KR20010084889A - A credit card service method using code image and apparatus thereof - Google Patents

Abstract

The present invention relates to a credit card service method and apparatus using a physically or electronically represented code image, and in the credit transaction method of receiving an electronic commerce or a paid service through a communication network and paying for the same.

Inputting information related to a credit transaction including a credit card number; Inputting a coded image represented physically or electronically into a credit card; Extracting code information of a user from the input code image by a predetermined decoding algorithm; Comparing whether the extracted code information is identical with code information set in relation to the credit transaction information, and determining whether the user is a valid credit card holder; And establishing a credit card transaction if it is determined that the user is a legitimate user in the determination step, and an image device such as a camera or a scanner together with a credit card number normally input by a keyboard in an authentication process during electronic commerce. Code images entered through can be used for user authentication, ensuring secure credit transactions.

Description

A credit card service method using code image and apparatus

The present invention relates to a credit card service method and apparatus using a physically or electronically represented code image, and in particular, to issue a credit card displaying a code image related to specific information to a user, and the information embedded in the code image of the card. The present invention relates to a credit card service method and apparatus for providing various services.

With the advent of the credit information society, credit cards have become an indispensable tool in modern society. For this reason, credit cards provide various additional services in parallel. However, in general, it is difficult for general users to know what kind and benefit of the service added to the credit card is provided without information such as DM from the card company. In addition, the service score accumulation system provided to the user according to the use history of the mileage service, etc. can not be easily retrieved, and it is not very efficient because the mileage-only telephone service must be used.

The present invention has been made in an effort to provide a credit card providing method capable of performing a credit transaction using a code image displayed by encoding unique code information of a user.

Another technical problem to be solved by the present invention is a computer and a device for performing a credit transaction using a credit card including credit card information and a code image, and a program for executing the method on a computer. To provide a recording medium.

Another technical problem to be achieved by the present invention is to provide a credit card in which code information is displayed in the form of a code image for application to a credit transaction service.

1 is a view showing an example of the overall configuration of a computer network system for carrying out the present invention.

2 is a diagram showing an example of a credit card 16 issued to a user in a server.

3 is an example of a code conversion table used for the encoding and decoding algorithm.

4A illustrates an example of contents stored in a user database of a server, FIG. 4B illustrates an example of information displayed as a code image, and FIG. 4C illustrates an example of contents stored in a code database.

5 is a flowchart illustrating a process of providing a credit card to a user according to the present invention.

6 is a flowchart illustrating a method for servicing using a credit card according to the present invention.

In order to achieve the above object, the credit card providing method according to the present invention,

Applying for user registration with a server; Assigning credit card information and code information to a user and storing the same; Converting the code information into a code image that is physically or electronically encoded by encoding the code information by a predetermined encoding algorithm; Displaying the credit card information on the credit card medium together with the code image; And providing the credit card medium to the user.

In order to achieve the above another problem, the credit transaction method according to the present invention,

In the credit transaction method of receiving and paying for electronic commerce or paid service through a communication network,

Inputting information related to a credit transaction including a credit card number; Inputting a coded image represented physically or electronically into a credit card; Extracting code information of a user from the input code image by a predetermined decoding algorithm; Comparing whether the extracted code information is identical with code information set in relation to the credit transaction information, and determining whether the user is a valid credit card holder; And if it is determined that the legitimate user in the determination step, characterized in that it comprises a step of establishing a credit card transaction.

In order to achieve the above another problem, the credit transaction service apparatus according to the present invention,

Allocating credit information and related code information to each user, encoding the code information by an encoding algorithm, converting the code information into a code image that can be expressed physically or electronically, and displaying it on a credit card to provide to the user. Credit card provider; A storage unit having a code database storing credit transaction information issued to a user and code information related thereto; Receives credit information from the user, receives the code image displayed on the user's credit card, decodes it by a decoding algorithm, extracts the code information embedded in the code image, and sets a code related to the credit transaction information input by the user. And a judging unit comparing the extracted information with the extracted code information to determine whether the holder is a valid credit card holder.

In order to achieve the above another object, the credit card medium according to the present invention,

Tangible media having a physical shape; A code information unit in which code information assigned to a user is encoded by a predetermined encoding algorithm and converted into a physical code image on the surface of the medium; And a credit information unit on which information required for a credit transaction of the user is displayed.

Here, the code image is a predetermined shape, color, pattern or these generated by converting one or more characters or numbers included in the code information by a predetermined code conversion table for mapping each letter and number to a predetermined color, respectively. Characterized in that the combination of the image.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a view showing an example of the overall configuration of a computer network system for carrying out the present invention.

