Abstract:
A communication apparatus for authenticating a plurality of people is provided. The communication apparatus includes an input device for obtaining a first set of data for identifying a first person of the people, a receiver for receiving a second set of data for identifying a second person of the people, and a memory for storing a plurality of data for identifying at least two of the people. The communication apparatus includes a controller coupled to the input device, the receiver and the memory. The controller is configured to limit a particular function of the communication apparatus, to compare each of the first set of data and the second set of data with the stored data, and to stop limiting the particular function upon finding out that one and another of the two people identified by the stored data coincide with the first person and the second person, respectively.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2006-017242 filed on Jan. 26, 2006; the entire contents of which are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to apparatus for personal authentication and in particular to a communication apparatus having an authentication capability.  
       DESCRIPTION OF THE BACKGROUND  
       [0003]     A variety of authentication systems is known which is used in communications for secure on-line trade, for secure payment and so on by electronic money stored, e.g., in a built-in non-contact IC chip of a communication apparatus.  
         [0004]     A communication apparatus is known which is configured to obtain an image of a person. The communication apparatus may compare that image with another image of the person stored in advance. The communication apparatus may make a phone call and send a piece of information resulting from the comparison to an opposite end of the call so that the person may be identified at the opposite end.  
         [0005]     The opposite end, having a database including a plurality of data regarding the person, may receive the information and retrieve some relevant data out of the database based on the information so that the person may be identified. The above communication apparatus is disclosed in Japanese Patent Publication (Kokai), No. 2004-21748.  
         [0006]     A TV call apparatus is known which is configured to have a camera and a database that may include an image of a right person to use the TV call apparatus. During a TV call, the TV call apparatus may compare an image of a person photographed by the camera with the image of the right person. The TV call apparatus accepts a plurality of commands entered by its user in a case where the above two images coincide. The TV call apparatus cancels the entered commands in a case where the above two images do not coincide. The above TV call apparatus is disclosed in Japanese Patent Publication (Kokai), No. 2000-137809.  
         [0007]     An image of a person is very often an image of his or her face. A variety of methods of face authentication is known, i.e., extracting some features of a face of a person to be authenticated and comparing them with an image included in a database in terms of those features. Some methods of face authentication are disclosed in a reference listed here: Akamatsu, “Computer recognition of human face-A survey-”, IECEJ Trans. Vol. J80-A, No.8, pp.1215-1230, August 1997.  
         [0008]     A user of a communication apparatus having a particular function like having dealings or settling accounts through the Internet, e.g., may require an approval of a supervisor for using the function. In such a case, the supervisor as well as the user should be authenticated to make the use of the function safer.  
         [0009]     The above, so called double authentication helps keep the user from overusing the function without the approval from the authenticated supervisor, particularly in a case where the user is a child or a youngster. It is apparent that neither the above communication apparatus nor the above TV call apparatus may be applied to the above double authentication.  
       SUMMARY OF THE INVENTION  
       [0010]     Accordingly, an advantage of the present invention is that a communication apparatus for personal authentication may be used safely.  
         [0011]     To achieve the above advantage, one aspect of the present invention is to provide a communication apparatus capable of authenticating a plurality of people. The communication apparatus includes an input device configured to obtain a first set of data for identifying a first person of the people, a receiver configured to receive a second set of data for identifying a second person of the people, and a memory configured to store a plurality of data for identifying at least two of the people. The communication apparatus also includes a controller configured to limit a particular function of the communication apparatus, to compare the first set of data and the stored data, to compare the second set of data and the stored data, and to stop limiting the particular function upon finding out that one and another of the two people identified by the stored data coincide with the first person and the second person, respectively. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]      FIG. 1  is a conceptual diagram of a network including a communication apparatus of a first embodiment of the present invention.  
         [0013]      FIG. 2  shows an external view of the communication apparatus shown in  FIG. 1 .  
         [0014]      FIG. 3  is a block diagram of the communication apparatus shown in  FIG. 1 .  
         [0015]      FIG. 4  is a flow chart of a process of the first embodiment of the present invention.  
         [0016]      FIG. 5  is a flow chart of a process of a second embodiment of the present invention.  
         [0017]      FIG. 6  is a flow chart of a process of a third embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]     A first embodiment of the present invention will be described with reference to  FIGS. 1-4 .  FIG. 1  is a conceptual diagram of a network including a mobile phone  1 , i.e., a communication apparatus of the first embodiment. The mobile phone  1  is connected to a network  6  by sending and receiving radio signals to and from a base station (not shown) included in the network  6 .  
