Backlight panel including light emitting diodes configured to emit light of different colors and display device including same

Abstract

A display device according to an embodiment may comprise: a display panel; a backlight panel including light emitting diodes (LEDs) configured to emit light of different colors, wherein the LEDs include a first LED and a second LED; a pixel control circuit connected to cathodes of the LEDs; and a power circuit connected to power lines respectively connected to anodes of the LEDs. The power circuit may be configured to apply a first voltage for driving the first LED among the LEDs to a first power line connected to the first LED among the power lines. The power circuit may be configured to apply a second voltage for driving the second LED among the LEDs to a second power line connected to the second LED among the power lines. The second voltage may be different from the first voltage.

Description

A backlight panel comprising light-emitting diodes configured to emit lights of different colors and a display device comprising the same

[0001] The present disclosure relates to a backlight panel including light emitting diodes (LEDs) configured to emit light of different colors and a display device including the same.

[0002] Recent advancements in electronic technology have led to the development and proliferation of various types of display devices, and the demand for large-scale displays is increasing. Display devices can display colors using liquid crystals that control light transmittance. A backlight panel can generate light that is directed toward a display panel (e.g., a display panel containing liquid crystals) that displays colors.

[0003] The above information may be provided as background art to aid in understanding the present disclosure. No claim or determination is made as to whether any of the above is applicable as prior art related to the present disclosure.

[0004] According to one embodiment, a display device may include a display panel, a backlight panel including light emitting diodes (LEDs) arranged toward the display panel and configured to emit light having different colors, a pixel control circuit connected to cathodes of the LEDs, and a power circuit connected to power lines respectively connected to anodes of the LEDs. The power circuit may be configured to apply a first voltage for driving a first LED among the LEDs to a first power line connected to the first LED among the power lines. The power circuit may be configured to apply a second voltage for driving a second LED among the LEDs to a second power line connected to the second LED among the power lines. The second voltage may be different from the first voltage.

[0005] In one embodiment, a display device may include a display panel, a backlight panel including a plurality of backlight pixels, each of the backlight pixels including light emitting diodes (LEDs) arranged toward the display panel and configured to emit light having different colors, a set of pixel control circuits connected to each of the plurality of backlight pixels, and a power circuit connected to a plurality of power lines. The plurality of power lines may include a first power line connected to a first group of LEDs having a first color among the LEDs included in the plurality of backlight pixels, and a second power line connected to a second group of LEDs having a second color among the LEDs included in the plurality of backlight pixels. The power circuit may be configured to apply a first voltage to each of the LEDs in the first group via the first power line. The power circuit may be configured to apply a second voltage, different from the first voltage, to each of the LEDs in the second group via the second power line.

[0006] In one embodiment, a method of a display device may be provided. The display device may include a backlight panel including light emitting diodes (LEDs) configured to emit light having different colors, a pixel control circuit connected to cathodes of the LEDs, and a power circuit connected to power lines respectively connected to anodes of the LEDs. The method may include an operation of controlling the power circuit to apply a first voltage for driving a first LED among the LEDs to a first power line connected to the first LED among the power lines. The method may include an operation of controlling the power circuit to apply a second voltage for driving a second LED among the LEDs to a second power line connected to the second LED among the power lines. The second voltage may be different from the first voltage.

[0007] The above and other aspects, features, and advantages of some embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0008] FIG. 1 illustrates a display device according to one embodiment;

[0009] FIGS. 2A and 2B are diagrams of a backlight panel included in a display device, according to one embodiment;

[0010] Figure 3 is an exemplary timing diagram for explaining the driving time of LEDs of a backlight panel;

[0011] FIG. 4 is a graph illustrating a color range that can be expressed by a display device according to one embodiment; and

[0012] FIG. 5 is an exemplary flowchart for the operation of a display device according to one embodiment.

[0013] Hereinafter, various embodiments of the present disclosure are described with reference to the attached drawings.

[0014] The various embodiments of the present disclosure and the terminology used therein are not intended to limit the technology described in the present disclosure to a specific embodiment, but should be understood to include various modifications, equivalents, and / or substitutes of the embodiments. In connection with the description of the drawings, similar reference numerals may be used for similar components. The singular expressions may include plural expressions unless the context clearly indicates otherwise. In the present disclosure, expressions such as “A or B,” “at least one of A and / or B,” “A, B, or C,” or “at least one of A, B, and / or C” can include all possible combinations of the items listed together. Expressions such as “first,” “second,” “first,” or “second” can modify the corresponding components regardless of order or importance, and are only used to distinguish one component from another, but do not limit the corresponding components. When it is said that a component (e.g., a first component) is “(functionally or communicatively) connected” or “connected” to another component (e.g., a second component), said component may be directly connected to said other component, or may be connected via another component (e.g., a third component).

[0015] The term "module" as used herein includes a unit composed of hardware, and may be used interchangeably with terms such as component, circuit, etc. A module may be an integrally composed component, or a minimum unit or part thereof that performs one or more functions. For example, a module may be composed of an application-specific integrated circuit (ASIC).

[0016] FIG. 1 illustrates a display device (101) according to one embodiment. The display device (101) may be described as an electronic device capable of displaying images. In the present disclosure, the terms "display device" and "electronic device" may be used interchangeably. For example, the display device (101) may include a television (TV), a monitor, a computer, a smartphone, a tablet, a portable media player, a wearable device, a video wall, an electronic picture frame, and the like. Hereinafter, the display device (101) is described as being implemented as a TV, but the embodiments of the present disclosure are not limited thereto.

[0017] The display device (101) may be configured to operate by power (e.g., an alternating current (AC) power signal and / or an AC signal) provided from a power system (110). The display device (101) may include a plug (120) (or an electrical cord) configured to be connected to an outlet (or socket, receptacle) located at an end of the power system (110). The plug (120) may be connected to a component of the display device (101) for power conversion (e.g., from an AC signal to a direct current (DC) signal (or a DC power signal)) (e.g., an AC-DC adapter (or an electrical adapter), or a circuit included within the display device (101).

[0018] When the plug (120) is electrically connected to the power system (110) (or in a state), the display device (101) can execute a function for outputting an image, a sound, or a combination of the image and the sound (e.g., multimedia content) based on the power of the power system (110). When the display device (101) receives information representing an image and / or a sound, the display device (101) can execute the function using the information. The information representing an image and / or a sound can be stored in the display device (101) or received from an external electronic device (e.g., a set-top box (STB)) (130) connected to the display device (101). The display device (101) can include an antenna configured to wirelessly receive the information, or can be electrically connected to the antenna.

[0019] The display device (101) may include hardware for receiving user input for controlling the display device (101), such as user input for switching between a standby mode and a normal mode. For example, the display device (101) may include a switch (or button) that is at least partially visible through the housing of the display device (101). For example, the display device (101) may include a touch sensor (e.g., a resistive touch sensor and / or a capacitive touch sensor) for detecting a touch input on at least a portion of the housing. The user input may include a direct action of the user on the display device (101), such as pressing a switch and / or button, or touching a surface of the housing. However, embodiments of the present disclosure are not limited to the above examples. In one embodiment, the user input may be identified by an audio signal representing the user's speech received through a microphone. In one embodiment, the user input may include an indirect user action related to the display device (101), based on a remote controller (109).

[0020] Referring to FIG. 1, the display device (101) may be configured to receive a wireless signal (or an optical signal) of a remote controller (109) based on infrared (IR). However, one embodiment of the present disclosure is not limited to the above examples, and the remote controller (109) may be configured to transmit a wireless signal based on Bluetooth, Bluetooth low energy (BLE), near-field communication (NFC), ultra-wideband (UWB), wireless fidelity (WiFi), WiFi-direct, and / or other wireless short-range communication protocols, and the display device (101) may be configured to receive a wireless signal based on the exemplified wireless short-range communication protocols. In both the standby mode and the normal mode, the display device (101) may be configured to receive a wireless signal of the remote controller (109).

[0021] Referring to FIG. 1, a display device (101) may include a display panel (150) and a backlight panel (160). One side of the display device (101) from which at least a portion of the display panel (150) can be viewed may be referred to as a front side (e.g., a front side) of the display device (101). The display panel (150) may include a liquid crystal display (LCD), a plasma display panel (PDP), and / or a plurality of LEDs. The LEDs of the display panel (150) may include organic LEDs (OLEDs). In one embodiment, the display panel (150) may include electronic paper. When the display panel (150) has a flat shape, the display panel (150) may be referred to as a flat panel display (FPD). When the display panel (150) has a curved shape, the display panel (150) may be referred to as a curved display. When the display panel (150) has a deformable shape, the display panel (150) may be referred to as a bendable display, a flexible display, or a rollable display.

