Brightness control unit, and display device and electronic device including same

Abstract

Disclosed are a brightness control unit and a display device and an electronic device including the same. The brightness control unit includes: a driving power voltage setting unit configured to determine a driving power voltage to be supplied to the display panel based on a plurality of driving power voltages respectively corresponding to a plurality of reference brightness of the display panel, the driving power voltage corresponding to a target brightness; and a gamma voltage setting unit configured to determine a target brightness corresponding to the target brightness based on a plurality of target brightnesses respectively corresponding to the plurality of reference brightnesses, and set a gamma voltage for achieving the target brightness, the driving power voltage and the gamma voltage are set differently with respect to the same reference brightness in accordance with ambient illuminance of the display panel.

Description

[0001] This application is a divisional application of a patent application with an application date of March 11, 2020, application number 202010165972.1, and invention name “Brightness control unit and display device including the brightness control unit”. Technical Field

[0002] Aspects of some example embodiments of the present disclosure generally relate to a brightness control unit and a display device including the brightness control unit. Background Art

[0003] The display device may display an image based on input image data. The display device may modulate the brightness of the input image data according to the average pixel level (APL) of the input image data, thereby reducing the power consumption of the display device. This may be referred to as an automatic current limiting (ACL) function.

[0004] The display device can also adjust the low potential driving power voltage according to the APL of the input image data, thereby reducing the power consumption of the display device. This may be referred to as a content adaptive power saving (CAPS) function.

[0005] In the ACL function, the brightness of the input image data is modulated according to the APL of the input image data, so that the user's desired high brightness emission requirements can be met even in high APL images. In the CAPS function, the low potential drive power voltage can be adjusted, so weak bright spots may appear.

[0006] The above information disclosed in this Background section is only for enhancement of understanding of the background technology and therefore it may contain information that does not constitute prior art. Summary of the invention

[0007] Some example embodiments provide a brightness control unit configured to determine a driving power voltage according to ambient illumination and to limit a target brightness according to the determined driving power voltage and a display device including the same.

[0008] Some example embodiments also provide a brightness control unit and a display device including the same, the brightness control unit being configured to adaptively perform brightness correction according to ambient illumination when an average pixel level (APL) is greater than a threshold, thereby reducing power consumption without image quality degradation.

[0009] According to some example embodiments of the present disclosure, a brightness control unit may include: a driving power voltage setting unit, configured to determine a driving power voltage to be provided to a display panel based on a plurality of driving power voltages respectively corresponding to a plurality of reference brightnesses of the display panel, the driving power voltage corresponding to a target brightness; and a gamma voltage setting unit, configured to determine a target brightness corresponding to the target brightness based on a plurality of target brightnesses respectively corresponding to the plurality of reference brightnesses, and to set a gamma voltage for achieving the target brightness, wherein the driving power voltage and the gamma voltage are set differently for the same reference brightness according to the ambient illumination of the display panel.

[0010] According to some example embodiments, when the ambient illuminance is less than the illuminance threshold, the maximum value of the reference luminance may be set to be smaller than the maximum reference luminance of the display panel.

[0011] According to some example embodiments, when the ambient illuminance is less than the illuminance threshold, the driving power voltage setting unit may equally set the driving power voltage to the threshold driving power voltage corresponding to a reference luminance greater than a first threshold luminance.

[0012] According to some example embodiments, the first threshold brightness may be a minimum value of reference brightness for which an abnormal output is not viewed on the display panel when the display panel is driven by the threshold driving power voltage.

[0013] According to some example embodiments, the brightness control unit may further include a brightness modulator configured to correct the gamma voltage when an average pixel level (APL) of the input image data is greater than or equal to an APL threshold.

[0014] According to some example embodiments, the brightness modulator may determine a corrected brightness for a target brightness based on the target brightness, and may correct the gamma voltage to achieve the corrected brightness.

[0015] According to some example embodiments, when the ambient illuminance is less than the illuminance threshold, the brightness modulator may equally set the correction brightness corresponding to a reference brightness greater than the first threshold brightness.

[0016] According to some example embodiments, when the ambient illuminance is less than the illuminance threshold, the brightness modulator may set the correction brightness such that a difference between the correction brightness for a maximum value of the reference brightness and the target brightness corresponds to a threshold correction offset.

[0017] According to some example embodiments of the present disclosure, a display device includes: a display panel including a plurality of pixels; a brightness control unit configured to determine a driving power voltage based on a target brightness of the display panel, and set a gamma voltage for achieving a target brightness corresponding to the target brightness; a display panel driver configured to drive the display panel based on the gamma voltage; and a power provider configured to provide the determined driving power voltage to the display panel, wherein the driving power voltage and the gamma voltage are set differently for the same reference brightness according to the ambient illumination of the display panel.

[0018] According to some example embodiments, the brightness control unit may include: a driving power voltage setting unit, configured to include a plurality of driving power voltages corresponding to a plurality of reference brightnesses, respectively, and determining a driving power voltage to be provided to the display panel based on a target brightness; and a gamma voltage setting unit, configured to include a plurality of target brightnesses corresponding to the plurality of reference brightnesses, respectively, and setting a target brightness and a gamma voltage for achieving the target brightness based on the target brightness.

[0019] According to some example embodiments, when the ambient illuminance is less than the illuminance threshold, the maximum value of the reference luminance may be set to be smaller than the maximum reference luminance of the display panel.

[0020] According to some example embodiments, when the ambient illuminance is less than the illuminance threshold, the driving power voltage setting unit may equally set the driving power voltage to the threshold driving power voltage corresponding to a reference luminance greater than a first threshold luminance.

[0021] According to some example embodiments, the brightness control unit may further include a brightness modulator configured to correct the gamma voltage when an average pixel level (APL) of the input image data is greater than or equal to an APL threshold value.

[0022] According to some example embodiments, the brightness modulator may determine a corrected brightness for a target brightness based on the target brightness, and may correct a gamma voltage to achieve the corrected brightness.

[0023] According to some example embodiments, when the ambient illuminance is less than the illuminance threshold, the brightness modulator may equally set the correction brightness corresponding to a reference brightness greater than the first threshold brightness.

[0024] According to some example embodiments, when the ambient illuminance is less than the illuminance threshold, the brightness modulator may set the correction brightness such that a difference between the correction brightness for a maximum value of the reference brightness and the target brightness corresponds to a threshold correction offset. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Various aspects of some example embodiments will now be described more fully below with reference to the accompanying drawings; however, they may be implemented in different forms and should not be construed as limited to the example embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be more thorough and complete, and these example embodiments will more fully convey the scope of the example embodiments to those skilled in the art.

[0026] In the accompanying drawings, dimensions may be exaggerated for clarity of illustration. It will be understood that when an element is referred to as being "between" two elements, the element may be the only element between the two elements, or one or more intermediate elements may also be present. The same reference numerals always refer to the same elements.

[0027] Figure 1 is a block diagram illustrating a display device according to some example embodiments of the present disclosure.

