Display device

Abstract

A display device is provided. The display device includes a pixel unit including first pixels arranged in a first pixel area and second pixels arranged in a second pixel area, an image data corrector adjusting a limited gray scale of first image data corresponding to the first pixel area based on a dimming level defining a maximum luminance at which the pixel unit is capable of emitting light, and correcting the first image data based on the limited gray scale, a data driver supplying a data signal to the pixel unit based on the corrected first image data and second image data corresponding to the second pixel area, and a scan driver supplying a scan signal to the pixel unit.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2020-0088430, filed on July 16, 2020, which is hereby incorporated by reference for all purposes, as if fully set forth herein. Technical Field

[0003] Exemplary embodiments of the present invention generally relate to display devices, and more specifically, to display devices in which brightness can be controlled differently depending on the position in the pixel unit. Background Technology

[0004] Display devices can display images using pixels (or pixel circuits). A display device may include sensors, cameras, and the like in the bezel (or edge portion) of its front surface (e.g., the surface on which an image is displayed). For example, a display device may identify objects using an optical sensor and acquire photographs and / or videos using a camera.

[0005] Recently, cameras or similar components have been arranged to overlap with pixel areas to minimize bezels. To improve the transmittance of the area where the camera is located, the resolution of the overlapping area can be designed to be lower than that of other display areas, and the brightness of each area will vary due to this difference in resolution.

[0006] The information disclosed in this background section is only for understanding the background of the inventive concept, and therefore may contain information that does not constitute prior art. Summary of the Invention

[0007] An apparatus constructed according to an exemplary embodiment of the present invention can provide a display device that can limit the maximum gray level (limit gray level) of image data corresponding to a first pixel region having low resolution based on a dimming level, and can control the output gray level of the limit gray level or a lower gray level.

[0008] An apparatus constructed according to an exemplary embodiment of the present invention can provide an image data compensator included in a display device.

[0009] Additional features of the inventive concept will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the inventive concept.

[0010] One or more exemplary embodiments of the present invention provide a display device, the display device including a pixel unit, an image data corrector, a data driver, and a scan driver. The pixel unit includes a first pixel disposed in a first pixel region and a second pixel disposed in a second pixel region. The image data corrector adjusts a limit grayscale of first image data corresponding to the first pixel region based on a dimming level that defines the maximum brightness at which the pixel unit can emit light, and corrects the first image data based on the limit grayscale. The data driver supplies a data signal to the pixel unit based on the corrected first image data and the second image data corresponding to the second pixel region. The scan driver supplies a scan signal to the pixel unit.

[0011] The number of first pixels per unit area can be less than the number of second pixels per unit area.

[0012] The image data corrector may include a limit grayscale controller that determines the limit grayscale of the first image data based on the ratio between the dimming level and a preset reference brightness.

[0013] The reference brightness can be the brightness of the first pixel region when the first pixel emits light through the maximum driving current that can be generated in the first pixel.

[0014] Converts input grayscale values ​​greater than or equal to the limit grayscale value, and outputs grayscale values ​​less than or equal to the limit grayscale value.

[0015] For the same input gray level that is greater than or equal to the limit gray level, the voltage of the data signal supplied to the first pixel and the voltage of the data signal supplied to the second pixel can be different from each other.

[0016] The limit gray level corresponding to the first dimming level may be less than the limit gray level corresponding to the second dimming level, and the maximum brightness of the first dimming level may be greater than the maximum brightness of the second dimming level.

[0017] The grayscale range of the corrected first image data corresponding to the first dimming level may be smaller than the grayscale range of the corrected first image data corresponding to the second dimming level.

[0018] The grayscale range of the corrected first image data can be smaller than the grayscale range of the second image data.

[0019] The image data corrector may also include a grayscale mapper that non-linearly maps the input and output grayscale of the first image data based on a limit grayscale.

[0020] The image data corrector may also include a grayscale enhancer that enhances the input grayscale in a first grayscale range based on the ratio between a reference brightness and a dimming level, and the first grayscale range may include input grayscale values ​​less than a limit grayscale value.

[0021] A grayscale enhancer can determine the enhancement ratio by using the ratio between a reference brightness and a dimming level, and can determine the first grayscale range by using the enhancement ratio and a limit grayscale value.

[0022] The first data signal supplied to the first pixel and the second data signal supplied to the second pixel may be different from the first input gray level included in the first gray level range.

[0023] The third data signal supplied to the first pixel and the fourth data signal supplied to the second pixel may be different relative to the second input gray level which is greater than or equal to the limit gray level.

[0024] When the driving transistor of each of the first pixel and the second pixel is a p-channel driving transistor, the voltage of the first data signal can be less than the voltage of the second data signal, and the voltage of the third data signal can be greater than the voltage of the fourth data signal.

[0025] At the first dimming level, the first output gray level corresponding to the first input gray level can be greater than the second output gray level corresponding to the first input gray level at the second dimming level.

[0026] The maximum brightness of the first dimming level can be greater than the maximum brightness of the second dimming level.

[0027] The grayscale mapper non-linearly maps the input and output grayscale of the first image data based on a limit grayscale and an enhancement ratio.

[0028] One or more exemplary embodiments of the present invention provide an image data corrector capable of correcting image data of pixels in a pixel unit comprising a first pixel region and a second pixel region. The image data corrector may include a limit grayscale controller that determines a limit grayscale of the image data based on a ratio between a dimming level defining a maximum brightness of the pixel unit and a preset reference brightness of the first pixel region.

[0029] The reference brightness can be the brightness of the first pixel region when the pixel emits light by the maximum driving current that can be generated in the pixels of the first pixel region.

[0030] The image data corrector may also include a grayscale enhancer and a grayscale mapper. The grayscale enhancer determines the enhancement ratio by using the ratio between a reference brightness and a dimming level and determines a first grayscale range by using the enhancement ratio and a limit grayscale. The grayscale mapper non-linearly maps the input grayscale and output grayscale of the image data based on the limit grayscale and the enhancement ratio.

[0031] The maximum enhanced gray level, including within the first gray level range, can be less than the limit gray level.

[0032] According to embodiments of the present invention, an image data corrector and a display device including the image data corrector can adaptively limit the grayscale and gamma voltage of image data corresponding to a first pixel region having a relatively low pixel density based on a dimming level. Therefore, high brightness and high grayscale driving that cannot be achieved in the first pixel region can be prevented in advance by image data correction. Accordingly, data signals corresponding to unnecessary grayscale values ​​may not be supplied to the first pixel region, the gamma characteristics of the output of the first pixel region may not be distorted, and the driving transistor of the first pixel may operate relatively stably.

