PICTURE DISPLAY DEVICE

Abstract

An image display device according to an embodiment of the present disclosure comprises: a display; a signal processing device; and a power supply for supplying a display driver voltage to the display, wherein the power supply comprises a converter containing switching elements and converting a level of an input DC voltage and outputting the display driver voltage, wherein the converter is configured to operate in response to a load at an output terminal of the converter in a first mode in which the switching elements perform a continuous switching operation at a first frequency, and in a second mode in which the switching elements perform the continuous switching operation and then stop the switching operation for a predetermined period of time or perform the switching operation at a second frequency which is lower than the first frequency.Accordingly, it is possible to reduce the increase in output voltage at low load or idle.

Description

BACKGROUND 1. Technical field

[0001] The present disclosure relates to an image display device, and more particularly to an image display device capable of reducing the rise in output voltage at a low load or idle state. 2. Description of the state of the art

[0002] An image display device is a device that displays images.

[0003] Recently, with the increase in image resolution and image sharpness, the display resolution and peak luminance of a display in an image display device also increase.

[0004] The higher the screen resolution or peak luminance of a display, the higher the power consumption of the display.

[0005] However, if the load on the display decreases or the display is idle, the voltage supplied to the display increases. SUMMARY

[0006] The object of the present disclosure is to provide an image display device capable of reducing the increase in output voltage at low load or idle.

[0007] Another object of the present disclosure is to provide an image display device capable of stably supplying a display driving voltage.

[0008] Another object of the present disclosure is to provide an image display device capable of reducing the power consumption of a power supply.

[0009] To achieve the above and other objects, an image display device according to an embodiment of the present disclosure includes: a display; a signal processing device configured to output an image signal to the display;and a power supply configured to supply a display drive voltage to the display, the power supply comprising a converter including switching elements and configured to convert a level of an input DC voltage based on a switching operation of the switching elements and output the display drive voltage, the converter configured to operate in response to a load at an output terminal of the converter in a first mode in which the switching elements perform a continuous switching operation at a first frequency, and in a second mode in which the switching elements perform the continuous switching operation and then stop the switching operation for a predetermined period of time or perform the switching operation at a second frequency lower than the first frequency;

[0010] Furthermore, the converter may be configured to operate in the second operating mode in response to the load at the output terminal of the converter being less than or equal to a reference value, in which the switching elements perform the continuous switching operation and then stop the switching operation for the predetermined period of time or perform the switching operation at the second frequency.

[0011] Furthermore, the converter may be arranged to operate in the second operating mode in response to a black image displayed on the display, in which the switching elements perform the continuous switching operation and then stop the switching operation for the predetermined period of time or perform the switching operation at the second frequency.

[0012] Furthermore, the converter may comprise: a transformer; a first switching element and a second switching element arranged at an input terminal of the transformer and connected in series with each other; and a resonant capacitor and a resonant inductor arranged between the input terminal of the transformer and the second switching element and connected thereto.

[0013] Furthermore, the converter may further comprise: full-bridge diodes arranged at an output terminal of the transformer; and a capacitor element arranged at an output terminal of the full-bridge diodes.

[0014] Furthermore, it is desirable that the resistance element is not arranged at both ends of the capacitor element.

[0015] Furthermore, the second frequency may correspond to a frequency outside the audible frequency range.

[0016] Furthermore, the converter may further comprise a voltage detection circuit configured to detect a voltage across the second switching element.

[0017] Furthermore, the converter may be configured to switch on the second switching element when the voltage across the second switching element detected by the voltage detection circuit is zero.

[0018] Furthermore, the converter may be configured to turn on the second switching element during operation in the second mode in response to the voltage across the second switching element detected by the voltage detection circuit being a zero voltage.

[0019] Furthermore, the voltage detection circuit may include: a capacitor connected to a first node between the first switching element and the second switching element; a Zener diode arranged between the capacitor and a ground terminal; and a resistance element having one end connected to a second node between the capacitor and the Zener diode.

[0020] Furthermore, the converter may further include a switching controller configured to control the first switching element and the second switching element, wherein the switching controller is configured to control a zero-voltage switching of the second switching element based on a voltage at the second node.

[0021] Furthermore, the power supply may further comprise a second converter configured to convert an input AC voltage into a DC voltage, wherein the converter is configured to convert the DC voltage from the second converter and output the display drive voltage to the display.

[0022] Furthermore, the signal processing device may be configured to: in response to a selection of a mode for turning on the power supply of the display in a setting screen, control the power supply so that a display drive voltage having a first level is supplied to the display; and in response to a selection of a mode for turning off the power supply of the display in the setting screen, control the power supply so that a display drive voltage having a second level is supplied to the display.

[0023] Furthermore, the signal processing device may be configured to: in response to a selection of a mode for turning on the power supply of the display in a setting screen, control the power supply so that the display drive voltage at the first level is supplied to the display based on the second operating mode; and in response to a selection of a mode for turning off the power supply of the display in the setting screen, control the power supply so that the display drive voltage at the second level is supplied to the display based on the first operating mode.

[0024] An image display device according to another embodiment of the present disclosure includes: a display; a signal processing device configured to output an image signal to the display;and a power supply configured to supply a display drive voltage to the display, the power supply including a converter including switching elements configured to convert a level of an input DC voltage based on a switching operation of the switching elements and output the display drive voltage, the converter configured to operate in response to a load at an output terminal of the converter in a first mode of operation in which the switching elements perform a continuous switching operation with a first duty cycle, and in a second mode of operation in which the switching elements perform the switching operation with a second duty cycle that is less than the first duty cycle.

[0025] Furthermore, the converter may be configured to operate in the second operating mode in response to the load at the output terminal of the converter being less than or equal to a reference value, in which the switching elements perform the switching operation with the second duty cycle.

[0026] Furthermore, the converter may be configured to operate in the second operating mode in response to a black image on the display, in which the switching elements perform the switching operation with the second duty cycle.

[0027] Furthermore, the converter may comprise: a transformer; a first switching element and a second switching element arranged at an input terminal of the transformer and connected in series with each other; and a resonant capacitor and a resonant inductor arranged between the input terminal of the transformer and the second switching element and connected thereto. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other objects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: Fig. 1 is a diagram showing an image display device according to an embodiment of the present disclosure; Fig. 2 is an example of an internal block diagram of the image display device; Fig. 3 an example of an internal block diagram of a signal processing device of Fig. 2 is; Fig. 4A is a diagram showing a method for controlling a remote control device of Fig. 2 shows, is; Fig. 4B an internal block diagram of the remote control of Fig. 2 is; Fig. 5 an exemplary internal block diagram of a display of Fig. 2 is; Fig. 6A and Fig. 6B are diagrams referred to in the description of an organic light-emitting panel of Fig. 5 is referred to; Fig. 7 is an exemplary internal block diagram of an image display device according to an embodiment of the present disclosure; Fig. 8 is an exemplary circuit diagram of a power supply related to the present disclosure; Fig. 9 is an exemplary circuit diagram of a power supply according to an embodiment of the present disclosure; Fig. 10A to 13C are diagrams referred to in the description of Fig. 9 is referred to; and Fig. 14A to 14D are flowcharts illustrating an operating method of an image display device according to various embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Hereinafter, the present disclosure will be described in detail with reference to the accompanying drawings.

[0030] The suffixes "module" and "unit" used in the following description are intended solely to simplify the preparation of the specification and do not have different meanings. Accordingly, the suffixes "module" and "unit" can be used interchangeably.

[0031] Fig. 1 is a diagram showing an image display device according to an embodiment of the present disclosure.

[0032] As shown in the figure, an image display device 100 may include a display 180.

[0033] The display resolution of the 180-degree display continues to increase, from 2K to 4K to 8K to 16K and beyond, and the peak luminance of the 180-degree display also increases. Accordingly, the power consumption of the 180-degree display also increases.

[0034] Furthermore, the display 180 can be implemented using one of various panels. For example, the display 180 can be a liquid crystal display (LCD), an organic light-emitting diode (OLED), or an inorganic light-emitting diode (LED).

[0035] The liquid crystal display may require a backlight in addition to a field for displaying the image.

[0036] On the other hand, the organic light-emitting display or the inorganic light-emitting display does not require a backlight for image display.

[0037] The image display device 100 according to an embodiment of the present disclosure provides a method for reducing the increase in the output voltage at low load or idle, for example, in the case where an image displayed on the display 180 is a black image.

[0038] For this purpose, the image display device according to an embodiment of the present disclosure comprises a display 180, a signal processing device 170 (see Fig. 2) which is arranged to output an image signal to the display 180, and a power supply 190 (see Fig. 2) which is configured to supply a display driver voltage to the display 180.

[0039] Furthermore, according to an embodiment of the present disclosure, the power supply 190 includes a converter 910 (see Fig. 7) which includes switching elements and is configured to convert a level of an input DC voltage based on a switching operation of the switching elements to output a display drive voltage.

[0040] Furthermore, the converter 910 (see Fig. 8) According to an embodiment of the present disclosure, in a first mode or a second mode in response to a load at an output terminal of the converter, wherein in the first mode, the switching elements perform a continuous switching operation at a first frequency, and in the second mode, the switching elements perform the continuous switching operation and then stop the switching operation for a predetermined period of time or perform the switching operation at a second frequency lower than the first frequency. Accordingly, it is possible to reduce the rise in the output voltage at a light load or idle state. In addition, the display drive voltage can be stably supplied. Furthermore, the power consumption of the power supply 190 can be reduced.

