Backlight driving method and backlight driving apparatus for scanning display

Abstract

A backlight driving method and a backlight driving device for a scanning display, the method is performed by the backlight driving device, comprising: sequentially receiving and temporarily storing K groups of data streams in an image data; when receiving the i-th group of data streams in the K groups of data streams, adjusting the i-th group of data streams with respect to the brightness of the display screen to generate an i-th adjustment signal output, 1≤i≤K; generating an internal synchronization control signal according to an original synchronization control signal, a delay signal output and the adjustment signal output, the original synchronization control signal having a square wave and the internal synchronization control signal having K square waves during an adjustment period of generating the adjustment signal output; and generating and outputting a backlight driving signal output to drive the scanning display to emit light according to the adjustment signal output and the internal synchronization control signal, so as to improve the problem of long frame delay of the existing backlight driving method for driving the backlight unit to emit light, thereby improving the display quality of the picture.

Description

Technical Field

[0001] This invention relates to a driving method and apparatus, and more particularly to a backlight driving method and backlight driving apparatus for a scanning display. Background Technology

[0002] An existing scanning liquid crystal display (LCD) system includes a control unit, a liquid crystal driving unit, a liquid crystal display panel, a backlight driving unit, and a backlight unit.

[0003] The control unit receives a serial input signal with an image stream. The image stream consists of multiple image data. Each image data corresponds to a frame displayed on the liquid crystal display panel and includes multiple data signals corresponding to the rotation of multiple rows of liquid crystal molecules on the liquid crystal display panel. The control unit sequentially receives the data signals of each image data and sequentially outputs them to the liquid crystal driving unit, so that the liquid crystal driving unit sequentially controls the rotation of each corresponding row of liquid crystal molecules in the liquid crystal display panel according to each data signal to display the frame corresponding to each image data. Simultaneously, the control unit sequentially copies and temporarily stores each data signal within itself. Specifically, taking the first image data as an example, the control unit sequentially receives the data signals of the first image data and sequentially outputs them to the liquid crystal driving unit, so that the liquid crystal driving unit sequentially controls the rotation of each corresponding row of liquid crystal molecules in the liquid crystal display panel according to each data signal to display the first image data. At the same time, the control unit sequentially copies and temporarily stores the data signals of the first image data within itself.

[0004] When the control unit finishes temporarily storing one of the image data (e.g., after temporarily storing all the data signals of the first image data), it adjusts the brightness of the displayed image data accordingly, generating an image data adjustment signal (e.g., the image data adjustment signal corresponding to the first image data). The control unit then transmits this image data adjustment signal and an original synchronization control signal related to the image update of each frame displayed on the liquid crystal display panel to the backlight driving unit. The backlight driving unit performs operations to drive the backlight unit to emit light based on the original synchronization control signal and each image data adjustment signal.

[0005] However, as described above, when the backlight driving unit drives the backlight unit to emit light according to the original synchronization control signal and the image data adjustment signal corresponding to the first image data, the liquid crystal display panel is already updating and displaying image data after the first image data. For example, when the backlight driving unit generates the image data adjustment signal corresponding to the first image data, the liquid crystal display panel is already updating and displaying the second image data of the image stream. When the backlight driving unit drives the backlight unit to emit light according to the original synchronization control signal and the image data adjustment signal corresponding to the first image data, the liquid crystal display panel is already updating and displaying the third image data of the image stream. This results in a long frame delay between the backlight unit and the liquid crystal display panel, causing image abnormalities in the image displayed on the liquid crystal display panel. Therefore, the existing backlight driving method for driving the backlight unit to emit light still has room for improvement. Summary of the Invention

[0006] One object of the present invention is to provide a backlight driving method for a scanning display that can overcome the shortcomings of the prior art.

[0007] The backlight driving method for a scanning display of the present invention is executed by a backlight driving device, and the backlight driving method for the scanning display includes the following steps:

[0008] (A) Receive and temporarily store K groups of data streams in a sequence of image data, the image data being related to a screen displayed by the scanning display, where K is a positive integer and K≥2;

[0009] (B) When the i-th data stream in the K data streams is received, the i-th data stream is adjusted with respect to the brightness of the display screen to generate an i-th adjustment signal output, l≤i≤K;

[0010] (C) Based on an initial synchronization control signal, a delayed signal output, and the adjustment signal output from step (B), an internal synchronization control signal is generated. The initial synchronization control signal is related to the image update of the screen displayed on the scanning display. During an adjustment period in which the adjustment signal output is generated, the initial synchronization control signal has a square wave, and the internal synchronization control signal has K square waves.

