Indication device

Abstract

To resolve a shortage of power supplied to a second external device.SOLUTION: A display unit comprises: a plurality of connection means; a connection detection unit that detects that external devices are connected to the connection means; a negotiation unit that performs a negotiation related to power with the external devices connected to the connection means; a power output unit that, based on a result of the negotiation performed by the negotiation unit, outputs power required for the external devices connected to the connection means from the connection means to which the external device are connected; and a pass-through control unit that outputs the power input from the first connection means to which the first external device is connected, from the second connection means to which the second external device is connected. When the power that can be output from the second connection means is not sufficient for the power required for the second external device, the pass-through control unit reduces the power consumption of the display unit to allow the second connection means to output the power required for the second external device.SELECTED DRAWING: Figure 3

Description

Technical Field

[0005]

[0001] The present invention relates to a display device.

Background Art

[0002] Conventionally, technologies have been devised for receiving power from an external device or supplying power to an external device via an interface such as USB (Universal Serial Bus) (see, for example, Patent Documents 1 and 2 below).

[0003] Also, conventionally, a so-called power pass-through technology has been devised that uses such a technology to supply power supplied from a first external device connected to one interface to a second external device connected to another interface.

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, since the conventional power pass-through technology also consumes the power supplied from the first external device in the device itself, especially when the amount of power supplied from the first external device is small, there is a shortage of power that can be output from other interfaces, and there is a risk that the power required for the second external device cannot be supplied (that is, the second external device cannot be driven).

[0005] An object of the present invention is to improve the shortage of power supplied to a second external device when supplying the power supplied from a first external device to the second external device in order to solve the problems of the above-described conventional technology.

Means for Solving the Problems

[0006] To solve the above-mentioned problems, a display device according to one embodiment includes a plurality of connection means, a connection detection unit that detects when an external device is connected to the connection means, a negotiation unit that negotiates power with the external device connected to the connection means, a power output unit that outputs the power required by the external device connected to the connection means from the connection means to which the external device is connected, based on the negotiation result by the negotiation unit, and a pass-through control unit that outputs power input from the first connection means to which the first external device is connected from the second connection means to which the second external device is connected, wherein the pass-through control unit controls the power output of the display device so that the power required by the second external device can be output from the second connection means if the power that can be output from the second connection means is insufficient for the second external device. [Effects of the Invention]

[0007] According to one embodiment of the display device, when supplying power from a first external device to a second external device, it is possible to improve the shortage of power supplied to the second external device. [Brief explanation of the drawing]

[0008] [Figure 1] Block diagram showing the hardware configuration of a display device according to one embodiment. [Figure 2] Block diagram showing the hardware configuration of a video signal conversion cable according to one embodiment. [Figure 3] Block diagram showing the functional configuration of a display device according to one embodiment. [Figure 4] This figure shows an overview of power pass-through control by a display device according to one embodiment. [Figure 5] A flowchart showing an example (first example) of the processing procedure by a display device according to one embodiment. [Figure 6] This figure shows an example of message display by a display device according to one embodiment. [Figure 7] This figure shows an example of the display of the brightness setting screen by a display device according to one embodiment. [Figure 8] This figure shows an example of the display of the brightness setting screen by a display device according to one embodiment. [Figure 9] This figure shows an example of message display by a display device according to one embodiment. [Figure 10] A graph showing the relationship between the brightness setting value of the display panel and power consumption of a display device according to one embodiment. [Figure 11] A flowchart showing an example (second example) of the processing procedure using a display device according to one embodiment. [Figure 12] A flowchart showing an example (third example) of the processing procedure using a display device according to one embodiment. [Modes for carrying out the invention]

[0009] One embodiment of the present invention will be described below with reference to the drawings.

[0010] (Hardware configuration of display device 100) Figure 1 is a block diagram showing the hardware configuration of a display device 100 according to one embodiment.

[0011] The display device 100 shown in Figure 1 has a display panel 102 on the front of its housing (not shown) and is connected to an external device 10 (e.g., a laptop computer, smartphone, etc.) via a video signal conversion cable 20. By receiving a video signal from the external device 10 via the video signal conversion cable 20, it is capable of displaying an image corresponding to the video signal on the display panel 102. The display device 100 has a built-in battery 108 and is a thin, portable display device. Therefore, the display device 100 can be carried together with the external device 10 and used as an extended display for the external device 10 by connecting to the external device 10 when needed.

