KR20140003102A - Display apparatus - Google Patents

Abstract

The present invention relates to a display apparatus. According to the present invention, the display apparatus includes a display panel including an electrode and displaying an image, and a driving part supplying a driving signal for displaying the image to the electrode of the display panel. The driving part reduces the brightness of the display panel corresponding to the image data in a harsh condition mode. [Reference numerals] (AA) Number of sustain signals

Description

Display Apparatus [0001]

The present invention relates to a display device.

(PDP), Electro Luminescent Display (ELD), Vacuum Fluorescent Display (VFD), and the like have been developed in recent years in response to the demand for display devices. Display) have been studied and used. Among them, a liquid crystal panel of an LCD includes a TFT substrate and a color filter substrate which are opposed to each other with a liquid crystal layer and a liquid crystal layer interposed therebetween, and an image can be displayed using light provided from the backlight unit.

On the other hand, the conventional display device consumes a lot of power, and accordingly, a power supply unit (PSU) for providing high power is required, and thus, a manufacturing cost increases.

SUMMARY OF THE INVENTION An object of the present invention is to provide a display apparatus for adjusting luminance by using a histogram and current characteristics of input image data.

A display apparatus according to the present invention includes a display panel for displaying an image and including an electrode and a driver for supplying a driving signal for displaying an image to the electrode of the display panel, wherein the driver is adapted to the image data in a harsh condition mode. The luminance of the corresponding display panel may be reduced.

In the harsh condition mode, when the amount of change in the histogram of the image data is equal to or less than a preset reference time or more, and the current flowing through the switching element for supplying a driving signal to the electrode is equal to or greater than a preset threshold current. Can be set.

In addition, the display panel includes a front substrate on which scan electrodes and sustain electrodes are disposed, a rear substrate on which address electrodes intersecting the scan electrodes and sustain electrodes are disposed, and a partition wall partitioning a discharge cell between the front substrate and the rear substrate. Wherein the driver includes a data IC for supplying a data signal to the address electrode in an address period of a subfield, and the driver includes a sustain period after the address period of the subfield in the harsh condition mode. The number of sustain signals supplied to the scan electrode and the sustain electrode can be reduced.

In addition, the data IC may correspond to the switching device.

The average picture level (APL) of the first frame (Frame 1) and the second frame (Frame 2) of the image data is the same, and between the discharge cells adjacent in the vertical direction in the first frame When the number of changes of the data is greater than the number of changes of the data between discharge cells adjacent in the vertical direction in the second frame, the total number of the sustain signals allocated to the first frame is allocated to the second frame. It may be less than the total number of the sustain signals.

The image data according to the first frame may be image data supplied in the harsh condition mode, and the image data according to the second frame may be image data supplied in a normal mode.

The display panel may further include a backlight unit that emits light, and the display panel may include a front substrate and a rear substrate disposed to face each other, and a liquid crystal layer disposed between the front substrate and the rear substrate. The driver may include a data IC supplying a data signal to a data line formed in the display panel, and the driver may reduce power supplied to the backlight unit in the harsh condition mode.

The average picture level (APL) of the first frame (Frame 1) and the second frame (Frame 2) of the image data is the same, and between the adjacent cells in the vertical direction in the first frame When the number of changes of data is greater than the number of changes of the data between cells adjacent in the vertical direction in the second frame, the luminance of light emitted by the backlight unit in the first frame is determined by the backlight unit in the second frame. The light emitted may be smaller than the luminance.

The image data according to the first frame may be image data supplied in the harsh condition mode, and the image data according to the second frame may be image data supplied in a normal mode.

In addition, the greater the current flowing through the switching element for supplying the driving signal to the electrode in the harsh condition mode, the greater the decrease in luminance of the display panel corresponding to the image data.

The display device according to the present invention has the effect of reducing power consumption and manufacturing cost by adjusting the brightness of the image using histogram and current characteristics of the image data.

1 to 4 are views for explaining the configuration of the plasma display device and the image display method;
5 to 28 are views for explaining the driving method in the harsh condition mode;
29 to 39 are views for explaining the case where the present invention is applied to a liquid crystal display device; And
40 is a view for explaining the configuration of a broadcast signal receiver to which the display device according to the present invention is applied.

Hereinafter, a display device according to the present invention will be described in detail with reference to the accompanying drawings.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood that the present invention is not intended to be limited to the specific embodiments but includes all changes, equivalents, and alternatives falling within the spirit and scope of the present invention.

In describing the present invention, terms such as first and second may be used to describe various components, but the components may not be limited by the terms. The terms may only be used for the purpose of distinguishing one element from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

The term " and / or " may include any combination of a plurality of related listed items or any of a plurality of related listed items.

When an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may be present in between Can be understood. On the other hand, when it is mentioned that an element is "directly connected" or "directly connected" to another element, it can be understood that no other element exists in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions may include plural expressions unless the context clearly dictates otherwise.

In the present application, the terms "comprises", "having", and the like are used interchangeably to designate one or more of the features, numbers, steps, operations, elements, components, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries can be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are, unless expressly defined in the present application, interpreted in an ideal or overly formal sense .

In addition, the following embodiments are provided to explain more fully to the average person skilled in the art. The shapes and sizes of the elements in the drawings and the like can be exaggerated for clarity.

Hereinafter, a plasma display panel (Plasma Display Panel, Panel) is described as an example for the display panel, but the display panel applicable to the present invention is not limited to the liquid crystal panel, liquid crystal panel (Liquid Crystal Display Device, LCD), field emission display panel (FED), and organic light emitting display panel (OLED).

1 to 4 are views for explaining the configuration of the plasma display device and the image display method.

Referring to FIG. 1, the plasma display apparatus may include a plasma display panel 100 and a driver 110.

The plasma display panel 100 may include a first electrode and a second electrode crossing the first electrode. In addition, the plasma display panel 100 may implement an image in a frame including a plurality of subfields. Here, the first electrode may include the scan electrode Y and the sustain electrode Z, and the second electrode may be the address electrode X.

The driver 110 supplies a driving signal to at least one of the scan electrode (Y), the sustain electrode (Z), or the address electrode (X) of the plasma display panel 100, thereby realizing an image on the screen of the plasma display panel 100. You can do that. Preferably, the driving unit 110 may reduce the luminance of the plasma display panel 100 corresponding to the image data in the harsh condition mode. This will be described in more detail below.

Here, in FIG. 1, only the case in which the driving unit 110 is formed in one board form is illustrated, but in the present invention, the driving unit 110 is divided into a plurality of board forms according to electrodes formed on the plasma display panel 100. It is also possible to lose. For example, the driver 110 may include a first driver (not shown) for driving the scan electrode of the plasma display panel 100, a second driver for driving the sustain electrode, and a third driver (not shown) for driving the address electrode. Can be divided into

As shown in FIG. 2, the plasma display panel 100 includes a rear substrate on which a plurality of second electrodes 213 and X intersect the plurality of first electrodes 202 (Y) and 203 (Z). 211).

The discharge currents of the scan electrodes 202 and the sustain electrodes 203 and the sustain electrodes 203 are applied to the front substrate 201 on which the scan electrodes 202 and the sustain electrodes 203 and the sustain electrodes Z are formed. ) And the sustain electrodes 203, Z may be disposed on the lower dielectric layer 204. In this case,

The front substrate 201 on which the upper dielectric layer 204 is formed may be provided with a protective layer 205 for facilitating discharge conditions. The protective layer 205 may include a material having a high secondary electron emission coefficient, for example, a magnesium oxide (MgO) material.

Address electrodes 213 and X are formed on the rear substrate 211 and address electrodes 213 and X are formed on the rear substrate 211 on which the address electrodes 213 and X are formed. The lower dielectric layer 215 may be formed.

Barrier ribs 212 such as a stripe type, a well type, a delta type, and a honeycomb type for partitioning a discharge space, that is, a discharge cell, are formed on an upper portion of the lower dielectric layer 215 . Accordingly, a first discharge cell that emits red (R) light, a second discharge cell that emits blue (B) light, and a second discharge cell that emits green (Green) light are provided between the front substrate 201 and the rear substrate 211, : G) a third discharge cell that emits light, or the like.

The barrier rib 212 includes a first barrier rib 212b and a second barrier rib 212a. The height of the first barrier rib 212b and the height of the second barrier rib 212a may be different from each other.

On the other hand, in the discharge cell, the address electrode 213 may cross the scan electrode 202 and the sustain electrode 203. That is, the discharge cells are formed at the intersections of the address electrodes 213 with the scan electrodes 202 and the sustain electrodes 203.

A predetermined discharge gas may be filled in the discharge cells partitioned by the barrier ribs 212.

In addition, in the discharge cells partitioned by the barrier ribs 212, a phosphor layer 214 that emits visible light for image display upon address discharge may be formed. For example, a first phosphor layer for generating red light, a second phosphor layer for generating blue light, and a third phosphor layer for generating green light may be formed.