[0011] (D) Based on the adjustment signal output and the internal synchronization control signal, a backlight driving signal is generated and output to the scanning display to drive the scanning display to emit light, such that the light emission sequence of the scanning display during the adjustment period changes with the appearance of the K square waves of the internal synchronization control signal.

[0012] The present invention relates to a backlight driving method for a scanning display.

[0013] The delayed signal output has K predetermined delay values, and

[0014] The starting point of the square wave of the original synchronization control signal appears after the first adjustment signal output is generated. The starting points of the K square waves of the internal synchronization control signal appear after a corresponding one of the adjustment signal outputs is generated. The starting point of each square wave of the internal synchronization control signal has a time difference with an ending point of the square wave of the original synchronization control signal, and the time difference is respectively related to the K predetermined delay values.

[0015] The present invention relates to a backlight driving method for a scanning display.

[0016] The delayed signal output has K predetermined delay values, and

[0017] In step (C), the i-th square wave of the internal synchronization control signal is generated based on the original synchronization control signal, the i-th predetermined delay value among the K predetermined delay values, and the i-th adjustment signal output among the adjustment signal outputs.

[0018] The backlight driving method of the scanning display of the present invention has a difference between adjacent K predetermined delay values, and each difference is the same in magnitude.

[0019] The backlight driving method of the scanning display of the present invention has a difference between adjacent K predetermined delay values, and each difference is of a different magnitude.

[0020] The backlight driving method of the scanning display of the present invention has a first predetermined delay value of zero among the K predetermined delay values.

[0021] Another object of the present invention is to provide a backlight driving device for a scanning display that can overcome the shortcomings of the prior art.

[0022] The backlight driving device of the scanning display of the present invention includes a control unit and a backlight driving unit.

[0023] The control unit sequentially receives and temporarily stores K sets of data streams in an image data, which are related to a screen displayed by the scanning display. K is a positive integer, K≥2. When the i-th data signal in the K sets of data streams is received, the control unit adjusts the i-th data signal with respect to the brightness of the display screen to generate and output an i-th adjustment signal, 1≤i≤K. When i=1, the control unit also generates and outputs an original synchronization control signal and a delay signal.

[0024] The backlight driving unit is electrically connected to the control unit to receive the original synchronization control signal, the delay signal output, and the adjustment signal output, and generates an internal synchronization control signal accordingly. The original synchronization control signal is related to the image update of the screen displayed on the scanning display. During an adjustment period in which the adjustment signal output is generated, the original synchronization control signal has a square wave, and the internal synchronization control signal has K square waves. The backlight driving unit also generates and outputs a backlight driving signal to the scanning display according to the adjustment signal output and the internal synchronization control signal to drive the scanning display to emit light, such that the light emission sequence of the scanning display during the adjustment period changes with the appearance of the K square waves of the internal synchronization control signal.

[0025] The present invention relates to a backlight driving device for a scanning display.

[0026] The delayed signal output has K predetermined delay values, and

[0027] The starting point of the square wave of the original synchronization control signal appears after the first adjustment signal output is generated. The starting points of the K square waves of the internal synchronization control signal appear after a corresponding one of the adjustment signal outputs is generated. The starting point of each square wave of the internal synchronization control signal has a time difference with an ending point of the square wave of the original synchronization control signal, and the time difference is respectively related to the K predetermined delay values.

[0028] The backlight driving device of the scanning display of the present invention has a delay signal output having K predetermined delay values. The backlight driving unit generates the i-th square wave of the K square waves of the internal synchronization control signal according to the original synchronization control signal, the i-th predetermined delay value among the K predetermined delay values, and the i-th adjustment signal output among the adjustment signal outputs.

[0029] The backlight driving device of the scanning display of the present invention has a difference between adjacent K predetermined delay values, and each difference may be the same or different.

