Payment application program, terminal device, and display control method

Abstract

This invention provides a payment application program, terminal device, and display control method that improve the usability of payment applications installed on user terminals in electronic payment services. [Solution] The payment application 300 stored in the memory unit 204 is executed by installing it on a user terminal used by an electronic payment user in order to use electronic payment using an identification code. The user terminal on which the payment application is installed has the functions of a posture detection unit 302 that detects the posture of the user terminal and a display control unit 303 that controls the display on the display unit of the user terminal. The display control unit 303 has the function of switching the display state of the display unit when the posture of the user terminal detected by the posture detection unit 302 changes to a first posture suitable for reading the identification code by a mounted code reader.

Description

[Technical Field] 【0001】 This disclosure relates to a payment application program, terminal device, and display control method. [Background technology] 【0002】 Cashless payment, which allows for payment without the use of money for goods or services, is becoming increasingly popular. In particular, electronic payment using payment application programs that can be installed on terminal devices such as smartphones (hereinafter referred to as payment apps) is attracting attention due to its high level of convenience. There are two methods of payment using payment apps. The first method involves displaying a user identification code (barcode or QR code®) containing the user's identification information on the user's terminal device, and having store staff read it using a code reader on the store's terminal. The second method involves scanning a store identification code displayed in the store with the user's terminal and entering the payment amount. 【0003】 Patent Document 1 describes an example of a screen used in the first method. Specifically, it describes that when a predetermined button on a screen displaying buttons related to various services, which is shown on the user's terminal after the payment application is launched, is operated, the user transitions to a different payment screen, and a user identification code is enlarged and displayed on the payment screen. Patent Document 2 also describes an example in the second method in which a scan screen used to read a store code is displayed on the user's terminal, and then the user transitions to an amount input screen. [Prior art documents] [Patent Documents] 【0004】 [Patent Document 1] Japanese Patent Publication No. 2023-127458 [Patent Document 2] Patent No. 7105337 [Overview of the project] [Problems that the invention aims to solve] 【0005】 However, the technology described in the patent documents has room for improvement in terms of the usability of the payment application. 【0006】 This disclosure aims to improve the usability of payment applications installed on users' terminal devices in electronic payment services. [Means for solving the problem] 【0007】 A payment application program according to one aspect of the present disclosure is a payment application program installed on a terminal device used by a user of electronic payment to use electronic payment using an identification code, wherein the terminal device functions as a detection unit for detecting the orientation of the terminal device and a display control unit for controlling the display on the display unit of the terminal device, and the display control unit switches the display state of the display unit when the orientation of the terminal device detected by the detection unit changes to a first orientation suitable for reading the identification code by a mounted code reader. [Effects of the Invention] 【0008】 According to this disclosure, it is possible to improve the usability of payment applications installed on users' terminal devices in electronic payment services. [Brief explanation of the drawing] 【0009】 [Figure 1] This is a diagram showing an example of the system configuration of an electronic payment system. [Figure 2] Block diagram showing an example of a user terminal hardware configuration. [Figure 3] This figure shows an example of the software configuration of a user terminal. [Figure 4] This diagram shows the orientation of the user's terminal when reading a code using a mounted code reader. [Figure 5] This diagram illustrates the coordinate system of the user's terminal. [Figure 6] It is a diagram for explaining rotation about the longitudinal axis of the user terminal. [Figure 7] It is a diagram for explaining the inclination of the longitudinal axis of the user terminal from the gravitational direction. [Figure 8] It is a flowchart showing the flow of display control processing in the first embodiment. [Figure 9] It is a diagram showing an example of the top screen in the normal state. [Figure 10] It is a diagram showing an example of the code expansion screen in the first embodiment. [Figure 11] It is a diagram showing a first modification example of the code expansion screen. [Figure 12] It is a diagram showing a second modification example of the code expansion screen. [Figure 13] It is a diagram showing an example of a payment screen which is a third modification example of the code expansion screen. [Figure 14] It is a diagram showing a state where a message area is superimposed on the code expansion screen of FIG. 13. [Figure 15] It is an example of the top screen in the second embodiment with stealth display. [Figure 16] It is a diagram showing a state where a message area is superimposed on the screen of FIG. 16. [Figure 17] It is a flowchart showing the flow of display control processing in the second embodiment. [Figure 18] It is a flowchart showing the flow of stealth display processing in the second embodiment. [Figure 19] It is a diagram showing an example of the top screen in the third embodiment in the fade-out state. [Figure 20] It is a flowchart showing the flow of fade-out display processing in the third embodiment. [Figure 21] It is a flowchart showing the flow of setting processing in the fourth embodiment. [Figure 22] It is a diagram showing an example of the setting screen in the turnover mode. 【Modes for Carrying Out the Invention】 【0010】 Preferred embodiments of the payment application program, terminal device, and display control method relating to this disclosure will be described in detail below with reference to the drawings. However, these embodiments do not limit the payment application program, terminal device, and display control method relating to this disclosure. Furthermore, identical components are denoted by the same reference numerals in the following embodiments, and redundant descriptions are omitted. In this specification, the payment application program is referred to as a payment app. 【0011】 A payment application according to one aspect of this disclosure is a payment application installed on a terminal device used by an electronic payment user to make electronic payments using an identification code. The payment application causes the terminal device to function as a detection unit that detects changes in the orientation of the terminal device, and a display control unit that controls the display on the display unit of the terminal device. The display control unit switches the display state of the display unit when the orientation of the terminal device detected by the detection unit changes to a first orientation (reading orientation) suitable for reading the identification code by a mounted code reader. 【0012】 According to this disclosure, when a user changes the orientation of the terminal device to a first orientation (reading orientation) suitable for reading identification codes with a mounted code reader, the display can be switched, for example, from the top screen to a code enlargement screen. The first orientation (reading orientation) is the orientation in which the display screen of the terminal device is facing the reading surface of the mounted code reader. The mounted code reader, the first orientation (reading orientation), and examples of display switching will be described later. 【0013】 Conventionally, when an identification code displayed on a user's terminal is to be read by a stationary code reader, the user must first launch the payment app, display the top screen, and operate the payment button displayed on the top screen to transition to the payment screen where the identification code is enlarged. Then, the user holds the payment screen over the code reader. Alternatively, the user can hold the top screen, which still displays the identification code in small print, over the code reader. In the former case, operation of the payment button was necessary. Also, on the top screen, which displays a lot of information, it was sometimes difficult to quickly find where the payment button was displayed, causing delays in operation. In the latter case, due to the limitations of the screen layout, the identification code was displayed in small print, which sometimes prevented smooth reading by the code reader. However, with the payment app disclosed herein, simply by the user positioning their terminal over the stationary code reader, the system can switch to an appropriate display, such as enlarging the identification code. Therefore, the system can switch to a display state suitable for code scanning by a stationary code reader without any operational hassle, enabling smooth reading by the stationary code reader. Therefore, compared to conventional methods, the usability of payment applications in payment processing using mounted code readers is improved. 【0014】 Furthermore, it is preferable that such display control based on changes in the user's terminal orientation be performed after the payment application has been launched. For example, it is preferable that this be performed on the top screen of the payment application. 【0015】 <First Embodiment> (Overview of the electronic payment system) This document outlines an electronic payment system using the payment application related to this disclosure. Figure 1 shows an example of the system configuration of electronic payment system 1. As shown in Figure 1, electronic payment system 1 includes a user terminal 2, a store terminal 3, and an electronic payment server 5. The store terminal 3 and the electronic payment server 5 are connected to each other via network 4. In addition, the user terminal 2 and the electronic payment server 5 are connected to each other via network 4. 【0016】 As will be explained in more detail later, there are two payment methods using payment apps. The first method involves having the store's terminal's code reader read a user identification code, which contains the user's identification information. The second method involves scanning a store identification code, which contains the store's identification information, displayed in the store, with the user's terminal and then entering the payment amount. In the following explanation, the first method will be referred to as store scan, and the second method as user scan. 【0017】 In this specification, a user is defined as a person who makes a payment for goods or services at a store using a payment application. The user obtains an account for the electronic payment service provided by the electronic payment system 1, for example, using the account management function of the payment application. The user's account is managed by the electronic payment server 5 and is linked to the user's identification information and electronic account. The user can access the electronic payment service by installing the payment application on the user terminal 2. The electronic payment service can also be accessed by using a general web browser to access the website provided by the electronic payment server 5. 