JP2009181139A - Flat panel display device and driving method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat panel display device capable of easily performing adjustment or the like of display characteristics without an additional option board, and to provide a driving method of the flat panel display device. <P>SOLUTION: The flat panel display device comprises: a memory part which stores display characteristic information suited for a related flat panel; a timing controller which receives various kinds of display signals adjusted based on the display characteristic information via a serial bus and outputs a driving signal; a data driver which outputs an image signal to a data line based on the driving signal; and a scan driver which outputs a control signal to a gate line based on the driving signal, wherein the display characteristic information presents at least one of operation frequency including vertical frequency, horizontal frequency and main frequency of image information, gamma value, flicker voltage, brightness, FRC information and I/O format. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a flat panel display device and a driving method thereof, and more particularly to a driving device for driving a flat panel display device and a driving method thereof.

Typical commercial flat panel display devices include a liquid crystal display (LCD) and a plasma display panel (PDP), as well as an EL (Electro Luminescence) display device. Development is underway.
A flat panel display module is usually composed of a flat panel in which cells are arranged in a matrix form between two glass substrates, a PCB module for driving the flat panel, and a case for protecting and integrating them. The

  On the other hand, as shown in the entire circuit configuration diagram of the normal flat panel display module shown in FIG. 1, the PCB module for driving the normal flat panel 40 has the following configuration. Receives R, G, B video data and synchronization signals from outside such as a PC and processes them with a timing controller (T-con: Timing-controller), which is a custom integrated circuit (FPGA) integrated circuit (FPGA). Then, the main PCB 10 that processes and generates video data and various control signals to match the structure of the flat panel 40, the low driver control signal 50 received from the main PCB 10, and the power supply 51 supply the scanning signal to the low signal line. The row driver 20 and the column driver 30 that receives the video data processed by the main PCB 10 and receives the data control signal 60 and the gradation voltage 61 to the flat panel 40 are included.

  However, the conventional driving circuit embodied on the main PCB 10 has a masking timing setting method in which the timing and various input driving interface conditions are limited to specifications set to match the panel. Therefore, it is impossible to modify and modify in a timing and drive manner according to changes in user conditions, display sources, and monitor product input conditions. In other words, even if it is within the driveable range, unless the drive device performs hardware option processing, it is impossible to fluidly optimize display characteristics because the setting is fixed. This is because the input condition of the flat panel display basically has an input timing condition according to the VESA specification, while the graphic source side is a DDC (Digital) stored in the flat panel display module. Data Communication) Generates and displays a digital interface timing control signal for panel driving based on information. In addition, the gamma voltage and various power sources for the gradation classification are set in the flat panel display monitor products that are announced on the market.

  According to the conventional technology, by adding an option board, the user can adjust while checking the screen display status by the OSD (On Screen Display) function, or directly adjust the hardware, etc., gamma, flicker voltage, brightness, scaling, It is possible to adjust FRC (Frame Rate Control), I / O format, and the like. However, according to these functions alone, the optimal screen should be changed by changing the I / O (Input / Output) timing (changing the drive frequency or changing to the minimum blanking time) on the flat panel drive circuit. By driving the standard signal through an additional circuit in the graphic source, it is possible to change the driving frequency or change to the minimum optimal blanking time as described above under the optimum conditions. Even if the driving environment is very good, the I / O format must satisfy a general-purpose display standard. Therefore, no matter how good the conditions are, the risk of change must be very large.

  Especially for monitors, an interface is required to drive different display source I / O formats. If there is a difference in the frame frequency or the number of blanking intervals, an additional system board (A / D board or D / D board etc.) support by option board is necessary. At this time, I / O format is limited in flat panel displays, and the efficiency of display products cannot be used 100%. The jitter due to the option board and the interface conditions between the two do not match well. It can not contribute enough to optimize the characteristics of monitor products.

