Planar lighting device

Abstract

The present disclosure is applicable to the technical field related to display devices, and, for example, relates to a planar lighting device using a light-emitting diode (LED). According to one embodiment of the present disclosure, the planar lighting device, which is driven by local dimming data supplied in units of frames, may comprise: a light-emitting element array including a plurality of blocks including a first block and a second block that include a plurality of light-emitting elements and are individually driven; a power source unit connected in parallel to the first block and the second block so as to supply power to the light-emitting element array; and a driving unit connected to each of the first block and the second block so as to drive the light-emitting element array such that power is temporally divided within a unit frame and supplied from the power source unit to the first block and the second block.

Description

Flat lighting device

[0001] The present disclosure is applicable to the technical field related to display devices, and relates to, for example, a flat lighting device using an LED (Light Emitting Diode).

[0002] In recent years, display devices with superior characteristics, such as thinness and flexibility, have been developed in the field of display technology. Currently, the major commercially available displays are represented by LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diode).

[0003] LCDs typically do not emit light on their own, so a backlight must be used to display images. This backlight consumes significant power because it constantly illuminates, regardless of the input video signal. Furthermore, LCD panels have low transmittance even when fully open, and even when completely blocked, backlight leakage can occur, resulting in poor image quality.

[0004] To address these issues, local dimming has been studied. A large number of light-emitting elements (e.g., LEDs) are arranged to form a flat lighting device, such as a backlight unit. The backlight unit is then subdivided into multiple local dimming blocks, allowing each block to be individually driven to suit the image.

[0005] At this time, since the number of local dimming blocks must increase to improve resolution, the number of control channels (drive units) for controlling the local dimming blocks may also increase accordingly. Therefore, control channels corresponding to the number of local dimming blocks may be required, which may increase manufacturing costs. Generally, the number of control channels equal to the number of local dimming blocks is required.

[0006] Meanwhile, as the number of local dimming blocks increases, the number of control channels also increases, and consequently, the number of connection lines connecting the local dimming blocks and the control channels may also increase. Consequently, the board implementing the control channel may increase in size, and the number of connection connectors and connection lines may also increase, leading to increased manufacturing costs and design constraints.

[0007] Therefore, a solution to these problems is required.

[0008] The technical problem to be solved by the present disclosure is to provide a flat lighting device capable of controlling two local dimming blocks using one control channel unit.

[0009] Accordingly, it is intended to provide a flat lighting device in which half the number of control channels of local dimming blocks can be configured.

[0010] According to one embodiment of the present disclosure, a flat lighting device driven by local dimming data supplied in units of frames may include: a light emitting element array including a plurality of blocks, each block including a first block and a second block, each block individually driven; a power supply connected in parallel to the first block and the second block to supply power to the light emitting element array; and a driving unit connected to each of the first block and the second block to drive the light emitting element array such that power is supplied from the power supply to the first block and the second block in a time-separated manner within a unit frame.

[0011] According to one embodiment of the present disclosure, a flat lighting device driven by local dimming data supplied on a frame basis may include a light emitting element array including a plurality of blocks, including a first block and a second block that include a plurality of light emitting elements and are individually driven in pairs, and a third block and a fourth block that are individually driven in pairs; a power supply unit that is connected in parallel to the first block to the fourth block and supplies power to the light emitting element array; a first driving unit that is connected to each of the first block and the second block and drives the light emitting element array such that power is supplied from the power supply to the first block and the second block in a time-separated manner within a unit frame; and a second driving unit that is connected to each of the third block and the fourth block and drives the light emitting element array such that power is supplied from the power supply to the third block and the fourth block in a time-separated manner within a unit frame.

[0012] According to one embodiment of the present disclosure, a flat lighting device driven by local dimming data supplied in units of frames may include a light emitting element array including a first block and a second block each of which includes a plurality of light emitting elements and is driven individually; a power supply unit connected in parallel to the first block and the second block to supply power to the light emitting element array; a first switching element and a second switching element that apply a driving current to the first block and the second block, respectively; a first transistor connected to the first switching element to switch the first block at a first timing; a second transistor connected to the second switching element to switch the second block at a second timing different from the first timing; and a driving unit connected to each of the first block and the second block to drive the light emitting element array such that power is supplied from the power supply unit to the first block and the second block in a time-separated manner within a unit frame.

