Image display device and video wall having same

Abstract

The present disclosure relates to an image display device and a video wall having same. An image display device according to one embodiment of the present disclosure comprises: a first light-emitting diode that emits light of a first color; a second light-emitting diode that emits light of a second color; a third light-emitting diode that emits light of a third color; a first switching element connected to an anode of the first light-emitting diode; a second switching element connected to an anode of the second light-emitting diode; a third switching element connected to an anode of the third light-emitting diode; a scan switching element connected to cathodes of the first to third light-emitting diodes; and a driving controller that outputs a scan signal to the scan switching element for each of a plurality of sub-frame periods and outputs a pulse-width-variable-based data signal to the first to third switching elements, wherein the driving controller outputs a first data signal of a first level to the first switching element, outputs a second data signal of a second level, which is greater than the first level, to the second switching element, and outputs a third data signal of a third level, which is less than the first level and greater than half of the first level, to the third switching element. Accordingly, the color expressivity of the light-emitting diodes may be enhanced.

Description

Video display device and video wall equipped with the same

[0001] The present disclosure relates to an image display device and a video wall equipped with the same, and more specifically, to an image display device capable of increasing the color expression capability of a light-emitting diode and a video wall equipped with the same.

[0002] A video display device is a device that displays an image by having a display.

[0003] Meanwhile, various types of displays, such as liquid crystal display panels and light-emitting diode panels, are used in video display devices.

[0004] Meanwhile, when configuring a video display device based on a light-emitting diode panel, an active matrix driving method or a passive matrix driving method is used to drive the light-emitting diode panel.

[0005] When driving a light-emitting diode panel-based image display device based on a passive matrix driving method, multiple subframes are used to light up or de-light the light-emitting diodes.

[0006] Meanwhile, when applying pulse-width variable-based data signals to emit red light-emitting diodes, green light-emitting diodes, and blue light-emitting diodes, there is a problem in that the color expression power of the light-emitting diodes is reduced because the efficiency of each light-emitting diode is different.

[0007] The problem to be solved by the present disclosure is to provide an image display device capable of increasing the color expression capability of a light-emitting diode and a video wall equipped with the same.

[0008] Another problem that the present disclosure aims to solve is to provide an image display device capable of increasing the low-gradation color expression capability of a light-emitting diode and a video wall equipped with the same.

[0009] Another problem that the present disclosure aims to solve is to provide an image display device capable of increasing the current efficiency of a light-emitting diode and a video wall equipped with the same.

[0010] A video display device and a video wall equipped with the same according to an embodiment of the present disclosure for achieving the above-mentioned problem comprises: a first light-emitting diode that outputs light of a first color; a second light-emitting diode that outputs light of a second color; a third light-emitting diode that outputs light of a third color; a first switching element connected to the anode of the first light-emitting diode; a second switching element connected to the anode of the second light-emitting diode; a third switching element connected to the anode of the third light-emitting diode; a scan switching element connected to the cathodes of the first to third light-emitting diodes; and a driving control unit that outputs a scan signal to the scan switching element for a plurality of sub-frame periods and outputs a pulse width variable-based data signal to the first to third switching elements. The driving control unit outputs a first data signal of a first level to the first switching element, outputs a second data signal of a second level greater than the first level to the second switching element, and outputs a third data signal of a third level smaller than the first level and greater than half of the first level to the third switching element.

[0011] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element, output a second data signal of a second level and a first pulse width to a second switching element, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element.

[0012] Meanwhile, the driving control unit can control the second pulse width to be half the first pulse width when displaying a white image.

[0013] Meanwhile, the drive control unit can control the second level to be twice the first level or the second level to be three times the third level.

[0014] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element based on a first clock frequency, output a second data signal of a second level and a first pulse width to a second switching element based on a first clock frequency, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a first clock frequency.

[0015] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element based on a first clock frequency, output a second data signal of a second level and a first pulse width to a second switching element based on a first clock frequency, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a second clock frequency which is greater than the first clock frequency.

[0016] Meanwhile, the drive control unit can control the second clock frequency to be twice the first clock frequency.

[0017] Meanwhile, the driving control unit can control the level of the current flowing through the third light-emitting diode to reach the first current within the first clock cycle from the time the third switching element turns on.

[0018] Meanwhile, the driving control unit can set a third level such that, within a first clock cycle from the turn-on time of the third switching element, the level of the current flowing through the third light-emitting diode reaches a first current.

[0019] Meanwhile, the driving control unit can control the voltage across the third light-emitting diode to exceed the forward voltage within the first clock cycle from the turn-on time of the third switching element.

[0020] Meanwhile, the driving control unit can set a third level such that, within a first clock cycle from the turn-on time of the third switching element, the voltage across the third light-emitting diode exceeds the forward voltage.

[0021] Meanwhile, the driving control unit includes a frequency selector that selects a first clock frequency or a second clock frequency that has a frequency greater than the first clock frequency, and outputs a first data signal of a first level and a first pulse width to a first switching element based on the first clock frequency, outputs a second data signal of a second level and a first pulse width based on the first clock frequency, and outputs a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a second clock frequency that has a frequency greater than the first clock frequency.

[0022] An image display device and a video wall equipped with the same according to another embodiment of the present disclosure include a first light-emitting diode that outputs light of a first color, a second light-emitting diode that outputs light of a second color, a third light-emitting diode that outputs light of a third color, a first switching element connected to the anode of the first light-emitting diode, a second switching element connected to the anode of the second light-emitting diode, a third switching element connected to the anode of the third light-emitting diode, a scan switching element connected to the cathode of the first to third light-emitting diodes, and a driving control unit that outputs a scan signal to the scan switching element for a plurality of sub-frame periods and outputs a pulse width variable-based data signal to the first to third switching elements. When a white image is displayed, the driving control unit outputs a first data signal of a first pulse width to the first switching element, outputs a second data signal of a first pulse width to the second switching element, and outputs a third data signal of a second pulse width smaller than the first pulse width to the third switching element.

[0023] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element, output a second data signal of a second level and a first pulse width greater than the first level to a second switching element, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element.

[0024] Meanwhile, the driving control unit can control the second pulse width to be half the first pulse width when displaying a white image.

[0025] Meanwhile, the drive control unit can control the second level to be twice the first level or the second level to be three times the third level.

[0026] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element based on a first clock frequency, output a second data signal of a second level and a first pulse width to a second switching element based on a first clock frequency, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a first clock frequency.

[0027] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element based on a first clock frequency, output a second data signal of a second level and a first pulse width to a second switching element based on a first clock frequency, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a second clock frequency which is greater than the first clock frequency.

[0028] An image display device and a video wall equipped with the same according to one embodiment of the present disclosure include a first light-emitting diode that outputs light of a first color, a second light-emitting diode that outputs light of a second color, a third light-emitting diode that outputs light of a third color, a first switching element connected to the anode of the first light-emitting diode, a second switching element connected to the anode of the second light-emitting diode, a third switching element connected to the anode of the third light-emitting diode, a scan switching element connected to the cathode of the first to third light-emitting diodes, and a driving control unit that outputs a scan signal to the scan switching element for a plurality of sub-frame periods and outputs a pulse width variable-based data signal to the first to third switching elements. The driving control unit outputs a first data signal of a first level to the first switching element, outputs a second data signal of a second level greater than the first level to the second switching element, and outputs a third data signal of a third level smaller than the first level and greater than half of the first level to the third switching element. Accordingly, the color expression capability of the light-emitting diode can be enhanced. In particular, the low-gradation color expression capability of the light-emitting diode can be enhanced. Furthermore, the current efficiency of the light-emitting diode can be increased.

[0029] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element, output a second data signal of a second level and a first pulse width to a second switching element, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element. Accordingly, when displaying a white image, the color expression capability of the light-emitting diode can be increased.

[0030] Meanwhile, the driving control unit can control the second pulse width to be half the first pulse width when displaying a white image. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0031] Meanwhile, the driving control unit can control the second level to be twice the first level or to be three times the third level. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0032] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element based on a first clock frequency, output a second data signal of a second level and a first pulse width to a second switching element based on a first clock frequency, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0033] Meanwhile, when displaying a white image, the driving control unit outputs a first data signal of a first level and a first pulse width to a first switching element based on a first clock frequency, outputs a second data signal of a second level and a first pulse width to a second switching element based on the first clock frequency, and outputs a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a second clock frequency which is higher than the first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0034] Meanwhile, the driving control unit can control the second clock frequency to be twice the first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0035] Meanwhile, the driving control unit can control the level of the current flowing through the third light-emitting diode to reach the first current within the first clock cycle from the turn-on time of the third switching element. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0036] Meanwhile, the driving control unit can set a third level such that, within a first clock cycle from the turn-on time of the third switching element, the level of the current flowing through the third light-emitting diode reaches a first current. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0037] Meanwhile, the driving control unit can control the voltage across the third light-emitting diode to exceed the forward voltage within a first clock cycle from the turn-on time of the third switching element. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0038] Meanwhile, the driving control unit can set a third level such that the voltage across the third light-emitting diode exceeds the forward voltage within a first clock cycle from the turn-on time of the third switching element. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0039] Meanwhile, the driving control unit includes a frequency selector that selects a first clock frequency or a second clock frequency with a frequency greater than the first clock frequency, and outputs a first data signal of a first level and a first pulse width to a first switching element based on the first clock frequency, outputs a second data signal of a second level and a first pulse width based on the first clock frequency to a second switching element, and outputs a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a second clock frequency with a frequency greater than the first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0040] An image display device and a video wall equipped with the same according to another embodiment of the present disclosure include a first light-emitting diode that outputs light of a first color, a second light-emitting diode that outputs light of a second color, a third light-emitting diode that outputs light of a third color, a first switching element connected to the anode of the first light-emitting diode, a second switching element connected to the anode of the second light-emitting diode, a third switching element connected to the anode of the third light-emitting diode, a scan switching element connected to the cathodes of the first to third light-emitting diodes, and a driving control unit that outputs a scan signal to the scan switching element for a plurality of sub-frame periods and outputs a pulse width variable-based data signal to the first to third switching elements. When a white image is displayed, the driving control unit outputs a first data signal of a first pulse width to the first switching element, outputs a second data signal of a first pulse width to the second switching element, and outputs a third data signal of a second pulse width smaller than the first pulse width to the third switching element. Accordingly, the color expression capability of the light-emitting diode can be increased. In particular, it becomes possible to enhance the low-gradation color reproduction capability of the light-emitting diode. Furthermore, it becomes possible to increase the current efficiency of the light-emitting diode.

