KR101127857B1 - Apparatus and method for driving of image display device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving apparatus and a driving method of an image display device, which minimizes the flow of motion of a display image so as to increase the display quality of a moving image.

An apparatus for driving an image display apparatus according to the present invention comprises: an image display portion including pixel cells formed for each region defined by a plurality of gate lines and a plurality of data lines; A timing controller for converting data of one frame into two different subframe data or converting the data of one frame into two subframe data identical to the data of one frame; A gate driver for sequentially supplying scan pulses to gate lines for each subframe under the control of the timing controller; And a data driver for converting data of the subframe supplied from the timing controller into an analog video signal and supplying the data to the data lines under the control of the timing controller.

Motion flow, impulse, hold, subframe, black

Description

Driving apparatus and driving method of an image display device {APPARATUS AND METHOD FOR DRIVING OF IMAGE DISPLAY DEVICE}

1 is a characteristic diagram showing driving characteristics of a display device driven in an impulse form.

2 is a characteristic diagram illustrating driving characteristics of a display device driven in a hold form.

3 is a view schematically showing a driving device of an image display device according to an embodiment of the present invention;

4 is a block diagram schematically showing the timing controller shown in FIG.

FIG. 5 is a block diagram schematically illustrating a data converter shown in FIG. 4. FIG.

6A to 6B are diagrams illustrating subframe data generated by the subframe data generator shown in FIG. 5;

<Explanation of Signs of Major Parts of Drawings>

2: image display section 4: data driver

6: gate driver 8: timing controller

22: control signal generator 24: data alignment unit

26: data conversion unit 120: comparison unit

124: sub frame data generation unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display apparatus, and more particularly, to a driving apparatus and a driving method of an image display apparatus, which minimizes the flow of motion of a display image to increase the display quality of a moving image.

Recently, various flat panel display devices that can reduce weight and volume, which are disadvantages of cathode ray tubes, have emerged. Examples of such flat panel display devices include a liquid crystal display, a field emission display, a plasma display panel, and a light emitting display.

Among flat panel displays, liquid crystal displays display moving images using thin film transistors as switching elements. The liquid crystal display device can be miniaturized compared to the cathode ray tube, and is widely used in personal computers and notebook computers, as well as office automation equipment such as photocopiers and portable devices such as mobile phones.

Meanwhile, the cathode ray tube, the plasma display panel, and the field emission display device display data by emitting phosphors for only a very short initial time of one frame period as shown in FIG. 1, and almost all of one frame period is paused. The display device is driven in the form of an impulse that remains.

In the display device driven in the form of an impulse, continuity of adjacent frame images is blocked, so that the display image is excellent in clarity and the blurring phenomenon in which the display image is blurred is prevented.

In contrast, the liquid crystal display and the light emitting display are configured to display data by supplying data to the liquid crystal during the scanning period by the gate high voltage as shown in FIG. It is a display device driven in a hold form. In the display device driven in the hold mode, the image is maintained at one frame period, and thus, a motion blurring phenomenon occurs in which a moving image to be displayed is blurred.

Accordingly, an object of the present invention is to provide a driving apparatus and a driving method of an image display apparatus, which can improve the display quality of a moving image by minimizing the operation flow phenomenon of the display image.

According to an aspect of the present invention, there is provided a driving apparatus of an image display apparatus, including: an image display unit including pixel cells formed in regions defined by a plurality of gate lines and a plurality of data lines; A timing controller for converting data of one frame into two different subframe data or converting the data of one frame into two subframe data identical to the data of one frame; A gate driver for sequentially supplying scan pulses to gate lines for each subframe under the control of the timing controller; And a data driver for converting data of the subframe supplied from the timing controller into an analog video signal and supplying the data to the data lines under the control of the timing controller.

The reference gray scale value may be set within a range of 1/2 to 3/4 of the total gray scale value of the data.