[0013] According to one embodiment of the present disclosure, the following effects are achieved.

[0014] First, the duty of the local dimming control signal can be divided to control two local dimming blocks using one control channel unit.

[0015] Manufacturing costs can be reduced because one control channel controls two local dimming blocks. In other words, half the number of control channels can be configured as local dimming blocks, and accordingly, the number of connection lines and connection connectors can be reduced by half.

[0016] Accordingly, the manufacturing cost of the backlight unit can be reduced and the degree of design freedom can be increased.

[0017] Furthermore, according to another embodiment of the present disclosure, there are additional technical effects not mentioned herein. Those skilled in the art will understand the full scope of the specification and drawings.

[0018] FIG. 1 is a block diagram of a flat lighting device according to one embodiment of the present disclosure.

[0019] FIG. 2 is a timing diagram showing a driving signal of a flat lighting device according to one embodiment of the present disclosure.

[0020] FIG. 3 is a timing diagram showing a signal applied to a first block and a signal applied to a second block of a flat lighting device according to one embodiment of the present disclosure.

[0021] FIG. 4 is a block diagram showing details of a control channel section of a flat lighting device according to one embodiment of the present disclosure.

[0022] FIG. 5 is a block diagram showing details of a block mask portion of a flat lighting device according to one embodiment of the present disclosure.

[0023] FIG. 6 is a timing diagram showing the operation of a block mask portion of a flat lighting device according to one embodiment of the present disclosure.

[0024] FIG. 7 is a block diagram showing details of a data generation unit of a flat lighting device according to one embodiment of the present disclosure.

[0025] FIG. 8 is a timing diagram showing the operation of a data generation unit of a flat lighting device according to one embodiment of the present disclosure.

[0026] FIG. 9 is a timing diagram showing an example of the operation of a flat lighting device according to one embodiment of the present disclosure.

[0027] FIG. 10 is a timing diagram showing another example of the operation of a flat lighting device according to one embodiment of the present disclosure.

[0028] FIG. 11 is an expanded block diagram of a planar lighting device according to one embodiment of the present disclosure.

[0029] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or similar components will be given the same reference numbers, and redundant descriptions thereof will be omitted. The suffixes "module" and "part" used for components in the following description are assigned or used interchangeably only for the convenience of writing the specification, and do not in themselves have distinct meanings or roles. In addition, when describing the embodiments disclosed in this specification, if it is determined that a specific description of a related known technology may obscure the gist of the embodiments disclosed in this specification, a detailed description thereof will be omitted. In addition, it should be noted that the attached drawings are only intended to facilitate easy understanding of the embodiments disclosed in this specification, and should not be construed as limiting the technical ideas disclosed in this specification by the attached drawings.

[0030] Furthermore, although each drawing is described for convenience of explanation, it is also within the scope of the present disclosure that a person skilled in the art may implement another embodiment by combining at least two or more drawings.

[0031] Additionally, when an element such as a layer, region or substrate is referred to as existing "on" another element, it will be understood that this may be directly on the other element, or that there may be intermediate elements in between.

[0032] The semiconductor light-emitting device mentioned in the specification includes LEDs, micro LEDs, etc., and may be used interchangeably.

[0033]

[0034] FIG. 1 is a block diagram of a flat lighting device according to one embodiment of the present disclosure.

[0035] Referring to FIG. 1, a flat lighting device (10) according to one embodiment of the present disclosure may include a light emitting element array (100) including a plurality of light emitting elements (D1 to D3) and a plurality of blocks (110, 120) each of which is individually driven.

[0036] For example, such a flat lighting device (10) may include a backlight unit. This backlight unit may provide a light source to a display device such as an LCD. For example, the backlight unit may be driven in a split manner depending on the screen of the display device. Hereinafter, a backlight unit will be specifically described as an example of the flat lighting device (10).

[0037] This type of split-drive operation can be referred to as local dimming. Local dimming refers to the split-drive operation of the screen. By dividing the backlight unit into multiple areas and linking their brightness to the video signal, the backlight is turned off or dimmed in areas corresponding to dark portions of the image, while brightness is increased in bright areas. This significantly improves contrast ratio and power consumption.

[0038] For example, the light emitting element array (100) may include a first block (110) and a second block (120) that are each individually driven.