[0028] Figure 2 is a diagram showing some example embodiments Figure 1 Figure 1 shows the pixels shown in Figure 1.

[0029] Figure 3 It is shown Figure 1 A block diagram of an example of a brightness control unit is shown in FIG.

[0030] Figure 4 : is a diagram showing an example of a low potential driving power voltage corresponding to a reference brightness.

[0031] Figure 5 : is a diagram showing an example of target brightness corresponding to reference brightness.

[0032] Figure 6 : is a diagram showing an example of target brightness corresponding to reference brightness when brightness modulation is performed.

[0033] Figure 7 is a diagram showing an example in which a reference brightness, a target brightness, and a low-potential driving power voltage are set in a high-illuminance environment.

[0034] Figure 8 is a diagram showing an example in which a reference brightness, a target brightness, and a low-potential driving power voltage are set in a low-illuminance environment.

[0035] Fig. 9 It is shown Figure 1 A block diagram of an example of a brightness control unit is shown in FIG.

[0036] Fig.10 It is shown Figure 1 A block diagram of an example of a brightness control unit is shown in FIG. DETAILED DESCRIPTION

[0037] Hereinafter, various aspects of some example embodiments will be described in more detail with reference to the accompanying drawings. However, the present invention can be implemented in various different forms and should not be construed as being limited to the embodiments shown here. On the contrary, these embodiments are provided as examples so that the disclosure will be more thorough and more complete, and will more fully convey the aspects and features of the present invention to those skilled in the art. Therefore, processes, elements and techniques that are not necessary for a full understanding of the aspects and features of the present invention for those of ordinary skill in the art may not be described or shown in the accompanying drawings. Unless otherwise stated, the same reference numerals represent the same elements throughout the accompanying drawings and written descriptions, and therefore their descriptions may not be repeated. In the accompanying drawings, for clarity, the relative sizes of elements, layers and regions may be exaggerated.

[0038] It will be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the spirit and scope of the present invention, the first element, first component, first region, first layer or first part described below may be named as the second element, second component, second region, second layer or second part.

[0039] For ease of explanation, spatially relative terms such as "under", "below", "below", "below", "above", "on", etc. may be used herein to describe the relationship of one element or feature to another (multiple) element or (multiple) feature as shown in the drawings. It will be understood that spatially relative terms are intended to include different orientations of the device in use or in operation in addition to the orientation depicted in the drawings. For example, if the device in the drawings is turned over, the element described as "below" or "below" or "below" other elements or features will then be positioned as "above" the other elements or features. Therefore, the example terms "below" and "below" can include both above and below orientations. The device can be positioned otherwise (e.g., rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein should be interpreted accordingly.

[0040] It will be understood that when an element or layer is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it can be directly on, directly connected to, or directly coupled to the other element or layer, or one or more intervening elements or layers may be present. Additionally, it will be understood that when an element or layer is referred to as being “between” two elements or layers, it can be the only element or layer between the two elements or layers, or one or more intervening elements or layers may also be present.

[0041] The term used here is for the purpose of describing a specific embodiment, and is not intended to limit the present invention. As used here, unless the context clearly indicates otherwise, the singular form "one" and "one (kind / person)" are also intended to include plural forms. It will also be understood that when the terms "include" and "comprise" and their variations are used in this specification, the descriptions indicate the existence of stated features, integral bodies, steps, operations, elements and / or components, but do not exclude the existence or addition of one or more other features, integral bodies, steps, operations, elements, components and / or their groups. As used here, the term "and / or" includes any combination and all combinations of one or more of the related listed items. Such as "at least one (kind / person) in ... " The expression modifies the entire column of elements after a column of elements, without modifying the single element in the column.

[0042] As used herein, the terms "substantially", "approximately" and similar terms are used as approximate terms rather than as terms of degree, and are intended to explain the inherent variations of measured or calculated values ​​that will be recognized by those of ordinary skill in the art. In addition, the use of "may" when describing embodiments of the present invention refers to "one or more embodiments of the present invention". In addition, the use of alternative terms such as "or (or)" when describing embodiments of the present invention refers to "one or more embodiments of the present invention" for each corresponding item listed. As used herein, the term "using" and its variations can be considered to be synonymous with the term "utilizing" and its variations, respectively. In addition, the term "exemplary" is intended to indicate an example or illustration.

[0043] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. It will also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and / or this specification, and should not be interpreted in an idealized or overly formal sense unless explicitly defined as such herein.

[0044] Figure 1 is a block diagram illustrating a display device according to some example embodiments of the present disclosure.

[0045] Reference Figure 1 The display device may include a display panel 100 , a brightness control unit (or brightness controller, or brightness control circuit) 200 , a display panel driver 400 , and a power provider (or power supply or power supply unit) 500 .

[0046] The display panel 100 may include a plurality of pixels P and may display an image. The display panel 100 may be coupled to a scan driver 420 via a plurality of scan lines, may be coupled to an emission driver 440 via a plurality of emission control lines EL1 to ELn, and may be coupled to a data driver 460 via a plurality of data lines DL1 to DLm. The plurality of pixels P are located at intersections of the plurality of scan lines, the plurality of emission control lines EL1 to ELn, and the plurality of data lines DL1 to DLm, so the display panel 100 may include n×m pixels P, where "n" and "m" are natural numbers greater than zero.

[0047] According to some example embodiments, each pixel P may include an organic light emitting diode. The organic light emitting diode emits light having a brightness corresponding to a data voltage applied from a data driver 460 in response to an emission control signal transmitted through a corresponding emission control line among emission control lines EL1 to ELn. According to some example embodiments, each pixel P may be provided with a corresponding scan signal among scan signals GW1 to GWn from a scan driver 420, a corresponding initialization signal GI1 to GIn, and a corresponding bypass signal GB1 to GBn. The initialization signal may correspond to a previous scan signal among the scan signals, and the bypass signal may correspond to a next scan signal among the scan signals. The initialization signal may initialize a gate voltage of a driving transistor included in the pixel P. The bypass signal may initialize an anode voltage of an organic light emitting diode included in the pixel P to prevent excitation of black brightness.

[0048] Will refer to Figure 2 The configuration of the pixel P included in the display panel 100 is described in more detail.

[0049] The brightness control unit 200 may control the brightness of an image displayed by the display panel 100 by utilizing brightness control. For example, according to some example embodiments of the present disclosure, the brightness control unit 200 may perform different brightness controls according to the ambient illuminance LUX.

[0050] According to some example embodiments, the brightness control unit 200 may include: a driving power voltage determiner configured to determine a low potential driving power voltage ELVSS in response to an ambient illuminance LUX and a target brightness TB; a gamma voltage setting unit (or a gamma voltage setter, or a gamma voltage setting circuit) configured to determine a target brightness for a reference brightness in response to the ambient illuminance LUX and set a gamma voltage based on the target brightness; and a brightness modulator configured to correct the gamma voltage according to an average pixel level (APL) of input image data DATA.