【0018】 (Store terminal) The store terminal 3 is an information processing device used by stores that have a contract with a service provider that provides electronic payment services, or by service providers that provide such services. The store terminal 3 consists of at least a computer having a product price acquisition function, an optical reading function, a program execution function, and a communication function. The store terminal 3 includes a so-called POS (Point of Sale) device, and the product price acquisition function and optical reading function may be implemented by the POS device. The optical reading function is implemented by a code reader such as a barcode reader that reads images of one-dimensional codes such as barcodes, or a camera that reads images of two-dimensional codes such as QR codes. Hereinafter, barcode readers and code readers together will be referred to as code readers 31. Code readers 31 are broadly classified into handheld and stationary types, but in this embodiment, a stationary type will be used. The stationary code reader 31 will be described later. In addition, a store code image 32 may be displayed in the store. The store code image 32 shows the store URL, which is the store's identification information, in the form of a two-dimensional code such as a QR code. The store code image 32 may be printed on paper or plastic media and displayed, or it may be displayed on a screen. Hereinafter, stores or service providers that have a contract with a service provider that provides electronic payment services will be referred to as "merchants." Merchants include, for example, organizations that operate multiple physical stores or online shops. "Store" means any place that actually provides goods or services to users, such as shops, restaurants, department stores, movie theaters, or gyms. "Goods" means tangible items such as goods that users actually acquire at a store, or intangible items such as image data, video data, music data, and game programs. "Services" means services that users actually receive at a store, etc. 【0019】 (Electronic payment server) The electronic payment server 5 is an information processing device that provides electronic payment services, including electronic payment processing and distribution of information related to electronic payments. It consists of at least a computer having communication and program execution functions. The electronic payment server 5 manages the electronic accounts of merchant stores and the electronic accounts of users who have accounts for the electronic payment service. It enables various payments, for example, by transferring electronic money between electronic accounts. The electronic payment server 5 may be implemented by a single information processing device or by multiple information processing devices. 【0020】 (User terminal) User terminal 2 is a terminal device used when a user makes an electronic payment at a merchant. For example, a portable terminal device such as a smartphone is commonly used. The payment app 300 is pre-installed on user terminal 2 when a user makes an electronic payment. The payment app 300 is operated and managed by the service provider that provides the electronic payment service. The payment app 300 will be described later. As mentioned above, there are two main methods for making an electronic payment at a merchant using the payment app 300: store scan and user scan. 【0021】 (Store scan) In store scanning, the store terminal 3 optically reads the user's identification code displayed on the user terminal 2 using a code reader 31, decodes the read identification code to obtain the user's identification information. The store terminal 3 sends the obtained user identification information along with a payment request to the electronic payment server 5. The electronic payment server 5 generates a one-time code in response to the payment request and returns it to the store terminal 3. The store terminal 3 adds the store's identification information and payment amount information to the received one-time code and sends it to the electronic payment server 5. Based on the information received from the store terminal 3, the electronic payment server 5 identifies the user's and store's electronic accounts from its database and performs the payment processing. Once the payment processing is complete, the electronic payment server 5 displays a payment completion screen on the user terminal 2. The store terminal 3 may send and receive payment-related information directly with the electronic payment server 5, or it may send and receive payment-related information via the server of an intermediate payment service provider. 【0022】 When a user presents an identification code to store staff during a store scan, the user may present the identification code displayed on the top screen of the payment app 300, or the identification code displayed on a separate payment screen. The top screen and the payment screen display a first identification code and a second identification code, which are user codes that encode the user's identification information. The first identification code is a one-dimensional code such as a barcode, and the second identification code is a two-dimensional code such as a QR code (registered trademark). As will be explained in more detail later, the top screen also displays information such as the balance of the electronic account, points information, account information, and credit information, in addition to the identification code. 【0023】 (User scan) In the user scan, the user terminal 2 reads a store code image 32, such as a QR code, displayed in the store. The store code image 32 contains information about the store's URL. The payment application 300 on the user terminal 2 adds the user's identification information to the read store URL information and sends it to the electronic payment server 5. The electronic payment server 5 identifies the user and store from its database based on the received store URL and user identification information, and displays an amount input screen on the user terminal 2. The user terminal 2 accepts the amount input from the user on the amount input screen and sends the entered amount information to the electronic payment server 5. The electronic payment server 5 processes the payment between the identified user and store's electronic accounts. Once the payment processing is complete, a payment completion screen is displayed on the user terminal 2. 【0024】 For reading the store code image 32 during user scanning, a scan screen, separate from the top screen, is used. The user operates the payment app 300 to display the scan screen on the display unit 206 of the user terminal 2 and takes a picture of the store code image 32. The user can access the scan screen by tapping the scan button displayed on the top screen or by tapping a specific button displayed on the payment screen. 【0025】 (Hardware configuration of user terminals) Figure 2 shows the hardware configuration of the user terminal 2 according to this embodiment. As an example of the user terminal 2, an example of the internal configuration of a smartphone is shown. In this embodiment, the user terminal 2 is described using a smartphone as an example, but is not limited to this. The user terminal 2 may be, for example, a tablet device, a notebook PC (Personal Computer), a desktop PC, or a PDA (Personal Digital Assistant), etc. 【0026】 The user terminal 2 is equipped with a CPU 201, ROM 202, RAM 203, storage unit 204, operation unit 205, communication interface 208, camera 209, voice processing unit 210, acceleration sensor 212, and gyro sensor 213, and each unit is connected via a bus 214. The operation unit 205 has a display unit 206 and an input unit 207. 【0027】 The CPU 201 is the central processing unit and controls various parts of the user terminal 2. The CPU 201 reads programs stored in the ROM 202 or memory unit 204 into the RAM 203 and executes the read programs to realize the various functions contained in the programs. The CPU 201 may be an MPU (Micro Processing Unit) or an ASIC (application specific integrated circuit). The CPU 201 may also be an FPGA (Field Programmable Gate Array), etc. The CPU 201 may consist of one processor or multiple processors. 【0028】 ROM202 stores the startup program and OS (Operating System) of user terminal 2. RAM203 temporarily stores programs or data when the CPU201 executes various processes. RAM203 is used as work memory. 【0029】 The storage unit 204 is memory for storing application programs and various data. Examples of storage units 204 include HDDs (Hard Disk Drives), SSDs (Solid State Drives), flash memory, and storage devices. 【0030】 The operation unit 205 is a user interface that receives operations from the user, inputs the received operation information to the CPU 201, and outputs the output information from the CPU 201 in a way that the user can recognize. In each embodiment of this disclosure, the operation unit 205 is assumed to be a touch panel display in which the display unit 206 and the input unit 207 are integrally configured. The display unit 206 includes a display and a display control circuit, and displays various screens on the display based on the output information input from the CPU 201. The screens that are displayed will be described later. The input unit 207 includes input devices such as various buttons and a touch panel, and transmits information input by the user via the input devices to the CPU 201. Note that the operation unit 205 does not necessarily have to have the display unit 206 and the input unit 207 integrally configured, and they may be configured separately. Also, the operation unit 205 may be provided separately from the main body of the user terminal 2 and connected wirelessly or by wire. 【0031】 Communication I / F208 includes an interface for communication connection with network 4, including LAN (Local Area Network), WAN (Wide Area Network), the Internet, and mobile communication networks, as well as interfaces for short-range wireless communication such as Bluetooth® and NFC (Near Field Communication). Communication I / F208 can be wired or wireless. User terminal 2 receives data etc. from other devices via communication I / F208 and transmits data etc. generated or stored by user terminal 2 to other devices via communication I / F208. 【0032】 Camera 209 has an optical system including a lens and an image sensor such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) sensor, and outputs the captured image data to CPU 201. The code reading function of the payment application 300 is implemented using camera 209. 【0033】 The audio processing unit 210 includes a microphone and a speaker. The microphone acquires the voice of users, store staff, etc., and outputs it as audio data to the CPU 201. The speaker outputs the audio data input from the CPU 201 so that users can listen to it. 【0034】 The acceleration sensor 212 measures the acceleration of each axis (X axis, Y axis, Z axis) of the user terminal 2 and estimates the tilt angle from the direction of gravity. For example, if the longitudinal direction of the user terminal 2 is the Y axis, when the user holds the user terminal 2 vertically, the gravitational acceleration in the Y axis direction is 9.8 [m / s²]. 2 The following is at work: When the user holds the user terminal 2 horizontally, the gravitational acceleration in the Y-axis direction becomes 0. When the user terminal 2 is tilted, the acceleration sensor 212 detects the direction of the gravity vector and detects the amount of change as the amount of tilt from the direction of gravity. The acceleration sensor 212 outputs the detected value to the CPU 201. 【0035】 The gyro sensor 213 is a vibration-type gyro sensor or a capacitive-type gyro sensor, and measures the rotation of the user terminal 2. While the accelerometer 212 senses static tilt, the gyro sensor 213 detects the movement and rotation of the user terminal 2. The gyro sensor 213 tracks changes in rotation angle with the X, Y, and Z axes of the user terminal 2 as the centers of rotation. The gyro sensor 213 outputs the detected values ​​to the CPU 201. 【0036】 Note that the user terminal 2 is not limited to the configuration shown in Figure 2. For example, it may be equipped with a geomagnetic sensor for measuring the magnitude and direction of the magnetic field, or a positioning unit for implementing GPS functionality. The user terminal 2 may also be equipped with a media I / F (not shown). The media I / F is an interface for connecting a media drive device that reads and writes data and programs stored on a data storage medium (hereinafter referred to as "media") connected by wire or wireless. The media I / F reads programs and data stored on the media, temporarily stores them in RAM 203, and inputs them to CPU 201. CPU 201 can load the input program into the work memory of RAM 203 and execute processing. The media includes, for example, optical recording media such as DVD (Digital Versatile Disc) and PD (Phase change rewritable Disk), magneto-optical recording media such as MO (Magneto-Optical disk), tape media, magnetic recording media, or semiconductor memory. 