[0012] For example, the display device 100 can be used as an extended display for presentations at business sites by sales staff. Also, for example, the display device 100 can be used as a dual display for office work together with an external device 10 such as a PC. Further, for example, the display device 100 can be used as an extended display for video viewing or telecommuting by being connected to a smartphone used by an individual outside the office.

[0013] As shown in FIG. 1, the display device 100 includes a control unit 101, a display panel 102, a communication I / F 103 (Interface), a UI (User Interface) 104, a USB I / F (Interface) 105, a power supply unit 107, and a battery 108.

[0014] The control unit 101 controls the overall operation of the display device 100. For example, the control unit 101 is realized by a control circuit such as an IC (Integrated Circuit) including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc.

[0015] The display panel 102 displays various images (videos, still images, etc.) according to the video signal supplied from the control unit 101. As the display panel 102, for example, a liquid crystal panel, an organic EL (Electro Luminescence) panel, etc. are used.

[0016] The communication I / F 103 is an interface that controls wireless communication connection and wireless communication with the external device 10. The communication I / F 103 is wirelessly connected to the external device 10 (for example, a notebook computer, a smartphone, etc.) and performs transmission and reception (wireless communication) of control signals, video signals, etc. between the external device 10. As the wireless communication standard used by the communication I / F 103, for example, Wi-Fi, etc. are used.

[0017] UI104 is an interface that receives input from a user by being operated by the user. For example, the display device 100 includes, as UI104, a plurality of buttons provided on the side surface of the housing, the front surface of the housing, etc. These buttons are, for example, a power button, a selection button, an OK button, a back button, etc. However, not limited to this, the display device 100 may include, as UI104, other input devices (for example, a touch sensor provided overlapping the front surface of the display panel 102). For example, when UI104 is operated by a user operation, the display device 100 can perform various settings such as power on and off, brightness, and contrast.

[0018] USB I / F105 is an interface for connecting an external device 10. USB I / F105 has a USB port 105A (an example of "connection means") compliant with the USB standard, and a USB cable such as a video signal conversion cable 20 is connected to the USB port 105A. Thereby, USB I / F105 is connected to the external device 10 via the USB cable. For example, when a terminal (for example, a notebook personal computer, a smartphone, etc.) is connected as the external device 10, USB I / F105 can transmit and receive control signals, video signals, power, etc. with the terminal. Also, for example, when an external power supply is connected as the external device 10, USB I / F105 can receive power supplied from the external power supply.

[0019] Note that the display device 100 includes a plurality of USB I / F105s, and an external device 10 can be connected to each of the plurality of USB I / F10s. In the example shown in FIG. 1, the display device 100 includes two USB I / F105s. However, not limited to this, the display device 100 may include three or more USB I / F105s.

[0020] The power supply unit 107 controls the supply of power for driving each part of the display device 100. For example, if power is not supplied from an external device 10 (external power supply, terminal, etc.), or if the power supplied from the external device 10 (external power supply, terminal, etc.) is insufficient, the power supply unit 107 can supply power stored in the battery 108 to each part of the display device 100. Also, for example, if power is supplied from an external device 10 (external power supply, terminal, etc.), the power supply unit 107 can supply the power supplied from the external device 10 to each part of the display device 100. Furthermore, for example, the power supply unit 107 can pass through power supplied from one external device 10 (external power supply, terminal, etc.) connected to one USB I / F 105 and supply it to another external device 10 (terminal, etc.) connected to another USB I / F 105.

[0021] Battery 108 stores power for driving the display device 100. Various types of rechargeable secondary batteries (e.g., lithium-ion batteries, lithium polymer batteries, etc.) are used for battery 108. The display device 100 (e.g., power supply unit 107) can charge battery 108 using power supplied from an external device 10 (external power supply, terminal, etc.) connected to the USB I / F 105.

[0022] (Hardware configuration of video signal conversion cable 20) Figure 2 is a block diagram showing the hardware configuration of a video signal conversion cable 20 according to one embodiment.

[0023] As shown in Figure 2, the video signal conversion cable 20 includes an HDMI® interface 21, a signal conversion unit 22, a USB interface 23, and a power supply unit 24.

[0024] The HDMI I / F21 is an interface for connecting the video signal conversion cable 20 to an external device 10 (terminal). For example, the HDMI I / F21 is connected to the HDMI terminal of the external device 10, and can transmit and receive control signals, video signals, power, etc., between the external device 10 (terminal) and the HDMI I / F21.

[0025] The signal conversion unit 22 converts the video signal received from the external device 10 via the HDMI I / F 21 into a video signal that can be displayed by the display device 100.