[0030] The advantage of this invention is that by adjusting the brightness of the display screen when the i-th data signal in the K-group data stream is received, and generating a corresponding adjustment signal output, the relevant operation of driving the scanning display to emit light can be performed. This can improve the long frame delay problem of the existing backlight driving method for driving the backlight unit to emit light, thereby improving the display quality. Attached Figure Description

[0031] Other features and effects of the present invention will be clearly presented in the embodiments with reference to the accompanying drawings, wherein:

[0032] Figure 1This is a block diagram illustrating an embodiment of the backlight driving device for the scanning display of the present invention;

[0033] Figure 2 This is a flowchart illustrating how the backlight driving device of this embodiment performs the backlight driving method of the scanning display of the present invention; and

[0034] Figure 3 This is a timing diagram illustrating the output timing of an initial synchronization control signal, an adjustment signal, and an internal synchronization control signal in this embodiment. Detailed Implementation

[0035] See Figure 1 This invention discloses an embodiment of a backlight driving device 2 for a scanning display 1, suitable for driving the scanning display 1. The scanning display 1 is a liquid crystal display supporting a dynamic frame rate, and includes a backlight unit 11, a liquid crystal driving unit 12, and a liquid crystal display panel 13. The backlight driving device 2 executes the backlight driving method of the scanning display 1 of this invention to drive the backlight unit 11 to emit light.

[0036] The backlight unit 11 includes multiple switches (not shown) and an array of light-emitting diodes (not shown) including multiple light-emitting diodes (LEDs). The configuration of the backlight unit 11 is well known to those skilled in the art and will not be described in detail here for the sake of brevity.

[0037] In this embodiment, the backlight driving device 2 includes a control unit 21 electrically connected to the liquid crystal driving unit 12, and a backlight driving unit 22 electrically connected between the control unit 21 and the backlight unit 11.

[0038] The control unit 21 is used to receive a serial input signal SDI having an image stream. The image stream consists of a plurality of image data transmitted sequentially. Each image data is related to a screen displayed on the liquid crystal display panel 13 of the scanning display 1, and includes K groups of data streams, where K is a positive integer and K≥2. Each group of data streams includes a plurality of data signals transmitted sequentially. During the updating and displaying of the screen by the liquid crystal display panel 13, the data signals of the K groups of data streams serve as data required for the rotation of multiple rows (a row is defined as a horizontal row in an array) of liquid crystal molecules in the liquid crystal display panel 13. In simple terms, the control unit 21 sequentially receives and outputs the data signals included in the K groups of data streams of one of the image data to the liquid crystal driving unit 12, so that the liquid crystal driving unit 12 sequentially controls the rotation of the corresponding row of liquid crystal molecules in the liquid crystal display panel 13 according to each data signal to display the screen corresponding to that image data. This is well known to those skilled in the art and will not be described in detail here.

[0039] Further reading Figure 2 and Figure 3 In this embodiment, the control unit 21 cooperates with the backlight driving unit 22 to repeatedly execute a backlight driving method including the steps 31 to 35 according to each image data of the image stream of the serial input signal SDI, so as to drive the backlight unit 11 to emit light.

[0040] In step 31, the control unit 21 sequentially receives and temporarily stores the K groups of data streams of the image data.

[0041] In step 32, when the i-th data stream in the K data streams is received, the control unit 21 adjusts the brightness of the i-th data stream with respect to the brightness of the display screen, so as to generate and output an i-th adjustment signal output Dri, 1≤i≤K.

[0042] Figure 3 The symbol As shown represents an adjustment signal output timing. For example, Figure 3Taking K=3 as an example, when the first data stream of the K groups of data streams of the image data is received, the control unit 21 adjusts the brightness of the first data stream with respect to the display screen brightness to generate and output a first adjustment signal output Dr1 (i.e., the first period As11 of the adjustment signal output timing As). When the second data stream of the K groups of data streams of the image data is received, the control unit 21 adjusts the brightness of the second data stream with respect to the display screen brightness to generate and output a second adjustment signal output Dr2 (i.e., the second period As12 of the adjustment signal output timing As). When the third data stream of the K groups of data streams of the image data is received, the control unit 21 adjusts the brightness of the third data stream with respect to the display screen brightness to generate and output a third adjustment signal output Dr3 (i.e., the third period As13 of the adjustment signal output timing As).

[0043] In step 33, when i = 1, the control unit 21 generates and outputs an initial synchronization control signal EVsync and a delay signal output De with K predetermined delay values. The initial synchronization control signal EVsync is related to the image update of the screen displayed on the liquid crystal display panel 13.

