Abstract:
A user authentication method including the steps of: accepting input of biological information; displaying a user authentication screen in which a user name corresponding to the biological information and a part of a password corresponding to the user name are automatically entered; and accepting input for completing the password, the part of which have been automatically entered.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application is based on Japanese Patent Application No. 2005-366176 and No. 2006-043534 respectively filed on Dec. 20, 2005 and Feb. 21, 2006 with Japanese Patent Office, the entire content of which is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to user authentication method, systems provided with user authentication functions, and, apparatuses and computer software provided with user authentication functions.  
         [0004]     2. Background Technology  
         [0005]     For the sake of security, the user is required to input a login ID and a password at the time of logging in a personal computer or an image forming apparatus provided with a hard disk drive in which documents can be accumulated.  
         [0006]     It is tedious to input the login ID and password every time for logging in and in order to eliminate this tedium, a technology has been known (see for example, Patent Document 1) in which the fingerprint authentication data is stored associating it with a login ID and its password, and when the fingerprint authentication is successful, the associated login ID and password are input automatically in the login ID field and the password fields of the login input screen.  
         [0007]     Patent Document 1: Japanese Unexamined Patent Application Publication No. 2003-36247.  
         [0008]     In general, in biometric authentication such as fingerprint authentication, the degree of matching between the feature data that has been input and the registered feature data is computed, and the authentication is done assuming a match to be present for the feature data for which the degree of matching is above a certain value.  
         [0009]     Because of this, it is likely that another person having the similar feature data is wrongly authenticated as the genuine user, and in the method disclosed in Patent Document 1, there is the danger that another person can login using the login ID and password using the genuine user. Further, it is also likely that a plurality of candidates are extracted, and in the method disclosed in Patent Document 1, there is no consideration given to the method of handling when a plurality of candidates have been extracted.  
         [0010]     The present invention has been made with the above problem in view, and the object of the present invention is to provide a user authentication method in which not only the input at the time of logging in becomes simple but also logging in by another person with the login ID and password of the genuine user is suppressed, and it is possible to handle even when a plurality of candidates have been extracted.  
       SUMMARY OF THE INVENTION  
       [0011]     An embodiment reflecting one aspect of the present invention to achieve the above-described object is a user authentication method including the steps of:  
         [0012]     accepting input of biological information;  
         [0013]     displaying a user authentication screen in which a user name corresponding to the biological information and a part of a password corresponding to the user name are automatically entered; and  
         [0014]     accepting input for completing the password, the part of which have been automatically entered.  
         [0015]     An embodiment reflecting another aspect of the present invention is a user authentication method including the steps of:  
         [0016]     accepting input of biological information;  
         [0017]     extracting user data corresponding to the biological information accepted;  
         [0018]     displaying user candidates based on the user data extracted;  
         [0019]     accepting a selection of a specific user among the user candidates displayed;  
         [0020]     displaying a user authentication screen in which a part of a password corresponding to the specific user selected is automatically entered; and  
         [0021]     accepting input for completing the password, the part of which have been automatically entered. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]     These and other objects, advantages and features of the invention will become apparent from the following description thereof taken in conjunction with the accompanying drawings in which:  
         [0023]      FIG. 1  is a block diagram showing the configuration of an image forming apparatus according to the present preferred embodiment;  
         [0024]      FIG. 2  is a control flow diagram related to the login process of the image forming apparatus according to the first preferred embodiment;  
         [0025]      FIG. 3  is an example of the login screen in the first preferred embodiment;  
         [0026]      FIG. 4  is an example of another login screen in the first preferred embodiment;  
         [0027]      FIG. 5  is a control flow diagram related to the login process of the image forming apparatus according to the second preferred embodiment;  
         [0028]      FIG. 6  is an example of the selection input screen when a plurality of candidates are present in second preferred embodiment;  
         [0029]      FIG. 7  is an example of the login screen in the second preferred embodiment; and  
         [0030]      FIG. 8  is an example of another login screen in the second preferred embodiment.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0031]     Apparatus Configuration:  
         [0032]      FIG. 1  is a block diagram showing the configuration of an image forming apparatus  1  according to the first preferred embodiment. The image processing apparatus  1  is configured to have the apparatus main unit  10  and a fingerprint authentication module  30 .  