[0051] According to some example embodiments, the brightness control unit 200 may be included in the controller 480 or included in the power provider 500. Figures 3 to 8 The brightness control method of the brightness control unit 200 is described in more detail.

[0052] The display panel driver 400 may drive the display panel 100 based on input image data DATA and gamma voltages GV0 to GV255. According to some example embodiments, the display panel driver 400 may include a scan driver 420, an emission driver 440, a data driver 460, and a controller 480.

[0053] The scan driver 420 may provide scan signals to the display panel 100 through a plurality of scan lines. According to some example embodiments, the scan driver 420 may provide scan signals GW1 to GWn, initialization signals GI1 to GIn, and bypass signals GB1 to GBn through the scan lines to the display panel 100. According to some example embodiments, each scan line may be coupled to a pixel P located on each pixel row of the display panel 100.

[0054] The emission driver 440 may provide an emission control signal to the display panel 100 through the plurality of emission control lines EL1 to ELn. According to some example embodiments, each of the emission control lines EL1 to ELn may be coupled to a pixel P located on each pixel row of the display panel 100.

[0055] The data driver 460 may provide data voltages based on the selected gamma voltages GV0 to GV255 to the display panel 100 through the plurality of data lines DL1 to DLm. Each of the data lines DL1 to DLm may be coupled to a pixel P located on each pixel row of the display panel 100.

[0056] The controller 480 may control the scan driver 420, the emission driver 440, the data driver 460, and the power provider 500 based on the first to fourth control signals CON1 to CON4. According to some example embodiments, the controller 480 may receive input image data DATA and input control signals from an image source such as an external graphic device.

[0057] The power provider 500 may provide the high potential driving power voltage ELVDD and the low potential driving power voltage ELVSS to the display panel 100 under the control of the brightness control unit 200. According to some example embodiments, the power provider 500 may be included in the brightness control unit 200. According to some example embodiments, the power provider 500 may also provide the initialization power voltage VINT to the display panel 100. According to some example embodiments, the initialization power voltage VINT may be set based on the low potential driving power voltage ELVSS, but the present disclosure is not limited thereto.

[0058] Figure 2 is a diagram showing some example embodiments Figure 1 FIG. 4 is a diagram showing further details of a pixel P shown in FIG.

[0059] Reference Figure 2 , the pixel P may include first to seventh transistors T1 to T7 , a storage capacitor Cst, and an organic light emitting diode EL.

[0060] The first transistor (driving transistor) T1 may include a gate electrode coupled to a first electrode of the storage capacitor Cst, a first electrode electrically coupled to the high potential driving power voltage ELVDD via a fifth transistor T5, and a second electrode electrically coupled to an anode of the organic light emitting diode EL via a sixth transistor T6. The first transistor T1 may receive a data signal VDATA according to a switching operation of the second transistor T2 to supply a driving current to the organic light emitting diode EL.

[0061] The second transistor (switching transistor) T2 may include a gate electrode coupled to the scan line SLn, a first electrode coupled to the data line DL, and a second electrode coupled to the first electrode of the first transistor T1. The second transistor T2 may be turned on according to the scan signal GW transferred through the scan line SLn to transfer the data signal VDATA to the first electrode of the first transistor T1.

[0062] The third transistor (compensation transistor) T3 may include a gate electrode coupled to the scan line SLn, a first electrode coupled to the second electrode of the first transistor T1, and a second electrode commonly coupled to the first electrode of the storage capacitor Cst, the second electrode of the fourth transistor T4, and the gate electrode of the first transistor T1. The third transistor T3 may be turned on according to the scan signal GW to allow the first transistor T1 to be coupled in the form of a diode and compensate for the threshold voltage of the first transistor T1.

[0063] The fourth transistor (initialization transistor) T4 may include a gate electrode connected to the initialization line SLn-1 (e.g., the previous scan line), a first electrode electrically coupled to the initialization power voltage VINT, and a second electrode commonly coupled to the second electrode of the third transistor T3 and the gate electrode of the first transistor T1. The fourth transistor T4 may be turned on according to the initialization signal GI, thereby performing an initialization operation of initializing the gate voltage of the first transistor T1 by transferring the initialization power voltage VINT to the gate electrode of the first transistor T1. The initialization power voltage VINT may be a global voltage provided to the entire display panel. In addition, the initialization signal GI may correspond to the previous scan signal.

[0064] The fifth transistor (operation control transistor) T5 may include a gate electrode coupled to the emission control line ELn, a first electrode electrically coupled to the high potential driving power voltage ELVDD, and a second electrode coupled to the first electrode of the first transistor T1. The fifth transistor T5 may control the connection between the first electrode of the first transistor T1 and the high potential driving power voltage ELVDD based on the emission control signal Em.

[0065] The sixth transistor (emission control transistor) T6 may include a gate electrode coupled to the emission control line ELn, a first electrode commonly coupled to the second electrode of the first transistor T1 and the first electrode of the third transistor T3, and a second electrode electrically coupled to the anode of the organic light emitting diode EL. The fifth transistor T5 and the sixth transistor T6 may be turned on according to the emission control signal Em to enable emission current to flow through the organic light emitting diode EL.

[0066] The seventh transistor (bypass transistor) T7 may include a gate electrode coupled to the bypass control line SLn+1 (ie, the next scan line), a first electrode coupled to the second electrode of the sixth transistor T6 and the anode of the organic light emitting diode EL, and a second electrode electrically coupled to the initialization power voltage VINT. The seventh transistor T7 may be turned on according to the bypass signal GB provided from the bypass control line SLn+1 to apply the initialization power voltage VINT to the anode of the organic light emitting diode EL. Thus, the organic light emitting diode EL may be initialized. The seventh transistor T7 is an element required to clearly display a black image or black brightness. The bypass signal GB may correspond to the next scan signal of the scan signal GW.

[0067] The storage capacitor Cst may be coupled between the gate electrode of the first transistor T1 and the high potential driving power voltage ELVDD.

[0068] The anode of the organic light emitting diode EL may be commonly coupled to the second electrode of the sixth transistor T6 and the first electrode of the seventh transistor T7, and the cathode of the organic light emitting diode EL may be electrically coupled to the low potential driving power voltage ELVSS. The low potential driving power voltage ELVSS may be a voltage determined by the brightness control unit 200 corresponding to the ambient illuminance LUX and the target brightness TB of the display device. The low potential driving power voltage ELVSS may be a global voltage provided to the entire display panel.

[0069] In addition, despite the Figure 2 , the case where the first transistor T1 to the seventh transistor T7 are implemented with p-type transistors is shown, but the present disclosure is not limited thereto. That is, according to some example embodiments of the present disclosure, at least some or all of the first transistor T1 to the seventh transistor T7 may be implemented with n-type transistors. Therefore, various modifications may be made to the structure and driving method of the pixel P corresponding to the change in transistor type.

[0070] Figure 3 It is shown Figure 1 A block diagram of an example of a brightness control unit is shown in FIG. Figure 4 : is a diagram showing an example of a low potential driving power voltage corresponding to a reference brightness. Figure 5 : is a diagram showing an example of target brightness corresponding to reference brightness. Figure 6 : is a diagram showing an example of target brightness corresponding to reference brightness when brightness modulation is performed.