The credit card server computer 12 includes a code engine 12c in which an algorithm for encoding and decoding unique code information given to a user is implemented. The credit card server computer 12 includes information about all users registered in the server to use the service. A user database 12a for storing and a code database 12b for storing code information assigned to a user registered in the server are provided (see FIGS. 4A, B, and C). The credit card 16 issued to the user includes a code image 16a obtained by encoding unique code information and credit transaction information 16b required for a credit transaction. The service server computer 13 refers to a server through which a user can receive a service using a credit card.

The server 12 encodes the user's code information using color or color and pattern, and implements an encoding algorithm for generating a code image, and decodes the code image to restore the original code information. Software having implemented a decoding algorithm is provided. The user computer 15 can download the decoding program from the server computer 12 and install it in advance. The program may be provided in the form of a single software package or in the form of a plug-in or integrated circuit chip for use in an Internet browser. Then, the user computer 15 can perform the function of directly extracting the code information by decoding the code image without going through the server computer 12. If the user computer 15 has not downloaded the decoding program, it should connect to the server computer 12 to perform decoding. On the other hand, in the case of the encoding process, it is common to issue code by encoding the code information in the credit card server and displaying the code image directly on the credit card.

The server 12 converts the user's code information into a code image by the encoding software 12c and then displays it on a credit card medium 16 which can be physically represented as a credit card and issues it to the user. And, the credit card 16 (see FIG. 2) is a credit card (BC card, national card VISA card), prepaid card, postpaid card as well as all kinds of cards issued for credit purposes for the purpose of certain services ( For example, public telephone cards, train cards, cards that can be used in certain chain stores, etc.), and may be in the form of Marknet strip cards or smart (or IC) cards. In the former case, credit card information is magnetized and recorded, and in the latter case, it is stored in a memory. In addition, with the advent of computers and the era of electronic commerce, it is possible to consider not only physical media but also electronic credit card media.

The user computer 15 is a computer of a person who wants to receive credit transactions and other network services using the credit card 16 provided from the server computer 12. The server computer 12 and the user computers 15 are connected via a communication network 11 to communicate with each other. The user computers 15 connected to the communication network 11 are Internet browsers (eg, Netscape, Internet Explorer) capable of displaying web content in the form of Hyper Text Markup Language (HTML) or Hyper Device Markup Language (HDML). I have got Here, the user computer is not limited to a general personal computer but is used as a generic term for a terminal that can communicate with the server computer 12 through a communication network, and includes a mobile communication terminal having an internet connection function. The communication network 11 includes not only the Internet but also a general public telephone network and a mobile communication network.

The user computer 15 converts the code information 16a displayed on the credit card 16 into computer readable data through the image device 17, and then decodes the original information by using the decoding software 15c. Restore to.

Here, the image device 17 is an optical device capable of acquiring visual information from a physical object using light, and corresponds to a PC camera, a digital camera, and a scanner. The user computer 15 receives the code image 16a by the image device 17 and stores it in a memory, a hard disk, a buffer, or a screen. On the other hand, if the code image is represented electronically (for example, in the form of an image file), the image may be captured to generate the code image.

FIG. 3 is a code conversion table used for the encoding and decoding algorithm, and is a diagram illustrating an example of a code conversion table for converting various characters (alphabet, special characters, etc.), numbers, shapes, and the like into code images. As an encoding method, various characters and the like are converted into codes, and then code images are generated with colors (colors) assigned to each code. In this example, code images are generated using eight colors, and two consecutive cells are used to represent one letter or number. For each color, codes "000" through "111" are assigned. For example, the number 3 is assigned to the code " 000 011 " and encoded into the color assigned to the code " 000 " and the color assigned to the code " 011 ", and imaged into a cell of the two colors. 3 is shown in black and white gray level due to the limitation of drawing, it is also possible to use the black and white gray level in actual application, but it would be more advantageous to code recognition to implement with a combination of color colors, the number of colors It will depend on the capabilities of your color-printing device (e.g. printer) or your color-aware device (e.g. scanner).

According to the conversion table shown in FIG. 3, various characters or numbers included in the code information are coded, and then the color corresponding to the code may be expressed in the form of a rectangular matrix composed of a combination of square cells. It can also be expressed in a form. In addition, the code table may be coded in consideration of a gap between the cell (line) and the cell (line), and the code may be coded in such a manner that the square cell and the line-shaped line are combined with each other. By providing an encoding algorithm that can be encoded using various physical expression methods, it is possible to give flexibility to expression of richer characters (for example, Korean or English alphabets as well as Chinese characters or Japanese).