[0026] The USB I / F23 is an interface for connecting the video signal conversion cable 20 to the display device 100. For example, the USB I / F23 is connected to the USB port 105A of the display device 100, and can transmit and receive control signals, video signals, power, etc., between the display device 100 and the USB I / F23.

[0027] The power supply unit 24 controls the supply of power for driving each part of the video signal conversion cable 20. For example, the power supply unit 107 can supply power received from the display device 100 via the USB I / F 23 to each part of the video signal conversion cable 20.

[0028] For example, the video signal conversion cable 20 can receive a video signal transmitted from an external device 10 via the HDMI I / F 21 and convert it into a video signal that can be displayed by the display device 100 using the signal conversion unit 22. The video signal conversion cable 20 can then output the converted video signal (i.e., a video signal that can be displayed by the display device 100) to the display device 100 via the USB I / F 23.

[0029] Furthermore, for example, if the display device 100 performs power pass-through control, the video signal conversion cable 20 can receive power supplied from the display device 100 via the USB I / F 23 and supply it to each part of the video signal conversion cable 20.

[0030] (Functional configuration of display device 100) Figure 3 is a block diagram showing the functional configuration of a display device 100 according to one embodiment. As shown in Figure 3, the display device 100 includes a connection detection unit 111, a negotiation unit 112, a power output unit 113, a pass-through control unit 114, and a display control unit 115.

[0031] The connection detection unit 111 detects when an external device 10 is connected to the USB port 105A of the USB I / F 105. For example, the connection detection unit 111 detects when an external device 10 is connected to the USB port 105A based on the resistance value of a specific terminal (e.g., the CC pin) of the USB port 105A, in accordance with the specifications of the USB standard.

[0032] The negotiation unit 112 negotiates power-related information with the external device 10 connected to the USB port 105A. For example, by negotiating with the external device 10, the negotiation unit 112 can obtain information such as the power (voltage and current) required by the external device 10 and the power (voltage and current) that can be output from the external device 10. If a video signal conversion cable 20 is connected to the USB port 105A, the negotiation unit 112 can also negotiate with the video signal conversion cable 20.

[0033] Based on the negotiation results by the negotiation unit 112, the power output unit 113 outputs the power required by the external device 10 connected to the USB port 105A from the USB port 105A to which the external device 10 is connected.

[0034] The pass-through control unit 114 outputs power input from the first USB port 105A to which the first external device 10 is connected, via the second USB port 105A to which the second external device 10 is connected, in accordance with the specifications of the USB-PD (USB Power Delivery) standard. As a result, the pass-through control unit 114 can supply power to the second external device 10 connected to the second USB port 105A and drive the second external device 10.

[0035] In this case, if the power that can be output from the second USB port 105A is less than the power required by the second external device 10 (as determined by the power information obtained from the second external device 10 by the negotiation unit 112), the pass-through control unit 114 controls the power consumption of the display device 100 so that the power required by the second external device 10 can be output from the second USB port 105A.

[0036] As a result, in one embodiment, even if the power input from the first USB port 105A is relatively small and the power that can be output from the second USB port 105A is insufficient to meet the power requirements of the second external device 10, the display device 100 can still output the power required by the second external device 10 from the second USB port 105A, thereby enabling it to drive the second external device 10.

[0037] For example, the pass-through control unit 114 reduces the power consumption of the display device 100 by lowering the upper limit of the brightness of the display panel 102 of the display device 100, thereby controlling the power required by the video signal conversion cable 20 to be supplied to the video signal conversion cable 20.

[0038] As a result, even if the power that can be output from the second USB port 105A of the display device 100 according to one embodiment is insufficient to meet the power requirements of the second external device 10, the display device 100 can output the power required by the second external device 10 from the second USB port 105A by lowering the upper limit of the brightness of the display panel 102 of the display device 100, thereby enabling the second external device 10 to be driven.

[0039] In this case, the pass-through control unit 114 may determine the amount by which the upper limit of the brightness of the display panel 102 is reduced according to the amount of power shortage required by the video signal conversion cable 20. For example, if the amount of power shortage required by the video signal conversion cable 20 is W1, the pass-through control unit 114 may determine the amount by which the upper limit of the brightness of the display panel 102 is reduced to W1 or W1+α. However, α is a predetermined margin value.

[0040] As a result, the display device 100 according to one embodiment can output the power required by the second external device 10 from the second USB port 105A without significantly reducing the upper limit of the brightness of the display panel 102.