[0041] Furthermore, the converter 910 (see Fig. 8) According to another embodiment of the present disclosure, in a first operating mode or a second operating mode in response to a load at an output terminal of the converter, wherein the switching elements in the first operating mode perform a continuous switching operation with a first switching duration, and the switching elements in a second operating mode perform the switching operation with a second switching duration that is shorter than the first switching duration. This makes it possible to reduce the rise in the output voltage under light load or idle conditions. In addition, the display drive voltage can be supplied stably. Furthermore, the power consumption of the power supply 190 can be reduced.

[0042] The image display device 100 of Fig. 1 may be a television, a monitor, a vehicle display device, a tablet PC, a mobile terminal, and the like.

[0043] Fig. 2 is an example of an internal block diagram of the image display device of Fig. 1.

[0044] Referring to Fig. 2, the image display device 100 according to an embodiment of the present disclosure includes an image receiver 105, an external device interface 130, a memory 140, a user input interface 150, a sensor device (not shown), a signal processing device 170, a display 180, and an audio output device 185.

[0045] The image receiver 105 may include a tuner 110, a demodulator 120, a network interface 135, and an external device interface 130.

[0046] Contrary to the illustration, the image receiver 105 may also contain only the tuner 110, the demodulator 120, and the external device interface 130. That is, the network interface 135 may not be included.

[0047] Tuner 110 selects an RF broadcast signal corresponding to a user-selected channel or all previously stored channels from among the radio-frequency broadcast signals received via an antenna (not shown). Furthermore, the selected RF broadcast signal is converted into an intermediate frequency signal, a baseband image, or an audio signal.

[0048] For example, if the selected RF broadcast signal is a digital broadcast signal, tuner 110 converts the digital broadcast signal into a digital IF (DIF) signal. If the selected RF broadcast signal is an analog broadcast signal, tuner 110 converts the analog broadcast signal into an analog baseband video or voice signal (CVBS / SIF). That is, tuner 110 can process a digital broadcast signal or an analog broadcast signal. The analog baseband video or voice signal (CVBS / SIF) output by tuner 110 can be directly input to signal processing device 170.

[0049] Meanwhile, tuner 110 may include a plurality of tuners for receiving broadcast signals from a plurality of channels. Alternatively, a single tuner may be used to simultaneously receive broadcast signals from multiple channels.

[0050] The demodulator 120 receives the converted digital IF signal DIF from the tuner 110 and performs a demodulation process.

[0051] The demodulator 120 can perform demodulation and channel decoding and then output a stream signal TS. At this time, the stream signal can be a multiplexed signal of an image signal, an audio signal, or a data signal.

[0052] The stream signal output from demodulator 120 may be input to signal processing device 170. Signal processing device 170 performs demultiplexing, image / audio signal processing, and the like, and then outputs an image to display 180 and audio to audio output device 185.

[0053] The external device interface 130 can transmit or receive data with a connected external device (not shown), such as a set-top box 50. For this purpose, the external device interface 130 can include an A / V input and output device (not shown).

[0054] The external device interface 130 can be connected wired or wirelessly to an external device such as a digital versatile disk (DVD), a Blu-ray, a game device, a camera, a camcorder, a computer (notebook), and a set-top box, and can perform an input / output operation with an external device.

[0055] The A / V input and output device can receive video and audio signals from an external device. Meanwhile, a wireless transceiver (not shown) can perform short-range wireless communication with other electronic devices.

[0056] The external device interface 130 can exchange data with a neighboring mobile terminal 600 via the wireless transceiver (not shown). Specifically, the external device interface 130 can receive device information, executed application information, application images, and the like from the mobile terminal 600 in a mirroring mode.

[0057] The network interface 135 provides an interface for connecting the image display device 100 to a wired / wireless network, including the Internet. For example, the network interface 135 can receive content or data provided by the Internet, a content provider, or a network operator via the network.

[0058] Furthermore, the network interface 135 may include a wireless transceiver (not shown).

[0059] The memory 140 can store a program for each signal processing and control in the signal processing device 170 and can store a signal-processed image, audio, or data signal.

[0060] Furthermore, the memory 140 may serve to temporarily store image, audio, or data signals input to the interface of the external device 130. Furthermore, the memory 140 may store information about a specific broadcast channel through a channel memory function, such as a channel map.

[0061] Although Fig. Although Figure 2 shows that the memory is provided separately from the signal processing device 170, the scope of the present disclosure is not limited thereto. The memory 140 may be included in the signal processing device 170.

[0062] The user input interface 150 transmits a signal input by the user to the signal processing device 170 or transmits a signal from the signal processing device 170 to the user.

[0063] For example, it may send / receive a user input signal such as power on / off, channel selection, screen adjustment, etc., from a remote control 200, may transmit a user input signal from a local button (not shown) such as a power button, a channel button, a volume button, a set value, etc., to the signal processing device 170, may transmit a user input signal input from a sensor device (not shown) that detects a user's gesture to the signal processing device 170, or may transmit a signal from the signal processing device 170 to the sensor device (not shown).

[0064] The signal processing device 170 may demultiplex the input stream via the tuner 110, the demodulator 120, the network interface 135, or the external device interface 130, or process the demultiplexed signals to generate and output a signal for video or audio output.

[0065] For example, the signal processing device 170 receives a broadcast signal or an HDMI signal received from the image receiver 105 and performs signal processing based on the received broadcast signal or the HDMI signal to thereby output a processed image signal.

[0066] The image signal processed by the signal processing device 170 is input to the display 180 and can be displayed as an image corresponding to the image signal. Furthermore, the image signal processed by the signal processing device 170 can be input to the external output device via the external device interface 130.

[0067] The audio signal processed by the signal processing device 170 can be output as an audio signal to the audio output device 185. Furthermore, the audio signal processed by the signal processing device 170 can be input to the external output device via the external device interface 130.

[0068] Although in Fig. 2, the signal processing device 170 may include a demultiplexer, an image processor, and the like. That is, the signal processing device 170 may perform a variety of signal processing operations and may therefore be implemented in the form of a system on chip (SOC). This will be explained later with reference to Fig. 3 described.

[0069] Furthermore, the signal processing device 170 can control the overall operation of the image display device 100. For example, the signal processing device 170 can control the tuner 110 to control the tuning of the RF transmission according to the channel selected by the user or the previously stored channel.

[0070] Furthermore, the signal processing device 170 can control the image display device 100 according to a user command input via the user input interface 150 or an internal program.

[0071] Furthermore, the signal processing device 170 can control the display 180 to display an image. At this time, the image displayed on the display 180 can be a still image or a moving image, and a 2D image or a 3D image.

[0072] Furthermore, the signal processing device 170 can represent a specific object in an image displayed on the display 180. The object can be, for example, a connected web screen (newspaper, magazine, etc.), an electronic program guide (EPG), various menus, a widget, an icon, a still image, a moving image, or text.

[0073] Furthermore, the signal processing device 170 can detect the user's position based on the image captured by a photographic device (not shown). For example, the distance (z-axis coordinate) between a user and the image display device 100 can be determined. Furthermore, the x-axis coordinate and y-axis coordinate in the display 180 corresponding to a user's position can be determined.

[0074] The display 180 generates a drive signal (or drive signal) by converting an image signal, a data signal, an OSD signal, a control signal processed by the signal processing device 170, an image signal, a data signal, a control signal, etc., received from the interface of the external device 130.

[0075] The display 180 can be configured as a touchscreen and used as both an input and output device.

[0076] The audio output device 185 receives a signal processed by the signal processing device 170 and outputs it as sound.

[0077] The photographic device (not shown) photographs a user. The photographic device (not shown) may be implemented by a single camera, but the present disclosure is not limited thereto and may be implemented by a plurality of cameras. The image information captured by the photographic device (not shown) may be input to the signal processing device 170.

[0078] The signal processing device 170 can recognize a gesture of the user based on any of the images captured by the photographic device (not shown), the signals detected by the sensor device (not shown), or a combination thereof.

[0079] The power supply 190 supplies the image display device 100 with the appropriate power. Specifically, the power can be supplied to a signal processing device 170, which may be implemented as a system-on-chip (SOC), a display 180 for displaying an image, and an audio output device 185 for outputting sound.

[0080] In particular, the power supply 190 may include a converter for converting alternating current to direct current and a DC / DC converter for converting the DC voltage level.

[0081] The remote control 200 transmits the user inputs to the user input interface 150. For this purpose, the remote control 200 may use Bluetooth, radio frequency (RF) communication, infrared (IR) communication, ultra-wideband (UWB) communication, ZigBee, or the like. Furthermore, the remote control 200 may receive the image, audio, or data signal output from the user input interface 150 and display it on the remote control 200 or output it as an audio signal.

[0082] The image display device 100 may be a stationary or mobile digital broadcast receiver capable of receiving digital broadcasts.

[0083] The Fig. The block diagram of the image display device 100 shown in Figure 2 is a block diagram for one embodiment of the present disclosure. Each component of the block diagram can be integrated, added, or omitted according to a specification of the actually implemented image display device 100. That is, two or more components can be combined into a single component as needed, or a single component can be split into two or more components. The function performed in each block is described to illustrate embodiments of the present disclosure, and specific operations and devices do not limit the scope of the present disclosure.

