WO2013026227A1 - 液晶显示器的驱动方法及液晶显示器 - Google Patents

液晶显示器的驱动方法及液晶显示器 Download PDF

Info

Publication number
WO2013026227A1
WO2013026227A1 PCT/CN2011/081012 CN2011081012W WO2013026227A1 WO 2013026227 A1 WO2013026227 A1 WO 2013026227A1 CN 2011081012 W CN2011081012 W CN 2011081012W WO 2013026227 A1 WO2013026227 A1 WO 2013026227A1
Authority
WO
WIPO (PCT)
Prior art keywords
liquid crystal
grayscale value
crystal display
value
frame
Prior art date
Application number
PCT/CN2011/081012
Other languages
English (en)
French (fr)
Inventor
贺成明
侯鸿龙
Original Assignee
深圳市华星光电技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=45336402&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=WO2013026227(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by 深圳市华星光电技术有限公司 filed Critical 深圳市华星光电技术有限公司
Priority to US13/375,232 priority Critical patent/US20130044144A1/en
Publication of WO2013026227A1 publication Critical patent/WO2013026227A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G09G3/3611—Control of matrices with row and column drivers
    • G09G3/3648—Control of matrices with row and column drivers using an active matrix
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/0252—Improving the response speed
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2340/00—Aspects of display data processing
    • G09G2340/16—Determination of a pixel data signal depending on the signal applied in the previous frame