[0039] Each block (110, 120) may include a plurality of light-emitting elements (D1 to D3). Here, three light-emitting elements (D1 to D3) are illustrated, but each block (110, 120) may include a smaller or larger number of light-emitting elements. These multiple light-emitting elements (D1 to D3) may be connected in series with each other within each block (110, 120).

[0040] The flat lighting device (10) may include a power supply (300) that supplies power to the light emitting element array (100). This power supply (300) may be connected to one side of each block (110, 120), for example, to the anode side of the light emitting elements (D1 to D3).

[0041] In this way, the power supply unit (300) can be connected in parallel to the first block (110) and the second block (120) to supply power to the light emitting element array (100).

[0042] The flat lighting device (10) may include a driving unit (200) that is connected to the first block (110) and the second block (120), respectively, and drives the light emitting element array (100) so that power is supplied to the first block (110) and the second block (120) from the power supply unit (300) in a time-divided manner within a unit frame.

[0043] A power supply unit (300) may be connected to one side of the block (110, 120), for example, the anode side of the light-emitting elements (D1 to D3), and a driving unit (200) may be connected to the other side of the block (110, 120), for example, the cathode side of the light-emitting elements (D1 to D3).

[0044] As a specific example, a switching element (Q1; hereinafter, referred to as the first switching element) to which a driving unit (200) is connected may be connected to the other side of the first block (110), for example, the cathode side of the light-emitting elements (D1 to D3) included in the first block (110). For example, the driving unit (200) may be connected to the gate terminal of the first switching element (Q1). For example, the driving unit (200) may be connected to the gate terminal of the first switching element (Q1) through a resistor (R1; hereinafter, referred to as the first resistor).

[0045] Likewise, a switching element (Q2; hereinafter, referred to as a second switching element) to which a driving unit (200) is connected may be connected to the other side of the second block (120), for example, the cathode side of the light-emitting elements (D1 to D3) included in the second block (120). For example, the driving unit (200) may be connected to a gate terminal of the second switching element (Q2). For example, the driving unit (200) may be connected to a gate terminal of the second switching element (Q2) through a resistor (R2; hereinafter, referred to as a second resistor).

[0046] The first switching element (Q1) and the second switching element (Q2) can be commonly connected to the driving unit (200). The driving unit (200) can supply a driving signal to each switching element (Q1, Q2) to supply a driving current to the light emitting elements (D1 to D3) included in each block (110, 120). In addition, a voltage (VLED) corresponding to the driving current can be supplied to the light emitting elements (D1 to D3).

[0047] Meanwhile, a transistor (S1; hereinafter, a first transistor) for switching the first block (110) at a first timing may be connected to the first switching element (Q1). A transistor (S2; hereinafter, a second transistor) for switching the second block (120) at a second timing may be connected to the second switching element (Q2).

[0048] These first transistor (S1) and second transistor (S2) can be connected to ground (GND). For example, the first transistor (S1) and the second transistor (S2) can be connected to ground (GND) through resistors (third resistor (R3) and fourth resistor (R4)), respectively.

[0049] The driving unit (200) can be commonly connected to the first transistor (S1) and the second transistor (S2). The driving unit (200) can be connected to the gate or base terminals of the first transistor (S1) and the second transistor (S2).

[0050] For example, the driving unit (200) may apply a driving signal to the first block (110) at a first timing within a unit frame. In addition, the driving unit (200) may apply a driving signal to the second block at a second timing excluding the first timing within the unit frame (see FIGS. 2 and 3). For example, the first timing and the second timing may correspond to timings that divide the unit frame time in half.

[0051] Fig. 2 is a timing diagram showing a driving signal of a planar lighting device according to one embodiment of the present disclosure. Fig. 3 is a timing diagram showing a signal applied to a first block and a signal applied to a second block of a planar lighting device according to one embodiment of the present disclosure.

[0052] Referring to FIGS. 2 and 3, a driving signal transmitted from a driving unit (200) may be divided and output according to a divided first timing (A) and a second timing (B). For example, a signal for driving a first block (110) may be applied during a first timing (A) during a unit frame (1 frame) time, and a signal for driving a second block (120) may be applied during a second timing (B).

[0053] At this time, the signal driving the first block (110) and the signal driving the second block (120) can be inverted from each other.