[0084] Fig. 3 is an example of an internal block diagram of the signal processing device in Fig. 2.

[0085] As shown in the figure, the signal processing device 170 according to an embodiment of the present disclosure may include a demultiplexer 310, an image processor 320, a processor 330, and an audio processor 370. Furthermore, the signal processing device 170 may also include a data processor (not shown).

[0086] Demultiplexer 310 demultiplexes the input stream. For example, if an MPEG-2 TS is input, it can be demultiplexed into an image, an audio, and a data signal. In this case, the stream signal input to demultiplexer 310 can be a stream signal output from tuner 110, demodulator 120, or external device interface 130.

[0087] The image processor 320 can perform signal processing on an input image. For example, the image processor 320 can perform image processing on an image signal demultiplexed by the demultiplexer 310.

[0088] For this purpose, the image processor 320 may include an image decoder 325, a scaler 335, an image quality processor 335, an image encoder (not shown), an OSD processor 340, a frame rate converter 350, a formatter 360, etc.

[0089] The image decoder 325 decodes a demultiplexed image signal, and the scaler 335 performs scaling so that the resolution of the decoded image signal can be output on the display 180.

[0090] The image decoder 325 may include a decoder for various standards. For example, a 3D image decoder for MPEG-2, an H.264 decoder, a color image and a depth image decoder, and a multi-view image decoder may be provided.

[0091] The scaler 335 may scale an input image signal decoded by the image decoder 325, or the like.

[0092] For example, when the size or resolution of an input image signal is small, the scaler 335 may upscale the input image signal, and when the size or resolution of the input image signal is large, the scaler 335 may downscale the input image signal.

[0093] The image quality processor 635 may subject an input image signal decoded by the image decoder 325 to image quality processing or the like.

[0094] For example, the image quality processor 635 may perform noise reduction for an input image signal, expand the high gray level resolution of the input image signal, improve the image resolution, perform high dynamic range (HDR) signal processing, change the frame rate, perform image quality processing suitable for the characteristics of a panel, particularly an OLED panel, etc.

[0095] The OSD processor 340 generates an OSD signal in response to user input or on its own. For example, the OSD processor 340 may generate a signal for displaying various information as graphics or text on the screen of the display 180 based on a user input signal. The generated OSD signal may include various data, such as a user interface screen of the image display device 100, various menu screens, a widget, and an icon. Furthermore, the generated OSD signal may include a 2D object or a 3D object.

[0096] Furthermore, OSD processor 340 may generate a pointer that may be displayed on the display based on a pointer signal input from remote control 200. In particular, such a pointer may be generated by a pointer signal processing device, and OSD processor 340 may include such a pointer signal processing device (not shown). Of course, the pointer signal processing device (not shown) may be provided separately from OSD processor 340.

[0097] The frame rate converter (FRC) 350 can convert the frame rate of an input image. At the same time, the frame rate converter 350 can output the input image without converting the frame rate.

[0098] Meanwhile, the formatter 360 may change a format of an input image signal into a format suitable for displaying the image signal on a display, and output the image signal in the changed format.

[0099] In particular, the formatter 360 can change the format of an image signal to correspond to a display field.

[0100] In addition, the 360 ​​formatter can convert the format of an image signal. For example, the 360 ​​formatter can convert the format of a 3D image signal into one of various 3D formats, including a side-by-side format, a top-down format, a frame-sequential format, an interlaced format, a checker-box format, etc.

[0101] The processor 330 can control the overall operation of the image display device 100 or the signal processing device 170.

[0102] For example, processor 330 may control tuner 110 to control the tuning of an RF broadcast corresponding to a channel selected by a user or a previously stored channel.

[0103] Furthermore, the processor 330 can control the image display device 100 according to a user command input via the user input interface 150 or an internal program.

[0104] In addition, the processor 330 can transmit data to the network interface 135 or to the external device interface 130.

[0105] In addition, the processor 330 can control the demultiplexer 310, the image processor 320, and the like in the signal processing device 170.

[0106] Furthermore, the audio processor 370 in the signal processing device 170 can perform the audio processing of the demultiplexed audio signal. For this purpose, the audio processor 370 can contain various decoders.

[0107] In addition, the audio processor 370 in the signal processing device 170 can process a fundamental tone, a treble tone, a volume control, and the like.

[0108] The data processor (not shown) in signal processing device 170 can perform data processing on the demultiplexed data signal. For example, if the demultiplexed data signal is an encoded data signal, it can be decoded. The encoded data signal can be electronic program guide information that includes broadcast information, such as a start time and an end time of a program broadcast on each channel.

[0109] The Fig. The block diagram of the signal processing device 170 shown in Figure 3 is a block diagram for one embodiment of the present disclosure. Each component of the block diagram can be integrated, added, or omitted according to a specification of the actually implemented signal processing device 170.

[0110] In particular, the frame rate converter 350 and the formatter 360 may be provided separately in addition to the image processor 320.

[0111] Fig. 4A is a diagram illustrating a control method for a remote control of Fig. 2.

[0112] As in Fig. 4A(a), a pointer 205 corresponding to the remote control 200 is displayed on the display 180.

[0113] The user can move the remote control 200 up and down, left and right ( Fig. 4A(b)) and back and forth ( Fig. 4A(c)). The pointer 205 displayed on the display 180 of the image display device corresponds to the movement of the remote control 200. Such a remote control 200 may be referred to as a room remote control or 3D pointing device because the pointer 205 is moved and displayed according to the movement in a 3D space, as shown in the figure.

[0114] Fig. 4A(b) illustrates that when the user moves the remote control 200 to the left, the pointer 205 displayed on the display 180 of the image display device also moves to the left.

[0115] Information about the movement of the remote control 200, detected by a sensor of the remote control 200, is transmitted to the image display device. The image display device can calculate the coordinate of the pointer 205 from the information about the movement of the remote control 200. The image display device can display the pointer 205 so that it corresponds to the calculated coordinate.

[0116] Fig. 4A(c) illustrates a case where the user moves the remote control 200 away from the display 180 while pressing a specific button on the remote control 200. In this way, a selection area within the display 180 corresponding to the pointer 205 can be zoomed in and enlarged. When the user moves the remote control 200 close to the display 180, the selection area corresponding to the pointer 205 on the display 180 can be reduced in size. When the remote control 200 moves away from the display 180, the selection area can be reduced in size, and when the remote control 200 approaches the display 180, the selection area can be enlarged.

[0117] When the specific button of the remote control 200 is pressed, it is possible to exclude the detection of vertical and lateral movements. That is, when the remote control 200 moves away from or near the display 180, the up, down, left, and right movements are not detected, but only the forward and backward movements. Only the pointer 205 is moved according to the up, down, left, and right movements of the remote control 200 in a state where the specific button of the remote control 200 is not pressed.

[0118] Furthermore, the movement speed or the movement direction of the pointer 205 may correspond to the movement speed or the movement direction of the remote control 200.

[0119] Fig. 4B is an internal block diagram of the remote control of Fig. 2.

[0120] The figure shows that the remote control 200 includes a wireless transceiver 425, a user input device 435, a sensor device 440, an output device 450, a power supply 460, a memory 470, and a controller 480.

[0121] The wireless transceiver 425 transmits / receives a signal to / from one of the image display devices according to the above-described embodiments of the present disclosure. Among the image display devices according to the embodiments of the present disclosure, an image display device 100 is described as an example.

[0122] In the present embodiment, the remote control 200 may include an RF module 421 for transmitting and receiving signals to and from the image display device 100 according to an RF communication standard. Furthermore, the remote control 200 may include an IR module 423 for transmitting and receiving signals to and from the image display device 100 according to an IR communication standard.

[0123] In the present embodiment, the remote control 200 sends a signal containing information about the movement of the remote control 200 to the image display device 100 via the RF module 421.

[0124] Furthermore, the remote control 200 can receive the signal transmitted from the image display device 100 via the RF module 421. Furthermore, the remote control 200 can send a command to the image display device 100 via the IR module 423, such as turning on / off, changing the channel, changing the volume, and the like, as needed.

[0125] The user input device 435 can be implemented by a keypad, a button, a touchpad, a touchscreen, or the like. The user can operate the user input device 435 to input a command related to the image display device 100 into the remote control 200. If the user input device 435 includes a hard button, the user can input a command related to the image display device 100 into the remote control 200 by pressing the hard button. If the user input device 435 includes a touch screen, the user can touch a soft button of the touch screen to input the command related to the image display device 100 to the remote control 200. Furthermore, the user input device 435 can include various types of input means, such as a scroll button, a jog button, etc.that can be operated by the user, and the present disclosure does not limit the scope of the present disclosure.

[0126] The sensor device 440 may include a gyro sensor 441 or an acceleration sensor 443. The gyro sensor 441 may detect information about the movement of the remote control 200.

[0127] For example, the gyro sensor 441 can capture information about the operation of the remote control 200 based on the x, y, and z axes. The acceleration sensor 443 can capture information about the movement speed of the remote control 200. A distance measurement sensor can also be included to measure the distance to the display 180.

[0128] The output device 450 can output an image or an audio signal corresponding to the operation of the user input device 435 or a signal transmitted from the image display device 100. The output device 450 allows the user to determine whether the user input device 435 is being operated or the image display device 100 is being controlled.