         [0019]     On the right hand side of  FIG. 1 , there is shown another mobile phone  7  connected to the network  6  in a similar manner. The mobile phone  1  has a built-in camera, and may be used for a TV call with the mobile phone  7 .  
         [0020]     The mobile phone  1  has a non-contact type IC chip usable for electronic money (e-money). The mobile phone  1  may limit an operation of the non-contact type IC chip, and may stop limiting the operation if a set of predetermined requirements are satisfied as follows.  
         [0021]     Firstly, the mobile phone  1  is required to detect a coincidence between a person at the mobile phone  1  photographed by the camera of the mobile phone  1  and a person of a first category registered in the mobile phone  1 , as a result of personal authentication. Secondly, the mobile phone  1  is required to detect another coincidence between a person at the mobile phone  7  and a person of a second category registered in the mobile phone  1 , as another result of personal authentication.  
         [0022]     The first category is “limited function users”, and no less than one person may be registered in the first category. The second category is “supervisors”, and no less than one person may be registered in the second category.  
         [0023]      FIG. 2  shows an external view of the mobile phone  1 . The mobile phone  1  has a first case  11  and a second case  12  connected to each other via a connecting portion  13  in such a way that the first case  11  may be flipped over the second case  12 .  
         [0024]     The first case  11  has a camera  15  and has a display  16  formed by, e.g., a liquid crystal device, and an earpiece  17 . The camera  15  may take a static picture. The camera  15  may take a moving picture. The display  16  may present a plurality of letters, numerals, symbols, pictures and a cursor.  
         [0025]     The second case  12  has a set of user controls (hereinafter called the user control)  18  in an area enclosed by a dashed line. The user control  18  includes a plurality of numeric keys each of which may toggle a numeral and a few letters and symbols. The user control  18  includes a navigation key usable for moving the cursor up, down, left or right. The user control  18  includes a plurality of soft keys each of which may be assigned a specific function. The second case  12  has a microphone  19 .  
         [0026]      FIG. 3  is a block diagram of the mobile phone  1 . There is shown a first antenna  21  on an upper, left hand side of  FIG. 3 . The first antenna  21  may be used for sending and receiving radio signals to and from the base station included in the network  6 . The first antenna  21  is connected to a duplexer  22  and is linked to a transmitter  23  and a receiver  24 , respectively, via the duplexer  22 .  
         [0027]     The transmitter  23  may encode a piece of outgoing information, and may modulate, up-convert and amplify an encoded signal to generate an outgoing radio signal. The transmitter  23  may further emit the outgoing radio signal into the air toward the base station via the duplexer  22  and the first antenna  21 .  
         [0028]     The receiver  24  may receive an incoming radio signal emitted by the base station via the first antenna  21  and the duplexer  22 . The receiver  24  may amplify, down-convert and demodulate the incoming radio signal, and may further decode a demodulated output to extract a piece of incoming information.  
         [0029]     An input port of the transmitter  23  and an output port of the receiver  24  are connected to a controller  27 , respectively. The controller  27  is formed by, e.g., a processing device like a microprocessor or a digital signal processor. The controller  27  may monitor and control each part and a whole of the mobile phone  1 .  
         [0030]     The controller  27  may send a plurality of outgoing digital data to the transmitter  23 , and may obtain a plurality of incoming digital data carried by a plurality of radio signals received by the receiver  24 . In  FIG. 3 , there are classified a plurality of main processes done by the controller  27  and each of them is shown as a dashed rectangle in the controller  27 . Each of those main processes will be explained eight paragraphs later.  
         [0031]     The mobile phone  1  has a codec  30  that is connected to the transmitter  23 , the receiver  24  and the controller  27 . The codec  30  is connected to the camera  15 , the earpiece  17  and the microphone  19 , each of which has been explained with reference to  FIG. 2 .  
         [0032]     The codec  30  may digitize and encode an analog voice signal picked up by the microphone  19 , and may send a plurality of encoded digital voice data to the transmitter  23 . The codec  30  may obtain and decode a plurality of digital voice data carried by the radio signals received by the receiver  24  to convert into an analog form, and may drive the earpiece  17  with a resultant analog voice signal. The codec  30  may encode an image signal of a picture photographed by the camera  15 , and may send a plurality of encoded image data to the controller  27 . The controller  27  may send a plurality of image data and a plurality of text data to the display  16  via a display interface  32 .  