[0044] In step 34, the backlight driving unit 22 generates an internal synchronization control signal IVsync based on the original synchronization control signal EVsync, the delay signal output De, and the adjustment signal outputs Dr1 to Dr3.

[0045] In this embodiment, during an adjustment period Ap during which the adjustment signal outputs Dr1 to Dr3 are generated, the original synchronization control signal EVsync has a square wave, and the internal synchronization control signal IVsync has three square waves. Figure 3(Taking K=3 as an example). Specifically, the backlight driving unit 22 generates the i-th square wave of the three square waves of the internal synchronization control signal IVsync based on the original synchronization control signal EVsync, the i-th predetermined delay value among the three predetermined delay values, and the i-th adjustment signal output among the adjustment signal outputs Dr1 to Dr3. The starting point of the square wave of the original synchronization control signal EVsync appears after the generation of the first adjustment signal output Dr1. The starting points of each of the three square waves of the internal synchronization control signal IVsync appear after the generation of a corresponding one of the adjustment signal outputs Dr1 to Dr3. The starting points of the three square waves of the internal synchronization control signal IVsync and the ending points of the square waves of the original synchronization control signal EVsync have time differences t1, t2, and t3, respectively, and these time differences t1, t2, and t3 are respectively related to the three predetermined delay values. It should be noted that in this embodiment, there is a difference between any two adjacent values ​​among the three predetermined delay values, and each difference is of the same magnitude (i.e., the difference between any two adjacent values ​​in the time differences t1 to t3 is of the same magnitude), but this is not limited to this. In other embodiments, each difference is of a different magnitude (i.e., the difference between any two adjacent values ​​in the time differences t1 to t3 is different magnitude), or the first predetermined delay value among the three predetermined delay values ​​is zero (i.e., the time difference t1 is zero).

[0046] In step 35, the backlight driving unit 22 generates and outputs a backlight driving signal Do to the backlight unit 11 of the scanning display 1 according to the adjustment signal output Dr1~Dr3 and the internal synchronization control signal IVsync, so as to drive the backlight unit 11 to emit light, so that the scanning light emission sequence of the backlight unit 11 corresponding to the screen during the adjustment period Ap changes with the appearance of the K square waves of the internal synchronization control signal IVsync.

[0047] For example, the LED array of the backlight unit 11 is a 9×5 array. Each image data includes three (i.e., K=3 for example) sets of data streams, and each set of data streams includes three data signals transmitted sequentially. The nine data signals of the three sets of data streams serve as the basis for adjusting the brightness of the nine rows (a row is defined as a horizontal row in the array) of LEDs in the backlight unit 11. Thus, when the first square wave of the three square waves of the internal synchronization control signal IVsync appears, the backlight driving unit 22 generates the backlight driving signal output Do according to the adjustment signal output Dr1 to drive the first to third rows of LEDs in the backlight unit 11 to emit light. When the second square wave of the three square waves of the internal synchronization control signal IVsync appears, the backlight driving unit 22 generates the backlight driving signal output Do according to the adjustment signal outputs Dr1 and Dr2 to drive the first to sixth rows of LEDs in the backlight unit 11 to emit light. When the third square wave of the three square waves of the internal synchronization control signal IVsync appears, the backlight driving unit 22 generates the backlight driving signal output Do according to the adjustment signal output Dr1 to Dr3 to drive the first to ninth rows of light-emitting diodes of the backlight unit 11 to emit light.

[0048] In summary, the backlight driving method of the scanning display of the present invention adjusts the brightness of the display screen upon receiving one of the K sets of data streams of the image data, and generates a corresponding adjustment signal output Dri. Then, based on the corresponding adjustment signal output Dri, the original synchronization control signal EVsync, and the delay signal output De, a square wave corresponding to the internal synchronization control signal IVsync is generated. As a result, the backlight driving unit 22 is controlled by the corresponding square wave of the internal synchronization control signal IVsync, and drives the backlight unit 11 to emit light according to the corresponding adjustment signal outputs Dr1 to Dri. Compared with the prior art, which adjusts the brightness of the display screen and drives the backlight unit to emit light only upon receiving all the data signals of one of the image data, the backlight driving method of the scanning display of the present invention can improve the situation where the image displayed on the liquid crystal display panel is abnormal due to the long frame delay problem in the prior art, thereby improving the image display quality.

[0049] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the present invention. Any simple equivalent changes and modifications made in accordance with the claims and description of the present invention shall still fall within the scope of the present invention.