         [0033]     In the apparatus main unit  10 , at the center is the CPU  11  that executes control of the apparatus main unit  10  according to the programs and is connected mutually via the bus  12  to a ROM  13 , a RAM  14 , a document reading section  15 , an image forming section  16 , a hard disk  17 , a non-volatile memory  18 , an operation section  19 , a display section  20 , and a communication section  21 .  
         [0034]     The ROM  13  stores various types of programs and data and the CPU  11  carries out control of the image forming apparatus  1  using these programs and data.  
         [0035]     The RAM  14  is used as a working storage by the CPU  11  and temporarily stores the programs and data necessary at the time that the CPU  11  carries out the controls.  
         [0036]     The document reading section  15  reads out the original document and generates the image data. The image data so generated is output to the image forming section  16  or the hard disk  17  etc.  
         [0037]     The image forming section  16  carries out image formation on a recording medium based on the image data or document data input from the document reading section  15  or the hard disk  17  etc.  
         [0038]     The hard disk  17  stores the image data input from the document reading section  15  etc.  
         [0039]     The non-volatile memory  18  stores the user login ID and the password for each user while establishing correspondence with a registration number.  
         [0040]     The operation section  19  is operated by the user, and input of the login ID and the password, instruction of image formation, and instruction of storing data in the hard disk  17 , etc., are carried out through this operation section  19 .  
         [0041]     The display section  20  displays screens such as the user login screen that accepts the input of the login ID and the password from the user. The display section  20  includes a touch panel, which may be also used for the operation section  19 .  
         [0042]     The communication section  21  is connected to the fingerprint authentication module  30  to be described later, and transmits the instruction of fingerprint authentication to the fingerprint authentication module  30 .  
         [0043]     The fingerprint authentication module  30 , at the center is the CPU  31  that executes control of the fingerprint authentication module  30  according to the programs, is connected mutually via the bus  32  to a ROM  33 , a RAM  34 , a fingerprint input section  35 , a non-volatile memory  36 , and a communication section  37 .  
         [0044]     The ROM  33  stores various types of programs and data and the CPU  31  carries out control of the fingerprint authentication module  30  using these programs and data.  
         [0045]     The RAM  34  is used as a working storage by the CPU  31  and temporarily stores the programs and data necessary at the time that the CPU  31  carries out the controls.  
         [0046]     The fingerprint input section  35  reads the fingerprint of the user to generate the fingerprint data.  
         [0047]     The non-volatile memory  36  is a memory for storing the generated fingerprint data and stores the fingerprint data while establishing correspondence with a registration number.  
         [0048]     The communication section  37  is connected to the apparatus main unit  10 , and when a fingerprint authentication is successful, it transmits to the apparatus main unit  10  the registration number stored in the non-volatile memory  36  and the degree of matching at the time of authentication.  
       First Embodiment  
       [0049]     Apparatus Control:  
         [0050]      FIG. 2  is a control flow diagram related to the login process of the image forming apparatus according to the first preferred embodiment. This control is carried out by the CPU  11  and CPU  31  executing the processing in cooperation with each other based on the programs stored in ROM  13  and ROM  33 .  
         [0051]     To begin with, the CPU  11  displays in the display section  20  a message, for example, “enter fingerprint” (Step S 1 ). Further, the CPU  11  instructs the CPU  31  to carry out fingerprint authentication (Step S 2 ). Following this instruction, the user places his/her finger in the fingerprint input section  35 .  
         [0052]     Next, the CPU  31  causes the fingerprint input  35  to read the fingerprint of the user and to input the fingerprint data (Step S 3 ).  