When a predetermined signal is supplied to at least one of the scan electrode 202, the sustain electrode 203, and the address electrode 213, a discharge may occur in the discharge cell. When a discharge is generated in the discharge cell, ultraviolet rays can be generated by the discharge gas filled in the discharge cell, and such ultraviolet rays can be irradiated to the phosphor particles of the phosphor layer 214. Then, the phosphor particles irradiated with the ultraviolet rays emit visible light, so that a predetermined image can be displayed on the screen of the plasma display panel 100.

3 illustrates an example of an image frame for implementing gradation of an image.

Referring to FIG. 3, a frame for implementing gray levels of an image may include a plurality of subfields SF1 to SF8.

In addition, the plurality of subfields may include a sustain period for implementing gradation according to an address period and a number of discharges for selecting discharge cells in which discharge cells will not occur or discharge cells in which discharge occurs. Period) may be included.

For example, in case of displaying an image with 256 gray levels, for example, one frame is divided into eight subfields SF1 to SF8 as shown in FIG. 3, and each of the eight subfields SF1 to SF8 is an address. It can include a period and a sustain period.

Alternatively, at least one subfield of the plurality of subfields of the frame may further include a reset period for initialization.

In addition, at least one subfield of the plurality of subfields of the frame may not include a sustain period.

On the other hand, the number of the sustain signals supplied in the sustain period may be adjusted to set the weight of the corresponding subfield. That is, a predetermined weight can be given to each subfield using the sustain period. For example, the weight of each subfield is 2 ⁿ by setting the weight of the first subfield to 2 ⁰ and the weight of the second subfield to 2 ¹ (where n = 0, 1, 2, 3, 4, 5, 6, 7) can be set to increase the ratio. By adjusting the number of the sustain signals supplied in the sustain period of each sub-field in accordance with the weight value in each sub-field, it is possible to implement various image gradations.

In FIG. 3, only one image frame is composed of eight subfields. However, the number of subfields constituting one image frame may be variously changed. For example, one video frame may be configured with 12 subfields from the first subfield to the twelfth subfield, or one video frame may be configured with 10 subfields.

In addition, in FIG. 3, subfields are arranged in an order of increasing weight in one image frame. Alternatively, subfields may be arranged in an order of decreasing weight in one image frame. Subfields may be arranged regardless.

At least one of the plurality of subfields included in the frame may be a selective erase subfield (SE), and at least one of the plurality of subfields may be a selective write subfield (SW). Do.

If one frame includes at least one selective erase subfield and an optional write subfield, the first subfield or the first and second subfields of the plurality of subfields of the frame are the selective write subfields, It may be desirable for the remainder to be selective erasure subfields.

4 illustrates an example of a driving waveform for driving a plasma display device. The driving waveform to be described below is supplied by the driving unit 110 of FIG. 1.

Referring to FIG. 4, in the reset period RP for initializing at least one subfield among a plurality of subfields of a frame, the reset signal RS is applied to the scan electrode Y. Can supply Here, the reset signal RS may include a rising ramp signal Ramp-Up RU whose voltage gradually increases and a falling ramp signal Ramp-Down RD whose voltage gradually falls.

For example, the rising ramp signal RU may be supplied to the scan electrode in the set-up period SU of the reset period, and the falling ramp signal RD may be supplied to the scan electrode during the set-down period SD after the set- .

When a rising ramp signal is supplied to the scan electrode, a weak dark discharge (i.e., setup discharge) occurs in the discharge cell due to the rising ramp signal. By this set-up discharge, the distribution of wall charges (Wall Charge) in the discharge cells can be made uniform.

When a falling ramp signal is supplied to the scan electrode after the rising ramp signal is supplied, a weak erase discharge (setdown discharge) occurs in the discharge cell. Due to the set-down discharge, wall charges can be uniformly left in the discharge cells to such an extent that address discharge can occur stably.

In the address period AP after the reset period, a scan reference signal Ybias having a voltage higher than the lowest voltage of the falling ramp signal may be supplied to the scan electrode.

In the address period, the scan signal Sc falling from the voltage of the scan reference signal Ybias may be supplied to the scan electrode.

As described above, when the scan signal is supplied to the scan electrode, the data signal Dt may be supplied to the address electrode X corresponding to the scan signal.

When such a scan signal and a data signal are supplied, a wall voltage due to wall charges generated in the reset period and a voltage difference between the scan signal and the data signal are added, and an address discharge may be generated in the discharge cell to which the data signal is supplied .

In addition, in the address period in which the address discharge occurs, the sustain reference signal Zbias may be supplied to the sustain electrode in order to effectively generate the address discharge between the scan electrode and the address electrode.

In the sustain period SP after the address period, the sustain signal SUS may be supplied to at least one of the scan electrode and the sustain electrode. For example, the sustain signal may be alternately supplied to the scan electrode and the sustain electrode.

When the sustain signal is supplied, the wall voltage in the discharge cell and the sustain voltage (Vs) of the sustain signal are added to the discharge cells selected by the address discharge. When the sustain signal is supplied, a sustain discharge is generated between the scan electrode and the sustain electrode Discharge may occur.

5 to 28 are views for explaining a driving method in the harsh condition mode. Hereinafter, the description of the parts described in detail above will be omitted.

Referring to FIG. 5, when image data is input (S500), a mode may be determined based on the input image data (S510).

In operation S520, it may be determined whether the input image data is in the severe condition mode, and in the case of the severe condition mode, the luminance of the display panel may be reduced in response to the image data (S530). In the following, the harsh condition mode may be referred to as a harsh mode.

A method of determining whether the input image data corresponds to the harsh condition mode is as described in FIG. 6.

Referring to FIG. 6, when image data is input (S500), a histogram of the input image data may be calculated (S600).

Subsequently, it may be determined whether the amount of change in the histogram of the image data input as a result of association of the histogram is equal to or less than the preset reference value during the preset reference time (S610).

As a result of the determination, when the amount of change in the histogram of the input image data is less than or equal to the reference value during the reference time, the driving current Ia corresponding to the input image data may be calculated (S620).

Thereafter, it may be determined whether the driving current Ia corresponding to the image data is greater than or equal to a preset threshold current (S630). Here, the driving current Ia may mean a current flowing through the switching element that supplies the driving signal to the electrode of the display panel.

As a result, when the driving current Ia corresponding to the image data is greater than or equal to a preset threshold current, the input image data may be determined as the image data corresponding to the severe condition mode, and the severe condition mode may be set (S640).

In addition, the luminance of the display panel may be reduced (S530) in response to the input image data.

If the amount of change in the histogram of the image data input as a result of the determination in step S610 is greater than the reference value during the reference time or when the driving current Ia corresponding to the image data input as the result of determination in the step S630 is smaller than the threshold current, the general Mode can be set (S650).

That is, the harsh condition mode is set when the amount of change in the histogram of the image data input for the preset reference time is less than or equal to the preset reference value, and the current flowing through the switching element that supplies the driving signal to the electrode of the display panel is greater than or equal to the preset threshold current. It may be desirable.

In the above description, a method of calculating the driving current Ia after calculating the histogram of the image data has been described as an example. However, differently, after calculating the driving current Ia corresponding to the image data, It may also be possible to compute histograms.

The method of calculating the change amount of the histogram during the reference time will be described in detail below.

Referring to FIG. 7, the histogram may represent frequency characteristics of gray levels in the image data. For example, if the maximum gradation of the image data is 1024 gradations, the frequency N2 of the A2 gradations smaller than 1024 gradations, the frequency N1 of the A1 gradations smaller than the A2 gradations, and the like can be confirmed by analyzing the histogram of the image data. .

In consideration of this, it is possible to check the difference in the frequency of use of gray scales in two frames by comparing the histograms of two consecutive frames.

Referring to FIG. 8, the histogram may be divided into a plurality of sections. For example, when the maximum gradation is 1024 gradations, the gradation 0 to gradation 128 is the first section (H1), the gradation 129 to gradation 256 is the second section (H2), and the gradation 257 to gradation 384 is the third section. (H3), gradation 385 to 512 512 for the fourth section (H4), gradation 513 to 640 for the fifth section (H5), gradation 641 to 768 for the sixth section (H6), gradation 769 to gradation Up to 896 may be divided into a seventh section H7 and a gradation 897 through gradation 1024 as an eighth section H8.

In addition, the change amount (difference) of the histogram between the continuous first frame F1 and the second frame F2 in each of the first to eighth periods H1 to H8 may be calculated.

For example, as in the case of FIG. 9, in the first section H1, the second frame F2 uses the gray level a1 as much as AR1 from the gray level 0 compared to the first frame F1, and uses the first frame F1. ) May use gray level a1 to gray level 128 as much as AR2 compared to the second frame F2. In other words, the usage amount of 0 to a1 gradations in the image according to the second frame F2 is as much as AR1 compared to the usage amount of 0 to a1 gradation in the image according to the first frame F1, and the first frame F1 The usage amount of a1 to 128 gradations in the image according to FIG. 1 may mean as much as AR2 compared to the usage amount of a1 to 128 gradations in the image according to the second frame F2.

Here, the change amount (difference) of the histogram between the first frame F1 and the second frame F2 continuous in the first section H1 may be AR1 + AR2.

In this way, the change amount (difference) of the histogram of the first frame F1 and the second frame F2 is calculated in each of the first to eighth sections H1 to H8, and the first frame is the sum of the calculated values. A change amount (difference) of the histogram between F1 and the second frame F2 may be obtained.