[0033] Furthermore, the image data corrector according to embodiments of the present invention and the display device including the image data corrector can adaptively enhance gray levels other than a limited input gray level according to the dimming level. Therefore, the brightness of the first pixel region for input gray levels of intermediate gray levels (e.g., approximately 100 gray levels) or lower gray levels can be increased. Accordingly, when an image is displayed based on input image data of intermediate or lower gray levels, the brightness difference between the first pixel region and the second pixel region with different resolutions can be minimized.

[0034] It will be understood that both the foregoing general description and the following detailed description are exemplary and explanatory, and are intended to provide further explanation of the claimed invention. Attached Figure Description

[0035] The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the invention and, together with the description, serve to explain the inventive concept.

[0036] Figure 1 A schematic diagram of a display device according to an exemplary embodiment of the present invention is shown.

[0037] Figure 2 It shows Figure 1 A schematic diagram of an example of a pixel unit of a display device.

[0038] Figure 3 A block diagram of a display device according to an exemplary embodiment of the present invention is shown.

[0039] Figure 4 It shows that it includes Figure 3 A block diagram of an example image data corrector in a display device.

[0040] Figure 5A , Figure 5B and Figure 5C It shows from Figure 4 A graph showing an example of the corrected first image data output by the image data corrector.

[0041] Figure 6A , Figure 6B and Figure 6C It shows from Figure 4 A graph of another example of the corrected first image data output by the image data corrector.

[0042] Figure 7 It shows that it includes Figure 3 A block diagram of another example of an image data corrector in a display device.

[0043] Figure 8A , Figure 8B and Figure 8C It shows from Figure 7 A graph showing an example of the corrected first image data output by the image data corrector.

[0044] Figure 9A , Figure 9B and Figure 9C It shows from Figure 7 A graph of another example of the corrected first image data output by the image data corrector. Detailed Implementation

[0045] In the following description, numerous specific details are set forth for purposes of explanation to provide a thorough understanding of various exemplary embodiments or implementations of the invention. As used herein, “implementation” and “method” are interchangeable terms and are non-limiting examples of apparatuses or methods employing one or more of the inventive concepts disclosed herein. However, it will be apparent, however, that various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and apparatuses are shown in block diagram form to avoid unnecessarily obscuring various exemplary embodiments. Furthermore, various exemplary embodiments may be different, but are not necessarily exclusive. For example, a particular shape, configuration, and characteristic of an exemplary embodiment may be used or implemented in another exemplary embodiment without departing from the inventive concept.

[0046] Unless otherwise stated, the exemplary embodiments shown should be understood as exemplary features providing different details of some ways in which the inventive concept can be implemented in practice. Therefore, unless otherwise stated, features, components, modules, layers, films, panels, areas and / or aspects of various embodiments (hereinafter individually or collectively referred to as “elements”) may be combined, separated, interchanged and / or rearranged in other ways without departing from the inventive concept.

[0047] Crosshairs and / or shading are typically provided in the accompanying drawings to clarify the boundaries between adjacent elements. Thus, unless explicitly stated, the presence or absence of crosshairs or shading does not convey or indicate any preference or requirement for a particular material, material properties, size, scale, commonalities between the elements shown, or any other characteristics, properties, etc., of the elements. Additionally, in the drawings, the dimensions and relative dimensions of elements may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, the specific process sequence may be performed differently than the described sequence. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, similar reference numerals denote similar elements.

[0048] When an element or layer is referred to as being “on,” “connected to,” or “linked to” another element or layer, the element or layer may be directly on, directly connected to, or directly linked to the other element or layer, or an intermediary element or layer may be present. However, when an element or layer is referred to as being “directly” on, directly connected to, or directly linked to another element or layer, an intermediary element or layer is not present. Therefore, the term “connection” may indicate a physical, electrical, and / or fluid connection, with or without an intermediary element. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be interpreted as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for example, XYZ, XYY, YZ, and ZZ. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0049] Although the terms “first,” “second,” etc., may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another. Therefore, without departing from the teachings of this disclosure, the first element discussed below may be referred to as the second element.

[0050] Spatial relative terms, such as “beneath,” “below,” “under,” “lower,” “above,” “upper,” “over,” “higher,” and “side” (e.g., as in “sidewall”), may be used herein for descriptive purposes and thereby to describe the relationship of one element(s) to another(s) as shown in the accompanying drawings. In addition to the orientations depicted in the drawings, spatial relative terms are also intended to cover different orientations of the device in use, operation, and / or manufacture. For example, if the device in the drawings is flipped, an element described as “below” or “under” other elements or features will subsequently be oriented “above” other elements or features. Thus, the exemplary term “below” can cover both above and below orientations. Furthermore, the device may be oriented in other ways (e.g., rotated 90 degrees or oriented in other orientations), and thereby the spatial relative descriptive terms used herein shall be interpreted accordingly.

[0051] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” as used herein are intended to include the plural forms as well. Furthermore, the terms “comprise,” “comprising,” “include,” and / or “including”, when used in this specification, indicate the presence of stated features, integers, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, and are thus used to explain the inherent deviations in measurements, calculated values, and / or provided values ​​that would be recognized by those skilled in the art.

[0052] As is customary in the art, functional blocks, units, and / or modules are described, and some exemplary embodiments are illustrated in the accompanying drawings. Those skilled in the art will understand that these blocks, units, and / or modules are physically implemented by electronic (or optical) circuitry such as logic circuits, discrete components, microprocessors, hardwired circuits, memory elements, wiring connections, etc., which can be formed using semiconductor-based fabrication techniques or other manufacturing techniques. Where blocks, units, and / or modules are implemented by microprocessors or other similar hardware, they can be programmed and controlled using software (e.g., microcode) to perform the various functions discussed herein, and optionally, they can be driven by firmware and / or software. Furthermore, it is contemplated that each block, unit, and / or module may be implemented by dedicated hardware, or may be implemented as a combination of dedicated hardware performing certain functions and processors performing other functions (e.g., one or more programmed microprocessors and associated circuitry). Additionally, each block, unit, and / or module of some exemplary embodiments may be physically separated into two or more interactive and discrete blocks, units, and / or modules without departing from the scope of the inventive concept. Furthermore, some exemplary embodiments of blocks, units, and / or modules may be physically combined into more complex blocks, units, and / or modules without departing from the scope of the inventive concept.