[0071] Reference Figure 3 , the brightness control unit 200 may include a driving power voltage determiner 220 , a gamma voltage setting unit 240 , and a brightness modulator 260 .

[0072] The brightness control unit 200 may determine the low potential driving power voltage ELVSS and the gamma voltages GV0 to GV255 based on the ambient illuminance LUX and the target brightness TB. In addition, the brightness control unit 200 may perform correction on the determined gamma voltages GV0 to GV255 based on the APL of the input image data DATA.

[0073] The driving power voltage determiner 220 may include low potential driving power voltages ELVSS0 to ELVSS10 corresponding to reference brightnesses DBV0 to DBV10 respectively when the ambient illuminance LUX is greater than or equal to the illuminance threshold. In addition, the driving power voltage determiner 220 may include low potential driving power voltages ELVSSL to ELVSS10 corresponding to reference brightnesses DBVL to DBV10 respectively when the ambient illuminance LUX is less than the illuminance threshold. The illuminance threshold may be, for example, 50 lux.

[0074] The zeroth reference brightness DBV0 may correspond to the brightest brightness, and the tenth reference brightness DBV10 may correspond to the darkest brightness. For example, the zeroth reference brightness is the maximum brightness of the display device and may correspond to about 200 lux. The tenth reference brightness may correspond to about 100 lux.

[0075] The Lth reference brightness DBVL may have a value between the zeroth reference brightness DBV0 and the first reference brightness DBV1, but the present disclosure is not limited thereto. The Lth reference brightness DBVL may be a maximum value of reference brightness allowed in a threshold low potential driving power voltage ELVSSTH to be described later.

[0076] According to some example embodiments, when the maximum reference brightness is 2000 lux, the Lth reference brightness DBVL may be 1880 lux, and the first reference brightness DBV1 may be 1500 lux. When setting the Lth reference brightness DBVL, setting the target brightness TB to a value greater than the Lth reference brightness DBVL may be limited by a user, an application, or the like.

[0077] Reference Figure 4 As shown in the first line 401, when the ambient illuminance LUX is greater than or equal to the illuminance threshold value, the zeroth low potential driving power voltage ELVSS0 to the tenth low potential driving power voltage ELVSS10 may be set to a value that is smaller as the reference brightness is brighter. For example, the zeroth low potential driving power voltage ELVSS0 among the zeroth low potential driving power voltage ELVSS0 to the tenth low potential driving power voltage ELVSS10 may correspond to the lowest voltage, and the tenth low potential driving power voltage ELVSS10 among the zeroth low potential driving power voltage ELVSS0 to the tenth low potential driving power voltage ELVSS10 may correspond to the highest voltage.

[0078] Reference Figure 4 As shown in the second line 402, when the ambient illumination LUX is less than the illumination threshold, the Lth low-potential driving power voltage ELVSSL to the tenth low-potential driving power voltage ELVSS10 can be set to a value that becomes smaller as the brightness from the tenth reference brightness DBV10 to the first threshold brightness LTH1 becomes brighter, and can be set to the same value (i.e., the threshold low-potential driving power voltage ELVSSTH) from the first threshold brightness LTH1 to the Lth reference brightness DBVL.

[0079] According to some example embodiments, the first threshold brightness LTH1 may be a minimum value of a reference brightness at which an abnormal output such as spots is not viewed on the display panel 100 even when the display panel 100 is driven by the same low potential driving power voltage ELVSS. The same low potential driving power voltage ELVSS may be a threshold low potential driving power voltage ELVSSTH to be described later. According to some example embodiments, the first threshold brightness LTH1 may be a first reference brightness DBV1, but the present disclosure is not limited thereto.

[0080] For example, the first threshold brightness LTH1 may be the first reference brightness DBV1, and the threshold low potential driving power voltage ELVSSTH may be the first low potential driving power voltage ELVSS1. Therefore, the low potential driving power voltage ELVSS for the Lth reference brightness DBVL and the low potential driving power voltage ELVSS for the first reference brightness DBV1 may be set equivalently to the threshold low potential driving power voltage ELVSSTH.

[0081] According to some example embodiments, Figure 4 As shown in , for when the ambient illuminance LUX is greater than or equal to the illuminance threshold and when the ambient illuminance LUX is less than the illuminance threshold, the first to tenth low potential driving power voltages ELVSS1 to ELVSS10 may be equally set, but the present disclosure is not limited thereto.

[0082] The driving power voltage determiner 220 may receive the ambient illuminance LUX and the target brightness TB. The driving power voltage determiner 220 may select one of the zeroth to tenth low potential driving power voltages ELVSS0 to ELVSS10 or one of the Lth to tenth low potential driving power voltages ELVSSL to ELVSS10 as the low potential driving power voltage ELVSS based on the ambient illuminance LUX and the target brightness TB.

[0083] For example, when the target brightness TB corresponds to the kth reference brightness, the driving power voltage determiner 220 may determine the kth low potential driving power voltage as the low potential driving power voltage ELVSS. When the target brightness TB corresponds to a reference brightness between the kth reference brightness and the k-1th reference brightness, the driving power voltage determiner 220 may determine the low potential driving power voltage ELVSS by interpolating the kth low potential driving power voltage and the k-1th low potential driving power voltage.

[0084] The driving power voltage determiner 220 may provide the determined low potential driving power voltage ELVSS to the power provider 500. The low potential driving power voltage ELVSS provided to the power provider 500 may be supplied to the display panel 100.

[0085] The gamma voltage setting unit 240 may include zeroth target brightness TL0 to tenth target brightness TL10 corresponding to the zeroth reference brightness DBV0 to the tenth reference brightness DBV10 respectively when the ambient illumination LUX is greater than or equal to the illumination threshold. In addition, the gamma voltage setting unit 240 may include the Lth target brightness TLL to the tenth target brightness TL10 corresponding to the Lth reference brightness DBVL to the tenth reference brightness DBV10 respectively when the ambient illumination LUX is less than the illumination threshold.

[0086] The illumination threshold may be, for example, 50 lux. The target brightness TL is the maximum value of the brightness allowed in the corresponding reference brightness. For example, the target brightness TL may be the brightness at a white gray scale.

[0087] Reference Figure 5 As shown in the first line 501, when the ambient illuminance LUX is greater than or equal to the illuminance threshold, the zeroth target brightness TL0 to the tenth target brightness TL10 may be set to a value that is larger as the reference brightness is brighter. For example, the zeroth target brightness TL0 among the zeroth target brightness TL0 to the tenth target brightness TL10 may correspond to the highest brightness, and the tenth target brightness TL10 among the zeroth target brightness TL0 to the tenth target brightness TL10 may correspond to the lowest brightness. For example, the zeroth target brightness TL0 may be 1200nit (nit), and the tenth target brightness TL10 may be 2nit.