In addition, the reference time may include a plurality of frames. For example, as in the case of FIG. 10A, a total of eight frames from the first frame F1 to the eighth frame F8 are logically set as one frame group, and the frame group is referred to as a reference time. It is possible to set.

In this case, the amount of change in the histogram can be calculated in eight frames included in one frame group. For example, the first frame F1 and the second frame F2 are compared to calculate how much the histogram is changed in the second frame F2 compared to the first frame F1, and then the second frame F2. ) And the third frame F3, and compare two consecutive frames in this manner to calculate the amount of change in the total histogram (A1 + A2 + A3 + A4 + A5 + A6 + A7) within one frame group. Can be obtained.

The total histogram variation is less than or equal to the preset reference value within one frame group obtained by calculating in this manner, that is, during the reference time, and the current flowing through the switching element that supplies the drive signal to the electrode of the display panel is equal to or greater than the preset threshold current. In this case, it may be desirable to set the harsh condition mode.

As such, when eight frames are set as the reference time (frame group), it is necessary to delay the image data by at least eight frames in order to determine whether the corresponding image data corresponds to the severe condition mode. In this case, the image viewed by the viewer using the display device according to the present invention is image data of at least 8 frames earlier.

Alternatively, as in the case of FIG. 10B, it is possible to set a total of 16 frames from the first frame F1 to the sixteenth frame F16 as the reference time. In other words, it may be possible to logically set a total of 16 frames from the first frame F1 to the sixteenth frame F16 into one frame group. In this case, the amount of change in the histogram can be calculated in a total of 16 frames.

Alternatively, in the present invention, it is possible to calculate the amount of change in the histogram of the image data for a predetermined time, for example, 30 seconds (Sec), and enter the harsh condition mode according to the calculation result. In this case, 30 seconds (Sec) may be the reference time.

The above-described method for calculating the change amount of the histogram and the length of the reference time are examples of the present invention, and the present invention is not limited to the above contents. For example, the reference time can be set to two frames.

Hereinafter, the driving current Ia will be described in detail.

The driving current Ia may mean a current flowing through a switching element that supplies a driving signal to an electrode of the display panel.

The switching element may be a data IC supplying a data signal Dt to the address electrode X of the plasma display panel.

As shown in FIG. 11, the data IC 1000 includes a first switch S1 and a second switch S2 disposed in series between a data voltage source supplying a data voltage Vd and a ground GND. can do.

In addition, the data IC 1000 may be connected to the address electrode X at a node Na between the first switch S1 and the second switch S2.

The current flowing through the data IC 1000 during the driving may be referred to as the driving current Ia. For example, the current flowing through the first switch S1 of the data IC 1000 at the time of driving can be referred to as the driving current Ia.

The data IC 1000 may supply a data signal to the address electrode X in the address period of the subfield. For example, as in the case of FIG. 12, the first switch S1 may be turned on and the second switch S2 may be turned off.

In this case, the data voltage Vd supplied by the data voltage source may be supplied to the address electrode X.

Thereafter, the first switch S1 may be turned off and the second switch S2 may be turned on. Then, the address electrode X may be grounded so that the voltage of the address electrode X becomes the voltage of the ground level GND.

In this way, it is possible to supply the data signal Dt to the address electrode X.

As such, in order to supply the data signal Dt to the address electrode X, the first switch S1 and / or the second switch S2 should perform a switching operation. In the case of the first switch S1, since the data voltage Vd must be supplied to the address electrode X, the driving current generated by the switching operation, that is, the magnitude of the displacement current may be relatively large. Moreover, as the number of switching increases, the magnitude of the displacement current generated by the switching operation may also increase.

For example, as in the case of FIG. 13A, a plurality of discharge cells corresponding to the predetermined address electrode X may be On-Off-On-Off-On-Off-On-Off-On-Off. In the case of the same type, the data IC 1000 must repeatedly perform the turn-on and turn-off operations to supply the data signal Dt to the discharge cells that are turned on. In the case of FIG. 13A, the first switch S1 of the data IC 1000 should alternately perform five turn-on operations and five turn-off operations.

In this case, the magnitude of the driving current (displacement current) flowing through the first switch S1 of the data IC 1000 may be relatively large.

On the other hand, as in the case of Figure 13 (B), a plurality of discharge cells corresponding to the predetermined address electrode (X), such as On-On-On-On-On-Off-Off-Off-Off-Off In the case of having a type, the data IC 1000 only needs to perform one turn-on and one turn-off operation to supply the data signal Dt to the discharge cells that are turned on. That is, in order to supply the data signal Dt to five discharge cells continuously turned on, the first switch S1 of the data IC 1000 remains turned on after being turned on once, Since the first switch S1 of the data IC 1000 is turned off once to supply the ground level GND voltage to five discharge cells that are successively turned off, the first switch S1 remains turned off once. Can be.

In this case, the magnitude of the driving current (displacement current) flowing through the first switch S1 of the data IC 1000 may be smaller than that in the case of FIG. 13A.

In the present invention, the driving current flowing through the data IC 1000 can be predicted by analyzing a pattern of the input image data without directly measuring the driving current flowing through the data IC 1000. For example, when the subfield mapped data is analyzed in the subfield mapping step, data patterns shown in FIGS. 13A and 13B can be confirmed.

In this way, it is possible to analyze the pattern of the image data to predict the driving current Ia flowing through the data IC 1000, and to set the harsh condition mode when the predicted driving current Ia is equal to or greater than a preset threshold current.

That is, the number of switching of the switching element that supplies the driving signal to the electrode of the display panel may be proportional to the magnitude of the driving current flowing through the switching element. In other words, the number of changes in data between cells adjacent in the vertical direction, that is, the address electrode X in the longitudinal direction, may be proportional to the magnitude of the driving current flowing through the switching element that supplies the driving signal to the electrodes of the display panel.

In order to set the harsh condition mode by using the change amount of the histogram and the driving current Ia described above, and to lower the brightness of the display panel in the harsh condition mode, the scan electrode Y and / or the sustain electrode in the sustain period of the subfield. It is possible to reduce the number of sustain signals supplied to (Z). This will be described in more detail below.

To describe a method of reducing the number of sustain signals, an average pixel level (APL) will be described first.

14 schematically illustrates the concept of an average picture level (APL).

The average image level APL may be determined as the number of pixels (or cells) turned on among all the pixels.

For example, as in the case of FIG. 14A, the average image level APL may be relatively low when the number of turned-on pixels among all the pixels is relatively small, and thus the overall dark image. In this case, the size of the area OA where the pixels are turned on may be small.

On the other hand, as in the case of FIG. 14B, the average image level APL may be relatively high when the number of turned-on pixels among all the pixels is relatively large and thus the overall bright image. In this case, the size of the area OA where the pixels are turned on may be large.

In addition, the number of sustain signals allocated to one frame may be adjusted according to the average pixel level.

For example, as in the case of FIG. 15, as the average pixel level increases, the number of sustain signals allocated to a frame may decrease. On the other hand, as the average pixel level decreases, the number of sustain signals allocated to the frame may increase.

When the average pixel level is high, the number of turned-on pixels (or cells) is relatively large, and thus reducing the number of sustain signals allocated to the frame can prevent an excessive increase in power consumption.

On the other hand, when the average pixel level is low, the number of pixels (or cells) turned on is relatively small. Therefore, increasing the number of sustain signals allocated to a frame improves image brightness while preventing excessive increase in power consumption. It is possible to let.

As such, if the number of the sustain signals allocated to the frame is adjusted according to the average pixel level of the image data, power consumption may be reduced while preventing a decrease in luminance of the image.

In the severe condition mode, as in the case of FIG. 16, the graph (APL Curve) of the average pixel level can be moved downward. In detail, the graph of the average pixel level in the normal mode (N.M) can be moved downward in the severe mode (E.M). That is, when the image data is the normal mode and the severe condition mode, different average pixel level graphs or tables may be used.

For example, in the normal mode, as in the case of the first table Table 1 shown in FIG. 17, the sustain signal may be allocated according to the average pixel level.

As shown in FIG. 17, when the average power level is 38 levels, the total number of sustain signals allocated to one frame is approximately 512, and when the 39 and 40 levels are, the total number of sustain signals allocated to one frame is approximately. In the case of 510 and 41 levels, the total number of sustain signals allocated to one frame is approximately 508, and in the case of 42 levels, the total number of sustain signals allocated to one frame is approximately 506 and one frame in the case of 898 levels. If the total number of sustain signals assigned to the frame is approximately 284, 899 and 900 levels, the total number of sustain signals allocated to one frame is approximately 283, and if the level is 901, the total number of sustain signals allocated to one frame is Is approximately 282, at 902 levels, the total number of sustain signals allocated to one frame is approximately 281 and at 985 levels, the total number of sustain signals assigned to one frame is If the total number of signals is approximately 256, 986 and 987 levels, the total number of sustain signals allocated to one frame is approximately 255. If the level is 988, the total number of sustain signals allocated to one frame is approximately 254. In the case of 989 levels, the total number of sustain signals allocated to one frame may be approximately 253.