【0037】 The CPU 201 of the user terminal 2 implements various functions by reading programs stored in the memory unit 204, ROM 202, and media into the RAM 203 and executing them. Programs may also be obtained from other devices, such as a server, via the network 4. Furthermore, it goes without saying that the user terminal 2 is equipped with the necessary configurations to realize the information processing in this embodiment. 【0038】 (Payment application features) Next, the functions and data of the payment application 300 according to this embodiment will be described with reference to Figure 3. Figure 3 is a diagram showing an example of the software configuration of the user terminal 2. In this embodiment, the display control function of the user terminal 2 will be described in detail. 【0039】 Figure 3(a) is a diagram showing the data stored in the storage unit 204 of the user terminal 2. As shown in Figure 3(a), the storage unit 204 of the user terminal 2 stores the program of the payment application 300, data for various screens displayed in the payment application (hereinafter referred to as screen data 310), user identification information 320 for the electronic payment service, and various setting information 330 for the payment application 300. The identification information 320 is assigned by the electronic payment server 5 when the account is registered. The setting information 330 includes various setting information related to the functions of the payment application 300. For example, it stores setting information such as whether to enable or disable the turnover mode, which is an operating mode that changes the display state based on the orientation of the user terminal 2. The screen data 310 includes screen data for the top screen, payment screen, and scan screen mentioned above, as well as screen data for mini-applications included in the payment application, screen data for the amount input screen and payment completion screen displayed during payment processing, and screen data for various error notification screens. 【0040】 The payment application 300 is an application program installed and used by the user terminal 2 of an electronic payment service user, and is operated and managed by the service provider that provides the electronic payment service. While the payment application 300 is typically installed on the user terminal 2 by downloading it from a website, it may also be installed on the user terminal 2 by reading it from media. Alternatively, the payment application 300 may be provided as a web application that runs on the web browser of the user terminal 2. 【0041】 The payment app 300 has various functions in addition to payment processing functions for making electronic payments in electronic payment services. For example, it includes a money transfer function, a points function, a transaction history display function, a charge function, a coupon function, a utility bill payment function, a stamp card function, a shopping function, a finance function, an information content distribution function, a My Page function for managing user account information, and other functions. In the following description, functions other than the payment processing function in the payment app 300 are collectively referred to as mini-apps. The payment app 300 also has a display control function to control the screen display, a posture detection function to detect the posture of the user terminal 2 and changes in posture, and a setting function for setting the turnover mode, which is an operating mode that switches the display according to the posture. 【0042】 Figure 3(b) shows the configuration of the program modules of the payment application 300. As shown in Figure 3(b), the payment application 300 of this embodiment has a payment processing unit 301, a posture detection unit 302, a display control unit 303, and a setting unit 304 as program modules. Although not shown, the payment application 300 also has various program modules and data related to the mini-application. 【0043】 The payment processing unit 301 performs payment processing using an identification code with the store terminal 3 or the electronic payment server 5. The payment processing unit 301 sends and receives payment-related information between the user terminal 2 and the store terminal 3 or the electronic payment server 5 according to the processing procedures for store scan and user scan described above, and starts and completes the electronic payment. 【0044】 The posture detection unit 302 detects the posture of the user terminal 2 and changes in posture. The posture detection unit 302 acquires detection values ​​from the acceleration sensor 212 and the gyro sensor 213, and determines the posture of the user terminal 2 and the amount of change in posture based on the acquired gravity vector information and rotation angle information of the user terminal 2. The posture detection unit 302 outputs the determined posture information and the amount of change in posture information to the display control unit 303. In the following description, the posture information and the amount of change in posture information will be referred to as posture information. 【0045】 (Mounted code reader) Figure 4 shows the orientation of the user terminal when reading a code with a mounted code reader. During store scanning, the user holds the identification code displayed on the user terminal 2 over the reading surface 40 of the mounted code reader 31. In the following description, the orientation in which the display screen (front surface 2A) of the user terminal 2 is facing the reading surface 40 of the mounted code reader 31 is referred to as the reading orientation. The mounted code reader 31 shown in Figure 4 has a reading surface 40 for reading identification codes on the top surface of the main body. When reading an identification code with this top-reading type mounted code reader 31, the user positions the display screen (front surface 2A) of the user terminal 2 facing the reading surface 40. That is, the user rotates the user terminal 2 so that the front surface 2A faces the mounted code reader 31 and tilts it to an angle parallel to or nearly parallel to the reading surface 40. In Figure 4, the front surface 2A of the user terminal 2 is positioned roughly parallel to the reading surface 40, but code reading is possible even if they are not perfectly parallel. Note that the mounted code reader 31 in Figure 4 is an example in which the reading surface 40 is inclined with respect to the mounting surface 41 (horizontal plane), but it is not limited to this example. There are also types in which the reading surface 40 is provided parallel to the mounting surface 41, types in which the reading surface 40 is provided perpendicular to the mounting surface 41, and types in which the reading surface 40 is positioned opposite the mounting surface 41. For any type of mounted code reader 31, the user needs to position the display screen (front surface 2A) of the user terminal 2 facing the reading surface 40. 【0046】 (User terminal orientation) The posture of user terminal 2 will be explained. Figure 5 illustrates the coordinate system of the user terminal 2. Figure 5(a) is a perspective view of the user terminal 2, and Figure 5(b) is a side view. In Figure 5, the user terminal 2 is assumed to have a plate-like (approximately rectangular) shape with a predetermined thickness. The shape of the user terminal 2 is arbitrary and not limited to the shape shown in Figure 5. In Figure 5, X, Y, and Z are the local coordinate axes of the user terminal 2. In this specification, the longitudinal axis of the user terminal 2 is defined as the Y-axis, the thickness axis as the Z-axis, and the axis perpendicular to the Y-axis and Z-axis as the X-axis. That is, when the longitudinal axis (Y-axis) of the user terminal 2 is aligned with the vertical (direction of the gravity vector), the left-right direction of the display screen is the X-axis direction, the up-down direction of the display screen is the Y-axis direction, and the depth direction of the display screen is the Z-axis direction. Furthermore, the central point of the user terminal 2 (the midpoint of the X, Y, and Z directions) is defined as the origin 2O of the coordinate axes, the side facing the display screen is defined as the front surface 2A, and its back surface is defined as the back surface 2B. Furthermore, in Figure 5, the coordinate system of the user terminal 2 is a left-handed system. That is, with the front surface 2A facing the user and the positive direction of the Y-axis aligned with the direction of the gravity vector (vertically downward), the direction from the front surface 2A to the back surface 2B is the positive direction of the Z-axis, and the direction from right to left on the display screen is the positive direction of the X-axis. In the following explanation, the rotation angle around the X-axis is called the pitch angle θ, the rotation angle around the Y-axis is called the yaw angle ψ, and the rotation angle around the Z-axis is called the roll angle φ. The positive direction of rotation is the direction of rotation of a left-handed screw (counterclockwise when facing the positive direction of each axis). Note that the definition of the coordinate system is an example in this embodiment, and it may also be expressed in a right-handed coordinate system. Alternatively, the positive direction of rotation may be the direction of rotation of a right-handed screw (clockwise when facing the positive direction of each axis). 【0047】 Figure 6 illustrates the rotation (yaw rotation) of the user terminal 2 around its longitudinal axis (Y-axis). Figure 6(a) shows the orientation of the user terminal 2 with its display screen (front surface 2A) facing forward, and the direction from the top to the bottom of the screen being the direction of the gravity vector. In this specification, this orientation is defined as the reference orientation before rotation (θ=0, ψ=0, φ=0). Note that the reference orientation may be determined arbitrarily. 【0048】 Figure 6(b) shows the rotation operation from the reference position shown in Figure 6(a) to the opposite side (back side 2B), with the display screen (front side 2A) facing the opposite side. This operation is a rotation operation around the longitudinal axis (Y axis) of the user terminal 2. In Figure 6(b), the dashed arrow 50 shows the X axis before rotation, and the solid arrow 61 shows the X axis after rotation, rotating in the yaw direction by the rotation angle (amount of rotation) ψ shown by arrow 62. When the user is holding the user terminal 2 vertically with their left hand with the display screen (front side 2A) facing them, considering the range of motion of the wrist, it is usually rotated in the positive yaw direction as shown by arrow 62. When the user is holding the user terminal 2 vertically with their right hand with the screen facing them, it is usually rotated in the opposite direction of arrow 62 (negative yaw direction). 【0049】 Figure 6(c) is a view of Figure 6(b) in the Y-axis direction. Arrows 60, 61, and 62 in Figure 6(c) correspond to arrows 60, 61, and 62 in Figure 6(b), respectively. The dashed lines 63 and 64 indicate the yaw rotation angles ψ1 and ψ2, respectively, with respect to the X-axis 60 before rotation. 【0050】 Figure 7 illustrates the tilt (rotational motion in the pitch direction) of the longitudinal axis (Y-axis) of the user terminal 2 relative to the direction of gravity. As shown in Figure 7, the tilt angle between the Y-axis of the user terminal 2 and the gravity vector G is the rotation angle θ in the pitch direction of the user terminal 2. If we take the pitch angle where the positive direction of the Y-axis coincides with the direction of the gravity vector G as the reference for the tilt angle (θ=0), then the orientation in which the display screen (front surface 2A) of the user terminal 2 is tilted downwards until it is horizontal is θ=90°(π / 2). If the positive and negative directions of the longitudinal axis (Y-axis) of the user terminal 2 are reversed, then θ=180°(π / 2). 【0051】 In store scanning, the operation to change the user terminal 2 from a reference orientation to a reading orientation includes either or a combination of the yaw rotation operation shown in Figure 6 and the pitch rotation operation shown in Figure 7. Specifically, as with the mounted code reader 31 shown in Figure 4, if the reading surface 40 is inclined with respect to the mounting surface 41 (horizontal plane), the reading orientation can be described as an orientation that has rotated by ψs in the yaw direction and θs in the pitch direction from the reference orientation. From the viewpoint of operability, it is preferable that the reading orientation includes a certain margin, in which case the reading orientation can be described as an amount of rotation ψ in the yaw direction of ψ being ψ1 or more and less than ψ2 (ψ1≦ψ<ψ2), and an amount of rotation θ in the pitch direction of θ being θ1 or more and less than θ2 (θ1≦θ<θ2). In the following explanation, the threshold range for determining whether it is a reading orientation is α in the yaw direction and β in the pitch direction. In other words, the threshold range α for yaw rotation is ψ1 ≤ α < ψ2, and the threshold range β for pitch rotation is θ1 ≤ β < θ2. 