[0041] Furthermore, for example, the pass-through control unit 114 may reduce the power consumption of the display device 100 by turning off the wireless communication function (e.g., communication I / F 103) provided by the display device 100, and control the system so that the power required by the video signal conversion cable 20 can be supplied to the video signal conversion cable 20.

[0042] As a result, even if the power that can be output from the second USB port 105A of the display device 100 according to one embodiment is insufficient to meet the power requirements of the second external device 10, the display device 100 can turn off its wireless communication function to output the power required by the second external device 10 from the second USB port 105A, thereby enabling it to power the second external device 10.

[0043] The USB-PD (USB Power Delivery) standard has the following characteristics: • Capable of supplying up to 100W (20V, 5A) of power. To achieve this, the output voltage can be varied in multiple (4 or 5) steps. Devices with multiple USB-PD compatible ports (USB Type-C ports) can receive power through one port and supply power through another port, allowing for daisy-chain power supply to downstream devices. • The connected devices can act as both power suppliers and power receivers, enabling bidirectional power supply.

[0044] The display control unit 115 can display various information on the display panel 102.

[0045] For example, the display control unit 115 can display various setting screens (such as a brightness setting screen) on the display panel 102.

[0046] Furthermore, for example, when the display control unit 115 switches the display device 100 to low brightness mode, it can display a message on the display panel 102 to notify the user that the display device 100 is being switched to low brightness mode.

[0047] Furthermore, for example, when the display control unit 115 turns off the wireless communication function of the display device 100, it can display a message on the display panel 102 to notify the user that the wireless communication function of the display device 100 has been turned off.

[0048] (Overview of power pass-through control by display device 100) Figure 4 shows an overview of power pass-through control by the display device 100 according to one embodiment.

[0049] In the example shown in Figure 4, a smartphone 12 is connected to the first USB port 105A1 of the display device 100 via a video signal conversion cable 20. As a result, the display device 100 can display video on the display panel 102 using the video signal supplied from the smartphone 12 via the video signal conversion cable 20.

[0050] Furthermore, in the example shown in Figure 4, the AC adapter 11 is connected to the second USB port 105A2 of the display device 100. As a result, the display device 100 is powered by the power supplied from the AC adapter 11, and a portion of the power supplied from the AC adapter 11 is passed through to the video signal conversion cable 20, thereby enabling the video signal conversion cable 20 to be powered.

[0051] Note that the AC adapter 11 is an example of an "external device that supplies power." Also, the video signal conversion cable 20 is an example of an "external device that receives power."

[0052] In this case, if the power that can be output from the first USB port 105A1 is less than the power required by the video signal conversion cable 20, the display device 100 can reduce its power consumption so that the power required by the video signal conversion cable 20 can be output from the first USB port 105A1.

[0053] For example, in the example shown in Figure 4(a), the power supplied from the AC adapter 11 is "15W", and the power consumption of the display device 100 is "12W". In this case, the power that can be output from the first USB port 105A1 is "3W". If the power required by the video signal conversion cable 20 is "4.5W", the display device 100 cannot output the power required by the video signal conversion cable 20, "4.5W", from the first USB port 105A1. Therefore, the video signal conversion cable 20 cannot operate, cannot convert the video signal supplied from the smartphone 12, and cannot transmit it to the display device 100.

[0054] In this case, the display device 100 reduces its power consumption, as shown in Figure 4(b), for example, by lowering the upper limit of the brightness of the display panel 102 provided by the display device 100, or by turning off the wireless communication function provided by the display device 100.

[0055] For example, in the example shown in Figure 4(b), the display device 100 reduces its power consumption to "10W". As a result, the power that can be output from the first USB port 105A1 increases to "5W". Therefore, the display device 100 can output the "4.5W" power required by the video signal conversion cable 20 from the first USB port 105A1. Consequently, the video signal conversion cable 20 becomes operational and can convert the video signal supplied from the smartphone 12 and transmit it to the display device 100.

[0056] (An example of the processing procedure by the display device 100 (Example 1)) Figure 5 is a flowchart showing an example (first example) of the processing procedure by the display device 100 according to one embodiment.

[0057] In the following explanation, "USB port 1" refers to the first USB port 105A (first connection means) provided by the display device 100, and "USB port 2" refers to the second USB port 105A (second connection means) provided by the display device 100.

[0058] Furthermore, in the following explanation, the external device 10 connected to USB port 1 is assumed to be a second external device 10 that receives power (such as a video signal conversion cable 20), and the external device 10 connected to USB port 2 is assumed to be a first external device 10 that supplies power (such as an AC adapter).