[0088] Reference Figure 5 As shown in the second line 502, when the ambient illuminance LUX is less than the illuminance threshold, the Lth target brightness TLL to the tenth target brightness TL10 may be set to a value that is larger as the reference brightness is brighter. For example, the Lth target brightness TLL among the Lth target brightness TLL to the tenth target brightness TL10 may correspond to the highest brightness, and the tenth target brightness TL10 among the Lth target brightness TLL to the tenth target brightness TL10 may correspond to the lowest brightness. For example, the Lth target brightness TLL may be 1000nit, and the tenth target brightness TL10 may be 2nit.

[0089] According to some example embodiments of the present disclosure, since the Lth reference brightness DBVL has a brightness darker than the zeroth reference brightness DBV0, the Lth target brightness TLL may be set to a value less than the zeroth target brightness TL0. According to some example embodiments, when the Lth reference brightness DBVL has a value between the zeroth reference brightness DBV0 and the first reference brightness DBV1, the Lth target brightness TLL may be set to a value between the zeroth target brightness TL0 and the first target brightness TL1. For example, when the zeroth target brightness TL0 is 1200nit and the first target brightness TL1 is 650nit, the Lth target brightness TLL may be set to 1000nit.

[0090] According to some example embodiments, Figure 5 As shown in , for when the ambient illuminance LUX is greater than or equal to the illuminance threshold and when the ambient illuminance LUX is less than the illuminance threshold, the first to tenth target brightnesses TL1 to TL10 may be equally set, but the embodiments of the present disclosure are not limited thereto.

[0091] The gamma voltage setting unit 240 may determine the target brightness TL based on the ambient illumination LUX and the target brightness TB. When the target brightness TL is determined, the gamma voltage setting unit 240 may set the gamma voltages GV0 to GV255 for realizing the corresponding target brightness TL.

[0092] For example, when the target brightness TB corresponds to the kth reference brightness, the gamma voltage setting unit 240 may set the gamma voltages GV0 to GV255 to achieve the kth target brightness. When the target brightness TB corresponds to a reference brightness between the kth reference brightness and the k-1th reference brightness, the gamma voltage setting unit 240 may determine the target brightness TL by interpolating the kth target brightness and the k-1th target brightness.

[0093] When the APL of the input image data DATA is greater than the APL threshold, the brightness modulator 260 may include correction brightnesses RL0 to RL10 and RLL to RL10 corresponding to the reference brightnesses DBV0 to DBV10 and DBVL to DBV10, respectively. The APL threshold may be set to a value of 65% of the maximum APL of the input image data DATA.

[0094] According to some example embodiments of the present disclosure, the correction brightness RL0 to RL10 and RLL to RL10 may be set differently according to the ambient illuminance LUX. For example, when the ambient illuminance LUX is greater than or equal to the illuminance threshold, the zeroth correction brightness RL0 to the tenth correction brightness RL10 may be set. In addition, when the ambient illuminance LUX is less than the illuminance threshold, the Lth correction brightness RLL to the tenth correction brightness RL10 may be set.

[0095] Reference Figure 6 , the correction brightness RL0 to RL10 and RLL to RL10 are values ​​determined by applying the correction offset offset to the above-mentioned target brightness TL0 to TL10 and TLL to TL10, and can be set to be smaller than the target brightness TL0 to TL10 and TLL to TL10 in a reference brightness brighter than the second threshold brightness LTH2. The second threshold brightness LTH2 can be, for example, the second reference brightness DBV2, but the present disclosure is not limited thereto. In addition, the second threshold brightness LTH2 can be set to a value smaller than the above-mentioned first threshold brightness LTH1, but the present disclosure is not limited thereto.

[0096] Reference Figure 6 As shown in the first line 601, when the ambient illuminance LUX is greater than or equal to the illuminance threshold, the correction offset offset may increase from the second threshold luminance LTH2 to the zeroth reference luminance DBV0. The correction offset offset may be determined differently for reference luminances DBV0 and DBV1 brighter than the second threshold luminance LTH2.

[0097] Reference Figure 6 As shown in the second line 602, when the ambient illuminance LUX is less than the illuminance threshold, the correction offset offset may be increased from the second threshold luminance LTH2 to the first threshold luminance LTH1. In addition, the correction offset offset may be set to the same value from the first threshold luminance LTH1 to the Lth reference luminance DBVL, that is, the threshold correction offset offsetTH. The threshold correction offset offsetTH may be set to the maximum target brightness, for example, a value of 35% of the Lth target brightness TLL, but the present disclosure is not limited thereto.

[0098] When the APL of the input image data DATA is greater than the APL threshold, the brightness modulator 260 may correct the gamma voltages GV0 to GV255 set by the gamma voltage setting unit 240 based on the correction brightnesses RL0 to RL10 and RLL to RL10. That is, the brightness modulator 260 may determine the correction brightness RL based on the ambient illuminance LUX and the target brightness TB, and may correct the gamma voltages GV0 to GV255 so that the determined correction brightness RL may be achieved.

[0099] When the target brightness TL is corrected to the correction brightness RL, the gamma voltage (eg, GV255) with respect to the high gray scale may be reduced, and all the gamma voltages may be reduced corresponding to the reduced high gray scale gamma voltage. When all the gamma voltages GV0 to GV255 are reduced, the power consumption of the display panel 100 driven by the corrected gamma voltages GV0' to GV255' may be reduced.

[0100] Furthermore, according to some example embodiments as described above, Figure 2As shown in , a case where the transistors T1 to T7 in the pixel P are implemented with p-type transistors is described. According to some example embodiments, when the transistors T1 to T7 in the pixel P are implemented with n-type transistors, the gamma voltage (e.g., GV0) relative to the low gray scale may be reduced. Therefore, all gamma voltages may be reduced corresponding to the reduced low gray scale gamma voltage. Such modifications may also be applied to the following embodiments.

[0101] The brightness modulator 260 may output the corrected gamma voltages GV0 ′ to GV255 ′ to the data driver 460 .

[0102] Meanwhile, when the APL of the input image data DATA is less than or equal to the APL threshold, the target brightness TL may not be corrected by the brightness modulator 260. Therefore, the brightness modulator 260 does not correct the gamma voltages GV0 to GV255 set by the gamma voltage setting unit 240 but may output the gamma voltages GV0 to GV255 as they are.

[0103] As described above, the brightness controller 200 can control the low potential driving power voltage ELVSS and the gamma voltage according to the ambient illuminance LUX and the target brightness TB commonly applied to the display panel 100. For example, the brightness control unit 200 limits the low potential driving power voltage ELVSS to the threshold low potential driving power voltage ELVSSTH in a low brightness environment, and limits the reference brightness DBV to a value smaller than the maximum reference brightness DBV0 (e.g., the Lth reference brightness DBVL), thereby preventing a weak bright spot from being viewed or perceived in the display panel 100. In addition, the brightness control unit 200 performs brightness correction according to the APL of the input image data DATA, thereby reducing the power consumption of the display panel 100.