[0053] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure is a part. Terms such as those defined in common dictionaries shall be interpreted as having a meaning consistent with their meaning in the context of the relevant field, and shall not be interpreted in an ideal or overly rigid sense unless expressly defined herein.

[0054] In the following, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are used for the same constituent elements in the drawings, and repeated descriptions of the same constituent elements are omitted.

[0055] Figure 1 A schematic diagram of a display device according to an embodiment of the present invention is shown, and Figure 2 It shows Figure 1 A schematic diagram of an example of a pixel unit of a display device.

[0056] Reference Figure 1 and Figure 2 The display device 1000 may include a display panel 10 containing pixel units 100.

[0057] The display panel 10 may include a display area DA and a non-display area NDA. Pixels PX1 and PX2 may be arranged in the display area DA, and various drivers for driving pixels PX1 and PX2 may be arranged in the non-display area NDA.

[0058] The display area DA may correspond to a pixel unit 100 comprising multiple pixels PX1 and PX2. The pixel unit 100 may include a first pixel area PA1 and a second pixel area PA2. The first pixel PX1 may be arranged in the first pixel area PA1, and the second pixel PX2 may be arranged in the second pixel area PA2.

[0059] In this implementation, the first pixel PX1 and the second pixel PX2 may have the same structure and may include transistors of substantially the same size. However, this is just an example, and the size of the driving transistor included in the first pixel PX1 (e.g., the ratio of channel width to channel length) may be different from the size of the driving transistor included in the second pixel PX2 (e.g., the ratio of channel width to channel length).

[0060] In the implementation method, such as Figure 2 As shown, the number (density) of first pixels PX1 arranged per unit area UA can be less than the number (density) of second pixels PX2 arranged per unit area UA. For example, when one first pixel PX1 is arranged in a unit area UA, four second pixels PX2 may be included in the unit area UA. Therefore, the resolution of the first pixel region PA1 can be lower than the resolution of the second pixel region PA2.

[0061] Because the aperture ratio (and transmittance of external light) of the first pixel region PA1 is higher than that of the second pixel region PA2, the camera, optical sensor, and the like can be arranged to overlap with the first pixel region PA1. The optical sensor may include biometric sensors, such as fingerprint sensors, iris recognition sensors, or artery sensors. However, this is just an example, and the optical sensor in the optical sensing method may also include, but is not limited to, gesture sensors, motion sensors, proximity sensors, illuminance sensors, and image sensors.

[0062] When the first pixel PX1 and the second pixel PX2 emit light based on the same data signal, the emitted brightness will differ due to the aforementioned difference in resolution. For example, when the first pixel PX1 and the second pixel PX2 emit light based on image data used to display a brightness of 1000 nits, the brightness of the first pixel region PA1 may be approximately 1 / 4 of the brightness of the second pixel region PA2. Accordingly, a brightness difference between the first pixel region PA1 and the second pixel region PA2 can be observed during high-brightness emission.

[0063] The driving current for the first pixel PX1 can be greater than the driving current for the second pixel PX2 in order to reduce the brightness difference between areas when displaying such high brightness (e.g., approximately 700 nits or greater). For example, the driving current can be increased by designing the channel width of the driving transistor for the first pixel PX1 to be greater than the channel width of the driving transistor for the second pixel PX2. However, due to limitations in the manufacturing process of the driving transistors included in the pixels, limitations in the characteristics of the driving transistors, and differences in their dispersion, it is difficult to achieve stable high brightness in the first pixel region PA1.

[0064] Furthermore, even if the gate-source voltage of the driving transistor is increased to increase the driving current, there is a limitation on how much the driving current can be increased due to the inherent voltage-current characteristics of the transistor (i.e., the relationship between the gate-source voltage and the leakage current). In this case, the grayscale (and brightness) corresponding to the data signal (i.e., the gamma voltage) cannot be output, and the gamma characteristics that can be displayed in the second pixel area PA2 (e.g., the brightness according to the gamma curve in 2.2) cannot be achieved in the high brightness and high grayscale areas.

[0065] For example, when driving at high brightness and high grayscale, the same drive current is generated for all grayscales at a predetermined grayscale or higher, and the possibility of characteristic changes and operational errors increases depending on the stress applied to the drive transistor. That is, when considering the limitation of the drive transistor's drive current, it is unnecessary to supply the data signal that generates the necessary gate-source voltage or a larger gate-source voltage to the drive transistor.

[0066] For a first pixel region PA1 that does not display high brightness as in the second pixel region PA2, a method of preemptively preventing the driving of the high-brightness region to prevent and minimize stress and operational errors of the driving transistor can be applied to the display device 1000 according to an embodiment of the present invention. Accordingly, when driven at high brightness, such as in a high-brightness mode (HBM), the grayscale and gamma voltage of the image data corresponding to the first pixel region PA1 can be controlled at a predetermined reference or less. That is, a data signal corresponding to a value less than or equal to the predetermined grayscale is supplied to the first pixel region PA1, so the gamma characteristics of the output of the first pixel region PA1 can be undistorted, and the driving transistor can operate relatively stably.

[0067] Figure 3 A block diagram of a display device according to an embodiment of the present invention is shown.

[0068] Reference Figures 1 to 3 The display device 1000 may include a pixel unit 100, a scan driver 200, a transmit driver 300, a data driver 400, a timing controller 500, and an image data corrector 600.

[0069] Pixel unit 100 may include scan lines S1 to Sn, emission control lines E1 to En, data lines D1 to Dm, and pixels PX connected to scan lines S1 to Sn, emission control lines E1 to En, and data lines D1 to Dm (here, m and n are integers greater than 1). Each of the pixels PX may include a driving transistor and a plurality of switching transistors. In an embodiment, pixel unit 100 may include the above-mentioned references. Figure 1 and Figure 2 The description includes a first pixel region PA1 and a second pixel region PA2. The first pixel region PA1 may include a first pixel PX1, and the second pixel region PA2 may include a second pixel PX2. The first pixel PX1 and the second pixel PX2 may have substantially the same structure or different structures.