On the other hand, in the harsh condition mode, as in the case of the second table (Table 2) shown in Fig. 18, when the average power level is 38 levels, the total number of sustain signals allocated to one frame is approximately 472, 39 And when the level is 40, the total number of the sustain signals allocated to one frame is approximately 470, and when the level is 41, the total number of the sustain signals allocated to one frame is about 468; If the total number of sustain signals is approximately 466 and 898 levels, the total number of sustain signals allocated to one frame is approximately 254, and if the total number of sustain signals allocated to one frame is approximately At 253 and 901 levels, the total number of sustain signals allocated to one frame is approximately 252, and at 902 level, the total number of sustain signals allocated to one frame is large. In the case of 251 and 985 levels, the total number of sustain signals allocated to one frame is approximately 236. In the case of 986 and 987 levels, the total number of sustain signals allocated to one frame is approximately 235 and 988 levels. When the total number of sustain signals allocated to one frame is approximately 234 and 989 levels, the total number of sustain signals allocated to one frame may be approximately 233.

17 to 18 illustrate the number of sustain signals allocated to one frame and the number of sustain signals allocated to each subfield according to the average power level in the normal mode and the severe condition mode. It is not limited to 17-18.

As described above, in the harsh condition mode, the number of sustain signals allocated to the frame at the same average pixel level may be smaller than that in the normal mode.

For example, suppose that one panel includes 64 cells (8 × 8) in total, as in the case of FIG. 19.

In this case, as shown in FIG. 19A, assuming that a cell group including 2 × 2 cells is turned on alternately, in this case, a total of 32 cells out of 64 cells are turned on. Can be turned on.

In addition, as in the case of (B) of FIG. 19, when adjacent cells are alternately turned on to have different logic states, a total of 32 cells among the 64 cells may be turned on.

That is, when the image data of the pattern of FIGS. 19A and 19B are compared, it can be seen that the average pixel levels are the same in FIGS. 19A and 19B.

In addition, in the case of FIG. 19B, it can be seen that the number of times of switching of the switching element (data IC) is twice as much as in the case of FIG. 19A.

In this case, although the average pixel level is the same in the case of Fig. 19A and 19B, in the case of Fig. 19A, the number of sustain signals allocated to one frame is not shown in Fig. 19B. ) May be more than the number of sustain signals allocated to one frame.

Assuming that image data according to the pattern of FIG. 19A is a first frame F1 and that image data according to the pattern of FIG. 19B is a second frame F2, the first frame F1 ) And the average pixel level APL of the second frame F2 are equal to each other, and the number of changes of data between discharge cells adjacent in the vertical direction (the longitudinal direction of the address electrode X) in the first frame F1 is In the second frame F2, the number of changes of data may be greater than that between discharge cells adjacent in the vertical direction. In this case, the total number of sustain signals allocated to the first frame F1 may be less than the total number of sustain signals allocated to the second frame F2.

Here, the image data according to the second frame F2 may be image data supplied in the harsh condition mode, and the image data according to the first frame F1 may be image data supplied in the normal mode.

As such, it is possible to reduce power consumption by reducing the number of sustain signals allocated to a frame in the harsh condition mode.

For example, as in the case of FIG. 20, as the pattern of the image data increases (the number of switching times increases), the power factor of the display device may also increase.

In this process, when entering the harsh condition mode by satisfying the condition capable of entering the harsh condition mode, an increase in power consumption due to an increase in the pattern of the image data (increase in the number of switching) may be insensitive.

For example, when the harsh mode is entered when the power consumption is P1, the increase rate of the power consumption may decrease even if the pattern of the image data increases. If the maximum power consumed when maintaining the number of sustain signals allocated to a frame in the severe condition mode is maintained as Pmax, the present invention reduces the number of sustain signals allocated to the frame in the severe condition mode to reduce the maximum power consumption. The power may be Pmax-ΔIa.

As such, reducing the maximum power consumption may reduce the maximum power supply of the power supply unit (PSU) that supplies power to the display device.

For example, in a severe condition mode, when the number of sustain signals allocated to a frame is maintained without reducing the power supply, the power supply unit PSU uses the maximum power consumption Pmax of the display device for the maximum margin of the drive margin. Can be designed to be larger than For example, in the case of maintaining the number of sustain signals allocated to a frame in the severe condition mode without reducing the number, the maximum supply power of the power supply device PSU may be Pmax + Pm.

On the other hand, when the number of sustain signals allocated to a frame is reduced in the severe condition mode, the maximum supply power of the power supply device PSU may be Pmax−ΔIa + Pm. Accordingly, since the power supply device PSU can be designed in a direction of lowering the maximum supply power, it is possible to reduce the manufacturing cost.

21A and 21B show an example of an image according to the harsh condition mode.

While displaying the image according to the severe condition mode, the power consumption is compared with the case of reducing the number of sustain signals allocated to the frame and maintaining the number according to the present invention as in the case of FIG. 22.

Assume that the case of FIG. 21A is B type image data, and the case of FIG. 21B is A type image data.

FIG. 22A is data for a 50-inch model, and FIG. 22B is data for a 60-inch model.

Referring to (A) and (B) of FIG. 22, in both 50-inch and 60-inch models, power consumption is relatively lower than in the case of reducing the number of sustain signals allocated to the frame in the harsh condition mode. You can see that.

On the other hand, when the pattern of the image data increases in the harsh condition mode (when the number of switching of the switching elements increases), it is possible to further reduce the number of sustain signals allocated to the frame.

For example, suppose that one panel includes a total of 256 cells (16 × 16) as in the case of FIG. 23.

In this case, assuming that a cell group including 8x8 cells is turned on alternately as in the case of FIG. 23A in the first first frame F1, in this case, a total of 256 cells is turned on. 128 cells may be turned on. In this case, the number of turn-on of the switching device may be about two times. In this case, as in the case of FIG. 24, the average pixel level may correspond to a graph of the average pixel level APL of ①.

In addition, assuming that a cell group including 4x4 cells is turned on alternately as in the case of FIG. 23B in a predetermined second frame F2, in this case, a total of 128 of 256 cells Cells may be turned on, and the number of turn-on times of the switching elements may be approximately eight times. In this case, as in the case of FIG. 24, the average pixel level may correspond to a graph of the average pixel level APL of ②.

In addition, assuming that a cell group including 2x2 cells is turned on alternately as in the case of FIG. 23C in a predetermined third frame F3, in this case, a total of 128 of 256 cells Cells may be turned on, and the number of turn-on times of the switching elements may be approximately 32 times. In this case, as in the case of FIG. 24, the average pixel level may correspond to a graph of the average pixel level APL of ③.

In addition, assuming that each cell is turned on alternately as in the case of FIG. 23D in the predetermined fourth frame F4, in this case, a total of 128 cells of 256 cells are turned on. In addition, the number of turn-on of the switching device may be approximately 128 times. In this case, the average pixel level may correspond to a graph of the average pixel level APL of ④ as in the case of FIG. 24.

23 and 24, the average pixel level of the first, second, third, and fourth frames F1 to F4 is the same, and the number of switching of the switching elements (the amount of patterns in the second frame F2). The sustain allocated to the second frame F2 when the driving current Ia is larger than the number of switching of the switching element (the amount of patterns and the size of the driving current Ia) in the first frame F1. The number of signals may be smaller than the number of sustain signals allocated to the first frame F1. In this way, the number of sustain signals allocated to the third frame F3 is smaller than the number of sustain signals allocated to the second frame F2, and the number of sustain signals allocated to the fourth frame F4 is 3rd. It may be less than the number of sustain signals allocated to the frame (F3).

Assuming that the second, third, and fourth frames F2, F3, and F4 corresponding to FIGS. 23B, 23C, and 3D are image data corresponding to the severe condition mode, the system enters the severe condition mode. Even in the state, when the amount of the pattern of the image data increases (the switching frequency of the switching element increases, the size of the driving current Ia increases), it is possible to further reduce the number of sustain signals allocated to the frame.

In this case, as in the case of Fig. 25, even in the harsh condition mode, even if the amount of the pattern is increased, the power consumption can be maintained without increasing.

On the other hand, when calculating the amount of change in the histogram of the image data, it is possible to set the weight differently according to the gradation interval.

In detail, the weight of the first gradation used in the harsh condition mode is set to be lower than the weight of the second gradation used in the general mode so as to enter the harsh condition mode even if the variation of the first gradation is large. It is possible to set so that. The contents of FIG. 26 below can be inferred from the contents of FIG. 8.

For example, as shown in FIG. 26, when the maximum grayscale of the video data is 1024 grayscales, a weight of G1 is assigned to the first interval H1 corresponding to 0 to 128 grayscales, and from 897 to 1024 grayscales. The weight of G3 is assigned to the corresponding eighth section H8, and the weight of G2 is assigned to the fourth section H4 corresponding to 385 to 512 gradations and the fifth section H5 corresponding to 640 to 640 gradations. Can be assigned.

Here, G2 may be larger than G1 and G3.

In this case, the amount of change in the histogram of the first frame F1 and the second frame F2 is (AR1 + AR2) × G1 + [(AR4 + AR4) + (AR5 + AR6)] × G1 + (AR7 + AR8) × G3 It may correspond to.