A driving method of an image display apparatus according to an embodiment of the present invention includes an image display apparatus including an image display unit having a liquid crystal cell formed for each region defined by a plurality of gate lines and a plurality of data lines; Converting data of one frame input using reference grayscale values into two different subframe data or two subframe data identical to the data of the one frame; Sequentially supplying scan pulses to gate lines for each subframe; And converting the data of the subframe into an analog video signal and supplying the data lines to be synchronized with the scan pulse.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings and embodiments.

3 is a view schematically illustrating a driving device of a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 3, a driving apparatus of a liquid crystal display according to an exemplary embodiment of the present invention includes a liquid crystal cell formed for each region defined by n gate lines GL1 to GLn and m data lines DL1 to DLm. An image display unit 2; Timing for converting input data Data of one frame into two different subframe data RBG using the reference gray value Ref or converting the same subframe data GBG to the same data of the one frame A controller 8; A gate driver 6 for sequentially supplying scan pulses to the gate lines GL1 to GLn for each subframe under the control of the timing controller 8; And a data driver 4 for converting the data RGB of each subframe supplied from the timing controller 8 into an analog video signal under the control of the timing controller 8 and supplying the analog video signal to the data lines DL1 to DLm. .

The image display unit 2 includes a transistor array substrate and a color filter array substrate bonded to each other, a spacer for maintaining a constant cell gap between the two array substrates, and a liquid crystal filled in a liquid crystal space provided by the spacer.

The image display unit 2 includes a TFT formed in an area defined by n gate lines GL1 to GLn and m data lines DL1 to DLm, and liquid crystal cells connected to the TFT. The TFT supplies an analog video signal from the data lines DL1 to DLm to the liquid crystal cell in response to the scan pulses from the gate lines GL1 to GLn. Since the liquid crystal cell is composed of a common electrode facing each other with a liquid crystal interposed therebetween and a pixel electrode connected to the TFT, the liquid crystal cell may be equivalently represented as a liquid crystal capacitor Clc. The liquid crystal cell includes a storage capacitor Cst for maintaining the analog video signal charged in the liquid crystal capacitor Clc until the next analog video signal is charged.

The timing controller 8 arranges the input data Data input from the outside so as to be suitable for driving the image display unit 2, and arranges the data Data ′ aligned with each other according to the set reference gradation value Ref. The same at least two sub-frame data RGB are converted and supplied to the data driver 4.

In addition, the timing controller 8 uses the main clock MCLK, the data enable signal DE, and the horizontal and vertical synchronization signals Hsync and Vsync, which are input from the outside, to the data control signal DCS and the gate control signal ( GCS) is generated to control the driving timing of each of the data driver 4 and the gate driver 6.

The gate driver 6 sequentially shifts the scan pulse, that is, the gate high pulse, in response to the gate start pulse GSP and the gate shift clock GSC among the gate control signals GCS from the timing controller 8. It includes. The gate driver 6 sequentially turns on the TFT connected to the gate line GL by supplying gate high pulses sequentially to the gate lines GL of the image display unit 2 for each subframe.

The data driver 4 converts the data RGB of each subframe supplied from the timing controller 8 into an analog video signal according to the data control signal DCS supplied from the timing controller 8, and for each subframe. The analog video signal for one horizontal line is supplied to the data lines DL every one horizontal period in which the scan pulse is supplied to the gate line GL. That is, the data driver 4 selects a gamma voltage having a predetermined level according to the gray value of the data RGB, and supplies the selected gamma voltage to the data lines DL1 to DLm. At this time, the data driver 4 inverts the polarity of the analog video signals supplied to the data lines DL in response to the polarity control signal POL supplied from the timing controller 8.

FIG. 4 is a block diagram schematically illustrating the timing controller shown in FIG. 3.

