Display device and operating method thereof

Abstract

A display device according to an embodiment of the present disclosure may comprise: an image reception unit for receiving an image; a first panel including a plurality of pixels and displaying the image received by the image reception unit through the plurality of pixels; a second panel disposed on one surface of the first panel and controlled such that light selectively passes through an area of the first panel; and a controller which acquires image information of the image displayed on the first panel and controls the transmittance of the second panel on the basis of the acquired image information.

Description

Display device and method of operation thereof

[0001] The present disclosure relates to a display device, and more particularly, to a transparent display device.

[0002] Digital TV services utilizing wired or wireless networks are becoming more widespread. Digital TV services can offer a variety of services not available with existing analog broadcasting services.

[0003] For example, IPTV (Internet Protocol Television), a type of digital TV service, and smart TV services offer interactivity, allowing users to actively choose the type of program they want to watch and when. Building on this interactivity, IPTV and smart TV services can also offer a variety of additional services, such as internet search, home shopping, and online games.

[0004] Recent display devices feature transparent displays, allowing images to be displayed transparently while exposing the background behind the transparent display. Furthermore, display devices may incorporate a physical light shield on the back of the transparent display to block light entering from the rear.

[0005] However, conventional physical shading screens have the form of a roll screen, and can only shade the entire area extending in the long direction of the transparent display as the shading screen moves, and cannot shade only a portion of the area.

[0006] Accordingly, in the case of a high-luminance area or a fixed area displayed in the same position for a certain period of time, such as a logo, the light from the high-luminance area or the fixed area cannot be locally blocked by the light shield.

[0007] This causes problems in that afterimage prevention cannot be effectively achieved and power consumption cannot be reduced.

[0008] An object of the present disclosure may be to provide a light blocking function in conjunction with an image displayed on a transparent display device.

[0009] An object of the present disclosure may be to prevent afterimages while maintaining the image quality of a fixed image displayed on a transparent display device.

[0010] An object of the present disclosure may be to control the transmittance of a high-luminance area displayed on a transparent display device and reduce power consumption by lowering the luminance.

[0011] A display device according to an embodiment of the present disclosure may include an image receiving unit that receives an image, a first panel that includes a plurality of pixels and displays the image received by the image receiving unit through the plurality of pixels, a second panel that is arranged on one surface of the first panel and is controlled so that an area of ​​the first panel selectively transmits light, and a controller that obtains image information of the image displayed on the first panel and controls the transmittance of the second panel based on the obtained image information.

[0012] A method of operating a display device, comprising: an image receiving unit for receiving an image according to an embodiment of the present disclosure; a first panel including a plurality of pixels and displaying the image received by the image receiving unit through the plurality of pixels; and a second panel disposed on one surface of the first panel and having an area of ​​the first panel controlled to selectively transmit light; may include a step of obtaining image information of the image displayed on the first panel; and a step of controlling the transmittance of the second panel based on the obtained image information.

[0013] According to embodiments of the present disclosure, the afterimage prevention effect can be improved while maintaining the image quality of a fixed image displayed on a transparent display device. Furthermore, power consumption can be reduced as the luminance of the fixed image is reduced.

[0014] According to an embodiment of the present disclosure, the difference in contrast between a main object and a background object can be maximized.

[0015] According to an embodiment of the present disclosure, the contrast ratio with the remaining areas can be improved by reducing the transmittance of the maximum brightness area and the minimum brightness area.

[0016] FIG. 1 is a block diagram illustrating the configuration of a display device according to one embodiment of the present invention.

[0017] FIG. 2 is a drawing illustrating an electronic shading method according to another embodiment of the present disclosure.

[0018] FIGS. 3A and 3B are drawings illustrating various forms of a display according to an embodiment of the present disclosure.

[0019] FIG. 4 is a flowchart for explaining an operating method of a display device according to an embodiment of the present disclosure.

[0020] FIGS. 5 to 6B are drawings illustrating a process for preventing afterimages caused by a fixed image displayed on a first panel according to an embodiment of the present disclosure.

[0021] FIG. 7 is a drawing explaining the relationship between transmittance and luminance according to an embodiment of the present disclosure.

[0022] FIG. 8 is a drawing illustrating a method for preventing afterimages when displaying a menu or information displayed at a fixed location on a first panel according to one embodiment of the present disclosure.

[0023] FIG. 9 is a flowchart illustrating a method of operating a display device according to another embodiment of the present disclosure.

[0024] FIG. 10 is a flowchart illustrating a method of operating a display device according to another embodiment of the present disclosure.

[0025] FIG. 11 is a drawing illustrating an example of reducing the transmittance of a maximum brightness area and a minimum brightness area of ​​an image according to an embodiment of the present disclosure.

[0026] FIGS. 12 and 13 are flowcharts illustrating a process of controlling at least one of a first panel or a second panel based on front brightness and back brightness of a display device according to an embodiment of the present disclosure.

[0027] FIG. 14 is a drawing illustrating an embodiment of adjusting the transmittance or brightness of a bright image area of ​​an HDR image according to the surrounding brightness when an HDR image is input according to an embodiment of the present disclosure.

[0028] FIG. 15 is a drawing illustrating a configuration of a display device according to another embodiment of the present disclosure.

[0029] Hereinafter, embodiments related to the present invention will be described in more detail with reference to the drawings. The suffixes "module" and "part" used in the following description for components are assigned or used interchangeably solely for the convenience of writing the specification, and do not in themselves have distinct meanings or roles.

[0030] A display device according to an embodiment of the present invention is, for example, an intelligent display device that adds computer-assisted functionality to its broadcast reception function. While faithfully performing the broadcast reception function, it can also be equipped with Internet functionality and other features, providing a more user-friendly interface, such as a manual input device, touch screen, or space remote control. Furthermore, with support for wired or wireless Internet functionality, it can connect to the Internet and a computer, enabling functions such as email, web browsing, banking, or gaming. A standardized, general-purpose operating system can be used for these various functions.