Here, when G2 is larger than G1 and G3, it may mean that the amount of change in the histogram in the first frame F1 and the second frame F2 is likely to be determined by (AR4 + AR4) + (AR5 + AR6). Can be. That is, when the histogram of the first frame F1 and the second frame F2 is large in the fourth and fifth sections H4 and H5 having a relatively large weight, the first frame F1 and / or the second In the first and eighth sections H1 and H8 where the weight of the frame F2 is relatively high, the possibility of leaving the severe condition mode may be relatively high, while the first frame F1 and the second frame F2 Even if the difference in the histogram is large, the probability that the first frame F1 and / or the second frame F2 leave the harsh condition mode may be relatively low.

For example, as in the case of FIG. 27, in the seventh section H7 in the second section H2, the first frame F1 and the second frame F2 are the same, and in the first section H1, the first frame F1 is the same. The frequency of use N3 of the 0 to 128 gradations in the image data according to the two frames F2 is higher than the frequency of use N1 of the 0 to 128 gradations in the image data according to the first frame F1 and the eighth period ( H8) when the frequency of use (N3) of 897 to 1024 gradations in the image data according to the first frame F1 is higher than the frequency of use (N1) of 897 to 1024 gradations in the image data according to the second frame F2 Let's assume.

In this case, the difference between the histograms of the first frame F1 and the second frame F2 may correspond to (AR1 × G1) + (AR2 × G3).

On the other hand, as in the case of Figure 28, in the first section (H1) in the third section (H3) and the sixth section (H6) in the eighth section (H8) in the first frame (F1) and the second frame (F2) ) Are the same, and the frequency of use (N3) of 385 to 512 gradations in the image data according to the first frame F1 in the fourth section H1 is 385 to 512 gradations in the image data according to the second frame F2. It is higher than the use frequency N1, and the use frequency N3 of 513 to 640 gradations in the image data according to the second frame F1 in the fifth section H5 is 513 in the image data according to the second frame F2. Let's assume that the case is higher than the frequency of use (N1) of ~ 640 gradations.

In this case, the difference between the histograms of the first frame F1 and the second frame F2 may correspond to (AR3 + AR4) × G2.

27 and 28, the widths of the first section H1, the fourth section H4, the fifth section H5, and the eighth section H8 are equal to each other, and the first frame F1 is the same as the first frame F1. AR1, AR2, AR3, and AR4 may be identical to each other because the difference (N3-N1) of gray level use frequencies of the second frame F2 is the same.

As a result, in the case of FIG. 27, the difference between the histograms of the first frame F1 and the second frame F2 may correspond to (AR1 × G1) + (AR1 × G3) = (AR1 × (G1 + G3)). In FIG. 28, the difference between the histograms of the first frame F1 and the second frame F2 may correspond to (AR1) × 2G2.

Here, since G2 is larger than G1 and G3, (AR1) × 2G2 is larger than (AR1 × (G1 + G3)).

As a result, the change amount of the histogram in the case of FIG. 28 may mean greater than the change amount of the histogram in the case of FIG. 27.

Here, in the case of setting the reference value to (AR1 × (G2 + G1) larger than (AR1 × (G1 + G3)) and smaller than (AR1) × 2G2), the harsh condition mode can be set in the case of FIG. In FIG. 28, the normal mode may be set.

The severe condition mode is likely to be an image having a pattern as shown in FIGS. 21A and 21B, and such an image often has a pattern in which an image of the highest luminance and the lowest luminance is mixed. Accordingly, as described above, setting the weight differently according to the gradation region may be more effective in setting the harsh condition mode.

29 to 39 are diagrams for explaining the case where the present invention is applied to a liquid crystal display device. Hereinafter, the description of the parts described in detail above will be omitted.

Referring to FIG. 29, a display device according to the present invention includes a back light unit 200 including a display panel 100, an optical layer 310, and a light source unit 320, and a back cover. , 330).

The display panel 100 displaying an image may include a front substrate and a rear substrate disposed opposite to each other as a liquid crystal display panel (LCD).

The optical layer 310 may be disposed between the display panel 100 and the rear cover 330.

In addition, the light source unit 320 of the backlight unit 200 may be disposed behind the optical layer 310.

The rear cover 330 may be disposed behind the backlight unit 200.

The rear cover 330 may protect the backlight unit 200 and the display panel 100 from the impact and pressure applied from the outside.

Here, the optical layer 310 may be in close contact with the display panel 100. Alternatively, the optical layer 310 may be spaced apart from the display panel 100 by a predetermined distance.

Alternatively, the light source unit 320 may be in close contact with the optical layer 310 in the backlight unit 200. In this case, the thickness of the display device according to the present invention can be reduced.

As shown in FIG. 30, the display apparatus according to the exemplary embodiment of the present invention may be configured by closely placing the backlight unit 200 on the display panel 100. For example, the backlight unit 200 may be attached to and fixed to the lower side of the display panel 100, more specifically, the lower polarizer 404, and for this purpose, between the lower polarizer 404 and the backlight unit 200. An adhesive layer (not shown) may be formed on the substrate.

By forming the backlight unit 200 in close contact with the display panel 100 as described above, the overall thickness of the display device may be reduced to improve appearance, and the display device may be removed by removing a structure for fixing the backlight unit 200. Can simplify the structure and manufacturing process. In addition, by reducing the space between the backlight unit 200 and the display panel 100, it is possible to prevent the malfunction of the display device due to the insertion of foreign matters into the space or the degradation of the image quality of the display image.

According to an exemplary embodiment of the present invention, the backlight unit 200 may be configured in a form of a plurality of functional layers stacked, and at least one of the plurality of functional layers may include a plurality of light sources (not shown). Can be.

In addition, as described above, in order for the backlight unit 200 to be closely fixed to the lower surface of the display panel 100, the plurality of layers constituting the backlight unit 200, more specifically, the backlight unit 200 may be provided. It is preferable that it is comprised from the material which has each ductility.

In addition, the display panel 100 may include a front substrate 401 and a rear substrate 402 bonded to each other with a liquid crystal layer (not shown) therebetween.

In addition, an upper polarizing plate 403 for polarizing light passing through the display panel 100 is disposed on the front surface of the front substrate 401, and a rear surface of the rear substrate 402 is disposed on the rear surface of the rear substrate 402. The lower polarizer 404 may be disposed to polarize the light passing through the optical layer 310.

A color filter (not shown) for implementing R, G, and B colors may be disposed on the front substrate 401.

The color filter includes a plurality of pixels composed of red (R), green (G), and blue (B) sub-pixels, and a color of red, green, or blue when light is applied. Can generate an image corresponding to

The pixels may be composed of red, green, and blue subpixels, but the red, green, blue, and white (W) subpixels constitute one pixel, and the present invention is not limited thereto.

A predetermined transistor, for example, a thin film transistor (TFT), may be formed in the rear substrate 402 to turn on / off liquid crystals for each pixel. Accordingly, the front substrate 401 may be referred to as a color filter substrate, and the rear substrate 402 may be referred to as a thin film transistor (TFT) substrate.

The liquid crystal layer is composed of a plurality of liquid crystal molecules, the liquid crystal molecules may change the arrangement by the drive signal supplied by the transistor. Accordingly, the light provided from the backlight unit 200 may be incident on the color filter in response to the change in the molecular arrangement of the liquid crystal layer.

Then, at least R, G, and B light are implemented by the color filter, so that a predetermined image may be displayed on the display panel 100.

Referring to FIG. 31, each of the pixels of the display panel 100 may include a TFT in which the data line 500 and the gate line 510 cross each other and are connected to an intersection thereof.

The TFT supplies the data voltage supplied through the data line 500 to the pixel electrode 520 of the liquid crystal cell Clc in response to the gate pulse from the gate line 510. The liquid crystal cell Clc is rotated by an electric field generated in accordance with a voltage difference between the voltage of the pixel electrode 520 and the common voltage Vcom applied to the common electrode 530 to control the light flux passing through the polarizer. The storage capacitor Cst is connected to the pixel electrode of the liquid crystal cell Clc to hold the voltage of the liquid crystal cell Clc.

The structure and configuration of the display panel 100 are merely examples, and modifications, additions, and deletions of the embodiments are possible within the scope of the present invention.

32 is a cross-sectional view of the backlight unit.

Referring to FIG. 32, the backlight unit 200 may include a substrate 610, a light source 620, a resin layer 630, and a reflective layer 640.

The plurality of light sources 620 may be formed on the substrate 610, and the resin layer 630 may be formed on the substrate 610 to surround the plurality of light sources 620.

Although not shown, an electrode pattern (not shown) for connecting the connector (not shown) and the light source 620 may be formed on the substrate 610. For example, a carbon nanotube electrode pattern (not shown) may be formed on the upper surface of the substrate 610 to connect the light source 620 and the connector. The connector may be electrically connected to a power supply unit (not shown) that supplies power to the light source 620.

The substrate 610 may be a film substrate.

The light source 620 may be one of a light emitting diode (LED) chip or a light emitting diode package having at least one light emitting diode chip. In this embodiment, a light emitting diode package is provided as the light source 620 as an example.