[0041] Meanwhile, when displaying a white image, the driving control unit outputs a first data signal of a first level and a first pulse width to a first switching element, outputs a second data signal of a second level and a first pulse width greater than the first level to a second switching element, and outputs a third data signal of a third level smaller than the first level and greater than half of the first level and a second pulse width smaller than the first pulse width to a third switching element. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0042] Meanwhile, the driving control unit can control the second pulse width to be half the first pulse width when displaying a white image. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0043] Meanwhile, the driving control unit can control the second level to be twice the first level or to be three times the third level. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0044] Meanwhile, when displaying a white image, the driving control unit can output a first data signal of a first level and a first pulse width to a first switching element based on a first clock frequency, output a second data signal of a second level and a first pulse width to a second switching element based on a first clock frequency, and output a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0045] Meanwhile, when displaying a white image, the driving control unit outputs a first data signal of a first level and a first pulse width to a first switching element based on a first clock frequency, outputs a second data signal of a second level and a first pulse width to a second switching element based on the first clock frequency, and outputs a third data signal of a third level and a second pulse width smaller than the first pulse width to a third switching element based on a second clock frequency which is higher than the first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0046] FIG. 1 is a drawing illustrating a video wall according to one embodiment of the present disclosure.

[0047] Figure 2 is an example of an internal block diagram of the video wall of Figure 1.

[0048] Figure 3 is an example of an internal block diagram of the signal processing device of Figure 2.

[0049] Figure 4 is an internal block diagram of the display of Figure 2.

[0050] FIGS. 5a to 5c are drawings referenced in the description of the light-emitting panel of FIG. 4.

[0051] Figure 6 is a drawing illustrating an example of the light-emitting panel of Figure 4.

[0052] FIGS. 7a to 7d are drawings referenced in the description of the operation of an image display device related to the present disclosure.

[0053] FIG. 8 is a drawing illustrating an example of a light-emitting panel according to one embodiment of the present disclosure.

[0054] FIG. 9 illustrates an example of a scan signal and a data signal applied to a light-emitting diode.

[0055] FIG. 10 illustrates an example of a pixel driving circuit in an image display device according to an embodiment of the present disclosure.

[0056] FIGS. 11 to 18b are drawings referenced in the description of FIG. 10.

[0057] The present disclosure will be described in more detail below with reference to the drawings.

[0058] The suffixes "module" and "part" for components used in the following description are assigned solely for the ease of drafting this specification and do not inherently confer any particularly significant meaning or role. Accordingly, the terms "module" and "part" may be used interchangeably.

[0059] FIG. 1 is a drawing illustrating a video wall according to one embodiment of the present disclosure.

[0060] Referring to the drawings, a video wall (10) according to one embodiment of the present disclosure may include a plurality of image display devices (100a to 100d).

[0061] A video wall (10) according to one embodiment of the present disclosure can receive video from a set-top box (not shown), a server (not shown), or an internal memory, etc.

[0062] For example, the video wall (10) can receive a video signal from a set-top box (not shown) through an HDMI terminal.

[0063] As another example, the video wall (10) can receive a video signal from a server (not shown) through a network terminal.

[0064] Meanwhile, the video wall (10) can be installed inside or outside the building.

[0065] For example, the video wall (10) can be installed in public facilities such as vehicles, terminals, train stations, and airports to provide information such as advertisements, news, and announcements. It can also be placed around show windows in stores such as department stores, shopping malls, and large supermarkets to advertise specific products.

[0066] As another example, the video wall (10) can be installed on a wall inside the house.

[0067] This video wall (10) may be equipped with a plurality of displays (180a to 180d) arranged adjacently.

[0068] Meanwhile, the plurality of displays (180a to 180d) can be implemented as any one of various panels. For example, the plurality of displays (180a to 180d) can be any one of a liquid crystal display panel (LCD panel), a light-emitting panel (OLED panel), an inorganic light-emitting panel (LED panel), etc.

[0069] In this disclosure, the focus is on describing a plurality of displays (180a to 180d) having inorganic light-emitting panels (LED panels).

[0070] Meanwhile, inorganic light-emitting panels (LED panels) contain light-emitting diodes and have the advantage of excellent response speed and color reproduction effects.

[0071] Meanwhile, a plurality of displays (180a to 180d) may be provided with a plurality of panels (210a to 210d) and a bezel (Ba to Bd) surrounding the panels (210a to 210d).

[0072] In the drawing, the video wall (10) is exemplified as having a plurality of image display devices (100a to 100d), each having a display (180a to 180d).

[0073] Alternatively, for displaying images on the video wall (10), signal processing devices (170~170d) provided in each of the plurality of image display devices (100a~100d) may be used.

[0074] For example, an image distributed from a signal processing device (170) is input to a signal processing device (170~170d) provided in each of a plurality of image display devices (100a~100d), and an image processed by each signal processing device (170~170d) is input to each display (180a~180d), and each display (180a~180d) can display the corresponding image.

[0075] Accordingly, the viewer (50) can watch the video displayed on the video wall (10) as shown in the drawing. In particular, the viewer can watch the video displayed on multiple displays (180a to 180d).

[0076] As another example, the video wall (10) may be equipped with a single signal processing device that controls a plurality of image display devices (100a to 100d) in common. Accordingly, the common signal processing device can perform signal processing for the displayed image. Then, the image signal processed is input to each display (180a to 180d), and each display (180a to 180d) can display the corresponding image.

[0077] Meanwhile, when a plurality of displays (180a to 180d) are driven based on a passive matrix method, an inorganic light-emitting panel including a light-emitting diode is driven, the light-emitting diode is made to emit light or not emit light by using a plurality of subframes.

[0078] Figure 2 is an example of an internal block diagram of the video wall of Figure 1.

[0079] Referring to the drawing, the video wall (10) may be equipped with first to fourth image display devices (100a to 100d).

[0080] In the drawings, for convenience, the second to fourth image display devices (100b to 100d) are each shown as having a second to fourth display (180b to 180d) and a second to fourth signal processing device (170b to 170d), but alternatively, they may be equipped with an external device interface unit, a network interface unit, a memory, an image distribution unit, a power supply unit, an audio output unit, etc.

[0081] Meanwhile, the first video display device (100a) may be equipped with an external device interface unit (130), a network interface unit (135), a memory (140), a user input interface unit (150), a signal processing unit (170), a signal processing unit (170), a first display (180a), a power supply unit (190), an audio output unit (185), etc.

[0082] The external device interface unit (130) can transmit and receive data with a connected external device (not shown). To this end, the external device interface unit (130) may include an A / V input / output unit (not shown) or a data input / output unit (not shown).

[0083] For example, the external device interface section (130) may include an HDMI terminal, an RGB terminal, a component terminal, a USB terminal, a micro SD terminal, etc.

[0084] The network interface unit (135) provides an interface for connecting the video display device (100) to a wired / wireless network including the Internet network. For example, the network interface unit (135) can transmit and receive content or data provided by the Internet or a content provider or network operator through the network.

[0085] The memory (140) may store a program for each signal processing and control within the signal processing device (170), and may also store a signal-processed image, voice, or data signal.

[0086] Additionally, the memory (140) may perform the function of temporarily storing video, audio, or data signals input to the external device interface unit (130).

[0087] Meanwhile, a plurality of displays (180a to 180d) may be arranged adjacent to each other and may be equipped with various display panels such as LCD, OLED, and PDP, and may display a predetermined image through the display panels.

[0088] The user input interface unit (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.

[0089] To this end, the user input interface unit (150) may be equipped with a local key including a power key, a touch panel capable of inputting user information, etc.

[0090] The signal processing device (170) can distribute the input image stored in the memory (140), the input image received from an external device through the external device interface unit (130), or the network interface unit (135) into multiple images for display on multiple displays (180a to 180d).

[0091] For example, the signal processing device (170) can crop the input image into multiple images and perform scaling.

[0092] In particular, the signal processing device (170) can perform cropping and scaling, etc., by taking into account the resolution and size of a plurality of displays (180a to 180d).

[0093] Meanwhile, the signal processing device (170) may perform overall control operations of the video wall (10). Specifically, it may control the operation of each unit within the video wall (10).

[0094] Meanwhile, the signal processing device (170) can distribute the image and transmit the distributed image to a plurality of signal processing devices (170 to 170d).

[0095] Meanwhile, at least one signal processing device may be provided to control multiple displays (180a to 180d).

[0096] Meanwhile, in the drawings, to control a plurality of displays (180a to 180d), a plurality of signal processing devices (170 to 170d) corresponding to the number of a plurality of displays (180a to 180d) are illustrated.

[0097] A plurality of signal processing devices (170 to 170d) can each perform a control operation for displaying images on a plurality of displays (180a to 180d).

[0098] A plurality of signal processing devices (170 to 170d) can process an input image signal and transmit the processed image signal to a plurality of displays (180a to 180d), respectively.

[0099] That is, each of the plurality of signal processing devices (170 to 170d) can control the plurality of displays (180a to 180d) to output a predetermined image. Specifically, R, G, and B signals corresponding to the video image to be displayed can be output to the plurality of displays (180a to 180d). Accordingly, the plurality of displays (180a to 180d) can display each image.

[0100] The power supply unit (190) can receive external power or internal power and supply power necessary for the operation of each component.

[0101] The power supply unit (190) supplies power throughout the image display device (100). In particular, it can supply power to a plurality of signal processing devices (170~170d) that can be implemented in the form of a System On Chip (SOC), a plurality of displays (180a~180d) for image display, and an audio output unit (185) for audio output.

[0102] A temperature sensing unit (not shown) can detect the temperature of the video wall (10).

[0103] The temperature detected by the temperature sensing unit (not shown) can be input to at least one of a plurality of signal processing devices (170 to 170d), and at least one of the plurality of signal processing devices (170 to 170d) can control the operation of a fan driving unit (not shown) to reduce internal heat based on the detected temperature.