[0104] Figure 7 is a diagram showing an example in which a reference brightness, a target brightness, and a low-potential driving power voltage are set in a high-illuminance environment. Figure 8 is a diagram showing an example in which a reference brightness, a target brightness, and a low-potential driving power voltage are set in a low-illuminance environment.

[0105] Reference Figure 7 and Figure 8 , the brightness controller 200 may include a plurality of low potential driving power voltages ELVSS corresponding to a plurality of reference brightnesses DBV0 to DBV10 and DBVL to DVB10 and a plurality of target brightnesses TL.

[0106] The low potential driving power voltage ELVSS and the target brightness TL of the display device can be divided according to a plurality of reference brightnesses DBV0 to DBV10 and DBVL to DVB10. The reference brightness DBV in a high illumination environment can be divided into a zeroth reference brightness DBV0 to a tenth reference brightness DBV10. The zeroth reference brightness DBV0 can be the highest brightness, and the tenth reference brightness DBV10 can be the lowest brightness. The reference brightness DBV in a low illumination environment can be divided into an Lth reference brightness DBVL to a tenth reference brightness DBV10. The Lth reference brightness DBVL can be a brightness darker than the zeroth reference brightness DBV0.

[0107] In a high illumination environment, the low potential driving power voltage ELVSS can be set to a smaller value as the reference brightness becomes brighter. For example, the low potential driving power voltage ELVSS corresponding to the zeroth reference brightness DBV0 can be set to -5V, and the low potential driving power voltage ELVSS corresponding to the tenth reference brightness DBV10 can be set to -1.5V.

[0108] In a low illumination environment, the low potential driving power voltage ELVSS corresponding to the Lth reference brightness DBVL can be set to be greater than the low potential driving power voltage ELVSS corresponding to the zeroth reference brightness DBV0. For example, the low potential driving power voltage ELVSS corresponding to the Lth reference brightness DBVL can be set to the same value as the low potential driving power voltage ELVSS corresponding to the first reference brightness DBV1, that is, -3.1V.

[0109] In a high illumination environment, the target brightness TL may be set to a larger value as the reference brightness becomes brighter. For example, the target brightness TL corresponding to the zeroth reference brightness DBV0 may be set to 1200 nit, and the target brightness TL corresponding to the tenth reference brightness DBV10 may be set to 2 nit. However, this is merely illustrative, and the scope of the present disclosure is not limited to the above reference values.

[0110] In a low illumination environment, the target brightness TL corresponding to the Lth reference brightness DBVL can be set to be smaller than the target brightness TL corresponding to the zeroth reference brightness DBV0. For example, when the target brightness TL corresponding to the zeroth reference brightness DBV0 is set to 1200nit, the target brightness TL corresponding to the Lth reference brightness DBVL can be set to 1000nit.

[0111] According to some example embodiments, the brightness control unit 200 may further include a threshold correction offset offsetTH for brightness modulation of the input image data DATA. The threshold correction offset offsetTH may be set for low illumination, and may be set for an Lth reference brightness DBVL.

[0112] Fig. 9 is a diagram showing some example embodiments Figure 1 A block diagram of an example of a brightness control unit (or brightness controller or brightness control circuit) shown in FIG.

[0113] Reference Fig. 9 According to some example embodiments, the brightness control unit 200 ′ may include a driving power voltage determiner 220 , a gamma voltage setting unit (or a gamma voltage setter, or a gamma voltage setting circuit) 240 ′, and a brightness modulator 260 ′.

[0114] The driving power voltage determiner 220 may include low potential driving power voltages ELVSS0 to ELVSS10 corresponding to reference brightnesses DBV0 to DBV10 respectively when the ambient illuminance LUX is greater than or equal to the illuminance threshold. In addition, the driving power voltage determiner 220 may include low potential driving power voltages ELVSSL to ELVSS10 corresponding to reference brightnesses DBVL to DBV10 respectively when the ambient illuminance LUX is less than the illuminance threshold. The illuminance threshold may be, for example, 50 lux.

[0115] The zeroth reference brightness DBV0 may correspond to the brightest brightness, and the tenth reference brightness DBV10 may correspond to the darkest brightness. For example, the zeroth reference brightness DBV0 is the maximum brightness of the display device and may correspond to about 200 lux. The tenth reference brightness DBV10 may correspond to about 100 lux.

[0116] The Lth reference brightness DBVL may have a value between the zeroth reference brightness DBV0 and the first reference brightness DBV1, but the present disclosure is not limited thereto. The Lth reference brightness DBVL may be a maximum value of the reference brightness allowed in the threshold low potential driving power voltage ELVSSTH which has been described in detail above.

[0117] According to some example embodiments, when the maximum reference brightness is 2000 lux, the Lth reference brightness DBVL may be 1880 lux, and the first reference brightness DBV1 may be 1500 lux. When setting the Lth reference brightness DBVL, setting the target brightness TB to a value greater than the Lth reference brightness DBVL may be limited by a user, an application, or the like.

[0118] According to some example embodiments, the first threshold brightness LTH1 may be a minimum value of a reference brightness at which an abnormal output such as spots is not viewed or perceived on the display panel 100 even when the display panel 100 is driven by the same low potential driving power voltage ELVSS. The same low potential driving power voltage ELVSS may be the threshold low potential driving power voltage ELVSSTH already described above. According to some example embodiments, the first threshold brightness LTH1 may be a first reference brightness DBV1, but example embodiments according to the present disclosure are not limited thereto.

[0119] For example, the first threshold brightness LTH1 may be the first reference brightness DBV1, and the threshold low potential driving power voltage ELVSSTH may be the first low potential driving power voltage ELVSS1. Therefore, the low potential driving power voltage ELVSS for the Lth reference brightness DBVL and the low potential driving power voltage ELVSS for the first reference brightness DBV1 may be set equivalently to the threshold low potential driving power voltage ELVSSTH.

[0120] The driving power voltage determiner 220 may receive the ambient illuminance LUX and the target brightness TB. The driving power voltage determiner 220 may select one of the zeroth to tenth low potential driving power voltages ELVSS0 to ELVSS10 or one of the Lth to tenth low potential driving power voltages ELVSSL to ELVSS10 as the low potential driving power voltage ELVSS based on the ambient illuminance LUX and the target brightness TB.

[0121] For example, when the target brightness TB corresponds to the kth reference brightness, the driving power voltage determiner 220 may determine the kth low potential driving power voltage as the low potential driving power voltage ELVSS. When the target brightness TB corresponds to a reference brightness between the kth reference brightness and the k-1th reference brightness, the driving power voltage determiner 220 may determine the low potential driving power voltage ELVSS by interpolating the kth low potential driving power voltage and the k-1th low potential driving power voltage.

[0122] The driving power voltage determiner 220 may provide the determined low potential driving power voltage ELVSS to the power provider 500. The low potential driving power voltage ELVSS provided to the power provider 500 may be supplied to the display panel 100.