The light source 620 may be a colored LED or a white LED emitting at least one of colors such as red, blue, green, and the like. Also, the colored LED may include at least one of a red LED, a blue LED, and a green LED, and the arrangement and emission light of such a light emitting diode may be changed within the technical scope of the embodiment.

On the other hand, the resin layer 630 disposed above the substrate 610 transmits and diffuses the light emitted from the light source 620, so that the light emitted from the light source 620 is uniformly distributed to the display panel 100. Can be provided.

A reflective layer 640 may be formed between the substrate 610 and the resin layer 630, more specifically, on an upper surface of the substrate 610 to reflect light emitted from the light source 620.

The reflective layer 640 may reflect the light totally reflected from the boundary of the resin layer 630 so that the light emitted from the light source 620 may be more widely diffused.

The reflective layer 640 may include a white pigment such as titanium oxide dispersed in a sheet of a synthetic resin material, a metal deposition film laminated on a surface thereof, or a bubble dispersed to scatter light in a synthetic resin sheet. In order to increase the reflectance, silver (Ag) may be coated on the surface. Alternatively, the reflective layer 640 may be formed by coating the upper surface of the substrate 610.

The resin layer 630 may be composed of various resins having light transmittance. For example, the resin layer 630 may include any one material or at least two materials selected from the group consisting of polyethylene terephthalate, polycarbonate, polypropylene, polyethylene, polystyrene, polyepoxy, silicone, acrylic, and the like. Do.

The resin layer 630 may include a polymer resin having adhesiveness so as to be in close contact with the light source 620 and the reflective layer 640. For example, the resin layer 630 is unsaturated polyester, methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, normal butyl methacrylate, normal butyl methyl methacrylate, acrylic acid, methacrylic acid, hydride Hydroxy ethyl methacrylate, hydroxy propyl methacrylate, hydroxy ethyl acrylate, acrylamide, metyrol acrylamide, glycidyl methacrylate, ethyl acrylate, isobutyl acrylate, normal butyl acrylate, 2- It may comprise an acrylic, urethane, epoxy, melamine, such as ethyl hexyl acrylate polymer or copolymer or terpolymer.

The resin layer 630 may be formed by applying a resin on a liquid or gel to the upper surface of the substrate 610 on which the plurality of light sources 620 and the reflective layer 640 are formed, and then curing the resin. It may be formed separately and bonded to the upper surface of the substrate 610.

Although the backlight unit 200 is described as including the light source unit 320, the optical layer 310, and a frame (not shown), the backlight unit 200 may also include a light guide plate (not shown). have. Alternatively, the expression backlight unit 200 may be used to mean the light source 620. As such, the configuration of the backlight unit 200 may be variously changed.

In addition, a bottom cover (not shown) on which the backlight unit 200 is seated may be provided below the backlight unit 200.

According to an exemplary embodiment of the present invention, the display panel 100 may be divided into a plurality of areas, and the display panel 100 may be divided from areas of the backlight unit 200 corresponding to gray peak values or color coordinate signals of each of the divided areas. The brightness of the emitted light, that is, the brightness of the corresponding light source, may be adjusted to adjust the brightness of the display panel 100.

To this end, the backlight unit 200 may be divided into a plurality of divided driving regions corresponding to each of the divided regions of the display panel 100.

Various types of light sources 620 may be applied to the present invention. For example, the light source may be one of a light emitting diode (LED) chip or a light emitting diode package having at least one light emitting diode chip. In this case, the light source may be a colored LED or a white LED that emits at least one color among colors such as red, blue, green, and the like.

In addition, although only the case where the backlight unit 200 is an example of a direct type is illustrated here, an edge type backlight unit may be applied in the present invention.

33 is a sectional view showing another configuration of the backlight unit. Hereinafter, the description of the parts described in detail with reference to FIG. 33 will be omitted.

Referring to FIG. 33, a plurality of light sources 620 may be mounted on the substrate 610, and a resin layer 630 may be disposed on the substrate 610. The reflective layer 640 may be formed between the substrate 610 and the resin layer 630.

In addition, the resin layer 630 may include a plurality of scattering particles 631, and the scattering particles 631 may scatter or refract incident light so that light emitted from the light source 620 may be spread more widely. can do.

The scattering particles 631 may be formed of a material having a refractive index different from that of the material of the resin layer 630, more specifically, a silicon-based material of the resin layer 630 in order to scatter or refract light emitted from the light source 620. Or it may be made of a material having a higher refractive index than the acrylic resin.

For example, the scattering particles 631 may be composed of titanium dioxide (TiO 2), silicon dioxide (SiO 2), or the like, and may be formed by combining the above materials.

On the other hand, the scattering particles 631 may be made of a material having a lower refractive index than the material constituting the resin layer 630, for example, may be formed by forming a bubble (bubble) in the resin layer 630. .

In addition, the material constituting the scattering particles 631 is not limited to the above materials, and may be formed using various polymer materials or inorganic particles.

According to an exemplary embodiment of the present invention, the resin layer 630 is a substrate 610 in which a plurality of light sources 620 and a reflective layer 640 are formed after mixing the scattering particles 631 with a resin in a liquid or gel form. It may be formed by applying to the upper surface of the) and then curing.

Referring to FIG. 33, an optical layer 310 may be disposed on the resin layer 630, for example, the optical layer 310 may include a prism sheet 651 and a diffusion sheet 652. . In this case, the plurality of sheets included in the optical layer 310 may be provided in a state of being adhered or adhered to each other without being spaced apart from each other, thereby minimizing the thickness of the optical layer 310 or the backlight unit 200.

On the other hand, the lower surface of the optical layer 310 is in close contact with the resin layer 630, the upper surface of the optical layer 310 is in close contact with the lower surface of the display panel 100, more specifically, the lower polarizing plate 404. Can be.

The diffusion sheet 652 diffuses the incident light to prevent the light emitted from the resin layer 630 from being partially concentrated, thereby making the brightness of the light uniform. In addition, the prism sheet 651 may collect light from the diffusion sheet 652 to allow light to enter the display panel 100 vertically.

According to another embodiment of the present invention, the optical layer 310 as described above, for example, at least one of the prism sheet 651 and the diffusion sheet 652 may be removed, or the prism sheet 651 and In addition to the diffusion sheet 652 may be configured to further include a variety of functional layers.

Referring to FIG. 34, a plurality of light sources 620 may be disposed on the substrate 610 in a predetermined type.

Although not shown, a transport line for supplying power to the plurality of light sources 620 disposed on the substrate 610 may be formed on the substrate 610.

In addition, a power terminal Vcc and a ground terminal GND for supplying power to the light source 620 may be formed on the substrate 610.

As shown in FIG. 34, a case in which the plurality of light sources 620 are arranged side by side on the substrate 610 may be referred to as a direct type. In such a direct method, the LED package constituting the light source 620 may be divided into a top view method and a side view method according to a direction in which the light emitting surface is directed.

35 is a diagram illustrating an example of an equivalent circuit of the display apparatus 700 according to an exemplary embodiment of the present invention.

Referring to FIG. 35, a display apparatus 700 according to an exemplary embodiment of the present invention includes a display panel 100, a timing controller 710, a data driver circuit 720, a gate driver circuit 730, and the like.

As described above, the display panel 100 may include a liquid crystal layer formed between the front substrate and the rear substrate. The display panel 100 may include pixel arrays arranged in a matrix by a cross structure of the data lines 500 and the gate lines 510.

The TFT array substrate of the display panel 100 includes data lines 500, gate lines 510 crossing the data lines 500, and intersections of the data lines 500 and the gate lines 510. The formed TFT, the pixel electrode of the liquid crystal cell Clc connected to the TFT, the storage capacitor connected to the pixel electrode, and the like are formed.

The data lines 500 are formed along the column direction (Y-axis direction), and the gate lines 510 are formed along the line direction (X-axis direction) perpendicular to the column direction. Black matrices, color filters, and the like are formed on the color filter array substrate of the display panel 100.

The liquid crystal cells Clc charge the video data voltage supplied through the TFT and are driven by the electric field between the pixel electrode and the common electrode. The common voltage Vcom is supplied to the common electrode. The common electrode may be formed on the TFT array substrate and / or the color filter array substrate. A polarizing plate is attached to each of the TFT array substrate and the color filter array substrate of the display panel 100. An alignment film for setting a pre-tilt angle of liquid crystal molecules is formed on a surface of the TFT array substrate and the color filter array substrate, which face the liquid crystal layer, respectively.

The display panel 100 is implemented in a vertical electric field driving method such as twisted nematic (TN) mode and vertical alignment (VA) mode, or a horizontal electric field driving method such as IPS (In Plane Switching) mode and FFS (Fringe Field Switching) mode. It can be implemented as. The display device of the present invention may be implemented in any form, such as a transmissive display device, a transflective display device, a reflective display device. In the transmissive display device and the transflective display device, the backlight unit 200 is required.

The timing controller 710 may convert 8-bit digital video data RGB of an input image input from an external host system 800 into 6-bit digital video data and supply it to the data driving circuit 720.