[0031] Accordingly, the display device described in the present invention can perform various user-friendly functions, for example, by allowing various applications to be freely added or deleted on a general-purpose operating system kernel. More specifically, the display device can be a network TV, HBB TV, smart TV, LED TV, OLED TV, etc., and in some cases, it can also be applied to smartphones.

[0032] FIG. 1 is a block diagram illustrating the configuration of a display device according to one embodiment of the present invention.

[0033] Referring to FIG. 1, the display device (100) may include an image receiving unit (130), an external device interface (135), a memory (140), a user input interface (150), a controller (170), a wireless communication interface (173), a display (180), a speaker (185), and a power supply circuit (190).

[0034] The video receiver (130) may include a tuner (131), a demodulator (132), and a network interface (133).

[0035] The tuner (131) can select a specific broadcast channel according to a channel selection command. The tuner (131) can receive a broadcast signal for the selected specific broadcast channel.

[0036] The demodulator (132) can separate the received broadcast signal into a video signal, an audio signal, and a data signal related to the broadcast program, and can restore the separated video signal, audio signal, and data signal into a form that can be output.

[0037] The external device interface (135) can receive an application or a list of applications within an adjacent external device and transmit it to the controller (170) or memory (140).

[0038] The external device interface (135) can provide a connection path between the display device (100) and the external device. The external device interface (135) can receive one or more of images and audio output from an external device connected wirelessly or wiredly to the display device (100) and transmit them to the controller (170). The external device interface (135) can include a plurality of external input terminals. The plurality of external input terminals can include an RGB terminal, one or more HDMI (High Definition Multimedia Interface) terminals, and a component terminal.

[0039] A video signal of an external device input through an external device interface (135) can be output through a display (180). A voice signal of an external device input through an external device interface (135) can be output through a speaker (185).

[0040] An external device that can be connected to the external device interface (135) may be any one of a set-top box, a Blu-ray player, a DVD player, a game console, a sound bar, a smartphone, a PC, a USB memory, and a home theater, but this is only an example.

[0041] The network interface (133) may provide an interface for connecting the display device (100) to a wired / wireless network including the Internet. The network interface (133) may transmit or receive data to or from other users or other electronic devices via the connected network or another network linked to the connected network.

[0042] Additionally, some content data stored in the display device (100) can be transmitted to a selected user or electronic device among other users or other electronic devices pre-registered in the display device (100).

[0043] The network interface (133) can access a predetermined web page through a connected network or another network linked to the connected network. That is, by accessing a predetermined web page through a network, data can be transmitted or received with the corresponding server.

[0044] In addition, the network interface (133) can receive content or data provided by a content provider or network operator. That is, the network interface (133) can receive content such as movies, advertisements, games, VOD, broadcast signals, etc. and information related thereto provided from a content provider or network provider via a network.

[0045] Additionally, the network interface (133) can receive firmware update information and update files provided by the network operator, and can transmit data to the Internet or content provider or network operator.

[0046] The network interface (133) can select and receive a desired application from among applications open to the public via a network.

[0047] The memory (140) stores a program for each signal processing and control within the controller (170), and can store signal-processed image, voice, or data signals.

[0048] In addition, the memory (140) may perform a function for temporary storage of video, audio, or data signals input from an external device interface (135) or a network interface (133), and may store information about a specific image through a channel memory function.

[0049] The memory (140) can store an application or a list of applications input from an external device interface (135) or a network interface (133).

[0050] The display device (100) can play content files (video files, still image files, music files, document files, application files, etc.) stored in the memory (140) and provide them to the user.

[0051] The user input interface (150) can transmit a signal input by the user to the controller (170) or transmit a signal from the controller (170) to the user. For example, the user input interface (150) can receive and process control signals such as power on / off, channel selection, and screen setting from the remote control device (200) according to various communication methods such as Bluetooth, Ultra Wideband (WB), ZigBee, Radio Frequency (RF) communication, or infrared (IR) communication, or process control signals from the controller (170) to be transmitted to the remote control device (200).

[0052] In addition, the user input interface (150) can transmit control signals input from local keys (not shown) such as a power key, channel key, volume key, and setting value to the controller (170).

[0053] An image signal processed by the controller (170) can be input to the display (180) and displayed as an image corresponding to the image signal. In addition, an image signal processed by the controller (170) can be input to an external output device through an external device interface (135).

[0054] The voice signal processed by the controller (170) can be output as audio to the speaker (185). In addition, the voice signal processed by the controller (170) can be input to an external output device through the external device interface (135).

[0055] In addition, the controller (170) can control the overall operation within the display device (100).

[0056] In addition, the controller (170) can control the display device (100) by a user command or internal program input through the user input interface (150), and can connect to a network to enable the user to download a desired application or application list into the display device (100).

[0057] The controller (170) enables the user-selected channel information, etc. to be output through a display (180) or speaker (185) together with processed video or audio signals.

[0058] In addition, the controller (170) allows a video signal or audio signal from an external device, for example, a camera or camcorder, input through the external device interface (135) to be output through the display (180) or speaker (185) in accordance with an external device video playback command received through the user input interface (150).

[0059] Meanwhile, the controller (170) can control the display (180) to display an image, for example, a broadcast image input through a tuner (131), an external input image input through an external device interface (135), an image input through a network interface, or an image stored in a memory (140) can be controlled to be displayed on the display (180). In this case, the image displayed on the display (180) can be a still image or a moving image, and can be a 2D image or a 3D image.

[0060] In addition, the controller (170) can control the playback of content stored in the display device (100), received broadcast content, or external input content input from outside, and the content can be in various forms such as broadcast video, external input video, audio file, still image, connected web screen, and document file.