[0070] The timing controller 500 can generate a first control signal SCS, a second control signal ECS, and a third control signal DCS in response to a synchronization signal supplied from an external source. The first control signal SCS can be supplied to the scan driver 200, the second control signal ECS can be supplied to the transmit driver 300, and the third control signal DCS can be supplied to the data driver 400. Additionally, the timing controller 500 can rearrange the externally supplied image data IDATA and / or corrected image data (e.g., corrected first image data CDATA) to supply the rearranged image data signal RGB to the data driver 400.

[0071] The scan driver 200 may receive a first control signal SCS from the timing controller 500 and supply scan signals to scan lines S1 to Sn based on the first control signal SCS. For example, the scan driver 200 may sequentially supply scan signals to scan lines S1 to Sn.

[0072] The transistor included in the pixel PX and receiving the scan signal can be turned on in response to the gate conduction level of the scan signal.

[0073] The transmit driver 300 can receive a second control signal ECS from the timing controller 500 and supply transmit control signals to transmit control lines E1 to En based on the second control signal ECS. For example, the transmit driver 300 can sequentially supply transmit control signals to transmit control lines E1 to En.

[0074] The transistor included in pixel PX and receiving the transmit control signal can be turned on in response to the gate on level of the transmit control signal. The transmit control signal is used to control the transmit time of pixel PX. For this purpose, the gate off period of the transmit control signal can be set to be longer than the gate on period of the scan signal.

[0075] The scan driver 200 and the emitter driver 300 can be mounted on the substrate using a thin-film process. Alternatively, the scan driver 200 can be arranged on either side of the pixel unit 100, which is located therebetween. Similarly, the emitter driver 300 can also be arranged on either side of the pixel unit 100, which is located therebetween.

[0076] In addition, although in Figure 3 The diagram shows a scan driver 200 and a transmit driver 300 supplying a scan signal and a transmit control signal, respectively, but the invention is not limited thereto. For example, the scan signal and the transmit control signal may be supplied by a single driver.

[0077] The data driver 400 receives a third control signal DCS and an image data signal RGB from the timing controller 500. The data driver 400 converts the image data signal RGB into an analog data signal. In response to the third control signal DCS, the data driver 400 supplies data signals to data lines D1 to Dm. The data signals can be supplied to the pixel PX selected by the scan signal.

[0078] At the same time, despite Figure 3 The diagram shows n scan lines S1 to Sn and n emission control lines E1 to En, but the invention is not limited thereto. For example, additional dummy scan lines and / or dummy emission control lines (not shown) may be additionally formed in the pixel unit 100.

[0079] Image data corrector 600 can adjust the limit grayscale of the first image data corresponding to the first pixel region PA1 based on the dimming level. For example, image data corrector 600 can extract the first image data from image data IDATA provided by an external graphics processor or the like to correct the first image data. Here, the dimming level can be defined as the maximum brightness of light that the pixel unit 100 can emit. For example, when the dimming level is set to 1000 nits, the pixel unit 100 can emit up to 1000 nits of light. When the dimming level is set to 100 nits, the pixel unit 100 can emit up to 100 nits of light. The maximum brightness (dimming level) can be controlled by the correction of the gamma voltage corresponding to the image data and / or the width control of the emission control signal.

[0080] Image data corrector 600 can correct the first image data based on limit grayscale. The corrected first image data CDATA can be provided to timing controller 500. The second image data corresponding to the second pixel region PA2 can be supplied to timing controller 500 without correction by image data corrector 600.

[0081] The timing controller 500 can rearrange the corrected first image data CDATA and second image data to provide them to the data driver 400.

[0082] In one implementation, the image data corrector 600 can enhance a predetermined input grayscale value that is less than or equal to a limit grayscale value. Correspondingly, the emission brightness of low grayscale values ​​can be increased.

[0083] In an embodiment, the display device 1000 may further include a power supply unit that supplies driving power supplies VDD and VSS for driving pixels PX to the pixel unit 100.

[0084] At the same time, despite Figure 3 The data driver 400, timing controller 500, and image data corrector 600 are shown as separate configurations; however, at least some of the functions of the data driver 400, timing controller 500, and image data corrector 600 can be integrated as integrated circuits (ICs). Additionally, the display device 1000 may include a compensation block for compensating for pixel degradation and / or image ghosting, as well as IR voltage drop of the data signal. The compensation block can process the corrected first image data CDATA output from the image data corrector 600 to provide it to the timing controller 500.

[0085] In the following text, reference will be made to Figures 4 to 9C The configuration and functions of the image data corrector 600 are described.

[0086] Figure 4 It shows that it includes Figure 3 A block diagram of an example image data corrector in a display device.

[0087] Reference Figure 1 , Figure 2 and Figure 4 The image data corrector 600 may include a limit grayscale controller 620, a grayscale mapper 640, and a lookup table (LUT) 650.

[0088] The limit grayscale controller 620 can determine the limit grayscale LG for the first image data IDATA1 based on the ratio between the dimming level DIM and a preset reference brightness RL. In an embodiment, the reference brightness RL can be the brightness of the first pixel region PA1 when the first pixel PX1 emits light with the maximum driving current that can be generated in the first pixel PX1. That is, the reference brightness RL can be the maximum brightness that can be displayed in the first pixel region PA1.

[0089] The reference brightness RL can be determined experimentally during the manufacturing process and can be stored in the memory of the display device 1000. For example, the reference brightness RL can be set to 500 nits.

[0090] The limit grayscale controller 620 can calculate the ratio between the dimming level DIM and the reference brightness RL. In this case, when the dimming level DIM is equal to or lower than the reference brightness RL, the operation of setting the limit grayscale LG by the image data corrector 600 and the correction of the first image data IDATA1 are not performed. Since the first pixel area PA1 can emit light at the brightness corresponding to the dimming level DIM, it is not necessary to set the limit grayscale.

[0091] The grayscale limit LG can be the maximum grayscale applied to the first pixel area PA1. For example, when the grayscale of the display device 1000 is displayed in 8 bits, the image data can be represented from grayscale 0 to grayscale 255. When the grayscale limit LG is 200 grayscale, the maximum grayscale value of the first pixel area PA1 supplied to the data driver 400 can be 200 grayscale.

[0092] In this implementation, the grayscale value of an input grayscale that is greater than or equal to a grayscale limit LG can be converted, and the output grayscale value can be less than or equal to the grayscale limit LG. For example, when the input grayscale value is in the range of 200 grayscale to 255 grayscale, the corresponding output grayscale value can be 200 grayscale or less.