Definitions

  • the present invention relates to the field of liquid crystal display, and in particular to a method for driving a liquid crystal display and a liquid crystal display.
  • the overdrive is usually used (Over Driver, OD) technology.
  • Each stable state of the liquid crystal molecules corresponds to a certain voltage.
  • the driving voltage applied to the liquid crystal molecules is the corresponding voltage of the target state. Since the corresponding voltages of different gray scales are different, the angles at which the molecules need to be rotated are also different, which causes response time of different gray scale transitions. Everything varies.
  • the applied driving voltage is slightly higher than the corresponding voltage of the target state at the beginning, so that the liquid crystal molecules rotate faster, and when the target state is reached, the voltage falls back to the target state.
  • the corresponding voltage is maintained, which effectively shortens the reaction time and averages the response time of different gray-scale switching.
  • the overdrive technology accelerates the reaction speed of the liquid crystal by applying an electric field intensity corresponding to the original steady state, so that the liquid crystal can be turned to a predetermined angle in a short time, so that the response time of the liquid crystal can be reduced to 8 ms or less.
  • the liquid crystal molecules are converted from the initial gray level (such as 0 order) to the target gray level (such as 128 steps); the 0th order driving voltage is 0V, and the 128th order driving voltage is 3V, when the liquid crystal display screen is from 0th order to 128th.
  • the step is converted, if the driving voltage is given 0Và3V, the speed at which the liquid crystal molecules rotate is often not fast enough.
  • 0V à 4V can be given to increase the speed (assuming that 4V is the driving voltage of 150 steps), an overdrive lookup table is needed (Lookup) Table, LUT), when converting from 0th order to 128th order, the 150th order overdrive grayscale value can be obtained through the lookup table, and then the original 128th order is replaced by 150th order.
  • FIG. 1 is a schematic diagram showing changes in luminance of liquid crystal molecules in the prior art without OD operation; in the absence of OD operation, the voltage timing is 0 V à 3 V à 3 V, at which time the brightness of the liquid crystal molecules changes slowly.
  • FIG. 2 is a schematic diagram showing the change of the brightness of the liquid crystal molecules when the OD operation is used in the prior art; when the OD operation is used, the voltage timing is 0 V 4 4 V à 3 V, and the brightness of the liquid crystal molecules changes rapidly.
  • FIG. 3 is a schematic diagram of a gray scale comparison in a lookup table of an OD operation in the prior art; During operation, the circuit control will find a suitable next gray level according to the signal change of the pixel of the liquid crystal panel to achieve a faster change speed.
  • the 0-order conversion to the 128-order is taken as an example, and the result of the look-up table is 150 steps corresponding to 128 steps.
  • OD technology has been used in the industry for a long time, but when used on a high update rate liquid crystal panel, since the time of 1 frame (frame) becomes shorter, although the OD operation can give the liquid crystal molecules a driving voltage for a while, due to the liquid crystal molecules The rotation speed cannot keep up, and it is not enough for the liquid crystal molecules to rotate to 90% of the desired brightness for a set length of time, which affects the effect of the OD operation.
  • the above high update rate is defined relative to the existing liquid crystal technology. Under the existing update rate of 60 Hz, the reaction speed of the liquid crystal molecules generally meets the requirements of the OD operation within a set time, so that the display The picture reaches the desired brightness.
  • the frame conversion time becomes shorter, resulting in an OD operation above a certain update rate.
  • the liquid crystal molecules have an increase in the reaction speed under the action of the overdrive voltage, they are limited. The above reaction speed is still not fast enough, and the target of the OD operation cannot be achieved, and the display screen does not reach the desired brightness.
  • the time of 1 frame is approximately 4.15 ms (1/240 second), and when the update rate is 60 Hz, the time of 1 frame is approximately 16.6 ms.
  • the time required for the liquid crystal molecules to perform most of the gray scale conversion is more than 5 ms. Therefore, when the OD operation is performed at 240 Hz, when the liquid crystal molecules have not reached the level, the OD is stopped and returned to the normal driving voltage, and the liquid crystal molecules rotate slowly, resulting in the rotation not being in place, and the OD operation is less than expected. .
  • the voltage timing is 0V à 4V à 3V.
  • 4 is a graph showing changes in brightness of liquid crystal molecules with OD operation over time at an update rate of 60 Hz; at this time, liquid crystal molecules can be rotated into position within a frame time (16.6 ms) to reach 90% of the desired brightness. It can be seen from the figure that in the absence of OD operation, ⁇ t time is required to achieve brightness from 10% to 90%; and in OD operation, brightness from 10% to 90% requires only ⁇ t' time ( ⁇ t' ⁇ ⁇ t).
  • FIG. 5 is a schematic diagram showing changes in luminance of liquid crystal molecules with OD operation with time when the update rate is 240 Hz; for comparison, at an update rate of 60 Hz, when there is OD operation and no OD operation, the curve of brightness of liquid crystal molecules with time is also described.
  • the time length of one frame becomes 1/4 time (16.6ms à 4.15ms) at 60Hz, and within 4.15ms of performing the OD operation, the liquid crystal molecules fail to rotate into place (the rotation time of the 0à128 gray scale is generally greater than 5ms) .
  • the main object of the present invention is to provide a driving method of a liquid crystal display and a liquid crystal display, which improve the display effect of the display.
  • the invention provides a driving method of a liquid crystal display, comprising the steps of:
  • the preset second query table is queried according to the frame information of the previous frame, and the actual grayscale value of the previous frame is obtained;
  • the frame information includes at least a grayscale value
  • Overvoltage driving is performed according to the overdrive gray scale value.
  • the second query table is queried according to the frame information of the previous frame, and the step of obtaining the actual grayscale value of the previous frame further includes:
  • the first lookup table and the second lookup table are established.
  • the first lookup table is an overdrive grayscale value lookup table for grayscale conversion between frames in an overvoltage driving operation; the second lookup table is performed in a liquid crystal display with high update rate A comparison table for correcting the gray scale of liquid crystal molecules during voltage-driven operation.
  • the data of the second lookup table is obtained by pre-testing.
  • the step of performing overvoltage driving according to the overdrive grayscale value further comprises:
  • the overvoltage driving is stopped.
  • the preset value is 5th order.
  • the invention also provides a liquid crystal display, comprising a preset first lookup table and a preset second lookup table; further comprising:
  • a grayscale obtaining unit configured to query a second query table according to frame information of a previous frame to obtain an actual grayscale value of a previous frame when converting from a previous frame to a next frame; the frame information includes at least a grayscale value;
  • An overdrive grayscale value obtaining unit is configured to query the first query table according to the actual grayscale value of the previous frame and the predetermined grayscale value of the next frame, and obtain an overdrive grayscale value for grayscale conversion;
  • An overvoltage driving unit is configured to perform overvoltage driving according to the overdrive grayscale value.
  • the method further comprises:
  • a establishing unit configured to establish the first query table and the second query table.
  • the first lookup table is an overdrive grayscale value lookup table for grayscale conversion between frames in an overvoltage driving operation; the second lookup table is performed in a liquid crystal display with high update rate A comparison table for correcting the gray scale of liquid crystal molecules during voltage-driven operation.
  • the data of the second lookup table is obtained by pre-testing.
  • a comparison unit is further included for:
  • the overvoltage driving is stopped.
  • the preset value is 5th order.
  • the invention also provides a liquid crystal display comprising:
  • a establishing unit configured to establish the first query table and the second query table;
  • the first query table is an overdrive grayscale value query table for grayscale conversion between frames in an overvoltage driving operation;
  • the second look-up table is a comparison table for correcting the gray scale of the liquid crystal molecules when the over-voltage driving operation is performed in the liquid crystal display with high update rate;
  • a grayscale obtaining unit configured to query a second query table according to frame information of a previous frame to obtain an actual grayscale value of a previous frame when converting from a previous frame to a next frame; the frame information includes at least a grayscale value;
  • An overdrive grayscale value obtaining unit is configured to query the first query table according to the actual grayscale value of the previous frame and the predetermined grayscale value of the next frame, and obtain an overdrive grayscale value for grayscale conversion;
  • An overvoltage driving unit is configured to perform overvoltage driving according to the overdrive grayscale value.
  • the data of the second lookup table is obtained by pre-testing.
  • the liquid crystal display further comprises a comparison unit for:
  • the overvoltage driving is stopped.
  • the preset value is 5th order.
  • the driving method of the liquid crystal display of the present invention and the liquid crystal display perform gray scale correction by adding a second lookup table, and compare the corrected actual gray scale value with the preset gray scale value of the next frame, according to the difference between the two
  • the absolute value of the value is selected to perform a conventional voltage driving or overvoltage driving operation to avoid affecting the display effect of the display due to improper operation, thereby improving the display effect of the liquid crystal display.
  • FIG. 1 is a schematic diagram showing changes in luminance of liquid crystal molecules when there is no OD operation in the prior art
  • FIG. 2 is a schematic diagram showing changes in luminance of liquid crystal molecules when OD operation is used in the prior art
  • FIG. 3 is a schematic diagram of a gray scale comparison in a lookup table of an OD operation in the prior art
  • FIG. 4 is a schematic diagram showing changes in brightness of liquid crystal molecules with OD operation at 60 Hz in the prior art
  • FIG. 5 is a schematic diagram showing changes in brightness of liquid crystal molecules with time during OD operation at 240 Hz in the prior art
  • FIG. 6 is a schematic flow chart showing the steps of a first embodiment of a driving method of a liquid crystal display according to the present invention.
  • FIG. 7 is a schematic flow chart showing the steps of a second embodiment of a driving method of a liquid crystal display according to the present invention.
  • FIG. 8 is a schematic diagram of a frame conversion operation of the driving method of the liquid crystal display shown in FIG. 6 and FIG. 7;
  • FIG. 9 is a schematic diagram of querying a preset first lookup table of the driving method of the liquid crystal display shown in FIG. 6 and FIG. 7;
  • FIG. 10 is a schematic diagram of a query of a second query table preset by the driving method of the liquid crystal display shown in FIG. 6 and FIG. 7;
  • FIG. 11 is a flow chart showing the steps of a third embodiment of a driving method of a liquid crystal display according to the present invention.
  • FIG. 12 is a schematic diagram showing the brightness display of a driving method of a liquid crystal display according to the present invention.
  • Figure 13 is a schematic structural view of a first embodiment of a liquid crystal display according to the present invention.
  • Figure 14 is a schematic structural view of a second embodiment of a liquid crystal display according to the present invention.
  • Figure 15 is a schematic view showing the structure of a third embodiment of a liquid crystal display of the present invention.
  • the liquid crystal display may not be effective in changing the existing OD technology, and can be considered from two aspects:
  • the query mode of the query table in the OD operation is that the signal of the previous frame is compared with the latter frame, and the corresponding overdrive gray is obtained after the table is checked.
  • Order value For example, taking 0à128à128 order as an example, the query result is 0à150(+22)à128(+0) +0 means no OD operation.
  • the signal is in the third frame, it should be 128 steps.
  • the actual situation is that the reaction time of the liquid crystal molecules is not enough, which is less than 128 steps. Correcting the inconsistency between the two is The focus of the invention.
  • FIG. 6 is a flow chart showing the steps of a first embodiment of a driving method of a liquid crystal display according to the present invention. Referring to FIG. 6, an embodiment of a driving method of a liquid crystal display according to the present invention is proposed, wherein the method includes:
  • Step S10 When converting from the previous frame to the next frame, querying the preset second query table according to the frame information of the previous frame, and obtaining an actual grayscale value of the previous frame; the frame information includes at least a grayscale value;
  • Step S11 Query a preset first query table according to an actual grayscale value of the previous frame and a predetermined grayscale value of the next frame, and obtain an overdrive grayscale value for grayscale conversion;
  • Step S12 Perform overvoltage driving according to the overdrive grayscale value.
  • the display effect of the liquid crystal display is improved by adding a second look-up table to perform gray scale correction.
  • FIG. 7 is a flow chart showing the steps of a second embodiment of the driving method of the liquid crystal display according to the present invention.
  • the second embodiment is a flow chart of another step based on the first embodiment shown in FIG. 6. Referring to FIG. 7, based on the first embodiment, before step S10, the method further includes:
  • Step S9 Establish the first query table and the second query table.
  • the first lookup table may be an overdrive grayscale value lookup table for grayscale conversion between frames in an OD (overvoltage drive) operation, and the first lookup table may use a prior art overdrive lookup table.
  • the liquid crystal display can query the first query table to find the corresponding overdrive grayscale value by using the grayscale values of the two frames before and after.
  • the second lookup table may be a comparison table for correcting the actual state (grayscale) of the liquid crystal molecules when the OD operation is performed in the liquid crystal display with high update rate.
  • the first query table and the second query table may be established by obtaining relevant data through a preliminary experiment. Different types of liquid crystal displays and liquid crystal display panels are different according to specific parameters (such as update rate), and usually have different first queries. Table and second query table. This high update rate can be an update rate above 60 Hz.
  • FIG. 8 is a schematic diagram of a frame conversion operation of the driving method of the liquid crystal display shown in FIGS. 6 and 7.