[0022] The backlight panel (160) of the display device (101) may be positioned below the display panel (150) when viewing the display device (101) from the front side. For example, the display panel (150) may be positioned on, or may be stacked with, the backlight panel (160). The backlight panel (160) may be configured to emit light toward the display panel (150). The display panel (150) may include a color filter, such as a liquid crystal. In the color filter, light emitted from the backlight panel (160) may be distorted or filtered. For example, in the color filter, a specific wavelength component of light may be (selectively or exclusively) output to the outside. The display device (101) can visualize images and / or videos by (locally) controlling color filters arranged in two dimensions on a flat (or curved) surface of the display panel (150).

[0023] In one embodiment, the backlight panel (160) may be referred to as a light source that generates light emitted from the display device (101) (or the display panel (150)). The backlight panel (160) may include light emitting diodes (LEDs) that are arranged toward the display panel (150) and configured to emit light having different colors (e.g., three primary colors of light, such as red, green, and / or blue). In the present disclosure, the backlight panel (160) may be referred to as a back light unit (BLU). The positional relationship of the LEDs arranged on one surface of the backlight panel (160) and the circuit for controlling the LEDs are described with reference to FIGS. 2A and 2B.

[0024] In one embodiment, the backlight panel (160) of the display device (101) may include LEDs of different colors to widen the range of colors (e.g., color gamut, gradation levels, and / or color reproduction characteristics) that can be expressed by the display device (101). The LED may be configured to emit light when it receives a voltage exceeding a threshold voltage (e.g., a forward voltage and / or a bias voltage). For example, the LED may be configured to emit light when a potential difference between its anode and cathode exceeds the threshold voltage. When the potential difference between the anode and cathode of the LED exceeds the threshold voltage, current may flow through the LED. The voltage applied to the LED and the current flowing through the LED may be related to the intensity (e.g., light quantity) of light emitted from the LED. The threshold voltage and / or forward voltage of the LED may vary depending on the light emitted through the LED. For example, the threshold voltage and / or forward voltage of an LED emitting red light may be lower than the threshold voltage and / or forward voltage of an LED emitting blue light.

[0025] In one embodiment, where the backlight panel (160) includes LEDs having different colors, applying the same voltage to the LEDs in the backlight panel (160) is inefficient in terms of power consumption, which is determined by the product of voltage and current. For example, since the first threshold voltage of an LED emitting blue light is higher than the second threshold voltage of an LED emitting red light, the red light-emitting LED may be driven at a voltage that exceeds the second threshold voltage (e.g., greater than or equal to the difference between the first threshold voltage and the second threshold voltage). In one embodiment, the display device (101) may apply different voltages (e.g., voltages suitable for driving each of the LEDs) to the LEDs in the backlight panel (160) having different colors. Since different voltages are applied to the LEDs in the backlight panel (160), the power efficiency (or power consumption) of the display device (101) including the backlight panel (160) may be improved.

[0026] FIGS. 2A and 2B are diagrams illustrating a backlight panel (160) included in a display device (e.g., display device (101) of FIG. 1) according to one embodiment. FIG. 2A illustrates one side (e.g., the front side and / or front side of the backlight panel (160)) of the backlight panel (160) as viewed from the display panel (e.g., display panel (150) of FIG. 1). A plurality of backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9, ...) may be arranged on the one side of the backlight panel (160). Although FIG. 2A illustrates nine backlight pixels, the number and / or positions of the backlight pixels included in the backlight panel (160) are not limited to the embodiment of FIG. 2A. FIG. 2a illustrates a backlight panel (160) having three backlight pixels arranged in a column direction, but the embodiment is not limited thereto.

[0027] A backlight pixel may include LEDs configured to emit light of primary colors included in white (e.g., red, green, and blue). In the present disclosure, a backlight pixel may be referred to as a set (or pair, or triplet) of LEDs. For example, each of a plurality of backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9, ...) included in the backlight panel (160) may include three LEDs configured to emit light of red, green, and blue, respectively. While a backlight pixel including three LEDs of different colors (e.g., a red LED, a green LED, and a blue LED) is illustrated as an example, embodiments of the present disclosure are not limited to the above example(s). For example, a backlight pixel may include more than three LEDs or less than three LEDs. For example, at least two LEDs within a backlight pixel may be configured to emit light of the same color.

[0028] Referring to FIG. 2A, on the backlight panel (160), LEDs included in each (respective) backlight pixel may be densely arranged. In order to clearly provide white light mixed with red, green, and blue, LEDs included in the backlight pixel may be densely arranged. For example, the distance and / or interval between LEDs included in a specific backlight pixel may be smaller than the distance and / or interval between LEDs included in each of different backlight pixels. Although FIG. 2A illustrates one embodiment in which LEDs included in a specific backlight pixel are arranged along a row direction (in a straight line or sequentially), the positional relationship of LEDs within the backlight pixel is not limited thereto.

[0029] FIG. 2A illustrates an embodiment in which a plurality of backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9, ...) included in a backlight panel (160) are arranged in a grid form, but the positional relationship of the plurality of backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9, ...) is not limited thereto. Referring to FIG. 2A, the backlight pixels (bp1, bp2, bp3) may be arranged along the column direction (or the vertical direction of the backlight panel (160)). Referring to FIG. 2A, the backlight pixels (bp1, bp4, bp7) may be arranged along the row direction (or the horizontal direction of the backlight panel (160)). The distances (or intervals) between the backlight pixels (bp1, bp2, bp3) arranged along the column direction may be equal to each other. The distances (or intervals) between the backlight pixels (bp1, bp4, bp7) arranged along the row direction may be equal to each other. Similarly, the intervals between the backlight pixels (bp1, bp2, bp3) in the column direction and the intervals between the backlight pixels (bp1, bp4, bp7) in the row direction may be equal to each other.

[0030] In one embodiment of FIG. 2A, where the LEDs within the backlight pixels are arranged in a straight line along the row direction, the orders of the red LEDs, green LEDs, and blue LEDs of the backlight pixels (bp1, bp2, bp3) arranged along the column direction may be the same. For example, if within the backlight pixel (bp1), the red LED, the green LED, and the blue LED are sequentially positioned along the column direction (e.g., FIG. 2A illustrates a direction from the left to the right of the sheet), within the backlight pixel (bp2) adjacent to the backlight pixel (bp1) along the column direction, the red LED, the green LED, and the blue LED may be sequentially positioned along the column direction.

[0031] In one embodiment, a circuit for controlling a plurality of backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9, ...) included in the backlight panel (160) may be integrally included in the backlight panel (160). In one embodiment, the circuit for controlling the plurality of backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9, ...) may be included in an electronic component and / or a printed circuit board (PCB) electrically connected to the backlight panel (160). The backlight panel (160) may include a plurality of backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9, ...) and may include one or more wires (or conductive wires, or wire segments, or cables) for connecting each of the plurality of backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9, ...) to the circuit.

[0032] FIG. 2B is a schematic block diagram of the backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6) of FIG. 2A, and a circuit for controlling the backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6). Referring to FIG. 2B, LEDs (red LEDs in the present disclosure) (dr1, dr2, dr3, dr4, dr5, dr6) configured to emit red light may be included in each of the backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6). Similarly, LEDs configured to emit green light (green LEDs in the present disclosure) (dg1, dg2, dg3, dg4, dg5, dg6) may be included in the backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6), respectively. Similarly, LEDs configured to emit blue light (blue LEDs in the present disclosure) (db1, db2, db3, db4, db5, db6) may be included in the backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6), respectively.

[0033] Referring to FIG. 2B, the backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6) may be connected to respective pixel control circuits (241, 242, 243, 244, 245, 246). For example, the backlight panel (160) and / or the display device including the backlight panel (160) may include a set (240) (or group) of pixel control circuits connected to respective backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6). For example, in order to control a backlight panel (160) including “n” backlight pixels, the backlight panel (160) may be electrically connected to n pixel control circuits. For example, the pixel control circuits and the backlight pixels may be connected in a 1:1 ratio. In the above example, if the backlight pixels include a red LED, a green LED, and a blue LED, a 1:3 connection can be established between the pixel control circuits and the LEDs of the backlight panel.

[0034] A pixel control circuit connected to a backlight pixel may be configured to receive at least one of a clock signal, a data signal, and a hold signal as a control signal for controlling the pixel control circuit. The source driving circuit (220) may be configured to transmit a control signal (e.g., a clock signal, a data signal, and / or a hold signal) to at least one pixel control circuit (e.g., a pixel control circuit included in a set (240)) for the at least one pixel control circuit to control at least one backlight pixel (or at least one LED included in the at least one backlight pixel). The source driving circuit (220) may be implemented as an electronic component connected to the backlight panel (160). Embodiments of the present disclosure are not limited to the above example(s), and the source driving circuit (220) may be implemented on a PCB included in the backlight panel (160).

