TWI768706B - Scanning display and its driving device - Google Patents

Abstract

A scanning type display includes a backlight module with a common anode structure, a display module, a control module and a driving module, the backlight module includes a plurality of scanning lines and a plurality of data lines respectively correspondingly disposed on the A plurality of light emitting diodes between the defined matrices. The control module generates a plurality of switching signals corresponding to the plurality of scan lines to the backlight module according to the synchronization control signal and the image stream, so as to control the backlight module to transmit the input voltage to the scan lines of each row , the control module also generates an image update signal according to the synchronization control signal and the switching signal of the scan line corresponding to the last row, and the image update signal is related to the image update of the display module.

Description

Scanning display and its driving device

The present invention relates to a display technology in the field of light emitting diodes, in particular to a scanning display and a driving device thereof.

A conventional driving device for driving a scanning display to display images includes a control module and a driving module. The driving module receives a synchronization control signal related to image display and updating from the control module, and receives an image stream from the control module. The image stream has a plurality of image data related to the picture to be displayed by the scanning display. The driving module drives the scanning display according to the synchronization control signal and the image stream, so that a backlight module including a light-emitting diode array in the scanning display is controlled by the synchronization control signal. At the same time, it becomes brighter or darker, and a display module in the scanning display performs image display and update of the image data of the image stream according to the frequency of the synchronization control signal. The synchronization control signal is a vertical synchronization (V-sync) periodic signal, and its frequency is, for example, 60 Hz, that is to say, the scanning display will periodically update the displayed picture. A screen frame rate is the same as the frequency of the synchronization control signal.

However, when the synchronization control signal is an aperiodic signal, and the backlight module is a scanning backlight module that is triggered by the synchronization control signal and adopts scanning control to emit light row by row in sequence, the above-mentioned conventional scanning display The driving method may cause tearing or interruption of the picture displayed by the display module. Therefore, there is still room for improvement in the driving method of the existing scanning display.

Therefore, a first objective of the present invention is to provide a scanning display that can avoid tearing or interruption of the picture displayed by the scanning display.

Therefore, the scanning display includes a backlight module and a display module.

The backlight module receives an input voltage and includes a light-emitting diode array with a common anode structure. The light-emitting diode array includes: a plurality of scanning lines arranged along a row direction with each other, a plurality of scanning lines arranged perpendicular to each other along a column direction data lines of the line, a plurality of light-emitting diodes respectively disposed between the plurality of scan lines and the matrix defined by the plurality of data lines, and each light-emitting diode has an electrical connection corresponding to the scan line The anode of the line, and the cathode of the data line corresponding to an electrical connection. The display module is used for displaying images. The driving device includes a control module and a driving module. The control module generates an image stream and a synchronization control signal, and generates a plurality of switching signals corresponding to the plurality of scan lines to the backlight module according to the synchronization control signal and the image stream to control the backlight module. The backlight module transmits the input voltage to the scan lines of each row, so that the backlight module emits light in a row scanning manner, and the control module also generates a an image update signal, the image update signal is related to the image update of the display module.

The driving module is electrically connected to the backlight module and the display module, and is electrically connected to the control module to receive the synchronization control signal and the image stream. and the image update signal, the driving module also generates an output signal to the display module according to the image update signal and the image stream to drive the display module to display and update the image, so that the The display module updates the displayed image following the change of the image update signal.

Preferably, a driving method for a scanning display is executed by a driving device, and the driving method for the scanning display includes the following steps: (A) the control module generates an image stream. (B) The control module generates a synchronous control signal. (C) The control module generates a plurality of switching signals corresponding to a plurality of scan lines to the backlight module, so as to control the backlight module to transmit the input voltage to the scan lines of each row. (D) The control module generates an image update signal according to the synchronization control signal and the input voltage output to the scan line of the last row, and the image update signal is related to the image update of the scanning display.

The second object of the present invention is to provide a scanning display that emits light directly without liquid crystal display.

Therefore, the scanning display includes a light-emitting diode direct display module and a driving device.