[0104] Meanwhile, an image display device (100A) according to one embodiment of the present disclosure may include an image receiving unit (105), a memory (140), a user input interface unit (150), a sensor unit (not shown), a signal processing unit (170), a display (180), and an audio output unit (185).

[0105] The video receiving unit (105) may include a tuner unit (110), a demodulator unit (120), a network interface unit (130), and an external device interface unit (130).

[0106] Meanwhile, the video receiving unit (105), unlike the drawing, may include only the tuner unit (110), the demodulation unit (120), and the external device interface unit (130). That is, it may not include the network interface unit (130).

[0107] The tuner unit (110) selects an RF (Radio Frequency) broadcast signal corresponding to a channel selected by the user or all previously stored channels among the RF broadcast signals received through an antenna (not shown). Additionally, it converts the selected RF broadcast signal into an intermediate frequency signal or a baseband video or audio signal.

[0108] For example, if the selected RF broadcast signal is a digital broadcast signal, it is converted into a digital IF signal (DIF), and if it is an analog broadcast signal, it is converted into an analog baseband video or audio signal (CVBS / SIF). That is, the tuner unit (110) can process a digital broadcast signal or an analog broadcast signal. The analog baseband video or audio signal (CVBS / SIF) output from the tuner unit (110) can be directly input to a signal processing device (170).

[0109] Meanwhile, the tuner unit (110) may be equipped with multiple tuners to receive multiple channels of broadcast signals. Alternatively, a single tuner that simultaneously receives multiple channels of broadcast signals is also possible.

[0110] The demodulator (120) receives the digital IF signal (DIF) converted by the tuner (110) and performs a demodulation operation.

[0111] The demodulation unit (120) can output a stream signal (TS) after performing demodulation and channel decoding. At this time, the stream signal may be a signal in which a video signal, an audio signal, or a data signal is multiplexed.

[0112] The stream signal output from the demodulation unit (120) can be input to the signal processing unit (170). The signal processing unit (170) performs demultiplexing, video / audio signal processing, etc., then outputs video to the display (180) and outputs audio to the audio output unit (185).

[0113] The external device interface unit (130) can transmit or receive data with a connected external device (not shown), for example, a set-top box (50). To this end, the external device interface unit (130) may include an A / V input / output unit (not shown).

[0114] The external device interface section (130) can be connected wirelessly or via wired connection to external devices such as a DVD (Digital Versatile Disk), Blu-ray, game console, camera, camcorder, computer (laptop), set-top box, etc., and can also perform input / output operations with the external devices.

[0115] The A / V input / output unit can receive video and audio signals from an external device. Meanwhile, the wireless communication unit (not shown) can perform short-range wireless communication with other electronic devices.

[0116] Through such a wireless communication unit (not shown), the external device interface unit (130) can exchange data with an adjacent mobile terminal (600). In particular, the external device interface unit (130) can receive device information, information on an application being executed, an application image, etc. from the mobile terminal (600) in mirroring mode.

[0117] The network interface unit (135) provides an interface for connecting the video display device (100) to a wired / wireless network including the Internet network. For example, the network interface unit (135) can receive content or data provided by the Internet or a content provider or network operator through the network.

[0118] Meanwhile, the network interface section (135) may include a wireless communication section (not shown).

[0119] The memory (140) may store a program for each signal processing and control within the signal processing device (170), and may also store a signal-processed image, voice, or data signal.

[0120] Additionally, the memory (140) may perform the function of temporarily storing video, audio, or data signals input to the external device interface unit (130). Additionally, the memory (140) may store information regarding a predetermined broadcast channel through a channel memory function such as a channel map.

[0121] Although the memory (140) of FIG. 2 is illustrated in an embodiment in which it 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 within the signal processing device (170).

[0122] The user input interface unit (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.

[0123] For example, user input signals such as power on / off, channel selection, and screen settings can be transmitted / received from a remote control device (200), user input signals input from local keys (not shown) such as a power key, channel key, volume key, and setting value can be transmitted to a signal processing device (170), user input signals input from a sensor unit (not shown) that senses a user's gesture can be transmitted to a signal processing device (170), or signals from the signal processing device (170) can be transmitted to a sensor unit (not shown).

[0124] The signal processing device (170) can demultiplex a stream input through the tuner unit (110), the demodulator unit (120), the network interface unit (135), or the external device interface unit (130), or process the demultiplexed signals to generate and output a signal for video or audio output.

[0125] For example, the signal processing device (170) can receive a broadcast signal or an HDMI signal, etc., received from the video receiving unit (105), perform signal processing based on the received broadcast signal or HDMI signal, and output a signal-processed video signal.

[0126] The image signal processed by the signal processing device (170) can be input to the display (180) and displayed as an image corresponding to the image signal. Additionally, the image signal processed by the signal processing device (170) can be input to an external output device through the external device interface unit (130).

[0127] The voice signal processed by the signal processing device (170) can be sound-outputted to the audio output unit (185). Additionally, the voice signal processed by the signal processing device (170) can be input to an external output device through the external device interface unit (130).

[0128] Although not illustrated in FIG. 2, the signal processing device (170) may include a demultiplexer, an image processing unit, etc. That is, the signal processing device (170) can perform various signal processing and, accordingly, can be implemented in the form of a System On Chip (SOC). This will be described later with reference to FIG. 3.

[0129] In addition, the signal processing device (170) can control the overall operation within the image display device (100). For example, the signal processing device (170) can control the tuner unit (110) to control the selection (tuning) of an RF broadcast corresponding to a channel selected by the user or a pre-stored channel.

[0130] Additionally, the signal processing device (170) can control the image display device (100) by means of a user command or internal program input through the user input interface unit (150).

[0131] Meanwhile, the signal processing device (170) can control the display (180) to display an image. At this time, the image displayed on the display (180) may be a still image or a video, and may be a 2D image or a 3D image.

[0132] Meanwhile, the signal processing device (170) can cause a predetermined object to be displayed within the image displayed on the display (180). For example, the object may be at least one of a connected web screen (newspaper, magazine, etc.), an EPG (Electronic Program Guide), various menus, widgets, icons, still images, videos, and text.

[0133] Meanwhile, the signal processing device (170) can recognize the user's location based on an image captured by a shooting unit (not shown). For example, it can determine the distance (z-axis coordinate) between the user and the image display device (100). In addition, it can determine the x-axis coordinate and y-axis coordinate within the display (180) corresponding to the user's location.

[0134] The display (180) generates a driving signal by converting a video signal, data signal, OSD signal, control signal processed by a signal processing device (170) or a video signal, data signal, control signal, etc. received from an external device interface unit (130).

[0135] Meanwhile, the display (180) can be configured as a touch screen and used as an input device in addition to an output device.

[0136] The audio output unit (185) receives a voice-processed signal from the signal processing unit (170) and outputs it as voice.

[0137] The shooting unit (not shown) photographs the user. The shooting unit (not shown) can be implemented with one camera, but is not limited thereto, and can also be implemented with multiple cameras. The image information captured by the shooting unit (not shown) can be input to the signal processing device (170).

[0138] The signal processing device (170) can detect a user's gesture based on each or a combination of an image captured from a shooting unit (not shown) or a signal detected from a sensor unit (not shown).

[0139] The power supply unit (190) supplies power throughout the image display device (100). In particular, the power supply unit (190) can supply power to a signal processing device (170) that can be implemented in the form of a System On Chip (SOC), a display (180) for image display, and an audio output unit (185) for audio output.

[0140] Specifically, the power supply unit (190) may be equipped with a converter that converts AC power into DC power and a DC / DC converter that converts the level of DC power.

[0141] The remote control device (200) transmits user input to the user input interface unit (150). To this end, the remote control device (200) may use Bluetooth, RF (Radio Frequency) communication, infrared (IR) communication, UWB (Ultra Wideband), ZigBee, etc. Additionally, the remote control device (200) may receive video, audio, or data signals output from the user input interface unit (150) and display or output audio from the remote control device (200).

[0142] Meanwhile, the above-described video display device (100) may be a digital broadcast receiver capable of receiving fixed or mobile digital broadcasts.

[0143] Meanwhile, the block diagram of the image display device (100) illustrated in FIG. 3 is a block diagram for an embodiment of the present disclosure. Each component of the block diagram may be integrated, added, or omitted according to the specifications of the image display device (100) actually implemented. That is, as needed, two or more components may be combined into one component, or one component may be subdivided into two or more components. Furthermore, the functions performed in each block are intended to explain the embodiments of the present disclosure, and the specific operations or devices thereof do not limit the scope of the rights of the present disclosure.

[0144] Figure 3 is an example of an internal block diagram of the signal processing device of Figure 2.

[0145] Referring to the drawings, a signal processing device (170) according to one embodiment of the present disclosure may include a demultiplexer (310), an image processing unit (320), a processor (330), and an audio processing unit (370). Additionally, it may further include a data processing unit (not shown).

[0146] The demultiplexer (310) demultiplexes the input stream. For example, if an MPEG-2 TS is input, it can be demultiplexed to separate it into video, audio, and data signals. Here, the stream signal input to the demultiplexer (310) may be a stream signal output from the tuner (110), the demodulator (120), or the external device interface (130).

[0147] The image processing unit (320) can perform signal processing on the input image. For example, the image processing unit (320) can perform image processing on the image signal demultiplexed from the demultiplexing unit (310).

[0148] To this end, the image processing unit (320) may include an image decoder (325), a scaler (335), an image quality processing unit (635), an image encoder (not shown), an OSD processing unit (340), a frame image rate conversion unit (350), and a formatter (360), etc.

[0149] The video decoder (325) decodes the demultiplexed video signal, and the scaler (335) performs scaling so that the resolution of the decoded video signal can be output on the display (180).

[0150] The image decoder (325) may be equipped with decoders of various specifications. For example, it may be equipped with MPEG-2, H,264 decoders, 3D image decoders for color images and depth images, decoders for multiple viewpoint images, etc.

[0151] The scaler (335) can scale the input video signal, which has been decoded in the video decoder (325), etc.

[0152] For example, the scaler (335) can upscale when the size or resolution of the input video signal is small, and downscale when the size or resolution of the input video signal is large.

[0153] The image quality processing unit (635) can perform image quality processing on the input image signal, which has been decoded in the image decoder (325), etc.