[0035] A clock signal may be transmitted to a pixel control circuit to indicate a timing at which a hold signal, which is a digital signal, is to be received. For example, the timing may be indicated (or directed) by a rising edge or a falling edge of a waveform (e.g., a voltage and / or current waveform) of the clock signal. Referring to FIG. 2B, pixel control circuits (241, 242, 243) corresponding to backlight pixels (bp1, bp2, bp3) respectively may be connected to the source driving circuit (220) to receive a first clock signal (CLK1). Referring to FIG. 2B, pixel control circuits (244, 245, 246) corresponding to backlight pixels (bp4, bp5, bp6) positioned in the column direction respectively may be connected to the source driving circuit (220) to receive a second clock signal (CLK2). The source driving circuit (220) may be configured to transmit a data signal and / or a hold signal together with a clock signal (e.g., clock signals (CLK1, CLK2)) to at least one pixel control circuit.

[0036] The data signal may represent the brightness of an LED to be controlled by a pixel control circuit receiving the data signal. The data signal may be an analog signal representing the brightness based on current and / or voltage. Embodiments of the present disclosure are not limited to the above examples, and the data signal may be a digital signal representing the brightness of the LED. In a case where the data signal, which is an analog signal, is received, the pixel control circuit (e.g., pixel control circuits (241, 242, 243, 244, 245, 246) of FIG. 2B) may identify or determine a target current of an LED connected to the pixel control circuit by multiplying a current represented by the data signal by a specified multiple. In a case where the data signal, which is a digital signal, the pixel control circuit may identify the target current from a binary code represented by the data signal. The pixel control circuit can cause the LED to output light having a brightness indicated by the data signal by maintaining or changing the current of the LED at the target current. Referring to FIG. 2B, pixel control circuits (241, 242, 243) corresponding to each of the backlight pixels (bp1, bp2, bp3) can be configured to receive a first data signal (C1) from the source driving circuit (220). Pixel control circuits (244, 245, 246) corresponding to each of the backlight pixels (bp4, bp5, bp6) can be configured to receive a second data signal (C2) from the source driving circuit (220).

[0037] Referring to FIG. 2B, since all of the pixel control circuits (241, 242, 243) receive the first data signal (C1), in order to (individually) control the brightness of each of the pixel control circuits (241, 242, 243), the source driving circuit (220) can transmit a control signal (e.g., a first clock signal (CLK1) and / or a first hold signal (HOLD_ST1)) to the pixel control circuits (241, 242, 243) to inform the timing at which each of the pixel control circuits (241, 242, 243) receives the first data signal (C1). Similarly, since all of the pixel control circuits (244, 245, 246) receive the second data signal (C2), in order to control the brightness of each of the pixel control circuits (244, 245, 246), the source driving circuit (220) can transmit a control signal (e.g., a second clock signal (CLK2) and / or a second hold signal (HOLD_ST2)) to the pixel control circuits (244, 245, 246) to inform the timing at which each of the pixel control circuits (244, 245, 246) receives the second data signal (C2).

[0038] A hold signal may indicate a timing at which a pixel control circuit identifies or reads a data signal. A pixel control circuit, which receives a hold signal having a voltage (e.g., a high voltage) representing a designated digital value (e.g., 1), may identify or acquire a data signal while the hold signal maintains the voltage. Using the voltage and / or current of the identified data signal while the hold signal maintains the voltage, the pixel control circuit may identify or determine the brightness of an LED connected to the pixel control circuit. For example, the pixel control circuit may control the LED so that the LED maintains the identified brightness. For example, the pixel control circuit may output a current corresponding to the data signal to the LED, or control the LED so that a current indicated by the data signal flows to the LED. For example, the pixel control circuit may operate as a current source connected to the LED to determine the brightness of the LED (i.e., the intensity of light emitted from the LED). For example, the pixel control circuit can maintain the brightness of the LED at the identified brightness based on the AM (active matrix) method.

[0039] Referring to FIG. 2B, a first hold signal (HOLD_ST1) transmitted from a source driving circuit (220) may be sequentially transmitted (or relayed) to pixel control circuits (241, 242, 243) corresponding to each of the backlight pixels (bp1, bp2, bp3). Similarly, a second hold signal (HOLD_ST2) transmitted from a source driving circuit (220) may be sequentially transmitted (or relayed) to pixel control circuits (244, 245, 246) corresponding to each of the backlight pixels (bp4, bp5, bp6). HOLD_ST in FIG. 2B may mean “hold start.” For example, in a first time interval indicated by a first clock signal (CLK1), a pixel control circuit (241) that receives a first hold signal (HOLD_ST1) having a designated voltage (e.g., a voltage corresponding to a digital value 1) can transmit a first hold signal (HOLD_ST1) having the designated voltage to a pixel control circuit (242) connected (along the column direction) to the pixel control circuit (241) in a second time interval after the first time interval indicated by the first clock signal (CLK1). In the above example, the timings at which pixel control circuits (241, 242, 243) sequentially connected along the column direction receive the first hold signal (HOLD_ST1) having the designated voltage can be sequentially delayed according to the period (or frequency) of the first clock signal (CLK1).

[0040] A pixel control circuit corresponding to one (a) backlight pixel may be connected to cathodes of LEDs included in the backlight pixel. For example, a pixel control circuit (241) corresponding to a backlight pixel (bp1) may be connected to cathodes of a red LED (dr1), a green LED (dg1), and a blue LED (db1) of the backlight pixel (bp1), respectively. Referring to FIG. 2B, the pixel control circuit (241) may be connected to cathodes of the LEDs (dr1, dg1, db1) of the backlight pixel (bp1) via one (a) control line (or one (a) node).

[0041] Referring to FIG. 2B, a power circuit (230) may be configured to provide power to LEDs included in a backlight panel (160). The power circuit (230) may be included in an electronic component electrically connected to the backlight panel (160). Embodiments of the present disclosure are not limited to the above examples, and the power circuit (230) may be implemented on a PCB included in the backlight panel (160). The power circuit (230) may be connected to a plurality of power lines. The plurality of power lines may be included in one layer of the backlight panel (160) (e.g., one surface on which the LEDs are positioned) to connect the power circuit (230) and the LEDs within the backlight panel (160). Each of the plurality of power lines may be connected to a group (or set) of LEDs of a specific color. That is, a red LED, a green LED, and a blue LED may be connected to different power lines.

[0042] Referring to FIG. 2b, in one embodiment where the LEDs of the backlight pixels are arranged along the column direction, the pixel control circuit corresponding to the backlight pixel may be connected to all of the LEDs via a single control line extending along the column direction, and the power circuit (230) may be connected to the LEDs via each of a plurality of power lines positioned (parallel) along the row direction.

[0043] Referring to FIG. 2B, LEDs of the same color included in each of the plurality of backlight pixels (bp1, bp2, bp3) may be connected to a power circuit (230) via a single power line extending in the column direction. For example, the plurality of power lines connected to the power circuit (230) may include a first power line connected to a first group of LEDs (e.g., LEDs (dr1, dg1, db1, dr2, dg2, db2, dr3, dg3, db3)) having one (a) color (e.g., red) among the LEDs (e.g., LEDs (dr1, dr2, dr3)) included in the plurality of backlight pixels (e.g., backlight pixels (bp1, bp2, bp3)). Referring to FIG. 2B, anodes of the LEDs (dr1, dr2, dr3) may be connected to the first power line. The power circuit (230) can apply voltage (Vr1) to each of the LEDs (dr1, dr2, dr3) within the first group through the first power line.

[0044] For example, the plurality of power lines connected to the power circuit (230) may include a second power line connected to a second group of LEDs (e.g., LEDs (dg1, dg2, dg3)) having one (a) color (e.g., green) among the LEDs (e.g., LEDs (dr1, dg1, db1, dr2, dg2, db2, dr3, dg3, db3)) included in the plurality of backlight pixels (e.g., backlight pixels (bp1, bp2, bp3)). The power circuit (230) may apply a voltage (Vg1) different from the voltage (Vr1) to the second group of LEDs (dg1, dg2, dg3) through the second power line. For example, the power circuit (230) may apply a first voltage (e.g., voltage (Vr1)) for driving a red LED to a first power line connected to the red LED (e.g., LEDs (dr1, dr2, dr3)). For example, the power circuit (230) may apply a second voltage (e.g., voltage (Vb1)) for driving a blue LED to a third power line connected to the blue LED (e.g., LEDs (db1, db2, db3)). The first voltage and the second voltage may be different. For example, the second voltage for driving the blue LED may exceed the first voltage for driving the red LED. In the example, the power circuit (230) may apply a first voltage to the first power line, and may apply a second voltage exceeding the first voltage to the third power line. Similarly, the third voltage for driving the green LED may also be different from the first voltage and / or the second voltage.