         [0053]     Next, the CPU  31  carries out fingerprint authentication by judging whether there exists any fingerprint data to match with the input fingerprint data among the fingerprint data stored in the non-volatile memory  36  (Step S 4 ).  
         [0054]     Next, the CPU  31  transmits the result of authentication (authentication successful or authentication failed) to the apparatus main unit  10  via the communication section  37  (Step S 5 ). If the authentication is successful, it adds to the transmission the registration number corresponding to the matching fingerprint data.  
         [0055]     Next, the CPU  11  judges whether or not the authentication result transmitted from the fingerprint authentication module  30  was successful (Step S 6 ). If authentication is successful (Step S 6 : YES), the CPU  11  reads out the login ID and password corresponding to the added registration number into the RAM  14  from the non-volatile memory  18  (Step S 7 ).  
         [0056]     Next, the CPU  11  displays the login screen which displays the login ID read out in Step S 7  and a part of the password in the display section  20 , and prompts the user to make the completion input of the password (Step S 8 ). For example, as is shown in  FIG. 3 , if the password has eight characters, the leading  6  characters of the password are input automatically and are displayed by six asterisks ‘*’ and the last asterisk ‘*’ is followed by the display of two underscored characters. Following this display, the user makes the completion input of the password from the operation section  19 . In the case of the example shown in  FIG. 3 , the user makes the completion input of the remaining two characters in the part displayed by underscores. By displaying the number of characters to be input using underscores etc., for example, even when a password with a large number of characters is being displayed, the user can immediately recognize which characters are to be input.  
         [0057]     With this, the completion input of the password is made to the CPU  11  (Step S 9 ). In the case of the example shown in  FIG. 3 , the login screen displays two asterisks ‘*’ in addition at the end of the six asterisks ‘*’ displayed earlier.  
         [0058]     By making the user carry out completion input in this manner, even if the collation is successful while wrongly recognizing another person as the genuine user, since that other person cannot login as it is, but has to complete the password, another person logging in with the login ID and password of the genuine user is suppressed.  
         [0059]     In Step S 6 , if the authentication has failed (Step S 6 : NO), the operation proceeds to Step S 10 , and the CPU  11  displays, in the display section  20 , a login screen with the login ID and password fields empty, and prompts the user to enter the login ID and password. Following this instruction, the user enters all the characters of the login ID and password through the operation section  19 .  
         [0060]     For example, if the fingerprint registration condition is bad, and even if the fingerprint authentication has failed in spite of the user being the genuine user, it is possible for the user to login by entering all the characters of the login ID and password.  
         [0061]     In Step S 11 , all the characters of the login ID and password are input to the CPU  11 .  
         [0062]     In Step S 9  or Step S 11 , when the login ID and password are input and logging in is made, the CPU  11  refers to the login IDs and passwords stored in the non-volatile memory  18  to cross-check with the entered login ID and password, and carries out authentication of the entered login ID and password (Step S 12 ). If the authentication is successful (Step S 12 : YES), the CPU  11  outputs the use permission signal to the image forming apparatus (Step S 13 ). If the authentication has failed (Step S 12 : NO), the CPU  11  outputs the use prohibit signal to the image forming apparatus (Step S 14 ).  
         [0063]     In the above manner, according to the present preferred embodiment, at the time of automatically inputting the login ID and password in the login ID field and the password field of the login input screen due to success of biometric authentication, since the entire password is not input automatically but a part of it is made to be entered by the user, not only that the input becomes simple at the time of logging in, but also logging in by another person using the login ID and password of the genuine user is suppressed.  
         [0064]     Although in the present preferred embodiment, the trailing part of the password was made the target of completion input by the user, it can also be the leading part or a middle part of the password. Since it is easy for the user to remember the leading and the trailing parts, it is desirable to use these for the completion input.  