The color matrix image, which is one example of the code images, may include a data region in which actual code information is encoded and a reference region composed of reference cells used as reference colors in a decoding process. Here, the reference area is used to set a reference color for recognizing the color expressed in the data area. The color may be printed differently according to the type of printing or the material of the printing paper, and the same color may be recognized somewhat differently according to the characteristics of the scanner or the camera. In view of this point, the reference cell in the reference area provides a criterion for determining the color displayed in the data area. That is, the color displayed in the cells of the data area is to have a relative color tone difference compared with the reference color of the reference area. Therefore, even if the image input apparatus or the output apparatus is changed, the color tone difference between the reference region and the data region is constant, so that the color of the cell represented in the data region can be accurately recognized. This allows decoding to more reliable code information. In addition, the color matrix image may further include a parity cell in addition to the data cell. In this case, the parity is used to check an error of the original digital code data represented by the image. For example, the bit value of the digital data included in the row (column) at the end of one row and / or the end of one column is used. It can be displayed as a cell having a specific color depending on whether the number of bits "1" is odd or even.

The number of cells included in the color matrix image can be appropriately determined in consideration of the number of code information, etc. The structure is preferably NxM sized matrix type, but considering the needs of the user or the characteristics of the medium in which the code image is expressed. It can be expressed in any shape such as round or oval and can be displayed in a plurality of positions. The cells included in the color matrix code image may be formed only by the combination of colors, but may further include a line-like pattern inside each color cell.

Specifically, a method of converting information into a code image by encoding software is as follows. One or more letters or numbers included in the code information is converted by a predetermined code conversion table as shown in FIG. 3 to form a predetermined shape, color, pattern, or a combination thereof (including letters and numbers). Is converted to. Here, the code conversion table refers to a table that defines a relationship for mapping various letters, numbers, symbols, and the like into predetermined colors. Examples thereof include not only the example shown in FIG. 3, but also codes such as a barcode or PDF-417, and a matrix image composed of one-dimensional or two-dimensional monochrome or color cells (or lines). The code image may be printed in a visual form on a credit card or in the form of computer-readable file data on an electronic medium. When the code image 16a is decoded by a code conversion table, the code image may be expressed in letters and numbers. The original "code information" can be obtained.

2 is a diagram showing an example of a credit card 16 issued to a user in a server. In this example, a credit card having a shape and size similar to a business card is taken as an example, but the shape and size may be variously applied according to a use state, and may also be provided as an electronic file. The code image displayed on the credit card can be imaged in a matrix color code, and the size, number and position of cells can be arbitrarily adjusted as necessary. In addition, an internal line pattern of "+" and "x" type may be further included in each cell of the matrix type color code displayed in a barcode form.

In addition, the credit card may further include a character information unit in which the code information assigned to the user is displayed in the form of recognizable characters or symbols, and the credit information of the credit card number, the user name, and the expiration date is stored on the smart chip or the magnetic tape. It may be stored in a storage medium such as or recorded in the form of a barcode or code image.

4A is a diagram showing an example of contents stored in the user database 12a of the server 12. The user's name, postal address, zip code, nationality, as well as a homepage, an e-mail address, a phone number, a fax number, and the like are shown in FIG. Personal information is stored. In addition, index information that may refer to each personal information may be added.

4B illustrates that code information, a user ID, a password, a cumulative service score, a server address, and the like may be included as an example of information displayed as a code image, and all or some of them may be selectively set for each user. If index information for code information and / or server address information is set, the code information may be generated by encoding the index information (index encoding method). In addition to the code information, server address information (authentication server address and service server address) may be added.

"Authentication server address" refers to the network address of the server where the code database in which the code information of the user is stored is located. Basically, it is common to have a code database on a server 12 that provides credit card services (in this case, the server computer 12 becomes an authentication server and does not need to add an authentication server address), but A separate server may be provided to store a code database for code information of users. For example, a registration server may be provided to subscribers of a specific service provider, and the authentication server may separately manage code information of registered users at the company or service provider. In this case, code information may be provided. In addition, authentication server address must be included in order to receive authentication service online. In other words, the authentication database 12a shown in FIG. 1 may be configured centrally in one server, but may be distributed in multiple servers.