[0054] Referring to FIG. 3, a driving signal may be applied to the first block (110) during section A1 (first block operating section), and a driving signal may not be applied to the first block (110) during section A2 (first block non-operating section).

[0055] Meanwhile, a driving signal may not be applied to the second block (120) during the B1 section (second block non-operation section), and a driving signal may be applied to the second block (120) during the B2 section (second block operation section).

[0056] For this operation, the polarity of the first transistor (S1) and the second transistor (S2) may be opposite. For example, when using MOSFETs as transistors, the first transistor (S1) may be an N-MOSFET and the second transistor (S2) may be a P-MOSFET. Of course, conversely, the first transistor (S1) may be a P-MOSFET and the second transistor (S2) may be an N-MOSFET.

[0057] In this way, a driving signal based on the first local dimming data and a driving signal based on the second local dimming data can be applied to the first block (110) and the second block (120), respectively. Such a driving signal can be, for example, a PWM signal.

[0058] The first block (110) can be driven (powered) by brightness according to the first local dimming data. For example, a PWM signal corresponding to the first local dimming data can be applied to the first switching element (Q1) to drive the light-emitting elements (D1 to D3) included in the first block (110).

[0059] Similarly, the second block (110) can be driven (powered) by brightness according to the second local dimming data. For example, a PWM signal corresponding to the second local dimming data can be applied to the second switching element (Q2) to drive the light-emitting elements (D1 to D3) included in the second block (120).

[0060] Referring again to FIG. 1, the driving unit (210) may include a control channel unit (210) that is commonly connected to the first block (110) and the second block (120) to switch the driving signal, and a block switching unit (220) that controls the timing at which the driving signal is applied to the first block (110) and the second block (120).

[0061] For example, the control channel unit (210) can be commonly connected to the first switching element (Q1) and the second switching element (Q2) to apply a driving signal to the first block (110) and the second block (120).

[0062] In addition, the block switching unit (220) is commonly connected to the first transistor (S1) and the second transistor (S2) to control (switch) the timing at which a driving signal is applied to the first block (110) and the second block (120).

[0063] As described above, FIG. 1 shows a feature in which a light emitting element array (100) includes a pair of blocks, a first block (110) and a second block (120), which are connected to one control channel unit (210) and driven at different timings.

[0064] However, the light emitting element array (100) may include a plurality of blocks (local dimming blocks) that are connected to one control channel unit (210) and individually driven in pairs. For example, the light emitting element array (100) may include 2N blocks that are driven in pairs. These 2N blocks may be connected to N control channel units (see FIG. 11). That is, one pair of blocks may be driven by one control channel unit (210).

[0065] A flat lighting device such as a backlight unit is configured by arranging a large number of light-emitting elements (e.g., LEDs), and the backlight unit is divided into a number of local dimming blocks so that the local dimming blocks can be individually driven according to the image.

[0066] At this time, since the number of local dimming blocks must increase to improve resolution, the number of control channels (drive units) for controlling the local dimming blocks may also increase accordingly. Therefore, control channels corresponding to the number of local dimming blocks may be required, which may increase manufacturing costs. Generally, the number of control channels equal to the number of local dimming blocks is required.

[0067] Meanwhile, as the number of local dimming blocks increases, the number of control channels also increases, and consequently, the number of connection lines connecting the local dimming blocks and the control channels may also increase. Consequently, the board implementing the control channel may increase in size, and the number of connection connectors and connection lines may also increase, leading to increased manufacturing costs and design constraints.

[0068] However, according to one embodiment of the present disclosure described above, the duty of the local dimming control signal can be divided to control two local dimming blocks (the first block (110) and the second block (120)) using one control channel unit.

[0069] Manufacturing costs can be reduced because one control channel controls two local dimming blocks. In other words, half the number of control channels can be configured as local dimming blocks, and accordingly, the number of connection lines and connection connectors can be reduced by half.

[0070] Accordingly, the manufacturing cost of the backlight unit can be reduced and the degree of design freedom can be increased.

[0071]

[0072] FIG. 4 is a block diagram showing details of a control channel section of a flat lighting device according to one embodiment of the present disclosure.

[0073] Referring to FIG. 4, the control channel unit (210) may include a first signal generation unit (212) that generates a first driving signal by the first local dimming data of the first block (110) from a first receiving unit (211) that receives the first block LD data (local dimming data) for the first block (110).