[0045] For example, the plurality of power lines may include a third power line connected to a third group of LEDs (e.g., LEDs (db1, db2, db3)) having one (a) color (e.g., blue) among LEDs (e.g., LEDs (dr1, dg1, db1, dr2, dg2, db2, dr3, dg3, db3)) included in a plurality of backlight pixels (e.g., backlight pixels (bp1, bp2, bp3)). The power circuit (230) may apply a voltage (Vb1) different from the voltages (Vr1, Vg1) to the LEDs (db1, db2, db3) in the third group through the third power line.

[0046] Similarly, among the LEDs (dr4, dg4, db4, dr5, dg5, db5, dr6, dg6, db6) included in the backlight pixels (bp4, bp5, bp6), the red LEDs (dr4, dr5, dr6) may be (commonly) connected to a fourth power line. The plurality of power lines connected to the power circuit (230) may include a fifth power line connected to the anodes of the green LEDs (dg4, dg5, dg6) of the backlight pixels (bp4, bp5, bp6) positioned along one direction (e.g., a column direction) of the backlight panel (160). The power circuit (230) may include a sixth power line connected to the anodes of the blue LEDs (db4, db5, db6) of the backlight pixels (bp4, bp5, bp6). For example, in the sixth power line, blue LEDs (db4, db5, db6) can be connected in parallel to the power circuit (230). In summary, the power circuit (230) can be connected to power lines that are each connected to the anodes of the LEDs of the backlight panel (160).

[0047] Referring to FIG. 2B, the power circuit (230) and / or the source driving circuit (220) may be connected to the timing controller (210). The timing controller (210) may be implemented with electronic components different from the backlight panel (160). The embodiments of the present disclosure are not limited to the above examples, and the timing controller (210) may be at least partially included in the backlight panel (160). The timing controller (210) may be electrically (or operably) connected to the source driving circuit (220) and the power circuit (230). The timing controller (210) may transmit an electrical signal (e.g., a synchronization signal) to the source driving circuit (220) and the power circuit (230) for synchronizing the source driving circuit (220) and the power circuit (230). For example, the timing controller (210) may be configured to synchronize the timing at which the source driving circuit (220) transmits a control signal to the pixel control circuits and the timing at which the power circuit (230) transmits a power signal (e.g., a direct current (DC) signal for driving an LED) to at least one of a plurality of power lines.

[0048] In one embodiment, the timing controller (210) may be configured to control the source driver circuit (220) to set and / or adjust the amount of light emitted through the LEDs of the backlight panel (160). The timing controller (210) may be configured to calculate or obtain the amount of light using images and / or videos output through a display panel (e.g., the display panel (150) of FIG. 1). The amount of light (or a signal representing the amount of light) may be provided from other circuitry of the display device connected to the timing controller (210) (e.g., the main circuitry of the display device). Although FIG. 2B illustrates the timing controller (210) as a different block from the source driver circuit (220), embodiments of the present disclosure are not limited to the above examples. For example, the timing controller (210) may be included within the source driver circuit (220) as a part of the source driver circuit (220).

[0049] As described above, according to one embodiment, the LEDs of the backlight panel (160) of the display device may be connected to the pixel control circuits according to an m:n (e.g., m > n) relationship. In one embodiment of FIG. 2B, the LEDs and the pixel control circuits may be connected according to a 3:1 relationship. The LEDs may be controlled by a set (240) of pixel control circuits less than the number of the LEDs. Since the number of pixel control circuits is reduced, the display device including the pixel control circuits may be produced at a relatively low cost. Since the number of pixel control circuits is reduced, the length and / or number of wires required for production of the pixel control circuits and the backlight panel may also be reduced. For example, the production cost, production time, and / or yield of the display device may be improved.

[0050] Hereinafter, with reference to FIG. 3, the operation of a display device that time-divisionally controls a set (240) of pixel control circuits connected to LEDs in a backlight panel (160) having different colors to control the LEDs is described.

[0051] FIG. 3 is an exemplary timing diagram for explaining the driving time of LEDs of a backlight panel. The backlight panel of FIG. 3 may include the backlight panel (160) of FIG. 1, FIG. 2A, and / or FIG. 2B. Referring to FIG. 3, a timing diagram is shown for explaining the operation of a display panel (e.g., the display panel (150) of FIG. 1), a backlight panel under the display panel, LEDs (e.g., a red LED, a green LED, and a blue LED) included in a backlight pixel (e.g., any one of the backlight pixels (bp1, bp2, bp3, bp4, bp5, bp6, bp7, bp8, bp9) of FIG. 2A and / or FIG. 2B), and a pixel control circuit connected to the LEDs.

[0052] Referring to FIG. 3, frame images (311, 312, 313) displayed through a display panel are illustrated. The frame images (311, 312, 313) may be included in a video played back through the display device. The display device may sequentially display the frame images (311, 312, 313) according to a refresh rate expressed in frames per second (fps). For example, when displaying the frame images (311, 312, 313) at 120 fps (or 120 Hz), the display device may display the frame image (311) on the display panel within a time interval (310) having a length of 1 / 120 second (approximately 8.33 milliseconds). After the time interval (310), the display device may display another frame image (312) after the frame image (311) on the display panel.

[0053] Below, the operation of a display device displaying frame images (311, 312, 313) at 120 fps is exemplarily described, but the display device may operate at a different fps than 120 fps (e.g., 12 fps, 24 fps, 30 fps, 60 fps, or other suitable fps).

[0054] In one embodiment, within a time interval (310) during which a frame image (311) is displayed, a backlight pixel may be controlled to repeatedly emit light (e.g., white light) according to a cycle (e.g., 8.33 milliseconds / 16 = 0.52 milliseconds) having a length less than the time interval (310). For example, the backlight pixel may repeatedly emit light 16 or more times during a time interval (310) during which a frame image (311) is displayed. The number of times a backlight pixel emits light within a time interval (310) corresponding to one frame image (311) may be empirically determined depending on whether or not flickering (or distortion caused by the flickering) of light provided from the backlight pixel is perceptible.

[0055] Referring to FIG. 3, within a time interval (320) within a time interval (310), a backlight pixel may emit white light once. For example, the length of the time interval (320) may be approximately 0.52 milliseconds when the backlight pixel is set to repeatedly emit light 16 times within the time interval (310). Hereinafter, the operation of the display device within the time interval (320) may be described. Within another time interval after the time interval (320), the display device may operate similarly to the operation described based on the time interval (320).

[0056] As described above with reference to FIG. 2b, when a backlight pixel includes LEDs of different colors (e.g., a red LED, a green LED, and a blue LED) and a pixel control circuit (commonly) connected to the LEDs, the pixel control circuit can sequentially control the LEDs within a time interval (320) during which the backlight pixel emits white light once. Referring to FIG. 3, the time interval (320) can include a time interval (331) for the red LED, a time interval (332) for the green LED, and a time interval (333) for the blue LED.

[0057] In one embodiment of a display device operating according to the timing diagram of FIG. 3, LEDs of three backlight pixels (e.g., backlight pixels (bp1, bp2, bp3) of FIG. 2b), each of which is connected to three pixel control circuits (e.g., pixel control circuits (241, 242, 243) of FIG. 2b), are connected to a power circuit (e.g., power circuit (230) of FIG. 2b) via power lines corresponding to different colors, respectively. For example, it is assumed that the red LEDs of the backlight pixels (e.g., the red LEDs (dr1, dr2, dr3) of FIG. 2B) are connected to the power circuit via a first power line, the green LEDs of the backlight pixels (e.g., the green LEDs (dg1, dg2, dg3) of FIG. 2B) are connected to the power circuit via a second power line, and the blue LEDs of the backlight pixels (e.g., the blue LEDs (db1, db2, db3) of FIG. 2B) are connected to the power circuit via a third power line.