[0154] For example, the image processing unit (635) can perform noise removal processing of the input image signal, expand the resolution of the grayscale of the input image signal, perform image resolution enhancement, perform high dynamic range (HDR) based signal processing, vary the frame image rate, and perform image processing corresponding to panel characteristics, particularly the light-emitting panel.

[0155] The OSD processing unit (340) generates an OSD signal based on user input or independently. For example, based on a user input signal, it can generate a signal to display various information as graphics or text on the screen of the display (180). The generated OSD signal may include various data such as user interface screens, various menu screens, widgets, and icons of the image display device (100). Additionally, the generated OSD signal may include 2D objects or 3D objects.

[0156] Additionally, the OSD processing unit (340) can generate a pointer that can be displayed on a display based on a pointing signal input from the remote control device (200). In particular, such a pointer can be generated by a pointing control unit, and the OSD processing unit (240) may include such a pointing control unit (not shown). Of course, it is also possible for the pointing control unit (not shown) to be provided separately rather than being provided within the OSD processing unit (240).

[0157] The frame rate converter (FRC) (350) can convert the frame rate of the input video. Meanwhile, the frame rate converter (350) can also output the video as is without converting the frame rate.

[0158] Meanwhile, the formatter (360) can convert the format of the input video signal into a video signal for display on a display and output it.

[0159] In particular, the formatter (360) can change the format of the video signal to correspond to the display panel.

[0160] The processor (330) can control the overall operation within the image display device (100) or the signal processing device (170).

[0161] For example, the processor (330) can control the tuner (110) to select (Tuning) an RF broadcast corresponding to a channel selected by the user or a pre-stored channel.

[0162] Additionally, the processor (330) can control the image display device (100) by means of a user command or an internal program input through the user input interface unit (150).

[0163] Additionally, the processor (330) can perform data transmission control with the network interface unit (135) or the external device interface unit (130).

[0164] Additionally, the processor (330) can control the operation of the demultiplexer (310), image processing unit (320), etc., within the signal processing device (170).

[0165] Meanwhile, the audio processing unit (370) within the signal processing device (170) can perform voice processing of the demultiplexed voice signal. To this end, the audio processing unit (370) may be equipped with various decoders.

[0166] Additionally, the audio processing unit (370) within the signal processing device (170) can process bass, treble, volume control, etc.

[0167] A data processing unit (not shown) within a signal processing device (170) can perform data processing of a demultiplexed data signal. For example, if the demultiplexed data signal is an encoded data signal, it can be decoded. The encoded data signal may be Electronic Program Guide information containing broadcast information such as the start time and end time of a broadcast program aired on each channel.

[0168] Meanwhile, the block diagram of the signal processing device (170) illustrated in FIG. 4 is a block diagram for an embodiment of the present disclosure. Each component of the block diagram may be integrated, added, or omitted according to the specifications of the signal processing device (170) actually implemented.

[0169] In particular, the frame video rate converter (350) and the formatter (360) may be provided separately from the video processing unit (320).

[0170] Figure 4 is an internal block diagram of the display of Figure 2.

[0171] Referring to the drawing, the light-emitting panel-based display (180) may include a light-emitting panel (210), a first interface unit (230), a second interface unit (231), a timing controller (232), a scan driving unit (234), a data driving unit (236), a memory (240), a power supply unit (290), etc.

[0172] The display (180) receives a video signal (Vd), a first DC power supply (V1), and a second DC power supply (V2), and can display a predetermined image based on the video signal (Vd).

[0173] Meanwhile, the first interface unit (230) within the display (180) can receive a video signal (Vd) and a first DC power supply (V1) from the signal processing device (170).

[0174] Here, the first DC power supply (V1) can be used for the operation of the power supply unit (290) and the timing controller (232) within the display (180).

[0175] Next, the second interface unit (231) can receive a second DC power supply (V2) from an external power supply unit (190). Meanwhile, the second DC power supply (V2) can be input to a data driving unit (236) within the display (180).

[0176] The timing controller (232) can output a data driving signal (Sda) and a scan driving signal (Sga) based on the video signal (Vd).

[0177] For example, when the first interface unit (230) converts an input video signal (Vd) and outputs a converted video signal (va1), the timing controller (232) can output a data driving signal (Sda) and a scan driving signal (Sga) based on the converted video signal (va1).

[0178] The timing controller (232) can receive additional signals, such as a control signal and a vertical synchronization signal (Vsync), in addition to the video signal (Vd) from the signal processing device (170).

[0179] In addition, the timing controller (232) can output a scan drive signal (Sga) for the operation of the scan drive unit (234) and a data drive signal (Sda) for the operation of the data drive unit (236) based on a control signal, a vertical synchronization signal (Vsync), etc., in addition to the video signal (Vd).

[0180] The data driving signal (Sda) at this time may be a data driving signal for driving RGB subpixels when the panel (210) has RGB subpixels.

[0181] Meanwhile, the timing controller (232) can further output a control signal (Cs) to the scan drive unit (234).

[0182] The scan driving unit (234) and the data driving unit (236) supply a scan signal and a data signal to the light-emitting panel (210) through the scan line (GL) and the data line (DL), respectively, according to the scan driving signal (Sga) and the data driving signal (Sda) from the timing controller (232). Accordingly, the light-emitting panel (210) displays a predetermined image.

[0183] Meanwhile, the light-emitting panel (210) may include a light-emitting layer, and to display an image, a plurality of scan lines (GL) and data lines (DL) may be arranged in an intersecting matrix form at each pixel corresponding to the light-emitting layer.

[0184] Meanwhile, the data driving unit (236) can output a data signal to the light-emitting panel (210) based on the second DC power supply (V2) from the second interface unit (231).

[0185] The power supply unit (290) can supply various power sources to the scan drive unit (234), data drive unit (236), timing controller (232), etc.

[0186] Meanwhile, the timing controller (232), scan driver (234), and data driver (236) in the drawing can be implemented as a single integrated circuit (IC).

[0187] Accordingly, the timing controller (232), scan drive unit (234), and data drive unit (236) can be named as a drive control unit (285).

[0188] Meanwhile, the drive control unit (285) may include a buffer (238) that stores frame data.

[0189] In particular, the timing controller (232) within the drive control unit (285) can output a gate signal and a data signal for image display based on frame data stored in the buffer (238).

[0190] FIGS. 5a to 5c are drawings referenced in the description of the light-emitting panel of FIG. 4.

[0191] First, FIG. 5a is a drawing showing a pixel within a light-emitting panel (210).

[0192] Referring to the drawing, the light-emitting panel (210) may have a plurality of scan lines (Scan 1 to Scan n) and a plurality of data lines (R1, G1, B1 to Rm, Gm, Bm) that intersect therewith.

[0193] Meanwhile, a pixel (subpixel) is defined in the intersection area of ​​the scan line and the data line within the light-emitting panel (210). In the drawing, a pixel having RGB subpixels (SR1, SG1, SB1) is shown.

[0194] Meanwhile, a red light-emitting diode, a green light-emitting diode, and a blue light-emitting diode are placed in the RGB subpixels (SR1, SG1, SB1), respectively.

[0195] FIG. 5b illustrates the circuit of one subpixel within a pixel of the light-emitting panel of FIG. 5a.

[0196] Referring to the drawing, the light-emitting subpixel circuit (CRTm) is of the passive type and can be equipped with only a light-emitting diode (LED) without a separate switching element.

[0197] As shown in the drawing, the anode of the light-emitting diode (LED) is connected to a data line so that a data signal (Vdata) can be input, and the cathode of the light-emitting diode (LED) is connected to a scan line so that a scan signal (Vscan) can be input.

[0198] Meanwhile, a light-emitting diode can emit light or not emit light based on a plurality of subframes based on a passive matrix method.

[0199] Figure 5c is a diagram showing examples of scan signals and data signals.

[0200] Referring to the drawing, the scan signal (Vscan) applied to each of the red light-emitting diode, green light-emitting diode, and blue light-emitting diode maintains the LVb level and then drops to the LVa level at the scan timing.

[0201] At this time, the width of the scan signal (Vscan) can be set to Wa.

[0202] Meanwhile, red light-emitting diodes may have higher luminous efficiency than green light-emitting diodes and blue light-emitting diodes due to their device characteristics.

[0203] In response to this, the driving control unit (285) can control the level of the data signal supplied to the red light-emitting diode so that it is lower than the level of the data signal supplied to the green light-emitting diode or the blue light-emitting diode.

[0204] Figure 5c (b) illustrates a data signal (Vdata) that maintains the level of LVd and then rises to the LVc level in response to the scan timing of the scan signal (Vscan).

[0205] Figure 5c (c) illustrates a data signal (Vdatam) that maintains the level of LVd and then rises to a level higher than LVc, LVe, in response to the scan timing of the scan signal (Vscan).

[0206] A data signal (Vdata) of the LVc level can be applied to a red light-emitting diode, and a data signal (Vdatam) of the LVe level, which is higher than the LVc level, is preferably applied to a green light-emitting diode or a blue light-emitting diode.

[0207] Accordingly, it is possible to output a data signal corresponding to the light-emitting diode, and furthermore, to achieve uniform color realization.

[0208] Meanwhile, the data signal (Vdata) of Fig. 5c (b) or the data signal (Vdatam) of Fig. 5c (c) is a pulse width variable-based data signal, and the brightness of the light-emitting diode is varied by varying the duty cycle corresponding to the pulse width.

[0209] Figure 6 is a drawing illustrating an example of the light-emitting panel of Figure 4.

[0210] Referring to the drawing, the light-emitting panel (210) may have a plurality of data lines and a plurality of scan lines.

[0211] In FIG. 6, for convenience of explanation, four data lines (Data 1 to Data 4) and four scan lines (Scan 1 to Scan 4) are exemplified as an example of a light-emitting panel (210).

[0212] FIGS. 7a to 7d are drawings referenced in the description of the operation of an image display device related to the present disclosure.

[0213] FIG. 7a illustrates an example of a data signal applied in correspondence with the case where the frame gradation is the first gradation during a plurality of sub-frame periods within a frame period.

[0214] Referring to the drawing, multiple subframe periods (Subframe 1 to 3) may be provided within a frame period (Frame 1).