         [0033]     The user control  18 , earlier explained with reference to  FIG. 2 , is connected to the controller  27  and may send information on which numeral, letter or symbol has been entered by being operated. The user control  18  may be operated to make a TV call, and may be operated to end a TV call. The user control  18  may be operated to perform face authentication of a person photographed by the camera  15 , and to perform face authentication of a person being the other party of the TV call.  
         [0034]     The mobile phone  1  has a memory  35  in which a first database  35   a  and a second database  35   b  may be formed. Each entry of the first database  35   a  is a set of image data of a face (face image data) of a person of the first category. Each entry of the second database  35   b  is a set of face image data of a person of the second category.  
         [0035]     The mobile phone  1  has a non-contact type IC chip  38  and a second antenna  39 . The second antenna  39  may be either directly or indirectly (via another, not shown circuit element) linked to the IC chip  38 . The IC chip  38  and the antenna  39  may conform, but not limited, to a standard of a non-contact type IC card which may send and receive radio signals to and from a reader/writer on a frequency of 13.56 MHz. The IC chip  38  may have an e-money function, i.e., may hold a set of data on a carried amount of money, and may be used for settling accounts, under control of the controller  27 , by updating the data as the carried amount of money either increases or decreases.  
         [0036]     An example of how to settle accounts by the e-money function will be described in a case of shopping at a store. Suppose that there is installed a reader/writer, a terminal of an accounting network, in the store. Suppose an amount of money to be settled is set in the reader/writer and the mobile phone  1  approaches the reader/writer close enough. The IC chip  38  then receives a signal sent from the reader/writer via the second antenna  39 , including the information on the amount of money to be settled.  
         [0037]     The IC chip  38  updates the data of the carried amount of money to be decreased by as much as the settled amount of money. The IC chip  38  gives a reply to the reader/writer via the second antenna  39 , saying that the account has been settled. The reader/writer then reports to a host of the accounting network on the settlement and the settled amount of money. The host then continues a series of steps to be processed in the network.  
         [0038]     An e-mail transceiver  27   a , a first one of the main processes of the controller  27 , will be explained as follows. The e-mail transceiver  27   a  may start working under control of the controller  27  if the user control  18  is operated to handle e-mails.  
         [0039]     The e-mail transceiver  27   a  may arrange an outgoing e-mail including an e-mail address of an addressee, a title and a message, each of which may be formed by a plurality of numerals, letters and symbols entered on the user control  18 . The e-mail transceiver  27   a  may provide the transmitter  23  with the outgoing e-mail to be sent to an e-mail server (not shown) of the network  6  via the duplexer  22 , the first antenna  21  and a base station (not shown) of the network  6 , under control of the controller  27 .  
         [0040]     The e-mail transceiver  27   a  may receive an incoming e-mail sent from the e-mail server via the base station, the first antenna  21 , the duplexer  22  and the receiver  24 , under control of the controller  27 . The e-mail transceiver  27   a  may store the received e-mail either in the memory  35  or in another memory (not shown), and may once stop working.  
         [0041]     The e-mail transceiver  27   a  may restart working under control of the controller  27  if the user control  18   a  is operated to do so. The e-mail transceiver  27   a  may provide the display  16  via the display inter-face  32  with a list of received e-mails stored in the memory  35  or else so that the list may be presented on the display  16 . The e-mail transceiver  27   a  may select one of the stored e-mails as selected on the user control  18 , and may provide the display  16  via the display inter-face  32  with the selected e-mail so that the selected e-mail may be presented on the display  16 .  
         [0042]     A browser  27   b , a second one of the main processes of the controller  27 , will be explained as follows. The browser  27   b  is a process to access a web site that may be linked through the network  6 . The browser  27   b  may be activated and start accessing a web site if the user control  18  is operated to start web-browsing.  
         [0043]     The browser  27   b  may form a set of data for accessing the web site including an address of the web site entered on the user control  18 , and may provide the transmitter  23  with the formed set of data. The transmitter  23  generates an accessing signal based on the formed set of data and sends the accessing signal to the base station included in the network  6  via the duplexer  22  and the first antenna  21 . That accessing signal then goes forward to the web site through the network  6 .  