[0058] Since the threshold voltage required to activate the LEDs varies depending on the color of the LEDs, the voltage applied to each of the first power line to the third power line can be set (individually or independently) depending on the color of the LED(s) connected to the power line. For example, within the time period (331) of FIG. 3, the power circuit can apply a voltage (Vr1) (e.g., about 2 V) higher than the threshold voltage of the red LED to the first power line among the first power line to the third power line. Within the time period (332) of FIG. 3 (e.g., a time period (332) different from the time period (331)), the power circuit (230) can apply a voltage (Vg1) (e.g., about 2.2 V) higher than the threshold voltage of the green LED to the second power line among the first power line to the third power line. Within a time interval (333) of FIG. 3, the power circuit may apply a voltage (Vb1) greater than or equal to the threshold voltage of the blue LED (e.g., approximately 3.3 V) to the third power line among the first to third power lines. For example, within each of the time intervals (331, 332, 333), the power circuit may exclusively transmit a power signal (e.g., a DC signal having a voltage greater than or equal to the threshold voltage) to any one of the power lines corresponding to each of the different colors. Referring to FIG. 3, within a time interval (333) in which the voltage (Vb1) is applied to the third power line, a voltage of substantially 0 V (or a voltage less than or equal to the threshold voltage) may be applied to the other power lines (or the remaining power lines) (e.g., OFF).

[0059] FIG. 3 illustrates the voltage of a clock signal (CLK) that a source driving circuit (e.g., the source driving circuit (220) of FIG. 2B) transmits to a set of pixel control circuits (e.g., the set (240) of FIG. 2B). Within a time period (331) in which a red LED is activated, the clock signal (CLK) may have six rising edges (e.g., rising edges at points c1, c2, c3, c4, c5, and c6). The pixel control circuit receiving the clock signal (CLK) may be configured to detect a data signal and / or a hold signal applied to the pixel control circuit at a time period in which a rising edge of the clock signal (CLK) is detected. Hereinafter, the operation of three pixel control circuits within a time period (331) for the red LED will be described.

[0060] Based on the above assumption, the clock signal (CLK) can be transmitted to three pixel control circuits (e.g., pixel control circuits 241, 242, 243 of FIG. 2b) connected along the column direction. Within the time period (331), the source driving circuit can transmit a hold signal (HOLD_ST1-1). Among the pixel control circuits, a first pixel control circuit (e.g., pixel control circuit 241 of FIG. 2b) directly connected to a source driving circuit (e.g., source driving circuit 220 of FIG. 2b) can receive the hold signal (HOLD_ST1-1) transmitted from the source driving circuit. The hold signal (HOLD_ST1-2 of FIG. 3) can represent a hold signal received by a second pixel control circuit connected to the first pixel control circuit. The hold signal (HOLD_ST1-3) of FIG. 3 may represent a hold signal received by the third pixel control circuit connected to the second pixel control circuit.

[0061] At a time point c1 within the time interval (331), based on a rising edge of a clock signal (CLK), the first pixel control circuit can receive a hold signal (HOLD_ST1-1). At a time point c1, the first pixel control circuit, which detects the hold signal (HOLD_ST1-1) having a designated voltage (e.g., a high voltage) indicating (or instructing) reception of a data signal, can receive a data signal (e.g., the first data signal (C1) of FIG. 2B) provided from the source driving circuit at a time point c1. The source driving circuit can transmit a data signal indicating the brightness of a red LED corresponding to the first pixel control circuit at the time point c1. Referring to FIG. 3, at a time point c1, the hold signals (HOLD_ST1-2, HOLD_ST1-3) received by the second pixel control circuit and the third pixel control circuit can have a voltage (e.g., a low voltage) different from the designated voltage. Therefore, at point c1, the second pixel control circuit and the third pixel control circuit do not identify or receive any data signal.

[0062] A first pixel control circuit that identifies a data signal at a time point c1 can control a red LED (e.g., a red LED (dr1) in FIG. 2B) connected to the first pixel control circuit during a time interval (340) having a length (Tled) after the time point c1. The first pixel control circuit can control the red LED so that a current indicated by the data signal flows to the red LED. For example, the first pixel control circuit can maintain the current of the red LED within at least a portion (e.g., the time interval (340)) of the time interval (331) for the red LED. For example, the first pixel control circuit can maintain the current of the red LED during the time interval (340) of the time interval (331) for the red LED so as to maintain the intensity of the red LED at an intensity related to a frame image (311) displayed through the display panel. The first pixel control circuit can include a capacitor for storing the data signal and / or the current indicated by the data signal. Within the above time period (340), the red LED connected to the first pixel control circuit can be activated based on the voltage (Vr1) applied from the first power line and the current controlled by the first pixel control circuit. For example, within the above time period (340), the red LED connected to the first pixel control circuit can emit red light based on the voltage (Vr1) and the current controlled by the first pixel control circuit.

[0063] A first pixel control circuit that receives a hold signal (HOLD_ST1-1) having a designated voltage indicating reception of a data signal at point c1 can transmit a hold signal (HOLD_ST1-2) having the designated voltage to a second pixel control circuit at a rising edge following point c1 (e.g., a rising edge at point c2).

[0064] Referring to FIG. 3, at time c2, based on the rising edge of the clock signal (CLK), the second pixel control circuit can receive or detect a hold signal (HOLD_ST1-2) having the specified voltage. The second pixel control circuit, which has received the hold signal (HOLD_ST1-2) having the specified voltage, can receive a data signal (e.g., the first data signal (C1) of FIG. 2B) provided from the source driving circuit at time c2. The source driving circuit can transmit a data signal indicating the brightness of a red LED (e.g., the red LED (dr2) of FIG. 2B) corresponding to the second pixel control circuit at time c2. Referring to FIG. 3, at time c2, the hold signals (HOLD_ST1-1, HOLD_ST1-3) received by the first pixel control circuit and the third pixel control circuit can have a voltage (e.g., a low voltage) different from the specified voltage. Therefore, at point c2, the first pixel control circuit and the third pixel control circuit do not identify any data signals. For example, at point c2, the first pixel control circuit can continue to control the red LED corresponding to the first pixel control circuit based on the data signal received at point c1 prior to point c2.

[0065] The second pixel control circuit, which has identified the data signal at the time point c2, can control a red LED (e.g., a red LED (dr2) in FIG. 2B) connected to the second pixel control circuit during a time interval (350) having a length (Tled) after the time point c2. The second pixel control circuit can include a capacitor for storing the current of the data signal, and can control the red LED using the current stored in the capacitor. For example, the second pixel control circuit can maintain the brightness of the red LED during the time interval (350) based on the brightness indicated by the data signal at the time point c2. The red LED connected to the second pixel control circuit can be activated during the time interval (350) based on the voltage (Vr1) applied to the first power line and the current controlled by the second pixel control circuit.

[0066] The second pixel control circuit, which has received a hold signal (HOLD_ST1-2) having a designated voltage indicating reception of a data signal at point c2, can transmit a hold signal (HOLD_ST1-3) having the designated voltage to the third pixel control circuit at a rising edge following point c2 (e.g., a rising edge at point c3).

[0067] Referring to FIG. 3, at time c3, based on the rising edge of the clock signal (CLK), the third pixel control circuit can receive a hold signal (HOLD_ST1-3) having the specified voltage. At time c3 when the third pixel control circuit detects the specified voltage of the hold signal (HOLD_ST1-3), the third pixel control circuit can receive a data signal (e.g., the first data signal (C1) of FIG. 2B) transmitted from the source driving circuit. At time c3, the source driving circuit can transmit a data signal indicating the brightness of a red LED (e.g., the red LED (dr3) of FIG. 2B) connected to the third pixel control circuit. At time c3, the hold signals (HOLD_ST1-1, HOLD_ST1-2) received by the first pixel control circuit and the second pixel control circuit can have a voltage (e.g., a low voltage) different from the specified voltage. Therefore, at time c3, the first pixel control circuit and the second pixel control circuit do not identify any data signal. For example, at point c3, the first pixel control circuit can continue to control the red LED corresponding to the first pixel control circuit based on the data signal received at point c1, and the second pixel control circuit can (continuously) control the red LED connected to the second pixel control circuit based on the brightness indicated by the data signal received at point c2.

[0068] At time c3, the third pixel control circuit that receives the data signal can activate a red LED (e.g., a red LED (dr3) in FIG. 2B) connected to the third pixel control circuit during a time interval (360) having a length (Tled) after time c3. The third pixel control circuit can include a capacitor for storing the current of the data signal. The third pixel control circuit can control the red LED using the current stored in the capacitor. For example, the third pixel control circuit can change or maintain the amount of current flowing to the red LED based on the brightness indicated by the data signal at time c3. The red LED connected to the third pixel control circuit can emit red light having a brightness indicated by the data signal at time c3 based on the voltage (Vr1) applied to the first power line and the current controlled by the third pixel control circuit during the time interval (360).

[0069] Referring to FIG. 3, within a time interval (331) for a red LED, the red LEDs connected to the first pixel control circuit to the third pixel control circuit can be activated during time intervals (340, 350, 360) of the same length (Tled). For example, the lengths of the time intervals (340, 350, 360) can be unified to the length (Tled) so that the red LEDs connected to the first pixel control circuit to the third pixel control circuit emit light of the same brightness.