Claims

1. A backlight driving method for a scanning display, executed by a backlight driving device, characterized in that, The backlight driving method for this scanning display includes the following steps: (A) Receive and temporarily store K sets of data streams in the image data in sequence, wherein the image data is related to the screen displayed by the scanning display, K is a positive integer, K≥2; (B) When the i-th data stream in the K data streams is received, the i-th data stream is adjusted with respect to the brightness of the display screen to generate the i-th adjustment signal output, 1≤i≤K; (C) An internal synchronization control signal is generated based on the original synchronization control signal, the delay signal output, and the adjustment signal output of step (B). The original synchronization control signal is related to the image update of the screen displayed on the scanning display. During the adjustment period of generating the adjustment signal output, the original synchronization control signal has a square wave, the internal synchronization control signal has K square waves, and the delay signal output has K predetermined delay values. The start point of the square wave of the original synchronization control signal appears after the first adjustment signal output of the adjustment signal output. The start point of each of the K square waves of the internal synchronization control signal appears after a corresponding one of the adjustment signal outputs is generated. The start point of each square wave of the internal synchronization control signal has a time difference with the end point of the square wave of the original synchronization control signal, and the time difference is related to the K predetermined delay values ​​respectively. and (D) Based on the adjustment signal output and the internal synchronization control signal, a backlight driving signal is generated and output to the scanning display to drive the scanning display to emit light, such that the light emission sequence of the scanning display during the adjustment period changes with the appearance of the K square waves of the internal synchronization control signal.

2. The backlight driving method for a scanning display according to claim 1, characterized in that, The delayed signal output has K predetermined delay values, and In step (C), the i-th square wave of the internal synchronization control signal is generated based on the original synchronization control signal, the i-th predetermined delay value among the K predetermined delay values, and the i-th adjustment signal output among the adjustment signal outputs.

3. The backlight driving method for a scanning display according to claim 2, characterized in that, There is a difference between any two adjacent values ​​of the K predetermined delay values, and each difference is the same in magnitude.

4. The backlight driving method for a scanning display according to claim 2, characterized in that, There is a difference between adjacent values ​​of the K predetermined delay values, and each difference is of a different magnitude.

5. The backlight driving method for a scanning display according to claim 2, characterized in that, The first of the K predetermined delay values ​​is zero.

6. A backlight driving device for a scanning display, characterized in that, Include: The control unit sequentially receives and temporarily stores K sets of data streams in the image data. The image data is related to the screen displayed by the scanning display. K is a positive integer, K≥2. When the i-th set of data streams is received, the control unit adjusts the i-th set of data streams with respect to the brightness of the display screen to generate and output an i-th adjustment signal, 1≤i≤K. When i=1, the control unit also generates and outputs an original synchronization control signal and a delay signal. and A backlight driving unit, electrically connected to the control unit, receives the original synchronization control signal, the delay signal output, and the adjustment signal output, and generates an internal synchronization control signal accordingly. The original synchronization control signal is related to the image update of the screen displayed on the scanning display. During an adjustment period in which the adjustment signal output is generated, the original synchronization control signal has a square wave, and the internal synchronization control signal has K square waves. The backlight driving unit also generates and outputs a backlight driving signal to the scanning display based on the adjustment signal output and the internal synchronization control signal, thereby driving the scanning display to emit light. The order in which the scanning display emits light during the adjustment period varies with the appearance of the K square waves of the internal synchronization control signal. The delayed signal output has K predetermined delay values. The start point of the square wave of the original synchronization control signal appears after the first adjustment signal output is generated. The start points of each of the K square waves of the internal synchronization control signal appear after a corresponding one of the adjustment signal outputs is generated. The start point of each square wave of the internal synchronization control signal has a time difference with an end point of the square wave of the original synchronization control signal, and the time difference is respectively related to the K predetermined delay values.

7. The backlight driving device for a scanning display according to claim 6, characterized in that, The delayed signal output has K predetermined delay values. The backlight driving unit generates the i-th square wave of the K square waves of the internal synchronization control signal based on the original synchronization control signal, the i-th predetermined delay value among the K predetermined delay values, and the i-th adjustment signal output among the adjustment signal outputs.

8. The backlight driving device for a scanning display according to claim 7, characterized in that, There is a difference between adjacent values ​​of the K predetermined delay values, and each difference may be the same or different.

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