  • first Querying the first query table to obtain the driven grayscale value to perform the first OD operation after performing the first OD operation, querying the second query table according to the target grayscale value of the Nth frame in the first OD operation Obtaining the actual grayscale value of the frame after the first OD operation to form new frame information (image); and when converting from the second frame to the third frame (the N+1th frame), according to the Nth
  • the actual grayscale value of the frame and the target grayscale value of the (N+1)th frame query the first query table to obtain the required overdrive grayscale value, and perform the second OD operation. Then and so on.
  • FIG. 9 and FIG. 10 are schematic diagrams of a preset first lookup table and a preset second lookup table of the driving method of the liquid crystal display device shown in FIG. 6 and FIG. 7, respectively.
  • the gray level (frame) conversion is 0 à 128 à 128 à 128.
  • the OD operation is: 0 à 150 à 128 à 128, the corresponding liquid crystal state is: 0 à 128 à 128 (the liquid crystal is rotated into position); when the update rate is 240 Hz, the OD operation is performed. :0à150à128à128, but in the case of no correction, the actual state of the liquid crystal is: 0à100à115à128, the effect of the OD operation is not ideal, and the display screen does not reach the predetermined brightness.
  • the driving method of the liquid crystal display of the present invention corrects the grayscale value corresponding to the liquid crystal state after the OD operation by the second lookup table, obtains an appropriate overdrive grayscale value, and corrects the next OD operation to make the liquid crystal tend to be in an ideal state.
  • querying the first lookup table indicates that the OD operation requires 150-order overdrive grayscale value (greater than 128th order), but the OD operation time of one frame is short (4.15ms). ), so the liquid crystal does not reach the 128th order of the preset brightness in the next frame, assuming that there is only 100 steps (the specific value can be determined experimentally), but the system still has a liquid crystal state of 128 steps.
  • the next frame is 128 steps.
  • the first query table is first queried during the OD operation. Since the 128-order conversion is to 128-order, the system will obtain the 128-order overdrive grayscale value, and no OD operation is performed.
  • the actual situation of the liquid crystal state after the OD operation is performed is corrected by querying the second lookup table and according to the actual situation of the previous OD operation, for example, Querying the second lookup table can obtain that the actual state of the liquid crystal after the previous OD operation is only 100 steps, and there is a larger distance from the target value of the OD operation of the 128th order. Therefore, the driving method of the liquid crystal display of the present invention has the preset brightness.
  • the 128-order correction is performed to the actual 100-order, and then the first query table is queried, and the corresponding overdrive grayscale value of the 100th-order conversion to the 128th order is 130th order, and the overdrive grayscale value is obtained for the OD of the next frame.
  • the actual liquid crystal state obtained after the next frame OD operation is known to be 115 steps by the second lookup table, and the first query table is further searched to obtain the overdrive grayscale value of 115 à 128 for the next OD operation, so that the first The second lookup table corrects the deviation caused by the OD operation of the high update rate liquid crystal panel, and improves the effect of the OD operation.
  • FIG. 11 is a flow chart showing the steps of a third embodiment of a driving method of a liquid crystal display according to the present invention.
  • the third embodiment is a flow chart of still another step based on the second embodiment shown in FIG. Referring to FIG. 11, compared with the second embodiment, before step S12, the method further includes:
  • Step S13 Comparing the actual grayscale value with a preset grayscale value of the next frame to obtain a difference between the two;
  • Step S14 determining whether the absolute value of the difference is less than or equal to a preset value; if yes, proceeding to step S15; otherwise, proceeding to step S11;
  • step S15 the overvoltage driving is stopped.
  • the gray-scale conversion if the two gray-scale values of the conversion are too close, if the OD operation is performed, the tone of the gray-scale may be suddenly discontinued, so the gray-scale value is performed in the second query table. After the correction, the corrected actual grayscale value can be compared with the preset grayscale value of the next frame. If the absolute value of the difference between the two is less than or equal to the preset value (for example, less than or equal to 5 steps), the execution is performed.
  • the conventional drive can be used without overvoltage driving to avoid affecting the display of the display.
  • the grayscale correction is performed by the second lookup table, and in addition to improving the driving effect, the function of removing the signal error is also provided.
  • 160à0à160à0 as an example, at the update rate of 240Hz, it can be seen from the first look-up table that 160k0 will be driven by the 0-order overdrive grayscale value, but because the reaction time is not enough, the liquid crystal state is not in place, assuming only 40th order ( 160à40); If not corrected by the second lookup table, according to the existing OD operation, the system default LCD has reached 0 order, then the first query table will find the overdrive ash from the 0à160 will be given 200 steps The order value is driven; since the actual state is 40 à 160, the overdrive gray scale value only needs to be set to 180 steps.
  • Fig. 12 is a view showing the brightness display of the driving method of the liquid crystal display corresponding to the above example given the erroneous overdrive gray scale value. Referring to FIG. 12, the liquid crystal molecules perform gray scale switching of 160 à 0 à 160.
  • the given overdrive gray scale value is excessive at 0 à 160, the actual state of the liquid crystal molecules after the OD operation has exceeded 160 steps, causing the image brightness to become brighter than expected. Reflected on the display image, for example, a 160-order line moving on a black background will become a brighter line than the 160th order.
  • Figure 13 is a schematic view showing the structure of a first embodiment of a liquid crystal display of the present invention.
  • the liquid crystal display includes a preset first lookup table and a preset second lookup table; and further includes a grayscale acquiring unit and an overdrive grayscale value acquisition.
  • the gray level obtaining unit is configured to query the second query table according to the frame information of the previous frame to obtain the actual grayscale value of the previous frame when converting from the previous frame to the next frame;
  • the frame information includes at least a grayscale value;
  • the overdrive grayscale value obtaining unit is configured to query the first query table according to the actual grayscale value of the previous frame and the predetermined grayscale value of the next frame to obtain a grayscale conversion The required overdrive gray scale value;
  • the overvoltage drive unit is configured to perform overvoltage driving according to the overdrive gray scale value.
  • the gray scale correction is performed by adding the second look-up table, thereby improving the display effect of the liquid crystal display.
  • Figure 14 is a schematic view showing the structure of a second embodiment of a liquid crystal display according to the present invention, which is another structural diagram based on the first embodiment of the liquid crystal display shown in Figure 13.
  • the liquid crystal display of the embodiment may further include: an establishing unit, configured to establish the first query table and the second query table.
  • the first lookup table may be an overdrive grayscale value (OD value) lookup table for grayscale conversion between frames in an OD (overvoltage driving) operation, and the first lookup table may be overdriven by the prior art.
  • OD value overdrive grayscale value
  • the liquid crystal display uses the overdrive grayscale value acquisition unit to query the first query table to find the overdrive grayscale value required to perform the OD operation by using the grayscale values of the two frames before and after.
  • the second lookup table may be a comparison table for correcting the actual state (gray scale) of the liquid crystal molecules when the OD operation is performed in the high update rate liquid crystal display, and the liquid crystal display may use the gray scale acquiring unit from the second lookup table. Get the corrected grayscale value.
  • the first query table and the second query table may be obtained by using a preliminary experiment to obtain corresponding data by using the above-mentioned establishing unit. Different liquid crystal display panels and different high update rates may set respective first query tables and second query tables.
  • the Nth frame when converting from the first frame (N-1th frame) to the second frame (Nth frame), the Nth frame is received and extracted from the memory (Memory). After comparing the N-1 frames, first query the first query table to obtain the corresponding overdrive grayscale value for the first OD operation; after performing the first OD operation, perform the first OD operation according to the Nth frame.
  • the target gray scale value query second query table obtains the actual gray scale value to form new frame information (image); when converting from the second frame to the third frame (the N+1th frame), according to the Nth
  • the actual grayscale value of the frame and the target grayscale value of the N+1th frame query the first query table to obtain a corresponding overdrive grayscale value, and perform a second OD operation. Then and so on.
  • the gray level (frame) conversion is exemplified by 0 à 128 à 128 à 128.
  • the OD operation is: 0 à 150 à 128 à 128, and the corresponding liquid crystal state is: 0 à 128 à 128 (the liquid crystal is rotated in place);
  • the OD operation is: 0 à 150 à 128 à 128, but in the case where no correction is made, the actual state of the liquid crystal is: 0 à 100 à 115 à 128, the effect of the OD operation is not satisfactory, and the display screen does not reach a predetermined brightness.
  • the liquid crystal display of the present invention corrects the grayscale value corresponding to the liquid crystal state after the OD operation by using the second lookup table, obtains an appropriate overdrive grayscale value, and corrects the next OD operation, so that the liquid crystal state tends to an ideal state.
  • the above update rate is from 0th order to 128th order at 240Hz.
  • Querying the preset first lookup table indicates that the OD operation requires 150-order overdrive grayscale value (greater than 128th order), but the OD operation time of one frame is short. (4.15ms), so the liquid crystal does not reach the 128th order of the preset brightness in the next frame, assuming that there is only 100 steps (the specific value can be determined experimentally), but the system still has a liquid crystal state of 128 steps. The next frame is 128 steps.
  • the preset first lookup table is first queried.
  • the system Since the 128th order is converted to the 128th order, the system will obtain the 128th order overdrive grayscale value, and no OD operation is performed. .
  • it is necessary to correct the actual situation of the liquid crystal state after the OD operation by querying the preset second lookup table and according to the actual situation of the previous OD operation. For example, by querying the preset second lookup table, the actual state of the liquid crystal after the previous OD operation is only 100 steps, and the OD operation target value of the 128th order has a larger distance.
  • the liquid crystal display of the present invention needs to The 128-order correction of the preset brightness is corrected to the actual 100-order, and then the preset first look-up table is queried, and the corresponding over-drive gray-scale value of the 100-th order conversion to the 128th order is searched for 130 steps, and the overdrive gray-scale value is obtained.
  • the OD operation of the next frame is performed, and the actual liquid crystal state obtained after the OD operation of the next frame is known to be 115 steps by the second lookup table, and the preset first query table is further searched to obtain the overdrive grayscale value of 115 à 128.
  • the OD operation is performed in the next step, so that the deviation of the OD operation performed by the high update rate liquid crystal panel is corrected by using the preset second lookup table, and the effect of the OD operation is improved.
  • Figure 15 is a schematic view showing the structure of a liquid crystal display according to a third embodiment of the present invention, which is based on a second embodiment of the liquid crystal display shown in Figure 14.
  • the liquid crystal display of the embodiment further includes a comparing unit, configured to: compare the actual grayscale value with a preset grayscale value of a next frame to obtain a difference between the two; and determine an absolute value of the difference. Whether the value is less than or equal to the preset value; when less than or equal to the preset value, the overvoltage driving is stopped.
  • the liquid crystal display can use the comparison unit to compare the corrected actual grayscale value with the preset grayscale value of the next frame, if the absolute value of the difference is less than or equal to a preset value (for example, less than or equal to 5) Order), only need to perform regular voltage drive, no need to carry out overvoltage driving operation, to avoid affecting the display of the display.
  • a preset value for example, less than or equal to 5 Order
  • the grayscale correction is performed by the preset second lookup table, and in addition to improving the driving effect, the function of removing the signal error is also provided.
  • 160à0à160à0 as an example, at the update rate of 240Hz, it can be known from the first look-up table that 160:0 will be driven by the 0-order overdrive grayscale value, but the overdrive time is not enough, the liquid crystal state is not in place, assuming only 40 Step (160à40); if the preset second query table is not corrected, according to the existing OD operation, the system default LCD has reached 0th order, and then it will be found in the preset first query table from 0à160.
  • the overdrive grayscale value Given the 200-order overdrive grayscale value to drive; since the actual state is 40à160, the overdrive grayscale value only needs to be set to 180th order, given the 200th order overdrive grayscale value will make the signal strength too strong, display The edge of the moving target is prone to produce bright and dark sides. If the second query table is modified by the preset second query table, the change of the next frame can be obtained by the preset second query table, and should not be 0 à 160, but 40 à 160; and then through the preset first lookup table, It can be found that a reasonable overdrive grayscale value is 180 steps, which can correct signal errors and perform reasonable OD operations. FIG.
  • FIG. 12 is a schematic diagram showing the brightness display of the driving method of the liquid crystal display corresponding to the above example given the error overdrive gray scale value.
  • the liquid crystal molecules perform gray scale switching of 160 à 0 à 160. Since the given overdrive gray scale value is excessive at 0 à 160, the actual state of the liquid crystal molecules after the OD operation has exceeded 160 steps, causing the image brightness to become brighter than expected. Reflected on the display image, for example, a 160-order line moving on a black background will become a brighter line than the 160th order.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
  • Liquid Crystal (AREA)