[0070] Referring to FIG. 3, before the expiration of the time interval (331) for the red LED, the pixel control circuits can turn off the red LEDs connected to each of the pixel control circuits. For example, at a time point c4 after the time interval (340), a hold signal (HOLD_ST1-1) for deactivating (e.g., turning off) the red LED of the first pixel control circuit can be transmitted to the first pixel control circuit. At the rising edge of the time point c4, the first pixel control circuit, which has received the hold signal (HOLD_ST1-1) having a designated voltage indicating reception of a data signal, can receive a data signal provided from the source driving circuit at the time point c4. The source driving circuit can transmit a data signal representing a brightness (e.g., a brightness of substantially 0) for deactivating the LED (e.g., the red LED connected to the first pixel control circuit) at the time point c4. At the time point c4, the first pixel control circuit, which has received the data signal, can turn off the red LED connected to the first pixel control circuit.

[0071] At time c4, the first pixel control circuit, which has received a hold signal (HOLD_ST1-1) having a designated voltage indicating reception of a data signal, can transmit a hold signal (HOLD_ST1-2) having the designated voltage to the second pixel control circuit at a rising edge following time c4 (e.g., a rising edge at time c5). The second pixel control circuit can detect the hold signal (HOLD_ST1-2) having the designated voltage at time c5. Accordingly, at time c5, the second pixel control circuit can detect a data signal provided from the source driving circuit. The source driving circuit can transmit a data signal representing brightness that causes deactivation of the LED at time c5. Based on the data signal transmitted at time c5, the second pixel control circuit can turn off the red LED connected to the second pixel control circuit.

[0072] At time c5, the second pixel control circuit, which has received the hold signal (HOLD_ST1-2) having the specified voltage, can transmit the hold signal (HOLD_ST1-3) having the specified voltage to the third pixel control circuit at the rising edge following time c5 (e.g., the rising edge at time c6). At time c6, the third pixel control circuit, which has received the hold signal (HOLD_ST1-3) having the specified voltage, can control the red LED connected to the third pixel control circuit based on the data signal at time c6. When the source driving circuit transmits the data signal that makes the brightness of the LED substantially 0 at time c6, the third pixel control circuit can turn off the red LED at time c6.

[0073] Referring to FIG. 3, within the time interval (331) for the red LED, after point c4, all red LEDs connected to the three pixel control circuits can be (sequentially) deactivated. If an LED of a different color is turned on while the red LED is on, damage to the LED due to overvoltage and / or overcurrent may occur. To prevent such damage, from point c4, the three pixel control circuits can be (sequentially) reset.

[0074] Within a time period (331) for a red LED, an exemplary operation in which the first pixel control circuit to the third pixel control circuit control the red LEDs, respectively, has been described. Within a time period (332) for a green LED following the time period (331) for the red LED, the first pixel control circuit to the third pixel control circuit can control the green LEDs (e.g., the green LEDs (dg1, dg2, dg3) of FIG. 2B) connected to the first pixel control circuit to the third pixel control circuit, respectively, similar to the operation within the time period (331). Within the time period (332), the green LEDs can emit green lights based on a voltage (Vg1) applied to the second power line and a current controlled by the pixel control circuits (e.g., the first pixel control circuit to the third pixel control circuit) corresponding to each of the green LEDs. Within the time interval (332), since no voltage is applied to the power lines corresponding to the red LEDs and the blue LEDs (e.g., the first power line and / or the third power line), the red LEDs and the blue LEDs may be deactivated. Within the time interval (332), the green LEDs may emit the lights for a time interval of the same length. The start points (or end points) at which the green LEDs emit the lights may be different from each other due to the delay of the hold signal received by each of the first to third pixel control circuits. Within the time interval (332), the green LEDs and the pixel control circuits respectively connected to the green LEDs may be (sequentially) reset or deactivated.

[0075] Similarly, within a time interval (333) for the blue LED following a time interval (332) for the green LED, the first pixel control circuit to the third pixel control circuit may control the blue LEDs connected to the first pixel control circuit to the third pixel control circuit, respectively, similar to the operation within the time interval (331). Within the time interval (333), the blue LEDs may emit blue lights based on the voltage (Vb1) applied to the third power line and the current maintained by the pixel control circuits corresponding to each of the blue LEDs. Within the time interval (333), the red LEDs and the green LEDs may be turned off because no voltage is applied to the power lines (e.g., the first power line and / or the second power line) corresponding to the red LEDs and the green LEDs. The lengths of the time intervals during which the blue LEDs emit blue lights may be consistent with each other. Within the time interval (333), the blue LEDs and the pixel control circuits connected to each of the blue LEDs can be (sequentially) reset or deactivated.

[0076] Referring to FIG. 3, during a time period (320) which is a combination of time periods (331, 332, 333), since all of the red LEDs, green LEDs, and blue LEDs emit light, a user viewing a backlight panel including red LEDs, green LEDs, and blue LEDs can perceive a white color, which is a mixture of the lights, due to the afterimage of the light. When a display panel is positioned between the backlight panel and the user, a frame image (311) can be visualized as the white light is filtered by the display panel. While each of the other frame images (312, 313) following the frame image (311) is displayed, the backlight panel of the display device can repeatedly perform the operation performed within the time period (310) in which the frame image (311) was displayed.

[0077] In an exemplary case where a red LED, a green LED, and a blue LED of a backlight panel are connected to the same power line, since the threshold voltages for driving the red LED, the green LED, and the blue LED are different, the voltage applied to the power line can be set to a maximum value or higher of the threshold voltages. In the case, if the threshold voltage for driving the red LED is 2.0 V, the threshold voltage for driving the green LED is 2.2 V, and the threshold voltage for driving the blue LED is 3.3 V, then a voltage of 3.3 V must be applied to the power line so that all of the red LED, the green LED, and the blue LED can be activated. In the case, a voltage that is 1.3 V higher than the threshold voltage for driving the red LED can be applied to the red LED. In the case, a voltage that is 1.1 V higher than the threshold voltage for driving the green LED can be applied to the green LED.

[0078] In other words, within the above-described case, although the red LED and the green LED are activated at relatively low voltages, the red LED and the green LED receive relatively high voltages. Since the power consumption of an LED is the product of voltage and current, the power consumption of the red LED and the green LED receiving unnecessarily high voltages may inefficiently increase. Within the above case, the power consumption of the red LED, the green LED, and the blue LED can be calculated as shown in Table 1.

[0079]

[0080] Referring to Table 1, since the red LED, green LED, and blue LED all receive a voltage of 3.3 V and a current of 5 mA, the sum of the power consumption of the red LED, green LED, and blue LED can be 49.5 mW.

[0081] According to one embodiment, a display device may include a backlight panel including LEDs configured to emit light of different colors. To optimize power consumption of the LEDs, power to the LEDs may be separated according to the colors of the LEDs. As described above with reference to FIGS. 1 to 3 , the LEDs may be classified into groups of LEDs corresponding to one color, and power lines extending from a power circuit may be connected to each of the groups. The power circuit may apply different voltages to the power lines (e.g., power lines corresponding to different colors).

[0082] For example, since the red LED, green LED, and blue LED each receive different threshold voltages, even if the red LED, green LED, and blue LED receive 5 mA in Table 1, the sum of the power consumption of the red LED, green LED, and blue LED can be calculated as in Table 2.

[0083]

[0084] Comparing Tables 1 and 2, the power consumption when applying different voltages to the red LED, the green LED, and the blue LED may be less than the power consumption when applying the same voltages to the red LED, the green LED, and the blue LED. Comparing Tables 1 and 2, the power consumption may be reduced by about 24%. FIG. 4 is a graph (400) illustrating a color range that can be expressed by a display device according to one embodiment. FIG. 4 illustrates a graph (400) based on a two-dimensional mapping for a three-dimensional color space of red, green, and blue. The graph (400) may represent a color range that can be expressed by a display device (e.g., the display device (101) of FIG. 1) based on an XYZ color space (or CIE 1931 color space).

[0085] FIG. 4 is a graph (400) illustrating a color range that can be expressed by a display device according to one embodiment. FIG. 4 illustrates a graph (400) based on a two-dimensional mapping for a three-dimensional color space of red, green, and blue. The graph (400) can represent a color range that can be expressed by a display device (e.g., display device (101) of FIG. 1) based on an XYZ color space (or CIE 1931 color space).

