Information processing apparatus and control method

Abstract

The invention relates to an information processing apparatus and a control method, which reduce power consumption without compromising usability. The power supply circuit is supplied with power from a power supply, and the brightness control part controls the brightness of the display and comprises a first reference value under the condition that the power supply type is an external power supply and a second reference value under the condition that the power supply type is a battery and is smaller than the first reference value as a reference value of a brightness setting value which is a brightness setting value. The brightness setting value is set to a user setting value specified by a user according to an operation of the user, and when the power supply type is switched from the external power supply to the battery in a state where the user setting value is larger than a second reference value, brightness reduction processing is executed to reduce the brightness setting value to a value between the user setting value and the second reference value.

Description

Technical Field

[0001] The present application relates to an information processing apparatus and a control method, and more particularly to brightness control of a display. Background Art

[0002] A portable information processing apparatus such as a notebook personal computer (hereinafter sometimes referred to as a "notebook PC") is not always used in an environment where power is supplied from an external power source. Therefore, the information processing apparatus includes a rechargeable battery and consumes the power stored in the battery. The battery life is defined as the period during which the apparatus can continue to operate without receiving power from an external power source, and it is desired to extend the battery life as much as possible.

[0003] For example, Patent Document 1 discloses an information processing apparatus including: an AC adapter that supplies power to a rechargeable battery and a predetermined device; and a switching button for operating modes that switches a priority processing mode in which power is supplied from the AC adapter to various devices and a charging mode in which various devices are shifted to a power saving operation mode and power supply from the AC adapter to the battery is prioritized. The apparatus performs control to switch the priority processing mode and the charging mode by detecting depression of the switching button for operating modes, and to switch the priority processing mode and the charging mode based on the detected remaining capacity of the battery.

[0004] To increase the battery life, it is also considered to use a battery with a larger capacity. However, generally, the larger the capacity of the battery, the larger its size. In response to the portability of the information processing apparatus, it is still important to reduce power consumption. On the other hand, the power consumption of a display in the devices included in the information processing apparatus is sometimes larger than that of other devices. In the above-described information processing apparatus, it is required to reduce the power consumption of the display.

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2010-9538

[0006] Therefore, it is considered to provide a function in the information processing apparatus to determine the brightness of the display according to a power consumption setting and increase it to a desired brightness according to a user operation. With this function, when used in a brighter environment such as outdoors during the day, the display information on the display can be easily seen. However, when returning to a darker environment, it is relatively rare for the user to perform an operation to decrease the brightness that has been temporarily increased. If no operation is performed, the high brightness state is maintained, and thus power may be wasted. Summary of the Invention

[0007] This application is completed to solve the above problems. An information processing apparatus according to one aspect of this application includes: a power supply circuit that supplies power from a power source; and a brightness control unit that controls the brightness of a display. The brightness control unit has a reference value when the power source type is a battery as a reference value of the brightness setting value, that is, the brightness setting value. The brightness setting value is set to a user-specified user setting value according to a user operation. When the user setting value is greater than the reference value when the power source type is a battery, when the power source type is switched from an external power source to a battery, a brightness reduction process of reducing the brightness setting value to a value between the user setting value and the reference value when the power source type is a battery is performed.

[0008] In the above information processing apparatus, it may also be configured that the brightness control unit reduces the brightness setting value from the user setting value by a predetermined change amount in the brightness reduction process.

[0009] In the above information processing apparatus, it may also be configured that the lower the user setting value, the smaller the change amount of the brightness setting value by the brightness control unit in the brightness reduction process.

[0010] In the above information processing apparatus, it may also be configured that in a power control mode with a larger rated power of the main system, the reference value when the power source type is a battery is larger, and the brightness control unit sets the brightness setting value to a reference value corresponding to the combination of the selected power control mode and the power source type.

[0011] In the above information processing apparatus, it may also be configured that the brightness control unit saves the brightness setting value when the main system stops operating, and applies the saved brightness setting value to the display when the main system restarts operating.

[0012] A control method according to a second aspect of this application is a control method of an information processing apparatus. The information processing apparatus includes a power supply circuit that supplies power from a power source and a brightness control unit that controls the brightness of a display. The information processing apparatus has a reference value when the power source type is a battery as a reference value of the brightness setting value, that is, the brightness setting value. The brightness setting value is set to a user-specified user setting value according to a user operation. When the user setting value is greater than the reference value when the power source type is a battery, when the power source type is switched from an external power source to a battery, a brightness reduction process of reducing the brightness setting value to a value between the user setting value and the reference value when the power source type is a battery is performed.

[0013] According to this embodiment, it is possible to reduce power consumption without impairing usability. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is an external view showing an example of the external structure of the information processing apparatus according to the first embodiment.

[0015] Figure 2 It is a schematic block diagram showing an example of the hardware structure of the information processing apparatus according to the first embodiment.

[0016] Figure 3 It is a schematic block diagram showing an example of the functional structure of the information processing apparatus according to the first embodiment.

[0017] Figure 4 It is a diagram showing examples of the setting screen and the guidance screen according to the first embodiment.

[0018] Figure 5 It is a diagram showing an example of the setting of the brightness setting table according to the first embodiment.

[0019] Figure 6 It is a diagram showing a first example of the transition of the brightness setting value based on the change in the usage state.

[0020] Figure 7 It is a flowchart showing an example of the brightness control according to the first embodiment.

[0021] Figure 8 It is a diagram showing a second example of the transition of the brightness setting value based on the change in the usage state.

[0022] Figure 9 It is a flowchart showing an example of the brightness control according to the second embodiment.

[0023] Figure 10 It is an explanatory diagram for explaining a method of setting a reference value of the brightness setting value according to the third embodiment.

[0024] Explanation of Reference Numerals

[0025] 1... Information processing apparatus; 11... Processor; 12... Main memory; 13... Video subsystem; 14... Display; 21... Chipset; 22... BIOS memory; 23... Storage; 24... Audio system; 25... WLAN card; 26... USB connector; 31... EC; 32... Input device; 33... Power supply circuit; 34... Battery; 36... Power button; 32k... Keyboard; 32t... Touchpad; 42... Lid sensor; 44... Acceleration sensor; 48... AC adapter; 48o... Insertion port. Detailed Embodiments

[0026] <First Embodiment>

[0027] Hereinafter, embodiments of the present application will be described with reference to the drawings. First, an overview of the information processing apparatus 1 according to the first embodiment of the present application will be described. In the following description, the case where the information processing apparatus 1 is a notebook PC will be mainly taken as an example. Here, the information processing apparatus 1 is not necessarily limited to a notebook PC, and may also be configured as a tablet terminal device, a smart phone, or the like.