"Service server address" refers to the network address of a server providing a service by credit card. For example, in the case of a credit card for an "Internet phone" service, a user requests issuance of a credit card for the service with an authentication server, and the authentication server is a service server address related to the service together with the user's code information. The information in is also provided as a code image. The user accesses the authentication server with the card displaying the code image and when the authentication process is completed, the user can use the "Internet phone" service immediately.

Meanwhile, "service information" that designates a specific network service that a user wants to receive through an authentication process may be added. In this case, the credit card is directly linked to a specific service. Here, the service information is information for defining a service that can be provided by the service server. When using the Internet service, there are services defined by the protocol indicated in the URL such as web service, telnet service, e-mail service, gopher service, and FTP (File Transfer Protocol). If the service information is not included as a result of decoding, the service set as the default in the program is provided or the user selects the service separately. On the other hand, the service information includes not only for network service through the Internet but also for services defined in other general communication devices, for example, a telephone or a fax service.

4C is a diagram illustrating an example of contents stored in the code database 12b. Code information and server address information assigned to each user are stored, and index information may be added to refer to each information. Unique code information may be provided for each user, or different code information may be provided for each service for the same user.

5 is a flowchart illustrating a process of providing a credit card to a user according to the present invention. First, a user who wants to receive a service according to the present invention connects to the server 12 and applies for user registration (51). At this time, the user enters his or her personal information (for example, user name, e-mail address, postal address, postal code, nationality, homepage address, telephone number, fax number, etc.). The server 12 stores these personal information in the user database 12a.

The server 12 assigns 53 credit card information and code information to each user and stores them in the code database 12b. If the code information is stored in an authentication server other than the server 12, the server 12 transmits the code information of the user to the corresponding server for the code and stores the address of the authentication server. If the service server providing the service by user authentication is set separately from the server 12, the server 12 also stores the address of the service server.

Code information given by the server 12 is preferably encrypted by an encryption algorithm. On the other hand, server address information should not be encrypted because it must be directly available to the user's computer or server. As a method of encryption, a method of changing the order of characters or replacing other characters with a predetermined algorithm by a predetermined algorithm, or changing the amount and type of information by using a hash algorithm can be used.

Code information (if code information is encrypted, if code information is encrypted), server address information, and the like are encoded into a code image by a predetermined code conversion table (see FIG. 3) (55). Although the encryption process for the code information may be performed before encoding the information, the encryption process may be performed after the code information is encoded. In this case, the encryption method may change or replace the order of shapes, characters, patterns, colors, etc., displayed in the code image.

The encoding method may be divided into a direct encoding method and an index encoding method. The direct encoding method refers to a method of generating a code image by directly encoding code information by a code conversion table. The index encoding method is a method of encoding the index information (for example, the address or record number of the database) for referencing the authentication database 12b of the server where the code information is stored by using a code conversion table to convert the image into a form of an image. The encoded images can be automatically output by the program's algorithms, or they can be created by a graphic editor or by hand, depending on the code conversion scheme.

The server 12 displays the code image as well as the credit card information on the credit card and issues it to the user (57). The credit card information includes information such as bank name, card number, expiration date, and user name. Code images can be issued either printed or attached to a tangible object, such as a card, and can also be displayed in a computer-readable state (e.g., directly displayed on a monitor screen or read by an image editing program). File).

A brief description of the actual application state of the credit card service system as described above is as follows. When a user applies for registration with the server, the server allocates unique code information to each user and issues the code image encoded with the predetermined encoding algorithm on the credit card with the credit card information. In the authentication process for the user to receive the service provided by the server, the user inputs the code image displayed on his credit card using the image device and transmits it to the server (or, the user decodes the code image and extracts the information. May be sent to the server). The server performs a user authentication procedure according to the information transmitted from the user, determines whether the user is a legitimate user, and then provides a service. When payment of a fee (usage fee) is required in providing a service, payment is performed using credit card information.

6 is a flowchart illustrating a method for servicing using a credit card according to the present invention.

The user connects his computer 15 to the server computer 12 to start the authentication procedure. At this time, the server usually receives a user ID and password from the user and checks whether the user is registered in the authentication server. The user inputs the code image 16a displayed on his credit card 16 into the user computer 15 through the image device 17 (61). The user computer 15 may receive a code image in real time using the image device 17 or may load an image file that has already been created into a memory through a storage device such as a disk or a buffer.