[0129] The output device 450 may include, for example, an LED module 451 that is turned on when the user input device 435 is operated or a signal is sent to / received from the image display device 100 via the wireless transceiver 425, a vibration module 453 for generating a vibration, an audio output module 455 for outputting a sound, or a display module 457 for outputting an image.

[0130] The power supply 460 supplies power to the remote control 200. If the remote control 200 is not moved for a certain period of time, the power supply 460 can interrupt the power supply to prevent energy waste. The power supply 460 can resume power supply when a specific button on the remote control 200 is pressed.

[0131] The memory 470 can store various types of programs, application data, and the like required for controlling or operating the remote control 200. When the remote control 200 wirelessly transmits and receives a signal to / from the image display device 100 via the RF module 421, the remote control 200 and the image display device 100 transmit and receive a signal over a specific frequency band. The controller 480 of the remote control 200 can store information regarding a frequency band or the like for wirelessly transmitting and receiving a signal to / from the image display device 100 paired with the remote control 200 in the memory 470 and refer to the stored information.

[0132] The control unit 480 controls various operations related to controlling the remote control 200. The control unit 480 may transmit a signal corresponding to a particular keystroke of the user input device 435 or a signal corresponding to the movement of the remote control 200 detected by the sensor device 440 to the image display device 100 via the wireless transceiver 425.

[0133] The user input interface 150 of the image display device 100 includes a wireless transceiver 151 that can wirelessly send and receive a signal to and from the remote control 200, and a coordinate value calculator 415 that can calculate the coordinate value of a pointer according to the operation of the remote control 200.

[0134] The user input interface 150 can wirelessly transmit and receive a signal to and from the remote control 200 via the RF module 412. Furthermore, the user input interface 150 can receive a signal transmitted from the remote control 200 via the IR module 413 according to an IR communication standard.

[0135] The coordinate value calculator 415 can correct a hand tremor or an error from a signal corresponding to the operation of the remote controller 200 received via the wireless transceiver 151, and calculate the coordinate value (x, y) of the pointer 205 to be displayed on the display 180.

[0136] The transmission signal of the remote control 200, which is input to the image display device 100 via the user input interface 150, is transmitted to the control unit 180 of the image display device 100. The control unit 180 can determine the information about the operation of the remote control 200 and the key operation from the signal transmitted by the remote control 200 and control the image display device 100 accordingly.

[0137] In another example, the remote control 200 may calculate the pointer coordinate value according to the operation and output it to the user input interface 150 of the image display device 100. In this case, the user input interface 150 of the image display device 100 may transmit information about the received pointer coordinate value to the control unit 180 without requiring a separate correction process for hand shaking or errors.

[0138] Another example: Contrary to the illustration, the coordinate value calculator 415 may be located in the signal processing device 170 and not in the user input interface 150.

[0139] Fig. 5 is an example internal block diagram of a display of Fig. 2.

[0140] Referring to Fig. 5, an organic light-emitting panel-based display 180b may include an organic light-emitting panel 210b, a first interface 230b, a second interface 231b, a timing controller 232b, a gate driver 234b, a data driver 236b, a memory 240b, a processor 270b, a power supply 290b, a current detector 510b, and the like.

[0141] The display 180b receives an image signal Vdb, a first DC voltage V1b and a second DC voltage V2b and can display a specific image based on the image signal Vdb.

[0142] Meanwhile, the first interface 230b in the display 180b may receive the image signal Vdb and the first DC voltage V1b from the signal processing device 170b.

[0143] The first DC voltage V1b can be used to operate the power supply 290b and the time controller 232b in the display 180b.

[0144] Subsequently, the second interface 231b can receive a second DC voltage V2b from an external power supply 190b. Furthermore, the second DC voltage V2b can be input to the data driver 236b in the display 180b.

[0145] The timing controller 232b may output a data drive signal Sdab and a gate drive signal Sgab based on the image signal Vdb.

[0146] For example, when the first interface 230b converts the input image signal Vdb and outputs the converted image signal va1b, the timing controller 232b may output the data drive signal Sdab and the gate drive signal Sgab based on the converted image signal va1b.

[0147] The timing controller 232b may receive a control signal, a vertical synchronization signal Vsyncb, and the like in addition to the image signal Vdb from the signal processing device 170b.

[0148] In addition to the image signal Vdb, the timing controller 232b generates a gate drive signal Sgab for operating the gate driver 234b and a data drive signal Sdab for operating the data driver 236b based on a control signal, a vertical synchronization signal Vsyncb, and the like.

[0149] If the panel 210b includes an RGBW subpixel, the data drive signal Sdab may be a data drive signal for driving the RGBW subpixel.

[0150] Meanwhile, the timing controller 232b may output a control signal Csb to the gate driver 234b.

[0151] The gate driver 234b and the data driver 236b supply a scanning signal and an image signal to the organic light-emitting panel 210b via a gate line GLb and a data line DLb, respectively, in accordance with the gate drive signal Sgab and the data drive signal Sdab from the timing controller 232b. Accordingly, the organic light-emitting panel 210b displays a specific image.

[0152] At the same time, the panel 210b may include an organic light-emitting layer. To display an image, a plurality of gate lines GLb and data lines DLb may be arranged in a matrix form in each pixel corresponding to the organic light-emitting layer.

[0153] Meanwhile, the data driver 236b may output a data signal to the organic light-emitting panel 210b based on a second DC voltage V2b from the second interface 231b.

[0154] The power supply 290b can provide various power supplies for the gate driver 234b, the data driver 236b, the timing controller 232b, etc.

[0155] Current detector 510b may detect the current flowing in a subpixel of panel 210b. The detected current may be input to processor 270b or the like to perform a cumulative current calculation.

[0156] Processor 270b may perform any type of control of display 180b. For example, processor 270b may control gate driver 234b, data driver 236b, timing controller 232b, and the like.

[0157] Meanwhile, the processor 270b may receive current information from the current detector 510b flowing in a subpixel of the plate 210b.

[0158] Fig. 6A and Fig. 6B are diagrams referred to in the description of an organic light-emitting panel of Fig. 5 is referred to.

[0159] Fig. 6A is a diagram showing a pixel in the organic light emitting panel 210b.

[0160] As shown in the figure, the organic light-emitting panel 210b may include a plurality of scanning lines (scan lines) Scan1 to Scann and a plurality of data lines R1, G1, B1, W1 to Rm, Gm, Bm, Wm that intersect the scanning lines.

[0161] Furthermore, a pixel (subpixel) is defined at an intersection of the scan line and the data line in the organic light-emitting panel 210b. In the figure, a pixel is shown with the RGBW subpixels SR1, SG1, SB1, and SW1.

[0162] Fig. 6B illustrates a circuit of any sub-pixel in the pixel of the organic light emitting panel of Fig. 6A.

[0163] As shown in the figure, an organic light-emitting subpixel circuit CRTm may include, as an active type, a scanning switching element SW1, a storage capacitor Cst, a driving switching element SW2, and an organic light-emitting layer OLED.

[0164] The scanning switching element SW1 is turned on in response to the input scanning signal Vdscan, as a scanning line is connected to a gate terminal. When it is turned on, the input data signal Vdata is transmitted to the gate terminal of a driver switching element SW2 or to one end of the storage capacitor Cst.

[0165] The storage capacitor Cst is formed between the gate terminal and the source terminal of the driver switching element SW2 and stores a certain difference between a data signal level transmitted to one end of the storage capacitor Cst and a DC voltage level (VDD) transmitted to the other terminal of the storage capacitor Cst.

[0166] For example, if the data signal has a different level according to a PAM (Plume Amplitude Modulation) method, the power level stored in the storage capacitor Cst varies according to the level difference of the data signal Vdata.

[0167] Another example: If the data signal has a different pulse width according to a pulse width modulation (PWM) method, the power level stored in the storage capacitor Cst varies according to the pulse width difference of the data signal Vdata.

[0168] The drive switching element SW2 is turned on depending on the power stored in the storage capacitor Cst. When the drive switching element SW2 is turned on, the drive current (IOLED), which is proportional to the stored power level, flows in the organic light-emitting layer (OLED). Accordingly, the organic light-emitting layer (OLED) performs a light-emitting operation.

[0169] The organic light-emitting layer (OLED) may include an RGBW light-emitting layer (EML) corresponding to a subpixel, and may include at least one of the following layers: a hole-injecting layer (HIL), a hole-transporting layer (HTL), an electron-transporting layer (ETL), and an electron-injecting layer (EIL). Furthermore, it may include a hole-blocking layer and the like.

[0170] In the organic light-emitting diode (OLED), the subpixels emit white light. However, in the case of green, red, and blue subpixels, each subpixel is provided with a separate color filter for color implementation. This means that in the case of green, red, and blue subpixels, each of the subpixels also contains green, red, and blue color filters. Since a white subpixel emits white light, a separate color filter is not required.

[0171] The figure shows that a p-type MOSFET is used for a sensing switching element SW1 and a driving switching element SW2, but an n-type MOSFET or other switching element, such as a JFET, IGBT, SIC or the like, is also possible.

[0172] Furthermore, the pixel is a hold-type element that continuously emits light in the organic light-emitting device (OLED) after a scanning signal is applied during a unit display period, particularly during a unit image.

[0173] Fig. 7 is an exemplary internal block diagram of an image display device according to an embodiment of the present disclosure.