[0028] Figure 1 FIG. 4 is an external view showing an example of the external structure of the information processing apparatus 1 according to the present embodiment.

[0029] The information processing apparatus 1 includes two frames 102 and 104. The frames 102 and 104 each have a horizontally long surface whose width is wider than its height, and have a flat shape whose thickness is thinner than its height. One side surface of each of the frames 102 and 104 faces each other in the width direction and is engaged with each other using hinges 108a and 108b. One of the frames 102 and 104 is rotatably connected to the other around a rotation axis A. That is, by making the angle formed by the surfaces of the frames 102 and 104 (hereinafter, sometimes referred to as "opening angle") variable, the two are opened and closed. An opening angle of 0° or an angle close to 0° (for example, 45° to 60° or less) corresponds to a state where the frames 102 and 104 are closed. An opening angle that is sufficiently large (for example, an angle larger than 45° to 60°) corresponds to a state where the frames 102 and 104 are open. In a state where no external force is applied to the frames 102 and 104, the opening angle is maintained constant.

[0030] The frame 102 is provided with a lid sensor 42 at a position far from the rotation axis A. The lid sensor 42 detects the open / closed state of the frames 102 and 104. In Figure 1 the example, the lid sensor 42 has a magnetic sensor. In the frame 104, a permanent magnet 46 is provided at a position opposite to the lid sensor 42 in a state where the frame 102 is closed. In a state where the frames 102 and 104 are closed, the magnetic sensor approaches the permanent magnet, and thus a relatively strong magnetic field is detected. In a state where the frames 102 and 104 are open, the magnetic sensor is away from the permanent magnet, and thus the detected magnetic field becomes weaker. Therefore, the open / closed state of the frames 102 and 104 is determined based on the intensity of the detected magnetic field. Further, in Figure 1 the example, the frame 102 is further provided with an acceleration sensor 44.

[0031] On the surface of the housing 102, a keyboard 32k, a touchpad 32t, and a power button 36 are arranged. On the side surface in the width direction of the housing 102, an insertion port (socket) 48o is provided. The insertion port 48o has a cavity portion into which the plug of the AC adapter 48 can be inserted. By fitting with the inserted plug, the position of the plug is fixed in a state of contacting the electrodes provided on the inner surface of the cavity portion. DC power is supplied from the AC adapter 48 to the information processing apparatus 1 via the plug inserted into the insertion port 48o.

[0032] In the AC adapter 48, AC power is supplied from a commercial power supply, and the supplied AC power is converted into DC power having a constant voltage (for example, 3V to 12V).

[0033] On the surface of the housing 104, a display 14 is arranged. The display 14 covers most of the surface of the housing 104.

[0034] Figure 2 This is a schematic block diagram showing an example of the hardware configuration of the information processing apparatus 1 according to the present embodiment. The information processing apparatus 1 is configured to include: a processor 11, a main memory 12, a video subsystem 13, a display 14, a chipset 21, a BIOS (Basic Input-Output System) memory 22, a storage 23, an audio system 24, a WLAN (Wireless Local Area Network) card 25, a USB (Universal Serial Bus) connector 26, an EC (Embedded Controller) 31, an input device 32, a power circuit 33, a battery 34, a power button 36, a lid sensor 42, and an acceleration sensor 44.

[0035] The processor 11 executes arithmetic processing in accordance with various commands described in a program, and controls the operation of the entire information processing apparatus 1. As the processor 11, for example, one or more CPUs (Central Processing Unit) can be included.

[0036] The main memory 12 is a writable memory that is used as a read-in area for programs executed by the processor 11 or as a work area for writing processing data of the executed programs. The main memory 12 is configured, for example, to include one or two or more DRAM (Dynamic Random Access Memory) chips. Programs include, for example, an OS (Operating System), a driver for controlling the operation of peripheral devices, various services / utilities (sometimes referred to as "utilities" in this application), application programs (sometimes referred to as "applications" in this application), and the like.

[0037] The processor 11, the main memory 12, and the chipset 21 are the minimum hardware components that make up the main system 110 ( Figure 3 ). In this application, the devices that make up the main system 110 are sometimes collectively referred to as "system devices". System devices are sometimes configured as integrated components (e.g., SoC: System-on-Chip). The main system 110 is the core computer system of the information processing apparatus 1. The processor 11 executes a prescribed program and cooperates with the main memory 12 and other hardware to implement the functions of the main system 110. In this application, "executing a program" or "execution of a program" includes the meaning of performing the processing indicated by the instructions described in the program.

[0038] The video subsystem 13 is a subsystem for implementing functions related to image display. The video subsystem 13 is configured to include a video controller (not shown). The video controller performs the processing indicated by the drawing commands input from the processor 11 and writes the display data obtained through the processing into a video memory (not shown) provided therein. The video controller reads out the display data written from the video memory and outputs the read display data to the display 14.

[0039] The display 14 displays various display screens based on the display data input from the video subsystem 13. The display 14 can be, for example, any type of display such as an LCD (Liquid Crystal Display) or an OLED (Organic Light Emitting Diode) display.

[0040] The display 14 includes a pixel panel and a power supply image circuit (not shown). The surface of the pixel panel forms a two-dimensional plane, and a plurality of pixels are arranged at regular intervals. Each pixel emits light by the power supplied from the drive circuit.

[0041] The power supply image circuit converts the power supplied from the power supply circuit 33 into drive power for emitting light with a brightness corresponding to the signal value of each pixel shown in the display data input from the video subsystem 13. An image is represented by the distribution of the brightness of each pixel. The power supply image circuit multiplies the generated drive power by a gain to adjust the intensity of the drive power. The brightness of the image displayed on the display is adjusted by the adjustment of the intensity. The power supply image circuit outputs the drive power of each pixel with the intensity adjusted to the drive circuit.

[0042] Brightness setting information indicating the correspondence between a set value representing brightness (sometimes referred to as "brightness set value" in this application) and the gain is preset in the power supply image circuit. The power supply image circuit refers to the brightness setting information, determines the gain corresponding to the brightness set value notified from the main system, and adjusts the intensity of the drive power using the determined gain.