The LED direct display module receives an input voltage and includes a plurality of scan lines arranged along a row direction with each other, a plurality of data lines arranged perpendicular to the scan lines along a column direction with each other, and a plurality of data lines arranged correspondingly to each other on the scan lines. Light-emitting diodes between the matrix defined by the plurality of scan lines and the plurality of data lines, each light-emitting diode has an anode of the scan line corresponding to an electrical connection, and an electrical connection corresponding to the anode The cathode of the data line. The driving device includes a control module and a driving module.

The control module generates an image stream and a synchronization control signal, and generates a plurality of switching signals corresponding to the plurality of scan lines to the backlight module according to the synchronization control signal and the image stream to control the backlight module. The backlight module transmits the input voltage to the scan line of each row, scans the backlight module line, and the control module also generates an image update according to the synchronization control signal and the switching signal of the scan line corresponding to the last row Signal.

The drive module is electrically connected to the LED direct display module, and is electrically connected to the control module to receive the synchronization control signal and the image stream, and the drive module is connected to the image stream according to the image update signal The flow generates a plurality of driving signals to the plurality of data lines of the LED direct display module.

The effect of the present invention is that the circuit structure used to drive the light emitting diode (LED) array of the common anode structure not only greatly reduces the trouble of system heat dissipation, but also avoids the need for image display and update according to the image update signal. The picture displayed by the display module is suddenly cut off due to the synchronization control signal, so that the display module will not have the situation of image tearing or interruption.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are designated by the same reference numerals.

Referring to FIGS. 1 and 2 , an embodiment of the scanning display of the present invention is suitable for image display. The scanning display (eg, a liquid crystal display) supports a dynamic frame rate and includes a backlight module 11 , a display module 12 (eg, a liquid crystal display panel) for displaying images, and a Drive 2.

The backlight module 11 includes a common anode structure light emitting diode array and a scanning unit SU. The light emitting diode array includes: a plurality of scan lines arranged along a row direction with each other, a plurality of data lines arranged perpendicular to the scan lines along a column direction with each other, and a plurality of light emitting diodes 116 . A plurality of light emitting diodes 116 are respectively disposed between the matrix defined by the plurality of scan lines and the plurality of data lines, and each light emitting diode 116 has an anode electrically connected to the corresponding scan line, and a cathode that is electrically connected to the corresponding data line.

The scanning unit SU receives a plurality of switching signals SW1 ˜ SW3 and the input voltage Vin, is electrically connected to each scanning line of the backlight module 11 , and is controlled by the plurality of switching signals SW1 ˜ SW3 to sequentially output the input voltage Vin to the scan lines of each row of the backlight module 11 . The scan unit SU includes a plurality of scan switches S1 to S3 corresponding to the plurality of scan lines, each scan switch has a first end for receiving the input voltage Vin, and a second end electrically connected to the corresponding scan line , and a control terminal that receives the corresponding switching signal, and switches between conducting and non-conducting according to the switching signal, and the scanning unit SU and the LED array are integrated into a single chip.

The driving device 2 includes a control module 21 and a driving module 22 .

The control module 21 generates a synchronization control signal VSYNC, and an internal graphics processing unit (GPU, not shown) generates an image stream Dr with a plurality of image data Draw. The image stream Dr is related to the picture to be displayed by the display module 12 . In this embodiment, the control module 21 sequentially outputs the image data as the image stream Dr, and according to a synchronization control signal VSYNC, the image stream Dr generates a plurality of corresponding to the plurality of The switching signals SW1 to SW3 of the scan lines are sent to the backlight module 11 to control the backlight module 11 to transmit the input voltage Vin to the scan lines of each row, so that the backlight module 16 emits light in a row scanning manner. The group 21 also generates an image update signal Draw_update according to the synchronization control signal VSYNC and the switching signal SW3 corresponding to the scan line of the last row, and the image update signal Draw_update is related to the image update of the display module 12 .