[0059] Furthermore, it is assumed that an external device 10 (such as an AC adapter) is already connected to USB port 2 before starting the series of processes shown in Figure 5.

[0060] First, the connection detection unit 111 determines whether or not an external device 10 is connected to the USB port 1 (step S501). For example, the connection detection unit 111 determines whether or not an external device 10 is connected to the USB port 1 based on the resistance value of a specific terminal (e.g., CC pin) provided on the USB port 1, in accordance with the specifications of the USB standard.

[0061] If, in step S501, it is determined that no external device 10 is connected to USB port 1 (step S501: NO), the connection detection unit 111 executes step S501 again.

[0062] On the other hand, if it is determined in step S501 that an external device 10 is connected to USB port 1 (step S501: YES), the connection detection unit 111 determines whether the external device 10 connected to USB port 1 is a sink (an external device 10 to which power is supplied) (step S502). For example, the connection detection unit 111 determines whether the external device 10 connected to USB port 1 is a sink based on the resistance value of a specific terminal (e.g., CC pin) provided by USB port 1, in accordance with the specifications of the USB standard. If a video signal conversion cable 20 is connected as the external device 10 to USB port 1, the connection detection unit 111 determines that the external device 10 connected to USB port 1 is a sink.

[0063] In step S502, if it is determined that the external device 10 connected to USB port 1 is not a sink (step S502: NO), the negotiation unit 112 negotiates with the external device 10 connected to USB port 1 in accordance with the specifications of the USB-PD standard (step S510).

[0064] Then, the power output unit 113 outputs power to the external device 10 connected to the USB port 1, or inputs power from the external device 10 connected to the USB port 1, based on the negotiation result in step S510 (step S511). After that, the display device 100 completes the series of processes shown in Figure 5.

[0065] On the other hand, if in step S502 it is determined that the external device 10 connected to USB port 1 is a sink (step S502: NO), the connection detection unit 111 determines whether or not the external device 10 is connected to USB port 2 (step S503). For example, the connection detection unit 111 determines whether or not the external device 10 is connected to USB port 2 based on the resistance value of a specific terminal (e.g., CC pin) provided by USB port 2, in accordance with the specifications of the USB standard.

[0066] If, in step S503, it is determined that no external device 10 is connected to USB port 2 (step S503: NO), the display device 100 terminates the series of processes shown in Figure 5.

[0067] On the other hand, if it is determined in step S503 that an external device 10 is connected to USB port 2 (step S503: YES), the negotiation unit 112 negotiates with the external device 10 connected to USB port 2 in accordance with the specifications of the USB-PD standard to determine whether the external device 10 connected to USB port 2 is capable of outputting 5V power (i.e., the voltage required by the external device 10 connected to USB port 1) (step S504).

[0068] In this case, the negotiation unit 112 does not negotiate with the external device 10 connected to the USB port 1, but instead uses a predetermined power level (5V) that is stored in memory or the like, which is sufficient to drive the external device 10 connected to the USB port 1.

[0069] In step S504, if it is determined that the external device 10 connected to USB port 2 is not capable of outputting 5V power (step S504: NO), the display device 100 terminates the series of processes shown in Figure 5.

[0070] On the other hand, in step S504, if it is determined that the external device 10 connected to the USB port 2 is capable of outputting 5V power (step S504: YES), the pass-through control unit 114 determines whether or not it is necessary to reduce the power consumption of the display device 100 (step S505).

[0071] In step S505, the pass-through control unit 114 determines that it is necessary to reduce the power consumption of the display device 100 if the following equation (1) is true.

[0072] Power supplied from the external device 10 connected to the USB port 2 - Power consumption of the display device 100 < Power required by the external device 10 connected to the USB port 1...(1)

[0073] That is, the pass - through control unit 114 reduces the power consumption of the display device 100 on the condition that the power value obtained by subtracting the power consumption of the display device 100 from the power value supplied from the external device 10 connected to the USB port 2 is smaller than the power value required by the external device 10 connected to the USB port 1.

[0074] In step S505, when it is determined that it is necessary to reduce the power consumption of the display device 100 (step S505: YES), the pass - through control unit 114 reduces the power consumption of the display device 100 by switching the display device 100 to the power - consumption reduction mode (step S506). Thereafter, the display device 100 proceeds to step S507 for processing.