[0043] The chipset 21 is connected to one or more peripheral devices and controls the input and output of various data. The chipset 21 has various input / output interfaces and is connected to the corresponding devices. The chipset 21 has controllers corresponding to various input / output methods. For example, the chipset 21 has controllers related to any one or any combination of USB (Universal Serial Bus), Serial ATA (Advanced Technology Attachment), SPI (Serial Peripheral Interface) bus, PCI (Peripheral Component Interconnect) bus, PCI-Express bus, and LPC (Low Pin Connect) bus, etc. In Figure 2 the example, as peripheral devices connected to the chipset 21, the BIOS memory 22, the storage 23, the audio system 24, the WLAN card 25, the USB connector 26, and the EC 31 are exemplified.

[0044] System firmware such as BIOS is pre-stored in the BIOS memory 22. Firmware for controlling the operations of the EC 31 and other devices may also be stored in the BIOS memory 22. The BIOS memory 22 is configured to include a rewritable non-volatile memory (for example, EEPROM (Electrically Erasable Programmable Read Only Memory), flash ROM, etc.).

[0045] The storage 23 has an auxiliary storage device that stores various programs and data executed by the processor 11. The storage 23 is configured to include a rewritable non-volatile memory. The storage 23 can also be any one of an SSD (Solid State Drive) or an HDD (Hard Disk Drive).

[0046] The audio system 24 performs input, output, and recording of sound data. The audio system 24 may also include a speaker. The speaker plays the sound based on the sound data input to itself. The audio system 24 may also include a microphone. The microphone picks up the sound reaching itself and obtains sound data representing the picked-up sound.

[0047] The WLAN (Wireless Local Area Network) card 25 connects to the wireless LAN and performs data communication with other devices directly or indirectly connected to the wireless LAN. The wireless LAN can transmit and receive various data between devices according to a specified wireless communication method (e.g., IEEE802.11).

[0048] The USB connector 26 is a connector for connecting to peripheral devices to input and output data according to the USB (Universal Serial Bus) standard.

[0049] Regardless of the system state of the main system, the EC 31 monitors the operating environment and controls the states of various devices (peripheral devices, sensors, etc.). The EC 31 independently includes a processor, a memory, and input / output terminals and is configured as a microcomputer. In the EC 31, the input / output terminals are used to connect an input device 32, a power supply circuit 33, a power button 36, a lid sensor 42, an acceleration sensor 44, etc.

[0050] The input device 32 detects the user's operation and outputs an operation signal corresponding to the detected operation to the EC 31. The above-mentioned touchpad 32t and keyboard 32k belong to the input device 32. A touch sensor may also be included in the input device 32. The touch sensor may coincide with the display 14 and be configured as a touch panel.

[0051] The power supply circuit 33 converts the voltage of the DC power supplied from an external power supply via the AC adapter 48 or from the battery 34 into the voltage required for the operation of each device constituting the information processing device 1, and supplies the power with the converted voltage to the device at the supply destination. The power supply circuit 33 controls whether power supply to each device of the information processing device 1 is required according to the control of the EC 31. The power supply circuit 33 includes: a converter that converts the voltage of the power supplied to itself, and a charge / discharge unit that charges the power with the converted voltage into the battery 34. The charge / discharge unit charges the remaining power that is not consumed by each device in the power supplied from the AC adapter 48 into the battery 34. When power is not supplied from the AC adapter 48, or when the power supplied from the AC adapter 48 is insufficient for the required power, the power discharged from the battery 34 is supplied to each device via the converter. Among the power supply destinations, in addition to the system devices, there are peripheral devices represented by the display 14 and the EC 31.

[0052] The power supply circuit 33 is electrically connected to the power supply terminal provided at the insertion port 48o. DC power is supplied from the AC adapter 48 assembled in the insertion port 48o to the power supply circuit 33 via the power supply terminal. The power supply circuit 33 may also include a voltage sensor that detects the voltage of the power supply terminal, and outputs a voltage detection signal indicating the detected voltage to the EC 31. The EC 31 can determine which of the external power supply and the battery 34 is the power supply type (sometimes referred to as "power supply type" in this application) for supplying power to the information processing device 1 based on the voltage detection signal input from the voltage sensor. Which of the power supplied from the external power supply and the power supplied from the battery 34 is consumed is based on whether the AC adapter 48 is assembled in the insertion port 48o in a state where DC power can be supplied. The EC 31 can determine whether the power supply type is an external power supply or the battery 34, for example, by whether the voltage indicated by the voltage detection signal is higher than a specified voltage reference value. The EC 31 notifies the determined power supply type to the main system 110.

[0053] The battery 34 is stored inside the housing 102. The battery 34 is charged with the power supplied from the AC adapter 48 by the charge / discharge unit of the power supply circuit, and supplies the charged power to each device via the converter. The battery 34 has a rechargeable secondary battery. The battery 34 has, for example, a lithium-ion battery.

[0054] Whenever the power button 36 receives a press operation, it controls either power-on (Power ON) or power-off (Power OFF) as the power supply state of the main system 110 of the information processing device 1. When receiving a press operation, the power button 36 outputs a press signal indicating the press to the EC 31.

[0055] The lid sensor 42 detects the open / closed state of the casings 102 and 104. The lid sensor 42 generates a detection signal indicating the detected open / closed state and outputs it to the EC 31. The EC 31 determines the open / closed state based on the detection signal input from the lid sensor 42. For example, when the lid sensor 42 is a magnetic sensor, the EC 31 can determine whether the casings 102 and 104 are closed by checking whether the intensity of the magnetic field indicated by the detection signal exceeds a specified intensity threshold. The EC 31 notifies the main system of the open / closed state information indicating the determined open / closed state. In the following description, the state where the casings 102 and 104 are open may be referred to as the "open state" (lid open), and the state where the casings 102 and 104 are closed may be referred to as the "closed state" (lid closed). The EC 31 notifies the determined open / closed state to the main system 110 via the chipset 21. The open / closed state notified to the main system is sometimes used for controlling the system state.

[0056] The acceleration sensor 44 detects the acceleration applied to itself and outputs an acceleration signal indicating the detected acceleration to the EC 31. The acceleration sensor 44 is, for example, a three-axis sensor. The three-axis sensor can detect the acceleration in the axial directions orthogonal to each other in a three-dimensional space. The EC 31 outputs the acceleration signal input from the acceleration sensor 44 to the main system. The acceleration notified to the main system is also sometimes used for controlling the system state.