  As described above, the fixability in the flat panel display occurs because the display method is different from that of the CRT (Cathode Ray Tube) display. In the case of the CRT, the frame frequency is very high from 40 Hz to 85 Hz. Although it can be driven widely, the driving method of the flat panel display is fixed by the characteristics of the panel. That is, if the frame frequency is optimized for the current panel characteristics at 60 Hz, the driving conditions are naturally optimized under the condition of 60 Hz. In addition, since not all graphic cards or display sources conform to the VESA standard, deviations are generated little by little depending on the vendor, and data slightly different from the standard timing is supplied. Therefore, the optimal drive condition timing of the flat panel may be different from the VESA standard signal. In addition, when the standard signal is slightly changed by the supplier, an additional option board is used to adjust the fluid timing in this way, but that alone does not function sufficiently as mentioned above. It can be said that the cost is very large.

  The reference of the Besa display input timing is the blanking time (horizontal synchronization signal, back porch, front porch) to return to the next line after scanning the electron beam line with the CRT standard and 1 The blanking time (vertical synchronization signal, back porch, front porch) required to return to the beginning again at the last position where the frame is scanned is specified for each frame frequency. However, since the driving of the flat panel uses a method such as an active matrix method instead of a scanning method, the time required for retrace after the transmission of the last display signal of a line or frame differs from the CRT, so that the minimum pixel ( The blanking time only needs to be on the order of horizontal return) or line (vertical return). Also, by using an optional board such as an A / D board, the operating frequency increases due to unnecessary blanking time under VESA conditions, and the blanking time becomes long and unstable, so interface processes and I / O If becomes unstable, the driving condition of the flat panel becomes very unstable. Therefore, as described above, it is necessary to reduce the blanking time so that the flat panel can be driven under the optimum driving timing conditions, to stabilize the display characteristics and improve the reliability.

  Also, the display characteristics may have to be adjusted differently depending on the product deviation or the user's environment and conditions. In the case of such a flat panel monitor product, it has conventionally been necessary to adjust by an additional option board or interface board having an optimum driving condition fixed to match the characteristics of the flat panel. However, if you change the optimal driving conditions fixed to match the characteristics of the flat panel by adjusting the gamma, contrast, bright, flicker, and other display characteristics, if you use an A / D board or option board, There is a problem in that the upper and lower gray levels contrasted by the clapping are interrupted, and the flat panel characteristics cannot be used with 100% efficiency.

  Therefore, it is natural to eliminate the increase in cost due to the use of an option board as described above, and a fundamental driving method that suppresses the occurrence of jitter due to mismatched interface conditions is required. became. In other words, not only the resolution information and information on the operating frequency such as the vertical frequency, horizontal frequency of the video signal, and the main frequency of the video signal, but also digital information on the gamma, flicker voltage, luminance value, etc. that can be adjusted by the user. A need has arisen for flexible changes to FRC, I / O format, other display characteristics information, etc. so that it can be shared between graphic sources and flat panel display modules and updated by the user. In particular, even if the signal output from the graphic source is a video signal that has been changed to the frequency of the video signal by changing the blanking time as defined by the user in addition to the standard signal, it is basically a flat panel. It is necessary to be able to make maximum use so as to be suitable for driving the display device.

  Therefore, the object of the present invention is to save and share I / O timing and other display characteristics in the driving device by using a serial bus having a VESA standard DDC function without an additional option board. An object of the present invention is to provide a flat panel display device having a wide and flexible interface that enables adjustment and uploading, and a driving method thereof.

A flat panel display device according to one aspect of the present invention for achieving such a technical problem includes a memory unit that preliminarily stores display characteristic information suitable for a corresponding flat panel, and the memory unit. A timing controller that receives various display signals adjusted by a graphic source based on display characteristic information stored in the serial bus and outputs a drive signal based on the various display signals, and a drive received from the timing controller A data driver that outputs a video signal to the data line based on the signal;
And a scan driver that outputs a control signal to a gate line based on a drive signal received from the timing controller, wherein the display characteristic information includes a vertical frequency, a horizontal frequency, and a main frequency of video information. It includes at least one of operating frequency, gamma value, flicker voltage, luminance, FRC information, and I / O format.