[0075] [[ID=…]] On the other hand, in step S505, when it is determined that it is not necessary to reduce the power consumption of the display device 100 (step S505: NO), the display device 100 proceeds to step S507 for processing.

[0076] In step S507, the negotiation unit 112 negotiates with the external device 10 connected to the USB port 2 to change the output of the external device 10 connected to the USB port 2 to 5V (step S507).<000027…

[0077] Specifically, the negotiation unit 112 notifies the sink (an external device 10 connected to USB port 1) of several voltage values ​​that the source (an external device 10 connected to USB port 2) can output. The negotiation unit 112 then receives notification from the sink of the voltage value that the sink requires (in this case, 5V) from among the multiple voltage values. Furthermore, the negotiation unit 112 notifies the source to output the voltage value that the sink requires (in this case, 5V). As a result, the source begins supplying power with the voltage value that the sink requires.

[0078] Then, the pass-through control unit 114 switches the power pass-through from USB port 2 to USB port 1 to ON (step S508).

[0079] As a result, a portion of the 5V power input from USB port 2 is output from USB port 1 as power required by the external device 10 connected to USB port 1, and the power to the external device 10 connected to USB port 1 is switched ON (step S509).

[0080] For example, if the external device 10 connected to USB port 1 is a video signal conversion cable 20, the video signal conversion cable 20 can start converting the video signal supplied from a terminal such as a smartphone, and transmitting the converted video signal to the display device 100, when its power is switched ON.

[0081] Subsequently, the display device 100 completes the series of processes shown in Figure 5.

[0082] (Example of message and brightness setting screen display by display device 100) Figures 6 and 9 show examples of message display by the display device 100 according to one embodiment. Figures 7 and 8 show examples of brightness setting screen display by the display device 100 according to one embodiment.

[0083] As already explained, in one embodiment of the display device 100, if the power that can be output from the second USB port 105A is insufficient to meet the power requirements of the second external device 10, the display device 100 can be switched from normal mode to low brightness mode. As a result, in one embodiment of the display device 100, the power consumption of the display device 100 can be reduced, and the power required by the second external device 10 can be output from the second USB port 105A.

[0084] In this case, as shown in Figure 6, the display control unit 115 can display a message 601 on the display panel 102 to notify the user that the display device 100 is switching to low brightness mode.

[0085] Furthermore, as shown in Figures 7 and 8, the display control unit 115 can display a brightness setting screen 701 on the display panel 102, which displays the brightness setting value of the display panel 102 as a bar graph, based on the user's operation of the UI 104.

[0086] Figure 7 shows the brightness setting screen 701 when the display device 100 is in normal mode. Figure 8 shows the brightness setting screen 701 when the display device 100 is in low brightness mode. The brightness setting screen 701 shown in Figure 8 indicates that the upper limit of the brightness of the display panel 102 has been reduced.

[0087] Furthermore, as shown in Figure 8, if the upper limit of the brightness of the display panel 102 has been reduced, and the user attempts to increase the brightness of the display panel 102 above the upper limit, the pass-through control unit 114 will disable the operation.

[0088] As another example, in one embodiment, the display device 100 can turn off its wireless communication function (e.g., communication I / F 103) if the power that can be output from the second USB port 105A is insufficient for the power required by the second external device 10. This allows the display device 100 to reduce its own power consumption and output the power required by the second external device 10 from the second USB port 105A.

[0089] In this case, as shown in Figure 9, the display control unit 115 can display a message 602 on the display panel 102 to notify the user that the wireless communication function of the display device 100 is being turned off.

[0090] (Relationship between brightness setting of display panel 102 and power consumption) Figure 10 is a graph showing the relationship between the brightness setting and power consumption of the display panel 102 of the display device 100 according to one embodiment.

[0091] In the graph shown in Figure 10, the vertical axis represents the power consumption [W] of the display panel 102, and the horizontal axis represents the brightness setting value of the display panel 102.

[0092] As shown in Figure 10, the display panel 102 allows the brightness setting value to be set within the range of "0" to "100".

[0093] Furthermore, the power consumption of the display panel 102 increases in proportion to the brightness setting value. Therefore, in one embodiment of the display device 100, the power consumption of the display device 100 can be reduced by reducing the upper limit of the brightness setting value of the display panel 102.

[0094] For example, in the example shown in Figure 10, the power consumption of the display panel 102 can be calculated using the following formula (2).

[0095] Power consumption [W] = 1 / 2 × brightness setting value + 5 ... (2)

[0096] (An example of the processing procedure by the display device 100 (second example)) Figure 11 is a flowchart showing an example (second example) of the processing procedure by the display device 100 according to one embodiment.