[0057] Next, a functional structure example of the information processing apparatus 1 according to the present embodiment will be described. Figure 3 It is a schematic block diagram showing a functional structure example of the information processing apparatus 1 according to the present embodiment.

[0058] The main system 110 of the information processing apparatus 1 includes a setting processing unit 112, an operation mode control unit 114, a usage state detection unit 116, and a brightness control unit 118.

[0059] The setting processing unit 112 sets various parameters in the main system according to user operations. The setting processing unit 112 causes a setting screen to be displayed on the display 14. The setting screen is configured to include the parameters that can be set and the set values of the parameters set at that time. The setting processing unit 112 selects the power control mode indicated by the operation signal input via the EC 31 from among the predetermined multi-level power control modes. The setting processing unit 112 notifies the selected power control mode to the brightness control unit 118.

[0060] The main system 110 operates according to the selected power control mode. The power consumption of the main system 110 varies for each power control mode. Each power control mode is defined using parameters related to the power consumption of the main system 110. The parameters related to the power control mode include the rated power of the CPU (e.g., PL1: Power Limit 1). Generally, the more the rated power, the more the power consumption, and thus the higher the processing capacity of the main system 110. On the other hand, the less the rated power, the less the power consumption, and thus the lower the processing capacity of the main system 110.

[0061] The setting processing unit 112 may also include power supply type information indicating the power supply type notified from the EC 31 to form a boot screen, and cause the formed boot screen to be displayed on the display 14.

[0062] Figure 4 FIG. is an example of the setting screen PS01 and the boot screen TB01 according to the present embodiment. The illustrated setting screen PS01 and boot screen TB01 each have an elongated shape with a horizontal width larger than the vertical height. The setting screen PS01 and the boot screen TB01 may also be arranged at a position adjacent to the bottom edge of the display area of the display 14. The setting screen PS01 constitutes a slider for selecting one power control mode from three levels of power control modes through user operation. As the three levels of power control modes, the efficiency mode (Best Power Efficient), the balanced mode (Balanced), and the performance mode (Best Performance) are arranged in order from left to right. The efficiency mode among the three levels of power control modes is the power control mode with the least rated power, and the rated power increases in the order of the efficiency mode, the balanced mode, and the performance mode. The boot screen TB01 is configured as a task bar, and an icon formed by patterning a set of a power plug and a battery is shown in the central part thereof. Through this display, it is shown that the power supply type is an external power supply.

[0063] The operation mode control unit 114 controls the system state (operation mode) of the main system 110 based on the usage status of the information processing device 1. In the operation mode control unit 114, the transition conditions from the source system state 1 to the destination system state 2 are preset for each group of a certain system state 1 and another system state 2. The operation mode control unit 114 refers to the transition conditions from the current time point's system state 1 to the system state 2, and based on the usage status of the information processing device 1, when the current time point's operation state or usage environment satisfies the transition conditions to the system state 2, it causes the current time point's system state 1 to transition to the system state 2. The operation mode control unit 114 notifies the system state determined by the control to the EC 31 via the chipset 21.

[0064] The system states include, for example, the normal mode, modern standby, hibernation, and power off. The normal mode, hibernation, and power off respectively correspond to the S0 state, S4 state, and S5 state in the system states defined by the ACPI (Advanced Configuration and Power Interface) standard. Modern standby is a standby state with lower power consumption than the normal mode and is a state that extends the S0 state. Modern standby is sometimes denoted as the S0ix state or the S0i3 state. Generally speaking, the power consumption decreases in the order of the normal mode, modern standby, hibernation, and power off.

[0065] The normal mode is the normal system state. In the normal mode, the display 14 operates. When the system state for displaying the display screen according to the display data output from the main system 110 is the normal mode, the brightness control unit 118 performs the brightness control described below. In other system states, the screen display of the display 14 is stopped, so the brightness control unit 118 does not perform the brightness control of the display 14.

[0066] Next, an example of the transition conditions of the system state will be described. The transition conditions from the normal mode to modern standby include, for example, the situation where the following conditions are detected: when the display screen has not changed for a certain period of time (e.g., 3 to 10 minutes) or more and no operation signal from the input device 32 is detected, when there is no application indicating startup, when the opening / closing state of the enclosures 102 and 104 changes from the open state to the closed state, when the acceleration indicated by the acceleration signal from the acceleration sensor 44 is greater than the specified reference value, etc. In modern standby, in addition to the EC 31, some peripheral devices such as the memory 23 and the WLAN card 25 can also continue to operate. In addition, the main system 110 can also wait for an operation signal from the input device 32 via the EC 31 and the chipset 21.

[0067] The transition conditions from modern standby to the normal mode include, for example: when an operation signal is input from the input device 32, when a press signal is input from the power button 36, when the opening / closing state of the enclosures 102 and 104 changes from the closed state to the open state, when the state where the acceleration indicated by the acceleration signal from the acceleration sensor 44 is lower than the specified reference value continues for a specified duration or more, etc.

[0068] Among the transition conditions from modern standby to hibernation, in addition to the case where the measured power consumption value becomes less than or equal to the power consumption reference value, there are also cases where modern standby continues for a certain period of time (e.g., 10 to 30 minutes) or more, the time at that point reaches the preset standby time, when sleep is indicated by an operation signal, and when the remaining amount of the battery 34 becomes less than or equal to the specified limit value, etc.

[0069] Among the transfer conditions from the normal mode or modern standby to power-off are cases such as when a press signal is input from the power button 36 or when a specified request is issued from the OS.

[0070] In addition, in the modern standby or power-off state, the operation of the main system 110 stops. Therefore, the operation mode control unit 114 has nothing to do with the transfer from the modern standby or power-off state to the normal mode. The transfer from the power-off state to the normal mode is executed through the startup process based on the BIOS. In the transfer from modern standby to the normal mode, the EC 31 resumes power supply to the main system 110, loads the image data stored in the memory 23 into the main memory 12, and then starts the OS.

[0071] The usage detection unit 116 detects the usage status of the information processing device 1. The usage detection unit 116 detects the usage status related to the control of the system state and the usage status related to the brightness control or its change. The usage detection unit 116 includes, for example: the input of an operation signal from the input device 32 via the EC 31, the notification of the power type from the EC 31, the input of a press signal from the power button 36 via the EC 31, the notification of the opening and closing state information of the casings 102 and 104, the input of an acceleration signal from the acceleration sensor 44 via the EC 31, the change of the display data output to the display 14, etc. Among them, the operation signal, the press signal, the opening and closing state information, the acceleration signal, etc. are used for the control of the system state. The operation signal and the power type information, etc. are used for the brightness control.