Here, the memory unit may be a non-volatile memory.
The display characteristic information can be changed by a predetermined signal output from the graphic source to the serial bus according to predetermined data input by a user using a predetermined program. .
Further, the display characteristic information can be changed by a user inputting predetermined data using a predetermined key installed outside the flat panel display device.

  The driving method of the flat panel display device of the present invention is based on the step of preliminarily storing display characteristic information suitable for the corresponding flat panel in the memory unit and the display characteristic information stored in the memory unit. Receiving various display signals adjusted by the graphic source through the serial bus, and extracting display characteristic information suitable for the corresponding flat panel from the memory unit based on the various display signals received from the graphic source. Outputting a drive signal based on the extracted display characteristic information; outputting a video signal to a data line based on the drive signal; and outputting a control signal to a gate line based on the drive signal And the display characteristic information is a drop of the video information. Frequency, operating frequency, gamma value including horizontal frequency, and the main frequency, flicker voltage, brightness, FRC information, as well, characterized in that they exhibit at least one of the I / O format.

In driving a flat panel display device according to the present invention, it is natural to eliminate an increase in cost and the like due to the use of an option board. it can.
Further, the display graphic card or the display source reads the I / O format information from the serial bus or I ² C bus of the interface cable connector such as DVI or D-SUB, and reads the driving conditions of the flat panel to obtain the I / O interface. Search for the optimal conditions to be set, specify the I / O timing required by the user or the display source, and send the setting value to the flat panel again under the optimal conditions, and set the display timing required by the display source. By being able to do so, the graphic signal can be supported under any standard timing conditions other than VESA. In particular, when the same display resolution and the same frame frequency, the flat panel drive frequency can be driven even at a frequency lower than the VESA standard. If the frequency is lowered, the charging time for pixel display, etc. due to the characteristics of the flat panel This has the effect of improving the display characteristics due to a longer time and a time margin for pixel data processing.

In addition, when the optimum driving condition timing of the flat panel is different from the VESA standard signal or the standard signal is slightly deviated by the contractor, the fluid timing is changed to the timing controller serial bus (I ² C bus, SPI The input timing and output timing can be freely adjusted by an interface (such as a bus or 3-WIRE bus). Then, the data setting value is stored in a memory for storing DDC (Digital Data Communication) display information so that timing information can be shared, accurate information on I / O can be stored, continuous update, Control of DDC display information by changing driving conditions without additional optional system (A / D board with scaler, DSP, FRC function, etc.) by enabling continuous adjustment to changes in external environment It becomes possible to secure a wide range of characteristics with respect to the timing margin of the monitor product.

  Of the display characteristics, gamma generates a voltage externally fixed by a resistance or voltage division method, and the gamma is fixed to a target value. For this reason, if contrast or brightness is adjusted using an A / D board or other intermediate interface, gamma adjustment for the entire gradation cannot be performed, but the voltage can be freely set by the serial bus and the monitor product The gradation characteristic level can be adjusted to a desired value without change, and adjustment can be performed while using 100% of the luminance efficiency of the flat panel.

  In addition, the values adjusted by the user and the values set according to the requirements of the graphic source can be stored in a storage device such as a memory shared via the serial bus, and can be adjusted by sharing the status and information of the monitor product. In addition, it is possible to update / re-input and manage the optimum display characteristic information.

It is a block diagram for demonstrating the whole structure of a normal flat panel display module. FIG. 3 is a block diagram illustrating a graphic source unit and a flat panel display module according to an embodiment of the present invention. It is an example of the display signal which generate | occur | produces in a graphic source part by the prior art. 4 is an example of a display signal generated in a graphic source unit according to an embodiment of the present invention. 6 is a diagram illustrating a gamma change when an option board is used according to a conventional technique. 4 is a diagram illustrating a gamma change when adjusting display characteristics through a serial bus according to an exemplary embodiment of the present invention.

