7. The smartphone-compatible NFC card with fingerprint authentication function according to claim 6, characterized in that after the second NFC chip is recognized in an initial response of the NFC communication, a period is provided in which both the first NFC chip and the second NFC chip are stopped during a period in which a continuous power supply state is maintained, and after fingerprint authentication is successful, the first NFC chip is recognized in an initial response and the NFC communication is performed.

8. 7. The smartphone-compatible NFC card with fingerprint authentication function according to claim 6, characterized in that the first NFC chip and the second NFC chip can be set for each card so as to operate interchangeably.

9. 8. The smartphone-compatible NFC card with fingerprint authentication function according to claim 7, characterized in that the first NFC chip and the second NFC chip can be set for each card so as to operate interchangeably.

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