[0072] The brightness control unit 118 controls the brightness of the display screen displayed on the display 14 according to the usage status of the information processing device 1. The brightness control unit 118 determines the reference value of the brightness setting value based on the power type notified from the usage detection unit 116. When the power type is the battery 34, the brightness control unit 118 determines a value lower than the reference value of the brightness setting value in the case where the power type is an external power supply. The reason is that when the power type is the battery 34, compared with the case of an external power supply, the display screen displayed on the display 14 is darker, and the necessity of reducing power consumption is high.

[0073] Whenever the brightness control unit 118 sets the brightness setting value, it notifies the set brightness setting value to the display 14. The brightness control unit 118 displays the screen with the brightness corresponding to the brightness setting value by notifying the brightness setting value.

[0074] The brightness control unit 118 may further determine a reference value of the brightness setting value in consideration of the power control mode notified from the setting processing unit 112. For a power control mode with a larger rated power, the brightness control unit 118 sets a larger value as the reference value of the brightness setting value. The reason is that when improving the processing ability of the main system 110, it is expected that the display 14 displays a high-brightness screen. Therefore, in the brightness control unit 118, a brightness setting table indicating the default brightness setting value is preset for each group of the power control mode and the power supply type. The brightness control unit 118 refers to the brightness setting table, determines the brightness setting value corresponding to the group of the indicated power control mode and the notified power supply type, and sets the determined brightness setting value in the display 14.

[0075] Figure 5 FIG. is a diagram showing a setting example of the brightness setting table according to the present embodiment. The brightness setting table is a data table indicating the default brightness setting value that is the reference value of the brightness setting value for each group of the power control mode and the power supply type. The higher the rated power of the power control mode, the higher the value is set as the default brightness setting value, and compared with the case where the power supply type is the battery 34, in the case of an external power supply, a higher value is set as the default brightness setting value. In Figure 5 each row represents the power supply type, and each column represents the power control mode. DC described in the column of the power supply type indicates a battery, and AC indicates an external power supply. As the power control mode, an efficiency mode, a balanced mode, and a performance mode are proposed. The reference values in the case where the power supply type is a battery are set as LD1 < LD2 < LD3. The reference values in the case where the power supply type is an external power supply are set as LA1 < LA2 < LA3. For each power control mode, the reference values are set as LD1 < LA1, LD2 < LA2, and LD3 < LA3. Among them, for the performance mode, it may be set that LD3 = LA3.

[0076] Depending on the usage environment and the user's preference, sometimes a brightness higher than that determined based on one or both of the power supply type and the power control mode is desired. For example, during the day outdoors, it is bright around, so it is desired to brighten the screen shown on the display.

[0077] Therefore, the brightness control unit 118 may also adjust the brightness setting value according to a specified operation. In the present application, the brightness setting value adjusted according to the user's operation is sometimes referred to as the "user setting value". For example, every time the brightness control unit 118 detects an operation on a specified key on the keyboard 32k (for example, pressing the F6 key), the brightness control unit 118 increases the brightness setting value by a specified increase amount. Among them, when the brightness setting value reaches a preset maximum value, the brightness control unit 118 does not perform further processing to increase the brightness setting value even if the operation is detected.

[0078] The brightness control unit 118 monitors the power supply type notified by the usage detection unit 116. When the power supply type changes from an external power supply to the battery 34 and the brightness setting value at that time is greater than the reference value of the brightness setting value when the power supply type is the battery 34, the brightness setting value at that time is decreased. Here, the decreased brightness setting value is set to a value greater than the reference value. In addition, the process of decreasing the brightness setting value to a value between the user setting value and the reference value when the power supply is the battery 34 when the power supply type is switched from an external power supply to the battery is sometimes referred to as "brightness reduction processing".

[0079] In addition, when the user notices the decrease in brightness caused by the decrease in the brightness setting value, the user may urge an operation to increase the brightness setting value again. If the brightness increases due to the operation, the power consumption increases again. Therefore, the change amount of the brightness setting value when the power supply type changes from an external power supply to the battery 34 can also be set to such an extent that the user does not notice the brightness change. For example, it can be about several percent to 10% of the value range of the brightness setting value.

[0080] The brightness control unit 118 can also decrease the brightness setting value by a certain change amount each time the notified power supply type changes from an external power supply to the battery 34 until it reaches the reference value corresponding to the battery 34.

[0081] The brightness control unit 118 can also decrease the change amount of the brightness setting value caused by the change of the power supply type to the battery 34 as the brightness setting value becomes smaller. For example, the brightness control unit 118 can also decrease the brightness setting value at that time by a certain change rate (for example, 5 to 10%) each time the power supply type changes to the battery 34. When the brightness setting value is decreased at a certain change rate, the change amount of the brightness setting value decreases with each repetition of the decrease of the brightness setting value.

[0082] Next, the relationship between the brightness setting value set by the brightness control unit 118 and the brightness of the screen displayed on the display 14 will be described. The brightness setting value can be the brightness itself as a physical quantity, or an index value uniquely corresponding to the brightness. The brightness setting value can also be normalized to a real value that is easy for the user to recognize. The brightness setting value becomes a real number within a predetermined value range (for example, 0% to 100%). The larger the brightness setting value, the higher the brightness. 0% and 100% correspond to the minimum and maximum values of the brightness. As the brightness setting value, values predefined by software such as the OS and the device driver of the display 14 can also be used. The brightness control unit 118 can also display a setting screen including screen components such as a dial and a slider on the display 14 based on this software, and the brightness setting value can be arbitrarily set according to the operation.

[0083] As described above, the display 14 supplies drive power to each pixel, and the drive power has an intensity obtained by multiplying the intensity corresponding to the signal value shown in the display data by a gain corresponding to the brightness setting value. As Figure 6 illustrated, there is a tendency that the higher the brightness setting value, the higher the brightness of the displayed image. In addition, the higher the brightness setting value, the higher the ratio of the increase in brightness to the increase in the brightness setting value.

[0084] Next, an example of the transition of the brightness setting value based on changes in the usage situation will be described using Figure 6 As an example, the transition of the brightness setting value based on changes in the usage situation will be described.

[0085] At the beginning of the use of the information processing apparatus 1, the brightness control unit 118 sets a reference value of the brightness setting value corresponding to the group of the power control mode and the power supply type as the initial value LD of the brightness setting value. The display screen is displayed on the display 14 with the brightness determined according to the set brightness setting value.