Hereinafter, a specific configuration and operation of a flat panel display device according to a preferred embodiment in which a person having ordinary knowledge in the technical field of the present invention can easily implement the present invention will be described in detail with reference to the accompanying drawings. .
As shown in FIG. 2, the basic configuration of the liquid crystal display device (flat panel display device) according to the embodiment of the present invention includes a graphic source 300 including a graphic source unit 310, a connector 410, a D / A conversion unit 420, and a memory unit 430. And a liquid crystal panel display module 400 including a timing control unit 440. Here, in the liquid crystal display device according to the embodiment of the present invention, all the functions of the conventional option board can be realized, and even if the option board is removed, the functions beyond that are maintained, resulting in cost reduction. Contribute. Further, it is not necessary to use an option board as in the conventional configuration, but even when this is adopted, there is no problem in realizing all functions according to the features of the present invention.

  The graphic source unit 310 corresponds to a system that outputs a PC main body or other video signals, that is, a device that generates and outputs a synchronization signal, a graphic signal, and other control signals as a part of the graphic source 300. In particular, the display characteristic information of a liquid crystal panel (flat panel) used for the liquid crystal panel display module is read and interpreted through a serial bus, thereby outputting a display signal of a new corresponding standard.

The connector 410 is a serial bus connector such as DVI or D-SUB for receiving a display signal output from the graphic source unit 310 of the graphic source 300 such as a PC main body and transmitted through predetermined cables 311 and 312.
The D / A converter 420 converts predetermined screen display information included in the display characteristic information of the liquid crystal panel stored in the memory unit 430 into an analog signal. In other words, screen display information such as gamma, flicker voltage, and brightness that must be supplied as an analog voltage after D / A conversion in the display characteristic information of the liquid crystal panel that can be adjusted by the user, Received as a data value, converted to an analog voltage, and supplied to each corresponding circuit of the PCB module. Here, the series of operations as described above are executed under the control of the timing control unit 440 in the same manner as the operation of a general liquid crystal display device.

  The memory unit 430 stores flat panel display characteristic information that can be changed by the user, and is shared with the graphic source unit 310. Here, the display characteristic information of the liquid crystal panel is information relating to the standard of the liquid crystal panel, such as resolution information for driving the liquid crystal panel, operating frequency information such as the vertical frequency, horizontal frequency of the video signal, and the main frequency of the video signal. As well as digital information related to gamma, flicker voltage, luminance value, etc. that can be adjusted by the user. The memory unit for storing information as described above may be a non-volatile memory represented by a user-writable PROM, a rewritable EPROM, or the like.

  The timing control unit 440 receives a display signal output from the graphic source unit 310 through the serial bus, performs arithmetic processing, and outputs a display signal for driving the liquid crystal panel. That is, a display signal of the liquid crystal panel such as a video signal and a control signal corresponding to the display characteristic information of the liquid crystal panel is output and supplied to each corresponding circuit of the PCB module.

The operation of the liquid crystal display device according to the embodiment of the present invention having such a structure will be described in more detail.
First, in the case of CRT, the frame frequency can be driven very widely from 40 Hz to 85 Hz, but unlike this, the driving method of the liquid crystal panel display is fixed by the characteristics of the panel, so the frame frequency However, if the current panel characteristics are optimized at 60 Hz, the driving conditions such as the timing control unit 440 are naturally optimized under the 60 Hz condition. However, the general monitor display so far receives the signal output from the graphic source 300 fixed to a standard signal such as VESA by the liquid crystal panel display module 400, and the arithmetic processing of the option board and the timing controller However, it is possible to adjust the FRC and I / O formats to some extent and output them, but there is no case in which the signals output from the graphic source 300 are adjusted so that the FRC and I / O formats are adjusted. In particular, the long blanking time is necessary only for the scanning method of the CRT, and is not necessary for the display such as the active matrix method using the digital signal processing such as the liquid crystal panel display. This is advantageous in driving the liquid crystal panel.