The user computer 15 decodes the code image by the decoding program installed in advance and extracts the code information and the server address information (62). An example of the information extracted here is shown in FIG. 4B and is information consisting of letters, numbers, and figures. It is optional for the user computer 15 to install the decoding program in advance. If the decoding program is not installed in the user computer 15, the user computer 15 transmits the code image to the server computer 12. The decoding process is performed at the server computer 12.

Here, decoding means finding the original information from the code image as defined in the code conversion table. Decoding methods include a direct decoding method and an index decoding method according to a method of encoding information. In the direct decoding method, when the code image is decoded, actual information such as code information or server address is immediately extracted. In the index decoding method, the decoded result has index information, which is a key value for accessing a code database in which actual information such as code information or a server address is stored.

In the decoding process, it is necessary to find meaningful shapes, colors, patterns, and characters included in the code image. In addition, a process of correcting the distorted image is required. Here, using at least one method of RGB (Red, Green, Blue) model, HSV (Hue angle, Saturation, Value) model, CMY (Cyan, Magenta, Yellow) model, HLS (Hue angle, Lightness, Saturation) model Color discrimination is possible. Border and detection and thinning algorithms can also be used to detect shapes and patterns.

As a result of the decoding, it is determined whether the authentication server address is included in the decoded information. As described above, the information encoded in the code image may include not only the code information but also address information of the authentication server provided for the authentication process separately from the basic server. If the authentication server address is detected, it connects to the designated authentication server according to the information.

If the code information is generated by encrypting the code information, the authentication server (or the basic server) decrypts the encrypted code information and restores the original information, and then determines whether the user is a legitimate user from the code information.

When the verification of the code information is completed, the code database is searched to detect data related to the code information (63). As described above, when the user authentication procedure is completed and connected to the service server, the user may receive the desired service (64). The services provided may be network access services, advertising and event information services, personal information services, e-commerce services, financial services, authentication services, and the like.

When the user needs to pay for the service to be provided (65), the user may pay using the credit card information of the credit card (66). Payment methods include sending credit card information using a credit card terminal, or simply entering a credit card number (and additional password, expiration date, card owner, etc.). have. In this embodiment, it is possible to confirm whether or not the true owner of the credit card by inputting a code image in addition to inputting the credit card information. That is, when an electronic commerce or a paid service is provided through the Internet using a computer, it is usually difficult for each individual to have a credit card terminal, so that the payment is usually performed by inputting a credit card number. In this case, there is no way to prevent the illegal use of another person's credit card number. According to the present embodiment, when a code image displayed on a credit card is transmitted to a server by using a scanner or a digital camera provided in a personal computer, it is checked whether or not the code information by the code image corresponds to the credit card information. You can check whether or not you are a user. If the service server cannot perform this authentication procedure, it can connect to the server that issued the credit card and perform the process.

In the case of an e-commerce service, a transaction is established only if the number and expiration date of the credit card are known in the related art, and thus, a case in which one's own card number and expiration date is exposed to others is frequently used. However, by assigning a code image to a credit card and performing a user verification procedure using the code image, only a person possessing a credit card can make a transaction, thereby ensuring a safer transaction.

In addition, a variety of information may be provided using a code image or code information that is physically or electronically represented on a credit card. That is, when the code image is scanned, photographed by a camera, or input as a graphic image, the code information is extracted by a decoding algorithm. Alternatively, the user can directly enter the code information itself. Then, the code information is searched by accessing a database that maintains data about the code information, and the user is provided with information set in the database in relation to the code information. In addition, the server can determine the location of the user by using the location information or computer address of the terminal, the user entered the data, and access the service content (for example, the location of the credit card merchant or service of the credit card merchant) Kind etc.).

The invention can also be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, hard disk, floppy disk, flash memory, optical data storage device, and also carrier waves (for example, transmission over the Internet). It also includes the implementation in the form of. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

As described above, according to the present invention, the code information provided to the user is encoded by an encoding algorithm, converted into a physically expressed code image, and the code image is displayed on a credit card. Thus, in the authentication process during electronic commerce, a code image input through an image device such as a camera or a scanner, together with a credit card number normally input by a keyboard, can be used for user authentication, thereby ensuring a secure credit transaction.

In addition, merchants affiliated with a credit card can provide information such as events or use a personal information management system associated with the credit card. In order to receive an e-commerce service, a code image may be used as a means of accessing the service, and the credit card information such as a credit card number may be directly used through a credit card terminal or used for payment.