Abstract

一种液晶显示器的驱动方法及液晶显示器，该方法包括：当从上一帧向下一帧转换时，根据上一帧的帧信息查询预设的第二查询表（32），取得上一帧的实际灰阶值（S10）；所述帧信息至少包括灰阶值；根据上一帧的实际灰阶值以及下一帧的预定灰阶值查询预设的第一查询表（31），获取用于灰阶转换的过驱动灰阶值（S11）；根据所述过驱动灰阶值进行过电压驱动（S12）。本发明通过增加设置第二查询表进行灰阶修正，提升了液晶显示器的显示效果。

Description

液晶显示器的驱动方法及液晶显示器
技术领域
本发明涉及到液晶显示领域，特别涉及到一种液晶显示器的驱动方法及液晶显示器。
背景技术
现有技术的液晶显示器中为解决残影现象，通常使用过驱动（Over Driver，OD）技术。液晶分子每一种稳定的状态都对应着一定的电压，当在电极上加电压时，液晶分子不是即时转动到目标状态，而是在一定的响应时间之后才能达到这个状态，电压越高，分子转动的速度越快。传统的液晶显示器中，在液晶分子上施加的驱动电压就是目标状态的对应电压，由于不同灰阶的对应电压不同，分子需要转过的角度也不同，这就造成了不同灰阶转换的响应时间千差万别。而在采用过驱动技术的液晶显示器中，施加的驱动电压在起始的时候稍高于目标状态的对应电压，使得液晶分子转动的速度更快，在到达目标状态时，电压再回落至目标状态的对应电压以保持状态，这样就有效缩短了反应时间，而且使不同灰阶切换的响应时间平均化。
该过驱动技术通过施加高于原本稳态时所对应的电场强度，加快液晶的反应速度，使液晶能在较短时间内转到预定角度，使液晶的响应时间能够降低到8ms或更短。例如：将液晶分子从起始灰阶（如0阶）转换成目标灰阶（如128阶）；设0阶驱动电压为0V，128阶驱动电压为3V，当液晶显示器画面从0阶到128阶作转换时，若驱动电压给定0Và3V此时液晶分子转动的速度往往不够快，通常可以给0Và4V以增快速度（假定4V是150阶的驱动电压），就需要一个过驱动查询表（Lookup Table，LUT），使得从0阶转换到128阶时，可通过该查询表得到150阶的过驱动灰阶值，然后以150阶取代原本的128阶进行过驱动操作。
图1是现有技术中没有OD操作时的液晶分子亮度变化示意图；在没有OD操作时，该电压时序为0Và3Và3V，此时液晶分子亮度变化慢。
图2是现有技术中使用OD操作时的液晶分子亮度变化示意图；在使用OD操作时，该电压时序为0Và4Và3V，此时液晶分子亮度变化快。
图3是现有技术中OD操作的查询表中灰阶对照示意图；当OD 操作时，电路控制会依液晶面板像素的讯号变化寻找适合的后一灰阶来达到较快的变化速度，以0阶转换到128阶为例，查表结果是150阶对应128阶。
OD技术在业界使用已久，但使用在高更新率的液晶面板上时，由于1Frame（帧）的时间会变短，虽然OD操作可给液晶分子一段时间的过驱动电压，但由于液晶分子的转动速度跟不上，在设定时间长度内不足以让液晶分子转动至期望亮度的90%，影响了OD操作的效果。上述高更新率是相对于现有的液晶技术而定义的，在现有的通常为60Hz的更新率下，液晶分子在设定的时间内，其反应速度一般能够满足OD操作的要求，使显示画面达到理想的亮度。不过，随着更新率的提高，帧转换的时间会变短，导致在某一更新率以上执行OD操作时，虽然液晶分子在过驱动电压的作用下其反应速度已经有所提升，但是在有限的时间内上述反应速度仍然不够快，实现不了OD操作预定的目标，显示画面达不到理想的亮度。
以更新率240Hz为例，在正常的OD操作下，其1frame的时间大致为4.15ms（1/240秒），更新率为60Hz时，1frame的时间大致为16.6ms。就现有的液晶技术而言，液晶分子执行大部分灰阶转换所需的时间都在5ms以上。因此，在240Hz下进行OD操作时，液晶分子还没到准位时，已停止给OD，恢复成正常的驱动电压，液晶分子转动变慢，导致转动不到位，OD操作达到不到预想的效果。
以0阶转换到128阶为例，电压时序为0Và4Và3V。图4是更新率为60Hz时OD操作的液晶分子亮度随时间变化示意图；此时，液晶分子可以在一个frame时间（16.6ms）内转动到位，达到期望亮度的90%。从图中可以看出，在没有OD操作下，要使亮度由10%达到90%时，需要Δt时间；而在OD操作下，亮度由10%达到90%只需要Δt’时间（Δt’<Δt）。
图5是更新率为240Hz时OD操作的液晶分子亮度随时间变化示意图；作为对比，在60Hz的更新率下，有OD操作和无OD操作时，液晶分子亮度随时间变化的曲线也一并描述在图5中。此时，一个frame的时间长度变成60Hz时的1/4时间（16.6msà4.15ms），在执行OD操作的4.15ms内，液晶分子未能转动到位（0à128灰阶的转动时间一般大于5ms）。
随着高更新率液晶面板的频繁使用，如何在高更新率的情形下改善OD操作，提升显示效果成为亟待解决的问题。
发明内容
本发明的主要目的为提供一种液晶显示器的驱动方法及液晶显示器，提升了显示器的显示效果。
本发明提出一种液晶显示器的驱动方法，包括步骤：
当从上一帧向下一帧转换时，根据上一帧的帧信息查询预设的第二查询表，取得上一帧的实际灰阶值；所述帧信息至少包括灰阶值；
根据所述上一帧的实际灰阶值以及下一帧的预定灰阶值查询预设的第一查询表，获取用于灰阶转换的过驱动灰阶值；
根据所述过驱动灰阶值进行过电压驱动。
优选地，所述当从上一帧向下一帧转换时，根据上一帧的帧信息查询第二查询表，取得上一帧的实际灰阶值的步骤前还包括：
建立所述第一查询表以及第二查询表。
优选地，所述第一查询表为在过电压驱动操作中帧与帧之间灰阶转换的过驱动灰阶值查询表；所述第二查询表为在高更新率的液晶显示器中进行过电压驱动操作时，对液晶分子灰阶进行修正的对照表。
优选地，所述第二查询表的数据通过预先测试获取。
优选地，所述根据所述过驱动灰阶值进行过电压驱动的步骤之前还包括：
将所述实际灰阶值与下一帧的预设灰阶值比较取得两者差值；
判断所述差值的绝对值是否小于等于预设值；
当小于等于所述预设值时，停止进行过电压驱动。
优选地，所述预设值为5阶。
本发明还提出一种液晶显示器，包括预设的第一查询表以及预设的第二查询表；还包括：
灰阶获取单元，用于当从上一帧向下一帧转换时，根据上一帧的帧信息查询第二查询表，取得上一帧的实际灰阶值；所述帧信息至少包括灰阶值；
过驱动灰阶值获取单元，用于根据所述上一帧的实际灰阶值以及下一帧的预定灰阶值查询第一查询表，获取用于灰阶转换的过驱动灰阶值；
过电压驱动单元，用于根据所述过驱动灰阶值进行过电压驱动。
优选地，还包括：
建立单元，用于建立所述第一查询表以及第二查询表。
优选地，所述第一查询表为在过电压驱动操作中帧与帧之间灰阶转换的过驱动灰阶值查询表；所述第二查询表为在高更新率的液晶显示器中进行过电压驱动操作时，对液晶分子灰阶进行修正的对照表。
优选地，所述第二查询表的数据通过预先测试获取。
优选地，还包括比较单元，用于：
将所述实际灰阶值与下一帧的预设灰阶值比较取得两者差值；
判断所述差值的绝对值是否小于等于预设值；
当小于等于预设值时，停止进行过电压驱动。
优选地，所述预设值为5阶。
本发明还提出一种液晶显示器，包括：
建立单元，用于建立所述第一查询表以及第二查询表；所述第一查询表为在过电压驱动操作中帧与帧之间灰阶转换的过驱动灰阶值查询表；所述第二查询表为在高更新率的液晶显示器中进行过电压驱动操作时，对液晶分子灰阶进行修正的对照表；
灰阶获取单元，用于当从上一帧向下一帧转换时，根据上一帧的帧信息查询第二查询表，取得上一帧的实际灰阶值；所述帧信息至少包括灰阶值；
过驱动灰阶值获取单元，用于根据所述上一帧的实际灰阶值以及下一帧的预定灰阶值查询第一查询表，获取用于灰阶转换的过驱动灰阶值；
过电压驱动单元，用于根据所述过驱动灰阶值进行过电压驱动。
优选地，所述第二查询表的数据通过预先测试获取。