[0061] The wireless communication interface (173) can communicate with an external device through wired or wireless communication. The wireless communication interface (173) can perform short-range communication with the external device. To this end, the wireless communication interface (173) can support short-range communication using at least one of Bluetooth™, RFID (Radio Frequency Identification), Infrared Data Association (IrDA), UWB (Ultra Wideband), ZigBee, NFC (Near Field Communication), Wi-Fi (Wireless-Fidelity), Wi-Fi Direct, and Wireless USB (Wireless Universal Serial Bus) technologies. This wireless communication interface (173) can support wireless communication between the display device (100) and a wireless communication system, between the display device (100) and another display device (100), or between the display device (100) and a network in which the display device (100, or an external server) is located via a short-range wireless communication network (Wireless Area Network). The short-range wireless communication network can be a short-range wireless personal area network (Wireless Personal Area Network).

[0062] Here, the other display device (100) may be a wearable device (e.g., a smartwatch, smart glasses, a head-mounted display (HMD)) or a mobile terminal such as a smart phone that can exchange data with (or be linked to) the display device (100) according to the present invention. The wireless communication interface (173) may detect (or recognize) a wearable device capable of communication around the display device (100).

[0063] Furthermore, if the detected wearable device is a device certified to communicate with the display device (100) according to the present invention, the controller (170) can transmit at least a portion of the data processed in the display device (100) to the wearable device via the wireless communication interface (173). Accordingly, a user of the wearable device can utilize the data processed in the display device (100) via the wearable device.

[0064] The display (180) can generate a driving signal by converting a video signal, data signal, OSD signal processed by the controller (170) or a video signal, data signal, etc. received from an external device interface (135) into R, G, and B signals, respectively.

[0065] Meanwhile, since the display device (100) illustrated in FIG. 1 is merely an embodiment of the present invention, some of the illustrated components may be integrated, added, or omitted depending on the specifications of the display device (100) actually implemented.

[0066] That is, two or more components may be combined into a single component, or a single component may be subdivided into two or more components, as needed. Furthermore, the functions performed by each block are intended to illustrate embodiments of the present invention, and their specific operations or devices do not limit the scope of the present invention.

[0067] According to another embodiment of the present invention, the display device (100) may receive and play back an image through a network interface (133) or an external device interface (135) without having a tuner (131) and a demodulator (132), unlike that shown in FIG. 1.

[0068] For example, the display device (100) may be implemented separately as an image processing device, such as a set-top box, for receiving broadcast signals or contents according to various network services, and a content playback device for playing contents input from the image processing device.

[0069] In this case, the operating method of the display device according to the embodiment of the present invention to be described below may be performed by any one of the display device (100) described with reference to FIG. 1, as well as an image processing device such as the separated set-top box, or a content playback device having a display (180) and a speaker (185).

[0070] FIG. 2 is a drawing illustrating an electronic shading method according to another embodiment of the present disclosure.

[0071] The display device (100) may further include a light-shielding panel (210) arranged on one side of the display (180). The light-shielding panel (210) may be included in the display (180) or may be a separately provided panel.

[0072] Hereinafter, it is assumed that the shading panel (210) is a panel provided separately from the display (180). The shading panel (210) can block light incident on the display (180) through an electronic shading method. The shading panel (210) can selectively block light incident on the display (180) through an electronic shading method.

[0073] The shading panel (210) can locally block light incident on the display (180).

[0074] In the case of an electronic shading method, the transmittance of a local area of ​​the display (180) is electrically controlled, so that the shading state of the display (180) can be controlled.

[0075] The light-shielding panel (210) may be any one of a liquid crystal display (LCD) panel, a micro electro mechanical system (MEMS) panel, an electro wetting, or an electro chromic panel. When an LCD panel is used as the light-shielding panel (210), the light-shielding method may be referred to as a liquid crystal shutter method.

[0076] The controller (170) or the image driving circuit (not shown) can control the light-blocking panel (210) to control the transmittance corresponding to a portion or the entire area of ​​the display (180). The image driving circuit may be included in the controller (170) or may be a component provided separately from the controller (170). Each of the controller (170) or the image driving circuit may be configured as a single chip.

[0077] First, an example in which the transmittance is locally controlled when the shading panel (210) is an LCD panel (210) is described.

[0078] The controller (170) can control the arrangement of liquid crystal molecules corresponding to an area of ​​the display (180) by transmitting a control signal to the LCD panel (210), thereby adjusting the transmittance for the corresponding area.

[0079] The control signal that controls the arrangement of liquid crystal molecules may be a voltage signal that controls the voltage applied to the liquid crystal layer of the LCD panel (210).

[0080] The LCD panel (210) may include two polarizing plates, a thin film transistor (TFT), and a liquid crystal layer. Each of the two polarizing plates may transmit light in one direction and block light in the other direction.

[0081] A TFT can be a switching element that applies and blocks a voltage signal to the liquid crystal layer, which controls the arrangement of liquid crystal molecules. The liquid crystal molecules in the liquid crystal layer can be aligned according to the voltage signal received from the TFT. Light can be passed through or blocked depending on the arrangement of the liquid crystal molecules.

[0082] Light can pass through the first polarizing plate and then the liquid crystal layer. If the polarization direction of the light changes in the liquid crystal layer, it can pass through the second polarizing plate. Depending on the arrangement of the liquid crystals, if the polarization direction of the light changes, the amount of light passing through the second polarizing plate may vary.

[0083] This allows the transmittance of the LCD panel (210) to be adjusted. The transmittance may be referred to as transmittance.

[0084] The controller (170) can locally control the transmittance of a specific area by applying or blocking voltage only to pixels in a specific area through electrodes arranged in a matrix form of the LCD panel (210).

[0085] A MEMS panel may consist of a substrate, a thin film layer, an air layer, and a reflective layer. A MEMS panel can display images in two states: an open state and a collapsed state.