[0093] Accordingly, for the same input gray level greater than or equal to the gray level limit LG, the voltage of the data signal supplied to the first pixel PX1 may differ from the voltage of the data signal supplied to the second pixel PX2. For example, when pixels PX1 and PX2 include p-channel driving transistors and the input gray level is 250, the voltage of the data signal supplied to the first pixel PX1 may be greater than the voltage of the data signal supplied to the second pixel PX2. Conversely, when pixels PX1 and PX2 include n-channel driving transistors and the input gray level is 250, the voltage of the data signal supplied to the first pixel PX1 may be less than the voltage of the data signal supplied to the second pixel PX2. Therefore, during high brightness and high gray level emission, the brightness of the second pixel PX2 may be higher than the brightness of the first pixel PX1.

[0094] When the reference luminance RL is 500 nits and the dimming level DIM is 1000 nits, the ratio between the dimming level DIM and the reference luminance RL can be determined to be 0.5. That is, the first pixel region PA1 can emit up to 50% of the light at the dimming level DIM. In this case, the limit grayscale LG can be calculated by the relationship between luminance and digital grayscale value, and can be represented by Equation 1 below.

[0095] [Equation 1]

[0096] (LG) gamma =A*(MG) gamma

[0097] Here, LG is the limit gray level, A is the ratio between the dimming level DIM and the reference brightness RL, MG is the maximum gray level applied to the display device 1000, and gamma is the gamma constant applied to the gamma conversion of the image data. For example, when applying a gamma 2.2 curve, gamma can be 2.2.

[0098] (LG) gamma It can represent the brightness at the limit gray level LG, and (MG) gamma This can represent the brightness at maximum grayscale. Accordingly, the relationship in Equation 1 can be established based on the ratio A between the dimming level DIM and the reference brightness RL.

[0099] According to Equation 1, the limit gray level LG can be calculated as shown in Equation 2.

[0100] [Equation 2]

[0101] LG = (A) 1 / gamma *MG

[0102] In this case, the ratio A between the dimming level DIM and the reference brightness RL can be less than 1. For example, when the ratio A between the dimming level DIM and the reference brightness RL is 0.5 and the gamma value is 2.2, the limit gray level LG can be calculated as 186 gray levels, which is an approximation of the result of Equation 2.

[0103] Accordingly, the grayscale range of the corrected first image data CDATA can be smaller than the grayscale range of the second image data, which does not reflect the correction.

[0104] Meanwhile, as the dimming level DIM increases, the limit grayscale LG can decrease according to the constraint of Equation 2. That is, the limit grayscale LG can be adjusted according to the change in the dimming level DIM.

[0105] In one implementation, the limit grayscale LG can be set the same for red / blue / green pixels. In another implementation, the limit grayscale LG for red / blue / green pixels can be set using different methods and at different values ​​to prevent color distortion.

[0106] Grayscale mapper 640 can generate an output grayscale based on a limit grayscale LG, wherein the input grayscale of the first image data IDATA1 has been converted. The first image data IDATA1 can be converted by grayscale mapper 640 into corrected first image data CDATA.

[0107] In one implementation, the grayscale mapper 640 can convert input grayscale to output grayscale using a lookup table 650. The lookup table 650 stores the relationship between input grayscale and output grayscale based on a dimming level (DIM) or a limit grayscale (LG). For example, the lookup table 650 may include a formula or table in which the output grayscale increases non-linearly with increasing input grayscale. Alternatively, the lookup table 650 may include multiple lookup tables containing different types of formulas or tables based on the dimming level (DIM) or the limit grayscale (LG).

[0108] The grayscale converted by the grayscale mapper 640 can be output as corrected first image data CDATA. The corrected first image data CDATA can be provided to the timing controller 500 or the data driver 400.

[0109] Figures 5A to 5C It shows from Figure 4 A graph showing an example of the corrected first image data output by the image data corrector.

[0110] Reference Figures 2 to 5C The grayscale limit LG can vary depending on the dimming level DIM.

[0111] Figures 5A to 5C An example is shown where the grayscale mapper 640 of the image data corrector 600 linearly maps the input grayscale IN and the output grayscale OUT. For example, the input grayscale IN and the output grayscale OUT can be the same for grayscale values ​​less than or equal to a first limit grayscale LG1, a second limit grayscale LG2, and a third limit grayscale LG3.

[0112] like Figure 5A As shown, in the brightness (or luminance) mode with the first dimming level DIM1 applied, a first limit gray level LG1 can be determined. When the image data corrector 600 is not operating, the input gray level IN can be output as the output gray level OUT. For example, when the input gray level IN is 255 gray level, the output gray level OUT can be 255 gray level.

[0113] The first gray level G1 and the first limit gray level LG1 can be the same gray level. When the input gray level IN is greater than or equal to the first gray level G1, the corresponding output gray level OUT can be output as the first limit gray level LG1.

[0114] like Figure 5B As shown, in the brightness mode applying the second dimming level DIM2, the second grayscale G2 can be determined as the second limit grayscale LG2. In an embodiment, the maximum brightness of the first dimming level DIM1 can be greater than the maximum brightness of the second dimming level DIM2. For example, the maximum brightness of the first dimming level DIM1 can be approximately 2000 nits, and the maximum brightness of the second dimming level DIM2 can be approximately 1500 nits.

[0115] In this case, according to Equation 2, the second limit gray level LG2 can have a larger value than the first limit gray level LG1. Accordingly, the gray level range between the second limit gray level LG2 and the highest gray level in the second dimming level DIM2 can be smaller than the gray level range between the first limit gray level LG1 and the highest gray level in the first dimming level DIM1.

[0116] The grayscale range of the corrected first image data CDATA corresponding to the first dimming level DIM1 can be between 0 grayscale and the first grayscale G1, and the grayscale range of the corrected first image data CDATA corresponding to the second dimming level DIM2 can be between 0 grayscale and the second grayscale G2. Accordingly, the grayscale range of the corrected first image data CDATA corresponding to the first dimming level DIM1 can be smaller than the grayscale range of the corrected first image data CDATA corresponding to the second dimming level DIM2.

[0117] like Figure 5C As shown, in the brightness mode applying the third dimming level DIM3, the third grayscale G3 can be determined as the third limit grayscale LG3. In an embodiment, the maximum brightness of the second dimming level DIM2 can be greater than the maximum brightness of the third dimming level DIM3. For example, the maximum brightness of the third dimming level DIM3 can be approximately 1000 nits.