[0097] The flowchart shown in Figure 11 differs from the flowchart shown in Figure 5 in that step S521 is provided between step S504 and step S505.

[0098] In step S521, the pass-through control unit 114 determines whether the remaining battery level of the battery 108 in the display device 100 is below a predetermined threshold (step S521). The predetermined threshold is a value that is at least sufficient to power the display device 100 with battery power.

[0099] If, in step S521, it is determined that the battery level is below a predetermined threshold (step S521: YES), the display device 100 proceeds to step S505.

[0100] On the other hand, if it is determined in step S521 that the battery level is not below a predetermined threshold (step S521: NO), the display device 100 proceeds to step S507.

[0101] According to the flowchart in Figure 11, if the battery level of the battery 108 is sufficient to power the display device 100 on battery power (above a predetermined threshold), even if the power that can be output from USB port 1 is insufficient for the power required by the external device 10 connected to USB port 1, powering the display device 100 on battery power allows the power input from USB port 2 to be output from USB port 1 without being consumed by the display device 100. Therefore, the power required by the external device 10 connected to USB port 1 can be output from USB port 1. Accordingly, according to the flowchart in Figure 11, the frequency of reducing the power consumption of the display device 100 can be suppressed, and thus, a decrease in usability can be suppressed.

[0102] Furthermore, if the battery level of the battery 108 falls below a predetermined threshold while the display device 100 is running on battery power, the display device 100 may terminate battery operation and switch to a power consumption reduction mode to reduce the power consumption of the display device 100. This allows the display device 100 to continuously supply power to the external device 10 connected to the USB port 1.

[0103] (An example of the processing procedure by the display device 100 (third example)) Figure 12 is a flowchart showing an example (third example) of the processing procedure by the display device 100 according to one embodiment.

[0104] The flowchart shown in Figure 12 differs from the flowchart shown in Figure 5 in that steps S531 to S535 are provided following step S509.

[0105] In step S531, the pass-through control unit 114 determines whether or not the external device 10 connected to the USB port 1 has a video output function (step S531).

[0106] In step S531, if it is determined that the external device 10 connected to USB port 1 has a video output function (step S531: YES), the display device 100 terminates the series of processes shown in Figure 5.

[0107] On the other hand, if in step S531 it is determined that the external device 10 connected to USB port 1 does not have a video output function (step S531: NO), the pass-through control unit 114 determines whether the display device 100 is in power consumption reduction mode (step S532).

[0108] If, in step S532, it is determined that the display device 100 is not in power consumption reduction mode (step S532: NO), the display device 100 terminates the series of processes shown in Figure 5.

[0109] On the other hand, if it is determined in step S532 that the display device 100 is in power consumption reduction mode (step S532: YES), the pass-through control unit 114 switches the power pass-through from USB port 2 to USB port 1 to OFF (step S533).

[0110] Then, the negotiation unit 112 negotiates with the external device 10 connected to the USB port 2, thereby changing the output voltage of the external device 10 connected to the USB port 2 back to the voltage before it was changed to 5V (step S534).

[0111] Furthermore, the pass-through control unit 114 switches the display device 100 from power consumption reduction mode to normal mode (step S535). After that, the display device 100 completes the series of processes shown in Figure 5.

[0112] According to the flowchart in Figure 12, if the external device 10 connected to USB port 1 does not have a video output function, the display device 100 will not switch to power consumption reduction mode and will not output power from USB port 1, even if the power that can be output from USB port 1 is insufficient for the power required by the external device 10 connected to USB port 1. Therefore, according to the flowchart in Figure 12, the frequency of power consumption reduction of the display device 100 can be suppressed, and thus, a decrease in usability can be suppressed.

[0113] Furthermore, the above embodiment makes it possible to display the screen on the display device 100 using a terminal and a video signal conversion cable in a variety of environments. For example, there are situations where the user with the display device 100 needs to be used in a constantly changing environment, such as when moving locations, changing the terminal (laptop, smartphone, tablet, etc.) on which the screen should be displayed, or changing the video signal conversion cable or AC adapter used for connection. In such cases, the display device 100 can be provided that can display the screen of a terminal device in a wider range of situations.

[0114] Although preferred embodiments of the present invention have been described in detail above, the present invention is not limited to these embodiments, and various modifications or changes are possible within the scope of the gist of the present invention as described in the claims.