优选地，所述液晶显示器还包括比较单元，用于：
将所述实际灰阶值与下一帧的预设灰阶值比较取得两者差值；
判断所述差值的绝对值是否小于等于预设值；
当小于等于预设值时，停止进行过电压驱动。
优选地，所述预设值为5阶。
本发明的液晶显示器的驱动方法及液晶显示器，通过增加设置第二查询表进行灰阶修正，并将修正后的实际灰阶值与下一帧的预设灰阶值进行比较，根据两者差值的绝对值选择执行常规的电压驱动或者过电压驱动操作，避免由于使用不恰当操作而影响显示器的显示效果，从而可提升了液晶显示器的显示效果。
附图说明
图1 是现有技术中没有OD操作时的液晶分子亮度变化示意图；
图2 是现有技术中使用OD操作时的液晶分子亮度变化示意图；
图3 是现有技术中OD操作的查询表中灰阶对照示意图；
图4 是现有技术中60Hz时OD操作的液晶分子亮度随时间变化示意图；
图5 是现有技术中240Hz时OD操作的液晶分子亮度随时间变化示意图；
图6 是本发明一种液晶显示器的驱动方法的第一实施例的步骤流程示意图；
图7 是本发明一种液晶显示器的驱动方法的第二实施例的步骤流程示意图；
图8 是图6、图7所述液晶显示器的驱动方法的帧转换操作示意图；
图9 是图6、图7所述液晶显示器的驱动方法预设第一查询表的查询示意图；
图10 是图6、图7所述液晶显示器的驱动方法预设第二查询表的查询示意图；
图11 是本发明一种液晶显示器的驱动方法的第三实施例的步骤流程示意图；
图12 是本发明一种液晶显示器的驱动方法给定错误过电压的亮度显示示意图；
图13 是本发明一种液晶显示器的第一实施例的结构示意图；
图14 是本发明一种液晶显示器的第二实施例的结构示意图；
图15 是本发明一种液晶显示器的第三实施例的结构示意图。
本发明目的的实现、功能特点及优点将结合实施例，参照附图做进一步说明。
具体实施方式
应当理解，此处所描述的具体实施例仅仅用以解释本发明，并不用于限定本发明。
液晶显示器在高更新率的情况下，想改变现有OD技术中效果不佳，可从两个方面考虑：
一方面加大OD操作中的电压，提升液晶分子的反应速度（转得更快），在较短时间内即可达到期望亮度的90%；但电压的使用是有限制的，如果给过大的电压，可能起到反效果，使液晶分子的转动效果更差；
另一方面则是增加OD操作的时间，即给过驱动电压的时间加长；但OD操作中查询表的查询方式是以前一个frame的讯号与后一个frame比较，查表后得到相应的过驱动灰阶值。比如以0à128à128阶为例，其查询结果为0à150(+22)à128(+0) ，+0即为不作OD操作，当讯号在第三个frame时应该是128阶，但实际情况是由于液晶分子的反应时间不够，达不到128阶；修正上述二者之间不一致即为本发明技术重点。
图6是本发明一种液晶显示器的驱动方法的第一实施例的步骤流程示意图。参照图6，提出本发明一种液晶显示器的驱动方法的一实施例，其中该方法包括：
步骤S10、当从上一帧向下一帧转换时，根据上一帧的帧信息查询预设的第二查询表，取得上一帧的实际灰阶值；该帧信息至少包括灰阶值；
步骤S11、根据所述上一帧的实际灰阶值以及下一帧的预定灰阶值查询预设的第一查询表，获取用于灰阶转换的过驱动灰阶值；
步骤S12、根据所述过驱动灰阶值进行过电压驱动。
本实施例的液晶显示器的驱动方法，通过增加设置第二查询表进行灰阶修正，提升了液晶显示器的显示效果。
图7是本发明一种液晶显示器的驱动方法的第二实施例的步骤流程示意图，该第二实施例是建立在图6所示第一实施例基础上的另一步骤流程示意图。参照图7，基于第一实施例，上述步骤S10前还包括：
步骤S9、建立所述第一查询表以及第二查询表。
上述第一查询表可为在OD（过电压驱动）操作中帧与帧之间灰阶转换的过驱动灰阶值查询表，该第一查询表可以采用现有技术的过驱动查询表。在OD操作中，液晶显示器可通过前后两帧的灰阶值，查询该第一查询表查得相应的过驱动灰阶值。上述第二查询表可为在高更新率的液晶显示器中进行OD操作时，对液晶分子实际状态（灰阶）进行修正的对照表。上述第一查询表以及第二查询表，可通过预先的实验获取相应数据而建立，不同类型的液晶显示器、液晶显示面板因具体参数（比如更新率）不相同，通常会有不同的第一查询表和第二查询表。该高更新率可为高于60Hz的更新率。
图8是图6、图7所述液晶显示器的驱动方法的帧转换操作示意图。参照图8，当从第一帧（第N-1帧）向第二帧（第N帧）转换时，接收第N帧并从存储器（Memory）中提取第N-1帧进行比较后，首先查询第一查询表获取过驱动灰阶值进行第一次OD操作；在进行所述第一次OD操作后，根据第N帧在第一次OD操作时的目标灰阶值查询第二查询表，取得该帧在第一次OD操作后的实际灰阶值，形成新的帧信息（影像）；在从第二帧向第三帧（第N+1帧）转换时，根据所述第N帧的实际灰阶值和第N+1帧的目标灰阶值查询第一查询表获取所需的过驱动灰阶值，进行第二次OD操作。然后依此类推。
参照图9以及图10，图9和图10分别为图6、图7所述液晶显示器的驱动方法的预设第一查询表以及预设第二查询表的查询示意图。
灰阶（帧）的转换以0à128à128à128为例，当更新率为60Hz时，进行OD操作为：0à150à128à128，对应的液晶状态为：0à128à128à128（液晶转动到位）；当更新率为240Hz时，进行OD操作为：0à150à128à128，但在未进行修正的情况下，液晶的实际状态为：0à100à115à128，OD操作的效果不理想，显示画面达不到预定的亮度。本发明的液晶显示器的驱动方法通过第二查询表修正OD操作后液晶状态对应的灰阶值，取得合适的过驱动灰阶值，对下一次OD操作进行修正，使液晶趋于理想状态。
上述更新率为240Hz时从0阶转换到128阶，查询第一查询表可知OD操作需要150阶的过驱动灰阶值（大于128阶），但由于一帧的OD操作时间较短（4.15ms），所以在下一帧时液晶并没有到达预设亮度的128阶，假定实际只有100阶（具体数值可以通过实验测定），但是系统仍默认液晶状态已经达到128阶。而下一帧为128阶，现有技术在进行OD操作时先查询第一查询表，由于是128阶转换到128阶，系统将得到128阶的过驱动灰阶值，不作OD操作。而在本发明中，在OD操作之后、进行下一帧转换前，需要通过查询第二查询表并根据前一OD操作的实际情况对执行该OD操作后液晶状态的实际情况进行修正，例如通过查询第二查询表可得到前一OD操作后液晶的实际状态仅达到100阶，离128阶的OD操作目标值还有较大的距离，因此本发明的液晶显示器的驱动方法将该预设亮度的128阶修正至实际的100阶，再查询第一查询表，查询到100阶转换到128阶的对应的过驱动灰阶值为130阶，获取该过驱动灰阶值进行下一帧的OD操作，该下一帧OD操作后得到的实际液晶状态由第二查询表可知为115阶，还需继续查询第一查询表获取115à128的过驱动灰阶值进行下一步OD操作，如此可利用第二查询表修正高更新率液晶面板执行OD操作产生的偏差，提升OD操作的效果。
图11是本发明一种液晶显示器的驱动方法的第三实施例的步骤流程示意图，该第三实施例是建立在图7所示第二实施例基础上的又一步骤流程示意图。参照图11，相较于第二实施例，在上述步骤S12之前还包括：
步骤S13、将所述实际灰阶值与下一帧的预设灰阶值比较取得两者差值；
步骤S14、判断所述差值的绝对值是否小于等于预设值；如是，则进行步骤S15；否则，进行步骤S11；
步骤S15、停止进行过电压驱动。
在灰阶转换中，若转换的两灰阶值相差太近，此时若作OD操作，可能让灰阶的阶调产生突然过亮的不连续，因此在查询第二查询表进行灰阶值修正后，即可将修正后的实际灰阶值与下一帧的预设灰阶值进行比较，如果两者的差值的绝对值小于等于预设值（比如小于等于5阶），则执行常规的驱动即可，无需进行过电压驱动，避免影响显示器的显示效果。