【0052】 Specifically, when changing from the reference orientation to the reading orientation, the user rotates the user terminal 2 in the yaw direction so that the front surface 2A of the user terminal 2 changes from facing towards the user to facing away from the user. The amount of yaw rotation (amount of rotation around the longitudinal axis) ψ when changing to the opposite direction is +180° when the user terminal 2 is held with the left hand, and -180° when held with the right hand. The range in the vicinity of this (including the margin (±ψm)) becomes the threshold range α in the yaw direction. 【0053】 In other words, if ψs is the amount of yaw rotation required to achieve the appropriate reading posture, then the threshold range α is: (ψs-ψm)≦α<(ψs+ψm) It can be expressed as follows. 【0054】 If the yaw angle rotation ψs required to achieve a proper reading posture is ±180° and the margin ψm is ±10°, then the threshold range α in the yaw direction is -190°≦α<-170° and 170°≦α<190°. From the viewpoint of achieving more accurate readings, it is preferable to be as parallel as possible to the reading surface 40. In that case, it is possible to narrow the margin ψm, for example, to about ±5°. 【0055】 Furthermore, the threshold range β in the pitch direction is determined based on the inclination angle of the reading surface 40 of the mounted code reader 31. In the reading position, it is preferable that the display screen (front surface 2A) of the user terminal 2 is parallel to the reading surface 40. If the inclination angle of the reading surface 40 of the mounted code reader 31 from the mounting surface (horizontal) is λ, then the inclination angle of the reading surface 40 from the gravity vector G is (90°-λ). This angle is the reading position θs in the pitch direction. The threshold range β in the pitch direction is the threshold range that includes a predetermined margin (±θm) in addition to this reading position θs. 【0056】 The threshold range β in the pitch direction is: (90°-λ)-θm≦β<(90°-λ)+θm It can be expressed as follows. 【0057】 The rotation angle in the pitch direction is, in other words, the tilt angle relative to the direction of gravity along the longitudinal axis. For example, if the tilt angle λ of the reading surface 40 is "5°" and the margin θm is "±5°", then the threshold range β in the pitch direction is 80°≦β<90°. 【0058】 When the tilt angle λ of the reading surface 40 of the mounted code reader 31 is 0° (horizontal), the threshold range β in the pitch direction is: This can be expressed as (90°-θm)≦β<(90°+θm). If the margin θm is set to "±5°", then the threshold range β in the pitch direction is 85°≦β<95°. 【0059】 If the inclination angle λ of the reading surface 40 of the mounted code reader 31 is 90° (vertical), then the threshold range β in the pitch direction is: This can be expressed as -θm ≤ β < θm. If the margin θm is set to "±5°", then the threshold range β in the pitch direction is -5°≦β<5°. 【0060】 When the reading surface 40 of the mounted code reader 31 is positioned opposite the mounting surface 41, the case is the same as when the inclination angle λ is 0° (horizontal), but the front surface 2A is facing upward (ψ=0). 【0061】 As mentioned above, there are various types of inclination angles for the reading surface 40 of the mounted code reader 31, and users cannot freely choose one. Therefore, when determining the reading posture, it is acceptable to consider only the amount of rotation in the yaw direction and not the change in posture in the pitch direction. 【0062】 The threshold ranges α and β for determining the reading posture may also be determined by considering the range of motion of the wrist, the positional relationship between the user and the mounted code reader 31, etc. In actual stores, it is conceivable that the mounted code reader 31 may not be directly in front of the user's standing position. To account for such cases, the threshold range α in the yaw direction may be set to be wider. For example, ψ1 = ±90°, ψ2 = ±270°, etc. Also, since there is a limit to the range of motion of a person's wrist, a restriction such as |ψ2| ≤ 180° may be set. In any case, the threshold ranges α and β may be determined arbitrarily. 【0063】 Furthermore, the threshold ranges α and β may be determined statistically by aggregating the orientation of the user terminal 2 when the mounted code reader 31 performs reading. These aggregated values ​​may be collected by the electronic payment server 5, and the threshold ranges α and β may be determined by the electronic payment server 5. 【0064】 Furthermore, when the CPU 201 determines whether it is in a reading position, it may make the determination based on the amount of change in position per unit time. That is, the rotational speed or rotational acceleration of the yaw angle or pitch angle may be a predetermined threshold ψ TH , θ TH If the above conditions are met, it may be determined that there has been a change in the reading posture. In that case, the threshold is, for example, the change in yaw angle per unit time ψ.TH is 90° or more, and the change amount θ of the pitch angle per unit time TH may be set to be 90° or more. 【0065】 The CPU 201 (posture detection unit 302) calculates the posture of the user terminal 2 based on the detection values of the acceleration sensor 212 and the gyro sensor 213. Specifically, the CPU 201 detects the gravity vector G based on the detection value of the acceleration sensor 212, and determines the angle θ in the pitch direction of the user terminal 2 based on the direction of the gravity vector G. In addition, the CPU 201 tracks the rotation of each axis of the user terminal 2 by the gyro sensor 213, and further determines the change amount of the pitch angle θ with higher accuracy, and determines the rotation amount ψ of the yaw angle and the rotation amount φ of the roll angle. 【0066】 Whether the posture of the user terminal 2 is the reading posture or not is determined based on the above-described threshold ranges α, β, or the threshold ψ of the change amount per unit time, TH , θ TH . Based on this determination result, the display control unit 303 determines whether to change the display state of the display unit 206. The threshold ranges α, β of the reading posture and the threshold ψ of the change amount of the posture TH , θ TH are stored in the ROM 202 or the storage unit 204 as preset information 330 in advance. 【0067】 That is, whether it is the reading posture or not is determined by whether a predetermined condition is satisfied. The condition is that the posture of the user terminal 2 is included within the predetermined threshold ranges α, β. Alternatively, the condition may be that the change amount of the posture of the user terminal 2 per unit time is equal to or greater than the predetermined threshold ψ TH , θ TH . 【0068】 Returning to the explanation of Figure 3, the display control unit 303 displays various screens corresponding to the various functions of the payment application 300 on the display unit 206 of the user terminal 2. The display control unit 303 acquires screen data 310 for the various screens from the storage unit 204 in response to user operations and displays it on the display unit 206. At that time, identification information 320 and balance information of the electronic account acquired from the electronic payment server 5 may also be reflected on the screen. For example, when the user double-tap the startup icon for the payment application 300 displayed on the home screen of the user terminal 2, the payment application 300 starts. When the payment application 300 starts, the display control unit 303 displays the top screen of the payment application 300. The contents of the top screen will be described later. 【0069】 In the first embodiment, the display control unit 303 changes the display state of the display unit 206 of the user terminal 2 based on the posture information input from the posture detection unit 302. If the posture information input from the posture detection unit 302 satisfies the reading posture conditions, the display control unit 303 transitions the top screen displayed on the display unit 206 of the user terminal 2 to the code enlargement screen. If the posture information input from the posture detection unit 302 is not included in the threshold ranges α and β set as reading postures, the display control unit 303 maintains the normal top screen display state. The code enlargement screen will be described later. 【0070】 Whether the display control unit 303 changes the display state according to the orientation of the user terminal 2, that is, whether to enable the turnover mode, is predetermined and stored in the storage unit 204 as setting information 330 for the payment application 300. Alternatively, the user may set this in the setting unit 304, and this setting information 330 may be stored in the storage unit 204. 【0071】 The setting unit 304 accepts the setting of the operating mode. The operating mode that changes the display state of the display unit 206 according to the orientation of the user terminal 2 is referred to as the turnover mode in the following description. The setting unit 304 accepts the setting to enable or disable the turnover mode and stores the setting information 330 in the storage unit 204. The operation of the setting unit 304 will be described in the fourth embodiment described later. 【0072】 (Display control processing) The flow of the display control process in the first embodiment will be explained with reference to Figure 8. Figure 8 is a flowchart of the display control process in the first embodiment. The process shown in the flowchart of Figure 8 is written in the program of the payment application 300 installed on the user terminal 2. The program is stored in the storage unit 204, called by the CPU 201, loaded into RAM 203, and executed. When the user operates the startup icon of the payment application 300 and the payment application 300 is started, the CPU 201 starts this process. In the following explanation, the symbol "S" represents a step. 【0073】 In S801, the CPU 201 first obtains screen data for the top screen 900 of the payment application 300 from the storage unit 204 and displays it on the display unit 206 as shown in Figure 9. 【0074】 Figure 9 shows an example of the top screen 900 in its normal state. The top screen 900 includes a code area 910, a menu area 920, a function selection area 930, a balance display area 940, a fixed display area 950, etc. Inside the code area 910, the first identification code 911 and the second identification code 912 are displayed as user codes that encode the user's identification information. In addition, payment method 913 and electronic account balance information may be displayed inside the code area 910. In the area to the right of the code area 910, a credit payment button, which is operated when transitioning to the credit payment screen, may be displayed. The fixed display area 950 displays a payment button 951. The payment button 951 is a button that is operated when transitioning to the payment screen where the first identification code 911 and the second identification code 912 are displayed in an enlarged view. 【0075】 In S802, the CPU201 detects the orientation of the user terminal 2 at predetermined time intervals. If the predetermined time interval has elapsed (S802; YES), proceed to S803. Otherwise (S802; NO), wait for the time interval to elapse. The time interval is arbitrary, but for example, the orientation is detected at a period of about 10 to 50 Hz. 【0076】 In S803, the CPU 201 reads the detected values ​​from the accelerometer 212 and the gyroscope 213, respectively. 【0077】 In S804, the CPU201 determines the orientation of the user terminal 2 based on the detected values ​​read in S803. As described above, the orientation is the orientation of the user terminal 2 relative to a reference orientation, or the amount of change in orientation per unit time, and is determined for at least the pitch and yaw directions. 