The driving module 22 is electrically connected to the backlight module 11 and the display module 12, and is electrically connected to the control module 21 to receive the synchronization control signal VSYNC, the image stream Dr, and the image update signal Draw_update , and drive the backlight module 11 and the display module 12 accordingly. The driving module 22 also generates an output signal Do to the display module 12 according to the image update signal Draw_update and the image stream Dr, so as to drive the display module 12 to perform image display and update, so that the display The module 12 updates the displayed image following the change of the image update signal Draw_update.

In this embodiment, the driving module 22 includes a storage unit 221 , a first driving signal generator 222 , and a second driving signal generator 223 .

The first driving signal generator 222 has a phase-locked loop circuit for generating the clock signal, and the first driving signal generator 222 is electrically connected to the plurality of data lines of the backlight module 16 , the control module 21 and the storage The unit 221 receives the image update signal Draw_update from the control module 21 and the image stream from the storage unit 221, and generates a plurality of driving signals according to the image update signal Draw_update and the image stream D1-D3 are connected to the plurality of data lines of the light-emitting diode array, and also generate an update signal according to the image update signal. The second driving signal generator 223 is electrically connected to the first driving signal generator 222 to receive the update signal, and generate the output signal Do according to the update signal and the image stream Dr. It should be noted that the second driving signal generator 223 is a driving circuit including a source driver and a gate driver, and is well known to those skilled in the art, so it is not repeated here.

The storage unit 221 is electrically connected to the control module 21 and the first and second driving signal generators 222 and 223 , and receives and temporarily stores the image stream Dr from the control module 21 . The storage unit 22 has two memories SRAMA and SRAMB for temporarily storing the image data Draw1 to Draw4 of the image stream Dr, that is, the image data temporarily stored in SRAMA and SRAMB are displayed in turn. It is further explained here that the image data Draw1 is displayed after the first Draw_update, and the image data Draw2 is temporarily stored in the memory SRAMB; after the second Draw_update, the image data Draw2 is displayed, and the image data Draw3 is temporarily stored in the memory. SRAMA; After the third Draw_update, the image data Draw3 is displayed, and the image data Draw4 is temporarily stored in the memory SRAMB; and so on.

Referring to FIG. 3 , the driving module 22 executes a driving method of a scanning display to drive the scanning display to perform image display and update. The driving method includes a step S, a step A, a step B, a step C, a One step D, one step E.

In step S, the phase-locked loop circuit 224 of the driving signal generator 222 of the driving module 22 generates the clock signal.

In step A, the storage unit 221 of the driving module 22 receives the image stream Dr generated from the control module 21 and temporarily stores the image stream Dr.

In step B, the driving signal generator 222 of the driving module 22 receives the synchronization control signal VSYNC generated from the control module 21 and the image stream Dr from the storage unit 221 respectively.

In step C, the control module 2 generates a plurality of switching signals corresponding to a plurality of scan lines to the backlight module 11 to control the backlight module 11 to transmit the input voltage Vin to the scan lines of each row, so that The backlight module 11 emits light in a line scanning manner. As shown in FIG. 4 , this step C includes the following sub-steps 341 to 343 .

In sub-step C1, the control module 2 generates the switching signals SW1-SW3 according to the synchronization control signal VSYNC and the clock signal. In this embodiment, each of the switching signals SW1 ˜ SW3 is a pulse signal having a plurality of square waves, and the pulse width thereof is an integer multiple of a period of the clock signal. In each scanning period of the backlight module 11, the pulses of the switching signals SW1-SW3 are interleaved. In addition, the first pulse of the synchronization control signal VSYNC triggers the switching of the switching signals SW1 ˜ SW3 .

In sub-step C2, the driving signal generator 222 generates the driving signals D1-Dn according to the image stream Dr and the clock signal. In this embodiment, each of the driving signals D1 ˜Dn is a pulse wave signal having a plurality of square waves, and the pulse wave width thereof is an integer multiple of the period of the clock signal, and the The integer multiple varies with the image stream Dr.

In sub-step C3, the control module 2 outputs the switching signals SW1-SW3 to the control terminals of the scan switches S1-S3, respectively.

In step D, the control module 2 generates and outputs an image update signal Draw_update to the synchronous control signal VSYNC and the last switching signal (ie, the switching signal SW3 ) among the switching signals SW1 ˜ SW3 . For the driving signal generator 222 , the image update signal Draw_update is related to the image update of the display module 12 of the scanning display 1 .