The timing controller 710 receives timing signals such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a data enable signal DE, and a dot clock CLK from the host system 800. Timing control signals for controlling the operation timing of the driving circuit 720 and the gate driving circuit 730 are generated. The timing control signals include a gate timing control signal for controlling the operation time of the gate drive circuit 730, a data timing control signal for controlling the operation timing of the data drive circuit 720 and the polarity of the data voltage.

The host system 800 may include a main board such as a broadcast signal receiver, a navigation terminal, a portable information terminal, and the like. The main board may transmit timing signals Vsync, Hsync, DE, and DCLK together with the digital video data RGB of the input image to the timing controller 710 through a scaler of the graphic controller.

The gate timing control signal includes a gate start pulse (GSP), a gate shift clock (GSC), a gate output enable signal (GOE), and the like. The gate start pulse GSP controls the operation start timing of the gate drive circuit 730. The gate shift clock GSC is a clock signal for shifting the gate start pulse GSP. The gate output enable signal GOE controls the output timing of the gate drive circuit 730.

The data timing control signal includes a source start pulse SSP, a source sampling clock SSC, a polarity control signal POL, a source output enable signal SOE, and the like. The source start pulse SSP controls the data sampling start timing of the data driving circuit 720. The source sampling clock SSC is a clock signal for controlling the sampling timing of the digital video data in the data driving circuit 720. The source output enable signal SOE controls the output timing and charge sharing timing of the data driving circuit 720. The polarity control signal POL indicates the polarity inversion timing of the data voltage outputted from the data driving circuit 720. [

The timing controller 710 may adjust a driving signal supplied to the backlight unit 200 in order to adjust the brightness of the display panel 100 in the video mode. For example, the timing controller 710 may adjust the amount of light generated by the light source 620 by adjusting the driving signal supplied to the power terminal Vcc formed on the substrate 210 of FIG. 34 in the video mode. In this way, the timing controller 710 adjusts the amount of light generated by the backlight unit 200 in the harsh condition mode, and as a result, it is possible to adjust the brightness of the display panel 100. This operation is made clearer through the following description.

The data driving circuit 720 includes a plurality of source drive ICs. The data driving circuit 720 latches the 6-bit digital video data (RGB) input from the timing controller 710 in response to the data timing control signal. The data driving circuit 720 converts the digital video data RGB to an analog positive / negative gamma compensation voltage in response to the polarity control signal POL to generate a positive / negative analog data voltage. The positive polarity / negative polarity data voltages output from the data driving circuit 720 are supplied to the data lines 500.

The gate driving circuit 730 sequentially supplies gate pulses synchronized with the data voltage to the gate lines 510 in response to the gate timing control signals.

The timing controller 710, the data driving circuit 720 and the gate driving circuit 730 described above may collectively be referred to as a driver. Hereinafter, those that supply a predetermined signal for the operation of the display apparatus are collectively called a driver.

On the other hand, the liquid crystal display device may also include a switching element for supplying a drive signal to the electrodes (scan line, data line) of the liquid crystal display panel 100.

For example, as in the case of FIG. 36, the data driving circuit 720 may include a plurality of data ICs 3600 for supplying data voltages to the data lines D1 to Dx.

The data IC 3600 may include a first switch S1 and a second switch S2 disposed between the data voltage source supplying the data voltage Vd and the ground GND.

In addition, the data line D1 to Dx may be connected to the node n1 between the first switch S1 and the second switch S2.

In consideration of the driving current Ia flowing through the data IC 3600, for example, the driving current flowing through the first switch S1, it is possible to set to the harsh condition mode. This can be inferred from the foregoing 11 and the corresponding contents.

In addition, in consideration of the histogram of the image data as well as the current flowing through the data IC 3600, it is possible to set to the harsh condition mode. Since it has been described in detail above, further description thereof will be omitted.

Meanwhile, in the harsh condition mode, the amount of light generated by the backlight unit may be reduced in order to reduce the brightness of the display panel.

For example, as in the case of FIG. 37, the luminance Cd1 of the light generated in the backlight unit in the normal mode may be higher than the luminance Cd2 of the light generated in the backlight unit in the harsh condition mode.

Even in this case, it is possible to reduce the power consumption and to lower the manufacturing cost of the power supply unit (PSU).

It is possible to adjust the driving signal supplied to the backlight unit in order to reduce the amount of light generated in the backlight unit in the harsh condition mode. To illustrate this, it is assumed that the backlight unit includes the substrate 210 and the light sources 220 having the structure described with reference to FIG. 35.

For example, as in the case of FIG. 38A, in the frame according to the general mode, the light sources 220 are supplied by supplying a driving signal having the first voltage V1 to the power terminal Vcc of the substrate 210. It can be turned on. In addition, in the frame according to the harsh condition mode, the light source 220 may be turned on by supplying a driving signal having a second voltage V2 lower than the first voltage V1 to the power terminal Vcc of the substrate 210. Can be. That is, the backlight unit 200 generates power by making the voltage V2 of the driving signal supplied to the light source 220 in the harsh condition mode smaller than the voltage V1 of the driving signal supplied to the light source 220 in the normal mode. It is possible to reduce the amount of light.

Alternatively, as shown in (B) of FIG. 38, in the frame according to the general mode, 1 to 8 driving pulses (DP) are supplied to the light source 220, and the light source 220 is turned on, and the severe condition mode is performed. In the frame according to ① ~ ⑤ driving pulse (DP) is supplied to the light source 220 may be turned on the light source 220.

As such, in the harsh condition mode, the amount of light generated by the backlight unit 200 may be reduced by reducing the number of driving pulses DP supplied to the light source 220.

Alternatively, in the frame according to the normal mode as shown in FIG. 38C, the light source 220 is turned on by supplying the first driving pulse DP1 having the first pulse width W1 to the light source 220. In the frame according to the severe condition mode, the light source 220 is turned on by supplying a second driving pulse DP2 having a second pulse width W2 smaller than the first pulse width W1 to the light source 220. You can.

As described above, in the harsh condition mode, the amount of light generated by the backlight unit 200 may be reduced by reducing the pulse width of the driving pulse DP supplied to the light source 220.

Alternatively, although not shown, in the harsh condition mode, it is possible to reduce the amount of light generated by the backlight unit 200 by reducing the amount of current supplied to the light source 220.

On the other hand, when the amount of the pattern increases in the harsh condition mode (the size of the driving current Ia increases and the number of switching of the switching elements increases), the luminance of the display panel is further lowered, that is, generated in the backlight unit. It is possible to reduce the amount of light.

For example, as in the case of FIG. 39, when entering the harsh condition mode in the normal mode, the brightness of light generated in the backlight unit may decrease, and when the amount of the pattern increases, the amount of light generated in the backlight unit may be It is possible to further reduce. For example, assuming that the luminance of light generated in the backlight unit in the normal mode is the first luminance Cd1, the luminance of light generated in the backlight unit in the harsh condition mode is lower than the first luminance Cd1. When the amount of the pattern is increased, the luminance of light generated by the backlight unit may decrease from the second luminance Cd2 to the third luminance Cd3.

40 is a view for explaining the configuration of a broadcast signal receiver to which the display device according to the present invention is applied. Hereinafter, the description of the parts described in detail above will be omitted. The broadcast signal receiver described herein as an example of a terminal is, for example, an intelligent broadcast signal receiver in which a computer support function is added to the broadcast reception function. The broadcast signal receiver is faithful to the broadcast reception function and has an Internet function added thereto. It can be equipped with a more convenient interface such as a space remote control. In addition, by being connected to the Internet and a computer with the support of a wired or wireless Internet function, it is possible to perform functions such as e-mail, web browsing, banking or gaming. A standardized general-purpose OS can be used for these various functions.

Accordingly, the broadcast signal receiver described in the present invention can perform various user-friendly functions because various applications can be freely added or deleted on a general-purpose OS kernel, for example. More specifically, the broadcast signal receiver may be, for example, a network TV, an HBBTV, a smart TV, or the like, and may be applied to a smartphone in some cases.

Referring to FIG. 40, the broadcast signal receiver according to the present invention may include a driver 110, a display unit 100, and an audio output unit 185Q. Here, the driving unit 110 may correspond to at least one of reference numeral 110 of FIG. 1 or 710, 720, and 730 of FIG. 35. In addition, the display unit 100 may correspond to the above-described plasma display panel or liquid crystal display panel.

The driver 110 may include a broadcast receiver 105Q, an external device interface 135Q, a storage 140Q, a user input interface 150Q, a controller 170Q, a power supply 190Q, and a photographing unit (not shown). ) May be included. The broadcast receiving unit 105Q may include a tuner 110Q, a demodulating unit 120Q, and a network interface unit 130Q.

Of course, the tuner 110Q and the demodulator 120Q may be provided, but the network interface 130Q may not be included. Alternatively, the tuner 110Q and the demodulator 120Q may be included, It is also possible to design it not to include the demodulator 120Q.

The tuner 110Q selects an RF broadcast signal corresponding to a channel selected by the user or all previously stored RF (Radio Frequency) broadcast signals. Also, the selected RF broadcast signal is converted into an intermediate frequency signal, a baseband image, or a voice signal.