[0074] The first signal generation unit (212) can generate a first driving signal based on the first local dimming data of the first block (110). This first driving signal may be a PWM signal. For example, the first driving signal may be a PWM signal applied to the first block (110) during the timing of half of a unit frame.

[0075] The control channel unit (210) may include a first data generation unit (213) that generates driving data according to the first driving signal. Here, the first data generation unit (213) may adjust the output time of the local dimming data received from the first receiving unit (211) to match the activation timing of each block (110, 120).

[0076] The control channel unit (210) may include a second signal generation unit (215) that generates a second driving signal by the second local dimming data of the second block (120) from a second receiving unit (214) that receives the second block LD data (local dimming data) for the second block (110).

[0077] The second signal generation unit (215) can generate a second driving signal based on the second local dimming data of the second block (120). This second driving signal may be a PWM signal. For example, the second driving signal may be a PWM signal applied to the second block (120) during the timing of the remaining half of the unit frame.

[0078] The control channel unit (210) may include a second data generation unit (216) that generates driving data according to the second driving signal. Here, the second data generation unit (216) may adjust the output time of the local dimming data received from the second receiving unit (214) to match the activation timing of each block (110, 120).

[0079] The control channel unit (210) may include a block mask unit (217) that generates a divided duty signal and transmits it to the block switching unit (220). The block mask unit (217) may generate a 50% duty signal for activating each of the first block (110) and the second block (120).

[0080]

[0081] Fig. 5 is a block diagram showing details of a block mask portion of a planar lighting device according to one embodiment of the present disclosure. Fig. 6 is a timing diagram showing the operation of a block mask portion of a planar lighting device according to one embodiment of the present disclosure.

[0082] Referring to FIG. 5, the block mask unit (217) may include a synchronization signal (Vsync) input unit (2171) into which a synchronization signal for a frame is input, and a clock input unit (2172) into which a reference clock signal is input. Here, the reference clock may be a PWM clock.

[0083] The block mask unit (217) may include a counter unit (2173) that counts by synchronizing the clock signal to a synchronization signal (Vsync).

[0084] Additionally, the block mask unit (217) may include a signal generator (2174) that divides the timing (the first timing and the second timing) according to the output of the counter unit (2173). Here, the signal generator (2174) may generate a 50% duty signal.

[0085] In this way, the block mask unit (217) can generate a 50% duty signal to activate the first block (110) and the second block (120), respectively, and provide it to each data generation unit (213, 216) of the control channel unit (210).

[0086] The signal generator (2174) can generate a block mask signal using a Vsync signal (synchronization signal) that indicates the start of a frame and a PWM generation clock for forming PWM data.

[0087] The counter unit (2173) receives a signal from the synchronization signal (Vsync) input unit (2171) and a signal from the clock input unit (2172), synchronizes to Vsync, counts the PWM clock, and transmits a 50% duty signal to the signal generator (2174).

[0088] The signal generator (2174) can receive a signal from the counter unit (2173) and generate a signal to activate the first block (110) and the second block (120), respectively.

[0089] In Fig. 6, A represents the operating section of the first block (110) and B represents the operating section of the second block (120).

[0090]

[0091] Fig. 7 is a block diagram showing details of a data generation unit of a flat lighting device according to one embodiment of the present disclosure. Fig. 8 is a timing diagram showing the operation of a data generation unit of a flat lighting device according to one embodiment of the present disclosure.

[0092] Referring to FIG. 7, each data generation unit (213, 216) may include a drive signal input unit (2131) for receiving a drive signal and a block mask input unit (2131) for receiving a block mask signal.

[0093] Each data generation unit (213, 216) may include a data delay unit (2133) that synchronizes a driving signal to the block mask signal. The data delay unit (2133) may synchronize the data of the first block (110) and the data of the second block (120) to each operation section (A, B).

[0094] In this way, the synchronized driving signal can be output through the output data output unit (2134).

[0095] Each data generating unit (213, 216) can provide a function for aligning the output timing of the local dimming data of the first block (110) and the local dimming data of the second block (120). That is, each data generating unit (213, 216) can enable the local dimming data of the first block (110) and the local dimming data of the second block (120) to be output without conflict.