[0215] For convenience of explanation, the drawing shows three subframe periods (Subframe 1 to 3) within a frame period (Frame 1), but various variations are possible.

[0216] Figure 7a (a) illustrates that during the first subframe (Subframe 1) period among a plurality of subframes (Subframe 1 to 3), data signals (Vdata 1 to 4) are applied to each of the four data lines shown in Figure 6.

[0217] In the drawing, data signals (Vdata 1 to 4) having four pulses or voltages (V) each on four data lines are exemplified during the period of the first subframe (Subframe 1).

[0218] At this time, the pulse width of the data signal (Vdata 1~4) can be Wx.

[0219] Figure 7a (b) illustrates that scan signals (Vscan 1 to 4) are sequentially applied to each of the four scan lines during the period of the first subframe (Subframe 1).

[0220] Accordingly, during the first subframe (Subframe 1) period, 16 light-emitting diodes emit light as shown in (c) of FIG. 7a.

[0221] Figure 7a (a) illustrates that during the period of the second subframe (Subframe 2), data signals (Vdata 1 to 4) are applied to each of the four data lines shown in Figure 6.

[0222] In the drawing, data signals (Vdata 1 to 4) having one pulse or voltage (V) on each of the four data lines during the period of the second subframe (Subframe 2) are exemplified.

[0223] Figure 7a (b) illustrates that scan signals (Vscan 1 to 4) are sequentially applied to each of the four scan lines during the period of the second subframe (Subframe 2).

[0224] Accordingly, during the second subframe period, four light-emitting diodes in the diagonal direction emit light, as shown in (c) of FIG. 7a.

[0225] Figure 7a (a) illustrates that during the third subframe period, data signals (Vdata 1 to 4) are applied to each of the four data lines shown in Figure 6.

[0226] In the drawing, data signals (Vdata 1 to 4) having one pulse or voltage (V) on each of the four data lines during the period of the third subframe (Subframe 3) are exemplified.

[0227] Figure 7a (b) illustrates that scan signals (Vscan 1 to 4) are sequentially applied to each of the four scan lines during the period of the third subframe (Subframe 3).

[0228] Accordingly, during the third subframe period, four light-emitting diodes in a diagonal direction emit light, as shown in (c) of FIG. 7a.

[0229]

[0230] FIG. 7b illustrates an example of a data signal applied in response to a case where the frame gradation is a second gradation lower than the first gradation during a plurality of sub-frame periods within a frame period.

[0231] Figure 7b (a) illustrates that during the first subframe (Subframe 1) period among a plurality of subframes (Subframe 1 to 3), data signals (Vdata 1 to 4) are applied to each of the four data lines shown in Figure 6.

[0232] In the drawing, data signals (Vdata 1 to 4) having four pulses or voltages (V) each on four data lines are exemplified during the period of the first subframe (Subframe 1).

[0233] At this time, the pulse width of the data signal (Vdata 1~4) can be Wx.

[0234] Figure 7b (b) illustrates that scan signals (Vscan 1 to 4) are sequentially applied to each of the four scan lines during a period of multiple subframes (Subframe 1 to 3).

[0235] Accordingly, during the first subframe (Subframe 1) period, 16 light-emitting diodes emit light as shown in (c) of Fig. 7b.

[0236] Meanwhile, FIG. 7b(a) illustrates that during the second subframe (Subframe 2) period among the multiple subframes (Subframe 1 to 3), data signals (Vdata 1 to 4) each having one pulse or voltage (V) are applied to the four data lines shown in FIG. 6, and during the third subframe (Subframe 3) period, no pulse or voltage (V) is applied.

[0237] Accordingly, during the second subframe (Subframe 2) period, four light-emitting diodes in the diagonal direction light up as shown in (c) of FIG. 7b, and during the third subframe (Subframe 3) period, all 16 light-emitting diodes are turned off and do not light up.

[0238] FIG. 7c illustrates an example of a data signal applied in response to a case where the frame gradation is a third gradation lower than the second gradation during a plurality of sub-frame periods within a frame period.

[0239] FIG. 7c(a) illustrates that during the first subframe (Subframe 1) period of a plurality of subframes (Subframe 1 to 3), data signals (Vdata 1 to 4) each having one pulse or voltage (V) are applied to the four data lines shown in FIG. 6, and during the second subframe (Subframe 2) period and the third subframe (Subframe 3) period, no pulse or voltage (V) is applied.

[0240] Figure 7c (b) illustrates that scan signals (Vscan 1 to 4) are sequentially applied to each of the four scan lines during a period of multiple subframes (Subframe 1 to 3).

[0241] Accordingly, during the first subframe (Subframe 1) period, four light-emitting diodes in the diagonal direction light up as shown in (c) of FIG. 7c, and during the second subframe (Subframe 2) period and the third subframe (Subframe 3) period, all 16 light-emitting diodes are turned off and do not light up.

[0242] FIG. 8 is a drawing illustrating an example of a light-emitting panel according to one embodiment of the present disclosure.

[0243] Referring to the drawings, a light-emitting panel (210) according to one embodiment of the present disclosure has a plurality of driving control units (285a to 285h).

[0244] In the drawings, drive control units (285a~285h) arranged in an n*4 configuration are exemplified, but are not limited thereto and various variations are possible.

[0245] Meanwhile, each driving control unit (285a~285h) outputs a scan signal to a plurality of light-emitting diodes for each of the plurality of sub-frame periods and outputs a data signal for image display.

[0246] For example, each drive control unit (285a to 285h) can output a data signal based on pulse width modulation (PWM) based on a constant current source.

[0247] FIG. 9 illustrates an example of a scan signal and a data signal applied to a light-emitting diode.

[0248] Referring to the drawing, a scan signal (SC) and a data signal (DT) applied to a light-emitting diode (LED) based on a clock signal (GCLK) can be output.

[0249] The data signal (DT) may be a data signal based on pulse width modulation (PWM) based on a constant current source.

[0250] Meanwhile, the scan signal (SC) has a high level and a low level, and the scan switching element can be turned on in response to the low level.

[0251] Meanwhile, the data signal (DT) has a high level and a low level, and the data switching element can be turned on in response to the low level.

[0252] FIG. 10 illustrates an example of a pixel driving circuit in an image display device according to an embodiment of the present disclosure.

[0253] Referring to the drawings, a pixel driving circuit (1400) in an image display device (100) according to an embodiment of the present disclosure comprises: a first light-emitting diode (LEDR) that outputs light of a first color; a second light-emitting diode (LEDG) that outputs light of a second color; a third light-emitting diode (LEDB) that outputs light of a third color; a first switching element (SWDR) connected to the anode of the first light-emitting diode (LEDR); a second switching element (SWDG) connected to the anode of the second light-emitting diode (LEDG); a third switching element (SWDB) connected to the anode of the third light-emitting diode (LEDB); a scan switching element (SWCa) connected to the cathodes of the first to third light-emitting diodes (LEDR~LEDB); and a driving circuit that outputs a scan signal (Vscan) to the scan switching element (SWCa) for a plurality of sub-frame periods and outputs a pulse width variable-based data signal to the first to third switching elements (SWDB). It includes a control unit (285).

[0254] In the drawing, a first light-emitting diode (LEDR), a second light-emitting diode (LEDG), and a third light-emitting diode (LEDB) are arranged in a first scan line (SCAN1), and a first scan switching element ((SWCa) connected to the cathodes of the first to third light-emitting diodes (LEDR~LEDB) in the first scan line (SCAN1) is illustrated.

[0255] Meanwhile, a first light-emitting diode (LEDR), a second light-emitting diode (LEDG), and a third light-emitting diode (LEDB) are arranged in a second scan line (SCAN2), and a second scan switching element (SWCb) can be connected to the cathodes of the first to third light-emitting diodes (LEDR~LEDB) in the second scan line (SCAN2).

[0256] Meanwhile, a first light-emitting diode (LEDR), a second light-emitting diode (LEDG), and a third light-emitting diode (LEDB) are arranged in a third scan line (SCAN3), and a third scan switching element (SWCc) can be connected to the cathodes of the first to third light-emitting diodes (LEDR~LEDB) in the third scan line (SCAN3).

[0257] Meanwhile, the driving control unit (285) outputs a first data signal of a first level (3LV in FIG. 14) to a first switching element (SWDR), outputs a second data signal of a second level (6LV in FIG. 14) which is larger than the first level (3LV) to a second switching element (SWDG), and outputs a third data signal of a third level (2LV in FIG. 14) which is smaller than the first level (3LV) and larger than half of the first level (3LV) to a third switching element (SWDB). Accordingly, the color expression capability of the light-emitting diode can be increased. In particular, the color expression capability of the light-emitting diode in low gradations can be increased. Furthermore, the current efficiency of the light-emitting diode can be increased.

[0258] Meanwhile, the first light-emitting diode (LEDR), the second light-emitting diode (LEDG), and the third light-emitting diode (LEDB) may be a red light-emitting diode (LEDR), a green light-emitting diode (LEDG), and a blue light-emitting diode (LEDB), respectively, which output red light, green light, and blue light.

[0259] Meanwhile, the pixel driving circuit (1400) according to an embodiment of the present disclosure may further include a fourth switching element (SWBR, SWBG, SWBB) connected to the anode of each light-emitting diode (LEDR, LEDG, LEDB) and supplying each buffer current based on a switching operation.

[0260] For example, the driving control unit (285) can control to output a first level voltage to the red light-emitting diode (LEDR), output a second level voltage higher than the first level to the green light-emitting diode (LEDG), and output a third level voltage higher than the second level to the blue light-emitting diode (LEDB) during the precharge period prior to the display period.

[0261] That is, different levels of pre-charge voltage (Vpre) can be supplied to the anodes of each light-emitting diode (LEDR, LEDG, LEDB) based on the turn-on of each fourth switching element (SWBR, SWBG, SWBB).

[0262] Meanwhile, the pixel driving circuit (1400) according to an embodiment of the present disclosure may further include a current source (ICHR, ICHG, ICHB) connected to each data switching element (SWDR, SWWDG, SWDB) and outputting current to each data switching element (SWDR, SWWDG, SWDB).