[0118] In the following description, the corresponding maximum brightness of the first dimming level DIM1, the second dimming level DIM2, and the third dimming level DIM3 will be described under the assumption that they are 2000 nits, 1500 nits, and 1000 nits. Additionally, a reference brightness RL of 500 nits is assumed. However, this is for illustrative purposes only, and this setting is used to explain the relative differences between the first dimming level DIM1, the second dimming level DIM2, and the third dimming level DIM3 and the reference brightness RL; the maximum brightness and the reference brightness RL are not limited to these.

[0119] Therefore, the first limit gray level LG1, the second limit gray level LG2, and the third limit gray level LG3 can be determined based on the ratio between the maximum brightness of the dimming level and the reference brightness RL, as well as Equation 2. Thus, high brightness and high gray level driving that cannot be achieved in the first pixel region PA1 can be prevented in advance through image data correction. Accordingly, data signals corresponding to unnecessary gray level values ​​can be withheld from the first pixel region PA1, the gamma characteristics of the output of the first pixel region PA1 can remain undistorted, and the driving transistor of the first pixel PX1 can operate relatively stably.

[0120] Figures 6A to 6C It shows from Figure 4 A graph of another example of the corrected first image data output by the image data corrector.

[0121] Reference Figures 2 to 6C The grayscale mapper 640 can non-linearly map the input grayscale IN and output grayscale OUT of the first image data IDATA1 based on the first limit grayscale LG1, the second limit grayscale LG2 and the third limit grayscale LG3.

[0122] like Figure 5A As shown, all input gray levels IN that are greater than or equal to the first gray level G1 can be output as the first limit gray level LG1 (i.e., the first gray level G1). Accordingly, high gray levels that are greater than or equal to the first gray level G1 can be displayed as blocks of the first gray level G1, leading to image quality degradation.

[0123] The grayscale mapper 640 can non-linearly set the relationship between the input grayscale IN and the output grayscale OUT, so that the output grayscale OUT can be smoothly changed and output relative to all input grayscale IN. For example, as Figure 6A As shown, the input / output relationship of grayscale can be reset by grayscale mapper 640 so that the input grayscale IN and the output grayscale OUT can correspond one-to-one with each other. In this case, the output grayscale OUT can be set to no more than a first limit grayscale LG1.

[0124] Through the operation of grayscale mapper 640 Figure 5B and Figure 5C The relationship between the input grayscale IN and the output grayscale OUT can be corrected as follows: Figure 6B and Figure 6C The nonlinear relationship shown.

[0125] Therefore, the image quality in high grayscale areas can be improved through the operation of grayscale mapper 640.

[0126] Figure 7 It shows that it includes Figure 3 A block diagram of another example of an image data corrector in a display device.

[0127] exist Figure 7 In the figures, the same reference numerals are used for reference above. Figure 4 The same or similar elements will be described, and redundant descriptions will be omitted.

[0128] Reference Figure 1 , Figure 2 and Figure 7 The image data corrector 600A may include a limit grayscale controller 620, a grayscale mapper 640A, a lookup table (LUT) 650A, and a grayscale enhancer 660.

[0129] The information of the limit grayscale LG generated by the limit grayscale controller 620 can be provided to the grayscale enhancer 660 and the grayscale mapper 640A.

[0130] The grayscale enhancer 660 can enhance a first grayscale range (e.g., based on the ratio between the reference brightness RL and the dimming level DIM) Figure 8A The input grayscale value IN of GR1. The first grayscale range may include input grayscale values ​​less than the grayscale limit LG. In other words, input grayscale values ​​less than the grayscale limit LG (e.g., low grayscale values) may be converted to grayscale values ​​greater than the input grayscale value for output.

[0131] For those included in the first grayscale range ( Figure 8A For the same input grayscale IN in GR1), the brightness of the first pixel PX1 can be greater than the brightness of the second pixel PX2. However, since the resolution of the first pixel region PA1 is lower than the resolution of the second pixel region PA2, when the entire pixel unit 100 is observed, the brightness of the first pixel region PA1 can be similar to the brightness of the second pixel region PA2.

[0132] For ease of description, reference will be made in the following text. Figure 8A The function of grayscale enhancer 660 is described.

[0133] The grayscale enhancer 660 determines the enhancement ratio BR by using the ratio between the reference brightness RL and the dimming level DIM. The enhancement ratio BR can be a ratio relative to the input grayscale (...). Figure 8A (IN) enhances output grayscale ( Figure 8A The multiple (or parameter) of OUT in the equation. In this embodiment, as in Equation 1, since brightness can be determined by (grayscale)... gamma Therefore, the enhancement ratio BR can be calculated using Equations 3 and 4 below.

[0134] [Equation 3]

[0135]

[0136] Here, DIM_L is the maximum brightness value corresponding to the dimming level DIM, RL_L is the brightness value of the reference brightness RL, and L_ratio is the brightness ratio that represents the ratio of the reference brightness RL to the maximum brightness value. I_G is the input gray level IN, O_G is the output gray level OUT corresponding to the input gray level IN, and gamma is the gamma constant applied to the gamma conversion of the image data. Accordingly, the enhancement ratio BR, corresponding to the ratio of the output gray level OUT to the input gray level IN, can be calculated using Equation 4 below.

[0137] [Equation 4]

[0138]

[0139] For example, when the luminance ratio L_ratio is 2 and 2.2 gamma is applied, the enhancement ratio BR can be determined to be approximately 1.37. That is, the output gray level OUT corresponding to the input gray level IN of the first gray level range GR1 can have a gray level value that is approximately 1.37 times that of the input gray level IN. As described above, in a predetermined low gray level range under the same dimming level conditions, the output gray level OUT with an enhancement ratio BR greater than 1 applied to the input gray level IN can be greater than the output gray level OUT without an enhancement ratio BR applied. An input gray level IN that is less than the limit gray level LG (e.g., a low gray level) can be converted to a gray level value greater than the input gray level IN for output.

[0140] Furthermore, according to Equation 4, the smaller the luminance ratio L_ratio, the smaller the enhancement ratio BR can be. That is, as the maximum luminance caused by the dimming level DIM decreases, the enhancement ratio BR can decrease.