[0123] The gamma voltage setting unit 240' may include gamma voltage groups GVSET0 to GVSET10 corresponding to the zeroth reference brightness DBV0 to the tenth reference brightness DBV10 respectively when the ambient illumination LUX is greater than or equal to the illumination threshold. In addition, the gamma voltage setting unit 240' may include gamma voltage groups GVSETL to GVSET10 corresponding to the Lth reference brightness DBVL to the tenth reference brightness DBV10 respectively when the ambient illumination LUX is less than the illumination threshold.

[0124] Each of the gamma voltage groups GVSET0 to GVSET10 and GVSETL to GVSET10 may include gamma voltages GV0 to GV255. The gamma voltages GV0 to GV255 included in any gamma voltage group may be set to achieve a target brightness of a reference brightness mapped to the corresponding gamma voltage group. The target brightness TL may be set to a larger value as the reference brightness is brighter, but the exemplary embodiments according to the present disclosure are not limited thereto.

[0125] The gamma voltage setting unit 240' may select any one of the gamma voltage sets GVSET0 to GVSET10 and GVSETL to GVSET11 based on the ambient illuminance LUX and the target brightness TB. For example, when the target brightness TB corresponds to the kth reference brightness, the gamma voltage setting unit 240' may select the gamma voltage set corresponding to the kth target brightness.

[0126] According to some example embodiments, when the target brightness TB corresponds to a reference brightness between a kth reference brightness and a k-1th reference brightness, the gamma voltage setting unit 240' may generate a gamma voltage group by interpolating gamma voltages GV0 to GV255 of the gamma voltage group corresponding to the kth reference brightness and gamma voltages GV0 to GV255 of the gamma voltage group corresponding to the k-1th reference brightness.

[0127] The gamma voltage setting unit 240 ′ may transfer the selected gamma voltage set to the brightness modulator 260 ′.

[0128] When the APL of the input image data DATA is greater than the APL threshold, the brightness modulator 260' may correct the gamma voltages GV0 to GV255 of the gamma voltage group delivered from the gamma voltage setting unit 240'. For example, the APL threshold may be set to a value that is 65% of the maximum APL of the input image data DATA.

[0129] When the APL of the input image data DATA is greater than the APL threshold, the brightness modulator 260' may include correction gamma voltage groups GVSET0' to GVSET10' and GVSETL' to GVSET10' for the gamma voltage groups GVSET0 to GVSET10 and GVSETL to GVSET10. Therefore, the brightness modulator 260' may select the correction gamma voltage group corresponding to the gamma voltage group transferred from the gamma voltage setting unit 240'.

[0130] The brightness modulator 260' may include correction values ​​for the gamma voltages GV0 to GV255 included in the gamma voltage groups GVSET0 to GVSET10 and GVSETL to GVSET10. Therefore, the brightness modulator 260' may correct the gamma voltage group transferred from the gamma voltage setting unit 240' using the corresponding correction values.

[0131] According to some example embodiments, when the gamma voltage setting unit 240 ′ delivers a gamma voltage group generated by interpolation, the brightness modulator 260 ′ may generate a correction gamma voltage group by interpolating prestored correction gamma voltage groups GVSET0 ′ to GVSET10 ′ and GVSETL ′ to GVSET10 ′ or prestored correction values.

[0132] The correction gamma voltage groups GVSET0' to GVSET10' and GVSETL' to GVSET10' may include correction gamma voltages GV0' to GV255', which correspond to the ambient illuminance LUX and the reference brightness DBV0 to DBV10 and DBVL to DBV10 to achieve a predetermined correction brightness RL. The correction brightness RL may be a brightness obtained by correcting the target brightness TL corresponding to the reference brightness DBV0 to DBV10 and DBVL to DBV10 based on the correction offset offset.

[0133] The brightness modulator 260 ′ may output the selected corrected gamma voltage group to the data driver 460 .

[0134] Meanwhile, when the APL of the input image data DATA is less than or equal to the APL threshold, the gamma voltages GV0 to GV255 may not be corrected by the brightness modulator 260'. Therefore, the brightness modulator 260' does not correct the gamma voltage group transferred from the gamma voltage setting unit 240' but may output the gamma voltage group as it is.

[0135] Reference Figures 3 to 8 The described embodiments may be applied identically or similarly to Fig. 9 That is, in reference to Fig. 9In the described embodiment, the gamma voltages GV0 to GV255 of the gamma voltage group selected based on the ambient illuminance LUX, the target brightness TB, and the APL of the input image data DATA may be preset and stored in accordance with the reference Figures 3 to 8 In each component of the brightness controller 200' of the described embodiment.

[0136] Fig.10 It is shown Figure 1 A block diagram of an example of a brightness control unit (or brightness controller) is shown in FIG.

[0137] Reference Fig.10 , the brightness control unit 200 ″ may include a driving power voltage determiner 220 and a gamma voltage setting unit 240 ″.

[0138] and Figure 3 and Fig. 9 Compared with the embodiment shown in FIG. 1 , when the APL of the input image data DATA is less than or equal to the APL threshold, according to Fig.10 The brightness controller 200'' of the embodiment shown in FIG. 1 may store the gamma voltage groups GVSET0 to GVSET10 and GVSETL to GVSET10 corresponding to the ambient illuminance LUX, and when the APL of the input image data DATA is greater than the APL threshold, Fig.10 The brightness controller 200'' of the embodiment shown in FIG. 1 may store the correction gamma voltage groups GVSET0' to GVSET10' and GVSETL' to GVSET10' corresponding to the ambient illuminance LUX. The gamma voltage groups GVSET0 to GVSET10 and GVSETL to GVSET10 and the correction gamma voltage groups GVSET0' to GVSET10' and GVSETL' to GVSET10' may include the same as those according to the reference Figures 3 to 8 The described embodiment sets the gamma voltages GV0 to GV255 to be equal to the gamma voltages GV0 to GV255.

[0139] Therefore, the gamma voltage setting unit 240 ″ may select any one gamma voltage set among the gamma voltage sets GVSET0 to GVSET10 and GVSETL to GVSET10 and the correction gamma voltage sets GVSET0 ′ to GVSET10 ′ and GVSETL ′ to GVSET10 ′ based on the ambient illuminance LUX, the APL of the input image data DATA, and the target brightness TB.

[0140] According to some example embodiments, the gamma voltage setting unit 240 ″ may require additional storage space, but does not require real-time calculation for determining the gamma voltage, thereby enabling faster data processing.

[0141] In a brightness control unit and a display device including the same according to some example embodiments of the present disclosure, the low potential driving power voltage and the target brightness can be limited in a low illumination environment. Therefore, weak bright spots can be prevented from being viewed or perceived in the display panel, and the image quality of the display device can be improved.

[0142] Furthermore, in the brightness control unit and the display device including the same according to some example embodiments of the present disclosure, brightness correction using the ACL function may be adaptively performed according to ambient illumination, so that power consumption of the display panel 100 may be reduced.

[0143] Various aspects of some exemplary embodiments have been disclosed herein, and although specific terms are employed, they are used and interpreted in a general and descriptive sense only, and not for purposes of limitation. In some cases, as will be apparent to one of ordinary skill in the art upon filing this application, unless otherwise specifically shown, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments. Therefore, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the present disclosure as set forth in the appended claims and their equivalents.