         [0044]     The mobile phone  1  may be thereby linked to the web site, which may send back a responding signal including a set of responding information. The responding signal may reach the base station in a backward direction through the network  6 , and then reach the mobile phone  1 . The browser  27   b  may obtain the set of responding information via the first antenna  21 , the duplexer  22  and the receiver  24 . The browser  27   b  may provide the display  16  via the display interface  32  with the responding information to be presented.  
         [0045]     An e-money limiter  27   c , a third one of the main processes of the controller  27 , will be explained as follows. The e-money limiter  27   c  may limit the e-money function by limiting an operation of the IC chip  38  unless a set of predetermined requirements are satisfied, which will be described with reference to  FIG. 4  later. The e-money limiter  27   c  may stop limiting the e-money function if the set of predetermined requirements are satisfied.  
         [0046]     The e-money limiter  27   c  may deactivate the IC chip  38 . The e-money limiter  27   c  may have the IC chip  38  give a reply to a reader/writer via the second antenna  39  saying that the e-money function is being ineffective. The limitation imposed on the e-money function may be, but not limited to, regarding if the use of the e-money function is allowed or not, how long the use is allowed, for what the use is allowed, and to what extent the use is allowed.  
         [0047]     A face authenticator  27   d , a fourth one of the main processes of the controller  27 , will be explained as follows. The face authenticator  27   d  may obtain a set of face image data of a photographed person sent from the camera  15  to the controller  27  via the codec  30 . The face authenticator  27   d  may detect an inclination of the face and may detect a location of each element of the face out of the face image data, may determine a location of each feature point (a center of an eye, an end of a lip, etc.), may measure a distance between one feature point and another feature point, and may consequently extract a feature value of the face image data of the photographed person.  
         [0048]     The face authenticator  27   d  may compares the feature value of the photographed person with a feature value of a person of the first category registered in the first database  35   a . The face authenticator  27   d  may detect a coincidence between the person photographed by the camera  15  and the registered person of the first category (limited function user) by such a known method of face authentication (refer to Akamatsu, e.g.).  
         [0049]     During a TV call between the mobile phone  1  and the mobile phone  7 , the mobile phone  1  may receive a signal carrying a plurality of digital data including a face image data of a person at the mobile phone  7  through the network  6 . The signal is received by the receiver  24  via the first antenna  21  and the duplexer  22 . The controller  27  may obtain the face image data of the person at the mobile phone  7 .  
         [0050]     The face authenticator  27   d  may extract a feature value of the face image data of the person at the mobile phone  7  by the method described above. The face authenticator  27   d  may compare the feature value of the person at the mobile phone  7  with a feature value of a person of the second category registered in the second database  35   b . The face authenticator  27   d  may detect a coincidence between the person at the mobile phone  7  and the registered person of the second category (supervisor).  
         [0051]     How the face authentication is done by the mobile phone  1  will be described with reference to  FIG. 4 , a flow chart of a process of the first embodiment. After the process starts (“START”), the e-money limiter  27   c  limits the e-money function by limiting the operation of the IC chip  38  (step “S 1 ”). For limiting the operation, the e-money limiter  27   c  may deactivate the IC chip  38 . For limiting the operation, the e-money limiter  27   c  may have the IC chip  38  give an ineffective reply.  
         [0052]     The user control  18  is operated by an authenticated operator so that the e-money limiter  27   c  may limit the e-money function. The operator may be authenticated by a face. The operator may be authenticated by a password entered on the user control  18 . The e-money function may be limited as a default without such operation or authentication.  
         [0053]     The controller  27  waits for the user control  18  to be operated in a predetermined way to stop limiting the e-money function (“NO” of step “S 2 ”). If the user control  18  is operated in that way (“YES” of step “S 2 ”), the mobile phone  1  makes a TV call to the mobile phone  7  (step “S 3 ”). The TV call may be either automatically made or manually made, i.e., by a series of operation on the user control  18 . An order of the steps “S 2 ” and “S 3 ” may be reversed (i.e., the user control  18  is operated to stop limiting the e-money function after the TV call is made).  
         [0054]     If the user control  18  is operated for performing face authentication (“YES” of step “S 4 ”), the controller  27  has the face authenticator  27   d  perform face authentication of a person photographed by the camera  15 . If the face authenticator  27   d  detects a coincidence between the photographed person and a registered person of the first category (“YES” of step “S 5 ”), the controller  27  has the face authenticator  27   d  perform face authentication of a person at the mobile phone  7 . If the face authenticator  27   d  detects a coincidence between the person at the mobile phone  7  and a registered person of the second category (“YES” of step “S 6 ”), the controller  27  has the e-money limiter  27   c  stop limiting the operation of the IC chip  38  (step “S 7 ”).  