【0078】 In S805, the CPU 201 determines whether the orientation of the user terminal 2 has changed to a reading orientation. The reading orientation, as described above, is determined by determining whether the rotation angle in the yaw direction is within threshold range α and the rotation angle in the pitch direction is within threshold range β, relative to the reference orientation. The threshold range α is in the range of θ1 or more and less than θ2 (θ1 ≤ α < θ2). The threshold range β is in the range of ψ1 or more and less than ψ2 (ψ1 ≤ β < ψ2). These threshold ranges α and β are predetermined and stored as described above. The threshold ranges α and β are threshold ranges suitable for reading the identification code by the mounted code reader 31. Furthermore, it is preferable that the threshold ranges α and β are determined based on the inclination angle of the reading surface 40 of the mounted code reader 31. In addition, the threshold ranges α and β are determined to include an appropriate margin based on the operability of the user terminal 2, the positional relationship between the mounted code reader 31 and the user, the range of motion of the wrist, etc. 【0079】 Alternatively, in S805, the CPU201 determines that the amount of change in attitude per unit time is the threshold θ TH ψ TH Determine whether the value is greater than or equal to the specified value. 【0080】 If user terminal 2 is in the reading position (S805; YES), proceed to S806. If user terminal 2 is not in the reading position (S805; NO), proceed to S807. 【0081】 In S806, the CPU 201 transitions the display on the display unit 206 from the top screen 900 to the code enlargement screen 1000. The code enlargement screen 1000 will be described later. After transitioning to the code enlargement screen 1000, the system returns to S802 and repeats steps S802 to S807. 【0082】 In other words, if the user terminal 2 changes its posture to one other than the reading posture while the code enlargement screen is displayed on the display screen, the CPU 201 controls the display unit 206 to return from the code enlargement screen to the normal state (normal top screen 900). 【0083】 In S807, CPU201 maintains the display of the top screen 900 in its normal state. That is, it maintains the top screen 900 as shown in Figure 9. Then, it proceeds to S808. 【0084】 In S808, CPU201 determines whether an operation to leave the top screen 900 has occurred. For example, if the payment button is pressed, the scan button is pressed, an operation to call up a mini-app is performed, or an operation to close the top screen 900 is performed, CPU201 determines that an operation to leave the top screen 900 has occurred and terminates this flowchart. If no operation to leave the top screen 900 is performed, the process returns to S802 and repeats the process from S802 to S808. 【0085】 Furthermore, if the user terminal 2's orientation changes to an angle other than the reading orientation while the code enlargement screen is displayed, the display control unit 303 may perform control to maintain the display of the code enlargement screen. In that case, in the flowchart of Figure 8, after transitioning to the code enlargement screen at S806, the process proceeds to S808. 【0086】 Figure 10 shows an example of the code enlargement screen 1000. The code enlargement screen 1000 of the first embodiment is a screen that is accessed when the user terminal 2 changes its orientation to a reading orientation while the top screen 900 is displayed. The code enlargement screen in Figure 10 is displayed in portrait mode. Portrait mode means that the vertical direction of the screen coincides with the longitudinal axis of the user terminal 2 (the Y-axis in Figure 4). The code enlargement screen 1000 displays the code area 1010, mode display 1020, message area 1050, etc. When transitioning to the code enlargement screen 1000, the menu area 920, function selection area 930, balance display area 940, fixed display area 950, etc., which were displayed on the normal top screen 900 are not displayed. Therefore, the display state does not include electronic account balance information, point information, account information, credit information, etc. Therefore, the code enlargement screen 1000 can have a screen layout specialized for code reading in store scanning. 【0087】 The code area 1010 displays the first identification code 1011 and the second identification code 1012. The payment method may also be displayed within the code area 1010. 【0088】 Let's compare the code area 1010 in Figure 9 (the top screen in the normal state) with the code enlargement screen 1000 in Figure 10. Compared to the code area 910 in Figure 9, the code area 1010 in Figure 10 is displayed enlarged. When the code area 1010 is enlarged, the first identification code 1011 and the second identification code 1012 displayed within it are also enlarged. The display control unit 303 controls the enlarged code area 1010 so that its width does not exceed the display range (display size) of the display unit 206. Alternatively, the display control unit 303 controls the size of the enlarged first identification code 1011 and the second identification code 1012 so that they do not exceed the display range of the display unit 206. 【0089】 Mode indicator 1020 displays text or a mark indicating that the current operating mode is turnover mode. 【0090】 The message area 1050 is the area where messages such as message 1051 regarding the turnover mode are displayed. Message 1051 displays an explanation of the turnover mode and information indicating that the mode can be switched, such as "What is turnover mode? When you tilt the terminal, the payment screen will be displayed. This setting can be changed." In the first embodiment, the payment screen mentioned in the message refers to the code enlargement screen 1000 in Figure 10. The message area 1050 also displays a link 1052 to transition to the settings screen for switching modes, and an "×" button 1053 which is used to hide the message area 1050. By displaying the message area 1050, the user can be made aware that the screen switches depending on the tilt of the terminal, without having to perform complicated operations such as viewing a help menu, and can be informed that the user can change this behavior in the settings. If the link 1052 to the settings screen in the message area 1050 is touched, the user proceeds to the mode setting screen described later. If the "×" button 1053 is touched, the message area 1050 is closed. 【0091】 Note that the message area 1050 does not necessarily have to be displayed on the code enlargement screen 1000. Also, the display control unit 303 may control the display so that the message area 1050 is not displayed after it has been displayed multiple times. By controlling it in this way, a simpler screen layout can be realized once the user has become accustomed to the screen switching depending on the angle (orientation) of the user terminal 2. 【0092】 While the code enlargement screen 1000 is displayed, the CPU 201 executes the processing on the code enlargement screen 1000. If an identification code is read on the code enlargement screen 1000, the payment process is executed. If the link 1052 to the settings screen in the message area 1050 is touched, the user proceeds to the mode setting screen. 【0093】 As described above, the payment application 300 of the first embodiment tracks the orientation information of the user terminal 2, and when the orientation of the user terminal 2 changes to a predetermined reading orientation, it can transition from the top screen 900 to the code enlargement screen 1000. Therefore, when performing a store scan using the mounted code reader 31 installed in the store, the user can display the code enlargement screen, which is the payment screen, simply by holding the display screen over the reading surface 40 of the mounted code reader 31. Thus, it is possible to transition to the payment screen with only one hand, improving usability. Furthermore, on the screen after the transition, the size of the identification code is enlarged to make it easier for the mounted code reader 31 to read, enabling smooth payment processing. In addition, a threshold based on the tilt angle of the reading surface 40 of the mounted code reader 31 and a threshold margin (threshold range) are set as conditions for determining the reading orientation, improving usability in store scans using the mounted code reader 31. Furthermore, the code enlargement screen, which is accessed when the user terminal 2 changes to a predetermined reading position, has a simpler screen layout compared to the top screen, specifically designed for payment processing. Since it does not contain information such as electronic account balance information, point information, account information, and credit card information, it prevents snooping on the displayed information and misuse of the information, improving security during store scanning. This allows users to use the payment app 300 with peace of mind. 【0094】 <Example 1> In the first embodiment, the screen to which the user transitions when the reading orientation changes is a vertically displayed code enlargement screen 1000 as shown in Figure 10, but the destination screen is not limited to this example. 【0095】 Figure 11 shows an example of a code enlargement screen according to Modification 1 of the First Embodiment. Hereinafter, the code enlargement screen shown in Figure 11 will be referred to as the 2D code enlargement screen 1100. The 2D code enlargement screen 1100 is another example of a screen that is transitioned to when the orientation of the user terminal 2 changes to a reading orientation. The 2D code enlargement screen 1100 is displayed in a vertical display state. The 2D code enlargement screen 1100 in Figure 11 displays the code area 1110, mode display 1020, message area 1050, etc. When transitioning to the 2D code enlargement screen 1100, the menu area 920, function selection area 930, balance display area 940, fixed display area 950, etc. that were displayed on the top screen 900 are not displayed. Therefore, similar to the First Embodiment, a screen layout specialized for code reading in store scanning can be used. 【0096】 Within the code area 1110, the first identification code 1111 and the second identification code 1112 are displayed as user codes that encode the user's identification information. The payment method may also be displayed within the code area 1110. In Figure 11, the second identification code 1112 is displayed in a further enlarged view compared to the code enlargement screen 1000 in Figure 10. The mode display 1020 and the message area 1050 are the same as in the first embodiment, so their description is omitted. 【0097】 As explained above, by changing the screen that transitions when the user terminal 2 changes from a reading position to the 2D code enlargement screen 1100 shown in Modification 1, it is particularly suitable for a mounted code reader 31, which has a wider reading surface 40 compared to a handheld code reader, and enables smooth and accurate reading of 2D codes. 【0098】 <Modification 2> Figure 12 shows an example of a code enlargement screen according to a modification 2 of the first embodiment. Hereinafter, the screen shown in Figure 12 will be referred to as the horizontal code screen 1200. The horizontal code screen 1200 is another example of a screen that transitions to when the orientation of the user terminal 2 changes to a reading orientation. The horizontal code screen 1200 is displayed in a horizontal display state. Horizontal display is a display state in which the vertical direction of the screen is perpendicular to the longitudinal axis of the user terminal 2 (the Y axis in Figure 4). In the horizontal code screen 1200, the code area 1210 is enlarged to nearly the size of the longitudinal direction of the display range, and the menu area 920, function selection area 930, balance display area 940, fixed display area 950, etc. that were displayed on the top screen 900 are not displayed. Therefore, similar to the first embodiment, a screen layout specialized for code reading in store scanning can be used. 【0099】 Within the code area 1210, the first identification code 1211 and the second identification code 1212 are displayed as user codes that encode the user's identification information. The payment method may also be displayed within the code area 1210. 【0100】 Since the horizontal code screen 1200 in Figure 12 is displayed horizontally, the longitudinal direction of the first identification code 1211 can be displayed so that it matches the longitudinal direction of the display range of the user terminal 2. Therefore, the first identification code 1211 can be further enlarged compared to the code enlargement screen 1000 in Figure 10. Similarly, the second identification code 1212 can also be displayed enlarged compared to the code enlargement screen 1000 in Figure 10. 