[0086] Fig. 4 illustrates a color space (410) of sRGB. According to one embodiment, a red LED (e.g., red LEDs (dr1, dr2, dr3, dr4, dr5, dr6) of Fig. 2b) included in a backlight panel of a display device can output light of a color corresponding to a point (423) outside the color space (410) of sRGB. According to one embodiment, a green LED (e.g., green LEDs (dg1, dg2, dg3, dg4, dg5, dg6) of Fig. 2b) included in a backlight panel of a display device can output light of a color corresponding to a point (421) outside the color space (410). According to one embodiment, a blue LED included in a backlight panel of a display device (e.g., blue LEDs (db1, db2, db3, db4, db5, db6) of FIG. 2B) can output light of a color corresponding to a point (422) outside the color space (410).

[0087] Since the backlight panel includes LEDs that output lights having colors corresponding to points (421, 422, 423) outside the color space (410) of sRGB, a color space that can be expressed by a display device including the backlight panel may be wider than the color space (410) of sRGB. Referring to the graph (400) of FIG. 4, the display device can display colors included in the color space (420) of Rec. 2020 (or ITU-R Recommendation BT. 2020), which includes points (421, 422, 423). Embodiments of the present disclosure are not limited to the above examples. For example, the display device can display colors included in the color space of DCI-P3 (Digital Cinema Initiatives - P3). Since an image or video is displayed based on a color space wider than the color space (410) of sRGB, such as a color space (420), the color reproducibility of a display device including the backlight panel can be improved.

[0088] FIG. 5 is an exemplary flowchart for the operation of a display device according to one embodiment. The display device (101) of FIG. 1, the source driving circuit (220), the power circuit (230) of FIG. 2B, and / or the pixel control circuits (e.g., the pixel control circuits included in the set (240)) may perform the operations described with reference to FIG. 5. The order in which the operations (510, 520, 530) of FIG. 5 are performed is not limited to the order illustrated in FIG. 5. For example, the display device may perform the operations (510, 520, 530) in a different order than the order illustrated in FIG. 5.

[0089] Referring to FIG. 5, in operation (510), according to one embodiment, the display device may apply a first voltage to a first power line connected to LEDs of a first color during a first time period for controlling LEDs of a first color (e.g., red) of a backlight panel (e.g., backlight panel (160) of FIG. 2A and / or FIG. 2B). The first time period during which operation (510) is performed may correspond to time period (331) of FIG. 3. The first voltage of operation (510) may correspond to a threshold voltage for driving LEDs of the first color, such as voltage (Vr1) of FIG. 3. In operation (510), the display device may control a power circuit to apply the first voltage for driving the LED of the first color to the first power line connected to the LED of the first color among the power lines.

[0090] While applying a first voltage to a first power line based on operation (510), the display device can control pixel control circuits connected to LEDs of a first color to cause the LEDs of the first color to output lights of the first color. The pixel control circuits can be connected to the LEDs of the first color, the LEDs of the second color (e.g., green), and the LEDs of the third color (e.g., blue). Within a first time period during which operation (510) is performed, among the LEDs of the first color, the LEDs of the second color, and the LEDs of the third color, only the LEDs of the first color can output light because they receive the first voltage through the first power line.

[0091] Referring to FIG. 5, in operation (520), according to one embodiment, the display device may apply a second voltage (different from the first voltage) to a second power line connected to second color LEDs during a second time period for controlling second color (e.g., green) LEDs of a backlight panel. The second time period during which operation (520) is performed may correspond to time period (332) of FIG. 3. The second voltage of operation (520) may correspond to a threshold voltage for driving second color LEDs, such as voltage (Vg1) of FIG. 3. In operation (520), the display device may control a power circuit to apply the second voltage for driving the second color LED to the second power line connected to the second color LED among the power lines.

[0092] While applying a second voltage to the second power line based on operation (520), the display device can control pixel control circuits connected to the second color LEDs to cause the second color LEDs to output light of the second color. In one embodiment where the pixel control circuits are connected to all of the first color LEDs, the second color LEDs, and the third color LEDs, within the second time interval of operation (520), among the first color LEDs, the second color LEDs, and the third color LEDs, only the second color LED can receive the second voltage through the second power line. Accordingly, within the second time interval, among the first color LEDs, the second color LEDs, and the third color LEDs, only the second color LED can output light of the second color. For example, within the second time interval, the first color LEDs and the third color LEDs can be turned off.

[0093] Referring to FIG. 5, in operation (530), according to one embodiment, the display device may apply a third voltage, different from the first voltage and the second voltage, to a third power line connected to the third color LEDs during a third time period for controlling the third color LEDs (e.g., blue) of the backlight panel. The third time period during which operation (530) is performed may correspond to time period (333) of FIG. 3. The third voltage of operation (530) may correspond to a threshold voltage for driving the third color, such as voltage (Vb1) of FIG. 3. For example, each of the first voltage, the second voltage, and the third voltage of operations (510, 520, 530) may be set independently or may be different from each other. Within the operation (530), the display device can control the power circuit to apply the third voltage for driving the third color LED to the third power line connected to the third color LED among the power lines.

[0094] In one embodiment where the pixel control circuit is connected to all of the first color LED, the second color LED, and the third color LED, within the third time interval of operation (530), the pixel control circuit can control (selectively or exclusively) the third color LED. In one embodiment where the pixel control circuit is connected to all of the first color LED, the second color LED, and the third color LED, within the third time interval of operation (530), among the first color LED, the second color LED, and the third color LED, only the third color LED can receive the third voltage via the third power line. Accordingly, within the third time interval, among the first color LED, the second color LED, and the third color LED, only the third color LED can output light of the third color. For example, within the third time interval, the first color LED and the second color LED can be deactivated.

[0095] In one embodiment, a method may be required to reduce the power consumption of a display device (e.g., the power consumption of a backlight panel). In one embodiment, a method may be required to control the LEDs of the backlight panel using a simplified circuit. As described above, according to one embodiment, a display device (e.g., display device (101) of FIG. 1) may include a display panel (e.g., display panel (150) of FIG. 1), a backlight panel (e.g., backlight panel (160) of FIGS. 1, 2A, and / or 2B) including light emitting diodes (LEDs) arranged toward the display panel and configured to emit light having different colors, pixel control circuitry connected to cathodes of the LEDs (e.g., pixel control circuits (241, 242, 243, 244, 245, 246) of FIG. 2B), and a power circuitry connected to power lines respectively connected to anodes of the LEDs (e.g., power circuitry (230) of FIG. 2B). The power circuit may be configured to apply a first voltage for driving a first LED among the LEDs to a first power line connected to the first LED among the power lines. The power circuit may be configured to apply a second voltage for driving a second LED among the LEDs to a second power line connected to the second LED among the power lines. The second voltage may be different from the first voltage. According to one embodiment, a backlight panel of a display device may have reduced power consumption. According to one embodiment, a circuit for driving LEDs of a backlight panel of a display device may be simplified.

[0096] For example, the LEDs may include a first LED configured to emit red light (e.g., LEDs (dr1, dr2, dr3, dr4, dr5, dr6) of FIG. 2B), a second LED configured to emit blue light (e.g., LEDs (db1, db2, db3, db4, db5, db6) of FIG. 2B), and a third LED configured to emit green light (e.g., LEDs (dg1, dg2, dg3, dg4, dg5, dg6) of FIG. 2B).

[0097] For example, the power circuit may be configured to apply the second voltage, which exceeds the first voltage, to the second power line.

[0098] For example, the power circuit may be configured to apply the first voltage to the first power line within a first time interval. The power circuit may be configured to apply the second voltage to the second power line within a second time interval different from the first time interval.

[0099] For example, the pixel control circuit may be configured to maintain the current of the first LED within at least a portion of the first time interval.

[0100] For example, the pixel control circuit may be configured to maintain the current of the first LED so as to maintain the intensity of the first LED at an intensity related to a frame image displayed through the display panel, within at least a portion of the first time interval.

[0101] For example, the pixel control circuit may be connected to the cathodes of the LEDs via a (a) control line.

[0102] For example, the backlight panel may include a plurality of sets of LEDs, each set including the set of LEDs connected to the pixel control circuit. The display device may include a set of pixel control circuits, each set including the pixel control circuit. The pixel control circuit included in the set may be connected to each of the plurality of sets of LEDs.

[0103] According to one embodiment of the present invention, a display device as described above may include a display panel, a backlight panel including a plurality of backlight pixels, each of the plurality of backlight pixels including light emitting diodes (LEDs) arranged toward the display panel and configured to emit light having different colors, a set of pixel control circuits connected to each of the plurality of backlight pixels, and a power circuit connected to a plurality of power lines. The plurality of power lines may include a first power line connected to a first group of LEDs having a first color among the LEDs included in the plurality of backlight pixels, and a second power line connected to a second group of LEDs having a second color among the LEDs included in the plurality of backlight pixels. The power circuit may be configured to apply a first voltage to each of the LEDs in the first group via the first power line. The power circuit may be configured to apply a second voltage, different from the first voltage, to each of the LEDs in the second group via the second power line.