[0086] When no voltage is applied, MEMS panels have separate thin film layers, allowing for selective reflection. However, when a low voltage is applied, electrostatic forces are generated, causing the reflective film layers to move, absorbing all light. Thus, MEMS panels can control light transmittance through the thin film and reflective film layers.

[0087] An electrowetting panel may be a panel that controls the reflectivity and transmittance of the surface of the panel by utilizing changes in the shape of liquid droplets.

[0088] FIGS. 3A and 3B are drawings illustrating various forms of a display according to an embodiment of the present disclosure.

[0089] Referring to FIG. 3A, a pixel may include a light emitting region and a transparent region. In the light emitting region, RGBW (Red, Green, Blue, White) subpixels may be arranged vertically, and the transparent region without subpixels may be arranged next to the light emitting region.

[0090] Accordingly, a display (180) having a plurality of pixels can not only display an image but also transmit light. The display (180) may be referred to as a transparent display panel or a transparent OLED (Organic Light Emitting Diode) panel.

[0091] Referring to FIG. 3B, a pixel may include a light emitting region and a transparent region. In the light emitting region, subpixels of RGW (Red, Green, White) or BGW (Blue, Green, White) may be arranged adjacent to each other, and the transparent region without subpixels may be arranged next to the light emitting region.

[0092] Accordingly, a display (180) having a plurality of pixels can not only display an image but also transmit light. The display (180) may be referred to as a transparent display, a transparent display panel, or a transparent OLED panel.

[0093] Meanwhile, each subpixel may include an organic light-emitting layer, a cathode, and an anode. When current flows through the organic light-emitting layer, light may be emitted. The display (180) may emit light having a specific wavelength using the organic light-emitting layer.

[0094] FIG. 4 is a flowchart for explaining an operating method of a display device according to an embodiment of the present disclosure.

[0095] A display device (100) may include a first panel for displaying an image, a second panel for blocking at least a portion of the first panel, and a controller (170) for controlling the first panel and the second panel.

[0096] The display (180) may be referred to as a first panel (180), and the light-shielding panel (210) may be referred to as a second panel (210).

[0097] Referring to FIG. 4, the controller (170) of the display device (100) can obtain image information of an image displayed on the first panel (180) (S401).

[0098] In one embodiment, the image information may include image data applied to each of a plurality of pixels included in the first panel (180). The image data may include a pixel value applied to each pixel.

[0099] If a pixel includes a red subpixel, a green subpixel, and a blue subpixel, the pixel value may include a value applied to the red subpixel, a value applied to the green subpixel, and a value applied to the blue subpixel.

[0100] If a pixel includes a red subpixel, a green subpixel, a blue subpixel, and a white subpixel, the pixel value may include a value applied to the red subpixel, a value applied to the green subpixel, a value applied to the blue subpixel, and a value applied to the white subpixel.

[0101] In another embodiment, the image information may include a gray level applied to each of a plurality of pixels included in the first panel (180). The controller (170) may obtain the gray level of the pixel based on the pixel value applied to each of the plurality of pixels.

[0102] In another embodiment, the image information may include luminance for at least a portion of the first panel (180).

[0103] In another embodiment, the image information may include main objects and background objects included in the image.

[0104] The controller (170) can control the transmittance of the second panel (210) based on the acquired image information (S403).

[0105] In one embodiment, the controller (170) can locally control the transmittance of the second panel (210) based on the acquired image information. For example, the controller (170) can control the transmittance of a first region of the second panel (210) to a first transmittance based on the acquired image information, and can control the transmittance of a second region to a second transmittance different from the first transmittance.

[0106] The controller (170) can identify a specific area of ​​the first panel (180) where the same image is displayed for a certain period of time in a fixed position, such as a logo, channel number, a stationary object, or a background, and control the transmittance of a partial area of ​​the second panel (210) corresponding to the specific area. An image displayed for a certain period of time in a specific area among the entire area of ​​the first panel (180) can be referred to as a fixed image or a specific image. The specific area can be referred to as a fixed area.

[0107] A fixed area can be an area where a logo, channel number, menu, or information is displayed.

[0108] For example, the controller (170) can reduce the transmittance of a partial area of ​​the second panel (210) corresponding to a fixed image displayed on the first panel (180).

[0109] The controller (170) can reduce the transmittance of a partial region of the second panel (210) in proportion to the time for which the fixed image is displayed on the first panel (180). For example, the controller (170) can reduce the transmittance of a partial region of the second panel (210) corresponding to the fixed image as the display time of the fixed image increases.

[0110] The controller (170) can reduce the transmittance of a partial area of ​​the second panel (210) and reduce the brightness of a specific area of ​​the first panel (180) where a fixed image is displayed.

[0111] A fixed image displayed on the first panel (210) can easily cause afterimages. In an embodiment of the present disclosure, the transmittance of a partial region of the second panel (210) corresponding to the fixed image can be reduced, thereby darkening the rear background of the partial region. This allows the same image quality to be maintained even when the brightness of the fixed region where the fixed image is displayed is lowered.

[0112] Accordingly, even if the luminance of the fixed area is reduced, afterimages in the fixed area can be prevented while maintaining the same image quality. Furthermore, power consumption can be reduced because the current applied to the fixed area is reduced.

[0113] In another embodiment, the controller (170) may extract a portion of the entire area of ​​the first panel (180) where the gray level is below a certain level, and reduce the transmittance of a portion of the second panel (210) corresponding to the extracted portion of the area. For example, the portion of the area where the gray level is below a certain level may be either a black area or a pure color area.

[0114] In another embodiment, the controller (170) can extract a portion of the entire area of ​​the first panel (180) whose brightness is greater than or equal to a preset value, and reduce the transmittance of an area of ​​the second panel (210) corresponding to the extracted portion of the area. The controller (170) can reduce the brightness of a portion of the area whose brightness is greater than or equal to the preset value.

[0115] FIGS. 5 to 6B are drawings illustrating a process for preventing afterimages caused by a fixed image displayed on a first panel according to an embodiment of the present disclosure.