[0086] Here, assuming that the user wants to brighten the display screen, a case where a prescribed key operation is performed (a. key operation) is considered. Each time the brightness control unit 118 detects a key operation, the brightness setting value is increased by a prescribed increment. With this increase in the brightness setting value, the brightness of the display screen displayed on the display 14 increases. Each time a key operation is detected, the brightness setting value is increased until the maximum value LMAX is reached.

[0087] Then, assuming that the user disconnects the AC adapter 48 from the information processing apparatus 1 (b. AC / DC switching). At this time, the disconnection of the AC adapter 48 is detected in the EC 31, and the change in the power supply type from the external power supply to the battery 34 is detected. Each time the brightness control unit 118 detects the change in the power supply type from the external power supply to the battery 34, the brightness setting value decreases at a certain rate of change. The brightness of the display screen decreases as the brightness setting value decreases.

[0088] When the main system 110 stops operating, that is, when the system state changes from the normal mode to the power-off state, the brightness control unit 118 may also save the brightness setting value at that time in the memory 23. Further, when the main system 110 restarts operating, the brightness control unit 118 may also read out the brightness setting value saved in the memory 23. The brightness control unit 118 may also apply the read-out brightness setting value as the brightness setting value at that time and notify it to the display 14. Thereby, the display 14 can be used with the brightness indicated by the brightness setting value before the operation stop.

[0089] In addition, the brightness control unit 118 may also update the brightness setting value to a reference value corresponding to the group of the power control mode and the power supply type each time the power control mode notified from the setting processing unit 112 is changed.

[0090] In addition, when the main system 110 stops operating, the brightness control unit 118 may also save the brightness setting value in the memory 23 in correspondence with the set of the power control mode and the power supply type at that time point. The brightness control unit 118 may also read out from the memory 23 the brightness setting value corresponding to the set of the changed power control mode and brightness setting value whenever one or both of the power control mode and the brightness setting value are changed. Thereby, the display 14 can be used at the brightness indicated by the brightness setting value corresponding to the set of the power control mode and the brightness setting value.

[0091] Next, an example of the brightness control according to the present embodiment will be described. Figure 7 It is a flowchart showing an example of the brightness control according to the present embodiment. Among them, Figure 7 It shows the process from reading out the previously saved brightness setting value until the brightness setting value is reduced to the reference value (default value) due to the change of the power supply type to the battery 34, or until the increase of the brightness setting value is instructed by the user operation. The user operation is a display based on the user's intention, avoiding the automatic setting contrary to the intention display.

[0092] (Step S102) The brightness control unit 118 reads out the brightness setting value last saved in the memory 23 in advance, and sets the read brightness setting value to the display 14. In the reading of the brightness setting value, the brightness control unit 118, for example, calls up the driver software and communicates with the OS.

[0093] (Step S104) The usage detection unit 116 monitors the usage status (user scenario) of the information processing apparatus 1. When the system state is in the S0 state, the usage detection unit 116 proceeds to the process of step S106.

[0094] (Step S106) The brightness control unit 118 determines whether the brightness setting value set at that time point is greater than the reference value and the power supply type is changed from the external power supply to the battery 34 (AC / DC switching). The brightness control unit 118 refers to the brightness setting table and determines the reference value (default value) of the brightness setting value corresponding to the power supply type and the power control mode set at that time point. When it is determined that the brightness setting value is greater than the reference value and the power supply type is changed to the battery 34 (Yes in step S106), the process proceeds to step S108. When it is determined that the brightness setting value is equal to or less than the reference value or the power supply type is not changed to the battery 34 (No in step S106), the process returns to the process of step S104.

[0095] (Step S108) The brightness control unit 118 reduces the brightness setting value at that time point by a prescribed change amount.

[0096] (Step S110) The brightness control unit 118 monitors whether an increase in the brightness setting value is indicated by a prescribed user operation. When an increase in the brightness setting value is indicated (Yes in Step S110), the brightness control unit 118 increases the brightness setting value by a prescribed increase amount, and sets the increased brightness setting value to the display 14. Then, the Figure 7 processing ends. Among them, when the brightness setting value reaches the maximum value LMAX, the brightness setting value is not changed. Then, the processing of Step S104 may also be entered.

[0097] When an increase in the brightness setting value is not indicated (No in Step S110), the processing of Step S112 is entered.

[0098] (Step S112) The brightness control unit 118 determines whether the brightness setting value has reached a prescribed reference value (default value). When it is determined that it has reached (Yes in Step S112), the Figure 7 processing ends. When it is determined that it has not reached (No in Step S112), the brightness control unit 118 decreases the brightness setting value by a prescribed change amount, and sets the decreased brightness setting value to the display 14. Then, the processing returns to Step S104.

[0099] <Second Embodiment>

[0100] Next, the second embodiment of the present application will be described mainly with differences from the first embodiment. Matters not specially described are the same as those in the first embodiment, and the description thereof is incorporated by reference.

[0101] The brightness control unit 118 according to this embodiment also monitors the power supply type notified from the usage state detection unit 116. When the power supply type changes from an external power supply to the battery 34 and the brightness setting value at that time is greater than the reference value of the brightness setting value when the power supply type is the battery 34, the brightness setting value at that time is decreased by a prescribed change amount (decrease amount).

[0102] The brightness control unit 118 according to this embodiment reduces the brightness setting value by changing the power supply type to the battery 34, and then increases the brightness setting value at that time when the power supply type changes from the battery 34 to an external power supply. In this way, when the brightness setting value is smaller than the reference value in the case of an external power supply as the power supply type, when the power supply type is switched from the battery 34 to an external power supply, the process of increasing the brightness setting value to a value between the current brightness setting value and the reference value in the case of an external power supply as the power supply type is sometimes referred to as "brightness increase process". Among them, the increase amount of the brightness setting value caused by the change of the power supply type to an external power supply can be made equal to the decrease amount of the brightness setting value caused by the change of the power supply type to the battery 34, but the increase amount of the brightness setting value caused by the change of the power supply type to an external power supply can also be made smaller than the decrease amount of the brightness setting value caused by the change of the power supply type to the battery 34.

[0103] For example, when the decrease amount of the brightness setting value when changing the power supply type to the battery 34 is set to a constant value, the brightness control unit 118 can also determine a value smaller than the absolute value of the decrease amount of the brightness setting value as the increase amount of the brightness setting value when changing the power supply type to an external power supply.