[0174] Referring to the drawings, the image display device 100 according to an embodiment of the present disclosure includes a display 180, a signal processing device 170 configured to output an image signal to the display 180, and a converter 910 configured to supply a display drive voltage to the display 180.

[0175] The power supply 190 according to an embodiment of the present disclosure may include an AC-to-DC converter 905 (AC / DC converter) for converting an input AC voltage to a DC voltage and a DC-to-DC converter 910 (DC / DC converter) for converting the level of the DC voltage from the AC-to-DC converter 905 to output a display drive voltage Vdd.

[0176] The figure shows that the AC-to-DC converter 905 is arranged between a node n2, which is an input terminal of the power supply 190, and an input node n3 of the DC-to-DC converter 910.

[0177] Furthermore, an output node n1 of the AC / DC converter 905 can be electrically connected to the display 180.

[0178] The AC / DC converter 905 may include a diode or a switching element and convert and output an input AC voltage Va into a DC voltage having a first level.

[0179] The DC-DC converter 910 can convert a first-level input DC voltage and output a second-level display drive voltage VDD.

[0180] For example, the converter 910 may increase the first level DC voltage and output the second level display drive voltage Vdd higher than the first level.

[0181] If the display 180 is an organic light-emitting panel, the display drive voltage Vdd may be a pixel drive voltage for an organic light-emitting pixel.

[0182] However, if the display 180 is an inorganic light-emitting panel, the display drive voltage Vdd may be a pixel drive voltage for an inorganic light-emitting pixel.

[0183] However, if the display 180 is a liquid crystal panel, the display drive voltage Vdd may be a backlight control voltage or a liquid crystal pixel control voltage.

[0184] Furthermore, the image display device 100 according to an embodiment of the present disclosure further includes a main board 900 having a signal processing device 170 and a microcomputer 173.

[0185] The signal processing device 170 can output an image signal to the display 180.

[0186] Upon receiving a remote control signal, the microcomputer 173 can be operated to control the operation of the signal processing device 170 or the power supply 190.

[0187] The power supply 190 according to an embodiment of the present disclosure may output a microcomputer drive voltage Vst for operating the microcomputer 173.

[0188] For this purpose, the power supply 190 according to an embodiment of the present disclosure may further include a second DC-DC converter 915 for converting a first-level input DC voltage into a third-level microcomputer drive voltage Vst.

[0189] At this time, the microcomputer drive voltage Vst may be lower than the display drive voltage Vdd.

[0190] Furthermore, the main board 900 or the signal processing device 170 may output a display turn-on signal Spo or a display turn-off signal Spf to the power supply 190.

[0191] Accordingly, the DC-DC converter 910 may operate when the display 180 is turned on, and the DC-DC converter 910 may stop operating when the display 180 is turned off.

[0192] On the one hand, the main board 900 or the signal processing device 170 can output a switching control signal SSwa to the AC-DC converter 905. Accordingly, the AC-DC converter 905 can be stably controlled.

[0193] On the other hand, the main board 900 or the signal processing device 170 can output a switching control signal SSwb to the DC-DC converter 910. Accordingly, the DC-DC converter 910 can be operated stably.

[0194] On the other hand, the main board 900 or the signal processing device 170 can output a switching control signal SSwc to the second DC-DC converter 915. Accordingly, the second DC-DC converter 915 can be stably controlled.

[0195] The power supply 190 may also include a signal generator FDK connected between the converter 910 and the main board 900.

[0196] The signal generator FDK can receive a display turn-on signal Spo or a display turn-off signal Spf from the main board 900 including the signal processing device 170 or from the signal processing device 170 and transmit the display turn-on signal Spo or the display turn-off signal Spf to the converter 910.

[0197] Fig. 8 is an exemplary circuit diagram of a power supply related to the present disclosure.

[0198] As shown in the drawing, a power supply 190x in accordance with the present disclosure includes a converter 910x configured to output a display drive voltage.

[0199] The converter 910x includes switching elements SW1 and SW2 arranged at an input terminal of the transformer 805 and connected in series with each other, a capacitor Cr and an inductor Lr arranged between the switching element SW2 and the transformer 805, full-bridge diodes arranged at an output terminal of the transformer 805, a capacitor element Cd arranged at an output terminal of the full-bridge diodes, a resistance element Rd arranged at both ends of the capacitor element Cd, and a switching controller 825.

[0200] The resistive element Rd in the 910x converter is arranged to reduce the increase in output voltage at low load or idle, but there is a problem that the resistive element Rd consumes current regardless of the load, resulting in unnecessary power consumption.

[0201] However, if the 910x converter does not contain a resistive element Rd, the output voltage increases at low load or idle.

[0202] Accordingly, the present disclosure proposes a method for preventing the increase of the output voltage at low load or no-load without incorporating the resistance element in the converter, which will be described below with reference to Fig. 9 and the following figures.

[0203] Fig. 9 is an exemplary circuit diagram of a power supply according to an embodiment of the present disclosure.

[0204] Referring to the drawing, the power supply 190 according to an embodiment of the present disclosure includes a converter 910 including switching elements SW1 and SW2 and configured to convert a level of an input DC voltage based on a switching operation of the switching elements SW1 and SW2 to output a display drive voltage Vdd.

[0205] The converter 910 according to an embodiment of the present disclosure operates in a first mode or a second mode in response to a load at an output terminal of the converter 910, wherein in the first mode, the switching elements SW1 and SW2 perform a continuous switching operation at a first frequency, and in a second mode, the switching elements SW1 and SW2 perform the continuous switching operation and then stop the switching operation for a predetermined period of time or perform the switching operation at a second frequency lower than the first frequency.

[0206] Accordingly, it is possible to reduce the output voltage rise at light loads or idle. Furthermore, the display drive voltage Vdd can be provided stably. Furthermore, the power consumption of the 190 power supply can be reduced.

[0207] Furthermore, when a load at the output terminal of the converter 910 is less than or equal to a reference value, the converter 910 can operate in the second mode, in which the switching elements SW1 and SW2 perform the continuous switching operation and then pause the switching operation for a predetermined period of time or perform the switching operation at the second frequency. Accordingly, it is possible to reduce the increase in the output voltage under light load or no-load conditions.

[0208] If the load at the output terminal of converter 910 exceeds the reference value, converter 910 can operate in the first operating mode, in which switching elements SW1 and SW2 perform a continuous switching operation at the first frequency. Accordingly, a display voltage can be stably output under medium or high load conditions.

[0209] Alternatively, the converter 910 may operate in the first mode, in which the switching elements SW1 and SW2 perform the continuous switching operation at the first frequency, when a load at the output terminal of the converter 910 is greater than or equal to a second reference value that is greater than the reference value. Accordingly, a display voltage can be stably output under medium or high load conditions.

[0210] When a black image is displayed on the display 180, the converter 910 can operate in the second mode, in which the switching elements SW1 and SW2 perform the continuous switching operation and then pause the switching operation for a predetermined period of time or perform the switching operation at the second frequency. Accordingly, it is possible to reduce the increase in the output voltage when a black image is displayed.

[0211] In another example, when a gray image with a gray value less than or equal to a predetermined value is displayed on the display 180, the converter 910 may operate in the second mode in which the switching elements SW1 and SW2 perform the continuous switching operation and then pause the switching operation for a predetermined period of time or perform the switching operation at the second frequency. Accordingly, it is possible to reduce the increase in the output voltage when a gray image is displayed.

[0212] In another example, converter 910 may operate in the first mode, in which switching elements SW1 and SW2 perform the continuous switching operation at the first frequency when a white image is displayed on display 180. Accordingly, a display voltage may be stably output under medium or high load conditions.

[0213] Furthermore, the converter 910 may include a transformer 805, a first switching element SW1 and a second switching element SW2 arranged at an input terminal of the transformer 805 and connected in series with each other, and a resonant capacitor Cr and a resonant inductor Lr arranged between and connected to the input terminal of the transformer 805 and the second switching element SW2. Accordingly, the display drive voltage Vdd can be output based on resonance.

[0214] Meanwhile, converter 910 may also include full-bridge diodes at the output terminal of transformer 805 and a capacitor element Cd at the output terminal of the full-bridge diodes. Accordingly, display drive voltage Vdd can be stably output based on resonance.

[0215] Furthermore, it is desirable that the resistance element is not arranged at both ends of the capacitor element Cd. Compared to Fig. 8, the resistance element Rd is not arranged, so unnecessary power consumption due to the resistance element Rd can be reduced. Accordingly, the power consumption of the power supply 190 can be reduced.

[0216] The converter 910 may also include a voltage detection circuit 935 configured to detect a voltage across the second switching element SW2.

[0217] When the voltage at the second switching element SW2 detected by the voltage detection circuit 935 is zero, the converter 910 can turn on the second switching element SW2. Accordingly, it is possible to reduce noise by performing zero-voltage switching of the second switching element SW2.

[0218] During operation in the second mode, converter 910 can turn on second switching element SW2 when the voltage across second switching element SW2 detected by voltage detection circuit 935 is zero voltage. Accordingly, it is possible to reduce noise by performing zero-voltage switching of second switching element SW2.

[0219] Furthermore, the voltage detection circuit 935 may include a capacitor Ct connected to a first node nm between the first switching element SW1 and the second switching element SW2, a Zener diode Dt arranged between the capacitor Ct and a ground terminal, and a resistance element Rt, one end of which is connected to a second node nb between the capacitor Ct and the Zener diode Dt. Accordingly, the voltage at the second switching element SW2 can be stably detected.