         [0065]     Further, although in the present preferred embodiment, the example of using a number of underscores equivalent to the number of characters of the completion input was explained as an example of the display for prompting for and accepting the completion input from the user, the present invention shall not be construed to be limited to this mode of display, and, for example, the display mode can also be line the one shown in  FIG. 4 . In the example of this figure, considering, for the sake of explanation, that the password has eight characters similar to that shown in  FIG. 3 , in addition to carrying out the automatic input of the leading six characters of the password and displaying them by six asterisks ‘*’, the prompt following the last asterisk character ‘*’ is displayed by a prompt character (for example, by a blinking cursor). In the example of this figure, the user carries out completion input of the remaining characters according to the prompt characters. Here, when even the number of characters in the password differs depending on the user, only the genuine user can know how many characters have to be input following the prompt. In this manner, in the case of the present preferred embodiment, it is possible to make the number of characters of the password have the same kind of meaning as the password itself, and is desirably suitable for achieving security.  
         [0066]     Although in the present preferred embodiment, the fingerprint data was stored in the non-volatile memory  36  of the fingerprint authentication module  30  while establishing correspondence with the registration number, the login ID and password were stored in the non-volatile memory  18  of the apparatus main unit  10  while establishing correspondence with the registration number, and the login ID and password corresponding to the fingerprint were identified by transmitting the registration number from the fingerprint authentication module  30  to the apparatus main unit  10  when the authentication by the fingerprint authentication module  30  was successful, it is also possible to store the login IDs and passwords in the non-volatile memory  36  of the fingerprint authentication module  30 , and to transmit to the apparatus main unit  10  the login ID and the password stored in the non-volatile memory  36  from the fingerprint authentication module  30  when the authentication by the fingerprint authentication module  30  is successful.  
       Second Embodiment  
       [0067]     Apparatus Control:  
         [0068]      FIG. 5  is a control flow diagram related to the login process of the image forming apparatus of  FIG. 1  according to the second preferred embodiment. This control is carried out by the CPU  11  and CPU  31  executing the processing in cooperation with each other based on the programs stored in ROM  13  and ROM  33 .  
         [0069]     To begin with, the CPU  11  displays in the display section  20  a message, for example, “enter fingerprint” (Step S 101 ). Further, the CPU  11  instructs the CPU  31  to carry out fingerprint authentication (Step S 102 ). Following this instruction, the user places his finger in the fingerprint input section  35 .  
         [0070]     Next, the CPU  31  causes the fingerprint input  35  to read the fingerprint of the user and to input the fingerprint data (Step S 103 ).  
         [0071]     Next, the CPU  31  carries out fingerprint authentication by judging whether there exists any fingerprint data to match with the input fingerprint data among the fingerprint data stored in the non-volatile memory  36  (Step S 104 ).  
         [0072]     Next, the CPU  31  transmits the result of authentication (authentication successful or authentication failed) to the apparatus main unit  10  via the communication section  37  (Step S 105 ). If the authentication is successful, it adds to the transmission the registration number corresponding to the matching fingerprint data. When a plurality of candidates of matching fingerprint data are present, the registration number and the degree of matching corresponding to the fingerprint data of each candidate are added and transmitted as the data. By transmitting the data after adding the degree of matching, at the time of displaying later a plurality of candidates in the apparatus main unit  10 , it is possible to display in decreasing order of the degree of matching. In addition, when number of candidates is present, it is also possible to transmit while limiting the data to a certain number of candidates in the top of the list or to a top few percent of the candidates in the data.  
         [0073]     Next, the CPU  11  judges whether or not the authentication result transmitted from the fingerprint authentication module  30  was successful (Step S 106 ). If authentication is successful (Step S 106 : YES), the CPU  11  judges whether or not a plurality of candidates were extracted (Step S 107 ). If the authentication had failed (Step S 106 : NO), the processing proceeds to Step S 113 .  