[0116] The flowchart of FIG. 5 may be a diagram that embodies step S403 of FIG. 4.

[0117] Referring to FIG. 5, the controller (170) of the display device (100) can determine whether the same image data is applied to a specific area among the entire area of ​​the first panel (180) for a certain period of time or longer based on image information of the image displayed on the first panel (180) (S501).

[0118] The controller (170) can determine whether the same pixel value or the same gray level is applied to a specific area of ​​the first panel (180) for a certain period of time or longer.

[0119] The time period may be 10 minutes, but this is only an example.

[0120] If the controller (170) determines that the same image data is applied to a specific area of ​​the entire area of ​​the first panel (180) for a certain period of time, the controller (170) can control the second panel (210) so that the transmittance of a partial area of ​​the second panel (210) corresponding to the specific area is reduced (S503).

[0121] If the controller (170) determines that the same image data is applied to a specific area of ​​the first panel (180) for a certain period of time or longer, the controller (170) can identify the specific area as an area where a fixed image is displayed. The controller (170) can obtain coordinates indicating the location of the specific area.

[0122] The controller (170) may apply a transmittance control signal to the second panel (210) to reduce the transmittance of a partial region of the second panel (210) corresponding to a specific region of the first panel (180). The transmittance control signal may include coordinate information indicating the location of the specific region and transmittance information requesting a reduction in transmittance. The transmittance information may include the transmittance to be reduced.

[0123] The second panel (210) can reduce the transmittance of a partial area of ​​the second panel (210) corresponding to a specific area based on a transmittance control signal received from the controller (170).

[0124] The controller (170) can control the first panel (180) so that the brightness of the specific area of ​​the first panel (180) is reduced (S505).

[0125] As the transmittance of a partial region of the second panel (210) decreases, the rear background of the partial region may have the effect of darkening. As the rear background of the partial region becomes darker, the fixed image displayed in a specific region of the first panel (180) corresponding to the partial region may have the effect of becoming clearer. In other words, as the transmittance of the partial region decreases and background light is blocked, the brightness of the image perceived by the viewer may increase.

[0126] In this case, even if the brightness of a specific area of ​​the first panel (180) is lowered, the image quality of the fixed image displayed on the specific area can be maintained the same.

[0127] The controller (170) can transmit a brightness control signal to the first panel (180) to lower the brightness of a specific area of ​​the first panel (180) by a certain value. The first panel (180) can control the current flowing in the organic light-emitting layer of the pixels included in the specific area to reduce the brightness of the specific area according to the brightness control signal.

[0128] That is, the controller (170) can reduce the current flowing in the organic light-emitting layer of pixels included in a specific area so as to reduce the brightness of a specific area of ​​the first panel (180). Accordingly, the effect of preventing afterimages occurring in a specific area of ​​the first panel (180) can be obtained, and the effect of reducing power consumption can be obtained.

[0129] Referring to FIG. 6A, a fixed image (610) may be displayed on a specific area of ​​the display (180). The fixed image (610) may be a logo image representing a logo.

[0130] When a fixed image (610) is displayed on the first panel (180) for a certain period of time, the controller (170) can reduce the transmittance of a partial area (630) of the second panel (210) corresponding to the fixed image (610).

[0131] The partial area (630) may be an area corresponding to a fixed image (610, the text image of the LOGO itself) or a rectangular area including the fixed image (610).

[0132] The image driving circuit (600) can control the first panel (180) to reduce the brightness of the fixed image (610) when the fixed image (610) is displayed on the first panel (610) for a certain period of time or longer, and can control the second panel (210) to reduce the transmittance of the partial area (630).

[0133] The image driving circuit (600) may be included in the controller (170) or provided separately from the controller (170).

[0134] The image driving circuit (600) can reduce the current flowing in the organic light-emitting layer of each pixel included in the fixed area of ​​the first panel (180) to reduce the brightness of the fixed image (610).

[0135] When the second panel (210) is an LCD panel, the image driving circuit (600) can control the voltage applied to each pixel provided in the partial area of ​​the second panel (210) to reduce the transmittance of the partial area (630).

[0136] Meanwhile, according to an embodiment of the present disclosure, the fixed area may be a banner area where a banner is displayed. The banner area may include text indicating information, and the text may change at regular intervals.

[0137] The controller (170) can reduce the transmittance of an area of ​​the second panel (210) corresponding to the remaining area except for the text that changes every short time included in the banner area displayed on the first panel (180). The controller (170) can reduce the brightness of the remaining area among the banner areas of the first panel (180).

[0138] FIG. 7 is a drawing explaining the relationship between transmittance and luminance according to an embodiment of the present disclosure.

[0139] The luminance of the fixed area where the fixed image (610) of the first panel (180) is displayed and the transmittance of the partial area (630) of the second panel (210) corresponding to the fixed area may be in a proportional relationship.

[0140] The luminance of a fixed area can be replaced by the current applied to the pixels contained in the fixed area.

[0141] The controller (170) can reduce the brightness of the fixed area of ​​the first panel (180) as the transmittance of the partial area (630) of the second panel (210) decreases.

[0142] In one embodiment, the memory (140) of the display device (100) may store a lookup table indicating a correspondence between the luminance of a fixed area where a fixed image (610) is displayed and the transmittance of a partial area (630) of a second panel (210) corresponding to the fixed area.

[0143] When the controller (170) obtains the transmittance of a partial area (630) of the second panel (210), it can extract the luminance matching the transmittance using a lookup table.

[0144] The graph in Fig. 7 can represent a luminance-transmittance compensation logic that reduces luminance as transmittance decreases.

[0145] FIG. 8 is a drawing illustrating a method for preventing afterimages when displaying a menu or information displayed at a fixed location on a first panel according to one embodiment of the present disclosure.