通过上述第二查询表进行灰阶修正，除了可以改善驱动效果外，还具有去除讯号错误的功能。以160à0à160à0为例，在240Hz的更新率下，由第一查询表可知从160à0会以0阶的过驱动灰阶值来驱动，但因反应时间不够，液晶状态未到位，假设只到40阶（160à40）；若未经过第二查询表修正，按照现有的OD操作，系统默认液晶已经达到了0阶，接下来会在第一查询表中查到从0à160将给定200阶的过驱动灰阶值进行驱动；由于实际状态为40à160，过驱动灰阶值只需设置为180阶，给定200阶的过驱动灰阶值将使得讯号强度会过强，显示的运动目标边缘容易产生亮、暗双边。若经过第二查询表进行修正，则通过该第二查询表即可获得下一帧的变化不应该是0à160，而是40à160；再通过第一查询表，就可查到合理的过驱动灰阶值是180阶，从而可纠正讯号错误，执行合理的OD操作。图12是对应上述例子的一种液晶显示器的驱动方法给定错误过驱动灰阶值的亮度显示示意图。参照图12，液晶分子进行160à0à160的灰阶切换，由于在0à160时，给定的过驱动灰阶值过量，OD操作后液晶分子的实际状态已经超过了160阶，导致影像亮度变得比预期亮，反映在显示图像上，例如原本一条160阶的线在黑色背景移动，会变成一条比160阶更亮的线。
图13是本发明一种液晶显示器的第一实施例的结构示意图。参照图13，提出本发明一种液晶显示器的一实施例，其中该液晶显示器包括预设的第一查询表以及预设的第二查询表；还包括灰阶获取单元、过驱动灰阶值获取单元以及过电压驱动单元；该灰阶获取单元，用于当从上一帧向下一帧转换时，根据上一帧的帧信息查询第二查询表，取得上一帧的实际灰阶值；该帧信息至少包括灰阶值；该过驱动灰阶值获取单元，用于根据所述上一帧的实际灰阶值以及下一帧的预定灰阶值查询第一查询表，获取灰阶转换所需的过驱动灰阶值；该过电压驱动单元，用于根据所述过驱动灰阶值进行过电压驱动。
本实施例的液晶显示器，通过增加设置第二查询表进行灰阶修正，提升了液晶显示器的显示效果。
图14是本发明一种液晶显示器的第二实施例的结构示意图，其是建立在图13所示液晶显示器的第一实施例基础上的另一结构示意图。参照图14，基于上一实施例，本实施例的液晶显示器还可包括：建立单元，用于建立所述第一查询表以及第二查询表。
上述第一查询表可为在OD（过电压驱动）操作中帧与帧之间灰阶转换的过驱动灰阶值（OD值）查询表，该第一查询表可以采用现有技术的过驱动查询表。在OD操作中，液晶显示器利用过驱动灰阶值获取单元通过前后两帧的灰阶值，查询该第一查询表查得执行OD操作所需的过驱动灰阶值。上述第二查询表可为在高更新率的液晶显示器中进行OD操作时，对液晶分子实际状态（灰阶）进行修正的对照表，上述液晶显示器可利用灰阶获取单元从该第二查询表中获取修正的灰阶值。上述第一查询表以及第二查询表，可通过预先的实验获取相应数据利用上述建立单元建立，不同的液晶显示面板和不同的高更新率可以设置各自的第一查询表和第二查询表。
参照图8，在本实施例的液晶显示器中，当从第一帧（第N-1帧）向第二帧（第N帧）转换时，接收第N帧并从存储器（Memory）中提取第N-1帧进行比较后，首先查询第一查询表获取相应的过驱动灰阶值进行第一次OD操作；在进行所述第一次OD操作后，根据第N帧在第一次OD操作时的目标灰阶值查询第二查询表取得实际灰阶值，形成新的帧信息（影像）；在从第二帧向第三帧（第N+1帧）转换时，根据所述第N帧的实际灰阶值和第N+1帧的目标灰阶值查询第一查询表获取相应的过驱动灰阶值，进行第二次OD操作。然后依此类推。
参照图9以及图10，灰阶（帧）的转换以0à128à128à128为例，当更新率为60Hz时，进行OD操作为：0à150à128à128，对应的液晶状态为：0à128à128à128（液晶转动到位）；当更新率为240Hz时，进行OD操作为：0à150à128à128，但在未进行修正的情况下，液晶的实际状态为：0à100à115à128，OD操作的效果不理想，显示画面达不到预定的亮度。本发明的液晶显示器通过第二查询表修正OD操作后液晶状态对应的灰阶值，获取合适的过驱动灰阶值，对下一次OD操作进行修正，使液晶状态趋于理想状态。
上述更新率为240Hz时从0阶转换到128阶，查询预设的第一查询表可知OD操作需要150阶的过驱动灰阶值（大于128阶），但由于一帧的OD操作时间较短（4.15ms），所以在下一帧时液晶并没有到达预设亮度的128阶，假定实际只有100阶（具体数值可以通过实验测定），但是系统仍默认液晶状态已经达到128阶。而下一帧为128阶，现有技术在进行OD操作时先查询预设的第一查询表，由于是128阶转换到128阶，系统将得到128阶的过驱动灰阶值，不作OD操作。而在本发明中，在OD操作之后、进行下一帧转换前，需要通过查询预设的第二查询表并根据前一OD操作的实际情况对该OD操作后液晶状态的实际情况进行修正，例如通过查询预设的第二查询表可得到前一OD操作后液晶的实际状态仅达到100阶，离128阶的OD操作目标值还有较大的距离，因此本发明的液晶显示器需要将该预设亮度的128阶修正至实际的100阶，再查询预设的第一查询表，查询到100阶转换到128阶的对应的过驱动灰阶值为130阶，获取该过驱动灰阶值进行下一帧的OD操作，该下一帧OD操作后得到的实际液晶状态由第二查询表可知为115阶，还需继续查询预设的第一查询表获取115à128的过驱动灰阶值进行下一步OD操作，如此可利用预设的第二查询表修正高更新率液晶面板执行OD操作产生的偏差，提升OD操作的效果。
图15是本发明一种液晶显示器的第三实施例的结构示意图，其是建立在图14所示液晶显示器的第二实施例基础上的又一结构示意图。参照图15，本实施例的液晶显示器，还包括比较单元，用于：将所述实际灰阶值与下一帧的预设灰阶值比较取得两者差值；判断所述差值的绝对值是否小于等于预设值；当小于等于预设值时，停止进行过电压驱动。
在灰阶转换中，若转换的两灰阶值相差太近，此时若作OD操作，可能让灰阶的阶调产生突然过亮的不连续，因此在查询第二查询表进行灰阶值修正后，液晶显示器即可利用该比较单元将修正后的实际灰阶值与下一帧的预设灰阶值进行比较，如果两者差值的绝对值小于等于预设值（比如小于等于5阶），只需执行常规的电压驱动即可，无需进行过电压驱动操作，避免影响显示器的显示效果。
通过上述预设的第二查询表进行灰阶修正，除了可以改善驱动效果外，还具有去除讯号错误的功能。以160à0à160à0为例，在240Hz的更新率下，由第一查询表可知，从160à0会以0阶的过驱动灰阶值来驱动，但因过驱动时间不够，液晶状态未到位，假设只到40阶（160à40）；若未经过预设的第二查询表修正，按照现有的OD操作，系统默认液晶已经达到了0阶，接下来会在预设的第一查询表中查到从0à160将给定200阶的过驱动灰阶值进行驱动；由于实际状态为40à160，过驱动灰阶值只需设置为180阶，给定200阶的过驱动灰阶值将使得讯号强度会过强，显示的运动目标边缘容易产生亮、暗双边。若经过预设的第二查询表进行修正，则通过该预设的第二查询表即可获得下一帧的变化不应该是0à160，而是40à160；再通过预设的第一查询表，就可查到合理的过驱动灰阶值是180阶，从而可纠正讯号错误，执行合理的OD操作。图12是对应上述例子的一种液晶显示器的驱动方法给定错误过过驱动灰阶值的亮度显示示意图。参照图12，液晶分子进行160à0à160的灰阶切换，由于在0à160时，给定的过驱动灰阶值过量，OD操作后液晶分子的实际状态已经超过了160阶，导致影像亮度变得比预期亮，反映在显示图像上，例如原本一条160阶的线在黑色背景移动，会变成一条比160阶更亮的线。
以上所述仅为本发明的优选实施例，并非因此限制本发明的专利范围，凡是利用本发明说明书及附图内容所作的等效结构或等效流程变换，或直接或间接运用在其他相关的技术领域，均同理包括在本发明的专利保护范围内。