【0101】 In the horizontal code screen 1200, the mode display and message area are not shown in the example in Figure 12, but they may be displayed in a position that does not overlap with the first identification code 1211 and the second identification code 1212. 【0102】 As explained above, by making the screen that transitions when the user terminal 2 changes its orientation to a reading orientation the horizontal code screen 1200 shown in Modified Example 2, the one-dimensional code can be displayed larger compared to the vertically displayed code enlargement screen 1000 shown in the first embodiment. In particular, the one-dimensional code can be read smoothly and accurately by the mounted code reader 31, which has a wider reading surface 40 compared to a handheld code reader. 【0103】 <Variation 3> Figure 13 shows an example of a code enlargement screen according to modification 3 of the first embodiment. The screen shown in Figure 13 is another example of a screen that transitions to when the user terminal 2 changes its orientation to a reading orientation. The screen shown in Figure 13 is the same screen as the payment screen 1300 for store scanning that transitions to when the payment button 951 displayed on the top screen 900 is operated. In other words, the existing payment screen 1300 can be used in turnover mode as well, without having to prepare a new code enlargement screen for turnover mode as shown in Figures 10 to 12. 【0104】 The payment screen 1300 is a vertically oriented screen and includes a code area 1310, a barcode payment button 1301, and a scan payment button 1302. The menu area 920, function selection area 930, balance display area 940, fixed display area 950, etc., which were displayed on the top screen 900, are not displayed. 【0105】 The barcode payment button 1301 is a button that is operated to transition to a screen containing a barcode, which is the first identification code 1311. The screen to which the user transitions when the barcode payment button 1301 is operated may be, for example, the code enlargement screen shown in Figures 10 to 12, or the barcode payment button 1301 may be disabled since the payment screen 1300 is already displayed. The scan payment button 1302 is a button that is operated to transition to the scan screen. The scan screen is a screen for the user terminal 2 to read (take a picture of) a store code image 32, such as a QR code, displayed in the store during a user scan. 【0106】 Within the code area 1310, the first identification code 1311 and the second identification code 1312 are displayed as user codes that encode the user's identification information. The code area 1310, the first identification code 1311, and the second identification code 1312 are displayed enlarged compared to the code area 910, the first identification code 911, and the second identification code 912 displayed on the top screen 900. The enlarged code area 1310 is controlled by the display control unit 303 so that its width does not exceed the display range (display size) of the display unit 206. Alternatively, the enlarged first identification code 1311 and the second identification code 1312 are controlled by the display control unit 303 so that they do not exceed the display range of the display unit 206. 【0107】 Furthermore, the code area 1310 displays the balance area 1313, the points area 1314, etc. The balance area 1313 displays the balance value of the electronic account. When the display toggle button 1315 is touched, the display / hide of the balance value can be toggled. When the arrow 1316 is touched, the user transitions to other screens related to the balance, such as the payment method settings screen or the charge screen. The points area 1314 displays the number of points and a slide button 1317 for switching whether or not to use points for payment. 【0108】 In the payment screen 1300 shown in Figure 13, the menu area 920, function selection area 930, balance display area 940, fixed display area 950, etc., are not displayed, and the code area 1310 is displayed larger than on the top screen. Therefore, a screen layout specifically for store scanning can be created. 【0109】 Furthermore, the screen that transitions when the user terminal 2 changes its orientation to a reading orientation may be the code enlargement screen shown in Figure 14. Figure 14 shows a code enlargement screen with a message area 1050 superimposed on the payment screen 1300 of Figure 13. Hereinafter, the code enlargement screen of Figure 14 will be referred to as the payment screen with message 1400. In the payment screen with message 1400 shown in Figure 14, the message area 1050 is superimposed on the barcode payment button 1301 and the scan payment button 1302 of the payment screen 1300 of Figure 13. To hide the message area 1050, the user can touch the "×" button 1053. Also, as mentioned above, the message area 1050 may be controlled to not be displayed after being displayed multiple times. 【0110】 After transitioning to the payment screens 1300 and 1400 shown in Figures 13 and 14, if the user terminal 2 changes its posture to one other than the reading posture, it is preferable to maintain the payment screens 1300 and 1400. This is because it is assumed that the user will assume a posture other than the reading posture in order to operate the payment screens 1300 and 1400. 【0111】 As explained above, according to Modification 3, the existing payment screen 1300 for store scanning can be used as a screen to transition to in the reading position without having to prepare a new code enlargement screen for turnover mode. For the user, payment processing can be done using the familiar payment screen 1300. In addition, by operating the balance area 1313 and point area 1314 displayed on the payment screen 1300, operations such as charging the balance and using points can also be performed, thus enhancing the functionality when the user terminal 2 is in a different position. 【0112】 Although the first embodiment and its modifications have been described above, this disclosure is not limited to these examples. When the user changes to a reading position, the brightness of the code area may be increased, making the code area brighter than other areas. This improves the accuracy of the code reader in reading the identification code. In addition, the user terminal 2 may be configured to vibrate when the display state of the screen is switched due to a change in the reading position. The user can then be notified that the display state of the screen has switched by the vibration. 【0113】 <Second Embodiment> Next, a second embodiment of the present disclosure will be described. In the second embodiment, when the orientation of the user terminal 2 changes to a reading orientation, the code area of ​​the top screen is enlarged, and the top screen is further displayed in a concealed state. Note that the configuration of the payment application 300, the user terminal 2, the store terminal 3, and the electronic payment server 5 in the second embodiment are the same as in the first embodiment, so redundant explanations will be omitted, and the same parts will be denoted by the same reference numerals. 【0114】 Figure 15 illustrates an example of the top screen 1500 displayed in a code-enlarged / concealed state. In the second embodiment, when the user terminal 2 changes its orientation to a reading orientation while the normal top screen 900 (Figure 9) is displayed, the display control unit 303 changes the normal top screen 900 displayed on the display unit 206 to a code-enlarged / concealed state as shown in Figure 15. The concealed state hides or masks some of the information that was displayed on the display unit 206 in the normal display state. Specifically, the information to be hidden includes at least one of the following: balance information, point information, account information, and credit information. Hiding means not displaying, while masking means a display state in which a mask is superimposed on the displayed information or replaced with information to hide it. As a result, in store scans that are likely to be seen by many people, information such as balance information, point information, account information, and credit information displayed on the screen is hidden, allowing users to proceed with payment with peace of mind. 【0115】 As shown in Figure 15, in the top screen 1500 with the code enlarged / concealed state, the code area 1510 is enlarged compared to the top screen 900 in the normal state shown in Figure 9. As a result, the first identification code 1511 and the second identification code 1512 within the code area 1510 are also displayed enlarged. The display control unit 303 controls the enlarged code area 1510 so that its width does not exceed the display range (display size) of the display unit 206. Alternatively, the display control unit 303 controls the size of the enlarged first identification code 1511 and the second identification code 1512 so that they do not exceed the display range of the display unit 206. 【0116】 Additionally, in the top screen 1500 with the code enlarged / concealed, the balance display area 1540 is displayed in a concealed state. The code area 910, menu area 920, function selection area 930, and fixed display area 950 are the same as the top screen 900 in the normal state. 【0117】 Figure 9 (normal state) and Figure 15 (hidden state) compare the balance display area 1540. In the balance display area 940 of Figure 9, the numerical values ​​of points in use, the amount available on the card, and the electronic account balance are displayed in the respective display fields. In the balance display area 1540 of Figure 15, the numerical values ​​of points in use, the amount available on the card, and the electronic account balance are replaced with "***". In other words, the electronic account balance information, point information, account information, and credit information are masked. The masked display is not limited to "***" and other display formats that hide values ​​are also acceptable. Alternatively, instead of masking, the numerical values ​​of points and amounts may be hidden. 【0118】 Alternatively, the message area 1050 may be superimposed on the top screen 1500 in the code enlargement / confidentiality state. 【0119】 Figure 16 shows the top screen 1600 with a message area 1050 superimposed on the top screen 1500 in the code enlargement / concealment state shown in Figure 15. In Figure 16, the message area 1050 is superimposed on the balance display area 1540. To hide the message area 1050, the user can touch the "×" button 1053. As mentioned above, the message area 1050 may be controlled to not be displayed after being displayed multiple times. In this way, when the message area 1050 is superimposed on the balance display area 1540, the electronic account balance information, point information, account information, and credit information are masked. The display position of the message area 1050 can be any position as long as it does not overlap with the code area 1510. 【0120】 Figure 17 is a flowchart showing the flow of the display control process in the second embodiment. The process shown in the flowchart of Figure 17 is written in the program of the payment application 300 installed on the user terminal 2. The program is stored in the memory unit 204, called by the CPU 201, loaded into RAM 203, and executed. This flowchart starts when the user operates the startup icon of the payment application 300 and the payment application 300 is launched. 【0121】 The processes shown in S1701 to S1705 of this flowchart are the same as those in S801 to S805 of the flowchart for the display control process of the first embodiment (Figure 8). The conditions for determining the reading posture are also the same as in the first embodiment. If the posture of the user terminal 2 changes to the reading posture while the top screen is displayed (S1705; YES), proceed to S1706 and switch the display of the top screen to code enlargement / concealment display. Otherwise (S1705; NO), proceed to S1707 and maintain the normal display state (top screen 900 in Figure 9). 【0122】 In S1706, the CPU 201 switches the screen displayed on the display unit 206 from the normal top screen 900 to the top screen 1500 in the code-enlarged / concealed state shown in Figure 15. Alternatively, it switches to the top screen 1600 in the code-enlarged / concealed state shown in Figure 16. 