         [0074]     In Step S 107 , when it is judged that a plurality of candidates were extracted (Step S 107 : YES), the CPU  11  reads out the login ID corresponding to the registration numbers of the respective plurality of candidates that were added to the data from the non-volatile memory  18 , and, for example, as is shown in  FIG. 6 , displays them in the display section  20  in decreasing order of the degree of matching as the login ID. By this, the user is prompted to select the login ID (Step S 108 ). By displaying in decreasing order of the degree of matching, since the candidate that has a higher probability of being selected by the user is displayed close to the top, it is possible for the user to find easily the selection candidate from the list of candidates. In addition, when the number of candidates is large, if the display is made by restricting the candidates to the top few or to the top few percent, since the display is made by limiting to the candidates that have a high probability of being selected by the user, it is possible for the user to find easily the selection candidate from the list of candidates.  
         [0075]     When it is judged that a plurality of candidates have not been extracted (Step S  107 : NO), the processing proceeds to Step S 110 .  
         [0076]     When the user selects using the operation section  19 , following the display in Step S 108 , one of the candidates of the login IDs displayed in the display section  20 , the selection information of the selection login ID is input to the CPU  11  (Step S 109 ).  
         [0077]     In Step S 110 , the CPU  11  reads out, from the non-volatile memory  18  into the RAM  14 , the password corresponding to the selected login ID (if the processing jumped to this step from Step S 109 ), or the login ID and password corresponding to the registration number (if the processing jumped to this step from Step S 107 : NO).  
         [0078]     Next, the CPU  11  displays the login screen which displays the login ID read out in Step S 107  and a part of the password in the display section  20 , and prompts the user to make the completion input of the password (Step S 111 ). For example, as is shown in  FIG. 7 , if the password has eight characters, the leading six characters of the password are input automatically and are displayed by six asterisks ‘*’ and the last asterisk ‘*’ is followed by the display of 2 underscored. characters. Following this display, the user makes the completion input of the password from the operation section  19 . In the case of the example shown in  FIG. 7 , the user makes the completion input of the remaining two characters in the part displayed by underscores. By displaying the number of characters to be input using underscores etc., for example, even when a password with a large number of characters is being displayed, the user can immediately recognize which characters are to be input.  
         [0079]     With this, the completion input of the password is made to the CPU  11  (Step S 112 ). In the case of the example shown in  FIG. 7 , the login screen displays two asterisks ‘*’ in addition at the end of the six asterisks ‘*’ displayed earlier.  
         [0080]     By making the user carry out completion input in this manner, even if the collation is successful while wrongly recognizing another person as the genuine user, since that other person cannot login as it is, but has to complete the password, another person logging in with the login ID and password of the genuine user is suppressed.  
         [0081]     In Step S 106 , if authentication has failed (Step S 106 : NO), the operation proceeds to Step S 113 , and the CPU  11  displays, in the. display section  20 , a login screen with the login ID and password fields empty, and prompts the user to enter the login ID and password. Following this instruction, the user enters all the characters of the login ID and password through the operation section  19 .  
         [0082]     For example, if the fingerprint registration condition is bad, and even if the fingerprint authentication has failed in spite of the user being the genuine user, it is possible for the user to login by inputting all the characters of the login ID and password.  
         [0083]     In Step S 114 , all the characters of the login ID and password are input to the CPU  11 .  
         [0084]     In Step S 112  or 0  Step S 114 , when the login ID and password and input and logging in is made, the CPU  11  refers to the login IDs and passwords stored in the non-volatile memory  18  to cross-check with the entered login ID and password, and carries out authentication of the entered login ID and password (Step S 115 ). If the authentication is successful (Step S 115 : YES), the CPU  11  outputs the use permission signal to the image forming apparatus (Step S 116 ). If the authentication has failed (Step S 115 : NO), the CPU  11  outputs the use prohibit signal to the image forming apparatus (Step S 117 ).  