[0263] Meanwhile, the pixel driving circuit (1400) according to an embodiment of the present disclosure may further include a discharge switching element (SWDISR, SWDISG, SWDISB) disposed between the anode and ground terminal (GND) of each light-emitting diode (LEDR, LEDG, LEDB).

[0264] For example, the driving control unit (285) can turn on each discharge switching element (SWDISR, SWDISG, SWDISB) during the discharge period after the display period, and control the voltage of the anode of each light-emitting diode (LEDR, LEDG, LEDB) to be discharged quickly.

[0265] FIGS. 11 to 18b are drawings referenced in the description of FIG. 10.

[0266] Figure 11 is a diagram showing the efficiency of each light-emitting diode relative to the current.

[0267] Referring to the drawing, the horizontal axis represents the current level, and the vertical axis can represent the luminous efficiency of the light-emitting diode.

[0268] GRr represents the efficiency curve relative to the current level of a red light-emitting diode (LEDR), GRg represents the efficiency curve relative to the current level of a green light-emitting diode (LEDG), and GRb represents the efficiency curve relative to the current level of a blue light-emitting diode (LEDB).

[0269] For example, it is desirable to apply a data signal of the same pulse width to output a white image or white light through a red light emitting diode (LEDR), a green light emitting diode (LEDG), and a blue light emitting diode (LEDB).

[0270] Meanwhile, to output a white image or white light through a red light emitting diode (LEDR), a green light emitting diode (LEDG), and a blue light emitting diode (LEDB), the levels of each data signal may be in a ratio of approximately 3:6:1.

[0271] Meanwhile, corresponding to a ratio of 3:6:1, if a point for the current ratio in each graph (GRr, Gg, Grb) of FIG. 11 is selected, it can be selected as a point such as Pr, Pg, Pb1.

[0272] At this time, the current level at point Pr may be 0.75mA, the current level at point Pg may be 1.75mA, and the current level at point Pb1 may be 0.25mA.

[0273] That is, the current ratio at points Pr, Pg, and Pb1 can correspond to a ratio of approximately 3:6:1.

[0274] However, the efficiencies at points Pr, Pg, and Pb1 are 0.83, 0.96, and 0.7, respectively.

[0275] In particular, there is a problem in that the efficiency of blue light-emitting diodes (LEDB) is significantly lower than that of other red light-emitting diodes (LEDR) and green light-emitting diodes (LEDG).

[0276] Accordingly, in this disclosure, in order to solve the problem of reduced efficiency of a blue light-emitting diode (LEDB), the point Pb2 is selected instead of the point Pb1 on the GRb graph.

[0277] Meanwhile, the current level at point Pb2 can be 0.5mA. According to this, the efficiency of the blue light emitting diode (LEDB) increases from 0.7 to approximately 0.9.

[0278] However, the current ratio at the points Pr, Pg, and Pb2 may be approximately 3:6:2, rather than approximately 3:6:1.

[0279] FIG. 12a illustrates a white image or white light display in which the levels of the data signals of the red light emitting diode (LEDR), the green light emitting diode (LEDG), and the blue light emitting diode (LEDB) are in a ratio of approximately 3:6:1.

[0280] Referring to the drawing, when the levels of the data signals of the red light emitting diode (LEDR), green light emitting diode (LEDG), and blue light emitting diode (LEDB) are in a ratio of approximately 3:6:1 and the pulse widths are equal to Na, the ratio of the pulse widths of the data signals is 1:1:1, so a white image or white light can be displayed.

[0281] FIG. 12b illustrates a pink image or pink light display in which the levels of the data signals of the red light emitting diode (LEDR), the green light emitting diode (LEDG), and the blue light emitting diode (LEDB) are in a ratio of approximately 3:6:1.

[0282] Referring to the drawing, when the levels of the data signals of the red light emitting diode (LEDR), green light emitting diode (LEDG), and blue light emitting diode (LEDB) are in a ratio of approximately 3:6:1, the pulse width ratio of each data signal is Na:Nb:Nb, and when the ratio of Na:Nb is 10:8, the pulse width ratio of each data signal is 5:5:5, so that a pink image or pink light can be displayed.

[0283] FIG. 12c is an example of an internal block diagram of a drive control unit related to the present disclosure.

[0284] Referring to the drawings, the driving control unit (285x) related to the present disclosure may include a PWM length calculation unit (1212, 1214, 1216) for a red light emitting diode (LEDR), a green light emitting diode (LEDG), and a blue light emitting diode (LEDB), a counter (1220) that operates based on a clock signal, and a comparator (1230, 1232, 1234) that compares the output signal of the counter (1220) with the output signal of each PWM length calculation unit (1212, 1214, 1216).

[0285] That is, the driving control unit (285x) related to the present disclosure can output a data signal of variable pulse width through comparators (1230, 1232, 1234).

[0286] Meanwhile, as shown in FIG. 12a or FIG. 12b, if the levels of the data signals of the red light emitting diode (LEDR), green light emitting diode (LEDG), and blue light emitting diode (LEDB) are set in a ratio of approximately 3:6:1, there is a problem that the efficiency of the blue light emitting diode (LEDB) is significantly lower than the efficiency of the other red light emitting diode (LEDR) and green light emitting diode (LEDG).

[0287] In addition, there is a disadvantage that the level of the data signal of the blue light emitting diode (LEDB) or the level of the current flowing through the blue light emitting diode (LEDB) is low, so it takes a considerable amount of time to reach the forward voltage for the operation of the blue light emitting diode (LEDB).

[0288] In particular, there is a disadvantage in that it is difficult to maintain white balance using blue light-emitting diodes (LEDBs) at low gradations.

[0289] Accordingly, in order to solve these disadvantages, the present disclosure increases the level of the data signal of the blue light-emitting diode (LEDB) among the levels of the data signals of the red light-emitting diode (LEDR), the green light-emitting diode (LEDG), and the blue light-emitting diode (LEDB). This is described with reference to FIG. 13a, etc.

[0290] FIG. 13a is an example of an internal block diagram of a drive control unit according to an embodiment of the present disclosure.

[0291] Referring to the drawings, a driving control unit (285mA) according to an embodiment of the present disclosure may comprise a PWM length calculation unit (1212, 1214, 1216) for a red light emitting diode (LEDR), a green light emitting diode (LEDG), and a blue light emitting diode (LEDB); a weighting unit (1222, 1224, 1226) that adds weights to the output signals of each PWM length calculation unit (1212, 1214, 1216); a counter (1220) that operates based on a clock signal; and a comparator (1230, 1232, 1234) that compares the output signal of the counter (1220) with the output signal of each weighting unit (1222, 1224, 1226).

[0292] That is, the driving control unit (285mA) according to the embodiment of the present disclosure can output a data signal of variable pulse width through comparators (1230, 1232, 1234).

[0293] For example, the first comparator (1230) in the drive control unit (285mA) can output a first data signal for a red light emitting diode (LEDR), and the second comparator (1232) can output a second data signal for a green light emitting diode (LEDG) and a third data signal for a blue light emitting diode (LEDB).

[0294] FIG. 13b is another example of an internal block diagram of a drive control unit according to an embodiment of the present disclosure.

[0295] Referring to the drawings, a driving control unit (285mb) according to an embodiment of the present disclosure may include a frequency selector (1205) for selecting a first clock frequency or a second clock frequency that has a frequency greater than that of the first clock frequency.

[0296] For example, the frequency selector (1205) can output a first clock signal and a second clock signal based on a first clock frequency, and output a third clock signal based on a second clock frequency that has a higher frequency than the first clock frequency.

[0297] As another example, the frequency selector (1205) may select two or more clock frequencies and output first to third clock signals based on each different clock frequency.

[0298] Meanwhile, the driving control unit (285mb) according to the embodiment of the present disclosure may include a frequency selector (1205), a PWM length calculation unit (1212, 1214, 1216) for a red light emitting diode (LEDR), a green light emitting diode (LEDG), and a blue light emitting diode (LEDB), a counter (1223, 1225, 1227) that operates based on a first to third clock signal output from the frequency selector (1205), and a comparator (1230, 1232, 1234) that compares the output signal of each counter (1223, 1225, 1227) with the output signal of each PWM length calculation unit (1212, 1214, 1216).

[0299] That is, the driving control unit (285mb) according to the embodiment of the present disclosure can output a data signal of variable pulse width through comparators (1230, 1232, 1234).

[0300] For example, the first comparator (1230) in the drive control unit (285mb) can output a first data signal for a red light emitting diode (LEDR), and the second comparator (1232) can output a second data signal for a green light emitting diode (LEDG) and a third data signal for a blue light emitting diode (LEDB).

[0301] FIG. 14 is an example of a plurality of data signals based on a first clock frequency.

[0302] Referring to the drawings, a driving control unit (285) according to one embodiment of the present disclosure outputs a first data signal of a first level (3LV) to a first switching element (SWDR), outputs a second data signal of a second level (6LV) greater than the first level (3LV) to a second switching element (SWDG), and outputs a third data signal of a third level (2LV) smaller than the first level (3LV) and greater than half of the first level (3LV) to a third switching element (SWDB).

[0303] As shown in the drawing, the drive control unit (285) can control the second level (6LV) to be twice the first level (3LV) or to be three times the third level (2LV).

[0304] Meanwhile, the first data signal of the first level (3LV) can be input to a red light emitting diode (LEDR), the second data signal of the second level (6LV) can be input to a green light emitting diode (LEDG), and the third data signal of the third level (2LV) can be input to a blue light emitting diode (LEDB).

[0305] According to the levels of each data signal in FIG. 14, unlike FIG. 12a, the level of the third data signal input to the blue light emitting diode (LEDB) is doubled, so that the input to both ends of the blue light emitting diode (LEDB) can quickly exceed the forward voltage (Vf). Accordingly, the color expression capability of the light emitting diode can be increased.

[0306] Meanwhile, since the level of the third data signal input to the blue light emitting diode (LEDB) is doubled, it is desirable for the pulse width of the third data signal to be reduced when displaying a white image.

[0307] That is, when displaying a white image, the driving control unit (285) can output a first data signal of a first level (3LV) and a first pulse width (Nm) to a first switching element (SWDR), output a second data signal of a second level (6LV) and a first pulse width (Nm) to a second switching element (SWDG), and output a third data signal of a third level (2LV) and a second pulse width (Nn) smaller than the first pulse width (Nm) to a third switching element (SWDB). Accordingly, when displaying a white image, the color expression capability of the light-emitting diode can be increased.