【0123】 Figure 18 is a flowchart showing the flow of the code enlargement and concealment display process in S1706 of Figure 17. The process shown in the flowchart of Figure 18 is written in the program of the payment application 300 installed on the user terminal 2. The program is stored in the memory unit 204, called by the CPU 201, loaded into RAM 203, and executed. This flowchart is started when the orientation of the user terminal 2 is determined to be in a reading orientation during the display control process shown in Figure 17. 【0124】 In S1801, the CPU 201 hides and displays the electronic account balance information, point information, account information, and credit information included in the normal state top screen 900 displayed on the display unit 206. In the examples of Figures 15 and 16, the numerical values ​​of points in use, available card amount, and electronic account balance in the balance display area 1540 are changed to "***" and displayed. If the account number of the electronic account or the card number of the credit card is displayed along with the balance information, this information may also be hidden. Not limited to the balance display area 1540, if, for example, the code area displays the electronic account balance information or account information (amount, account number, etc.), the CPU 201 in S1801 may hide or mask the balance information etc. in the code area 1510. Alternatively, the balance display area 1540 may be masked by superimposing the message area 1050 onto the balance display area 1540. 【0125】 In S1802, the CPU 201 enlarges the display of the identification code included in the top screen shown on the display unit 206. In the examples of Figures 15 and 16, the code area 1510 is enlarged in the width direction of the display screen, and as a result, the first identification code 1511 and the second identification code 1512 are also enlarged and displayed. After that, the flowchart in Figure 18 is terminated, and the process proceeds to S1708 in Figure 17. 【0126】 On the top screen, the code reader 31 accepts the reading of the identification code regardless of whether the screen is in the normal state or in the code enlarged / concealed state. If the identification code is read, the CPU 201 works in conjunction with the store terminal 3 to execute the payment process. 【0127】 After processing S1706 or S1707, CPU201 proceeds to processing S1707. In S1708, CPU201 determines whether an operation to leave the top screen has been performed. If no operation to leave the top screen has been performed (S1708; NO), the process returns to S1702 and repeats the processes from S1702 to S1707. If an operation to leave the top screen has been performed, such as pressing the payment button, the scan button, calling up a mini-app, or closing the top screen (S1708; YES), the flowchart shown in Figure 17 terminates. 【0128】 As described above, according to the payment application 300 of the second embodiment, when the user terminal 2 changes its orientation to a predetermined reading orientation, the display of the top screen 900 in its normal state is switched to a code enlargement / concealment state. This enlarges the identification code and allows the user to transition to a screen where the electronic account balance information, point information, account information, and credit information are not displayed. Therefore, operability in store scanning is improved, and the accuracy of code reading is improved. In addition, since certain information is displayed concealed, security in store scanning is improved. Furthermore, because the display state of a part of the same top screen is changed before and after the change in orientation to reading, the functions of this disclosure can be used even in environments where it is difficult to update screen data, such as when the communication environment is poor. 【0129】 <Third Embodiment> Next, a third embodiment of the present disclosure will be described. In the third embodiment, when the orientation of the user terminal 2 changes to a reading orientation, the code area of ​​the top screen is enlarged, and the area excluding the code area (first area) (second area) is displayed in a darkened state. Note that the configuration of the payment application 300, the user terminal 2, the store terminal 3, and the electronic payment server 5 in the third embodiment are the same as in the first embodiment, so redundant explanations will be omitted, and the same parts will be denoted by the same reference numerals. 【0130】 Figure 19 is a diagram illustrating an example of a display screen in the third embodiment. In the third embodiment, when the user terminal 2 changes its posture to a reading posture while the top screen is displayed, the display control unit 303 changes the top screen to a darkened state as shown in Figure 19. 【0131】 In the blacked-out top screen 1900, compared to the normal top screen 900 shown in Figure 9, the second area 1920, which is the area within the display screen excluding the code area 1910 and the message area 1050, is displayed in black. That is, the second area 1920 is displayed darker than the code area 1910 and the message area 1050. In other words, the code area 1910 and the message area 1050 are displayed brighter than the second area 1920. Also, the code area 1910 is enlarged. As a result, the first identification code 1911 and the second identification code 1912 within the code area 1910 are also displayed enlarged. In addition, the message area 1050, which contains messages related to the turnover mode, is displayed. 【0132】 The message area 1050 does not necessarily have to be displayed on the blacked-out top screen 1900. For example, after displaying the message area 1050 multiple times, it may be controlled so that it is not displayed again. In that case, the area within the display screen excluding the code area 1910 becomes the second area 1920, and in the blacked-out top screen 1900, this second area 1920 is displayed in a blacked-out state. 【0133】 The second area 1920, which is displayed in a darkened state, includes a menu area 920, a function selection area 930, a balance display area 1540, and a fixed display area 950. The balance information, point information, account information, and credit information within the balance display area 1540 are preferably hidden or masked, similar to the second embodiment. 【0134】 Figure 20 is a flowchart showing the code enlargement and concealment display process in the third embodiment. The process shown in the flowchart of Figure 20 is written in the program of the payment application 300 installed on the user terminal 2. The program is stored in the memory unit 204, called by the CPU 201, loaded into RAM 203, and executed. This flowchart is executed at S1706 in Figure 17. That is, the process in Figure 20 is started when it is determined that the user terminal 2 is in a reading position. 【0135】 In S2001, the CPU 201 enlarges the code area 1910 included in the top screen displayed on the display unit 206. In the example in Figure 19, the code area 1910 is enlarged and displayed within a range that does not exceed the width of the display screen. As a result, the first identification code 1911 and the second identification code 1912 are also enlarged and displayed. 【0136】 In S2002, CPU201 dims the area of ​​the display screen excluding code area 1910 (second area 1920). That is, CPU201 lowers the brightness value of second area 1920 from the normal state. This ensures that information other than the identification code required for payment is displayed in a confidential state on the top screen. When dimming, CPU201 may also display message area 1050. If message area 1050 is displayed, the area excluding code area 1910 and message area 1050 is treated as second area 1920 and dimmed. 【0137】 In the S2002 process, it is sufficient that the second area 1920 is displayed darker than the code area 1910 and the message area 1050. That is, the display control unit 303 lowers the brightness value of the second area 1920 to the same or lower brightness value as the normal state. Furthermore, the display control unit 303 may increase the brightness values ​​of the code area 1910 and the message area 1050 above the normal state. This makes it possible to display the code area 1910 and the message area 1050 brightly even when the top screen 900 is displayed darkly in the normal state according to the user settings. Information other than the identification code necessary for payment is displayed in a confidential state on the top screen, and the visibility of the code area 1910 and the message area 1050 is improved. 【0138】 As shown in Figure 19, when the top screen is dimmed and an identification code is read, the CPU 201 works with the store terminal 3 to execute the payment process. If the link 1052 to the settings screen in the message area 1050 is touched, the user proceeds to the mode setting screen described later. If the "×" button 1053 is touched, the message area 1050 is closed. 【0139】 In S2003, CPU201 determines whether the second area 1920, which is currently darkened, has been tapped. If the second area has been tapped (S2003; YES), the process proceeds to S2004. 【0140】 In S2004, CPU201 returns the display state of the top screen to the normal display state. The normal display state is the display state of the top screen before changing to the code enlargement / concealment state. After that, the flowchart in Figure 20 is terminated and the process proceeds to S1708 in Figure 17. 【0141】 If no tap operation is performed in the darkened area during S2003 (S2003; NO), the flowchart in Figure 20 is terminated. After terminating the flowchart in Figure 20, the process proceeds to S1708 in Figure 17. 【0142】 As explained above, according to the payment application 300 of the third embodiment, when the user terminal 2 changes its orientation to a reading orientation, the display state of the normal top screen 900 can be transitioned to a top screen 1900 in a darkened state in which the area excluding the code area 1910 (second area 1920) is darkened. Therefore, during store scanning, information such as electronic account balance information, point information, account information, and credit information can be displayed in a darkened state, making it difficult for people around the user to see. This improves the security of store scanning. In addition, since the code area 1910 is enlarged and displayed brighter than the darkened area, the reading accuracy of the code reader 31 is improved. As a result, the user can use the payment application 300 with peace of mind and code reading can be performed smoothly. 【0143】 <Fourth Embodiment> Next, a fourth embodiment of this disclosure will be described. It is preferable that the user can switch between enabling and disabling the switching operation to the display state according to the orientation of the user terminal 2, as shown in the first to third embodiments, through a setting operation. The operation of switching the display state of the screen when the orientation of the user terminal 2 changes to the reading orientation, which is the orientation for reading by the mounted code reader 31, is called the turnover mode. As the fourth embodiment, the setting function for the turnover mode will be described. Note that the configuration of the payment application 300, the user terminal 2, the store terminal 3, and the electronic payment server 5 in the fourth embodiment are the same as in the first embodiment, so redundant explanations will be omitted and the same parts will be denoted by the same reference numerals. 【0144】 The turnover mode setting function is one of the program modules of the payment application 300 and corresponds to the setting unit 304 shown in Figure 3(b). In other words, the CPU 201 functions as the setting unit 304 by executing the program module. 【0145】 The setting unit 304 receives a setting from the user to enable or disable the turnover mode and stores it in the storage unit 204 as setting information 330 for the payment application 300. If the turnover mode is enabled by the setting unit 304, the posture detection unit 302 and the display control unit 303 change the state of the screen displayed on the display unit 206 based on the posture of the user terminal 2, as shown in the first to third embodiments. If the turnover mode is disabled by the setting unit 304, the posture detection unit 302 does not perform posture detection of the user terminal 2. Therefore, the display state is not changed according to the posture of the user terminal 2. 