Claims (16)

  1. 一种液晶显示器的驱动方法，其特征在于，包括步骤：
    当从上一帧向下一帧转换时，根据上一帧的帧信息查询预设的第二查询表，取得上一帧的实际灰阶值；所述帧信息至少包括灰阶值；
    根据所述上一帧的实际灰阶值以及下一帧的预定灰阶值查询预设的第一查询表，获取用于灰阶转换的过驱动灰阶值；
    根据所述过驱动灰阶值进行过电压驱动。
  2. 根据权利要求1所述的液晶显示器的驱动方法，其特征在于，所述当从上一帧向下一帧转换时，根据上一帧的帧信息查询第二查询表，取得上一帧的实际灰阶值的步骤前还包括：
    建立所述第一查询表以及第二查询表。
  3. 根据权利要求1所述的液晶显示器的驱动方法，其特征在于，所述第一查询表为在过电压驱动操作中帧与帧之间灰阶转换的过驱动灰阶值查询表；所述第二查询表为在高更新率的液晶显示器中进行过电压驱动操作时，对液晶分子灰阶进行修正的对照表。
  4. 根据权利要求1所述的液晶显示器的驱动方法，其特征在于，所述第二查询表的数据通过预先测试获取。
  5. 根据权利要求1至4中任一项所述的液晶显示器的驱动方法，其特征在于，所述根据所述过驱动灰阶值进行过电压驱动的步骤之前还包括：
    将所述实际灰阶值与下一帧的预设灰阶值比较取得两者差值；
    判断所述差值的绝对值是否小于等于预设值；
    当小于等于所述预设值时，停止进行过电压驱动。
  6. 根据权利要求5所述的液晶显示器的驱动方法，其特征在于，所述预设值为5阶。
  7. 一种液晶显示器，其特征在于，包括预设的第一查询表以及预设的第二查询表；还包括：
    灰阶获取单元，用于当从上一帧向下一帧转换时，根据上一帧的帧信息查询第二查询表，取得上一帧的实际灰阶值；所述帧信息至少包括灰阶值；
    过驱动灰阶值获取单元，用于根据所述上一帧的实际灰阶值以及下一帧的预定灰阶值查询第一查询表，获取用于灰阶转换的过驱动灰阶值；
    过电压驱动单元，用于根据所述过驱动灰阶值进行过电压驱动。
  8. 根据权利要求7所述的液晶显示器，其特征在于，还包括：
    建立单元，用于建立所述第一查询表以及第二查询表。
  9. 根据权利要求7所述的液晶显示器，其特征在于，所述第一查询表为在过电压驱动操作中帧与帧之间灰阶转换的过驱动灰阶值查询表；所述第二查询表为在高更新率的液晶显示器中进行过电压驱动操作时，对液晶分子灰阶进行修正的对照表。
  10. 根据权利要求7所述的液晶显示器，其特征在于，所述第二查询表的数据通过预先测试获取。
  11. 根据权利要求7至10中任一项所述的液晶显示器，其特征在于，还包括比较单元，用于：
    将所述实际灰阶值与下一帧的预设灰阶值比较取得两者差值；
    判断所述差值的绝对值是否小于等于预设值；
    当小于等于预设值时，停止进行过电压驱动。
  12. 根据权利要求11所述的液晶显示器，其特征在于，所述预设值为5阶。
  13. 一种液晶显示器，其特征在于，包括：
    建立单元，用于建立所述第一查询表以及第二查询表；所述第一查询表为在过电压驱动操作中帧与帧之间灰阶转换的过驱动灰阶值查询表；所述第二查询表为在高更新率的液晶显示器中进行过电压驱动操作时，对液晶分子灰阶进行修正的对照表；
    灰阶获取单元，用于当从上一帧向下一帧转换时，根据上一帧的帧信息查询第二查询表，取得上一帧的实际灰阶值；所述帧信息至少包括灰阶值；
    过驱动灰阶值获取单元，用于根据所述上一帧的实际灰阶值以及下一帧的预定灰阶值查询第一查询表，获取用于灰阶转换的过驱动灰阶值；
    过电压驱动单元，用于根据所述过驱动灰阶值进行过电压驱动。
  14. 根据权利要求13所述的液晶显示器，其特征在于，所述第二查询表的数据通过预先测试获取。
  15. 根据权利要求13或14中任一项所述的液晶显示器，其特征在于，还包括比较单元，用于：
    将所述实际灰阶值与下一帧的预设灰阶值比较取得两者差值；
    判断所述差值的绝对值是否小于等于预设值；
    当小于等于预设值时，停止进行过电压驱动。
  16. 根据权利要求15所述的液晶显示器，其特征在于，所述预设值为5阶。
PCT/CN2011/081012 2011-08-19 2011-10-20 液晶显示器的驱动方法及液晶显示器 WO2013026227A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US13/375,232 US20130044144A1 (en) 2011-08-19 2011-10-20 Liquid crystal display and driving method thereof