4, the timing controller 8 includes a control signal generator 22 for generating control signals DCS and GCS; A data alignment unit 24 for aligning the input data Data with the driving of the image display unit 2; And a data converter 26 for converting the data Data 'sorted according to the set reference gray value Ref into at least two subframe data RGBs which are different or identical to each other and supply the data data to the data driver 4. .

The control signal generator 22 uses the main clock MCLK, the data enable signal DE, and the horizontal and vertical synchronization signals H and V inputted from the outside to control the gate control signals GCS (GSC, GSP, and GOE). Etc.) and data control signals DCS (SSC, SSP, SOE, POL, etc.).

The data alignment unit 24 aligns the input data Data input from the outside to be suitable for driving the image display unit 2, and supplies the aligned data Data 'to the data conversion unit 26.

As shown in FIG. 5, the data converter 26 generates a comparison signal Cs by comparing the gray value of the sorted data Data ′ from the data sorter 24 with the reference gray value Ref. A comparator 120; According to the comparison signal Cs from the comparator 120, at least two sub-frame data RGB different from each other or at least two subs equal to each other using the sorted data Data 'from the data alignment unit 24. And a sub frame data generation unit 124 for generating frame data RGB and supplying the frame data RGB to the data driver 4.

The comparison unit 120 supplies the comparison signal Cs of the first logic state to the subframe data generation unit 124 when the gray level value of the sorted data Data 'is smaller than the reference gray value Ref. Otherwise, the comparison signal Cs of the second logic state is supplied to the sub frame data generation unit 124. Here, the reference gray scale value Ref is set in a range of 1/2 to 3/4 of the total gray scale value of the sorted data Data '. Hereinafter, it is assumed that the reference gradation value Ref is 3/4 ('191' gradation when 8 bits) of the total gradation value of the sorted data Data '.

When the comparison signal Cs of the first logic state is supplied from the comparator 120, the sub frame data generator 124 increases the gray value of the sorted data Data ′ and is shown in FIGS. 6A to 6C. As described above, at least two different subframe data RGBs are generated. Here, it is assumed that one frame is divided into two subframes SF1 and SF2, and periods of each subframe SF1 and SF2 may be the same or different from each other within one frame.

In detail, as illustrated in FIG. 6A, when the gray value of the input data Data is '63' gray that is lower than the reference gray value Ref, the sub frame data generator 124 may select the '127' gray value. The subframe data RGB having a gray scale value of '127' is generated using the input data Data '. That is, the sub frame data generator 124 generates sub frame data RGB that is equal to the luminance of the input data Data '.

Accordingly, the subframe data generator 124 supplies the subframe data RGB generated during any one subframe of the first and second subframes SF1 and SF2 of one frame to the data driver 4. The black data is supplied to the data driver 4 during the other one of the first and second subframes SF1 and SF2.

The subframe data generator 124 has a '127' gray value when the gray value of the input data Data 'is lower than the reference gray value Ref as shown in FIG. 6B. The sub-frame data RGB having a gray scale value of '255' is generated using the input data Data 'and supplied during one of the first and second sub-frames SF1 and SF2, and the first and second sub-frame data RGB are generated. Black data is supplied during the remaining subframes of the second subframes SF1 and SF2.

Also, as illustrated in FIG. 6C, when the grayscale value of the input data Data 'is smaller than the reference grayscale value Ref and higher than the intermediate grayscale, the subframe data generator 124 may input the data. To generate the sub frame data RGB having the maximum gray level value of '255' to be equal to the luminance of the same, and to supply it during one of the first and second sub frames SF1 and SF2 and to exceed the maximum gray level. The sub frame data RGB having the gray scale value is generated and supplied during the remaining sub frames of the first and second sub frames SF1 and SF2.

As a result, the subframe data generation unit 124 may double the grayscale value of the input data Data 'when the grayscale value of the input data Data' is lower than the reference grayscale value Ref to double the first and second values. The subframe is supplied to any one of the subframes SF1 and SF2 or divided into the first and second subframes SF1 and SF2.