[0096] The data delay unit (2133) receives signals from the drive signal input unit (2131) that receives PWM data (or DAC (digital-to-analogue converter) data in which a PWM signal is converted into an analog signal) generated from each data generation unit (213, 216) and the block mask input unit (2132) that receives signals generated from the block mask unit (217), thereby synchronizing the drive signal with the block mask signal.

[0097] The data output unit (2134) can have the function of outputting data synchronized to the block mask in the data delay unit (2133).

[0098] Each data generation unit (213, 216) can generate current control data synchronized to the multi-switching signal of the block switching unit (220) at low gray levels.

[0099] Each data generation unit (213, 216) can divide one control data into multiple data to be generated according to multiple sections (timings) so as to produce the same brightness for the entire frame.

[0100]

[0101] Fig. 9 is a timing diagram showing an example of the operation of a planar lighting device according to one embodiment of the present disclosure. Fig. 10 is a timing diagram showing another example of the operation of a planar lighting device according to one embodiment of the present disclosure.

[0102] The block switching unit (220) can generate a signal for current control for driving the first block (110) and a signal for current control for driving the second block (120) within one frame.

[0103] At this time, a 50% duty cycle can be used in the analog method using low current at low gray levels, but staining may occur.

[0104] When using the PWM method in low-grayscale environments, the turn-on time of the light-emitting element may be short, resulting in a relatively long afterglow time. Therefore, it may be difficult to maximize the afterglow effect. Therefore, as illustrated in FIG. 10, the operating period of the first block (110) and the operating period of the second block may be additionally divided within a single frame. This reduces the afterglow time. Consequently, the uniformity of the luminance of the light source may be improved.

[0105] In this way, the operating section of the first block (110) can be divided into two or more parts: the first timing and the second timing, which is the operating section of the second block (120). Fig. 10 illustrates an example where each timing is divided into two, but it is of course possible to divide it into more parts. Such an operation can be referred to as multi-switching.

[0106] In this way, during multi-switching operation, current control data can be generated from each data generation unit (213, 216) in sync with the output of the multi-block switching unit (220).

[0107] This type of multi-switching operation can be implemented in two-, three-, or four-part divisions, depending on the current data. In this way, as the number of multi-switching divisions increases, the afterglow time can be reduced, thereby improving the luminance uniformity of the light source.

[0108]

[0109] FIG. 11 is an expanded block diagram of a planar lighting device according to one embodiment of the present disclosure.

[0110] As mentioned above, the light emitting element array (100) may include a plurality of blocks (local dimming blocks) that are connected to one control channel unit (210) and individually driven in pairs.

[0111] For example, the light emitting element array (100) may include 2N blocks that are driven in pairs. These 2N blocks may be connected to N control channel units.

[0112] Referring to FIG. 11, a first control channel unit (210-1) may be configured to be connected with a pair of blocks (110-1, 110-2N). The first control channel unit (210-1) may be commonly connected with the first block (110-1) and the second block (110-2N), respectively. Similarly, the Nth control channel unit (210-N) may be commonly connected with the third block and the fourth block (not shown separately), respectively.

[0113] In this way, another pair of blocks can be connected and configured to the Nth control channel unit (210-N). That is, a pair of blocks can be driven by one control channel unit (210) or driving unit (200).

[0114] A flat lighting device such as a backlight unit is configured by arranging a large number of light-emitting elements (e.g., LEDs), and the backlight unit is divided into a number of local dimming blocks so that the local dimming blocks can be individually driven according to the image.

[0115] Each control channel unit (210-1 to 210-N) can be connected to and controlled by a pair of blocks (110-1, 110-2N) in the manner described above.

[0116]

[0117] The above description is merely an example of the technical idea of ​​the present disclosure, and those skilled in the art to which the present disclosure pertains may make various modifications and variations without departing from the essential characteristics of the present disclosure.

[0118] Accordingly, the embodiments disclosed in the present disclosure are intended to illustrate rather than limit the technical idea of ​​the present disclosure, and the scope of the technical idea of ​​the present disclosure is not limited by these embodiments.

[0119] The scope of protection of the present disclosure should be interpreted by the claims below, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the rights of the present disclosure.

[0120] According to the present disclosure, a flat lighting device and a display device using an LED (Light Emitting Diode) can be provided.