[0146] In particular, in FIG. 8, the first panel (180) assumes that a pixel shift technique is used to prevent afterimages.

[0147] The display device (100) may perform a pixel shift operation when a time information image (810) is displayed on the first panel (180) for a certain period of time or longer. The pixel shift operation may be an operation that minutely moves the time information image (810) so that a continuous load is not applied to specific pixels. The time information image (810) may be moved alternately in the up, down, left, and right directions.

[0148] The display device (100) can reduce the transmittance of an area (830) of the second panel (210) corresponding to the time information image (810). The display device (100) can also move the area (830) of the second panel (210) as the time information image (810) moves, thereby reducing the transmittance of the moved area (830).

[0149] The display device (100) can reduce the brightness of an area of ​​the first panel (180) where a time information image (810) is displayed. When the time information image (810) moves, the display device (100) can reduce the brightness of an area of ​​the first panel (180) that moves in accordance with the movement of the time information image (810).

[0150] Accordingly, the afterimage prevention effect can be maximized while the image quality of the time information image (810) remains the same.

[0151] FIG. 9 is a flowchart illustrating a method of operating a display device according to another embodiment of the present disclosure.

[0152] Fig. 9 may be an embodiment that embodies step S403 of Fig. 4. Fig. 9 may be an embodiment that recognizes a main object and a background object displayed on a first panel (180) and controls the transmittance of a main area of ​​a second panel (210) corresponding to the main object and the transmittance of a background area of ​​the second panel (210) corresponding to the background object.

[0153] Referring to FIG. 9, the controller (170) can obtain the main object and background object based on the image information of the image displayed on the first panel (180) (S901).

[0154] In one embodiment, image information may include feature points of the image. Each feature point may represent an edge of an object. The controller (170) may extract a plurality of feature points from the image and obtain an outline connecting the extracted feature points.

[0155] The controller (170) can recognize the area formed by the outline as the main object. The controller (170) can identify an area other than the main object as a background object.

[0156] In another embodiment, the controller (170) can extract key objects and background objects from image frames constituting an image using an artificial intelligence model. The artificial intelligence model is a deep learning or machine learning-based model and can extract key objects from image frames. The artificial intelligence model may be a model using a convolutional neural network (CNN) algorithm or a YOLO (You Only Look Once) algorithm.

[0157] The main object can be any of a person, an animal, or an object.

[0158] The main object may be referred to as the main image or main region, and the background object may be referred to as the background image or background region.

[0159] In another embodiment, the main object may represent an area where the luminance is greater than a preset value.

[0160] The controller (170) can reduce the transmittance of a main area of ​​the second panel (210) corresponding to the main object and increase the transmittance of a background area of ​​the second panel (210) corresponding to the background object (S903).

[0161] The controller (170) can control the second panel (210) to reduce the transmittance of a main area of ​​the second panel (210) corresponding to the location of the main object and to increase the transmittance of a background area of ​​the second panel (210) corresponding to the background object.

[0162] Accordingly, the difference in contrast between the main object and the background object can be maximized.

[0163] FIG. 10 is a flowchart illustrating a method of operating a display device according to another embodiment of the present disclosure.

[0164] The controller (170) can obtain the maximum brightness area and the minimum brightness area based on the image information of the image displayed on the first panel (180) (S1001).

[0165] The controller (170) can extract pixels having a brightness greater than or equal to a preset first value using the pixel values ​​of each of the plurality of pixels included in the image information. The controller (170) can acquire the area formed by the extracted pixels as a maximum brightness area. The maximum brightness area may be a pure color area.

[0166] The controller (170) can extract pixels having a brightness lower than a preset second value using the pixel values ​​of each of the plurality of pixels included in the image information. The controller (170) can acquire the area formed by the extracted pixels as a minimum brightness area. The minimum brightness area may be a black area.

[0167] The controller (170) can reduce the transmittance of the first transmission area of ​​the second panel (210) corresponding to the maximum brightness area and the second transmission area of ​​the second panel (210) corresponding to the minimum brightness area (S1003).

[0168] The controller (170) can reduce the transmittance of the first transmission area of ​​the second panel (210) corresponding to the maximum brightness area and the second transmission area of ​​the second panel (210) corresponding to the minimum brightness area to a preset transmittance.

[0169] In particular, when inputting HDR (High Dynamic Range) images, the contrast ratio with the remaining areas can be maximized by reducing the transmittance of the maximum and minimum brightness areas. This can enhance the effect of HDR images, which maximize the difference between bright and dark areas.

[0170] FIG. 11 is a drawing illustrating an example of reducing the transmittance of a maximum brightness area and a minimum brightness area of ​​an image according to an embodiment of the present disclosure.

[0171] Referring to FIG. 11, an image (1110) may be displayed on a first panel (180). The image (1110) may be an HDR image. The controller (170) of the display device (100) may extract a minimum brightness area (1111) and a maximum brightness area (1113) from the image (1110).

[0172] The controller (170) can obtain coordinate information for the areas occupied by each of the minimum brightness area (1111) and the maximum brightness area (1113).

[0173] The controller (170) can use the acquired coordinate information to identify the first transparent area (1131) of the second panel (210) corresponding to the minimum brightness area (1111) and the second transparent area (1133) of the second panel (210) corresponding to the maximum brightness area (1113).

[0174] The controller (170) can reduce the transmittance of each of the first transparent region (1131) and the second transparent region (1133). The controller (170) can control the second panel (210) so that the transmittance of each of the first transparent region (1131) and the second transparent region (1133) becomes 10.

[0175] Accordingly, the contrast ratio between the minimum brightness area (1111), the maximum brightness area (1113), and the remaining areas can be maximized. When the contrast ratio is maximized, the image quality can be improved, and the color reproducibility can be enhanced.

[0176] FIGS. 12 and 13 are flowcharts illustrating a process of controlling at least one of a first panel or a second panel based on front brightness and back brightness of a display device according to an embodiment of the present disclosure.