In this embodiment, as shown in FIG. 2 , the last switching signal SW3 corresponds to the last line of the line scanning performed by the scanning display 1 when emitting light. Each of the synchronization control signal VSYNC and the image update signal Draw_update is a pulse wave signal with a plurality of square waves. Each square wave of the image update signal Draw_update lags behind a corresponding square wave of the synchronization control signal VSYNC, and a start point of each square wave except the first square wave in the image update signal Draw_update and the switching signal SW3 ( That is, an end point of a square wave of the last switching signal among the switching signals SW1 to SW3 occurs simultaneously. The end point of the square wave of the switching signal SW3 occurs immediately after a start point of the corresponding square wave of the synchronization control signal VSYNC.

In step E, the first driving signal generator 222 of the driving module 22 further generates an update signal to the second driving signal generator 223 according to the image update signal Draw_update, and the first driving signal of the driving module 22 The signal generator 222 outputs the driving signals D1 to Dn to the cathodes of the plurality of light-emitting diodes 116 in the light-emitting diode array according to the image update signal Draw_update, so as to drive the backlight module 11 . The light-emitting diode array emits light row by row. It should be noted that each row in the row-by-row light emission of the light-emitting diode array of the backlight module 11 is defined as each column in the light-emitting diode array (ie, each horizontal row) of light-emitting diodes 116 . The driving signal generator 223 of the driving module 22 generates and outputs an output signal Do to the display mode of the scanning display 1 according to the update signal and the image stream Dr temporarily stored in the storage unit 221 The group 12 is used to drive the display module 12 to perform image display and update according to the output signal Do, so that the display module 12 updates the displayed image following the change of the image update signal Draw_update.

It should be added that, in this embodiment, step S is performed before step A, but it is not limited to this. In other embodiments, step S may also be performed between step A and step B, or performed between step B and step C.

As shown in FIG. 5 , a second embodiment of the scanning display 1 of the present invention is a direct display without liquid crystal display. The difference from the first embodiment is that there is no display module like a liquid crystal display panel, but a A LED direct display module 10 replaces the backlight module 11 of the first embodiment; and the driving module of the second embodiment does not include the second driving signal generator 223, but the first driving signal generator 223 is based on The image update signal Draw_update from the control module 21 determines the timing of outputting the driving signals D1 to Dn to the LED direct display module 10 .

To sum up, the above embodiments have the following advantages:

1. The mainstream light-emitting diode display applications in the market are light-emitting diode (LED) arrays with a common anode structure occupying the largest proportion, so that the driving device in this case has high product versatility and lower costs. 2. If the line scan signals (SW1~SW3) are output by the control module 21, the digital timing design of the driving module can be simplified, and the number of pins used for transmission with the external switches S1~S3 can be reduced.

3. Since the scanning unit and the driver module are not integrated into a single chip, the design of the driver module is more flexible, allowing users to more flexibly match the number of LEDs to be loaded; it can also be distributed evenly The heat of the driver module reaches the external scanning unit (line scan MOS), so that the temperature will not be concentrated on the same driver chip, which greatly reduces the trouble of system heat dissipation.

4. The driving method is to make the display module 12 update the displayed image according to the change of the image update signal Draw_update, that is to say, the picture displayed by the display module 12 will be displayed in the backlight module 11 After the corresponding last line scan is completed (ie, corresponding to an end point of a corresponding one of the square waves of the switching signal SW3 ), the displayed picture will be updated, and then the display module 12 will display the displayed image. The picture will not be updated when the line scan corresponding to the backlight module 11 is not finished due to the synchronization control signal VSYNC, so that the picture displayed by it can be prevented from being suddenly cut off and the situation of image tearing or interruption occurs. Therefore, the driving method of the scanning display of the present invention has better picture display compared with the driving method of the existing display (which causes picture tearing or interruption due to the image display and update according to the synchronization control signal VSYNC).