The demodulator 120Q receives the digital IF signal DIF converted by the tuner 110Q and performs a demodulation operation.

For example, when the digital IF signal output from the tuner 110Q is of the ATSC scheme, the demodulator 120Q performs 8-VSB (8-Vestigal Side Band) demodulation, for example. Also, the demodulator 120Q may perform channel decoding. The demodulator 120Q includes a trellis decoder, a de-interleaver, and a Reed Solomon decoder for performing trellis decoding, deinterleaving, and lead decoding. Solomon decoding can be performed.

The demodulator 120Q may demodulate and decode the channel, and then output the stream signal TS. At this time, the stream signal may be a signal in which a video signal, a voice signal, or a data signal is multiplexed.

The stream signal output from the demodulation unit 120Q may be input to the control unit 170Q. The control unit 170Q performs demultiplexing, video / audio signal processing, and the like, and then outputs the video to the display unit 100 and the audio output unit 185Q.

The external device interface unit 135Q may connect the external device to the broadcast signal receiver. To this end, the external device interface unit 135Q may include an A / V input / output unit (not shown) or a wireless communication unit (not shown).

On the other hand, the external device interface unit 135Q can receive the application or application list in the adjacent external device, and can transmit the application or application list to the control unit 170Q or the storage unit 140Q.

The network interface unit 130Q provides an interface for connecting the broadcast signal receiver with a wired / wireless network including an internet network.

The network interface unit 130Q can transmit or receive data to another user or another electronic device via the network to which it is connected or another network linked to the connected network.

In addition, the network interface unit 130Q may receive data and broadcast signals for the multicast service.

In addition, the network interface unit 130Q can be an Ethernet port applicable to a LAN environment.

The storage unit 140Q may store a program for each signal processing and control in the control unit 170Q or may store a signal-processed video, audio, or data signal.

The storage unit 140Q may also function to temporarily store video, audio, or data signals input from the external device interface unit 135Q or the network interface unit 130Q. In addition, the storage unit 140Q can store information on a predetermined broadcast channel through the channel memory function.

40 illustrates an embodiment in which the storage unit 140Q is provided separately from the control unit 170Q, but the scope of the present invention is not limited thereto. The storage unit 140Q may be included in the controller 170Q.

The user input interface unit 150Q transmits a signal input by the user to the controller 170Q or a signal from the controller 170Q to the user.

For example, the user input interface unit 150Q may turn on / off the power from the remote control device 200Q, select a channel, select a channel from the remote control device 200Q according to various communication methods such as an RF (Radio Frequency) communication method, Or a control signal from the control unit 170Q to the remote control device 200Q.

For example, the user input interface unit 150Q can transmit a control signal input from a local key (not shown) such as a power key, a channel key, a volume key, and a set value to the controller 170Q.

For example, the user input interface unit 150Q may transmit a control signal input from a sensing unit (not shown) that senses a user's gesture to the control unit 170Q, or may sense a signal from the control unit 170Q (Not shown). Here, the sensing unit (not shown) may include a touch sensor, an audio sensor, a position sensor, an operation sensor, and the like.

The control unit 170Q demultiplexes the input stream or processes the demultiplexed signals through the tuner 110Q or the demodulation unit 120Q or the external device interface unit 135Q to generate a signal for video or audio output Can be generated and output.

The image signal processed by the controller 170Q is input to the display unit 100 and can be displayed as an image corresponding to the image signal. The video signal processed by the controller 170Q may be input to the external output device through the external device interface unit 135. [

The audio signal processed in the control unit 170Q may be output to the audio output unit 185Q. In addition, the voice signal processed in the controller 170Q may be input to the external output device through the external device interface unit 135Q.

In addition, the controller 170Q may control the broadcast signal receiver by a user command or an internal program input through the user input interface unit 150Q.

For example, the controller 170Q controls the tuner 110Q to input a signal of a selected channel according to a predetermined channel selection command received through the user input interface unit 150Q. Then, video, audio, or data signals of the selected channel are processed. The controller 170Q may output the channel information selected by the user together with the processed video or audio signal through the display unit 100 or the audio output unit 185Q.

As another example, the controller 170Q may, for example, receive an external device image playback command received through the user input interface unit 150Q from an external device, for example, a camera or a camcorder, input through the external device interface unit 135Q. The video signal or the audio signal may be output through the display unit 100 or the audio output unit 185Q.

Meanwhile, the controller 170Q may control the display unit 100 to display an image. For example, a broadcast image input through the tuner 110Q, an external input image input through the external device interface unit 135Q, an image input through a network interface unit, or an image stored in the storage unit 140Q. The display unit 100 may control the display to be displayed.

The display unit 100 may output an image in response to an image signal, a data signal, an OSD signal processed by the controller 170Q, or an image signal, a data signal received from the external device interface unit 135Q.

The audio output unit 185Q receives the signal processed by the control unit 170Q and outputs it as a voice. The voice output unit 185Q may be implemented by various types of speakers.

Meanwhile, in order to detect the gesture of the user, as described above, a sensing unit (not shown) including at least one of a touch sensor, a voice sensor, a position sensor, and a motion sensor may be further provided in the broadcast signal receiver. A signal sensed by a sensing unit (not shown) may be transmitted to the controller 170Q through the user input interface unit 150Q.

On the other hand, a photographing unit (not shown) for photographing a user may be further provided. The image information photographed by the photographing unit (not shown) may be input to the control unit 170Q.

The control unit 170Q may sense the gesture of the user by combining the images captured from the photographing unit (not shown) or the sensed signals from the sensing unit (not shown), respectively.

The power supply unit 190Q supplies the corresponding power throughout the broadcast signal receiver. The power supply unit may correspond to the aforementioned power supply unit PSU.

The remote control device 200Q transmits the user input to the user input interface unit 150Q. To this end, the remote control apparatus 200 can use Bluetooth, RF (radio frequency) communication, infrared (IR) communication, UWB (Ultra Wideband), ZigBee, or the like.

Also, the remote control device 200Q can receive the video, audio, or data signal output from the user input interface unit 150Q and display it on the remote control device 200Q or output voice or vibration.

As described above, it is to be understood that the technical structure of the present invention can be embodied in other specific forms without departing from the spirit and essential characteristics of the present invention.

It should be understood, therefore, that the embodiments described above are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than the foregoing description, And all changes or modifications derived from equivalents thereof should be construed as being included within the scope of the present invention.

Claims (10)

A display panel displaying an image and including an electrode; And
A driver supplying a driving signal for displaying an image to the electrode of the display panel;
Lt; / RTI >
The driving unit
A display device for reducing the brightness of the display panel corresponding to the image data in the harsh condition mode. The method of claim 1,
The harsh condition mode is set when the amount of change in the histogram of the image data is equal to or less than a preset reference time or more, and the current flowing through the switching element for supplying a driving signal to the electrode is equal to or greater than a preset threshold current. Display device. 3. The method of claim 2,
The display panel
A front substrate on which scan electrodes and sustain electrodes are disposed;
A rear substrate having an address electrode intersecting the scan electrode and the sustain electrode; And
A partition wall partitioning a discharge cell between the front substrate and the rear substrate;
/ RTI >
The driving unit
A data IC for supplying a data signal to the address electrode in an address period of a subfield;
The driving unit
And the number of sustain signals supplied to the scan electrode and the sustain electrode in the sustain period after the address period of the subfield in the harsh condition mode. The method of claim 3, wherein
And the data IC corresponds to the switching element. 5. The method of claim 4,
The average pixel level (Average Picture Level, APL) of the first frame (Frame 1) and the second frame (Frame 2) of the image data is the same,
When the number of changes of the data between the discharge cells adjacent in the vertical direction in the first frame is more than the number of changes of the data between the discharge cells adjacent in the vertical direction in the second frame,
And a total number of the sustain signals allocated to the first frame is less than a total number of the sustain signals allocated to the second frame. The method of claim 5, wherein
The image data according to the first frame is image data supplied in the harsh condition mode.
And the image data according to the second frame is image data supplied in a normal mode. 3. The method of claim 2,
Further comprising a backlight unit (Back Light Unit) for emitting light,
The display panel
A front substrate and a rear substrate disposed to face each other; And
A liquid crystal layer disposed between the front substrate and the rear substrate;
/ RTI >
The driving unit
A data IC for supplying a data signal to a data line formed on the display panel;
The driving unit
And a display device to reduce power supplied to the backlight unit in the harsh condition mode. The method of claim 7, wherein
The average pixel level (Average Picture Level, APL) of the first frame (Frame 1) and the second frame (Frame 2) of the image data is the same,
When the number of changes of the data between the cells adjacent in the vertical direction in the first frame is greater than the number of changes of the data between the cells adjacent in the vertical direction in the second frame,
And a luminance of light emitted from the backlight unit in the first frame is smaller than luminance emitted from the backlight unit in the second frame. The method of claim 8,
The image data according to the first frame is image data supplied in the harsh condition mode.
And the image data according to the second frame is image data supplied in a normal mode. 3. The method of claim 2,
And a decrease in luminance of the display panel corresponding to the image data increases as a current flowing through a switching element for supplying a driving signal to the electrode in the harsh condition mode increases.

Images