Claims

1. A brightness control unit, the brightness control unit comprising: a driving power voltage determiner configured to determine a driving power voltage to be supplied to the display panel based on a plurality of driving power voltages respectively corresponding to a plurality of reference brightnesses of the display panel, the driving power voltage supplied to the display panel corresponding to a target brightness; as well as a gamma voltage setting unit configured to determine a target brightness for achieving the target brightness based on a plurality of target brightnesses respectively corresponding to the maximum brightness values ​​allowed among the plurality of reference brightnesses, and set a gamma voltage for achieving the target brightness, Wherein, the reference brightness is set according to the ambient illumination of the display panel.

2. The brightness control unit according to claim 1, wherein: When the ambient illuminance is less than an illuminance threshold, the maximum value of the reference luminance is set to be smaller than the maximum reference luminance of the display panel.

3. The brightness control unit according to claim 1, wherein: A driving power voltage supplied to the display panel is set differently for the same reference brightness according to the ambient illuminance.

4. The brightness control unit according to claim 3, wherein: The driving power voltage determiner is configured to set the driving power voltage supplied to the display panel to be equivalent to a threshold driving power voltage corresponding to a reference luminance greater than a threshold luminance in response to the ambient luminance being less than a luminance threshold.

5. The brightness control unit according to claim 4, wherein: The threshold brightness is a minimum value of reference brightness for which an abnormal output is not viewed on the display panel when the display panel is driven by the threshold driving power voltage.

6. The brightness control unit according to claim 1, wherein: The gamma voltage is set differently for the same reference brightness according to the ambient illuminance. 7 . The brightness control unit according to claim 6 , further comprising a brightness modulator configured to correct the gamma voltage in response to an average pixel level of input image data being greater than or equal to an average pixel level threshold.

8. The brightness control unit according to claim 7, wherein: The brightness modulator is configured to determine a correction brightness for the target brightness based on the target brightness, and correct the gamma voltage to achieve the correction brightness.

9. The brightness control unit according to claim 8, wherein: The brightness modulator is configured to, in response to the ambient illuminance being smaller than an illuminance threshold, equally set the correction brightness corresponding to a reference luminance greater than a threshold luminance.

10. The brightness control unit according to claim 8, wherein: The brightness modulator is configured to set the correction brightness so that a difference between the correction brightness for a maximum value of the reference brightness and the target brightness corresponds to a threshold correction offset in response to the ambient illuminance being smaller than an illuminance threshold.

11. A brightness control unit, comprising: a driving power voltage determiner configured to determine a driving power voltage to be supplied to the display panel based on a plurality of driving power voltages respectively corresponding to a plurality of reference brightnesses of the display panel, the driving power voltage supplied to the display panel corresponding to a target brightness; as well as a gamma voltage setting unit configured to determine a target brightness for achieving the target brightness based on a plurality of target brightnesses respectively corresponding to the maximum brightness values ​​allowed among the plurality of reference brightnesses, and set a gamma voltage for achieving the target brightness, The driving power voltage provided to the display panel is set differently for the same reference brightness according to the ambient illumination of the display panel.

12. The brightness control unit according to claim 11, wherein: The driving power voltage determiner is configured to set the driving power voltage supplied to the display panel to be equivalent to a threshold driving power voltage corresponding to a reference luminance greater than a threshold luminance in response to the ambient luminance being less than a luminance threshold.

13. A brightness control unit, comprising: a driving power voltage determiner configured to determine a driving power voltage to be supplied to the display panel based on a plurality of driving power voltages respectively corresponding to a plurality of reference brightnesses of the display panel, the driving power voltage supplied to the display panel corresponding to a target brightness; as well as a gamma voltage setting unit configured to determine a target brightness for achieving the target brightness based on a plurality of target brightnesses respectively corresponding to the maximum brightness values ​​allowed among the plurality of reference brightnesses, and set a gamma voltage for achieving the target brightness, The gamma voltage is set differently for the same reference brightness according to the ambient illumination of the display panel.

14. A display device, comprising: A display panel including a plurality of pixels; a brightness control unit configured to: determine a driving power voltage based on a target brightness of the display panel, and set a gamma voltage for achieving a target brightness, the target brightness being used to achieve the target brightness; a display panel driver configured to drive the display panel based on the gamma voltage; as well as a power provider configured to provide the determined driving power voltage to the display panel, The brightness control unit includes: a driving power voltage determiner configured to determine the driving power voltage to be provided to the display panel based on a plurality of driving power voltages respectively corresponding to a plurality of reference brightnesses of the display panel, the driving power voltage provided to the display panel corresponding to the target brightness; and a gamma voltage setting unit configured to determine the target brightness based on a plurality of target brightnesses respectively corresponding to the maximum brightness values ​​allowed in the plurality of reference brightnesses, and set the gamma voltage, Wherein, the reference brightness is set according to the ambient illumination of the display panel.

15. The display device according to claim 14, wherein: When the ambient illuminance is less than an illuminance threshold, the maximum value of the reference luminance is set to be smaller than the maximum reference luminance of the display panel.

16. The display device according to claim 14, wherein: A driving power voltage supplied to the display panel is set differently for the same reference brightness according to the ambient illuminance.

17. The display device according to claim 16, wherein: The driving power voltage determiner is configured to, in response to the ambient illuminance being smaller than an illuminance threshold, set the driving power voltage supplied to the display panel to be equivalent to a threshold driving power voltage corresponding to a reference luminance greater than a threshold luminance, and The threshold brightness is a minimum value of reference brightness for which no abnormal output is observed on the display panel when the display panel is driven by the threshold driving power voltage.

18. The display device according to claim 14, wherein: The gamma voltage is set differently for the same reference brightness according to the ambient illuminance.

19. The display device according to claim 18, wherein: The brightness control unit further includes a brightness modulator configured to correct the gamma voltage in response to an average pixel level of input image data being greater than or equal to an average pixel level threshold.

20. An electronic device, comprising: a processor configured to provide input image data; A display panel including a plurality of pixels; a brightness control unit configured to: determine a driving power voltage based on a target brightness of the display panel, and set a gamma voltage for achieving a target brightness, the target brightness being used to achieve the target brightness; a display panel driver configured to drive the display panel based on the gamma voltage and the input image data; as well as a power provider configured to provide the determined driving power voltage to the display panel, The brightness control unit includes: a driving power voltage determiner configured to determine the driving power voltage to be provided to the display panel based on a plurality of driving power voltages respectively corresponding to a plurality of reference brightnesses of the display panel, the driving power voltage provided to the display panel corresponding to the target brightness; and a gamma voltage setting unit configured to determine the target brightness based on a plurality of target brightnesses respectively corresponding to the maximum brightness values ​​allowed in the plurality of reference brightnesses, and set the gamma voltage, Wherein, the reference brightness is set according to the ambient illumination of the display panel.

Images