Accordingly, in the liquid crystal display device according to the embodiment of the present invention, not only the FRC and I / O format of the signal itself output from the graphic source 300 but also the blanking time can be adjusted without using the option board. The operation process is as follows.
The operation of the liquid crystal display according to the embodiment of the present invention as shown in FIG. 2 is as follows. First, a liquid crystal panel display module (or monitor) 400 connected to a predetermined cable 311 or 312 through a graphic source 300 such as a PC main body and a DVI or D-SUB connector 410 is installed for the entire operation. The display characteristic information of the liquid crystal panel stored in the memory unit 430 is transmitted to the graphic source unit 310 through the serial buses 411 and 412 as DDC information. The graphic source unit 310 interprets such information and transmits various display signals corresponding to the interpretation result to the liquid crystal panel display module 400 through predetermined cables 311 and 312.

  At this time, unlike the conventional technique, the display characteristic information of the liquid crystal panel is included in the shared DDC information between the graphic source unit 310 and the memory unit 430 of the liquid crystal panel display module 400. At this time, the display characteristic information of such a liquid crystal panel can be changed by a user by a predetermined application program or the like, and the information thus changed is updated again in the memory unit 430, and such a liquid crystal display device is obtained. Is used again, the graphic source unit 310 reads and interprets it according to the information updated in the memory unit 430. In other words, the user can directly adjust the input timing at the graphic source unit (PC or other display system) 310 by re-inputting the optimum conditions suitable for the liquid crystal panel to the graphic source 300 (recommand). It has become.

  Here, the display characteristics information of the liquid crystal panel that can be changed by the user by a predetermined application program, etc. includes screen display (luminance, gamma, flicker, etc.) that appears on the screen in addition to the FRC and I / O formats as described above. There is information. In particular, the blanking time existing in the standard video signal can be adjusted, and the liquid crystal display module 400 operates by receiving a signal of a new standard different from the VESA standard signal.

  That is, as shown in FIG. 3, the conventional display signal generated by the graphic source unit 310 includes a synchronization signal portion (a), a back porch (b), a portion (c) on which video data is placed, and a front porch (d ), And the back porch (b) is slightly longer than the front porch (d). On the other hand, if the blanking time is adjusted according to the embodiment of the present invention, as shown in FIG. 4, the portion (g) on which the video data is placed becomes relatively long, and the other sync signal portion (e), The back porch (f), the front porch (h), and the like remain only as necessary for signal processing for driving the liquid crystal panel and become as narrow as possible. The user adjusts the blanking time by a predetermined application program, for example, because the display signal standard information, that is, the portion (g) where the video data is placed, the synchronization signal portion (e), the back porch ( f), a time for the front porch (h), etc., is defined so that the graphic source unit 310 generates a display signal of a new standard.

  As described above, when new display characteristic information is updated in the memory unit 430, the graphic source unit 310 reads out and interprets this information to generate a display signal corresponding to the information and transmit it to the liquid crystal panel display module 400. . At this time, the transmitted display signal is shared by the D / A converter 420 and the timing controller 440 through the serial buses 411 and 412. The timing control unit 440 generates video signals and various control signals necessary for driving the liquid crystal panel, and supplies them to the corresponding circuits of the PCB module along the wiring 441. The D / A conversion unit 420 is also controlled by the timing control unit 440 based on the display characteristic information stored in the memory unit 430, and D / A converts digital data for states such as gamma, flicker, and luminance to the wiring 421. Along with this, each corresponding circuit of the PCB module is supplied.

  As described above, if the user adjusts the screen display (brightness, gamma, flicker, etc.) data indicating the screen display state by a predetermined application program, an additional option board such as an A / D board is provided. In addition, since the existing OSD function can be realized by digital processing, the gamma value unique to the liquid crystal panel can be used in all areas. In other words, as shown in FIG. 5, when using an option board such as a conventional A / D board, the brightness of the circuit is the highest when adjusting the brightness (A) compared to the reference gamma change (R). When gradation values near the gradation are lost and the contrast is adjusted (B), the gradation values near the lowest gradation are lost. However, as shown in FIG. 6, digital processing is performed according to the embodiment of the present invention. By doing so, even if the brightness is adjusted (C) or the contrast is adjusted (D), the gamma change that is almost close to the reference gamma change (R) is maintained, so that the display capability of the liquid crystal panel can be utilized to the maximum. Can do.