However, the above are only examples of the present invention, and should not limit the scope of implementation of the present invention. Any simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the contents of the patent specification are still included in the scope of the present invention. within the scope of the invention patent.

10: LED direct display module 11: Backlight module SU: Scanning Unit S1~S3: Scan switch 116: Light Emitting Diode 12: Display module 2: drive unit 21: Control module 22: Driver module 221: storage unit 222: first drive signal generator 223: second drive signal generator 224: Phase Locked Loop Circuit S~E: Steps C1~C3: Substeps D1~Dn: drive signal Do: output signal Dr: Image Streaming Draw: Image data SW1~SW3: switch signal t: time Vin: input voltage Draw_update: image update signal VSYNC: Synchronization control signal

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, wherein: 1 is a circuit diagram of a first embodiment of a scanning display of the present invention; 2 is a timing diagram of the first embodiment; 3 is a flowchart of a driving method for a scanning display performed by a driving module of the first embodiment; 4 is a flow chart of the driving method for emitting light in a row scanning manner to the backlight module; and 5 is a circuit diagram of a second embodiment of a scanning display of the present invention.

11: Backlight module

SU: Scanning Unit

S1~S3: Scan switch

116: Light Emitting Diode

12: Display module

2: drive unit

21: Control module

22: Driver module

221: storage unit

222: first drive signal generator

223: second drive signal generator

224: Phase Locked Loop Circuit

Claims (11)