Meanwhile, as illustrated in FIG. 6D, when the grayscale value of the input data Data 'is higher than the reference grayscale value Ref, the subframe data generator 124 may have a subframe equal to the grayscale value of the input data Data'. The frame data RGB is generated and supplied to each of the first and second subframes SF1 and SF2.

As such, when the grayscale value of the input data Data is lower than the reference grayscale value, the exemplary embodiment of the present invention increases the grayscale value of the input data Data by twice to generate and generate the subframe data RGB. The subframe data RGB is supplied to any one of the first and second subframes SF1 and SF2 of one frame, and the black data is supplied to the remaining subframes. At this time, the sub frame data RGB becomes equal to the luminance of the image displayed for one frame by the input data Data. As a result, when the grayscale value of the input input data Data is lower than the reference grayscale value, the exemplary embodiment displays the subframe data RGB in the form of an impulse.

According to an embodiment of the present invention, when the grayscale value of the input input data Data is higher than the reference grayscale value, the subframe data RGB that is the same as the grayscale value of the original input data Data is generated to generate the first frame of the frame. Supply to each of the first and second sub-frames (SF1, SF2). As a result, when the grayscale value of the input input data Data is higher than the reference grayscale value, the exemplary embodiment displays the subframe data RGB in a hold form.

Meanwhile, in the exemplary embodiment of the present invention, the image display unit has been described as having a liquid crystal cell that displays an image by adjusting light transmittance. However, the image display unit is not limited thereto, and a flat panel display including a liquid crystal display device and a light emitting display device driven in a hold form. It can be an image display of the device.

On the other hand, the present invention described above is not limited to the above-described embodiment and the accompanying drawings, it is possible that various substitutions, modifications and changes within the scope without departing from the technical spirit of the present invention It will be apparent to those skilled in the art.

The driving apparatus and the driving method of the image display apparatus according to the embodiment of the present invention as described above are driven in the form of an impulse in the case of input data having a gray scale value lower than the reference gray scale value and having a gray scale value higher than the reference gray scale value. In the case of data, the display device driven in the hold form can minimize the flow of motion of the display image without reducing the luminance in the hold device.

Claims (15)