Code images should be limited to low level secret information such as mileage scores and cyber coin checks. In the case of depositing or withdrawing money or conducting electronic commerce using an electronic financial service, a code image may be used as an additional security means together with credit card information. In other words, by requesting a credit card number in the payment step and additionally requesting input of a code image or code information, even if the credit card number is known, payment is not made unless the code information is known or the code image is not obtained. In this case, even though the code image is not necessarily displayed on the credit card, it may be displayed and provided on a separate medium, and a special encryption system may be provided. As an example, a method of differently setting code information to be input for each date may be used.

In the case of a mobile terminal, the location of the user can be determined by the cell of the GIS and the GPS or the cellular phone. If you access the server using the code image, you can provide credit card merchants, affiliate service information, and geographic information in a map format and use related services such as reservation and navigation.

Claims (14)

Applying for user registration with a server; Assigning credit card information and code information to a user and storing the same; Converting the code information into a code image that is physically or electronically encoded by encoding the code information by a predetermined encoding algorithm; Displaying the credit card information on the credit card medium together with the code image; And Providing the credit card medium to the user. The method of claim 1, wherein the code image An image having a predetermined shape, color, pattern, or a combination thereof generated by converting one or more letters or numbers included in the code information by a predetermined code conversion table for mapping each letter and number to a predetermined color, respectively. Credit card providing method characterized in that. 2. The credit card of claim 1, wherein the code information assigning step sets a network address of a code server in which the code information is stored, and encodes the code information and a network address of the code server in the encoding step. How to Provide. The method of claim 1, wherein the step of allocating the code information sets a network address of a service server to provide a service by authenticating a user according to the code information, and in the encoding step, combines the code information and the network address of the service server. Credit card providing method characterized in that the encoding. In the credit transaction method of receiving and paying for electronic commerce or paid service through a communication network, Inputting information related to a credit transaction including a credit card number; Inputting a coded image represented physically or electronically into a credit card; Extracting code information of a user from the input code image by a predetermined decoding algorithm; Comparing whether the extracted code information is identical with code information set in relation to the credit transaction information, and determining whether the user is a valid credit card holder; And And establishing a credit card transaction if it is determined that the user is a legitimate user. The method of claim 5, wherein the code image is An image having a predetermined shape, color, pattern, or a combination thereof generated by converting one or more letters or numbers included in the code information by a predetermined code conversion table for mapping each letter and number to a predetermined color, respectively. Credit transaction method characterized in that. Allocating credit information and related code information to each user, encoding the code information by an encoding algorithm, converting the code information into a code image that can be expressed physically or electronically, and displaying it on a credit card to provide to the user. Credit card provider; A storage unit having a code database storing credit transaction information issued to a user and code information related thereto; Receives credit information from the user, receives the code image displayed on the user's credit card, decodes it by a decoding algorithm, extracts the code information embedded in the code image, and sets a code related to the credit transaction information input by the user. And a judging unit comparing the extracted information with the extracted code information to determine whether the holder is a legitimate credit card holder. The method of claim 7, wherein the code image is An image having a predetermined shape, color, pattern, or a combination thereof generated by converting one or more letters or numbers included in the code information by a predetermined code conversion table for mapping each letter and number to a predetermined color, respectively. Authentication service device, characterized in that. In the credit transaction method of receiving and paying for electronic commerce or paid service through a communication network, Inputting information related to a credit transaction including a credit card number; Inputting a coded image represented physically or electronically into a credit card; Extracting code information of a user from the input code image by a predetermined decoding algorithm; Comparing whether the extracted code information is identical with code information set in relation to the credit transaction information, and determining whether the user is a valid credit card holder; And And a step of establishing a credit card transaction if it is determined that the user is a legitimate user in the determining step. Tangible media having a physical shape; A code information unit in which code information assigned to a user is encoded by a predetermined encoding algorithm and converted into a physical code image on the surface of the medium; And A credit card medium comprising a credit information book that holds information required for a user's credit transaction. The credit card medium according to claim 10, further comprising a character information unit in which code information assigned to a user is displayed in the form of recognizable characters or symbols. The credit card of claim 10, wherein the credit card information is stored in a storage medium such as a smart chip or a magnetic tape or recorded in the form of a barcode or a code image. media. Inputting a code image expressed physically or electronically into a credit card or directly inputting code information; Extracting code information of a user by a predetermined decoding algorithm when a code image is input in an adding step; Retrieving the code information by accessing a database that holds data about the extracted code information; And providing the user with information set in the database in relation to the code information. The method of claim 13, further comprising: determining a location of a user using location information or a computer address of the input terminal; And And providing service content accessible in relation to the user's location.