A scanning type display, comprising: a backlight module, receiving an input voltage and comprising a light-emitting diode array with a common anode structure, the light-emitting diode array includes: a plurality of scanning lines, arranged along a row direction with each other, a plurality of data Lines are arranged perpendicular to the scan lines along a column direction, a plurality of light emitting diodes are respectively correspondingly arranged between the matrix defined by the plurality of scan lines and the plurality of data lines, each light emitting diode There is an anode electrically connected to the corresponding scan line, and a cathode electrically connected to the corresponding data line; a display module for displaying images; a driving device, including: a control module to generate a an image stream, and a synchronization control signal, and according to the synchronization control signal and the image stream, a plurality of switching signals corresponding to the plurality of scan lines are generated to the backlight module to control the backlight module to The input voltage is transmitted to the scan lines of each row, and the control module also generates an image update signal according to the synchronization control signal and the switching signal corresponding to the scan line of the last row, and the image update signal is related to the display module image update; and a driving module, electrically connected to the backlight module and the display module, and electrically connected to the control module to receive the synchronization control signal and the image stream and the image update signal, the The driving module also updates the signal according to the image and the image string stream to generate an output signal to the display module to drive the display module to perform image display and update, so that the display module follows the change of the image update signal to update the displayed image. The scanning display of claim 1, wherein the driving module comprises: a storage unit electrically connected to the control module to receive the image stream and temporarily store the image stream, a first driver a signal generator, electrically connected to the plurality of data lines of the backlight module, the control module and the storage unit, to receive the image update signal from the control module and the image stream from the storage unit , and generate a plurality of driving signals to the data lines of the light-emitting diode array according to the image update signal and the image stream, and also generate an update signal according to the image update signal, and a second The driving signal generator is electrically connected to the first driving signal generator to receive the update signal, and generate the output signal according to the update signal and the image stream. The scanning display of claim 2, wherein the first driving signal generator has a phase-locked loop circuit that generates a clock signal. The scanning display of claim 1, wherein the backlight module comprises: a scanning unit that receives a plurality of switching signals and the input voltage and is electrically connected to each scanning line of the backlight module, and receives the plurality of switching signals and the input voltage. The switching signal is controlled to sequentially output the input voltage to the scan lines of each row of the backlight module. The scanning display according to claim 4, wherein the scanning unit comprises a plurality of scanning switches corresponding to the plurality of scanning lines, and each scanning switch It has a first end that receives the input voltage, a second end that is electrically connected to the corresponding scan line, and a control end that receives the corresponding switching signal, and switches between conducting and non-conducting according to the switching signal , and the scanning unit and the light-emitting diode array are integrated into a single wafer. A driving device for a scanning display, the scanning display includes a backlight module and a display module, the backlight module receives an input voltage and includes a light-emitting diode array with a common anode structure, the driving device includes: a control The module generates an image stream and a synchronization control signal, and generates a plurality of switching signals corresponding to a plurality of scanning lines to the backlight module according to the synchronization control signal and the image stream to control the backlight The module transmits the input voltage to the scan lines of each row, and the control module also generates an image update signal according to the synchronization control signal and the switch signal corresponding to the scan line of the last row, and the image update signal is related to image updating of the display module; and a driving module electrically connected to the backlight module and the display module, and electrically connected to the control module to receive the synchronization control signal and the image stream and the image an update signal, the drive module also generates an output signal to the display module according to the image update signal and the image stream to drive the display module to display and update images, so that the display module follows The image update signal changes to update the displayed image. The driving device of claim 6, wherein the driving module comprises: a storage unit electrically connected to the control module to receive the image stream and temporarily store the image stream, a first driving signal generator electrically connected to a plurality of data lines of the backlight module, the control module and the storage unit to receive the image update signal from the control module and the image from the storage unit an image stream, and generates a plurality of driving signals to the plurality of data lines of the light-emitting diode array according to the image update signal and the image stream, and also generates an update signal according to the image update signal, and A second driving signal generator is electrically connected to the first driving signal generator to receive the update signal, and generate the output signal according to the update signal and the image stream. A scanning type display, comprising: an LED direct display module, receiving an input voltage and including a light emitting diode array with a common anode structure, the light emitting diode array includes a plurality of scanning lines, which are arranged along a row direction with each other , a plurality of data lines are arranged perpendicular to the scan lines along a column direction, a plurality of light emitting diodes are respectively correspondingly arranged between the matrix defined by the plurality of scan lines and the plurality of data lines, each The light emitting diode has an anode electrically connected to the corresponding scan line, and a cathode electrically connected to the corresponding data line; a driving device includes: a control module, which generates an image stream, and a a synchronization control signal, and according to the synchronization control signal and the image stream, a plurality of switching signals corresponding to the plurality of scan lines are generated to the LED direct display module to control the LED direct display module group transmits this input voltage to Each row of scan lines scans the LED direct display module, and the control module also generates an image update signal according to the synchronization control signal and the switching signal corresponding to the scan line of the last row; and a a drive module, electrically connected to the LED direct display module, and electrically connected to the control module to receive the synchronization control signal, the image stream and the image update signal, the drive module is also based on the diagram Like the update signal and the image stream, a plurality of driving signals are respectively generated to the plurality of data lines of the LED direct display module. The scanning display of claim 8, wherein the LED direct display module comprises: a scanning unit that receives a plurality of switching signals and the input voltage and is electrically connected to each scan of the LED array line, and is controlled by the plurality of switching signals to sequentially output the input voltage to the scan lines of each row of the light emitting diode array. The scanning display of claim 8, wherein the driving module comprises: a storage unit electrically connected to the control module to temporarily store the image stream; and a first driving signal generator electrically connected to the The plurality of data lines of the backlight module, the control module and the storage unit receive the image update signal from the control module, the image stream from the storage unit, and update according to the image The signal and the image stream generate a plurality of driving signals to the plurality of data lines of the light emitting diode array. A driving device of a scanning type display, the scanning type display comprises a light-emitting diode direct display module, the light-emitting diode direct-display module receives an input voltage and comprises a light-emitting diode array with a common anode structure, the driving The device includes: a control module, which generates an image stream and a synchronization control signal, and generates a plurality of switching signals corresponding to the plurality of scanning lines to the light-emitting two according to the synchronization control signal and the image stream. The polar body direct display module is used to control the LED direct display module to transmit the input voltage to the scan lines of each row, and the control module is also based on the synchronization control signal and the switching of the scan lines corresponding to the last row signal to generate an image update signal; and a drive module electrically connected to the LED direct display module and electrically connected to the control module to receive the synchronization control signal and the image stream and the image For the update signal, the driving module further generates a plurality of driving signals to the data lines of the LED direct display module according to the image update signal and the image stream.

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