An image display unit including pixel cells formed for each region defined by the plurality of gate lines and the plurality of data lines; In converting input data of one frame into two different subframe data or converting the input data of one frame into two subframe data identical to the input data of one frame, If the grayscale value of the input data is smaller than the reference grayscale value, when the input data is converted into two different subframe data, the grayscale value of the input data is amplified and controlled to be driven in an impulse form. If the grayscale value of the input data is smaller than the reference grayscale value but larger than the intermediate grayscale value, when the input data is converted into the two different subframe data, the grayscale value of the input data is amplified to the maximum grayscale value and impulse. A timing controller controlling to drive in a form; A gate driver for sequentially supplying scan pulses to gate lines for each subframe under the control of the timing controller; And a data driver for converting data of the sub-frame supplied from the timing controller into an analog video signal and supplying the data to the data lines under the control of the timing controller. The method of claim 1, And the reference gradation value is set within a range of 1/2 to 3/4 of the total gradation value of the input data. An image display unit including pixel cells formed for each region defined by the plurality of gate lines and the plurality of data lines; A timing controller for converting data of one frame into two different subframe data or converting the data of one frame into two subframe data identical to the data of one frame; A gate driver for sequentially supplying scan pulses to gate lines for each subframe under the control of the timing controller; And a data driver for converting data of the subframe supplied from the timing controller into an analog video signal and supplying the data to the data lines under the control of the timing controller. The timing controller, A control signal generator for generating a control signal for controlling each of the gate driver and the data driver; A data alignment unit for aligning input data of one frame to be suitable for driving the image display unit; And a data converter converting the sorted data into two different subframe data or the same subframe data according to the reference gray scale value and supplying the same data to the data driver. The method of claim 3, wherein The data converter, Generating a first comparison signal when the gray level value of the sorted data from the data alignment unit is lower than the reference gray level value, and generating a second comparison signal when the gray level value of the sorted data is higher than the reference gray level value A comparator; And a sub frame data generation unit configured to generate the two different sub frame data according to the first comparison signal or to generate the same two sub frame data according to the second comparison signal. Drive system. The method of claim 4, wherein The sub-frame data generation unit generates sub-frame data to be supplied to any one of the first and second sub-frames of one frame so as to have the same brightness as the sorted data according to the first comparison signal. And black data to be supplied to the remaining subframes of the first and second subframes. The method of claim 4, wherein The sub frame data generation unit may include sub frame data having a maximum luminance to be supplied to any one of the first and second sub frames of one frame such that the sub frame data generating unit has the same brightness as the aligned data according to the first comparison signal. And subframe data having remaining luminance to be supplied to the remaining subframes of the first and second subframes. The method of claim 4, wherein And the sub frame data generating unit generates the sub frame data which is equal to a gray level value of the aligned data to be supplied to each of the first and second sub frames of the one frame according to the second comparison signal. Drive of the device. The method of claim 4, wherein The period of the first and second sub-frames to which each of the two sub-frame data is supplied is the same as or different from each other in one frame. A driving method of an image display apparatus comprising an image display portion having a liquid crystal cell formed for each region defined by a plurality of gate lines and a plurality of data lines. In converting the input data of one frame input by using the reference gray scale value into two different subframe data or the same subframe data as the input data of one frame, When the grayscale value of the input data is smaller than the reference grayscale value, when the input data is converted into two different subframe data, the grayscale value of the input data is amplified and driven in an impulse form. If the grayscale value of the input data is smaller than the reference grayscale value but larger than the intermediate grayscale value, when the input data is converted into the two different subframe data, the grayscale value of the input data is amplified to the maximum grayscale value and impulse. Driving to form; Sequentially supplying scan pulses to gate lines for each subframe; And converting the data of the sub frame into an analog video signal and supplying the data lines to the data lines so as to be synchronized with the scan pulse. The method of claim 9, And the reference gradation value is set in a range of 1/2 to 3/4 of the total gradation value of the input data. A driving method of an image display apparatus comprising an image display portion having a liquid crystal cell formed for each region defined by a plurality of gate lines and a plurality of data lines. Converting data of one frame input using reference grayscale values into two different subframe data or two subframe data identical to the data of the one frame; Sequentially supplying scan pulses to gate lines for each subframe; Converting the data of the subframe into an analog video signal and supplying the data lines to be synchronized with the scan pulse. Converting the data of the one frame into the two sub frame data; Arranging input data of one frame to be suitable for driving the image display unit; Generating a first comparison signal when the gray level value of the sorted data is lower than the reference gray level value, and generating a second comparison signal when the gray level value of the sorted data is higher than the reference gray level value; And generating the two different sub-frame data according to the first comparison signal or the same two sub-frame data according to the second comparison signal. The method of claim 11, The generating of the two different subframe data may include subframes to be supplied to any one of the first and second subframes of one frame to have the same brightness as the aligned data according to the first comparison signal. And generating black data to be supplied to the remaining subframes of the first and second subframes. The method of claim 11, The generating of the two different subframe data may be performed to be supplied to any one of the first subframes and the second subframe of one frame to have the same luminance as the aligned data according to the first comparison signal. And generating subframe data having luminance and subframe data having remaining luminance to be supplied to the remaining subframes of the first and second subframes. The method of claim 11, The generating of the same two subframe data may include generating the subframe data which is equal to a gray value of the aligned data to be supplied to each of the first and second subframes of the one frame according to the second comparison signal. A driving method of an image display apparatus, characterized in that. The method of claim 11, The period of the first and second sub-frames to which each of the two sub-frame data is supplied is the same or different from each other in one frame.

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