[0177] Referring to FIG. 12, the controller (170) of the display device (100) can obtain the front brightness and the rear brightness of the first panel (180) (S1201).

[0178] The front of the first panel (180) may be the side on which the viewer watches the video, and the back of the first panel (180) may be the opposite side of the front.

[0179] A light sensor may be provided on each of the front and rear surfaces of the first panel (180). The controller (170) may obtain the front brightness and rear brightness of the first panel (180) using the two light sensors.

[0180] The controller (170) can determine whether the rear brightness is greater than the front brightness (S1203), and if the rear brightness is greater than the front brightness, the brightness of the first panel (180) can be adjusted to a value greater than or equal to a reference brightness value (S1205).

[0181] The controller (170) can change the brightness of the first panel (180) to a value higher than the reference brightness value to improve visibility when the rear brightness is greater than the front brightness.

[0182] The controller (170) can adjust the brightness of the first panel (180) to be less than the reference brightness value when the acquired rear brightness is less than the front brightness (S1207).

[0183] The controller (170) can change the brightness of the first panel (180) to be less than or equal to the reference brightness when the rear brightness is lower than the front brightness. This is because, as the background becomes darker, even if the brightness is low, the effect on visibility is reduced.

[0184] Next, Fig. 13 is described.

[0185] The controller (170) of the display device (100) can obtain the front brightness and rear brightness of the first panel (180) (S1301).

[0186] The controller (170) can determine whether the rear brightness is greater than the front brightness (S1303), and if the rear brightness is greater than the front brightness, the transmittance of the second panel (210) can be reduced (S1305).

[0187] The controller (170) can change the transmittance of the second panel (180) to be less than the reference transmittance to improve visibility when the rear brightness is greater than the front brightness.

[0188] The controller (170) can increase the transmittance of the second panel (210) when the acquired rear brightness is less than the front brightness (S1307).

[0189] The controller (170) can change the transmittance of the second panel (210) to be less than or equal to the standard transmittance when the rear brightness is lower than the front brightness. This is because as the background darkens, the effect on visibility decreases even when the transmittance increases.

[0190] FIG. 14 is a drawing illustrating an embodiment of adjusting the transmittance or brightness of a bright image area of ​​an HDR image according to the surrounding brightness when an HDR image is input according to an embodiment of the present disclosure.

[0191] The controller (170) can obtain a bright image area based on image information of the image displayed on the first panel (180) (S1401).

[0192] The image information may include metadata indicating that the image input to the first panel (180) is an HDR image.

[0193] The controller (170) can extract a bright image area from the entire area of ​​an HDR image. The controller (170) can extract pixels having a brightness greater than or equal to a preset first value using the pixel values ​​of each of a plurality of pixels included in the image information. The controller (170) can acquire the area formed by the extracted pixels as a bright image area.

[0194] The controller (170) can obtain the ambient brightness of the display device (S1403).

[0195] A light sensor may be provided on the first panel (180) or the second panel (210). The controller (170) may measure the ambient brightness through the sensing value measured by the light sensor.

[0196] The controller (170) can determine whether the acquired ambient brightness is above a certain brightness (S1405).

[0197] If the controller (170) determines that the acquired ambient brightness is higher than a certain brightness, it can control the second panel (210) to lower the transmittance of the transmission area of ​​the second panel (210) corresponding to the bright image area (S1407).

[0198] If the acquired ambient brightness is determined to be above a certain brightness, the controller (170) may lower the transmittance of the transmission area of ​​the second panel (210) corresponding to the bright image area to improve the visibility of the bright image area (to display it brighter). The controller (170) may lower the transmittance of the transmission area of ​​the second panel (210) corresponding to the bright image area to the maximum.

[0199] If the controller (170) determines that the acquired ambient brightness is less than a certain brightness, it can increase the transmittance of the transmission area of ​​the second panel (210) corresponding to the bright image area and control the first panel (180) to increase the brightness of the bright image area (S1409).

[0200] If the controller (170) determines that the acquired ambient brightness is less than a certain brightness, the controller (170) can control the first panel (180) to increase the brightness of the bright image area instead of increasing the transmittance of the transmission area of ​​the second panel (210) corresponding to the bright image area.

[0201] In this way, according to an embodiment of the present disclosure, when an HDR image is input, the contrast ratio of the image can be significantly improved by adjusting the transmittance or luminance of a bright image area of ​​the HDR image according to the surrounding brightness.

[0202] In the embodiment of Fig. 14, it can also be applied to the dark image area of ​​the HDR image. In another embodiment, the controller (170) can extract the dark image area from the entire area of ​​the HDR image. The controller (170) can extract pixels having a brightness lower than a preset second value using the pixel value of each of the plurality of pixels included in the image information. The controller (170) can obtain the area formed by the extracted pixels as the dark image area.

[0203] FIG. 15 is a drawing illustrating a configuration of a display device according to another embodiment of the present disclosure.

[0204] A display device (100-1) according to another embodiment of the present disclosure may include a first panel (180), a second panel (210), and a controller (170).

[0205] The first panel (180) can display an image. The first panel (180) can be a transparent OLED display panel.

[0206] The second panel (210) may be a light-blocking panel capable of blocking light. The second panel (210) may block light in at least a portion of an area corresponding to the first panel (180). The second panel (210) may locally block light in at least a portion of an area corresponding to the first panel (180).

[0207] The second panel (210) may be any one of an LCD panel, a MEMS panel, or an electrowetting panel.

[0208] The controller (170) can obtain image information of the image displayed on the first panel (180).

[0209] The controller (170) can control the transmittance of the second panel (210) based on the acquired image information.