         [0055]     After the limitation is stopped, allowed is a certain extent of use, that may be an upper amount of e-money, may be an object of use (shopping at a particular store, e.g.), may be a period of time of use, and may be a combination of those. The controller  27  may be configured to stop limiting the e-money function only during the TV call. For the face authentication at the step “S 6 ”, the face authenticator  27   d  may search for a registered person of the second category with reference to a phone number of the mobile phone  7 , and may do so without reference to the phone number of the mobile phone  7 .  
         [0056]     The controller  27  waits for the user control  18  to be operated to end the TV call (“NO” of step “S 8 ”). After the operation, the TV call is ended (“YES” of step “S 8 ”). The e-money limiter  27   c  waits for the allowed extent of use to be reached (“NO” of step “S 9 ”). If the e-money limiter  27   c  finds out that the allowed extent of use is reached, the controller  27  ends the flow of the process (“YES” of step “S 9 ”). In a case where the controller  27  is configured to stop limiting the e-money function only during the TV call, an order of the steps “S 8 ” and “S 9 ” should be reversed.  
         [0057]     Before the user control  18  is operated for performing face authentication (“NO” of step “S 4 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call. Unless the face authenticator  27   d  detects a coincidence between the photographed person and a registered person of the first category (“NO” of step “S 5 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call. Unless the face authenticator  27   d  detects a coincidence between the person at the mobile phone  7  and a registered person of the second category (“NO” of step “S 6 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call.  
         [0058]     An order of the steps “S 5 ” and “S 6 ” may be reversed. The first embodiment of the present invention may be applied not only to an e-money function but also to another function that may be used through the browser  27   b  and may be limited in a certain sense, e.g., settling accounts for on-line dealings (shopping, banking, etc.), a request in an on-line administrative process and so forth. The first embodiment of the present invention may be applied to no less than two functions.  
         [0059]     According to the first embodiment described above, a communication apparatus may improve security for a right person using a particular function by stopping limiting the function based on double authentication of a limited function user and a supervisor.  
         [0060]     A second embodiment of the present invention will be described with reference to  FIG. 5 . As a communication apparatus of the second embodiment is a same as the mobile phone  1  of the first embodiment,  FIGS. 1-3  are also referred to.  FIG. 5  is a flow chart of a process of the second embodiment.  
         [0061]     After the process starts (“START”) in  FIG. 5 , each of a series of steps “S 11  ”-“S 16 ” is a same as the corresponding one of the steps “S 1 ”-“S 6 ” in  FIG. 4 , and its explanation is omitted. An order of the steps “S 12 ” and “S 13 ” may be reversed. An order of the steps “S 15 ” and “S 16 ” may be reversed.  
         [0062]     If the face authenticator  27   d  detects a coincidence between a person photographed by the camera  15  and a registered person of the first category (“YES” of step “S 15 ”) and a coincidence between a person at the mobile phone  7  and a registered person of the second category (“YES” of step “S 16 ”), the controller  27  waits for an approval to stop limiting the e-money function to be sent from the mobile phone  7 . The approval is expressed by a specific signal generated by a series of key operation on the mobile phone  7 . The specific signal is multiplexed with a voice signal during the TV call and sent from the mobile phone  7 . The controller  27  may separate and detect the specific signal out of the voice signal.  
         [0063]     Upon detecting the specific signal sent from the mobile phone  7  and receiving the approval (“YES” of step “S 17 ”), the controller  27  has the e-money limiter  27   c  stop limiting the operation of the IC chip  38  (step “S 18 ”). Each of a following series of steps “S 19 ”, “S 20 ” and “END” is a same as the corresponding one of the steps “S 8 ”, “S 9 ” and “END” in  FIG. 4 , respectively, and its explanation is omitted.  
         [0064]     Before the user control  18  is operated for performing face authentication (“NO” of step “S 14 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call. Unless the face authenticator  27 d detects a coincidence between the photographed person and a registered person of the first category (“NO” of step “S 15 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call.  
         [0065]     Unless the face authenticator  27   d  detects a coincidence between the person at the mobile phone  7  and a registered person of the second category (“NO” of step “S 16 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call. Before receiving the approval (“NO” of step “S 17 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call.  