[0104] When the smaller the brightness setting value, the smaller the decrease amount of the brightness setting value caused by the change of the power supply type to the battery 34, the brightness control unit 118 can also make the increase amount of the brightness setting value caused by the change of the power supply type to an external power supply smaller when the brightness setting value is smaller.

[0105] When the decrease amount of the brightness setting value caused by the change of the power supply type to the battery 34 is determined based on a certain reduction rate of the brightness setting value at that time, as the increase amount of the brightness setting value caused by the change of the power supply type to an external power supply, the brightness control unit 118 is determined based on a certain increase rate of the brightness setting value at that time. Among them, the increase rate of the brightness setting value is set to a value smaller than the reduction rate of the brightness setting value. For example, when the reduction rate of the brightness setting value is set to 10 - 15%, the increase rate of the brightness setting value can be set to 5 - 8%.

[0106] Next, an example of the change of the brightness setting value based on the change of the usage situation will be described. Among them, the increase of the brightness setting value based on the key operation and the decrease of the brightness setting value based on the AC / DC switching are the same as the example of Figure 8 And the example of Figure 8 is the same.

[0107] In this situation, assume that the user assembles the AC adapter 48 into the insertion port 48o of the information processing apparatus 1 (c.DC / AC switching). At this time, the assembly of the AC adapter 48 is detected in the EC 31, and the change in the power supply type from the battery 34 to an external power supply is detected. When the change in the power supply type to the battery 34 causes a decrease in the brightness setting value and then the change in the power supply type from the battery 34 to an external power supply is detected, the brightness control unit 118 increases the brightness setting value at an increase rate smaller than the decrease rate used for the decrease. The brightness control unit 118 sets the increased brightness setting value to the display 14.

[0108] An example of the brightness control according to the present embodiment will be described. Figure 9 It is a flowchart showing an example of the brightness control according to the present embodiment. Figure 9 The processing of includes the processing of steps S102 to S112 and the processing of steps S206 and S208. The processing of steps S102 to S112 is the same as the processing of steps S102 to S112 in the Figure 7 processing, so the description thereof is incorporated by reference. Among them, in step S106, when it is determined that the brightness setting value is equal to or less than the reference value or the power supply type has not been changed to the battery 34 (step S106 NO), the processing of step S206 is entered.

[0109] (Step S206) The brightness control unit 118 determines whether the brightness setting value set at this time is obtained by decreasing due to the change in the power supply type from an external power supply to the battery 34 (AC / DC switching) and whether the power supply type has been changed from the battery 34 to an external power supply (DC / AC switching). When it is determined that the brightness setting value has decreased due to the change in the power supply type from an external power supply to the battery 34 and the power supply type has been changed to an external power supply (step S206 YES), the processing of step S208 is entered. When it is determined that the brightness setting value is not a value decreased due to the change in the power supply type from an external power supply to the battery 34, or when it is determined that the power supply type has not been changed to an external power supply (step S206 NO), the processing of step S104 is entered.

[0110] (Step S208) The brightness control unit 118 increases the brightness setting value at this time by an increase amount smaller than the decrease amount related to the decrease in the brightness setting value. Then, the processing of step S110 is entered.

[0111] <Third Embodiment>

[0112] Next, the third embodiment of the present application will be described mainly with the differences from the first embodiment. Matters not specifically described are the same as those in the first embodiment, and the description thereof is incorporated by reference. Among them, the differences described below can also be applied to the second embodiment.

[0113] When changing the usage status of the change information processing device 1, the brightness control unit 118 attaches a brightness setting value to the changed usage status and stores it in the storage 23. The information on the stored usage status forms a setting history. In the setting history, there is sometimes information on the brightness setting value after the operation corresponding to an operation (for example, a key operation) for indicating an increase in brightness.

[0114] The brightness control unit 118 uses the setting history to derive the probability of performing a specified operation for each brightness setting value. There is a tendency that the smaller the brightness setting value, the higher the derived probability, and the larger the brightness setting value, the lower the derived probability. The brightness control unit 118 can also use a specified mathematical model to determine the brightness setting value for which the probability becomes below a specified probability threshold (for example, 10 to 30%) as the reference value (default value) of the brightness setting value. The probability threshold may be set to a value closer to 0% than 100%. As the mathematical model, for example, probability distribution functions such as the error function and the sigmoid function can be applied. These probability distribution functions provide the probability that asymptotically approaches the maximum value 1 as the input value increases as the output value, and provide the probability that asymptotically approaches the minimum value 0 as the input value decreases as the output value. Here, the brightness control unit 118 performs regression analysis based on the probability derived for each brightness setting value, and determines a probability distribution function that can calculate the probability for any brightness setting value within a specified value range. The brightness control unit 118 can use the obtained probability distribution function to search for the brightness setting value that provides the specified probability threshold as the reference value.

[0115] Next, an explanation will be given of the setting based on the reference value of the operation. Among them, the increase in the brightness setting value based on the key operation and the decrease in the brightness setting value based on the AC / DC switch are Figure 10 the same as the example of Figure 8 Assume that the initial brightness setting value is LD.

[0116] Each time the brightness control unit 118 detects a specified key operation, it increases the brightness setting value by a specified increase amount (a. key operation). When the power supply type changes from an external power supply to the battery 34 and the brightness setting value at that time is larger than the reference value of the brightness setting value when the power supply type is the battery 34, the brightness control unit 118 decreases the brightness setting value at that time (b. AC / DC switch). In this way, each time the brightness setting value changes along with the change in the usage status, the brightness control unit 118 records the brightness setting value in the setting history corresponding to the usage status.

[0117] Among the various pieces of information included in the setting history, there are cases where the set brightness setting value is associated with a specified key operation and cases where it is not. The brightness control unit 118 refers to the setting history, aggregates the occurrence frequency and the frequency associated with the key operation for each brightness setting value, and calculates the ratio of the latter to the former as the probability of performing the key operation. The brightness control unit 118 determines the brightness setting value at which the probability calculated based on a specified mathematical model becomes the specified probability threshold as the reference value in the case where the power supply type is a battery (d. reference value of the brightness setting value learned based on the key operation). Since the brightness of the display screen is sufficient, this brightness setting value can be regarded as a value that does not require increasing the brightness through key operation. The brightness control unit 118 sets the brightness setting value LD' obtained based on the setting history to this reference value (e. adjust the brightness setting value based on the learned reference value). In the case where the power supply type is the battery 34, the brightness control unit 118 uses the set reference value as the minimum value of the brightness setting value. When the power supply type changes from an external power supply to the battery 34 and the brightness setting value at that time is greater than the newly set reference value, the brightness control unit 118 decreases the brightness setting value at that time. Therefore, when the brightness setting value at that time becomes less than or equal to the newly set reference value, even if the power supply type changes from an external power supply to the battery 34, the brightness control unit 118 does not decrease this brightness setting value.