[0308] Meanwhile, the driving control unit (285) can control the second pulse width (Nn) to be half the first pulse width (Nm) when displaying a white image.

[0309] In the drawing, the first pulse width (Nm) corresponds to 20 times the clock period of the first clock signal based on the first clock frequency, and the second pulse width (Nn) corresponds to 10 times the clock period of the first clock signal based on the first clock frequency.

[0310] That is, according to FIG. 14, the driving control unit (285) can output a first data signal of a first level (3LV) and a first pulse width (Nm) to a first switching element (SWDR) based on a first clock frequency when displaying a white image, output a second data signal of a second level (6LV) and a first pulse width (Nm) to a second switching element (SWDG) based on a first clock frequency, and output a third data signal of a third level (2LV) and a second pulse width (Nn) smaller than the first pulse width (Nm) to a third switching element (SWDB) based on a first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0311] Meanwhile, referring to FIG. 14, a driving control unit (285) in an image display device (100) according to another embodiment of the present disclosure outputs a first data signal of a first pulse width (Nm) to a first switching element (SWDR) when displaying a white image, outputs a second data signal of a first pulse width (Nm) to a second switching element (SWDG), and outputs a third data signal of a second pulse width (Nn) smaller than the first pulse width (Nm) to a third switching element (SWDB). Accordingly, the color expression capability of the light-emitting diode can be increased. In particular, the color expression capability of the light-emitting diode in low gradations can be increased. Furthermore, the current efficiency of the light-emitting diode can be increased.

[0312] FIG. 15 is an example of a plurality of data signals based on a first clock frequency and a second clock frequency.

[0313] Referring to the drawings, a driving control unit (285) according to one embodiment of the present disclosure outputs a first data signal of a first level (3LV) to a first switching element (SWDR), outputs a second data signal of a second level (6LV) greater than the first level (3LV) to a second switching element (SWDG), and outputs a third data signal of a third level (2LV) smaller than the first level (3LV) and greater than half of the first level (3LV) to a third switching element (SWDB).

[0314] As shown in the drawing, the drive control unit (285) can control the second level (6LV) to be twice the first level (3LV) or to be three times the third level (2LV).

[0315] Meanwhile, the first data signal of the first level (3LV) can be input to a red light emitting diode (LEDR), the second data signal of the second level (6LV) can be input to a green light emitting diode (LEDG), and the third data signal of the third level (2LV) can be input to a blue light emitting diode (LEDB).

[0316] According to the levels of each data signal in FIG. 15, unlike FIG. 12a, the level of the third data signal input to the blue light emitting diode (LEDB) is doubled, so that the input to both ends of the blue light emitting diode (LEDB) can quickly exceed the forward voltage (Vf). Accordingly, the color expression capability of the light emitting diode can be increased.

[0317] Meanwhile, since the level of the third data signal input to the blue light emitting diode (LEDB) is doubled, it is desirable for the pulse width of the third data signal to be reduced when displaying a white image.

[0318] That is, when displaying a white image, the driving control unit (285) can output a first data signal of a first level (3LV) and a first pulse width (Np) to a first switching element (SWDR), output a second data signal of a second level (6LV) and a first pulse width (Np) to a second switching element (SWDG), and output a third data signal of a third level (2LV) and a second pulse width (Nr) smaller than the first pulse width (Np) to a third switching element (SWDB). Accordingly, when displaying a white image, the color expression capability of the light-emitting diode can be increased.

[0319] Meanwhile, the driving control unit (285) can control the second pulse width (Nr) to be half the first pulse width (Np) when displaying a white image.

[0320] In the drawing, the first pulse width (Np) corresponds to 10 times the clock period of a first clock signal based on a first clock frequency, and the second pulse width (Nr) corresponds to 10 times the clock period of a second clock signal based on a second clock frequency that has a frequency greater than the first clock frequency.

[0321] Meanwhile, the clock period of the first clock signal may be twice the clock period of the second clock signal.

[0322] That is, according to FIG. 15, the driving control unit (285) can output a first data signal of a first level (3LV) and a first pulse width (Np) to a first switching element (SWDR) based on a first clock frequency when displaying a white image, output a second data signal of a second level (6LV) and a first pulse width (Np) to a second switching element (SWDG) based on a first clock frequency, and output a third data signal of a third level (2LV) and a second pulse width (Nr) smaller than the first pulse width (Np) to a third switching element (SWDB) based on a second clock frequency that is greater than the first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased when displaying a white image.

[0323] Meanwhile, the driving control unit (285) can control the second clock frequency to be twice the first clock frequency. Accordingly, the color expression capability of the light-emitting diode can be increased.

[0324] Meanwhile, referring to FIG. 15, a driving control unit (285) in an image display device (100) according to another embodiment of the present disclosure outputs a first data signal of a first pulse width (Np) to a first switching element (SWDR) when a white image is displayed, outputs a second data signal of a first pulse width (Np) to a second switching element (SWDG), and outputs a third data signal of a second pulse width (Nr) smaller than the first pulse width (Np) to a third switching element (SWDB). Accordingly, the color expression capability of the light-emitting diode can be increased. In particular, the color expression capability of the light-emitting diode in low gradations can be increased. Furthermore, the current efficiency of the light-emitting diode can be increased.

[0325] FIG. 16 illustrates sequential driving by scan line within a plurality of sub-frame periods.

[0326] Referring to the drawing, the frame time may be from T1 to T9, and multiple subframe times may be allocated within the frame time.

[0327] Among the multiple subframe times, the first subframe time (1st SF) may correspond to periods T2 to T5, and the second subframe time (2nd SF) may correspond to periods T5 to T8.

[0328] During the period T2 to T3 of the first subframe period (1st SF), a light-emitting diode corresponding to the first scan line among a plurality of light-emitting diodes can emit light.

[0329] During the period T3 to T4 of the first subframe period (1st SF), a light-emitting diode corresponding to the second scan line among a plurality of light-emitting diodes can emit light.

[0330] Meanwhile, during the period T4 to T5 of the first subframe period (1st SF), the light-emitting diode corresponding to the last scan line among the plurality of light-emitting diodes can emit light.

[0331] During the period T5 to T6 of the second subframe period (2nd SF), a light-emitting diode corresponding to the first scan line among a plurality of light-emitting diodes can emit light.

[0332] During the period T6 to T7 of the second subframe period (2nd SF), the light-emitting diode corresponding to the second scan line among the plurality of light-emitting diodes can emit light.

[0333] Meanwhile, during the period T7 to T8 of the second subframe period (2nd SF), the light-emitting diode corresponding to the last scan line among the plurality of light-emitting diodes can emit light.

[0334] Meanwhile, the duration of multiple subframes can be 64.

[0335] For example, to maintain the ratio of R, G, and B at 1:1:1 when displaying a bright white image, the driving control unit (285) can output data signals corresponding to 100 clock cycles to the red light emitting diode (LEDR), green light emitting diode (LEDG), and blue light emitting diode (LEDB), respectively.

[0336] As another example, when displaying a dark yellow image, in order to maintain the ratio of R, G, and B at 1:1:0, the driving control unit (285) can output data signals corresponding to two clock cycles to the red light emitting diode (LEDR) and the green light emitting diode (LEDG), respectively.

[0337] As another example, to maintain the ratio of R, G, and B at 5:4:4 when displaying a bright pink image, the driving control unit (285) can output a data signal corresponding to 100 clock cycles to a red light emitting diode (LEDR) and output a data signal corresponding to 80 clock cycles to a green light emitting diode (LEDG) and a blue light emitting diode (LEDB), respectively.

[0338] FIG. 17a is a drawing illustrating data signals, etc. related to the present disclosure.

[0339] Referring to the drawings, the data signal (SSWDx) associated with the present disclosure may be a data signal corresponding to a blue light emitting diode (LEDB).

[0340] In the drawings, the pulse width of the data signal (SSWDx) related to the present disclosure is exemplified as being from To to Tx14.

[0341] Meanwhile, the level of the current (ICHx) output from the current source (ICHB) for the blue light emitting diode (LEDB) may be LVx.

[0342] Meanwhile, based on the data signal (SSWDx) and the current (ICHx) output from the current source (ICHB), the voltage (VDx) across the blue light-emitting diode (LEDB) rises sequentially starting from To and exceeds the forward voltage (Vf) after time Tx4.

[0343] Meanwhile, based on the data signal (SSWDx) and the current (ICHx) output from the current source (ICHB), the current (IDx) flowing through the blue light emitting diode (LEDB) increases after time Tx4 and maintains the LVy level after time Tx5.

[0344] According to the data signal (SSWDx) related to the present disclosure of FIG. 17a, the pulse width is 14 times the clock period, but since the level of the current source (ICHB) is low at LVx, the voltage (VDx) across the blue light emitting diode (LEDB) exceeds the forward voltage (Vf) from the 5th clock period, and consequently, the blue light emitting diode (LEDB) emits light from the 5th clock period.

[0345] This time delay may be primarily caused by parasitic coffee-saturns of the blue light-emitting diode (LEDB) or a low current level output from the current source (ICHB).

[0346] Accordingly, in this disclosure, to resolve the light emission delay of the blue light-emitting diode (LEDB) of FIG. 17a, the level of the current output from the current source (ICHB) is increased. It is increased to a level approximately twice that of LVx.

[0347] FIG. 17b is a dorm illustrating a data signal, etc., according to an embodiment of the present disclosure.

[0348] Referring to the drawings, the data signal (SSWD) according to an embodiment of the present disclosure may be a data signal corresponding to a blue light emitting diode (LEDB).

[0349] In the drawings, the pulse width of the data signal (SSWD) according to an embodiment of the present disclosure is illustrated as being To to Ta7.

[0350] Meanwhile, the level of the current (ICH) output from the current source (ICHB) for the blue light emitting diode (LEDB) can be LVn, which is greater than LVx. LVn can be approximately twice LVx.

[0351] Meanwhile, based on the data signal (SSWD) and the current (ICH) output from the current source (ICHB), it is desirable that the voltage (VD) across the blue light-emitting diode (LEDB) rises at To and exceeds the forward voltage (Vf) before time Ta1.