【0146】 (Setup process) Referring to Figure 21, the flow of the setting process executed by the payment application 300 of the fourth embodiment will be explained. The process shown in the flowchart of Figure 21 is written in the program of the payment application 300 installed on the user terminal 2. The program is stored in the storage unit 204, called by the CPU 201, loaded into RAM 203, and executed. When the payment application 300 is started and the turnover mode setting is called on the top screen, the CPU 201 starts this process. The turnover mode setting is called when "Turnover Mode Setting" is selected from the setting menu on the account management screen, which is accessed from the account button displayed on the top screen (the button in the lower right of the top screen 900 in Figure 9). Alternatively, it is called when the user touches the link 1052 to the mode setting screen in the message area 1050. 【0147】 In S2101, the CPU 201 displays the turnover mode setting screen 2200 on the display unit 206. 【0148】 In S2102, the CPU 201 retrieves setting information regarding the currently set turnover mode from the setting information 330 stored in the memory unit 204. The setting information regarding the turnover mode indicates either enable or disable. In S2102, the CPU 201 reflects the retrieved setting information regarding the current turnover mode on the setting screen 2200. 【0149】 Figure 22 shows an example of the turnover mode setting screen 2200. As shown in Figure 22, the setting screen 2200 displays buttons to select either Enable 2201 or Disable 2202, and a check mark 2203 indicating the current setting information. In the example in Figure 22, the check mark 2203 is displayed for Enable 2201. 【0150】 In S2103, if the user performs an operation to switch the settings related to the turnover mode (S2103; YES), the process proceeds to S2104. The switching operation is performed by the user selecting either the enable button 2201 or the disable button 2202 displayed on the settings screen 2200. The selection operation may be performed by tapping, for example. If the user operates a button different from the current setting, the CPU 201 determines that the turnover mode has been switched and proceeds to S2104. 【0151】 In S2104, CPU201 switches the turnover mode setting to the selected setting. For example, if the turnover mode setting information obtained in S2102 is "enabled" and the user selects "disabled" 2202 on setting screen 2200, CPU201 switches the turnover mode setting to disabled. Also, for example, if the turnover mode setting information obtained in S2102 is "disabled" and the user selects "enabled" 2201 on setting screen 2200, CPU201 switches the turnover mode setting to enabled. 【0152】 In S2105, the CPU 201 saves the settings information that was switched in S2104 to the storage unit 204, and this flowchart ends. 【0153】 Furthermore, if the same button as the current setting is selected in S2103, or if the button to return to the previous screen is operated, the CPU 201 determines that the turnover mode will not be switched on or off (S2103; NO). In that case, S2104 to S2105 are skipped, and the processing of the flowchart in Figure 21 is terminated. Furthermore, if the operation to return to the previous screen is performed on the settings screen 2200, the CPU 201 displays the screen that was displayed before the settings screen 2200 was displayed (account management screen, or top screen, code enlargement screen, etc.) on the display unit 206, and then terminates the processing of the flowchart in Figure 21. 【0154】 As explained above, the payment application 300 of the fourth embodiment allows the user to enable or disable the turnover mode through a setting operation. The turnover mode setting information 330 is acquired by the CPU 201 when the payment application 300 is launched and reflected in subsequent operations. That is, if the turnover mode setting information 330 is set to "enabled", the CPU 201 performs a display switching operation based on the orientation of the user terminal 2, as shown in the first to third embodiments. If the turnover mode setting information is set to "disabled", the CPU 201 does not perform a display switching operation based on the orientation of the user terminal 2. When the turnover mode is set to "disabled", the screen display does not change even if the orientation of the user terminal 2 changes, and screen transitions are performed based on button operations, similar to the conventional payment application 300. 【0155】 Preferred embodiments of this disclosure have been described above with reference to the attached drawings, but this disclosure is not limited to such examples. For example, the content of buttons and information displayed on the screen, the screen layout, and the processing procedures shown in the flowchart are examples and can be modified as appropriate without departing from the technical idea of ​​this disclosure. Furthermore, it is clear that those skilled in the art can conceive of various modifications or alterations within the scope of the disclosed technical idea, and these will naturally also fall within the technical scope of this disclosure. [Explanation of Symbols] 【0156】 1. Electronic payment system 2. User terminals 900 Top screen 1000 Code Enlarged Screen 1100 2D code enlarged screen 1200 Horizontal Code Screen 1300 Payment screen 1400 Payment screen with message 1500 Top screen in enlarged / hidden state 1900 Top screen in blacked-out state 301 Payment Processing Unit 302 Posture detection unit 303 Display Control Unit 304 Settings Section

Claims

[Claim 1] A payment application program installed on a terminal device used by a user of electronic payment in order to use electronic payment using an identification code, wherein the terminal device A detection unit for detecting the orientation of the terminal device, The display control unit controls the display in the display section of the terminal device, The display control unit, A payment application program characterized in that when the orientation of the terminal device detected by the detection unit changes to a first orientation suitable for reading the identification code by a mounted code reader, the display state of the display unit is switched. [Claim 2] The payment application program according to claim 1, characterized in that the first posture is a posture in which the display unit of the terminal device is positioned facing the reading surface of the above-described stationary code reader. [Claim 3] The payment application program according to claim 1, characterized in that the display control unit determines whether or not the terminal device has changed to the first posture based on the amount of rotation of the terminal device about the longitudinal axis of the terminal device. [Claim 4] The payment application program according to claim 3, further characterized in that the display control unit determines whether or not the terminal device has changed to the first posture based on the inclination of the longitudinal axis of the terminal device from the direction of gravity. [Claim 5] The payment application program according to claim 1, characterized in that the threshold for determining whether or not the first posture is in place is determined based on the inclination angle of the reading surface of the stationary code reader described above. [Claim 6] The payment application program according to claim 5, characterized in that the threshold for determining whether or not the first posture is present includes a margin, and the margin is determined based on the range of motion of the person's wrist. [Claim 7] The payment application program according to claim 5, characterized in that the threshold for determining whether or not the first posture is in place includes a margin, and the margin is determined based on the positional relationship between the user and the stationary code reader described above. [Claim 8] The payment application program according to claim 1, characterized in that the detection unit detects the orientation of the terminal device when the top screen, which is displayed after the startup of the payment application program, is shown. [Claim 9] The payment application program according to claim 1, characterized in that the display control unit enlarges and displays the identification code displayed on the display unit when the orientation of the terminal device changes to the first orientation. [Claim 10] The payment application program according to claim 9, characterized in that the display control unit transitions to a code enlargement screen different from the screen displayed before changing to the first posture. [Claim 11] The payment application program according to claim 9, characterized in that the display control unit displays the identification code included in the top screen, which is displayed before changing to the first posture, in an enlarged view within the top screen. [Claim 12] The application program according to claim 9, characterized in that the display control unit displays the identification code enlarged to the maximum size of the horizontal direction of the screen when the vertical direction of the screen coincides with the longitudinal axis of the terminal device. [Claim 13] The application program according to claim 9, characterized in that the display control unit displays the identification code enlarged to the maximum size of the screen in the longitudinal direction when the vertical direction of the screen is perpendicular to the longitudinal axis of the terminal device. [Claim 14] The payment application program according to claim 1, characterized in that when the orientation of the terminal device changes to the first orientation, the display control unit transitions to the payment screen which is set as the destination for transitions made by operating the payment button displayed after the startup of the payment application program. [Claim 15] The payment application program according to claim 1 or 9, characterized in that when the orientation of the terminal device changes to the first orientation, the display control unit hides or masks at least one of the electronic account balance information, point information, account information, and credit information displayed on the display unit. [Claim 16] The payment application program according to claim 1, characterized in that when the orientation of the terminal device changes to the first orientation, the display control unit causes the second region, which is the region excluding the first region, which is the region containing the identification code, to be displayed on the display unit to be darker than the first region. [Claim 17] The payment application program according to claim 1, characterized in that the display control unit returns the display state of the display unit to the state before the change when the orientation of the terminal device changes from the first orientation to an orientation other than the first orientation. [Claim 18] The payment application program according to claim 1, characterized in that the display control unit maintains the display state of the display unit when the orientation of the terminal device changes from the first orientation to an orientation other than the first orientation. [Claim 19] The payment application program according to claim 1, further comprising a setting unit that accepts a setting by the user to enable or disable display control based on the detection of the orientation of the terminal device. [Claim 20] A terminal device used by a user of electronic payment in order to use electronic payment using an identification code, A detection unit for detecting the orientation of the terminal device, The terminal device has a display control unit that controls the display in the display unit, The display control unit, An information processing device characterized in that when the orientation of the terminal device detected by the detection unit changes to a first orientation suitable for reading the identification code by the mounted code reader, the display state of the display unit is switched. [Claim 21] A display control method executed by the computer of a terminal device used by a user of electronic payment in order to use electronic payment using an identification code, A step of detecting the orientation of the terminal device, The steps include controlling the display state of the display unit of the terminal device to switch when the detected orientation of the terminal device changes to a first orientation suitable for reading the identification code by a mounted code reader, A display control method characterized by including the following.

Images