[0141] In one implementation, grayscale enhancer 660 may use the enhancement ratio BR to determine a first grayscale range GR1 to which grayscale enhancement has been applied. Grayscale enhancer 660 may determine the maximum enhanced grayscale MBG, which is the maximum value of the input grayscale to which grayscale enhancement has been applied.

[0142] The maximum enhanced gray level (MBG) can be determined by the enhancement ratio (BR) and the limit gray level (LG). For example, the maximum enhanced gray level (MBG) can be calculated based on the value obtained by dividing the limit gray level (LG) by the enhancement ratio (BR) (i.e., it can be represented by LG / BR), and it is in... Figure 8A The middle part is represented as G1'.

[0143] For example, when the enhancement ratio BR is 1.2 and the limit gray level LG is 200 gray levels, the maximum enhancement gray level MBG can be determined to be 166 gray levels. In this case, the enhancement ratio BR can be multiplied by the input gray level of 166 gray levels or less, and the input gray level of more than 166 gray levels can be output as 200 gray levels as the limit gray level LG.

[0144] When data signals are generated for the first pixel PX1 and the second pixel PX2 after the input grayscale IN included in the first grayscale range GR1 is corrected by the image data corrector 600A, the first data signal supplied to the first pixel PX1 may be different from the second data signal supplied to the second pixel PX2. For example, when the driving transistor of each of the first pixel PX1 and the second pixel PX2 is a p-channel driving transistor, the first data signal may be less than the second data signal. When the driving transistor of each of the first pixel PX1 and the second pixel PX2 is an n-channel driving transistor, the first data signal may be greater than the second data signal.

[0145] Therefore, the driving current in the first pixel PX1 can be greater than the driving current in the second pixel PX2, and the brightness of the first pixel PX1 can be greater than the brightness of the second pixel PX2. Correspondingly, when displaying an image in a low grayscale area, the brightness of the first pixel area PA1 and the brightness of the second pixel area PA2 can be similar.

[0146] Meanwhile, when a data signal is generated based on an input gray level IN that is greater than or equal to the limit gray level LG, the driving current caused by the third data signal supplied to the first pixel PX1 can be less than the driving current caused by the fourth data signal supplied to the second pixel PX2.

[0147] For example, when the driving transistors of each of the first pixel PX1 and the second pixel PX2 are p-channel driving transistors, the third data signal can be greater than the fourth data signal. When the driving transistors of each of the first pixel PX1 and the second pixel PX2 are n-channel driving transistors, the third data signal can be less than the fourth data signal.

[0148] Therefore, high brightness and high grayscale driving that cannot be achieved in the first pixel region PA1 can be prevented in advance through image data correction. Accordingly, data signals corresponding to unnecessary grayscale values ​​are not supplied to the first pixel region PA1.

[0149] In one embodiment, the image data corrector 600A may further include a grayscale mapper 640A. The grayscale mapper 640A can generate an output grayscale value based on a limit grayscale LG, wherein the input grayscale value of the first image data IDATA1 has been converted. The first image data IDATA1 can be converted into corrected first image data CDATA by the grayscale mapper 640A.

[0150] In an implementation, grayscale mapper 640A can convert input grayscale to output grayscale using lookup table 650A. For example, lookup table 650A may include a formula or table in which the output grayscale increases non-linearly with increasing input grayscale. (Due to reference...) Figure 4 The functionality of the grayscale mapper 640A has been described in detail, so repeated descriptions will be omitted.

[0151] Figures 8A to 8C It shows from Figure 7 A graph showing an example of the corrected first image data output by the image data corrector.

[0152] Reference Figure 2 , Figure 3 , Figure 7 , Figure 8A , Figure 8B and Figure 8CThe maximum brightness of the gray level LG and the enhancement ratio BR can vary depending on the dimming level DIM. The maximum brightness of the first dimming level DIM1 is greater than the maximum brightness of the second dimming level DIM2, and the maximum brightness of the second dimming level DIM2 is greater than the maximum brightness of the third dimming level DIM3.

[0153] Figures 8A to 8C An example is shown of enhancing the input grayscale IN, which includes a first grayscale range GR1, a second grayscale range GR2, and a third grayscale range GR3, using a grayscale enhancer 660.

[0154] like Figure 8A As shown, in the brightness mode applying the first dimming level DIM1, the first limit grayscale LG1 can be determined by the limit grayscale controller 620. (See reference...) Figure 7 As described, the grayscale intensifier 660 can determine the enhancement ratio BR and the maximum enhanced grayscale MBG (G1').

[0155] Input grayscale values ​​IN, including those in the first grayscale range GR1, can be enhanced and output based on the enhancement ratio BR. Input grayscale values ​​IN greater than the maximum enhanced grayscale value G1' can be output as the first limit grayscale value LG1.

[0156] like Figure 8B As shown, in the brightness mode applying the second dimming level DIM2, the second limit gray level LG2, which is greater than the first limit gray level LG1, can be set using Equation 2. Furthermore, the enhancement ratio BR can be calculated using Equation 4. Since the enhancement ratio BR in the brightness mode with the relatively low brightness ratio of the second dimming level DIM2 is less than that according to... Figure 8A The enhancement ratio of BR, therefore Figure 8B The slope of the curve for the second grayscale range GR2 can be less than... Figure 8A The slope of the curve for the first grayscale range GR1. Input grayscale IN included in the second grayscale range GR2 can be enhanced and output. Input grayscale IN greater than the maximum enhanced grayscale G2' can be output as the second limit grayscale LG2.

[0157] like Figure 8C As shown, in the brightness mode applying the third dimming level DIM3, a third grayscale limit LG3 can be set that is greater than the second grayscale limit LG2. Additionally, values ​​less than [the second grayscale limit LG2] can be calculated using Equation 4. Figure 8B The derived enhancement ratio BR is the enhancement ratio of BR. Therefore, Figure 8C The slope of the curve for the third grayscale range GR3 can be less than... Figure 8B The slope of the curve for the second grayscale range GR2. Input grayscale IN included in the third grayscale range GR3 can be enhanced and output. Input grayscale IN greater than the maximum enhanced grayscale G3' can be output as the third limit grayscale LG3.