         [0085]     In the above manner, according to the present preferred embodiment, at the time of automatically inputting the login ID and password in the login ID field and the password field of the login input screen due to success of biometric authentication, since the entire password is not input automatically but a part of it is made to be entered by the user, not only that the input becomes simple at the time of logging in, but also logging in by another person using the login ID and password of the genuine user is suppressed. In addition, in the case when a plurality of candidates are extracted, since a plurality of candidates are displayed and the user is made to select among them, it is possible to definitively identify the desired user.  
         [0086]     Although in the present preferred embodiment, in the case when a plurality of candidates of user are present, although the login IDs were displayed, it can be any information that can be recognized by the user instead.  
         [0087]     Although in the present preferred embodiment the trailing part of the password was made the target of completion input by the user, it can also be the leading part or a middle part of the password. Since it is easy for the user to remember the leading and the trailing parts, it is desirable to use these for the completion input.  
         [0088]     Further, although in the present preferred embodiment, the example of using a number of underscores equivalent to the number of characters of the completion input was explained as an example of the display for prompting for and accepting the input of completion input from the user, the present invention shall not be construed to be limited to this mode of display, and, for example, the display mode can also be line the one shown in  FIG. 8 . In the example of this figure, considering, for the sake of explanation, that the password has eight characters similar to that shown in  FIG. 7 , in addition to carrying out the automatic input of the leading six characters of the password and displaying them by six asterisks ‘*’, the prompt following the last asterisk character ‘*’ is displayed by a prompt character (for example, by a blinking cursor). In the example of this figure, the user carries out completion input of the remaining characters according to the prompt characters. Here, when the number of characters in the password differs depending on the user, only the genuine user can know how many characters have to be input following the prompt. In this manner, in the case of the present preferred embodiment, it is possible to make the number of characters of the password have the same kind of meaning as the password itself, and is desirably suitable for achieving security.  
         [0089]     Although in the present preferred embodiment, the fingerprint data was stored in the non-volatile memory  36  of the fingerprint authentication module  30  while establishing correspondence with the registration number, the login ID and password were stored in the non-volatile memory  18  of the apparatus main unit  10  while establishing correspondence with the registration number, and the login ID and password corresponding to the fingerprint were identified by transmitting the registration number from the fingerprint authentication module  30  to the apparatus main unit  10  when the authentication by the fingerprint authentication module  30  was successful, it is also possible to store the login IDs and passwords in the non-volatile memory  36  of the fingerprint authentication module  30 , and to transmit to the apparatus main unit  10  the login ID and the password stored in the non-volatile memory  36  from the fingerprint authentication module  30  when the authentication by the fingerprint authentication module  30  is successful.  
         [0090]     Although in the present preferred embodiment, the fingerprint authentication module  30  was configured to be controlled by a CPU  31  that is other than the CPU  11  of the apparatus main unit  10 , it is also possible to configure it so that it is controlled by the CPU  11  of the apparatus main unit  10 .  
         [0091]     Although in the present preferred embodiment, the user authentication method according to the present invention was used for apparatus use permission of the image forming apparatus, it is also possible to use the user authentication method according to the present preferred embodiment at the time of accessing the image data, document data, personal address books used for Scan to E-mail that are stored in the hard disk  17 .  
         [0092]     Although in the present preferred embodiment, the user authentication method according to the present invention was applied for an image forming apparatus, it goes without saying that the present invention can as well be applied to other apparatuses equipped with authentication functions, such as, in addition, personal computers, ATMs (Automatic Teller Machines), input/output control apparatuses etc.  
         [0093]     Although in the present preferred embodiment, fingerprints were used for the authentication module, the present invention can also be applied to other biological information such as, for example, veins, face, iris, retina, voice prints, handwriting etc.  
         [0094]     According to the present invention, at the time of automatically inputting the login ID and password in the login ID field and password field upon success of a biometric authentication, since all of the characters in the password are not input automatically but a part of it is being made to be input by the user, not only that the input at the time of logging in becomes simpler but also logging in by another person using the login ID and password of the genuine user is suppressed. In addition, when several candidates are extracted, since several candidates are displayed and the user is made to select among them, it is possible to identify the desired user definitely.