Claims

1. In a flat lighting device driven by local dimming data supplied in frame units, An array of light emitting elements comprising a plurality of blocks, each block including a first block and a second block, each block individually driven, each of which comprises a plurality of light emitting elements; A power supply unit connected in parallel to the first block and the second block to supply power to the light emitting element array; and A driving unit connected to each of the first block and the second block, and driving the light emitting element array so that power is supplied from the power unit to the first block and the second block in a time-separated manner within a unit frame. Flat lighting device.

2. In the first paragraph, the driving part Applying a driving signal to the first block at the first timing within the unit frame, Applying a driving signal to the second block at a second timing excluding the first timing within the unit frame Flat lighting device.

3. In the first paragraph, the first timing and the second timing are divided into two or more. Flat lighting device.

4. In the first paragraph, the first block and the second block each include light-emitting elements connected in series with each other, one side of which is connected to the power supply and the other side of which is connected to the driving unit. Flat lighting device.

5. In the first paragraph, the light emitting element array, A first switching element connected to the driving unit and applying a driving current to the first block; A first transistor connected to the first switching element for switching the first block at a first timing; A second switching element connected to the driving unit and applying a driving current to the second block; and A second transistor connected to the second switching element and configured to switch the second block at a second timing different from the first timing. Flat lighting device.

6. In the fifth paragraph, the first transistor and the second transistor have opposite polarities. Flat lighting device.

7. In the first paragraph, the driving unit, A control channel unit that is commonly connected to the first block and the second block and switches a driving signal; and A block switching unit that controls the timing at which the driving signal is applied to the first block and the second block. Flat lighting device.

8. In the 7th paragraph, the control channel unit Applying a driving signal to the first block at a first timing, and applying a driving signal to the second block at a second timing Flat lighting device.

9. In paragraph 7, the control channel unit A first signal generation unit that generates a first driving signal by first local dimming data for the first block; A first data generation unit that generates driving data according to the first driving signal; A second signal generation unit that generates a second driving signal by second local dimming data for the second block; A second data generation unit that generates driving data according to the second driving signal; and A block mask section that generates a divided duty signal and transmits it to the block switching section. Flat lighting device.

10. In the 9th paragraph, the block mask part, A synchronization signal input unit into which a synchronization signal for the above frame is input; A clock input section into which a clock signal is input; A counter unit that counts by synchronizing the clock signal with the synchronization signal; A signal generator that divides the timing according to the output of the counter section Flat lighting device.

11. In a flat lighting device driven by local dimming data supplied in frame units, An array of light-emitting elements comprising a plurality of blocks, each block comprising a first block and a second block, each block individually driven in pairs, and a third block and a fourth block, each block individually driven in pairs; A power supply unit connected in parallel to the first block to the fourth block to supply power to the light emitting element array; A first driving unit connected to the first block and the second block, respectively, and driving the light emitting element array so that power is supplied from the power unit to the first block and the second block in a time-separated manner within a unit frame; and A second driving unit connected to the third block and the fourth block, respectively, and driving the light emitting element array so that power is supplied from the power unit to the third block and the fourth block in a time-separated manner within a unit frame. Flat lighting device.

12. In the 11th paragraph, the driving unit Applying a driving signal to the first block at the first timing within the unit frame, Applying a driving signal to the second block at a second timing excluding the first timing within the unit frame Flat lighting device.

13. In the 12th paragraph, the first timing and the second timing are divided into two or more. Flat lighting device.

14. In a flat lighting device driven by local dimming data supplied in frame units, A light emitting element array comprising a first block and a second block each of which includes a plurality of light emitting elements and is individually driven; A power supply unit connected in parallel to the first block and the second block to supply power to the light emitting element array; A first switching element and a second switching element that apply a driving current to the first block and the second block, respectively; A first transistor connected to the first switching element for switching the first block at a first timing; A second transistor connected to the second switching element for switching the second block at a second timing different from the first timing; and A driving unit connected to each of the first block and the second block, and driving the light emitting element array so that power is supplied from the power unit to the first block and the second block in a time-separated manner within a unit frame. Flat lighting device.

15. In the 14th paragraph, the driving unit, A control channel unit that is commonly connected to the first switching element and the second switching element and applies a driving signal; and A block switching unit that is commonly connected to the first transistor and the second transistor and controls the timing at which the driving signal is applied. Flat lighting device.

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