[0115] For example, the "connection method" is not limited to a USB port, as long as it allows for power pass-through.

[0116] Furthermore, methods for "reducing the power consumption of a display device" are not limited to methods such as lowering the upper limit of the brightness of the display panel or turning off the wireless communication function of the display device, as long as it is possible to reduce the power consumption of the display device. [Explanation of Symbols]

[0117] 10 External equipment 11. AC adapter (the first external device that supplies power) 12 Smartphones 20. Video signal conversion cable (second external device receiving power) 21 HDMI I / F 22 Signal conversion section 23 USB I / F 24 Power supply section 100 display device 101 Control Unit 102 Display Panel 103 Communication I / F 104 UI 105 USB I / F 105A USB port (connection method) 105A1 First USB port 105A2 Second USB port 107 Power supply section 108 batteries 111 Connection detection unit 112 Negotiation Department 113 Power output section 114 Pass-through control unit 115 Display Control Unit 601,602 Messages 701 Brightness setting screen [Prior art documents] [Patent Documents]

[0118] [Patent Document 1] Japanese Patent Publication No. 2020-124035

Claims

1. Multiple connection methods, A connection detection unit that detects when an external device is connected to the connection means, A negotiation unit that performs power-related negotiations with the external device connected to the connection means, Based on the negotiation results by the negotiation unit, a power output unit outputs the power required by the external device connected to the connection means from the connection means to which the external device is connected, A pass-through control unit that outputs power input from the first connection means to which the first external device is connected, to the second connection means to which the second external device is connected. A display device equipped with, The pass-through control unit, If the power that can be output from the second connection means is insufficient to meet the power requirements of the second external device, the power consumption of the display device is reduced so that the power required by the second external device can be output from the second connection means. The device includes a battery that supplies power for driving the display device, The pass-through control unit, When the battery level of the battery is above a predetermined threshold, the display device is powered by the battery, and the power input from the first connection means is output from the second connection means without reducing the power consumption of the display device. A display device characterized by the following features.

2. Multiple connection means, A connection detection unit that detects when an external device is connected to the connection means, A negotiation unit that performs power-related negotiations with the external device connected to the connection means, Based on the negotiation results by the negotiation unit, a power output unit outputs the power required by the external device connected to the connection means from the connection means to which the external device is connected, A pass-through control unit that outputs power input from the first connection means to which the first external device is connected, to the second connection means to which the second external device is connected. A display device equipped with, The pass-through control unit, If the power that can be output from the second connection means is insufficient to meet the power requirements of the second external device, the power consumption of the display device is reduced so that the power required by the second external device can be output from the second connection means. The pass-through control unit, If the second external device does not have a video output function, even if the power that can be output from the second connection means is insufficient to meet the power requirements of the second external device, the power consumption of the display device will not be reduced, and power will not be output from the second connection means. A display device characterized by the following features.

3. The pass-through control unit, By lowering the upper limit of the brightness of the display panel of the display device, the power consumption of the display device is reduced, and the power required by the second external device is controlled to be output from the second connection means. The display device according to feature 1 or 2.

4. The pass-through control unit, The amount by which the upper limit of the brightness of the display panel is reduced is determined according to the amount of power shortage required by the second external device. The display device according to feature 3.

5. The pass-through control unit, When the upper limit of the brightness of the display panel is reduced, operations that attempt to increase the brightness of the display panel above the upper limit are disabled. The display device according to feature 3.

6. The pass-through control unit, By turning off the wireless communication function of the display device, the power required by the second external device is controlled to be output from the second connection means. The display device according to feature 1 or 2.

7. The negotiation unit is, When the second external device is connected to the second connection means, if the first external device is already connected to the first connection means, negotiation with the first external device is performed at the moment the second external device is connected to the second connection means, causing the first external device to output power at the voltage value required by the second external device. The display device according to feature 1 or 2.

8. When the second external device is connected to the second connection means, and it is determined that the second external device is an external device to which power is supplied, The negotiation unit does not negotiate with the second external device. The pass-through control unit causes the second connection means to output a predetermined power capable of driving the second external device. The display device according to feature 1 or 2.

9. The aforementioned connecting means is The external device connected to the connection means is capable of power input / output and data transmission / reception. The display device according to feature 1 or 2.

10. The aforementioned connecting means is USB port The display device according to feature 1 or 2.

11. Display panel and A display control unit that causes the display panel to display a message to notify the user that the power consumption of the display device will be reduced, and The display device according to claim 1 or 2, characterized by comprising:

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