[0104] For example, each of the plurality of backlight pixels may include a first LED configured to emit red light, a second LED configured to emit blue light, and a third LED configured to emit green light.

[0105] For example, the power circuit may be configured to apply the first voltage to the first group of LEDs configured to emit red light. The power circuit may be configured to apply the second voltage, which exceeds the first voltage, to the second group of LEDs configured to emit blue light.

[0106] For example, the power circuit may be configured to apply the first voltage to the first power line within a first time interval. The power circuit may be configured to apply the second voltage to the second power line within a second time interval different from the first time interval.

[0107] For example, each pixel control circuit included in the set may be configured to maintain current in each of the LEDs included in the first group within at least a portion of the first time interval.

[0108] For example, the plurality of power lines may include a third power line connected to a third group of LEDs having a third color among the LEDs included in the plurality of backlight pixels. The power circuit may be configured to apply a third voltage, different from the first voltage and the second voltage, to the third power line within a third time interval that is different from the first time interval and the second time interval.

[0109] For example, each pixel control circuit included in the set may be connected to the cathodes of LEDs included in the corresponding backlight pixel via a control line (a).

[0110] In one embodiment, a method of a display device may be provided. The display device may include a backlight panel including light emitting diodes (LEDs) configured to emit light having different colors, a pixel control circuit connected to cathodes of the LEDs, and a power circuit connected to power lines respectively connected to anodes of the LEDs. The method may include an operation of controlling the power circuit to apply a first voltage for driving a first LED among the LEDs to a first power line connected to the first LED among the power lines. The method may include an operation of controlling the power circuit to apply a second voltage for driving a second LED among the LEDs to a second power line connected to the second LED among the power lines. The second voltage may be different from the first voltage.

[0111] For example, the LEDs may include a first LED configured to emit red light, a second LED configured to emit blue light, and a third LED configured to emit green light.

[0112] For example, the operation of controlling the power circuit may include an operation of controlling the power circuit to apply the second voltage, which exceeds the first voltage, to the second power line.

[0113] For example, the operation of controlling the power circuit may include an operation of controlling the power circuit to apply the first voltage to the first power line within a first time interval. The operation of controlling the power circuit may include an operation of controlling the power circuit to apply the second voltage to the second power line within a second time interval different from the first time interval.

[0114] For example, the pixel control circuit may be configured to maintain the current of the first LED within at least a portion of the first time interval.

[0115] As used herein, the term "if" will be understood to mean "when, upon," "in response to determining," or "in response to detecting," depending on the context. Similarly, "if it is determined to," or "if [the stated condition or event] is detected," will optionally be understood to mean "upon determining," or "in response to determining," "upon detecting [the stated condition or event]," or "in response to detecting [the stated condition or event]."

[0116] The devices described above may be implemented as hardware components, software components, and / or a combination of hardware components and software components. For example, the devices and components described in the embodiments may be implemented using one or more general-purpose computers or special-purpose computers, such as a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), a programmable logic unit (PLU), a microprocessor, or any other device capable of executing instructions and responding to them. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to the execution of the software. For ease of understanding, the processing device is sometimes described as being used alone; however, one of ordinary skill in the art will recognize that the processing device may include multiple processing elements and / or multiple types of processing elements. For example, a processing unit may include multiple processors, or a processor and a controller. Other processing configurations, such as parallel processors, are also possible.

[0117] Software may include a computer program, code, instructions, or a combination of one or more of these, which may configure a processing device to perform a desired operation or may independently or collectively command the processing device. The software and / or data may be embodied in any type of machine, component, physical device, computer storage medium, or device for interpretation by the processing device or for providing instructions or data to the processing device. The software may also be distributed over networked computer systems and stored or executed in a distributed manner. The software and data may be stored on one or more computer-readable recording media.

[0118] The method according to the embodiment may be implemented in the form of program commands that can be executed through various computer means and recorded on a computer-readable medium. In this case, the medium may be one that continuously stores a computer-executable program or one that temporarily stores it for execution or download. In addition, the medium may be various recording means or storage means in the form of a single or multiple hardware combinations, and is not limited to a medium directly connected to a computer system, but may also be distributed over a network. Examples of the medium may include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical recording media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, and those configured to store program commands, including ROM, RAM, and flash memory. In addition, examples of other media may include recording media or storage media managed by app stores that distribute applications, sites that supply or distribute various software, servers, etc.

[0119] Although the embodiments described above have been described by way of limited examples and drawings, those skilled in the art will appreciate that various modifications and variations can be made based on the above teachings. For example, appropriate results can still be achieved even if the described techniques are performed in a different order than described, and / or components of the described systems, structures, devices, circuits, etc. are combined or combined in a different manner than described, or are replaced or substituted with other components or equivalents.

[0120] Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the claims described below.

Claims

1. In the display device (101), Display panel (150); A backlight panel (160) comprising light emitting diodes (LEDs) configured to emit lights of different colors, the LEDs including a first LED and a second LED; A pixel control circuit (241, 242, 243, 244, 245, 246) connected to the cathodes of the above LEDs; and Includes a power circuit (230) connected to power lines respectively connected to the anodes of the above LEDs, The above power circuit, Among the LEDs, a first voltage for driving the first LED is applied to a first power line connected to the first LED among the power lines, and Among the LEDs, a second voltage for driving the second LED is configured to be applied to a second power line connected to the second LED among the power lines, and The second voltage is different from the first voltage, Display device.

2. In claim 1, the LEDs further include a third LED, The above first LED (dr1, dr2, dr3, dr4, dr5, dr6) is configured to emit red light; The above second LED (db1, db2, db3, db4, db5, db6) is configured to emit blue light; and The third LED (dg1, dg2, dg3, dg4, dg5, dg6) is configured to emit green light. Display device.

3. In claim 2, the second voltage is: exceeding the first voltage, Display device.

4. In claims 1 to 3, the power circuit, Within the first time interval, the first voltage is applied to the first power line, and Further configured to apply the second voltage to the second power line within a second time interval different from the first time interval, Display device.

5. In claim 4, the pixel control circuit, Further configured to maintain the current of the first LED within at least a portion of the first time interval, Display device.

6. In claim 5, the pixel control circuit, Further configured to maintain the current of the first LED so as to maintain the intensity of the first LED at an intensity related to a frame image displayed through the display panel within at least a portion of the first time interval. Display device.

7. In claims 1 to 6, the pixel control circuit, (a) connected to the cathodes of the LEDs via a control line, Display device.

8. In claims 1 to 7, the LEDs, comprising a plurality of sets of LEDs, including a set of said LEDs, connected to said pixel control circuit; The above display device, Further comprising a set of pixel control circuits, including the pixel control circuit, and The pixel control circuit of the above pixel control circuit set is connected to each of the plurality of sets of the LEDs, Display device.

9. In the display device, display panel; A backlight panel comprising a plurality of backlight pixels, each pixel comprising light emitting diodes (LEDs) configured to emit light of different colors; a set of pixel control circuits connected to each of the plurality of backlight pixels; and A power circuit connected to a plurality of power lines, said plurality of power lines comprising: a first power line connected to a first group of LEDs having a first color among the LEDs of the plurality of backlight pixels; and a second power line connected to a second group of LEDs having a second color among the LEDs of the plurality of backlight pixels, and The above power circuit, A first voltage is applied to each of the LEDs of the first group through the first power line, and configured to apply a second voltage to each of the LEDs of the second group through the second power line, and The second voltage is different from the first voltage, Display device.

10. In claim 9, each of the LEDs of the plurality of backlight pixels, A first LED configured to emit red light; a second LED configured to emit blue light; and comprising a third LED configured to emit green light; Display device.

11. In claim 10, the first group of LEDs, configured to emit red light, and The second group of said LEDs is configured to emit said blue light, Display device.

12. In claims 9 to 11, the power circuit, Within the first time interval, the first voltage is applied to the first power line, configured to apply the second voltage to the second power line within a second time interval different from the first time interval; Display device.

13. In claim 12, each of the pixel control circuits of the set of pixel control circuits, configured to maintain the current of each of the LEDs of the first group of LEDs within at least a portion of the first time interval; Display device.

14. In claim 12, the plurality of power lines are: Among the LEDs of the plurality of backlight pixels, a third power line connected to a third group of LEDs having a third color, The above power circuit, Further configured to apply a third voltage to the third power line within a third time interval different from the first time interval and the second time interval, The third voltage is different from the first voltage and the second voltage, Display device.

15. In claims 9 to 14, each of the pixel control circuits of the set of pixel control circuits, (a) connected to the cathodes of the LEDs of the corresponding backlight pixels via a control line, Display device.

Images