[0220] Furthermore, the converter 910 may also include a switching controller 925 configured to control the first switching element SW1 and the second switching element SW2.

[0221] Furthermore, the switching controller 925 can control the zero-voltage switching of the second switching element SW2 based on a voltage at the second node nb. Accordingly, it is possible to reduce noise by switching the second switching element SW2 to a zero-voltage state.

[0222] When a mode for turning on the power supply of the display is selected in a setting screen, the signal processing device 170 may control the power supply 190 to supply a display drive voltage of a first level to the display 180.

[0223] When a mode for turning off the power supply of the display is selected in the setting screen, the signal processing device 170 may control the power supply 190 to supply a display drive voltage of a second level to the display 180.

[0224] When the display power-on mode is selected in the setting screen, the signal processing device 170 may control the power supply 190 to supply the first-level display drive voltage to the display 180 based on the second operation mode.

[0225] When the display power off mode is selected in the setting screen, the signal processing device 170 may control the power supply 190 to supply the second level display drive voltage to the display 180 based on the first operation mode.

[0226] In this case, the second-level display drive voltage is desirably larger than the first-level display drive voltage. Accordingly, different display drive voltages can be stably provided in different operating modes.

[0227] When the eco or standard mode is selected in the setting screen, the signal processing device 170 may control the power supply 190 to supply the first level display drive voltage to the display 180.

[0228] When the cinema mode or the game mode is selected on the setting screen, the signal processing device 170 may control the power supply 190 to supply the second level display drive voltage to the display 180.

[0229] Furthermore, according to an embodiment of the present disclosure, the power supply 190 varies the level of the display drive voltage based on the image output mode of the signal processing device 170.

[0230] In particular, the power supply 190 outputs a higher display drive voltage in the cinema mode or the game mode than in the eco mode of the signal processing device 170. Accordingly, different display drive voltages can be stably provided in different modes.

[0231] Fig. 10A to 13C are diagrams referred to in the description of Fig. 9 is referred to.

[0232] Fig. 10A is a diagram showing a waveform of a switching control signal for operating the converter of Fig. 9 in a first operating mode.

[0233] As shown in the drawing, during operation in the first mode, the switching controller 925 may output a first switching control signal SS1a for the first switching element SW1 and a second switching control signal SS2a for the second switching element SW2.

[0234] In this case, the frequency of the first switching control signal SS1a for the first switching element SW1 and the second switching control signal SS2a for the second switching element SW2 may be a first frequency 1 / Pk.

[0235] Accordingly, the converter 910 can stably output the display drive voltage Vdd in the first operation mode.

[0236] Fig. Figure 10B is a diagram showing a waveform of a switching control signal for operating the converter of Fig. 9 in a second operating mode.

[0237] As shown in the drawing, during operation in the second mode, the switching controller 925 may output a first switching control signal SS1b for the first switching element SW1 and a second switching control signal SS2b for the second switching element SW2.

[0238] In this case, the frequency of the first switching control signal SS1b for the first switching element SW1 and the second switching control signal SS2b for the second switching element SW2 may be a second frequency 1 / Pkm which is lower than the first frequency.

[0239] Accordingly, during operation in the second mode, the converter 910 may reduce the increase in output voltage at low load or idle.

[0240] As opposed to Fig. 10B, during operation in the second mode, the switching controller 925 may also turn off the first switching element SW1 and the second switching element SW2 for a predetermined period of time after the switching operation is performed at the first frequency. Accordingly, it is possible to reduce the increase in the output voltage at low load or idle.

[0241] Furthermore, the second frequency in the second operating mode may correspond to a frequency outside the audible frequency range. For example, the second frequency may be a frequency of 20 kHz or higher. Accordingly, it is possible to reduce the output voltage rise at light load or idle while simultaneously reducing noise.

[0242] Furthermore, the first frequency in the first operating mode can also correspond to a frequency outside the audible frequency range. For example, the first frequency can be a frequency of 20 kHz or higher. Accordingly, a display voltage can be output stably under medium or high load while reducing noise.

[0243] Fig. 11A is a diagram illustrating the relationship between a voltage of a second switching element and a current generated by switching the second switching element.

[0244] As in (a) of Fig. As shown in Figure 11A, a voltage across the second switching element SW2 or a voltage Vdsm between drain and source can be changed from a high level to a low level.

[0245] Furthermore, as in (b) of Fig. 11A, a second switching control signal SSw2m for the second switching element SW2 may be input to a gate terminal of the second switching element SW2.

[0246] Meanwhile, at a time Tk1, the second switching control signal SSw2m is changed to a high level, so that the second switching element SW2 is turned on, the voltage Vdsm between the drain and source of the second switching element SW2 is not a zero voltage but a high level voltage, so that a current idm with an instantaneous peak level Lpk flows through the second switching element SW2, as shown in (c) of Fig. 11A.

[0247] The current idm with the instantaneous peak level Lpk causes noise.

[0248] Meanwhile, at a time Tk2, the second switching control signal SSw2m is changed to a high level, so that the second switching element SW2 is turned on, the voltage Vdsm between the drain and source of the second switching element SW2 is a zero voltage, so that a current idm with an instantaneous peak level Lpm much lower than Lpk flows through the second switching element SW2.

[0249] Accordingly, in the present disclosure, the zero-voltage switching is controlled to be performed when the second switching element SW2 is turned on.

[0250] Fig. 11B is a diagram showing an example of switching of the second switching element SW2.

[0251] Referring to the drawing, (a) in Fig. 11B a voltage Vdsn between drain and source of the second switching element SW2.

[0252] That is, the voltage is maintained at a high level in each of the intervals Poa, Pob and Poc and can be represented as a sine function in an interval Pra between Poa and Pob and an interval Prb between Pob and Poc.

[0253] In Fig. 11b, (c) and (d) may be a first switching control signal SSw1n for the first switching element SW1 and a second switching control signal SSw2n for the second switching element SW2, respectively.

[0254] When the second switching control signal SSw2n for the second switching element SW2 is changed to a high level at a time Tn, the second switching element SW2 is turned on, but a voltage Vdsn between the drain and source of the second switching element SW2 is not a zero voltage, so that a current idn having a peak level is generated as shown in (b) of Fig. 11B, which causes noise.

[0255] Fig. 11C is a diagram showing an example of the zero-voltage circuit of the second switching element SW2.

[0256] Referring to the drawing, (a) in Fig. 11C a voltage Vdsp between drain and source of the second switching element SW2.

[0257] That is, the voltage is maintained at a high level in each of the intervals Poa, Pob and Poc and can be represented as a sine function in an interval Pra between Poa and Pob and an interval Prb between Pob and Poc.

[0258] In Fig. 11C, (c) and (d) may be a first switching control signal SSw1p for the first switching element SW1 and a second switching control signal SSw2p for the second switching element SW2, respectively.

[0259] When the second switching control signal SSw2p for the second switching element SW2 is changed to a high level at a time To, the second switching element SW2 is turned on, but a voltage Vdsp between the drain and the source of the second switching element SW2 is a zero voltage, so that a current idp at a predetermined level is generated as shown in (b) of Fig. 11C, which causes no noise or significantly reduces the noise.

[0260] For zero-voltage switching, the switching controller 925 can receive, in real time, a voltage across the second switching element SW2 or a voltage between the drain and source of the second switching element SW2 from the voltage detection circuit 935, which detects the voltage across the second switching element SW2. Accordingly, the zero-voltage switching can be performed stably.

[0261] Furthermore, in the image display device 100 according to another embodiment of the present disclosure, the converter 910 operates in a first operating mode or a second operating mode in response to a load at the output terminal of the converter 910, wherein in the first operating mode, the switching elements SW1 and SW2 perform a continuous switching operation with a first duty cycle Gp, and in a second operating mode, the switching elements SW1 and SW2 perform a switching operation with a second duty cycle GPb that is less than the first duty cycle. This will be described below with reference to Fig. 12A and Fig. 12B.

[0262] Fig. 12A is a diagram showing a switching control signal having a first duty cycle.

[0263] As shown in the drawing, the switching controller 925 may control the first switching element SW1 and the second switching element SW2 to perform a switching operation with the first duty cycle GP.

[0264] In the drawing, a first switching control signal Ssw1a and a second switching control signal Ssw2a are shown based on the first duty cycle GP.

[0265] If a load at the output terminal of the converter 910 exceeds a reference value, the converter 910 can switch the switching elements SW1 and SW2 with the first duty cycle GP.

[0266] Furthermore, the converter 910 may switch the switching elements SW1 and SW2 with the first duty cycle GP when a load at the output terminal of the converter 910 is greater than or equal to a second reference value that is greater than the reference value.

[0267] When a white image is displayed on the display 180, the converter 910 can operate in the first mode to switch the switching elements SW1 and SW2 with the first duty cycle GP. Accordingly, the display drive voltage can be stably output when the white image is displayed.

[0268] Fig. 12B is a diagram showing a switching control signal with a second duty cycle.

[0269] As shown in the drawing, the switching controller 925 may control both the first switching element SW1 and the second switching element SW2 to perform a switching operation with the second duty cycle GPb.

[0270] The drawing shows a first switching control signal Ssw1c and a second switching control signal Ssw2c based on the second duty cycle GPb.

[0271] Furthermore, the second duty cycle GPb is desirably smaller than the first duty cycle GP.