[0352] Meanwhile, based on the data signal (SSWD) and the current (ICH) output from the current source (ICHB), the current (ID) flowing through the blue light emitting diode (LEDB) rises at T0 and can maintain an LVp level greater than the LVy level before time Ta1.

[0353] Meanwhile, the driving control unit (285) can control the level of the current flowing through the third light-emitting diode (LEDB) to reach the first current (LVp) within the first clock cycle (Ta1) from the turn-on time (To) of the third switching element (SWDB). Accordingly, the color expression capability of the light-emitting diode can be increased.

[0354] Meanwhile, the driving control unit (285) can set a third level (2LV) such that the level of the current (ID) flowing through the third light-emitting diode (LEDB) reaches the first current (LVp) within the first clock cycle (Ta1) from the turn-on time (To) of the third switching element (SWDB). Accordingly, the color expression capability of the light-emitting diode can be increased.

[0355] Meanwhile, the driving control unit (285) can control the voltage across the third light-emitting diode (LEDB) (VD) to exceed the forward voltage (Vf) within the first clock cycle (Ta1) from the turn-on time (To) of the third switching element (SWDB). Accordingly, the color expression capability of the light-emitting diode can be increased.

[0356] Meanwhile, the driving control unit (285) can set a third level (2LV) such that the voltage across the third light-emitting diode (LEDB) exceeds the forward voltage (Vf) within the first clock cycle (Ta1) from the turn-on time (To) of the third switching element (SWDB). Accordingly, the color expression capability of the light-emitting diode can be increased.

[0357] According to the data signal (SSWD) according to the embodiment of the present disclosure of FIG. 17b, the pulse width is seven times the clock period, and since the level of the current source (ICHB) is LVn which is approximately twice as high as LVx, the forward voltage (Vf) is exceeded within one clock period, as in the waveform of the voltage (VD) across the blue light emitting diode (LEDB), and consequently, the blue light emitting diode (LEDB) emits light starting from within one clock period.

[0358] Accordingly, time delay during the emission of the blue light-emitting diode (LEDB) does not occur, and the color expression capability of the blue light-emitting diode (LEDB) can be increased. Furthermore, the color expression capability in low gradations can be increased, and white balance can be increased.

[0359] Fig. 18a illustrates color expression capabilities in low gradation.

[0360] Referring to the drawing, the accumulated current in each red light emitting diode (LEDR), green light emitting diode (LEDG), and blue light emitting diode (LEDB) may be 42, 84, and 14 mA, respectively, in case 1; 22, 84, and 9 mA, respectively, in case 2; and 22, 84, and 13 mA, respectively, in case 3.

[0361] Case 1 may be an ideal case, Case 2 may be a case related to the present disclosure as shown in FIG. 17a, and Case 3 may be a case according to an embodiment of the present disclosure as shown in FIG. 17b.

[0362] Compared to case 1, the cumulative current error rate in the blue light emitting diode (LEDB) in case 2 is low at 64%, but compared to case 1, the cumulative current error rate in the blue light emitting diode (LEDB) in case 3 can be much higher than 64% at 92%.

[0363] Accordingly, the color rendering capability of the blue light-emitting diode (LEDB) can be significantly improved in case 3 compared to case 2. In other words, the color rendering capability in low gradations can be increased.

[0364] Fig. 18b illustrates color expression capabilities in high tones.

[0365] Referring to the drawing, the accumulated current in each red light emitting diode (LEDR), green light emitting diode (LEDG), and blue light emitting diode (LEDB) may be 600, 1200, and 200 mA, respectively, in case 1; 600, 1200, and 195 mA, respectively, in case 2; and 600, 1200, and 199 mA, respectively, in case 3.

[0366] Case 1 may be an ideal case, Case 2 may be a case related to the present disclosure as shown in FIG. 17a, and Case 3 may be a case according to an embodiment of the present disclosure as shown in FIG. 17b.

[0367] Compared to case 1, the cumulative current error rate of the blue light emitting diode (LEDB) in case 2 is 97%, and compared to case 1, the cumulative current error rate of the blue light emitting diode (LEDB) in case 3 can be 99%. In other words, at high gradation, the difference in color expression capability between cases is not significant.

[0368] Although preferred embodiments of the present disclosure have been illustrated and described above, the present disclosure is not limited to the specific embodiments described above. Various modifications are possible by those skilled in the art without departing from the essence of the present disclosure as claimed in the claims, and such modifications should not be understood individually from the technical spirit or perspective of the present disclosure.

Claims

1. A first light-emitting diode that outputs light of a first color; A second light-emitting diode that outputs light of a second color; A third light-emitting diode that outputs light of a third color; A first switching element connected to the anode of the first light-emitting diode; A second switching element connected to the anode of the second light-emitting diode; A third switching element connected to the anode of the third light-emitting diode; A scan switching element connected to the cathode of the first to third light-emitting diodes; A driving control unit that outputs a scan signal to the scan switching element according to a plurality of sub-frame periods and outputs a pulse width variable-based data signal to the first to third switching elements; The above drive control unit is, A first data signal of a first level is output to the first switching element, and The second data signal of a second level greater than the first level is output to the second switching element, and An image display device that outputs a third data signal of a third level, which is smaller than the first level and larger than half of the first level, to the third switching element.

2. In Paragraph 1, The above drive control unit is, When displaying a white image, The first data signal of the first level and first pulse width is output to the first switching element, and The second data signal of the second level and the first pulse width is output to the second switching element, and An image display device that outputs a third data signal having a third level and a second pulse width smaller than the first pulse width to the third switching element.

3. In Paragraph 2, The above drive control unit is, An image display device that controls the second pulse width to be half the first pulse width when displaying the white image above.

4. In Paragraph 1, The above drive control unit is, An image display device that controls the second level to be twice the first level or the second level to be three times the third level.

5. In Paragraph 1, The above drive control unit is, When displaying a white image, Based on the first clock frequency, the first data signal of the first level and first pulse width is output to the first switching element, and Based on the first clock frequency, the second data signal of the second level and the first pulse width is output to the second switching element, and An image display device that outputs a third data signal of a second pulse width smaller than the first pulse width to the third switching element based on the first clock frequency.

6. In Paragraph 1, The above drive control unit is, When displaying a white image, Based on the first clock frequency, the first data signal of the first level and first pulse width is output to the first switching element, and Based on the first clock frequency, the second data signal of the second level and the first pulse width is output to the second switching element, and An image display device that outputs a third data signal with a second pulse width smaller than the first pulse width to the third switching element based on a second clock frequency with a frequency greater than the first clock frequency.

7. In Paragraph 6, The above drive control unit is, An image display device that controls the second clock frequency to be twice the first clock frequency.

8. In Paragraph 1, The above drive control unit is, An image display device that controls the level of the current flowing through the third light-emitting diode to reach a first current within a first clock cycle from the turn-on time of the third switching element.

9. In Paragraph 1, The above drive control unit is, An image display device that sets the third level such that, within a first clock cycle from the turn-on time of the third switching element, the level of the current flowing through the third light-emitting diode reaches the first current.

10. In Paragraph 1, The above drive control unit is, An image display device that controls the voltage across the third light-emitting diode to exceed the forward voltage within a first clock cycle from the turn-on time of the third switching element.

11. In Paragraph 1, The above drive control unit is, An image display device that sets the third level such that, within a first clock cycle from the turn-on time of the third switching element, the voltage across the third light-emitting diode exceeds the forward voltage.

12. In Paragraph 6, The above drive control unit is, A frequency selector for selecting a first clock frequency or a second clock frequency having a frequency greater than that of the first clock frequency; Based on the first clock frequency, the first data signal of the first level and first pulse width is output to the first switching element, and Based on the first clock frequency, the second data signal of the second level and the first pulse width is output to the second switching element, and An image display device that outputs a third data signal with a second pulse width smaller than the first pulse width to the third switching element based on a second clock frequency with a frequency greater than the first clock frequency.

13. A first light-emitting diode that outputs light of a first color; A second light-emitting diode that outputs light of a second color; A third light-emitting diode that outputs light of a third color; A first switching element connected to the anode of the first light-emitting diode; A second switching element connected to the anode of the second light-emitting diode; A third switching element connected to the anode of the third light-emitting diode; A scan switching element connected to the cathode of the first to third light-emitting diodes; A driving control unit that outputs a scan signal to the scan switching element according to a plurality of sub-frame periods and outputs a pulse width variable-based data signal to the first to third switching elements; The above drive control unit, when displaying a white image, A first data signal of a first pulse width is output to the first switching element, and The second data signal of the first pulse width is output to the second switching element, and An image display device that outputs a third data signal with a second pulse width smaller than the first pulse width to the third switching element.

14. In Paragraph 13, The above drive control unit, when displaying the white image, The first data signal of the first level and first pulse width is output to the first switching element, and Outputting the second data signal of the first pulse width, which is a second level greater than the first level, to the second switching element, and An image display device that outputs a third data signal to a third switching element, the third level being smaller than the first level and larger than half of the first level, and the second pulse width being smaller than the first pulse width.

15. In Paragraph 13, The above drive control unit is, An image display device that controls the second pulse width to be half the first pulse width when displaying the white image above.

16. In Paragraph 14, The above drive control unit is, An image display device that controls the second level to be twice the first level or the second level to be three times the third level.

17. In Paragraph 14, The above drive control unit is, When displaying the white image above, Based on the first clock frequency, the first data signal of the first level and first pulse width is output to the first switching element, and Based on the first clock frequency, the second data signal of the second level and the first pulse width is output to the second switching element, and An image display device that outputs a third data signal of a second pulse width smaller than the first pulse width to the third switching element based on the first clock frequency.

18. In Paragraph 13, The above drive control unit is, When displaying a white image, Based on the first clock frequency, the first data signal of the first level and first pulse width is output to the first switching element, and Based on the first clock frequency, the second data signal of the second level and the first pulse width is output to the second switching element, and An image display device that outputs a third data signal with a second pulse width smaller than the first pulse width to the third switching element based on a second clock frequency with a frequency greater than the first clock frequency.

19. Includes a plurality of image display devices; and The above image display device is, A video wall comprising a video display device according to any one of paragraphs 1 through 18.

Images