         [0066]     In a case where the controller  27  is configured to stop limiting the e-money function only during the TV call, an order of the steps “S 19 ” and “S 20 ” should be reversed. The second embodiment of the present invention may be applied to another function that may be limited in a certain sense. The second embodiment of the present invention may be applied to no less than two functions, as the first embodiment. The specific signal expressing the approval may be sent from the mobile phone  7  in a way other than being multiplexed with the voice signal.  
         [0067]     According to the second embodiment described above, a communication apparatus may improve security as in the first embodiment, and may further improve the security by sending an approval from a supervisor to a limited function user.  
         [0068]     A third embodiment of the present invention will be described with reference to  FIG. 6 . As a communication apparatus of the third embodiment is a same as the mobile phone  1  of the first embodiment,  FIGS. 1-3  are also referred to.  FIG. 6  is a flow chart of a process of the third embodiment.  
         [0069]     After the process starts (“START”) In  FIG. 6 , each of a series of steps “S 21 ”-“S 24 ” is a same as the corresponding one of the steps “S 11 ”-“S 14 ” in  FIG. 5 , and its explanation is omitted. An order of the steps “S 22 ” and “S 23 ” may be reversed.  
         [0070]     If the user control  18  is operated for performing face authentication (“YES” of step “S 24 ”), the controller  27  sets a number of repetitive authentication to one (step “S 25 ”). Each of a following series of steps “S 26 ” through “S 31 ” (“YES”) and “END” is a same as the corresponding one of the steps “S 14 ” through “S 20 ” (“YES”) and “END” in  FIG. 5 , respectively, and its explanation is omitted. An order of the steps “S 26 ” and “S 27 ” may be reversed.  
         [0071]     Unless the face authenticator  27   d  detects a coincidence between a person photographed by the camera  15  and a registered person of the first category (“NO” of step “S 26 ”), the controller  27  finds out if the number of repetitive of authentication reaches a predetermined upper value N.  
         [0072]     If the number of repetitive authentication is less than N (“YES”of step “S 32 ”), the controller  27  adds one to the number (step “S 33 ”), and goes back to the step “S 26 ” to repeat performing the face authentication. As a probability of successful authentication may be influenced and lowered by, e.g., a condition of taking pictures even though the person to be authenticated has been registered in one of the first category and the second category, such a repetition of no greater than N times may raise the probability to a certain degree.  
         [0073]     If the number of repetitive authentication is no less than N (“NO” of step “S 32 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call. Before the user control  18  is operated for performing face authentication (“NO” of step “S 24 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call. Before receiving the approval (“NO” of step “S 28 ”), the controller  27  keeps limiting the e-money function and waits for the user control  18  to be operated to end the TV call.  
         [0074]     In a case where the controller  27  is configured to stop limiting the e-money function only during the TV call, an order of the steps “S 30 ” and “S 31 ” should be reversed. The third embodiment of the present invention may be applied to another function that may be limited in a certain sense. The third embodiment of the present invention may be applied to no less than two functions, as the first embodiment and as the second embodiment. The specific signal expressing the approval may be sent from the mobile phone  7  in a way other than being multiplexed with the voice signal, as in the second embodiment.  
         [0075]     The controller  27  may be configured to repeat performing the face authentication before a certain period of time passes since the user control  18  is operated to perform the face authentication. In a case where no approval from the mobile phone  7  is required to stop limiting a particular function as in the first embodiment, the controller  27  may be configured to repeat performing the face authentication before the number of repetitive authentication reaches N, and the controller  27  may be configured to repeat performing the face authentication before a certain period of time passes since the user control  18  is operated to perform the face authentication.  
         [0076]     According to the third embodiment of the present invention described above, a communication apparatus may further raise a probability of successful authentication by repeating the authentication process to a certain extent.  
         [0077]     In the first through the third embodiments described above, a way of authentication may not be limited to face authentication, but may depend on other kinds of living body information like a fingerprint, an iris, a voiceprint, and may depend on a password formed by a permutation of numerals, letters and symbols. A way of authenticating a limited function user may be different from a way of authenticating a supervisor. The present invention may be applied to a communication apparatus other than a mobile phone capable of obtaining and receiving information for personal authentication with no regard if it is either wired or wireless.  
         [0078]     The particular hardware or software implementation of the present invention may be varied while still remaining within the scope of the present invention. It is therefore to be understood that within the scope of the appended claims and their equivalents, the invention may be practiced otherwise than as specifically described herein.