On the other hand, the user can adjust the display characteristic information of the liquid crystal panel indicating the display state of the screen through a predetermined application program or the like, and this also supports the OSD function in all monitors. This can be realized in combination with setting a predetermined key outside the liquid crystal display device and inputting predetermined data to the user.
As described above, according to an embodiment of the present invention, in the liquid crystal display device that receives and processes a display signal output from the graphic source unit 310 through the serial bus, the graphic source unit 310 transmits the liquid crystal panel display module through the serial bus. By reading and interpreting the display characteristic information of the liquid crystal panel at 400, it is possible to output a display signal of a new corresponding standard. Here, the display characteristic information of the liquid crystal panel is obtained by a predetermined signal that a user inputs predetermined data using a predetermined program and outputs to the serial bus in the graphic source unit 310 corresponding to the data. Not only can the change be made, but the change can also be made by the user inputting predetermined data using a predetermined key installed outside the liquid crystal panel display device.

  The description about the liquid crystal display device according to the embodiment of the present invention described above is not limited to the liquid crystal display device, but a plasma display device (PDP) or an organic EL display device having a similar driving method on the PCB module. The present invention can be applied to a general flat panel display device as it is, and various modifications and implementations can be made without departing from the scope of the present invention.

  The present invention can be applied to a liquid crystal display device, a plasma display device, an EL display device, and other various flat panel display devices.

10 Main PCB
20 Low Driver 30 Column Driver 40 Flat Panel 50 Low Driver Control Signal 51 Power Supply 61 Gradation Voltage 300 Graphic Source 310 Graphic Source Unit 311, 312 Cable 400 Liquid Crystal Panel Display Module 410 Serial Bath Connector 411, 412 Serial Bath 420 D / A Conversion unit 430 Memory unit 440 Timing control unit 441 Wiring

Claims (5)

A memory unit that stores display characteristic information suitable for the corresponding flat panel in advance and can be changed;
A timing controller that receives various display signals adjusted by a graphic source based on display characteristic information stored in the memory unit through a serial bus, and outputs a driving signal based on the various display signals;
A data driver that outputs a video signal to a data line based on the drive signal received from the timing controller;
A scan driver that outputs a control signal to the gate line based on the drive signal received from the timing controller;
A flat panel display device including
The display characteristic information includes at least one of an operating frequency including a vertical frequency, a horizontal frequency, and a main frequency of video information, a gamma value, a flicker voltage, luminance, FRC information, and an I / O format. Display device.   The flat panel display device according to claim 1, wherein the memory unit is a nonvolatile memory.   The display characteristic information can be changed by a predetermined signal output from the graphic source to the serial bus in accordance with predetermined data input by a user using a predetermined program. Flat panel display device.   2. The flat panel display according to claim 1, wherein the display characteristic information can be changed by a user inputting predetermined data using a predetermined key installed outside the flat panel display device. apparatus. Preliminarily storing display characteristic information suitable for the corresponding flat panel in the memory unit in a changeable manner,
Receiving various display signals adjusted by a graphic source based on display characteristic information stored in the memory unit through a serial bus;
Extracting display characteristic information suitable for a corresponding flat panel from the memory unit based on various display signals received from the graphic source, and outputting a drive signal based on the extracted display characteristic information;
Outputting a video signal to a data line based on the driving signal;
Outputting a control signal to the gate line based on the driving signal;
A driving method of a flat panel display device including
The display characteristic information includes at least one of an operating frequency including a vertical frequency, a horizontal frequency, and a main frequency of video information, a gamma value, a flicker voltage, luminance, FRC information, and an I / O format. A driving method of a display device.

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