[0210] A display device (100-1) according to an embodiment of the present disclosure may include a first panel (180) that includes a plurality of pixels and displays a transparent image through the plurality of pixels, a second panel (210) that is arranged on one side of the first panel (180) and is controlled to allow light to selectively transmit through an area of ​​the first panel, and a controller (170) that obtains image information of the image displayed on the first panel and controls the transmittance of the second panel based on the obtained image information.

[0211] The image information may be a gray level applied to each of the plurality of pixels, and the controller (170) may control the second panel (210) so that the transmittance of a portion of the second panel corresponding to a portion of the first panel (180) where the gray level is below a certain level is reduced.

[0212] The above image information may be a pixel value applied to each of the plurality of pixels, and the controller (170) may identify a fixed area of ​​the first panel (180) to which the same pixel value is applied for a certain period of time or longer, and control the second panel (210) so that the transmittance of a partial area of ​​the second panel (210) corresponding to the fixed area is reduced.

[0213] The above controller (170) can control the first panel (210) to reduce the brightness of the fixed area of ​​the first panel (180).

[0214] The fixed area of ​​the first panel (210) may be an area where a logo, channel number, menu, or information is displayed.

[0215] The above controller (170) can also move a partial area of ​​the second panel (210) to match the movement of the fixed area when the fixed area is moved to prevent afterimages.

[0216] The controller (170) can locally control the transmittance of the second panel (210) based on the acquired image information.

[0217] The controller (170) can adjust the transmittance of the first area of ​​the second panel (210) to a first transmittance based on the image information, and can adjust the transmittance of the second area of ​​the second panel (210) to a second transmittance different from the first transmittance.

[0218] The controller (170) can obtain a main image and a background image from the image based on the image information, reduce the transmittance of the first area of ​​the second panel corresponding to the main image, and increase the transmittance of the second area of ​​the second panel.

[0219] The second panel (210) may be any one of a liquid crystal display (LCD) panel, a micro electro mechanical system (MEMS) panel, or an electro wetting panel.

[0220] According to one embodiment of the present disclosure, the above-described method can be implemented as processor-readable code on a medium in which a program is recorded. Examples of processor-readable media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, and optical data storage devices.

Claims

1. In the display device, A video receiving unit that receives a video; A first panel including a plurality of pixels and displaying the image received by the image receiving unit through the plurality of pixels; A second panel arranged on one side of the first panel and controlled to selectively transmit light to an area of ​​the first panel; and A controller that obtains image information of the image displayed on the first panel and controls the transmittance of the second panel based on the obtained image information. Display device.

2. In paragraph 1, The above video information is the gray level applied to each of the above plurality of pixels, The above controller Controlling the second panel so that the transmittance of a portion of the second panel corresponding to a portion of the first panel where the gray level is below a certain level is reduced. Display device.

3. In paragraph 1, The above video information is a pixel value applied to each of the above plurality of pixels, The above controller Identifying a fixed area of ​​the first panel to which the same pixel value is applied for a certain period of time, Controlling the second panel so that the transmittance of a partial area of ​​the second panel corresponding to the fixed area is reduced. Display device.

4. In paragraph 3, The above controller Controlling the first panel to reduce the brightness of the fixed area of ​​the first panel Display device.

5. In paragraph 3, The fixed area of ​​the above first panel is The area where the logo, channel number, menu or information is displayed. Display device.

6. In paragraph 3, The above controller In order to prevent afterimages, when the fixed area is moved, a partial area of ​​the second panel is also moved to match the movement of the fixed area. Display device.

7. In paragraph 1, The above controller Based on the acquired image information, the transmittance of the second panel is locally controlled. Display device.

8. In paragraph 7, The above controller Based on the image information, the transmittance of the first area of ​​the second panel is adjusted to a first transmittance, and the transmittance of the second area of ​​the second panel is adjusted to a second transmittance different from the first transmittance. Display device.

9. In paragraph 8, The above controller Based on the above image information, main images and background images are obtained from the image, Reducing the transmittance of the first region of the second panel corresponding to the main image and increasing the transmittance of the second region of the second panel Display device.

10. In paragraph 1, The second panel above Any one of a Liquid Crystal Display (LCD) panel, a Micro Electro Mechanical System (MEMS) panel, or an Electro wetting panel. Display device.

11. In paragraph 1, The above controller Based on the above image information, if the image is an HDR (High Dynamic Range) image, a bright image area is extracted from the entire area of ​​the HDR image, Obtain the ambient brightness of the above display device, When the acquired ambient brightness is higher than a certain brightness, the second panel is controlled to lower the transmittance of the transmission area of ​​the second panel corresponding to the bright image area, When the acquired ambient brightness is less than the predetermined brightness, the second panel is controlled to increase the transmittance of the transmission area of ​​the second panel corresponding to the bright image area, and the first panel is controlled to increase the brightness of the bright image area. Display device.

12. A method for operating a display device including an image receiving unit that receives an image, a first panel that includes a plurality of pixels and displays an image received by the image receiving unit through the plurality of pixels, and a second panel that is arranged on one side of the first panel and whose area of ​​the first panel is controlled to selectively transmit light, A step of obtaining image information of the image displayed on the first panel; and A step of controlling the transmittance of the second panel based on the acquired image information. How the display device operates.

13. In paragraph 12, The above video information is the gray level applied to each of the above plurality of pixels, The step of controlling the transmittance of the second panel is A step of controlling the second panel so that the transmittance of a portion of the second panel corresponding to a portion of the first panel where the gray level is below a certain level is reduced. How the display device operates.

14. In paragraph 12, The above video information is a pixel value applied to each of the above plurality of pixels, The step of controlling the transmittance of the second panel is A step of identifying a fixed area of ​​the first panel to which the same pixel value is applied for a certain period of time or longer; and A step of controlling the second panel so that the transmittance of a partial area of ​​the second panel corresponding to the fixed area is reduced. How the display device operates.

15. In paragraph 14, Further comprising a step of controlling the first panel to reduce the brightness of the fixed area of ​​the first panel. How the display device operates.

Images