[0118] In addition, the brightness control unit 118 may also refer to the setting history to determine the reference value of the brightness setting value for each power control mode. The reason is that the desired brightness of the display screen may be different for each power control mode. The brightness control unit 118 may also update the reference value corresponding to the group of this power control mode and the battery as the power supply type in the brightness setting table to the reference value determined for a certain power control mode.

[0119] The brightness control unit 118 may also wait for an operation signal indicating the power control mode from the input device 32. The brightness control unit 118 refers to the brightness setting table and determines the reference value corresponding to the group of the power control mode indicated by the input operation signal and the power supply type at that time. The brightness control unit 118 sets the determined reference value to the display 14.

[0120] As described above, the information processing apparatus 1 according to the present embodiment includes: a power supply circuit 33 that supplies power from a power source; and a brightness control unit 118 that controls the brightness of the display 14. The brightness control unit 118 has a first reference value when the power source type is an external power source and a second reference value that is smaller than the first reference value and when the power source type is the battery 34, as reference values for the brightness setting value, that is, the brightness setting value. The brightness control unit 118 sets the brightness setting value to a user-specified user setting value according to a user operation. When the power source type is switched from the external power source to the battery 34 while the user setting value is larger than the second reference value, the brightness control unit 118 performs a process of reducing the brightness setting value to a value between the user setting value and the second reference value, that is, the brightness reduction process.

[0121] According to this configuration, the brightness setting value increased according to an operation is reduced when the power source type is switched to the battery 34. Even if an operation mainly for reducing the brightness is not performed, the brightness of the display 14 is reduced, so that the overall power consumption of the information processing apparatus 1 is reduced. At the same time, by making the brightness setting value larger than the second reference value when the power source type is the battery 34, it is possible to reduce the possibility of an operation related to increasing the brightness by making the user notice the reduction in brightness.

[0122] In the brightness reduction process, the brightness control unit 118 reduces the brightness setting value from the user setting value by a prescribed change amount.

[0123] According to this configuration, when the power source type is switched to the battery 34, the brightness setting value is reduced by the change amount from the user setting value at that time. Therefore, every time the power source type is switched to the battery 34, the brightness of the display 14 is reduced by an amount corresponding to the change amount of the brightness setting value.

[0124] The brightness control unit 118 may make the change amount of the brightness setting value smaller in the brightness reduction process as the user setting value is lower.

[0125] According to this configuration, the lower the brightness of the display 14, the more physically the change amount of the brightness corresponding to the change amount of the brightness setting value is reduced. Therefore, considering the visual characteristic that the change in brightness is more easily perceived as the brightness is lower, the change in visual brightness in each repetition of the brightness reduction process is close to an equal interval, so that a more natural change in brightness is perceived.

[0126] In a power control mode in which the rated power of the main system 110 is larger, the reference value of the brightness setting value when the power source type is the battery 34 is larger, and the brightness control unit 118 may also set the brightness setting value to a reference value corresponding to the set of the selected power control mode and the power source type.

[0127] According to this structure, in a power control mode with a higher rated power of the main system 110, the brightness setting value is set to be larger. This can respond to the expectation that in a power control mode with a higher rated power, the processing ability of the main system 110 is higher and the brightness of the display 14 is larger.

[0128] The brightness control unit 118 may also save the brightness setting value when the main system 110 stops operating, and apply the saved brightness setting value to the display 14 when the main system 110 restarts operating.

[0129] According to this structure, after the main system 110 restarts operating, the brightness setting value applied before the operation stopped is applied. Since the brightness preferred before the operation stop is applied after the restart, there is no need for an operation to obtain the preferred brightness after the restart.

[0130] In addition, various design matters such as various setting information and parameters related to the above processing are not limited to the illustrated content, and may also vary according to various requirements such as the capabilities of the main system 110 and the display 14. For example, the number of levels of the power control mode is not limited to three levels, and may also be two levels or four levels or more.

[0131] As described above, the embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the specific structure is not limited to the above embodiments, and also includes designs within the scope not departing from the gist of the present invention. The various structures described in the above embodiments can be arbitrarily combined.

Claims

1. An information processing device comprising: a power supply circuit that supplies power from a power supply; and Brightness control unit, controls the brightness of the display, The brightness control unit has a reference value when the power source is a battery, which is used as a reference value of the brightness setting value, that is, the brightness setting value. setting the brightness setting value to a user setting value specified by the user according to the user's operation, In a state where the user setting value is greater than a reference value when the power source type is a battery, when the power source type is switched from an external power source to a battery, a brightness reduction process is performed to reduce the brightness setting value to a value between the user setting value and the reference value when the power source type is a battery.

2. The information processing device according to claim 1, wherein: The brightness control unit reduces the brightness setting value from the user setting value by a predetermined amount of change in the brightness reduction process.

3. The information processing device according to claim 2, wherein: The brightness control section reduces the amount of change in the brightness setting value in the brightness reduction process as the user setting value is lower.

4. The information processing device according to claim 1, wherein: The larger the rated power of the main system is, the larger the reference value is when the power source is a battery. The brightness control unit sets the brightness setting value to a reference value corresponding to a selected combination of the power control mode and the power type.

5. The information processing device according to claim 1, wherein: The brightness control unit saves the brightness setting value when the main system stops operating. The saved brightness setting value is applied to the display when the main system resumes operation.

6. A control method, a control method of an information processing device, the information processing device comprising a power supply circuit for supplying power from a power supply and a brightness control unit for controlling the brightness of a display, wherein: The information processing device includes a reference value when the power source type is a battery, which is used as a reference value of the brightness setting value, that is, the brightness setting value. setting the brightness setting value to a user setting value specified by the user according to the user's operation, In a state where the user setting value is greater than a reference value when the power source type is a battery, when the power source type is switched from an external power source to a battery, a brightness reduction process is performed to reduce the brightness setting value to a value between the user setting value and the reference value when the power source type is a battery.

Images