[0272] In the drawing, of the ON time Gpb and the OFF time Gpa of the first duty cycle, GP corresponds to the ON time of the second duty cycle.

[0273] When the load at the output terminal of the converter 910 is less than or equal to a reference value, the converter 910 may switch the switching elements SW1 and SW2 with the second duty cycle GPb.

[0274] Furthermore, the converter 910 may switch the switching elements SW1 and SW2 with the first duty cycle GP when a load at the output terminal of the converter 910 is greater than or equal to a second reference value that is greater than the reference value.

[0275] When a black image is displayed on the display 180, the converter 910 can operate in the second mode to switch the switching elements SW1 and SW2 with the second duty cycle GPb. Accordingly, it is possible to reduce the increase in the output voltage when the black image is displayed.

[0276] Fig. 13A is a diagram showing an example in which a black image 1310 is displayed on the display 180.

[0277] Referring to the drawing, when the black image 1310 is displayed on the display 180, the converter 910 according to an embodiment of the present disclosure may operate in the second mode in which the switching elements SW1 and SW2 perform a continuous switching operation and then pause the switching operation for a predetermined period of time or perform the switching operation at the second frequency. Accordingly, it is possible to reduce the increase in the output voltage when the black image is displayed.

[0278] Furthermore, when the black image 1310 is displayed on the display 180, the converter 910 according to another embodiment of the present disclosure may operate in the second mode to switch the switching elements SW1 and SW2 with the second duty cycle GPb.

[0279] Fig. 13B is a diagram showing an example in which a predetermined image 1320 is displayed on the display 180.

[0280] Referring to the drawing, the converter 910 according to an embodiment of the present disclosure may operate in the first mode in which the switching elements SW1 and SW2 perform a continuous switching operation at the first frequency when the predetermined image 1320 is displayed on the display 180 and a load at the output terminal of the converter 910 exceeds a reference value. Accordingly, it is possible to reduce the increase in the output voltage when the black image is displayed.

[0281] According to another embodiment of the present disclosure, when the predetermined image 1320 is displayed on the display 180 and a load at the output terminal of the converter 910 exceeds the reference value, the converter 910 may operate in the first mode for switching the switching elements SW1 and SW2 with the first duty cycle GP.

[0282] Fig. 13C is a diagram showing an example where a gray image 1330 is displayed on the display 180.

[0283] Referring to the drawing, the converter 910 according to an embodiment of the present disclosure may operate in the second mode in which the switching elements SW1 and SW2 perform a continuous switching operation and then stop the switching operation for a predetermined period of time or perform the switching operation at the second frequency when the gray image 1330 with a gray value less than or equal to a predetermined value is displayed on the display 180. Accordingly, it is possible to reduce the increase in the output voltage when the gray image is displayed.

[0284] Furthermore, when the gray image 1330 having a gray value less than or equal to a predetermined value is displayed on the display 180, the converter 910 according to another embodiment of the present disclosure may operate in the second mode for switching the switching elements SW1 and SW2 with the second duty cycle GPb.

[0285] Fig. 14A to 14D are flowcharts illustrating an operation method of an image display device according to various embodiments of the present disclosure.

[0286] Fig. 14A is a flowchart illustrating an operation method of an image display device according to an embodiment of the present disclosure.

[0287] Referring to the drawing, in the image display device 100 according to an embodiment of the present disclosure, the converter 910 or the signal processing device 170 may determine (S1410) whether an operation mode is a first operation mode based on the load at the output terminal of the converter 910.

[0288] For example, the signal processing device 170 may identify a level of the load at the output terminal of the converter 910 based on a luminance level of an image to be displayed on the display 180 and transmit information about the identified load level to the switching controller 925 in the power supply 190.

[0289] When a level of the load at the output terminal of the converter 910 is less than or equal to a reference value, the signal processing device 170 or the switching controller 925 in the converter 910 may determine that the operating mode is the first operating mode.

[0290] When the load at the output terminal of converter 910 is less than or equal to the reference value, converter 910 can execute the first operating mode in which switching elements SW1 and SW2 perform a continuous switching operation at the first frequency (S1415). Accordingly, display drive voltage Vdd can be stably output to display 180.

[0291] If the operation mode is not the first operation mode in step 1410 (S1410), the converter 910 or the signal processing device 170 in the image display device 100 may determine whether a second operation mode is the operation mode based on the load at the output terminal of the converter 910 (S1420).

[0292] For example, if a level of the load at the output terminal of the converter 910 exceeds the reference value, the signal processing device 170 or the switching controller 925 in the converter 910 may determine that the operating mode is the second operating mode.

[0293] When the load at the output terminal of converter 910 exceeds the reference value, converter 910 executes the second operation mode, in which switching elements SW1 and SW2 perform the continuous switching operation and then stop the switching operation for a predetermined period of time or perform the switching operation at the second frequency lower than the first frequency (S1425). Accordingly, it is possible to reduce the increase in the output voltage under light load or idle conditions.

[0294] Fig. 14B is a flowchart showing an operation method of an image display device according to another embodiment of the present disclosure.

[0295] As shown in the drawing, in the image display device 100 according to an embodiment of the present disclosure, the converter 910 or the signal processing device 170 may determine whether a black image is displayed on the display 180 (S1411).

[0296] For example, the signal processing device 170 may determine whether an image to be displayed on the display 180 is a black image and may transmit information about the black image to the switching controller 925 in the power supply 190.

[0297] When the image to be displayed on the display 180 is not a black image, the converter 910 executes the first operation mode in which the switching elements SW1 and SW2 perform a continuous switching operation at the first frequency (S1415). Accordingly, the display drive voltage Vdd can be stably output on the display 180.

[0298] When the image to be displayed on the display 180 is a black image in step 1411 (S1411), the converter 910 in the image display device 100 executes the second operation mode in which the switching elements SW1 and SW2 perform the continuous switching operation and then pause the switching operation for a predetermined period of time or perform the switching operation at the second frequency lower than the first frequency (S1425). Accordingly, it is possible to reduce the increase in the output voltage when the black image is displayed.

[0299] Fig. 14C is a flowchart showing an operation method of an image display device according to another embodiment of the present disclosure.

[0300] Referring to the drawing, in the image display device 100 according to an embodiment of the present disclosure, the converter 910 or the signal processing device 170 may determine whether the output terminal of the converter 910 is in the idle state (S1412).

[0301] For example, if an image to be displayed on the display 180 is a black image, the signal processing device 170 may detect an idle state and transmit information about the idle state to the switching controller 925 in the power supply 190.

[0302] When the output terminal of converter 910 is not open-circuited, converter 910 executes the first operation mode, in which switching elements SW1 and SW2 perform continuous switching at the first frequency (S1415). Accordingly, display drive voltage Vdd can be stably output to display 180.

[0303] When the output terminal of converter 910 is idle in step 1412 (S1412), converter 910 in image display device 100 executes the second operation mode in which switching elements SW1 and SW2 perform the continuous switching operation and then pause the switching operation for a predetermined period of time or perform the switching operation at the second frequency lower than the first frequency (S1425). Accordingly, it is possible to reduce the increase in the output voltage when the output terminal of converter 910 is idle.

[0304] Fig. 14D is a flowchart showing an operation method of an image display device according to another embodiment of the present disclosure.

[0305] Referring to the drawing, in the image display device 100 according to an embodiment of the present disclosure, the converter 910 or the signal processing device 170 may determine (S1410) whether an operation mode is a first operation mode based on the load at the output terminal of the converter 910.

[0306] For example, when a level of the load at the output terminal of the converter 910 is less than or equal to a reference value, the signal processing device 170 or the switching controller 925 in the converter 910 may determine that the first operating mode is the operating mode.

[0307] When the load level at the output terminal of converter 910 is less than or equal to the reference value, converter 910 executes the first operating mode in which switching elements SW1 and SW2 perform a continuous switching operation with the first duty cycle Gp (S1417). Accordingly, the display drive voltage Vdd can be stably output to display 180.

[0308] If the operation mode is not the first operation mode in step 1410 (S1410), the converter 910 or the signal processing device 170 in the image display device 100 may determine whether an operation mode is a second operation mode based on the load at the output terminal of the converter 910 (S1420).

[0309] For example, if a level of the load at the output terminal of the converter 910 exceeds the reference value, the signal processing device 170 or the sound controller 925 in the converter 910 may determine that the second operating mode is the operating mode.

[0310] When the load level at the output terminal of converter 910 exceeds the reference value, converter 910 executes the second operation mode, in which switching elements SW1 and SW2 perform a switching operation with the second duty cycle GPb, which is shorter than the first duty cycle Gp (S1427). Accordingly, it is possible to reduce the increase in the output voltage at low load or idle.

[0311] As described above, an image display device according to an embodiment of the present disclosure comprises: a display; a signal processing device configured to output an image signal to the display; and a power supply configured to supply a display drive voltage to the display, wherein the power supply comprises a converter including switching elements and configured to convert a level of an input DC voltage based on a switching operation of the switching elements and output the display drive voltage, wherein the converter is configured to operate in a first operating mode in which the switching elements perform a continuous switching operation at a first frequency, and in a second operating mode in response to a load at an output terminal of the converter,in which the switching elements perform the continuous switching operation and then pause the switching operation for a predetermined period of time or perform the switching operation at a second frequency that is lower than the first frequency. Accordingly, it is possible to reduce the increase in the output voltage under light load or idle conditions. In addition, the display drive voltage can be provided stably. Furthermore, the power supply's power consumption can be reduced.