[0158] As described above, input gray levels IN that are less than or equal to the maximum enhanced gray levels MBG, G1', G2', and G3' can be enhanced at different ratios according to the dimming level DIM, so that the image data of the first pixel region PA1 can be corrected. Accordingly, the brightness of the first pixel region PA1 relative to the input gray levels IN that are less than or equal to intermediate gray levels can be increased. Consequently, when the image is displayed based on input image data with intermediate gray levels (e.g., approximately 100 gray levels) or lower, the brightness difference between the first pixel region PA1 and the second pixel region PA2, which have different resolutions, can be minimized.

[0159] Figures 9A to 9C It shows from Figure 7 A graph of another example of the corrected first image data output by the image data corrector.

[0160] Reference Figures 7 to 9C The grayscale mapper 640A can nonlinearly map the input grayscale IN and output grayscale OUT of the first image data IDATA1 based on the first limit grayscale LG1, the second limit grayscale LG2 and the third limit grayscale LG3.

[0161] The grayscale mapper 640A can non-linearly set the relationship between input grayscale values ​​IN and output grayscale values ​​OUT, so that the output grayscale value OUT can be smoothly changed and output relative to all input grayscale values ​​IN. For example, the input / output relationship of grayscale values ​​can be reset by the grayscale mapper 640A so that the input grayscale values ​​IN and output grayscale values ​​OUT can correspond one-to-one with each other. In this case, the output grayscale value OUT can be set to not exceed a first limit grayscale value LG1.

[0162] Through the operation of the grayscale mapper 640A Figures 8A to 8C The relationship between the input grayscale IN and the output grayscale OUT can be corrected as follows: Figures 9A to 9C The nonlinear relationship shown is illustrated. Therefore, through the operation of the grayscale mapper 640A, grayscale aggregation in high grayscale regions can be minimized, and image quality can be improved.

[0163] As described above, the image data corrector and the display device including the image data corrector according to embodiments of the present invention can adaptively limit the grayscale and gamma voltage of image data corresponding to a first pixel region having a relatively low pixel density based on the dimming level. Therefore, high brightness and high grayscale driving that cannot be achieved in the first pixel region can be prevented in advance by image data correction. Accordingly, data signals corresponding to unnecessary grayscale values ​​may not be supplied to the first pixel region, the gamma characteristics of the output of the first pixel region may not be distorted, and the driving transistor of the first pixel may operate relatively stably.

[0164] Furthermore, the image data corrector according to embodiments of the present invention and the display device including the image data corrector can adaptively enhance gray levels other than a limited input gray level according to the dimming level. Therefore, the brightness of the first pixel region relative to an input gray level of intermediate or lower gray levels can be increased. Accordingly, when an image is displayed based on input image data of intermediate gray levels (e.g., approximately 100 gray levels) or lower gray levels, the brightness difference between the first pixel region and the second pixel region with different resolutions can be minimized.

[0165] While certain exemplary embodiments and implementations have been described herein, other embodiments and variations will become apparent from this description. Accordingly, as will be apparent to those skilled in the art, the inventive concept is not limited to these embodiments, but is limited to the broader scope of the appended claims and various obvious variations and equivalent arrangements.

Claims

1. A display device, comprising: A pixel unit, the pixel unit comprising a first pixel arranged in a first pixel region and a second pixel arranged in a second pixel region; An image data corrector is configured to adjust a limit grayscale of first image data corresponding to the first pixel region based on a dimming level that limits the maximum brightness of light emitted by the pixel unit, and to correct the first image data based on the limit grayscale. A data driver configured to supply a data signal to the pixel unit based on corrected first image data and second image data corresponding to the second pixel region; as well as A scan driver configured to supply a scan signal to the pixel unit, and The number of first pixels arranged per unit area is less than the number of second pixels arranged per unit area.

2. The display device as claimed in claim 1, wherein, The image data corrector includes: A limit grayscale controller is configured to determine the limit grayscale of the first image data based on the ratio between the dimming level and a preset reference brightness. The reference brightness is the brightness of the first pixel region when the first pixel emits light through the maximum driving current that can be generated in the first pixel.

3. The display device as claimed in claim 2, wherein, The grayscale value is converted from an input grayscale value greater than or equal to the specified limit grayscale value, and the output grayscale value is less than or equal to the specified limit grayscale value. Wherein, for the same input gray level that is greater than or equal to the limit gray level, the voltage of the data signal supplied to the first pixel and the voltage of the data signal supplied to the second pixel are different from each other.

4. The display device as claimed in claim 2, wherein, The limit gray level corresponding to the first dimming level is less than the limit gray level corresponding to the second dimming level, and The maximum brightness of the first dimming level is greater than the maximum brightness of the second dimming level, and Wherein, the grayscale range of the corrected first image data corresponding to the first dimming level is smaller than the grayscale range of the corrected first image data corresponding to the second dimming level.

5. The display device as claimed in claim 2, wherein, The grayscale range of the corrected first image data is smaller than that of the second image data.

6. The display device as claimed in claim 2, wherein, The image data corrector also includes: A grayscale mapper configured to non-linearly map the input and output grayscale of the first image data based on the limit grayscale.

7. The display device as claimed in claim 6, wherein, The image data corrector also includes: A grayscale enhancer configured to enhance the input grayscale in a first grayscale range based on a ratio between the reference brightness and the dimming level. The first grayscale range includes the input grayscale values ​​that are smaller than the specified grayscale limit, and The grayscale enhancer is configured to determine the enhancement ratio by using the ratio between the reference brightness and the dimming level, and to determine the first grayscale range by using the enhancement ratio and the limit grayscale.

8. The display device as claimed in claim 7, wherein, The first data signal supplied to the first pixel and the second data signal supplied to the second pixel are different from the first input gray level included in the first gray level range. The third data signal supplied to the first pixel and the fourth data signal supplied to the second pixel are different from the second input gray level, which is greater than or equal to the limit gray level. When the driving transistor of each of the first pixel and the second pixel is a p-channel driving transistor, the voltage of the first data signal is less than the voltage of the second data signal, and the voltage of the third data signal is greater than the voltage of the fourth data signal.

9. The display device as claimed in claim 8, wherein, At the first dimming level, the first output grayscale corresponding to the first input grayscale is greater than the second output grayscale corresponding to the first input grayscale at the second dimming level. The maximum brightness of the first dimming level is greater than the maximum brightness of the second dimming level.

10. The display device as claimed in claim 8, wherein, The grayscale mapper is configured to non-linearly map the input grayscale and the output grayscale of the first image data based on the limit grayscale and the enhancement ratio.

Images