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN 201110240016 CN102290036B (zh) 2011-08-19 2011-08-19 液晶显示器的驱动方法及液晶显示器
CN201110240016.6 2011-08-19

Publications (1)

Publication Number Publication Date
WO2013026227A1 true WO2013026227A1 (zh) 2013-02-28

Family

ID=45336402

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2011/081012 WO2013026227A1 (zh) 2011-08-19 2011-10-20 液晶显示器的驱动方法及液晶显示器

Country Status (2)

Country Link
CN (1) CN102290036B (zh)
WO (1) WO2013026227A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110970000A (zh) * 2019-12-25 2020-04-07 Tcl华星光电技术有限公司 驱动方法、驱动装置及液晶显示装置
CN114566131A (zh) * 2021-12-30 2022-05-31 京东方科技集团股份有限公司 显示亮度控制方法和装置、显示查询表获取方法和装置

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103151015A (zh) * 2013-03-12 2013-06-12 京东方科技集团股份有限公司 过驱动方法、电路、显示面板和显示装置
CN103474042B (zh) * 2013-09-12 2015-12-23 青岛海信电器股份有限公司 一种过压驱动的方法、装置及显示设备
CN105225648B (zh) * 2015-10-16 2017-09-15 武汉华星光电技术有限公司 一种降低影像残留的方法及液晶显示器
CN105161047B (zh) * 2015-10-26 2017-08-25 京东方科技集团股份有限公司 一种显示面板的显示驱动方法、显示驱动电路及显示装置
TWI616858B (zh) * 2017-04-06 2018-03-01 友達光電股份有限公司 過驅動方法、時序控制器及顯示器
CN107516497A (zh) * 2017-09-19 2017-12-26 惠科股份有限公司 液晶显示器及其驱动方法
CN110085177A (zh) * 2018-01-25 2019-08-02 奇景光电股份有限公司 显示设备与过驱动方法
CN109377949A (zh) * 2018-10-22 2019-02-22 深圳市华星光电半导体显示技术有限公司 Tft-lcd面板二次过压补偿方法及装置
CN109410850B (zh) * 2018-12-24 2021-02-12 惠科股份有限公司 一种过驱动亮度值查找表的调试方法、使用方法和显示面板
CN109671412B (zh) * 2019-02-18 2021-05-25 京东方科技集团股份有限公司 过驱动方法、装置、液晶显示面板的控制器和显示设备
CN110379391B (zh) * 2019-07-02 2021-08-06 南京中电熊猫液晶显示科技有限公司 一种液晶显示面板以及改善液晶显示面板动态画面拖尾的方法
CN110428787B (zh) * 2019-07-23 2021-08-03 Tcl华星光电技术有限公司 过驱动查找表的建立系统和建立方法
CN111933087A (zh) * 2020-08-19 2020-11-13 惠科股份有限公司 液晶显示装置及其驱动方法
CN114627827B (zh) * 2020-12-08 2023-10-24 京东方科技集团股份有限公司 灰阶补偿方法、灰阶补偿模组和液晶显示装置
CN116758849A (zh) * 2023-05-25 2023-09-15 重庆惠科金渝光电科技有限公司 显示面板的驱动方法及显示装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101253544A (zh) * 2005-08-31 2008-08-27 夏普株式会社 Lcd和液晶显示装置以及它们的驱动方法
JP2009116123A (ja) * 2007-11-07 2009-05-28 Sharp Corp 駆動回路および駆動回路を備えた液晶表示装置
CN101764924A (zh) * 2008-12-23 2010-06-30 乐金显示有限公司 用于处理液晶显示设备的视频数据的方法和装置

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5173342B2 (ja) * 2007-09-28 2013-04-03 株式会社ジャパンディスプレイイースト 表示装置
JP4779167B2 (ja) * 2008-03-19 2011-09-28 奇美電子股▲ふん▼有限公司 液晶表示装置の駆動方法、オーバードライブ補正装置、オーバードライブ補正装置のデータ作成方法、液晶表示装置及び電子装置
KR101490894B1 (ko) * 2008-10-02 2015-02-09 삼성전자주식회사 계조 데이터를 보정하기 위한 디스플레이 장치, 타이밍 컨트롤러 및 이를 이용한 패널 구동방법

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101253544A (zh) * 2005-08-31 2008-08-27 夏普株式会社 Lcd和液晶显示装置以及它们的驱动方法
JP2009116123A (ja) * 2007-11-07 2009-05-28 Sharp Corp 駆動回路および駆動回路を備えた液晶表示装置
CN101764924A (zh) * 2008-12-23 2010-06-30 乐金显示有限公司 用于处理液晶显示设备的视频数据的方法和装置

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110970000A (zh) * 2019-12-25 2020-04-07 Tcl华星光电技术有限公司 驱动方法、驱动装置及液晶显示装置
CN114566131A (zh) * 2021-12-30 2022-05-31 京东方科技集团股份有限公司 显示亮度控制方法和装置、显示查询表获取方法和装置
CN114566131B (zh) * 2021-12-30 2023-12-22 京东方科技集团股份有限公司 显示亮度控制方法和装置、显示查询表获取方法和装置

Also Published As

Publication number Publication date
CN102290036A (zh) 2011-12-21
CN102290036B (zh) 2013-01-23

Similar Documents

Publication Publication Date Title
WO2013026227A1 (zh) 液晶显示器的驱动方法及液晶显示器
WO2017000358A1 (zh) 液晶显示面板的Gamma调整方法及装置
WO2010131843A4 (ko) 타이밍 컨트롤러, 컬럼 드라이버 및 이를 갖는 표시 장치
WO2017201811A1 (zh) 一种液晶显示器的驱动方法及驱动装置
WO2020134964A1 (zh) 显示面板及其控制方法、控制设备
WO2016095239A1 (zh) 一种图像显示方法、图像显示装置及显示器件
JP2003108103A (ja) 液晶表示装置の駆動方法及び装置
WO2018068433A1 (zh) 一种液晶显示器及其补偿数据存储方法
WO2018170984A1 (zh) 一种显示面板的驱动方法、时序控制器及液晶显示器
WO2013033928A1 (zh) Lcd过激驱动方法、装置及液晶显示器
WO2018128308A1 (ko) 디스플레이 패널의 무라 보정방법
WO2017164458A1 (en) Organic light emitting diode display device and method of operating the same
WO2020135075A1 (zh) 显示器及其显示面板的驱动装置、方法
WO2020096202A1 (en) Display apparatus and control method thereof
WO2016173006A1 (zh) 一种液晶面板及其驱动方法
WO2019240412A1 (ko) 표시 패널의 구동 방법 및 이를 수행하기 위한 표시 장치
WO2020062556A1 (zh) 伽马电压调节电路及显示装置
WO2017131409A2 (en) Display apparatus and driving method thereof
US7839413B2 (en) Dithering method for an LCD
WO2013127092A1 (zh) 一种斜视角图像的模拟方法及装置
WO2018113167A1 (zh) 液晶显示器的驱动方法、装置及液晶显示器
US7057593B2 (en) Liquid crystal display
WO2020155257A1 (zh) 显示面板的驱动方法、装置及设备
WO2020135074A1 (zh) 显示面板及其控制方法、控制装置、控制设备
US11361720B2 (en) Display device comprising grayscale voltage output unit that outputs corrected grayscale voltage to one signal line including disconnection location

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 13375232

Country of ref document: US

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11871360

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11871360

Country of ref document: EP

Kind code of ref document: A1