[0312] Furthermore, the converter may be configured to operate in the second operating mode in response to the load at the output terminal of the converter being less than or equal to a reference value, in which the switching elements perform the continuous switching operation and then pause the switching operation for the predetermined period of time or perform the switching operation at the second frequency. Accordingly, it is possible to reduce the increase in the output voltage at low load or idle.

[0313] The converter may be configured to operate in the second operating mode in response to the display of a black image on the display, in which the switching elements perform the continuous switching operation and then pause the switching operation for the predetermined period of time or perform the switching operation at the second frequency. Accordingly, it is possible to reduce the increase in the output voltage when the black image is displayed.

[0314] Furthermore, the converter may include: a transformer; a first switching element and a second switching element arranged at an input terminal of the transformer and connected in series with each other; and a resonant capacitor and a resonant inductor arranged between the input terminal of the transformer and the second switching element and connected thereto. Accordingly, the display drive voltage can be output based on resonance.

[0315] Furthermore, the converter may further comprise full-bridge diodes arranged at an output terminal of the transformer; and a capacitor element arranged at an output terminal of the full-bridge diodes. Accordingly, the display drive voltage can be stably output based on resonance.

[0316] Furthermore, it is desirable that the resistor element is not located at both ends of the capacitor element. Accordingly, the power consumption of the power supply can be reduced.

[0317] Furthermore, the second frequency can correspond to a frequency outside the audible frequency range. Accordingly, it is possible to reduce the output voltage rise at light load or idle while simultaneously reducing noise.

[0318] The converter may further include a voltage detection circuit configured to detect a voltage across the second switching element. Accordingly, it is possible to reduce noise by switching the second switching element to zero voltage.

[0319] Furthermore, the converter may be configured to turn on the second switching element when the voltage across the second switching element detected by the voltage detection circuit is zero voltage. Accordingly, it is possible to reduce noise by performing zero-voltage switching of the second switching element.

[0320] During operation in the second mode, the converter may be configured to turn on the second switching element when the voltage at the second switching element detected by the voltage detection circuit is zero voltage. Accordingly, it is possible to reduce noise by performing zero-voltage switching of the second switching element.

[0321] Furthermore, the voltage detection circuit may include: a capacitor connected to a first node between the first switching element and the second switching element; a Zener diode disposed between the capacitor and a ground terminal; and a resistance element having one end connected to a second node between the capacitor and the Zener diode. Accordingly, the voltage at the second switching element can be stably detected.

[0322] Furthermore, the converter may further include a switching controller configured to control the first switching element and the second switching element, wherein the switching controller may be configured to control the zero-voltage switching of the second switching element based on a voltage at the second node. Accordingly, it is possible to reduce noise by performing zero-voltage switching of the second switching element.

[0323] Furthermore, the power supply may also include a second converter configured to convert an input AC voltage into a DC voltage, wherein the converter is configured to convert the DC voltage from the second converter and output the display drive voltage to the display. Accordingly, the display drive voltage can be supplied stably.

[0324] Furthermore, the signal processing device may be configured to: in response to a display voltage control mode selected in a setting screen, control the power supply to supply a display drive voltage of a first level to the display; and in response to a display power-on mode selected in the setting screen, control the power supply to supply a display drive voltage of a second level to the display. Accordingly, different display drive voltages can be stably provided in different operating modes.

[0325] Furthermore, the signal processing device may be configured to: in response to a display power-on mode selected in a setting screen, control the power supply to supply the first-level display drive voltage to the display based on the second operating mode; and in response to a display power-off mode selected in the setting screen, control the power supply to supply the second-level display drive voltage to the display based on the first operating mode. Accordingly, different display drive voltages can be stably supplied in different operating modes.

[0326] An image display device according to another embodiment of the present disclosure comprises: a display; a signal processing device configured to output an image signal to the display; and a power supply configured to supply a display drive voltage to the display, wherein the power supply includes a converter including switching elements and configured to convert a level of an input DC voltage based on a switching operation of the switching elements and output the display drive voltage, wherein the converter is configured to operate in response to a load at an output terminal of the converter in a first operating mode in which the switching elements perform a continuous switching operation with a first duty cycle, and in a second operating mode in which the switching elements perform the switching operation with a second duty cycle.which is less than the initial duty cycle. This makes it possible to reduce the output voltage increase under light load or idle conditions. It also allows for a stable display drive voltage. Furthermore, the power consumption of the power supply can be reduced.

[0327] The converter may be configured to operate in the second operating mode when the load at the output terminal of the converter is less than or equal to a reference value, in which the switching elements perform the switching operation with the second duty cycle. Accordingly, it is possible to reduce the increase in the output voltage at low load or idle.

[0328] The converter may be configured to operate in the second operating mode in response to the display of a black image on the display, in which the switching elements perform the switching operation with the second duty cycle. Accordingly, it is possible to reduce the increase in the output voltage when the black image is displayed.

[0329] Furthermore, the converter may include: a transformer; a first switching element and a second switching element arranged at an input terminal of the transformer and connected in series with each other; and a resonant capacitor and a resonant inductor arranged between and connected to the input terminal of the transformer and the second switching element. Accordingly, the display drive voltage can be stably output based on resonance.

[0330] It will be appreciated that, although the preferred embodiments have been illustrated and described above, the present disclosure is not limited to the specific embodiments described above, and that various modifications and variations may be made by those skilled in the art without departing from the spirit of the appended claims. Therefore, it is intended that the modifications and variations should not be understood independently of the technical spirit or perspective of the present disclosure.

Claims

[1] An image display device (100) comprising: an advertisement (180); a signal processing device (170) configured to output an image signal to the display; and a power supply (190) configured to supply a display drive voltage to the display, wherein the power supply (190) comprises a converter (910) containing switching elements and configured to convert a level of an input DC voltage based on a switching operation of the switching elements and output the display drive voltage, wherein the converter (910) is configured to operate in response to a load at an output terminal of the converter in a first operating mode in which the switching elements perform a continuous switching operation at a first frequency, and in a second operating mode in which the switching elements perform the continuous switching operation and then stop the switching operation for a predetermined period of time or perform the switching operation at a second frequency which is lower than the first frequency. [2] The image display device according to claim 1, wherein the converter (910) is configured to operate in the second mode in which the switching elements perform the continuous switching operation and then stop the switching operation for the predetermined period of time or perform the switching operation at the second frequency in response to the load at the output terminal of the converter being less than or equal to a reference value. [3] An image display device according to claim 1 or 2, wherein the converter (910) is arranged to operate in the second mode in response to a black image displayed on the display, in which the switching elements perform the continuous switching operation and then stop the switching operation for the predetermined period of time or perform the switching operation at the second frequency. [4] An image display device according to any one of claims 1 to 3, wherein the converter (910) comprises: a transformer (805); a first switching element (SW1) and a second switching element (SW2) arranged at an input terminal of the transformer and connected in series; and a resonance capacitor (Cr) and a resonance inductance (Lr) arranged between or connected to the input terminal of the transformer (805) and the second switching element (SW2). [5] An image display device according to claim 4, wherein the converter further comprises: Full-bridge diodes arranged at an output terminal of the transformer; and a capacitor element arranged at an output terminal of the full-bridge diodes. [6] The image display device according to claim 4 or 5, wherein the converter (910) further comprises a voltage detection circuit (935) configured to detect a voltage across the second switching element. [7] The image display device according to claim 6, wherein the converter (910) is configured to turn on the second switching element when the voltage across the second switching element detected by the voltage detection circuit is a zero voltage. [8] The image display device according to claim 6 or 7, wherein the converter (910) is configured to turn on the second switching element during operation in the second mode in response to the voltage across the second switching element detected by the voltage detection circuit being a zero voltage. [9] An image display device according to any one of claims 6 to 8, wherein the voltage detection circuit (935) comprises: a capacitor (Ct) connected to a first node (nm) between the first switching element and the second switching element; a Zener diode (Dt) arranged between the capacitor and a ground terminal; and a resistive element (Rt) having one end connected to a second node between the capacitor and the Zener diode. [10] The image display device according to claim 9, wherein the converter (910) further comprises a switching controller (925) configured to control the first switching element and the second switching element, wherein the switching controller is configured to control a zero-voltage switching of the second switching element based on a voltage at the second node. [11] The image display device according to any one of claims 1 to 10, wherein the power supply (190) further comprises a second converter (905) configured to convert an input AC voltage into a DC voltage, wherein the converter (910) is configured to convert the DC voltage from the second converter (905) and output the display drive voltage to the display. [12] Image display device according to one of claims 1 to 11, wherein the signal processing device (170) is arranged to: in response to a selection of a mode for turning on the power supply of the display in a settings screen, control the power supply to supply a display drive voltage having a first level to the display; and in response to a selection of a display power off mode in the settings screen, control the power supply to supply a display drive voltage having a second level to the display. [13] Image display device according to one of claims 1 to 12, wherein the signal processing device (170) is arranged to: in response to a selection of a mode for turning on the power supply of the display in a setting screen, control the power supply so that the display drive voltage at the first level is supplied to the display based on the second operating mode; and in response to selecting a display power off mode in the setting screen, control the power supply to supply the display drive voltage at the second level to the display based on the first operating mode.

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